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The Plum Rains Season (PRS) has the typical characteristics of outdoor air temperature dramatic changes and high air humidity in the hot summer and cold winter region in China. Even if the indoor heat source and moisture production is constant, when the outdoor air temperature rises rapidly during high air humidity PRS, the building envelope temperature heats up much more slower than the indoor air temperature and therefore the wall surface temperature is lower than the indoor air dewpoint which leads to condensation phenomenon, resulting in deterioration of insulation performance, mouldy walls, deterioration of indoor air quality. At present, there is a lack of research on the factors affecting condensation in rural residence during PRS. This paper evaluates the impact of occupants’ habit of window opening modes and building construction parameters on the building envelope surface condensation in Changsha during PRS. Using Designer'Simulation Toolkit (DeST) simulated and analysed the impact of key parameters such as window-to-wall ratio, exterior wall reflectivity, window opening mode (open/close), and external wall insulation on the building indoor thermal and humid environment. The condensation risk X is proposed to evaluate the condensation possibility on the building envelope's inner surface. The results show that from the perspective of anti-condensation: The rural residential building in Changsha should balance the window-wall ratio against better natural lighting; Keeping windows closed during PRS can effectively alleviate the condensation problem while the insulation in the external wall layer could aggravate the condensation.

Використання комбінованих знарядь у системі підготовки ґрунту до сівби дозволяє зменшити енергетичні і трудові витрати на одиницю вирощеної продукції при збереженні родючості ґрунту з максимальним економічним ефектом. При підготовці ґрунту до сівби є важливим створення дрібногрудочкової структури ґрунту з використанням простих машин та знарядь. Мета досліджень – підвищення якості структурного стану ґрунту під час підготовки до сівби з використанням найпростіших і високопродуктивних знарядь і машин, зменшення питомих енергетичних витрат на підготовку ґрунту до сівби сільськогосподарських культур. Застосування комбінації робочих органів для розпушення ґрунту в одній машині дозволяє інтенсифікувати процес кришіння ґрунту і розширити діапазон використання машини чи знаряддя для підготовки ґрунту до сівби сільськогосподарських культур. Одним із шляхів розв’язання проблеми якісної підготовки ґрунту до сівби сільськогосподарських культур є застосування високопродуктивних комбінованих багатоопераційних агрегатів, які за один прохід забезпечують розпушення, вирівнювання поверхні ґрунту та його необхідне ущільнення. Такі агрегати запобігають переущільненню ґрунту, характерному для традиційного обробітку, а завдяки формуванню добре розпушеного поверхневого шару зменшують випаровування вологи. Порівняльний аналіз агротехнічних показників роботи борони-культиватора, виконаний на основі польових випробувань, дав змогу встановити, що підвищення коефіцієнта якості розпушування ґрунту на 14...17%, коефіцієнта якості кришіння на 10...17,6% порівняно із серійними боронами розширює функціональні можливості використання борони-культиватора з експериментальними гнутоштабовими зубами для обробітку ґрунту. Впровадження в практику використання борін з гнутоштабовими зубами уможливлює підвищення якості обробітку ґрунту, збільшення продуктивності праці та скорочення енергетичних затрат.

Pollution resulting from terrestrial and aquatic trace elements has become a severe problem across the world. Organic carbon (OC) content has a high affinity for metallic contaminants and it acts as a significant sink for trace elements. The decomposition of OC content directly influences the bioavailability of trace elements. The decomposition of OC content and OC distribution vary spatially, these processes affect the release of trace elements and need further research. In the current study, sediment samples from the surface sediment along Beiyun River (Section 1 to Section 4 from upper to lower reaches), which is situated in the rapidly urbanized Beijing metropolis, were measured for OC, moisture, hardness, and trace elements. The OC contents were found to have a substantial difference among all four river sections along the urbanized river gradient. Whereas the higher OC contents were found in sections 2 (Urbanized uplands) and 3 (farmland) compared to those in sections 1 (forest) and 4 (farmland and part of constructed areas). On the other hand, the highest value of the correlation coefficient was found among the different values of trace elements and OC content in the riverine zone of the Beiyun River basin. OC contents play a vital role in the transformation and origin of trace elements in the surface sediment of the Beiyun River basin. The One-way Analysis of Variance (ANOVA) was applied to compare the means of OC and trace elements at different sections indicating no significant difference. However, source identification of trace elements indicated that a geogenic source was responsible for higher contents of arsenic (As) and manganese (Mn) (69.95%). Simultaneously, the natural OC, agricultural activities, and industrial waste contributed about (21.10%) towards the cadmium (Cd) and zinc (Zn), and about 10% for chromium (Cr) and copper (Cu). The current study concludes that the absolute principle component analysis-multiple linear regression (APCA-MLR) method can be successfully be used to investigate the trace elements (Zn, nickel [Ni], lead [Pb], Mn, Cd, Cu, and As) interactions through OC content resulting in determination of the various sources of contamination to cause negative environmental impacts on the ecosystem and human health. So, the current study provides a baseline for a quantitative evaluation of trace elements under different sediment of OC contents.

