59 results on '"RCP"'
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2. Structural, magnetic, magnetocaloric, investigations on La0.8−xKxSr0.2Mn0.95Ni0.05O3 (x = 0.05, 0.10 and 0.15) at room temperature
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Xie, Zhuojia, Zhang, Weijian, Zou, Zhengguang, and Jiang, Xinyu
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- 2022
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3. Projections of temperature-associated mortality risks under the changing climate in an ageing society.
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Sharma, A., Lin, Y.-K., Chen, C.-C., Deng, L., and Wang, Y.-C.
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PSYCHOLOGICAL aspects of aging , *RESPIRATORY diseases , *TEMPERATURE , *RETROSPECTIVE studies , *RISK assessment , *FORECASTING , *DEFENSE mechanisms (Psychology) , *CLIMATE change ,MORTALITY risk factors - Abstract
This study aimed to project future temperature-associated mortality risk and additional deaths among Taiwan's elderly (aged >65 years) population. This study investigated retrospective temperature-mortality risk associations and future mortality projections. A distributed lag non-linear model and random effect meta-analyses were employed to assess the risk of daily temperature-associated deaths in all-cause, circulatory, and respiratory diseases. Using the statistical downscaling temperature projections of the Representative Concentration Pathways (RCPs; i.e. RCP2.6, RCP6.0 and RCP8.5), future risk of mortalities were projected among the elderly for 2030–2039, 2060–2069 and 2090–2099, with a 30%, 40% and 50% expected increase in elderly population proportions, respectively. The baseline analysis from 2005 to 2018 identified that Taiwan's population is more vulnerable to cold effects than heat, with the highest cold-related mortality risk being attributed to circulatory diseases, followed by all-cause and respiratory diseases. However, future projections suggest a declining trend in cold-related mortalities and a significant rise in heat-related mortalities under different RCP scenarios. Heat-attributable mortalities under the RCP8.5 scenario by 2090–2099 would account for almost 170,360, 36,557 and 29,386 additional annual deaths among the elderly due to all-cause, circulatory and respiratory diseases, respectively. Heat-attributable all-cause mortalities among the elderly would increase by 3%, 11% and 30% under RCP2.6, RCP6.0 and RCP8.5, respectively, by 2090–2099. The findings of this study provide predictions on future temperature-related mortality among the elderly in a developed, ageing society with a hot and humid climate. The results from this study can guide public health interventions and policies for climate change and ageing society–associated health risks. [Display omitted] [ABSTRACT FROM AUTHOR]
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- 2023
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4. Importance de la réunion de concertation pluridisciplinaire (RCP) dans la prise en charge du transsexualisme.
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Leclère, F.M., Casoli, V., Flamen d'Assigny, M., Sautron, S., Diaconu, A., and Duteille, F.
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- 2023
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5. Anticipating the potential distribution of Fasciola spp. in Gilan province of Iran: Insights from MaxEnt and climate change scenarios.
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Modabbernia, Galia, Meshgi, Behnam, and Hanafi-Bojd, Ahmad Ali
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NORMALIZED difference vegetation index , *SEASONAL temperature variations , *FASCIOLA , *FASCIOLIASIS , *PARASITIC diseases - Abstract
Fasciolosis, a parasitic disease affecting humans and animals, is uniquely influenced by climatic and environmental factors. Gilan province in northern Iran is recognized as a high-endemic area for this parasite. This study aims to assess the prevalence of fasciolosis in Gilan province during the current period and forecast the distribution pattern of the parasite in future periods by analyzing climatic variables and identifying the most critical factors impacting Fasciola. To evaluate the present status of fasciolosis in Gilan, we collected 189 sheep fecal samples from different parts of the province and quantified eggs per gram of feces in each sample. Meteorological and environmental data were obtained and clipped to the study area. A total of 19 presence points were used to model the habitat suitability of Fasciola spp. through the maximum entropy (MaxEnt) algorithm, with jackknife analysis to determine variable importance. To project the potential distribution of Fasciola spp. in Gilan province under future scenarios, we employed MaxEnt using current (1970–2000) and projected climatic data based on three representative concentration pathway scenarios (RCP 2.6, RCP 4.5, and RCP 8.5) to predict habitat suitability in 2030, 2050, and 2070. The results of this study indicate the proportion of Fasciola spp. infection was highest in Talesh (46.37 %) and Langarud (45.7 %), while Rudsar (0 %) and Shaft (16.25 %) exhibited the lowest infection rates in Gilan province. MaxEnt modeling highlighted the significance of bioclimatic variables, particularly those associated with vegetation and temperature, such as temperature seasonality (Bio4) and normalized difference vegetation index (NDVI). The ecological niche modeling illustrated that the highest potential distribution for Fasciola in Gilan province is concentrated in the north-western and central regions, exhibiting an 80–100 % potential. However, projections for the future indicate a decrease to less than 20 % suitability for most of the province under all three scenarios until 2070. This study provides valuable insights into the dynamic relationship between climatic variables and Fasciola distribution, enabling better preparedness and control strategies for this trematode in Gilan province and other regions with similar climates. • Gilan province in northern Iran is recognized as an endemic area for Fasciola spp. • Utilizing environmental and bioclimatic variables, MaxEnt model predicted high-risk areas for Fasciola spp. • Temperature seasonality (bio4) and NDVI are strongly linked to the distribution of Fasciola spp. • Under climate change scenarios, the presence of Fasciola spp. in Gilan province is predicted to decrease until 2070. [ABSTRACT FROM AUTHOR]
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- 2024
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6. Dynamic magnetic and magnetocaloric behaviors of a Kagome-like cluster.
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Shi, Kai-Le, Jiang, Wei, and Wu, Wei-Chen
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EXCHANGE interactions (Magnetism) , *MAGNETIC cooling , *MONTE Carlo method , *MAGNETIC properties , *MAGNETOCALORIC effects , *MAGNETIC entropy - Abstract
By utilizing the Monte Carlo simulation, how different physical parameters affect the dynamic magnetic properties and magnetocaloric effects of a Kagome-like cluster with mixed spins (3/2, 2) are explored. The findings show that changing the values of the exchange coupling | J |, | J s |, and | J 2 | had no impact on the saturation order parameters of the system. Under specific parameter conditions, the magnetization susceptibility curve displays double peaks, and compensation phenomena are noted. The impacts of h bias and h osc on the blocking temperature of the system are opposite. In addition, the effects of various parameters on the magnetization, magnetic entropy change, and relative cooling power of the ferromagnetic system under a static magnetic field are given. The strong exchange coupling is found to negatively affect the magnetic refrigeration efficiency of the material, while a strong magnetic field enhances the system's relative cooling power. • Ising model with mixed spin (3/2, 2) was proposed to describe a Kagome-like cluster. • Dynamic magnetic behaviors of the system under an oscillating magnetic field were examined by Monte Carlo simulations. • Compensation phenomenon and multiple saturation order parameters have been found. • The crucial physical quantities, such as magnetic entropy change and RCP, were examined to study magnetic refrigeration. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Risk map for the range expansion of Thrips palmi in Korea under climate change: Combining species distribution models with land-use change.
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Hong, Jinsol, Lee, Gwan-Seok, Park, Jung-Joon, Mo, Hyoung-ho, and Cho, Kijong
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Climate change and land-use change are the most powerful drivers for the invasion of alien species. To understand the integrated effects of these two drivers on pest invasion risk in the future, this study assessed how they impact the invasion risk of Thrips palmi Karny, which is the most serious invasive species in the Korean peninsula. The potential distribution of T. palmi was projected with a MaxEnt model for current and future climate change scenarios (RCP 4.5 and 8.5) based on occurrence records. The potential distribution extends to the north over time, except the eastern high mountainous area, for both RCPs in 2075. The MaxEnt outputs were filtered with agricultural area using data from three land-use change scenarios derived from the Shared Socio-economic Pathways (SSPs), because T. palmi populations can only be sustained in agricultural areas. The potential risk of T. palmi , based on the potential distribution probability in the future agricultural area, increased over time under all RCPs-SSPs combinations. The total area of T. palmi occurrence increased under RCPs-SSP1 and -SSP2 but decreased under RCPs-SSP3, due to agricultural areas being converted to urban areas. In conclusion, based on future climate change scenarios, T. palmi could be distributed throughout the Korean peninsula in the future. The invasion risk in agricultural areas will increase substantially; thus, intensive control measures for T. palmi are required in the future. Our research suggests that using both climate change and land-use change in pest risk mapping study can provide informative data for management strategy. Unlabelled Image • Invasion risk of Thrips palmi was evaluated under climate/land-use change scenarios. • The MaxEnt model described the current and future distributions of T. palmi well. • The risk areas were stable for SSP1 and SSP2, but the intensity increased greatly. • In SSP3, the risk areas decreased due to a reduction in agricultural areas. • Land-use change should be considered in pest risk maps along with climate change. [ABSTRACT FROM AUTHOR]
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- 2019
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8. Identifying climate change impacts on water resources in Xinjiang, China.
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Luo, Min, Liu, Tie, Meng, Fanhao, Duan, Yongchao, Bao, Anming, Xing, Wei, Feng, Xianwei, De Maeyer, Philippe, and Frankl, Amaury
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Water resources have an important role in maintaining ecological fuctions and sustaining social and economic development. This is especially true in arid and semi-arid areas, where climate change has a large impact on water resources, such as in Xinjiang, China. Using a combination of precipitation and temperature bias correction methods, we analyzed projected changes in different hydrological components in nine high-alpine catchments distributed in Xinjiang using the Soil and Water Assessment Tool (SWAT). The impacts of elevation, area and aspect of the catchments were analyzed. The results suggested an overall warming and wetting trend for all nine catchments in the near future, with the exception of summer precipitation decreasing in some catchments. The total runoff discharge, evapotranspiration and snow/ice melting will generally increase. Warming temperature plays a more important role in the changes of each hydrological component than increasing precipitation. However, northern Xinjiang was more sensitive to predicted precipitation changes than southern Xinjiang. These results also indicate that the overall increases in water resources are not sustainable, and the impacts of climate change are associated with the elevation, area and slope aspect of the catchments. Unlabelled Image • The elevation, area and aspect of catchments affect the extent of impacts. • The impact of warming on discharge will change from positive into negative. • The overall increases in water resources in Xinjiang, China are not sustainable. [ABSTRACT FROM AUTHOR]
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- 2019
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9. An eco-friendly building coating with high self-cleaning capacity: Synergetic effect of super-hydrophobicity and photocatalytic degradation.