Determination of an appropriate location for monitoring soil water content (SWC) is a key factor in efficient use of water in precision agriculture, however, the main challenge is the dynamic movement of water and root development in the soil profile. The objective of this study was investigating how SWC distribution in a loam soil profile at two growth stages of maize may impact the suitable location for SWC monitoring in a drip-tape irrigation system. A new concept, Average Moisture Representative Surface (AMRS) was proposed to determine the surface of the soil profile, which represent the average soil moisture of the wetted volume. SWC samples were taken during two irrigation intervals (48~52 days after planting (DAP) and 68~73 DAP) and root growth pattern was studied through root length density (RLD) at 50 and 100 DAP. The results revealed that a non-uniform wetting pattern after irrigation limits the appropriate locations for SWC monitoring to point measurements and with time, SWC depletion resulted in enlarging AMRS. At the end of growing season, an increase of root growth around the drippers increased the variation of root water uptake in different soil layers, and thus optimal place for soil sensors was limited to the upper layers, where the maximum root water uptake occurred. Overall, it is recommended to install soil sensors, such as tensiometers and TDRs at a horizontal distance of 5~20 cm from the crop and a depth of 10~20 cm from the soil surface while drip-tape is aligned close to the maize row.

The Great Plains Low-Level Jet system consists of very strong winds in the lower troposphere that transport a huge amount of moisture from the Gulf of Mexico to the American Great Plains. This paper aims to study the extremes of the Transported Moisture (TM) from the GPLLJ source region to the jet domain; and, for low and high TM, to analyze the extremal dependence between the upper tail of the precipitation in the GPLLJ sink region and the lower tail of the tropospheric stability in that region (omega). The declustered extremes of TM were analyzed using Peaks Over Threshold (POT). A non-stationary Exponential model was fitted to the cluster maxima. Estimated return levels show that the extremes of TM are expected to decrease in the future. This is meteorologically congruent with the known displacement of the western edge of the North Atlantic Subtropical High, which controls atmospheric circulation in the North Atlantic, and to a higher scale with the change of phase from negative to positive of the Atlantic Multidecadal Oscillation. Bilogistic and Logistic models were fitted to the extremes of (-omega, precipitation) for low and high TM, respectively. The extremal dependence between "-omega" and precipitation proves to be stronger in the case of high TM. This confirms that dynamical instability represented by “-omega” is the most important parameter for achieving high values of precipitation once there is a mechanism that allows the continuous supply of large amounts of moisture, such as the derived from a low-level jet system.

Propagation of grasses through seeds is important in view of vigour and germination. Various grasses as Pennisetum pedicellatum Trin., Cenchrus ciliaris L., Chrysopogan fulvus have lower vigour and germination, due to which they need specific operations as defluffing, separation of true seeds, cleaning and grading by specific machines. In designing a machine for a specific use, physical properties and their behaviour with moisture play an important role. A study was conducted to assess the effect of moisture content at five levels [6.88 - 19.23 %, (d.b.)] on selected physical properties of defluffed Deenanath grass seed. The length, width, thickness, arithmetic mean diameter, and geometric mean diameter of defluffed Deenanath seed increased from 2.30 mm to 2.56 mm, 0.71 mm to 0.96 mm, 0.47 mm to 0.63 mm, 1.16 mm to 1.38 mm, and 0.90 mm to 1.15 mm, respectively, with increase in moisture content 6.88 % to 19.23 %. Bulk density, true density, and porosity decreased from 652.16 kg.m-3 to 585.78 kg.m-3, 852.63 kg.m-3 to 792.71 kg.m-3, and 25.62 % to 24.97 %, respectively, with increase in moisture content from 6.88 % to 19.23 per cent. The aspect ratio, sphericity, surface area, volume, and thousand-seed mass of the seed were in the range of 30.91 - 37.51 %, 0.39 - 0.45, 2.58 - 3.23 mm2, 3.71 - 4.97 mm3, and 0.480 - 0.523 g, respectively. Linear relationships with correlation coefficients higher than 0.90 were observed for the physical properties over the experimental range of moisture content.

Soil moisture level is crucial to soil phosphorus (P) availability; however, there is no quantitative research on the relation between soil P availability and moisture level. In addition, biochar application could also alter soil P availability at different moisture levels. In this study, a 16 d soil incubation experiment was conducted at a laboratory scale to analyze the effects of soil moisture and P fertilization regimes (P-laden biochar fertilizer and conventional mineral P fertilizer) on soil P availability and fractionation. The results showed that soil P availability was positively correlated with soil moisture level (Pearson coefficients ranged from 0.46 to 0.91). High moisture level would lead to less amount of P in readily available fractions under P-laden biochar application. However, even with less P in readily available fractions, P-laden biochar could maintain soil P availability (117.7 mg P·m−2) at a similar level as the conventional P fertilizer (116.1 mg P·m−2).