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Liao, Gang, Yao, Wu, She, Anming, and Bian, Xiaolei
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PHOTODEGRADATION , *FRACTAL dimensions , *CONTACT angle , *SUPERHYDROPHOBIC surfaces , *CRITICAL point (Thermodynamics) , *MECHANICAL abrasion , *EXTERIOR walls , *PHOTOVOLTAIC power systems - Abstract
• TiO 2 was coupled with RCP through carbon chain self-assembly. • PDMS and RCPT were used to prepare building self-cleaning coating. • Hydrophilicity and photocatalytic activity were regulated by changing RCPT content. • A new definition of surface roughness was proposed based on fractal dimensions. • 'Lotus effect' and photocatalytic effect jointly improved the self-cleaning capacity. Photocatalytic super-hydrophobic coating is highly appealing due to its exceptional self-cleaning capacity. In this study, recycled concrete powder (RCP) was used to support TiO 2 , and RCP@TiO 2 composites (RCPT) were incorporated into polydimethylsiloxane (PDMS) to fabricate an exterior wall self-cleaning coating. The super-hydrophobicity and photocatalytic activity of the resulting coating were modulated by adjusting the dosage of RCPT. The surface roughness was determined through fractal analysis. The findings indicated that the incorporation of RCPT generated micro-/nano-scale structures on the coating surface, which significantly enhanced its hydrophobicity. The water contact angle (WCA) of the coating surface increased with the content of RCPT. When the mass ratio of RCPT to PDMS reached 1, the sliding angle (SA) sharply decreased, resulting in a super-hydrophobic surface with WCA greater than 150° and SA less than 10°. According to the surface roughness, critical points of wetting state transition can be accurately identified. Meanwhile, the coating with the same addition of RCPT exhibited the highest photocatalytic activity. The synergistic effect of super-hydrophobicity and photocatalytic degradation contributed to the enhanced self-cleaning capacity. Due to the lotus effect, the coating exhibited high stain resistance and water repellency. Most pollutants adhering to the coating surface can be removed by rainwater rolling off. In case of fouling by organic pollutants, photocatalytic degradation can decompose adsorbed pollutants, thus restoring the lotus effect. The coating also demonstrated exceptional stability against photo-thermal erosion, mechanical abrasion, and water impact. Our research has unveiled the correlation between surface structure and properties of coating, providing valuable insights for the development of building self-cleaning coatings. [ABSTRACT FROM AUTHOR]
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- 2023
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10. An equation to predict the maximal lactate steady state from ramp-incremental exercise test data in cycling.
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Iannetta, Danilo, Fontana, Federico Y., Maturana, Felipe Mattioni, Inglis, Erin Calaine, Pogliaghi, Silvia, Keir, Daniel A., and Murias, Juan M.
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Objectives: The maximal lactate steady state (MLSS) represents the highest exercise intensity at which an elevated blood lactate concentration ([Lac]b) is stabilized above resting values. MLSS quantifies the boundary between the heavy-to-very-heavy intensity domains but its determination is not widely performed due to the number of trials required.Design: This study aimed to: (i) develop a mathematical equation capable of predicting MLSS using variables measured during a single ramp-incremental cycling test and (ii) test the accuracy of the optimized mathematical equation.Methods: The predictive MLSS equation was determined by stepwise backward regression analysis of twelve independent variables measured in sixty individuals who had previously performed ramp-incremental exercise and in whom MLSS was known (MLSSobs). Next, twenty-nine different individuals were prospectively recruited to test the accuracy of the equation. These participants performed ramp-incremental exercise to exhaustion and two-to-three 30-min constant-power output cycling bouts with [Lac]b sampled at regular intervals for determination of MLSSobs. Predicted MLSS (MLSSpred) and MLSSobs in both phases of the study were compared by paired t-test, major-axis regression and Bland-Altman analysis.Results: The predictor variables of MLSS were: respiratory compensation point (Wkg-1), peak oxygen uptake (V˙O2peak) (mlkg-1min-1) and body mass (kg). MLSSpred was highly correlated with MLSSobs (r=0.93; p<0.01). When this equation was tested on the independent group, MLSSpred was not different from MLSSobs (234±43 vs. 234±44W; SEE 4.8W; r=0.99; p<0.01).Conclusions: These data support the validity of the predictive MLSS equation. We advocate its use as a time-efficient alternative to traditional MLSS testing in cycling. [ABSTRACT FROM AUTHOR]- Published
- 2018
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11. Implications of RCP emissions on future concentration and direct radiative forcing of secondary organic aerosol over China.
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Zhang, Yu, Liao, Hong, Ding, Xiang, Jo, Duseong, and Li, Ke
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ATMOSPHERIC aerosols , *RADIATIVE forcing , *CLIMATE change , *AIR quality - Abstract
This study applies the nested-grid version of Goddard Earth Observing System (GEOS) chemical transport model (GEOS-Chem) to examine future changes (2000–2050) in SOA concentration and associated direct radiative forcing (DRF) over China under the Representative Concentration Pathways (RCPs). The projected changes in SOA concentrations over 2010–2050 generally follow future changes in emissions of toluene and xylene. On an annual mean basis, the largest increase in SOA over eastern China is simulated to be 25.1% in 2020 under RCP2.6, 20.4% in 2020 under RCP4.5, 56.3% in 2050 under RCP6.0, and 44.6% in 2030 under RCP8.5. The role of SOA in PM 2.5 increases with each decade in 2010–2050 under RCP2.6, RCP4.5, and RCP8.5, with a maximum ratio of concentration of SOA to that of PM 2.5 of 16.3% in 2050 under RCP4.5 as averaged over eastern China (20°–45°N, 100°–125°E). Concentrations of SOA are projected to be able to exceed those of sulfate, ammonium, and black carbon (BC) in the future. The future changes in SOA levels over eastern China are simulated to lead to domain-averaged (20°–45°N, 100°–125°E) DRFs of +0.19 W m −2 , +0.12 W m −2 , − 0.28 W m −2 , and −0.17 W m −2 in 2050 relative to 2000 under RCP2.6, RCP4.5, RCP6.0, and RCP8.5, respectively. Model results indicate that future changes in SOA owing to future changes in anthropogenic precursor emissions are important for future air quality planning and climate mitigation measures. [ABSTRACT FROM AUTHOR]
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- 2018
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12. An interval parameter conditional value-at-risk two-stage stochastic programming model for sustainable regional water allocation under different representative concentration pathways scenarios.
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Fu, Qiang, Li, Linqi, Li, Mo, Li, Tianxiao, Liu, Dong, Hou, Renjie, and Zhou, Zhaoqiang
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VALUE at risk , *STOCHASTIC programming , *WATER rights , *WATER temperature , *GROUNDWATER temperature - Abstract
Highlights • Optimizing the conjunctive use of surface water and groundwater at the regional scale. • Promoting the economic benefits of water resource systems while considering the penalties and risks. • Reflecting uncertainties expressed as discrete intervals and probability distributions. • Obtaining various water planning alternatives under different climate change scenarios. Abstract The shortage of water resources and the increasing competition among water users have highlighted the importance of the water allocation problem. Water availability is crucial for water resource allocation and changes frequently, leading to the necessity to predict available water. This paper develops a framework aimed to plan regional water allocations under different representative concentration pathways (RCP) scenarios using an interval parameter conditional value-at-risk (CVaR) two-stage stochastic programming model. This framework combines prediction and optimization to reflect climate change, the uncertainty of water system and the coordination between water resources allocation and risk. The feasibility and practicality of the framework are demonstrated by its application in a real-world case study in the Lower Songhua River Basin in northeast China. Comparison between the results of the developed model and actual conditions show that 11.61 × 108 m3 volume of water supply can be saved after optimization, indicating that the developed model tends to allocate water in a more efficient way. The ratio of surface water to groundwater is reduced from 2:1 to 1.62:1. The proposed model has practical relevance for saving water and alleviating groundwater overexploitation. The approach is applicable to most areas with severe water shortages and groundwater overexploitation, and decision makers can determine the appropriate options for water resources allocation based on risk preferences and actual conditions. [ABSTRACT FROM AUTHOR]
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- 2018
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13. Projecting potential spatial and temporal changes in the distribution of Plasmodium vivax and Plasmodium falciparum malaria in China with climate change.
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Hundessa, Samuel, Williams, Gail, Li, Shanshan, Liu, De Li, Cao, Wei, Ren, Hongyan, Guo, Jinpeng, Gasparrini, Antonio, Ebi, Kristie, Zhang, Wenyi, and Guo, Yuming
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DRUG resistance , *PLASMODIUM falciparum , *TEMPORAL integration , *TWENTY-first century ,MALARIA transmission - Abstract
Background Global climate change is likely to increase the geographic range and seasonality of malaria transmission. Areas suitable for distribution of malaria vectors are predicted to increase with climate change but evidence is limited on future distribution of malaria with climate in China. Objective Our aim was to assess a potential effect of climate change on Plasmodium vivax ( P . vivax ) and Plasmodium falciparum ( P . falciparum ) malaria under climate change scenarios. Methods National malaria surveillance data during 2005–2014 were integrated with corresponding climate data to model current weather-malaria relationship. We used the Generalized Additive Model (GAM) with a spatial component, assuming a quasi-Poisson distribution and including an offset for the population while accounting for potential non-linearity and long-term trend. The association was applied to future climate to project county-level malaria distribution using ensembles of Global Climate Models under two climate scenarios - Representative Concentration Pathways (RCP4.5 and RCP8.5). Results Climate change could substantially increase P . vivax and P . falciparum malaria, under both climate scenarios, but by larger amount under RCP8.5, compared to the baseline. P . falciparum is projected to increase more than P . vivax . The distributions of P . vivax and P . falciparum malaria are expected to increase in most regions regardless of the climate scenarios. A high percentage (>50%) increases are projected in some counties of the northwest, north, northeast, including northern tip of the northeast China, with a clearer spatial change for P . vivax than P . falciparum under both scenarios, highlighting potential changes in the latitudinal extent of the malaria. Conclusion Our findings suggest that spatial and temporal distribution of P . vivax and P . falciparum malaria in China will change due to future climate change, if there is no policy to mitigate it. These findings are important to guide the malaria elimination goal for China. [ABSTRACT FROM AUTHOR]
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- 2018
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14. Climate change impact assessment on the hydrological regime of the Kaligandaki Basin, Nepal.
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Bajracharya, Ajay Ratna, Bajracharya, Sagar Ratna, Shrestha, Arun Bhakta, and Maharjan, Sudan Bikash
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WATERSHEDS , *CLIMATE change , *WATER balance (Hydrology) , *METEOROLOGICAL precipitation , *ATMOSPHERIC temperature , *HYDROLOGY - Abstract
The Hindu Kush-Himalayan region is an important global freshwater resource. The hydrological regime of the region is vulnerable to climatic variations, especially precipitation and temperature. In our study, we modelled the impact of climate change on the water balance and hydrological regime of the snow dominated Kaligandaki Basin. The Soil and Water Assessment Tool (SWAT) was used for a future projection of changes in the hydrological regime of the Kaligandaki basin based on Representative Concentration Pathways Scenarios (RCP 4.5 and RCP 8.5) of ensemble downscaled Coupled Model Intercomparison Project's (CMIP5) General Circulation Model (GCM) outputs. It is predicted to be a rise in the average annual temperature of over 4 °C, and an increase in the average annual precipitation of over 26% by the end of the 21st century under RCP 8.5 scenario. Modeling results show these will lead to significant changes in the basin's water balance and hydrological regime. In particular, a 50% increase in discharge is expected at the outlet of the basin. Snowmelt contribution will largely be affected by climate change, and it is projected to increase by 90% by 2090.Water availability in the basin is not likely to decrease during the 21st century. The study demonstrates that the important water balance components of snowmelt, evapotranspiration, and water yield at higher elevations in the upper and middle sub-basins of the Kaligandaki Basin will be most affected by the increasing temperatures and precipitation. [ABSTRACT FROM AUTHOR]
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- 2018
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15. Future changes over the Himalayas: Mean temperature.
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Dimri, A.P., Kumar, D., Choudhary, A., and Maharana, P.
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ATMOSPHERIC temperature , *CLIMATOLOGY , *GREENHOUSE gases , *RADIATIVE forcing - Abstract
An assessment of the projection of near surface air temperature over the Himalayan region from the COordinated Regional Climate Downscaling EXperiment- South Asia (hereafter, CORDEX-SA) regional climate model (RCM) experiments have been carried out for different Representative Concentration Pathway (RCP) scenarios. The purpose of this study is to assess the probable future changes in the mean temperature climatology and its long term trend for different seasons under greenhouse gas forcing scenarios for different seasons till the end of 21st century. A number of statistical measures such as changes in mean climatology, long term trend and probability distribution function have been used in order to detect the signals of changes in climate. Moreover, the associated uncertainties among different model experiments and their ensemble in space, time and different seasons in particular have been quantified. Despite of strong cold bias in the model experiments over Himalayan region (Nengker et al., 2017), statistically significant strong rate of warming (0.03–0.09 °C/year) across all the seasons and RCPs have been projected by all the models and their ensemble. Season specific response towards the warming is indicated by ensemble under future climate while ON season shows comparable magnitude of warming than DJF. Such warming intensifies with the increase in the radiative forcing under a range of greenhouse gas scenarios from RCP2.6 to RCP8.5. In addition to this, a wide range of spatial variability and disagreements in the trend magnitude between different models describes the uncertainty associated with the model projections and scenarios. A substantial seasonal response to warming with respect to elevation was also found, as DJF season followed by ON portrays highest rate of warming, specifically at higher elevation sites such as western Himalayas and northern part of central Himalayas. The different elevation classes respond differently to the projected future warming under different RCPs and seasons. Such higher warming during DJF may have consequences as changes in the fractional distribution of the solid and liquid precipitation as well as the melting of the glacial deposits with ultimately affecting the streamflow response and water resources in the downstream areas. [ABSTRACT FROM AUTHOR]
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- 2018
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16. Spatial variability of water-induced soil erosion under climate change and land use/cover dynamics: From assessing the past to foreseeing the future in the Mediterranean island of Crete.
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Polykretis, Christos, Grillakis, Manolis G., Manoudakis, Stelios, Seiradakis, Konstantinos D., and Alexakis, Dimitrios D.
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CLIMATE change , *SOIL erosion , *RAINFALL , *REMOTE-sensing images - Abstract
Climate change and land use/cover (LULC) changes are considered as main agents of soil erosion by water. Hence, evaluating both the past and future trends in rainfall and LULC patterns is crucial to seek their multi-temporal impacts on the erosion. In this line, the main objective of the present study was to assess the past and project the future variabilities of water-induced soil erosion under changes in rainfall and LULC patterns for the Mediterranean island of Crete (Greece). They were based on the estimation of soil loss rate by the GIS-based empirical model of RUSLE, and referred to three past periods (1991–2000, 2001–2010 and 2011–2020) and four periods of near and far future (2021–2030, 2031–2040, 2041–2050 and 2051–2100) under three different climate change scenarios (RCP2.6, RCP4.5 and RCP8.5). The relevant dynamics of R and C-factors incorporated in RUSLE were determined by using rainfall multi-historical observations and future simulations for the former, and LULC outputs derived from satellite images and CA-Markov model for the latter. The RUSLE outputs showed a gradual increase of mean soil loss during the past periods as a result of continuously increasing rainfall erosivity and bare land extent. However, the generally decreased levels projected for them in the future are expected to lead to a subsequent decrease of mean soil loss. In all cases, the mountainous parts of Crete and especially in the west were found to be more affected by erosion. Compared to the more recent past period of 2011–2020, the future period of 2041–2050 was projected to be the most notable in terms of potential risk, indicating the only scenario of increase (+0.4) in mean soil loss as well as the highest coverage (a total of 8 %) by areas of high and extreme loss. The RCP8.5 and RCP2.6 were projected to be the most negative climate change scenarios for the near (until 2040) and far (2040 onwards) future, respectively, presenting the smallest decreases (about −16 % and −5 %, respectively) in mean soil loss. The study's findings can offer knowledge indispensable for future sustainable policy-making and spatial planning. • Past/future assessments/projections of water-induced soil erosion in a Mediterranean island. • Under the impacts of climate and land use/cover changes. • Both climate and LULC changes seem to have an impact on soil erosion over time. • Projected soil erosion risk varies depending on the future period and climate change scenario (RCP). • The study fills a gap in terms of spatial scale, analyzing high-quality input datasets at regional scale. [ABSTRACT FROM AUTHOR]
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- 2023
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17. Global change scenarios in coastal river deltas and their sustainable development implications.
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Scown, Murray W., Dunn, Frances E., Dekker, Stefan C., van Vuuren, Detlef P., Karabil, Sitar, Sutanudjaja, Edwin H., Santos, Maria J., Minderhoud, Philip S.J., Garmestani, Ahjond S., and Middelkoop, Hans
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SUSTAINABLE development ,ABSOLUTE sea level change ,LAND subsidence ,RIVER sediments ,GEOLOGIC hot spots ,WATERSHEDS - Abstract
• Deltas are important places for global sustainable development. • Various environmental and developmental pressures place deltas at risk. • Global change scenarios suggest pressures will increase well beyond 2030. • Asian and some African deltas face large challenges but other deltas are not immune. • Humans have agency to mitigate key pressures from local to global scales. Deltas play a critical role in the ambition to achieve global sustainable development given their relatively large shares in population and productive croplands, as well as their precarious low-lying position between upstream river basin development and rising seas. The large pressures on these systems risk undermining the persistence of delta societies, economies, and ecosystems. We analyse possible future development in 49 deltas around the globe under the Shared Socio-economic and Representative Concentration Pathways until 2100. Population density, urban fraction, and total and irrigated cropland fraction are three to twelve times greater in these deltas, on average, than in the rest of the world. Maximum river water discharges are projected to increase by 11–33 % and river sediment discharges are projected to decrease 26–37 % on average, depending on the scenario. Regional sea-level rise reaches almost 1.0 m by 2100 for certain deltas in the worst-case scenario, increasing to almost 2.0 m of relative rise considering land subsidence. Extreme sea levels could be much higher still—reaching over 4.0 m by 2100 for six of the 49 deltas analysed. Socio-economic conditions to support adaptation are the weakest among deltas with the greatest pressures, compounding the challenge of sustainable development. Asian and African deltas stand out as having heightened socio-economic challenges—huge population and land use pressures in most Asian deltas and the Nile delta; low capacity for adaptation in most African deltas and the Irrawaddy delta. Although, deltas in other parts of the world are not immune from these and other pressures, either. Because of unique pressures and processes operating in deltas, as in other "hotspots" such as small islands, mountains, and semi-arid areas, we recommend greater consideration and conceptualisation of environmental processes in global sustainable development agendas and in the Integrated Assessment Models used to guide global policy. [ABSTRACT FROM AUTHOR]
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- 2023
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18. Climate change impacts under CMIP5 RCP scenarios on water resources of the Kelantan River Basin, Malaysia.
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Tan, Mou Leong, Ibrahim, Ab Latif, Yusop, Zulkifli, Chua, Vivien P., and Chan, Ngai Weng
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CLIMATE change , *ENVIRONMENTAL impact analysis , *WATER supply , *STREAMFLOW , *RUNOFF - Abstract
This study aims to evaluate the potential impacts of climate change on water resources of the Kelantan River Basin in north-eastern Peninsular Malaysia using the Soil and Water Assessment Tool (SWAT) model. Thirty-six downscaled climate projections from five General Circulation Models (GCMs) under the three Representative Concentration Pathways (RCPs) 2.6, 4.5 and 8.5 scenarios for the periods of 2015–2044 and 2045–2074 were incorporated into the calibrated SWAT model. Differences of these scenarios were calculated by comparing to the 1975–2004 baseline period. Overall, the SWAT model performed well in monthly streamflow simulation, with the Nash-Sutcliffe efficiency values of 0.75 and 0.63 for calibration and validation, respectively. Based on the ensemble of five GCMs, the annual rainfall and maximum temperature are projected to increase by 1.2–8.7% and 0.6–2.1 °C, respectively. This corresponds to the increases in the annual streamflow (14.6–27.2%), evapotranspiration (0.3–2.7%), surface runoff (46.8–90.2%) and water yield (14.2–26.5%) components. The study shows an increase of monthly rainfall during the wet season, and decrease during the dry season. Therefore, the monthly streamflow and surface runoff are likely to increase significantly in November, December and January. In addition, slight decreases in the monthly water yield are found between June and October (1.9–8.9%) during the 2015–2044 period. These findings could act as a scientific reference to develop better climate adaptation strategies. [ABSTRACT FROM AUTHOR]
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- 2017
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19. Nonparametric temporal downscaling with event-based population generating algorithm for RCM daily precipitation to hourly: Model development and performance evaluation.
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Lee, Taesam and Park, Taewoong
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NONPARAMETRIC statistics , *CLIMATOLOGY , *CLIMATE change mathematical models , *K-nearest neighbor classification , *METEOROLOGICAL precipitation , *CLIMATE change - Abstract
It is critical to downscale temporally coarse GCM or RCM outputs (e.g., monthly or daily) to fine time scales, such as sub-daily or hourly. Recently, a temporal downscaling model employing a nonparametric framework (NTD) with k-nearest resampling and a genetic algorithm has been developed to preserve key statistics as well as the diurnal cycle. However, this model’s usage can be limited in estimating precipitation for design storms or floods because the key statistics of annual maximum precipitation (AMP), especially for longer hourly durations, present a systematic bias that cannot be preserved due to the discontinuity of multiday consecutive precipitation events in the downscaling procedure. In the current study, we develop an approach to downscale a consecutive daily precipitation at once focusing on the reproduction of AMP totals for different durations instead of day-by-day downscaling. The proposed model has been verified with the precipitation datasets for the 60 stations across South Korea over the period 1979–2005. Additionally, two validation studies were performed with the recent datasets of 2006–2014 and nearest neighbor stations. The verification and the two validation tests conclude that the population-based NTD (PNTD) model proposed in the current study is superior to the existing NTD model in preserving the key statistics of the observed AMP series and suitable for downscaling future climate scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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20. Évaluation de la prise en charge des sarcomes des tissus mous en Franche-Comté depuis l’instauration d’une réunion de concertation pluridisciplinaire au CHRU. À propos de 47 cas.
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Haddad, J., Kalbacher, E., Piccard, M., Aubry, S., Chaigneau, L., and Pauchot, J.
- Abstract
Résumé Buts de l’étude Une réunion de concertation pluridisciplinaire (RCP) dédiée à la prise en charge des sarcomes a été instaurée en Franche-Comté en 2010. Les buts de l’étude sont : (a) évaluer la prise en charge des sarcomes par confrontation à la revue de la littérature ; (b) évaluer l’influence de la RCP sur la prise en charge des sarcomes par les hôpitaux au niveau régional. Matériel et méthode Il s’agit d’une étude rétrospective unicentrique de 2010 à 2015 chez des patients présentant un sarcome des tissus mous périphériques et établie à partir d’une base de données NetSarc (Réseau national des sarcomes) et du dossier communicant de cancérologie. Une base de données CleanWeb ® spécialement dédiée est créée. Résultats Quarante-sept patients sont inclus : dix sarcomes au niveau du membre supérieur, quarante-sept patients ont été inclus, 26 au niveau des membres inférieurs, 11 au niveau du tronc. Quarante patients ont été opérés : dix hors CHRU, 28 en CHRU et deux en centre coordinateur. Quatre-vingt-dix pour cent des patients pris en charge au CHRU étaient conformes aux recommandations. Aucun patient opéré en dehors du CHRU ne bénéficiait d’une prise en charge conforme aux recommandations. On constate une augmentation du nombre de dossiers adressés par les hôpitaux hors CHRU discuté en RCP avant tout traitement. Conclusion La création d’une RCP dédiée au sarcome améliore la prise en charge de ces tumeurs et diminue les prises en charge inadaptées en sensibilisant les médecins au niveau régional. Summary Goals of study A multidisciplinary meeting (RCP) dedicated to the treatment of sarcoma was established in Franche-Comte in 2010. The goals of the study are: (a) To evaluate the treatment of sarcomas by confrontation with the existing literature; (b) To evaluate the influence of the multidisciplinary meeting on the management of sarcomas by hospitals at the regional level. Materials and Methods This is a retrospective single center study from 2010 to 2015 on patients with sarcoma and peripheral soft tissue drawn from a Netsarc database (National Network of sarcomas) and communicating cancer record. A database Cleanweb especially dedicated is created. Results Forty-seven patients were included: ten sarcomas at the upper member 26 to the lower limbs, 11 on the trunk. Forty patients were operated on: ten out of the university hospital, 28 at the university hospital and two in a coordinating center. Ninety percent of patients treated at the university hospital were in accordance with the recommandations. None of the patients operated out of the university hospital benefited from medical care in accordance to the recommendations. There is an increase in the number of files sent by the hospitals out of the university hospital discussed in multidisciplinary meeting, before treatment. Conclusion The creation of a dedicated multidisciplinary meeting sarcoma improves the medical management of these tumors and decreases inappropriate medical managements thanks to a better education of the regional physicians. [ABSTRACT FROM AUTHOR]
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- 2017
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21. Potential geographic shifts in the coral reef ecosystem under climate change.
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Chaudhary, Chhaya, Alfaro-Lucas, Joan M., Simões, Marianna V.P., Brandt, Angelika, and Saeedi, Hanieh
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CORAL reefs & islands , *CORALS , *CLIMATE change models , *CORAL bleaching , *ECOSYSTEMS , *GLOBAL warming , *CLIMATE change , *TEMPERATE climate - Abstract
• We predicted habitat suitability shifts in the coral reef ecosystem under warming. • Nearly 90% of the warm water species studied would lose their tropical habitat. • An increase in generalists and a decrease in stenothermal species is expected. • We can expect a northward suitability shift in the northern hemisphere. • Such shifts may destabilise the coral reef ecosystem in the warmer future. The coral reefs are the most diverse marine ecosystem in the world. Considering its contribution as a natural resource for humanity and global biodiversity, it is critical to understand its response to climatic change. To date, no global predictions have been made about potential ecosystem changes in relation to its inhabiting species. Predicting changes in species' climatic suitability under increasing temperature and comparing them among species would be the first step in understanding the geographic and taxonomic coherence and discrepancies that may occur within the ecosystem. Using 57 species-specific global climate suitability models (of corals, molluscs, fish, crustaceans, and polychaetes) under present and future climate scenarios (RCP 4.5 and 8.5), we compared the potential coherence and differences and their cumulative impact on the ecosystem in warm, cold, shallow, and deep waters. Under the climatic scenarios, nearly 90% of 30 warm-water species were predicted to lose their suitability in the parts of the Indo-west Pacific, the Coast of Northern Australia, the South China Sea, the Caribbean Sea, and the Gulf of Mexico, resulting in the overall southward shift in their distributions. In contrast, a mixed response occurred in 27 cold-water species, with most northern temperate/boreal ones increasing their suitability in the Arctic Ocean and the Arctic species declining overall. We noticed that irrespective of their taxonomic group, the species with wider distribution ranges (thermal and geographic) had larger predicted gains in their suitability than their stenothermal counterparts, suggesting an increase of generalist species and a decline of specialist (endemic) species of the ecosystem under a warming climate. Our coherent projections of species' climatic suitability in warm and cold habitats of the tropics, temperate, boreal, and the Arctic, represent significant taxonomic groups of the ecosystem. This might indicate mass extinction risk (local– in the tropics and northern temperate regions, and overall– in the Arctic) in native habitats and a high species turnover across the ecosystem under a warming climate. This may also destabilise predator–prey dynamics in the ecosystem, especially if foraging specialists dominate coral food webs and adversely affect the associated countries. Our global projections highlight the regions of species' potential loss and gain; stakeholders could use the information to protect biodiversity and maintain human well-being. [ABSTRACT FROM AUTHOR]
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- 2023
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22. Assessing future availability of water resources in Taiwan based on the Budyko framework.
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Lee, Tsung-Yu, Chiu, Chi-Cheng, Chen, Chia-Jeng, Lin, Chuan-Yao, and Shiah, Fuh-Kwo
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CLIMATE change models , *WATER supply , *CLIMATE change mitigation , *SUSTAINABLE development , *PRECIPITATION gauges , *TYPHOONS , *CLUSTER analysis (Statistics) - Abstract
[Display omitted] • The Budyko framework was applied to 75 catchments covering a large area of Taiwan. • Varied landscape effects determined water resources availability among catchments. • Considerable spatial variability in the Budyko-related variables were found. • Three clusters were identified based on catchments' movements in the Budyko space. • 64 catchments will face the reduced availability of future water resources. Assessing water resources availability in a changing climate is a determinant of promoting sustainable development in a region. Such assessment should better be inter-basin in order to unveil a region's overall risk, so a time-varying Budyko framework is developed and adopted in this study. Gauge-based gridded precipitation and temperature, in company with runoff data, were used to derive the Budyko curves for 75 catchments over Taiwan. Downscaled precipitation and temperature data from selected global climate models and Representative Concentration Pathways (RCPs) were then used to calculate the shifts in the Budyko space of each catchment. It was found that the Budyko-related variables (e.g., evaporative and aridity indices, and catchment-specific parameter) exhibited considerable variability island-wide, with a few outliers in certain catchments being modulated by distinct landscape features and/or human activities. Under all RCPs analyzed, the majority of catchments showed the magnified movement vectors pointing at the 1st quadrant in the Budyko space in the late-21st century, suggesting a predominant and aggravating drying trend over Taiwan. Cluster analysis of the movement vectors under RCP8.5, which entailed the least inter-model differences, identified three major clusters, two of which (64 catchments included) indicated a drying trend of varied significancy. According to our findings, without effective mitigation of climate change, an increased likelihood of the worst-case scenario will substantialize the reduced availability of Taiwan's water resources. [ABSTRACT FROM AUTHOR]
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- 2023
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23. The Shared Socioeconomic Pathways and their energy, land use, and greenhouse gas emissions implications: An overview.
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Riahi, Keywan, van Vuuren, Detlef P., Kriegler, Elmar, Edmonds, Jae, O’Neill, Brian C., Fujimori, Shinichiro, Bauer, Nico, Calvin, Katherine, Dellink, Rob, Fricko, Oliver, Lutz, Wolfgang, Popp, Alexander, Cuaresma, Jesus Crespo, KC, Samir, Leimbach, Marian, Jiang, Leiwen, Kram, Tom, Rao, Shilpa, Emmerling, Johannes, and Ebi, Kristie
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ENERGY consumption ,LAND use ,GREENHOUSE gases & the environment ,ENVIRONMENTAL impact analysis ,SUSTAINABLE development - Abstract
This paper presents the overview of the Shared Socioeconomic Pathways (SSPs) and their energy, land use, and emissions implications. The SSPs are part of a new scenario framework, established by the climate change research community in order to facilitate the integrated analysis of future climate impacts, vulnerabilities, adaptation, and mitigation. The pathways were developed over the last years as a joint community effort and describe plausible major global developments that together would lead in the future to different challenges for mitigation and adaptation to climate change. The SSPs are based on five narratives describing alternative socio-economic developments, including sustainable development, regional rivalry, inequality, fossil-fueled development, and middle-of-the-road development. The long-term demographic and economic projections of the SSPs depict a wide uncertainty range consistent with the scenario literature. A multi-model approach was used for the elaboration of the energy, land-use and the emissions trajectories of SSP-based scenarios. The baseline scenarios lead to global energy consumption of 400–1200 EJ in 2100, and feature vastly different land-use dynamics, ranging from a possible reduction in cropland area up to a massive expansion by more than 700 million hectares by 2100. The associated annual CO 2 emissions of the baseline scenarios range from about 25 GtCO 2 to more than 120 GtCO 2 per year by 2100. With respect to mitigation, we find that associated costs strongly depend on three factors: (1) the policy assumptions, (2) the socio-economic narrative, and (3) the stringency of the target. The carbon price for reaching the target of 2.6 W/m 2 that is consistent with a temperature change limit of 2 °C, differs in our analysis thus by about a factor of three across the SSP marker scenarios. Moreover, many models could not reach this target from the SSPs with high mitigation challenges. While the SSPs were designed to represent different mitigation and adaptation challenges, the resulting narratives and quantifications span a wide range of different futures broadly representative of the current literature. This allows their subsequent use and development in new assessments and research projects. Critical next steps for the community scenario process will, among others, involve regional and sectoral extensions, further elaboration of the adaptation and impacts dimension, as well as employing the SSP scenarios with the new generation of earth system models as part of the 6th climate model intercomparison project (CMIP6). [ABSTRACT FROM AUTHOR]
- Published
- 2017
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24. An evaluation of thermowell’s integrity in RCP test facility.
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Kim, Yeon-Sik, Kim, Bok-Deuk, Youn, Young-Joong, Jeon, Woo-Jin, Kim, Seok, Bae, Byoung-Uhn, Cho, Yun-Je, Cho, Seok, and Hwang, Jong-Keun
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OSCILLATIONS , *MODAL analysis , *NUCLEAR reactor cooling , *SURFACES (Technology) , *FRACTURE mechanics - Abstract
An RCP test facility has been constructed at KAERI. During the commissioning startup operation, one of thermowells was cracked due to the high-speed coolant velocity. To complete the startup operation, a modified design of the thermowells was proposed, and all the original thermowells were replaced by the modified ones. From an evaluation of the original and modified designs of the thermowells according to the recent PTC code, the original design did not satisfy the new or old requirements, and the modified design simply satisfied the old requirement. The cracked surface of the original one was owing to the fatigue stresses in transverse oscillations. Two of three modified thermowells were found to be bent after about a 4.1 × 10 8 fatigue cycle operation. Their tapered-shanks came in contact with the nozzle walls and each showed a rim of deformation on the root. The modified ones suffered the fatigue stresses in in-line oscillations and became bent in in-line direction. A new design of thermowells with a straight shape and shorter unsupported length satisfying the current PTC code requirement was developed and installed in the RCP test facility. For the new design, additional modal analysis based on the finite element method was performed to check the dynamic behaviors using the ANSYS code and it was found that the PTC code predicted more conservative frequencies for the evaluation of dynamic behaviors in thermowell design. [ABSTRACT FROM AUTHOR]
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- 2016
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25. Multi-step prediction of main pump leakage in nuclear power plants with an additive model.
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Xiao, Yang, Liu, Jie, and Su, Qing
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NUCLEAR power plants , *HILBERT-Huang transform , *STANDARD deviations , *NUCLEAR industry - Abstract
With the global demand of clean and low-carbon emission energy sources, safety in the nuclear power industry has gained widespread attention. The accurate and timely long-term fault prognostics of critical equipment in nuclear power plants (NPPs) helps to effectively schedule maintenance, thus reducing operation and maintenance costs while ensuring safety. Unpredictable future load and operations make long-term prediction of time series data in NPPs quite challenging. In this study, we proposed a framework for multi-step prediction based on an empirical mode decomposition (EMD) algorithm, which decomposed complex time series data into several components with simple trends. The useful signal and noise in the components were then divided by a relative ratio method. Candidate prediction models from the model library were trained and tuned on the signal-dominated components. The appropriate model was selected for prediction according to the characteristics of each component signal, and the prediction results were summed and smoothed with an additive model. The proposed method, noted as the denoised EMD method using an additive method (EMD-AM), was applied to the leakage prediction at shaft seals in the reactor coolant pump (RCP) of five different NPPs. Root mean square error (RMSE), mean absolute percentage error (MAPE) and mean absolute scaled error (MASE) were selected to determine the prediction accuracy and uncertainty. Compared with EMD-AM and EMD method using long short-term memory (EMD-LSTM), the experimental results show that the denoised EMD-AM has the overall advantage of simplicity and accuracy. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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26. The non-uniform inflow structure of reactor coolant pump based on Laser Doppler Velocimetry.
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Song, Yu, Huang, Song, Xu, Rui, Zhang, Zhengchuan, Yin, Junlian, and Wang, Dezhong
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LASER Doppler velocimetry , *LASER pumping , *COOLANTS , *STEAM generators - Abstract
• Emphasize the effect of the non-uniform inflow on the performance of RCPs. • Build the non-uniform inflow structure with LDV measurement. • Illustrate and analyze the velocity distribution and turbulence intensity rate of inflow field. The hydrodynamic fields generated by the steam generator (SG) head at the reactor coolant pump (RCP) inlet are experimentally and numerically investigated in this paper. The velocity profiles and turbulence intensity rate were obtained with a Laser Doppler Velocimetry (LDV) system. The velocity profiles under non-uniform inflow and uniform inflow conditions were obtained and compared. The numerical results on measurement sections were qualitatively and quantitatively validated against LDV data. The results indicated that the numerical method have a good agreement with the experiments. It can be known from the study that hydraulic performance of pump deteriorates with its inflow. In addition, the velocity profile of non-uniform inflow can be divided into three regions. These regions are constant high velocity region, large velocity gradient region and back flow region respectively. Furtherly, from the turbulence intensity rate analysis, it can be concluded that the non-uniform inflow is highly turbulent, which would bring significant performance changes to the pump. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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27. Development of models for sustainable green mussel cultivation under climate change events.
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Srisunont, Chayarat, Srisunont, Treeranut, and Babel, Sandhya
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SUSTAINABLE development , *MUSSELS , *EXTREME weather , *WATER quality , *PHYTOPLANKTON populations , *CLIMATE change - Abstract
• Developed models can estimate mussel production during climate change events. • High RCP causes mussel mortality due to salinity reduction and thermal stress. • In all RCPs, the mussel productions were forecasted to decrease over time. • High mussel density is more sensitive to climate change than low mussel density. • Appropriate seedling and harvest periods can be forecasted using the model. This research developed a green mussel cultivation model to assist sustainable production for farmers under climate change events. The model consists of 4 sub-models: mussel growth, phytoplankton population, the effect of seawater quality on mussel density, and the influence of atmospheric parameters on seawater quality. The integrated model was constructed by STELLA software and was calibrated with field observation data. The model was employed to simulate the impact of climate change on mussels based on the Intergovernmental Panel on Climate Change: The Fifth Assessment Report (IPCC AR5) projection. Results demonstrated that mussel production varied due to differences in the available phytoplankton, the initial mussel weight, the cultivation period, the air temperature, and the rainfall pattern. The model simulations showed that under the greater radiative forcing scenario (Representative Concentration Pathways: RCPs), higher rainfall and air temperatures resulted in salinity reduction and thermal stress on green mussels. Consequently, mussel production was forecasted to decline over time. The simulations also revealed that during extreme weather events, low mussel density, high aeration, and being far from freshwater discharge could avoid mass mussel mortality. Using the results of the developed model, an appropriate cultivation period can be forecasted. However, it depends on the site-specific climate pattern in each cultivation area. Results can be employed as a climate change adaptation tool for mussel farmers. Finally, the information can assist other researchers interested in sustainable mussel cultivation under extreme events. [Display omitted] [ABSTRACT FROM AUTHOR]
- Published
- 2022
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28. Adaptation to climate change: The impacts of optimized planting dates on attainable maize yields under rainfed conditions in Burkina Faso.
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Waongo, M., Laux, P., and Kunstmann, H.
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CLIMATE change , *CORN breeding , *PLANTING , *DEVIATION (Statistics) , *AGRICULTURE - Abstract
The high intra-seasonal rainfall variability and the lack of adaptive capacities are the major limiting factors for rainfed agricultural production in smallholder farming systems across Sub-Saharan Africa. Therefore, the crop planting date, a low-cost agricultural management strategy aiming to alleviate crop water stress can contribute to enhance agricultural decision-making, particularly as a climate change adaptation strategy. By considering the crop water requirements throughout the crop growing cycle using a process-based crop model in conjunction with a fuzzy rule-based planting date approach, location-specific planting rules were derived for maize cropping in Burkina Faso (BF). Then, they were applied to regional future climate projections to derive optimized planting dates (OPDs) for the 2020s (2011–2030) and the 2040s (2031–2050), respectively. Based on potential maize yield simulations driven by climate change projections and planting dates, the OPD approach was compared with a well-established planting date method for West Africa and evaluated as a potential adaptation strategy for climate change. On average, the OPD approach achieved approximately +15% higher potential maize yield regardless of the regional climate model (RCM) and the period. However, the potential yield surpluses strongly decreased from the North to the South. Regarding climate change adaptation, the combined impact of climate change and the OPD approach has shown on average, a mean maize yield deviation between −23% and 34% in comparison to the 1989–2008 baseline period. Yield deviation is found to depend strongly on the RCM and location. The RCM ensemble mean yield for the period 2011–2050 revealed a maximum decrease of 8% compared to the baseline period. On the one hand, these findings highlight the potential of the OPDs as a crop management strategy but, on the other hand, it is apparent that farmers need to combine the OPDs with others suited farming practices to adequately respond to climate change. [ABSTRACT FROM AUTHOR]
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- 2015
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29. Structural, magnetic, and magnetocaloric properties of La0.7Sr0.2Nd0.1Mn1-xNixO3 (x= 0.05, 0.10, and 0.15): B-site doping.
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Xie, Zhuojia, Zou, Zhengguang, Jiang, Xinyu, Zhang, Weijian, He, Bangrong, Han, Xiangnan, and Mao, Zheng
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MAGNETOCALORIC effects , *MAGNETIC entropy , *MAGNETIC cooling , *MAGNETIC declination , *MAGNETIC materials , *CURIE temperature , *HEUSLER alloys - Abstract
In this study, La 0.7 Sr 0.2 Nd 0.1 Mn 1-x Ni x O 3 (x = 0.05, 0.10, 0.15) systems were synthesized following the sol-gel (SG) approach and their structural, magnetic, and magnetocaloric characteristics were determined. The X-ray Diffraction (XRD) patterns revealed that all samples were in the R-3c space group. Magnetic studies revealed that an increase in the Ni2+ dopant resulted in a ferromagnetic (FM) to paramagnetic (PM) transition near the Curie temperature (Tc), when Tc decreased from 280 K to 220 K. The maximum change in magnetic entropy (− Δ S M M a x ) gradually decreased while the relative cooling power (RCP) gradually increased. The − Δ S M M a x and RCP values for La 0.7 Sr 0.2 Nd 0.1 Mn 0.95 Ni 0.05 O 3 were 4.28 J/(kg·K) and 267.67 (J/kg), respectively at 280 K when the external magnetic field variation was 5 T. This material can potentially be one of the candidates for developing the magnetic refrigeration technology. • Tc of La 0.7 Sr 0.2 Nd 0.1 Mn 0.95 Ni 0.05 O 3 is nearer to room temperature. The Tc of La 0.7 Sr 0.2 Nd 0.1 Mn 0.95 Ni 0.05 O 3 sample is 280 K. • La 0.7 Sr 0.2 Nd 0.1 Mn 0.95 Ni 0.05 O 3 has a -Δ S M of 4.28 J/kg K at a temperature of 280 K, and its RCP is 267.67 J/kg under 5T. • We know that LSNMNO samples have a large magnetic entropy change and RCP compared to other magnetic materials. [ABSTRACT FROM AUTHOR]
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- 2022
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30. Future ozone and oxidants change under the RCP scenarios.
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Kim, Minjoong J., Park, Rokjin J., Ho, Chang-Hoi, Woo, Jung-Hun, Choi, Ki-Chul, Song, Chang-Keun, and Lee, Jae-Bum
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OZONE , *OXIDIZING agents , *AIR quality , *CLIMATE change , *EMISSIONS (Air pollution) , *CHEMICAL precursors - Abstract
We investigate ozone air quality changes in 2050 caused by global changes in climate and anthropogenic emissions of ozone precursors by using a global chemical transport model driven by meteorological fields from a general circulation model. We use projected emissions based on the Representative Concentration Pathway (RCP) scenarios and conduct model simulations to quantify the effects of climate and emission changes on future air quality, focusing on ozone in surface air. Our model results show that annual mean concentrations of surface ozone will be lower in 2050 relative to 2000 by −3.3, −3.7, and −4.2 ppbv under RCP6.0, RCP4.5, and RCP2.6, respectively. In contrast, the RCP8.5 projection results in a slight increase of 2.1 ppbv caused by a methane increase. The ozone reductions are driven primarily by decreases in NO x emission, which dominate the climate penalty on ozone driven by temperature increases. We also estimate the effect of 21st century climate change on ozone air quality, assuming no changes in anthropogenic emissions of ozone precursors in the future. We further use a statistical method to analyze the results in order to quantify the effect of each meteorological variable change on ozone concentration in summer. Temperature increase is found to result in ozone increases of up to 2.2 ppbv over land. Ozone over the oceans, however, is largely reduced with specific humidity increase, particularly in the Northern Hemisphere, where the ozone concentration decreases by 0.8 ppbv. We find that future increases in natural NO x emissions from lightning and soil make an important contribution to the formation of nitric acid and might seriously offset future decreases in nitrogen deposition caused by anthropogenic NO x emission reduction. [ABSTRACT FROM AUTHOR]
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- 2015
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31. Global wheat production potentials and management flexibility under the representative concentration pathways.
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Balkovič, Juraj, van der Velde, Marijn, Skalský, Rastislav, Xiong, Wei, Folberth, Christian, Khabarov, Nikolay, Smirnov, Alexey, Mueller, Nathaniel D., and Obersteiner, Michael
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WHEAT products , *AGRICULTURAL productivity , *FOOD security , *CROP management , *WHEAT yields , *CLIMATE change , *IRRIGATION - Abstract
Wheat is the third largest crop globally and an essential source of calories in human diets. Maintaining and increasing global wheat production is therefore strongly linked to food security. A large geographic variation in wheat yields across similar climates points to sizeable yield gaps in many nations, and indicates a regionally variable flexibility to increase wheat production. Wheat is particularly sensitive to a changing climate thus limiting management opportunities to enable (sustainable) intensification with potentially significant implications for future wheat production. We present a comprehensive global evaluation of future wheat yields and production under distinct Representative Concentration Pathways (RCPs) using the Environmental Policy Integrated Climate (EPIC) agro-ecosystem model. We project, in a geographically explicit manner, future wheat production pathways for rainfed and irrigated wheat systems. We explore agricultural management flexibility by quantifying the development of wheat yield potentials under current, rainfed, exploitable (given current irrigation infrastructure), and irrigated intensification levels. Globally, because of climate change, wheat production under conventional management (around the year 2000) would decrease across all RCPs by 37 to 52 and 54 to 103 Mt in the 2050s and 2090s, respectively. However, the exploitable and potential production gap will stay above 350 and 580 Mt, respectively, for all RCPs and time horizons, indicating that negative impacts of climate change can globally be offset by adequate intensification using currently existing irrigation infrastructure and nutrient additions. Future world wheat production on cropland already under cultivation can be increased by ~ 35% through intensified fertilization and ~ 50% through increased fertilization and extended irrigation, if sufficient water would be available. Significant potential can still be exploited, especially in rainfed wheat systems in Russia, Eastern Europe and North America. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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32. Nonparametric statistical temporal downscaling of daily precipitation to hourly precipitation and implications for climate change scenarios.
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Lee, Taesam and Jeong, Changsam
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DOWNSCALING (Climatology) , *NONPARAMETRIC statistics , *METEOROLOGICAL precipitation , *RAINFALL , *GENETIC algorithms - Abstract
Highlights: [•] Develop a stochastic temporal downscaling model from daily rainfall to hourly. [•] Adopt Genetic Algorithm to provide new temporal patterns. [•] Downscale the daily precipitation of observed and RCP 4.5 and 8.5 data to hourly. [•] Compare the statistical characteristics between the observed and downscaled data. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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33. Equilibrium-based reconstruction of three-dimensional stresses in GBT.
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de Miranda, Stefano, Gutierrez, Alejandro, and Miletta, Rosario
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MATHEMATICAL models , *GIRDERS , *EQUILIBRIUM , *THREE-dimensional imaging , *STRAINS & stresses (Mechanics) , *STRUCTURAL plates , *BOUNDARY value problems - Abstract
Abstract: In this paper, a procedure for a posteriori reconstruction of three-dimensional stresses in the finite element analysis of beams modelled within the framework of the Generalized Beam Theory is presented. The reconstruction is based on the enforcement of the pointwise three-dimensional equilibrium equations over the beam, interpreted as an assembly of thick plates, and on the use of the Recovery by Compatibility in Patches procedure. No corrections to meet the equilibrium boundary conditions on bottom/top wall faces are needed. Numerical results show that the proposed approach allows to effectively recover local stress profiles which match those of three-dimensional solid finite element models. [Copyright &y& Elsevier]
- Published
- 2014
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34. Projected trends in mean, maximum, and minimum surface temperature in China from simulations.
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You, Qinglong, Min, Jinzhong, Fraedrich, Klaus, Zhang, Wei, Kang, Shichang, Zhang, Ling, and Meng, Xianhong
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LAND surface temperature , *CLIMATE change , *GREENHOUSE gases , *GLOBAL warming , *SIMULATION methods & models - Abstract
This study examines the projected characteristics of mean temperature (Tmean), maximum temperature (Tmax) and minimum temperature (Tmin) in China during 2006–2100 from simulations of MPI-ESM-LR model within the Coupled Model Intercomparison Project Phase 5 (CMIP5). Periods of 2011–2040 and 2061–2090 are concentrated on the analysis under the three representative concentration pathway (RCP) scenarios: a high emission scenario (RCP8.5), a midrange mitigation emission scenario (RCP4.5), and a low emission scenario (RCP2.6). Under RCP8.5, the Tmean, Tmax and Tmin show pronounced warming with the annual rates of 0.43°C/decade, 0.42°C/decade, 0.45°C/decade during 2011–2040, and 0.72°C/decade, 0.70°C/decade, 0.76°C/decade during 2061–2090, which pronouncedly contributed by winter. Under RCP4.5, the Tmean, Tmax and Tmin display consistent increases during 2011–2040 with the trends of 0.29°C/decade, 0.29°C/decade, 0.30°C/decade on the annual basis, respectively, and the increases calm down for Tmean, Tmax and Tmin up to 0.14°C/decade during 2061–2090. Under RCP2.6, the Tmean, Tmax and Tmin demonstrate positive trends during 2011–2040 with the annual rates of 0.26°C/decade, 0.28°C/decade, 0.25°C/decade, respectively, and turn to negative afterwards. Moreover, the annual and seasonal Tmean, Tmax and Tmin are in agreement with the concentration of greenhouse gases in the atmosphere and reflect the variability of the radiative forcing trajectories in the RCP. For the spatial patterns, the northeastern China and the Tibetan Plateau are more sensitive and susceptible to climate change in future emission scenarios. It fails to capture the asymmetric trends for Tmax and Tmin projections, which do exist in the observations on the regional and global scales. This suggests that the projections have uncertainties in the models, and an understanding of causes is essential to improve the accuracies. [ABSTRACT FROM AUTHOR]
- Published
- 2014
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35. Impacts of changes in climate and land use/land cover under IPCC RCP scenarios on streamflow in the Hoeya River Basin, Korea.
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Kim, Jinsoo, Choi, Jisun, Choi, Chuluong, and Park, Soyoung
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CLIMATE change , *LAND use , *LAND cover , *STREAMFLOW , *CLIMATOLOGY , *RUNOFF - Abstract
Abstract: This study examined the separate and combined impacts of future changes in climate and land use/land cover (LULC) on streamflow in the Hoeya River Basin, South Korea, using the representative concentration pathway (RCP) 4.5 and 8.5 scenarios of the Fifth Assessment Report (AR5) of the Intergovernmental Panel on Climate Change (IPCC). First, a LULC change model was developed using RCP 4.5 and RCP 8.5 storylines and logistic regression. Three scenarios (climate change only, LULC change only, and climate and LULC change combined) were established, and the streamflow in future periods under these scenarios was simulated by the Soil and Water Assessment Tool (SWAT) model. Each scenario showed distinct seasonal variations in streamflow. Under climate change only, streamflow increased in spring and winter but decreased in summer and autumn, whereas LULC change increased high flow during wet periods but decreased low flow in dry periods. Although the LULC change had less effect than climate change on the changes in streamflow, the effect of LULC change on streamflow was significant. The result for the combined scenario was similar to that of the climate change only scenario, but with larger seasonal changes in streamflow. Although the effects of LULC change were smaller than those caused by climate change, LULC changes may heighten the problems of increased seasonal variability in streamflow caused by climate change. The results obtained in this study provide further insight into the availability of future streamflow and can aid in water resource management planning in the study area. [Copyright &y& Elsevier]
- Published
- 2013
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36. Influence Of Copper And Zinc On The Power Furring Of Encrusting Water.
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Ras, Hadda.Semine and Ghizellaoui, Samira.
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CALCAREOUS soils ,INCRUSTATIONS ,METAL content of water ,CALCIUM carbonate ,WATER distribution ,POLYETHYLENE - Abstract
Abstract: In calcareous soils, the underground water of Hamma carry significant concentrations of calcium hydrogencarbonate. For a content of 59 ¡ F waters were very hard and out have to be in a treated softening way or decarbonation before the use, because lead to phenomenes of scaling. The precipitation of an insulating layer of calcium carbonate on the walls of the water distribution have serious consequences technique and economic. In this work we studied the effect of copper and zinc on the precipitation of calcium carbonate by using the test of rapid controlled precipitation (RCP) and scaling tests on polyethylene. The test of rapid precipitation controlled in the presence of metal cations (Cu, Zn) at low concentrations (0.5mg/L of Cu
2+ , 0.15mg/L of Zn2+ ), retarted the precipitation of calcium carbonate.The test of scaling on polyethylene in the presence of Cu and Zn reached an efficiency of 100%. This reflects the pronounced inhibitory effect of these ions. [Copyright &y& Elsevier]- Published
- 2012
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37. A life cycle based environmental impacts assessment of construction materials used in road construction.
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Chowdhury, Raja, Apul, Defne, and Fry, Tim
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ENVIRONMENTAL impact analysis ,ROAD construction equipment & supplies ,MINERAL aggregates ,WASTE products as road materials ,CONCRETE pavement recycling ,FLY ash ,COAL ash ,POLLUTANTS ,TOXICOLOGY - Abstract
Abstract: Industrial byproducts such as coal fly ash, coal bottom ash, and recycled concrete pavement (RCP) are being used in considerable amounts as a full or partial replacement of natural aggregates. Studies comparing road construction byproduct materials with natural aggregates are limited. In the present study, a comparison of these byproducts with natural aggregates was carried out with respect to cost, environmental pollutants generated, and energy consumption. Pollutant emission data were aggregated to express results in terms of global warming potential (GWP), acidification potential and various toxicity potentials. For assessment of toxicity potentials, all the toxicities were represented with respect to 1,4 dichlorobenzene. Mixed results were found from the Life Cycle Assessment (LCA) and no single material performed superiorly in all categories. Fly ash and bottom ash were found attractive in cost, GWP, and acidification potential categories. RCP had higher GWP and acidification potential compared to natural aggregates. In toxicity categories, in some cases fly ash and bottom ash had higher; and RCP, in all cases, had much lower toxicity compared to natural aggregates. [Copyright &y& Elsevier]
- Published
- 2010
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38. The Rab11-FIP1/RCP gene codes for multiple protein transcripts related to the plasma membrane recycling system
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Jin, Min and Goldenring, James R.
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HUMAN genetics , *GENETICS , *CELL membranes , *PROTEINS - Abstract
Abstract: Rab11a is a member of the Rab11 small GTPase family, and plays an important role in plasma membrane recycling. Rab11-Family Interacting Protein 1 (Rab11-FIP1) binds to Rab11 through a carboxyl-terminal amphipathic alpha helix. We have identified eight alternatively spliced Rab11-FIP1 gene transcripts from human chromosome 8. Among them, Rab11-FIP1A-D have carboxyl terminal Rab11 binding domains, while Rab11-FIP1E-H do not contain the Rab11 binding domain. While Rab11-FIP1B and F gene transcripts are ubiquitous, other Rab11-FIP1 transcripts demonstrate more limited patterns of expression in human tissue cDNAs. EGFP-Rab11-FIP1A-D proteins over-expressed in HeLa cells targeted to Rab11a-containing membranes, while EGFP-Rab11-FIP1E/F and H proteins did not localize with recycling system membranes. However, transferrin trafficking was not significantly altered in HeLa cells over-expressing expressing any of the EGFP-Rab11-FIP1 proteins. Rabbit polyclonal antibodies specific for Rab11-FIP1B and Rab11-FIP1C/RCP demonstrated that Rab11-FIP1B and Rab11-FIP1C/RCP are expressed endogenously. Strikingly, endogenous staining for Rab11-FIP1C/RCP only partially co-localized with EGFP-Rab11-FIP1A, EGFP-Rab11-FIP1B, and EGFP-Rab11a in the perinuclear region, indicating that Rab11-FIP1C/RCP resides in a differentiable subcellular compartment within the plasma membrane recycling system compared with Rab11-FIP1A and Rab11-FIP1B. These data suggest that Rab11-FIP1 proteins may play coordinated roles in regulating plasma membrane recycling with regional specificity within the Rab11a-containing recycling system. [Copyright &y& Elsevier]
- Published
- 2006
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39. Specimen temperature conditioning and drift before an S4 pipe fracture test
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Leevers, P.S., Hillmansen, S., and de F.F. Moreno, L.
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POLYETHYLENE , *THERMOPLASTICS , *PLASTICS , *PIPE , *TEMPERATURE - Abstract
The resistance of plastic (primarily polyethylene) pipe to rapid axial crack propagation under pressure is specified using the ISO 13477 ‘S4’ (small-scale steady state) test method. Pipe performance in this test may be very sensitive to temperature under standard test conditions. There has recently been concern that the temperature conditioning of pipe specimens required by ISO 13477 may not be sufficiently precise. In order to compensate for an over-estimated increase in surface temperature between removal from the conditioning fluid and testing, some laboratories condition specimens well below the test temperature. Here, infra-red imaging data are used to calibrate a simple and conservative model for the evolution of surface temperature during this interval. The results broadly support the present specification for testing at 0 °C, and provide a more secure basis for conditioning of specimens to be tested at lower temperatures. [Copyright &y& Elsevier]
- Published
- 2004
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40. A pilot randomised trial of thrombolysis in cardiac arrest (The TICA trial)
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Fatovich, Daniel M., Dobb, Geoffrey J., and Clugston, Richard A.
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THROMBOLYTIC therapy , *CARDIAC arrest , *VENTRICULAR fibrillation , *PLACEBOS , *FIBRINOLYTIC agents , *TISSUE plasminogen activator , *COMPARATIVE studies , *CARDIOPULMONARY resuscitation , *HOSPITAL emergency services , *RESEARCH methodology , *MEDICAL cooperation , *RESEARCH , *STATISTICAL sampling , *SURVIVAL , *PILOT projects , *EVALUATION research , *RANDOMIZED controlled trials , *BLIND experiment , *THERAPEUTICS - Abstract
Introduction: The outcome after out of hospital cardiac arrest is dismal. Thrombolysis during CPR has been advocated. Our hypothesis was that early administration of bolus thrombolysis could lead to improved survival from out of hospital cardiac arrest.Methods: A prospective, randomised, double blind placebo controlled trial. All victims of out of hospital cardiac arrest brought to the Emergency Department (ED) by the emergency medical system were eligible for inclusion. All patients received standard advanced cardiac life support, except that the first drug the patient received was either tenecteplase 50 mg or placebo. The primary end point was return of spontaneous circulation (ROSC).Results: Of 35 patients enrolled, 19 received tenecteplase and 16 placebo. The tenecteplase group was younger (63 vs 72 years P = 0.04) and had significantly more ventricular fibrillation as the initial rhythm (63% versus 19%, 44% difference, 95% CI 15-73%). There was no difference in rhythm on arrival at the ED. ROSC occurred in 8 (42%) patients receiving tenecteplase and one (6%) placebo (36% difference, 95% CI 11-61%). Two tenecteplase and one placebo patient survived to leave ED, and one in each group survived to hospital discharge. Autopsy results were available on eight patients, five of whom had a thrombotic cause of death.Conclusion: In this pilot study, we found the use of early bolus tenecteplase for OHCA to be feasible, and that it appears to increase the rate of ROSC. Larger studies are required to determine if this translates into a survival benefit. Appropriate patient selection for OHCA studies remains problematic. [ABSTRACT FROM AUTHOR]- Published
- 2004
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41. Oxygen delivery and return of spontaneous circulation with ventilation:compression ratio 2:30 versus chest compressions only CPR in pigs
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Dorph, E., Wik, L., Strømme, T.A., Eriksen, M., and Steen, P.A.
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PHYSIOLOGICAL transport of oxygen , *CARDIAC arrest , *ARTIFICIAL respiration , *CARDIOPULMONARY resuscitation - Abstract
The need for rescue breathing during the initial management of sudden cardiac arrest is currently being debated and reevaluated. The present study was designed to compare cerebral oxygen delivery during basic life support (BLS) by chest compressions only with chest compressions plus ventilation in pigs with an obstructed airway mimicked by a valve hindering passive inhalation. Resuscitability was then studied during the subsequent advanced life support (ALS) period. After 3 min of untreated ventricular fibrillation (VF) BLS was started. The animals were randomised into two groups. One group received chest compressions only. The other group received ventilations and chest compressions with a ratio of 2:30. A gas mixture of 17% oxygen and 4% carbon dioxide was used for ventilation during BLS. After 10 min of BLS, ALS was provided. All six pigs ventilated during BLS attained a return of spontaneous circulation (ROSC) within the first 2 min of advanced cardiopulmonary resuscitation (CPR) compared with only one of six compressions-only pigs. While all except one compressions-only animal achieved ROSC before the experiment was terminated, the median time to ROSC was shorter in the ventilated group. With a ventilation:compression ratio of 2:30 the arterial oxygen content stayed at 2/3 of normal, but with compressions-only, the arterial blood was virtually desaturated with no arterio-venous oxygen difference within 1.5–2 min. Haemodynamic data did not differ between the groups. In this model of very ideal BLS, ventilation improved arterial oxygenation and the median time to ROSC was shorter. We believe that in cardiac arrest with an obstructed airway, pulmonary ventilation should still be strongly recommended. [Copyright &y& Elsevier]
- Published
- 2004
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42. Compared to angiotensin II, epinephrine is associated with high myocardial blood flow following return of spontaneous circulation after cardiac arrest
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Little, Charles M., Angelos, Mark G., and Paradis, Norman A.
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ADRENALINE , *VASOPRESSIN , *ANGIOTENSINS , *BLOOD flow - Abstract
Introduction: Epinephrine (adrenaline) and vasopressin are used currently to improve myocardial blood flow (MBF) during cardiac arrest. Angiotensin II has also been shown to improve MBF during CPR. We explored the effects of angiotensin II or epinephrine alone, and the combination of angiotensin with epinephrine, on myocardial and cerebral blood flows in a swine model of cardiac arrest. Methods: Swine were instrumented for regional blood flow measurements. Ventricular fibrillation was induced and CPR begun. Angiotensin II 50 mcg/kg (ANG), epinephrine 0.02 mg/kg (EPI) or the combination (ANG+EPI) was administered. Blood flow was measured during baseline normal sinus rhythm (NSR), before (CPR) and after drug administration (CPR+DRUG), and post reperfusion return of spontaneous circulation (ROSC). Results: All groups had a significant increase in MBF during CPR following drug administration (P<0.05).
There was a trend toward higher flows in the EPI groups. The group receiving both EPI and ANG did not have higher blood flows than the EPI or ANG alone groups. Both groups that received EPI had markedly elevated MBF following ROSC compared with angiotensin II (P<0.05). Conclusions: The combination of ANG and EPI did not improve MBF during cardiac arrest. Epinephrine may increase MBF compared with angiotensin II post-reperfusion. [Copyright &y& Elsevier]MBF ANG EPI ANG+EPI NSR 134±37 192±123 155±70 CPR 13±19 2±4 1±2 CPR+DRUG 63±64 82±54 81±84 ROSC 213±58 988±454 938±542 - Published
- 2003
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43. Quality of CPR with three different ventilation:compression ratios
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Dorph, E., Wik, L., Strømme, T.A., Eriksen, M., Steen, P.A., and Strømme, T A
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CARDIOPULMONARY resuscitation , *GUIDELINES , *THERAPEUTICS , *HEART diseases - Abstract
Current adult basic cardiopulmonary resuscitation (CPR) guidelines recommend a 2:15 ventilation:compression ratio, while the optimal ratio is unknown. This study was designed to compare arterial and mixed venous blood gas changes and cerebral circulation and oxygen delivery with ventilation:compression ratios of 2:15, 2:50 and 5:50 in a model of basic CPR. Ventricular fibrillation (VF) was induced in 12 anaesthetised pigs, and satisfactory recordings were obtained from 9 of them. A non-intervention interval of 3 min was followed by CPR with pauses in compressions for ventilation with 17% oxygen and 4% carbon dioxide in a randomised, cross-over design with each method being used for 5 min. Pulmonary gas exchange was clearly superior with a ventilation:compression ratio of 2:15. While the arterial oxygen saturation stayed above 80% throughout CPR for 2:15, it dropped below 40% during part of the ventilation:compression cycle for both the other two ratios. On the other hand, the ratio 2:50 produced 30% more chest compressions per minute than either of the two other methods. This resulted in a mean carotid flow that was significantly higher with the ratio of 2:50 than with 5:50 while 2:15 was not significantly different from either. The mean cerebrocortical microcirculation was approximately 37% of pre-VF levels during compression cycles alone with no significant differences between the methods. The oxygen delivery to the brain was higher for the ratio of 2:15 than for either 5:50 or 2:50. In parallel the central venous oxygenation, which gives some indication of tissue oxygenation, was higher for the ratio of 2:15 than for both 5:50 and 2:50. As the compressions were done with a mechanical device with only 2–3 s pauses per ventilation, the data cannot be extrapolated to laypersons who have great variations in quality of CPR. However, it might seem reasonable to suggest that basic CPR by professionals should continue with ratio of 2:15 at present if it can be shown that similar brief pauses for ventilation can be achieved in clinical practice. [Copyright &y& Elsevier]
- Published
- 2003
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44. A randomized controlled trial of chest compression only CPR for older adults—a pilot study
- Author
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Swor, Robert, Compton, Scott, Vining, Fern, Farr, Lynn Ososky, Kokko, Sue, Pascual, Rebecca, Jackson, Raymond E., and Ososky Farr, Lynn
- Subjects
- *
CARDIOPULMONARY resuscitation , *CARDIAC arrest , *HEART diseases - Abstract
Older people are trained infrequently in cardiopulmonary resuscitation (CPR), yet are more likely to witness a cardiac arrest. Older people who are CPR trained perform CPR when witnessing a cardiac arrest. Objective: To assess whether elderly adults (>55 years) who receive chest-compression only cardiopulmonary resuscitation (CC-CPR) training display equivalent skill retention rates compared with those who receive traditional CPR instruction. We also identified factors associated with 3 months skill retention at 3 months in both groups. Methods: Older adults in a suburban hospital Older Adult Services program were invited to participate in an experimental CPR course. The 2 h course was modelled after the AHA Friends and Family course, and used one of two standardized video scenarios. Seventy four subjects were randomized to CC-CPR (n=36) or traditional CPR (n=38) training. Participation consisted of initial training, followed by a 3 months return videotaped assessment. Three months skill competence was assessed either by consensus between two video evaluators, or the on-site evaluator. Chi square and Kappa tests were used for analysis, and unadjusted odds ratios and 95% confidence intervals are reported. Results: Skill retention assessments were completed on 29 (81%) CC-CPR and 26 (68%) CPR trainees. Subjects were elderly (71.5±6.69 years), and had a high rate of previous CPR training (58.0%). Groups were similar in demographic characteristics. After training, participants exhibited high rates of perceived competence (86.4%), although the overall 3 months skill retention was low (43.6%). CC-CPR training resulted in equivalent skill retention rates as compared with traditional CPR training (51.7 vs. 44.4%; P=0.586). No participant factors were associated with skill retention, including age, previous CPR training, education level, medical history, or perceived physical ability to perform. Conclusion: We identified low rates of CPR skill retention in this elderly population. CC-CPR instruction was associated with equivalent skill retention rates compared with traditional CPR instruction. No demographic factors were associated with successful skill retention. [Copyright &y& Elsevier]
- Published
- 2003
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45. Revisiting the cardiac versus thoracic pump mechanism during cardiopulmonary resuscitation
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Haas, Thorsten, Voelckel, Wolfgang G., Wenzel, Volker, Antretter, Herwig, Dessl, Andreas, and Lindner, Karl H.
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BLOOD flow , *CARDIAC resuscitation , *RESUSCITATION - Abstract
The mechanism of forward blood flow due to external chest compressions during cardiopulmonary resuscitation (CPR) remains controversial, with the main theories being based on either a cardiac, or thoracic pump mechanism. Both potential mechanisms are well investigated by echocardiographic assessment. In the present case, a postoperative complication of cardiac tamponade that was detected by a thoracoabdominal CT-scan, led to cardiac arrest with subsequent successful CPR over 15 min until definitive surgical management was performed. This observation suggests that the thoracic pump mechanism may have been the predominant mechanism of forward blood flow in the present case of a pericardial tamponade. [Copyright &y& Elsevier]
- Published
- 2003
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46. Buffer administration during CPR promotes cerebral reperfusion after return of spontaneous circulation and mitigates post-resuscitation cerebral acidosis
- Author
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Liu, Xiaoli, Nozari, Ala, Rubertsson, Sten, and Wiklund, Lars
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ACIDOSIS , *CARDIOPULMONARY resuscitation , *SODIUM bicarbonate - Abstract
To explore the effects of alkaline buffers on cerebral perfusion and cerebral acidosis during and after cardiopulmonary resuscitation (CPR), 45 anaesthetized piglets were studied. The animals were subjected to 5 min non-interventional circulatory arrest followed by 7 min closed chest CPR and received either 1 mmol/kg of sodium bicarbonate, 1 mmol/kg of tris buffer mixture, or the same volume of saline (n=15 in all groups), adrenaline (epinephrine) boluses and finally external defibrillatory shocks. Systemic haemodynamic variables, cerebral cortical blood flow, arterial, mixed venous, and internal jugular bulb blood acid–base status and blood gases as well as cerebral tissue pH and PCO2 were monitored. Cerebral tissue acidosis was recorded much earlier than arterial acidaemia. After restoration of spontaneous circulation, during and after temporary arterial hypotension, pH in internal jugular bulb blood and in cerebral tissue as well as cerebral cortical blood flow was lower after saline than in animals receiving alkaline buffer. Buffer administration during CPR promoted cerebral cortical reperfusion and mitigated subsequent post-resuscitation cerebral acidosis during lower blood pressure and flow in the reperfusion phase. The arterial alkalosis often noticed during CPR after the administration of alkaline buffers was caused by low systemic blood flow, which also results in poor outcome. [Copyright &y& Elsevier]
- Published
- 2002
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47. Combination drug therapy with vasopressin, adrenaline (epinephrine) and nitroglycerin improves vital organ blood flow in a porcine model of ventricular fibrillation
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Lurie, Keith G., Voelckel, Wolfgang G., Iskos, Demos N., McKnite, Scott H., Zielinski, Todd M., Sugiyama, Atsushi, Wenzel, Volker, Benditt, David, and Lindner, Karl H.
- Subjects
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COMBINATION drug therapy , *CARDIAC arrest , *THERAPEUTICS , *ADRENALINE , *VASOPRESSIN - Abstract
There is increasing evidence that the combination of epinephrine (adrenaline) with vasopressin may be superior to either epinephrine or vasopressin alone for treatment of cardiac arrest. However, the optimal combination, and dosage of cardiovascular drugs to minimize side effects, and to improve outcome has yet to be found. We therefore evaluated whether the combination of vasopressin plus epinephrine plus nitroglycerin (EVN), would improve vital organ blood flow during cardiopulmonary resuscitation (CPR) when compared with epinephrine (EPI) alone. After 4 min of ventricular fibrillation (VF) and 4 min of standard CPR, pigs were randomized to the combination of epinephrine (45 μg/kg) plus vasopressin (0.4 U/kg) plus nitroglycerin (7.5 μg/kg; n=12), or epinephrine (40 μg/kg; n=12) alone. Cerebral and myocardial blood flow was measured with radiolabeled microspheres. Defibrillation was attempted after 19 min of VF including 15 min of CPR. Mean±SEM coronary perfusion pressures were significantly (P<0.01) higher 5 min after EVN vs. EPI alone (34±3 vs. 24±3 mmHg, respectively). At the same time, mean±SEM left ventricular, and global cerebral blood flow was also significantly (P<0.05) higher after EVN vs. EPI alone (0.78±0.11 vs. 0.48±0.08 ml/min/g; and 0.37±0.05 vs. 0.22±0.0 3 ml/min/g, respectively). Spontaneous circulation was restored in 11 of 12 animals in the EVN group vs. 6 of 12 swine after EPI alone (P=N.S.). In conclusion, the combination of EVN significantly improved vital organ blood flow during CPR compared with EPI alone. Addition of nitroglycerin to the combination of low dose epinephrine with vasopressin during cardiac arrest may be beneficial. [Copyright &y& Elsevier]
- Published
- 2002
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48. Observation of the magnetic criticality and the magnetocaloric effect in LaMn2Si2 in the vicinity of the phase transition around the room temperature.
- Author
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Bhowmik, Tushar Kanti
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MAGNETOCALORIC effects , *PHASE transitions , *TRANSITION temperature , *MONTE Carlo method , *CRITICAL temperature , *MAGNETIC properties - Abstract
• The magnetic properties of LaMn 2 Si 2 have been studied using the Monte-Carlo simulation. • The ferromagnetic transition temperature (T C) is 311 K, which agrees with the experimental value (310 K). • The RCP value is 82 J/kg for LaMn 2 Si 2 , indicating good magneto-caloric materials. • The T C of the Cu doped LaMn 2 Si 2 (LaMn 1.8 Cu 0.2 Si 2) has gone down to 281 K with the 78 J/kg RCP value. • The critical constants (α = 0.302 , β = 0.328 , γ = 1.293) are nearly same as the 3D-Ising model. In search of the ideal candidate for the room temperature magnetic refrigerator, we found that this ternary intermetallic LaMn 2 Si 2 is very useful for this purpose. So, the detailed magnetic properties and the critical behaviour around the phase transition have been studied through the Monte Carlo simulation process. The critical temperature of LaMn 2 Si 2 is 311 K, which is the same as the previous experimental study. The temperature-dependent magnetic susceptibility, magnetic specific heat, Binder cumulant and the internal energy have been calculated to confirm the phase transition temperature. The critical exponents are determined through the finite-size scaling method at the critical temperature. The values of α , β and γ are 0.302, 0.328 and 1.293, respectively, similar to the 3D-Ising model. The entropy change and the adiabatic temperature change are determined to study the magnetocaloric effect. The relative cooling power (RCP) is 82 J/kg for 6 Tesla applied fields. We then doped 10% Cu in the Mn site to reduce the critical temperature to 281 K and similarly studied the magnetocaloric effect. The RCP value turns out to be 78 J/kg. However, this compound will be a good candidate for the magnetic refrigerator at room temperature without emitting the greenhouse gas. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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- View/download PDF
49. Structural, magnetic and magnetocaloric effect studies of Nd0.6Sr0.4AxMn1-xO3 (A=Co, Ni, Zn) perovskite manganites.
- Author
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Al-Yahmadi, I.Z., Gismelseed, A.M., Al Ma'Mari, F., Al-Rawas, A.D., Al-Harthi, S.H., Yousif, A.Y., Widatallah, H.M., Elzain, M.E., and Myint, M.T.Z.
- Subjects
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MAGNETOCALORIC effects , *MANGANESE alloys , *MAGNETIC cooling , *MAGNETIC entropy , *TRANSITION metals , *MAGNETIC materials - Abstract
• Nd 0.6 Sr 0.4 A x Mn 1- x O 3 (A= Co, Ni, Zn) manganites has been prepared via sol-gel method. • Morphological, structural, magnetic and magnetocaloric properties are studied as a function of dopants. • Co, Ni and Zn doped Nd 0.6 Sr 0.4 A x Mn 1- x O 3 diminishes Mn4+/Mn3+ ratio. • Co, Ni and Zn substitution causes magnetic disordering leading to the presence of exchange bias effect at low temperature. • A promising magnetic entropy change has obtained for Nd 0.6 Sr 0.4 A 0.1 Mn 0.9 O 3 (A= Co, Ni, Zn) compounds providing a good potential for magnetic cooling. The effect of B-site substitution by other transition elements on the structural, magnetic, and magnetocaloric effect properties of Nd 0.6 Sr 0.4 A x Mn 1- x O 3 (x = 0.1 and x = 0.2, A=Co, Ni, and Zn) nanopowders has been reported in this study. Auto-combustion sol-gel method was used to synthesize all the nanopowder samples. Room temperature X-ray diffraction shows that all the nanopowders have orthorhombic structure of Pnma space group crystallography, confirming the purity of the single phase. Also, the average nanosized scale of these powder samples is ~ 43 nm, revealing a spherical shape with a packed and homogenous structure. The Mn4+/Mn3+ ratio in these nanopowder compounds is highly dependent on the dopants concentration (x), which shows a significant diminishes as the dopants introduce into the parent compound (Nd 0.6 Sr 0.4 MnO 3). The decrease in the Mn4+/Mn3+ ratio enhances in the antiferromagnetic (AFM) super exchange interaction (SE) due to the lack of Mn3+— O—Mn4+ ferromagnetic (FM) double exchange (DE). The magnetization measurements indicate that all samples exhibit a ferromagnetic (FM) to paramagnetic (PM) transition with increasing temperature. The Curie temperature (T C) is also affected by the dopants concentrations where considerable decrease has been noticed for all compounds compared to the parent compound. The M-H curves for all compounds reveal PM behavior at 300 K, whereas FM behavior characterized the magnetic hysteresis at low temperature (2 K) which also shows the presence of exchange bias effect. The magnetic entropy change | − ∆ S M Max | has shown bigger effect for Co dopant (5.92 J/kg.K) compared to Ni and Zn dopants with values of 5.19 J/kg.K, and 4.28 J/kg.K respectively at an applied magnetic field of 9 T. Despite substituting at Mn-site by other transition elements lower the Tc, | − ∆ S M Max | and RCP, the obtained results are promising for magnetic cooling materials and further investigation. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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50. Decadal application of WRF/Chem over the continental U.S.: Simulation design, sensitivity simulations, and climatological model evaluation.
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Wang, Kai, Zhang, Yang, and Yahya, Khairunnisa
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EMISSION inventories , *CLOUD dynamics , *AIR quality , *RADIATIVE forcing , *CLIMATE change , *CUMULUS clouds - Abstract
The WRF/Chem v3.7 is applied to 2001–2010 over the continental U.S. using the National Emission Inventory (NEI). This study will provide the baseline simulation for a future work to investigate the impacts of both climate and emission changes on the future regional air quality and human health. This paper focuses on the current year simulation design, comprehensive model evaluation, and sensitivity simulations that demonstrate the impacts of different reinitialization setup, cloud physical schemes, and emission inventories on the model predictions. Nine one-month sensitivity simulations by using different reinitialization setup and cloud microphysics and cumulus parameterizations are first conducted to provide the optimal model configurations. The model performance in predicting the regional meteorology and air quality on a decadal scale is further evaluated against available surface, satellite, and reanalysis data. The decadal WRF/Chem simulation by using NEI emissions (referred to as simulation NEI) performs well for major meteorological variables such as T2, RH2, WS10, and precipitation and shows good performance for major radiation variables such as SWDOWN, OLR, and SWCF. Large model biases still exist for cloud variables due to limitations of cloud dynamics/thermodynamics treatments and uncertainties associated with satellite retrievals. The simulation NEI also predicts O 3 and PM 2.5 well in terms of spatiotemporal distribution. Compared to a previous study using the Representative Concentration Pathway (RCP8.5) emissions, the simulation NEI performs better for most of variables, especially for precipitation and cloud radiative forcing due to better representation of cloud processes and also for O 3 and PM 2.5 in terms of spatiotemporal variations due to more accurate emission inventory. The evaluation results in this work are within the range or better than other previous studies using the WRF/Chem model and lay the foundation for more realistic projection of future climate and air quality in the future work. • Decadal application and evaluation of online coupled WRF/Chem in the U.S. • Monthly reinitialization and Morrison + MSKF schemes produce better cloud fields. • Good performance for major meteorological and chemical variables compared to literature. • WRF/Chem with NEI emissions outperforms that with RCP emissions. • Model biases may introduce uncertainties on future air quality projections. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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