The Amazon Basin is dominated by convective rainfall with significant spatial and diurnal variability. Diurnal and seasonal distributions of convective events were determined from rainfall and Cloud Top Temperature (CTT) between January 2008 and December 2010 in city Belém-PA. The decis technique was used to select the most intense events (rainfall rate ≥ 15 mm h–1), which were subsequently, subclassified into deep convection events (DCE) and shallow convection events (SCE). Ninety four cases were found, mostly occurring between 12 and 19 LT, and 55% in the rainy season. Another set of DCE and SCE with rainfall rate ≥ 1 mm h–1 was selected to analyze the effect of seasonality. Of these, 42 cases were found also between 12 and 19 LT, with a maximum at 16 LT. Temperature profiles differed between the rainy and less rainy seasons, in the intensification of shallow and deep convection. Moisture profiles showed greater variability between 850 and 500 hPa, indicative of their role in convective activity; during the rainy season the atmosphere was more humid (less humid) before (at the time) of the occurrence of DCE. Wind components showed significant shear between surface and ~850 hPa, with stronger zonal component in the cases of DCE. The highest values of CAPE were observed about 2 to 3 hours before DCE and SCE, with maximum values before DCE in the rainy season. Results presented here are relevant to improve short-term forecasts and convective event simulations with numerical weather and climate models.

Several studies have shown that the competition for fresh water is increasing, and there is a need to sustainably manage the available water for crop production. Also, studies that investigate the use of fish wastewater to irrigate sweet pepper are scarce. Therefore, a field experiment was carried out to investigate and compare the growth yield, and nutrient composition of sweet pepper under fish wastewater and borehole water. Experimental design consisted of a Randomized Complete Block Design (RCBD). The treatments include; 50% Potential Evapotranspiration (PET) with fish pond water (T1), 100% PET with fish pond water (T2), and 100% PET with borehole water- control (ground water), (T0) and were replicated three times. Soil physico-chemical properties, Pepper Agronomic parameters (growth and yield) and nutrient compositions (moisture, fat, ash, protein, carbohydrate and crude fiber) were determined using standard procedures. Results showed that the water quality of fish wastewater (aquaculture) and ground water used for irrigating pepper was within the permissible limits when compared to standard. Also, Aquaculture water improves the soil physico-chemical and soil water content, which consequently led to improved growth and yield of pepper. The average plant height values were 59.00 cm, 37.50 cm, and 45.00 cm in treatments T2, T1 and T0, respectively. Similarly, the highest number of leaves, stem girth, biomass and sweet pepper yield, root weight and Leave area index (LAI) were recorded in treatment, T2. In addition, highest nutrient compositions were recorded in treatment T2, while the least was recorded in treatment T0. Statistical analysis showed that agronomic and mineral composition parameters were significantly different (P

Volumetric changes in expansive soils due to seasonal moisture changes can seriously damage foundations. In the small-scale laboratory study reported in this paper, the effect of inserting columns made from calcium carbide residue (CCR) and fly ash (FA) to reduce the swelling potential of expansive soil was examined. An attempt was made to determine the mineralogical changes in the soil and to identify newly generated reaction products by X-ray diffraction (XRD). The strength gain of the stabilised soil was investigated using unconfined compressive strength tests. It was found that the heave of the soil with columns of CCR and FA installed by in situ mixing and compaction reduced by up to 88% and 57%, respectively. The compressive strength of samples increased up to two-fold, and around the same level, for both installation methods after 90 d of curing. This increase in strength was an outcome of soil modification and stabilisation. The XRD results indicated the change in soil mineralogy. Further studies are required to study the cyclic swell–shrink behaviour of the stabilised expansive soil.

In high-temperature and high-humidity environments, a large amount of energy is consumed to cool and dehumidify outdoor air by dedicated outdoor air systems in nearly zero energy buildings. Desiccant wheels have the advantages of large moisture removal capacities and continuous regeneration. However, the application of desiccant wheels in nearly zero energy buildings is limited by their large regeneration heat capacity and high temperature after dehumidification. A dedicated desiccant wheel outdoor air cooling system is thus proposed. An experimental setup is built and used to test the performances of three modes for dedicated desiccant wheel outdoor air cooling systems. The results show that mode Ⅰ (wet membrane humidifier downstream evaporation section of heat pipe heat exchanger) has a higher performance coefficient and higher exergy efficiency compared to other modes. The thermodynamic and exergy performances of the proposed mode Ⅰ system are determined. The results show that the thermodynamic coefficient decreases from 1.3 to 0.52 and the exergy efficiency decreases from 0.76 to 0.18 when the regeneration temperature increases from 60°C to 110°C.

The first rainy season (April–June) of South China includes the phases before and after the onset of the South China Sea summer monsoon (SCSSM). Abundant moisture supply is the key dynamic process for precipitation formation. Thus, we employ the FLEXPART model to explore the corresponding moisture sources for the two phases. Before the onset of SCSSM, land regions contribute more moisture to the precipitation over South China than the ocean sources. The main source regions are Southeast Asia (27.01%), the South China Sea (25.96%), South China (11.12%), and the southern part of the northwestern Pacific (10.23%). Land sources (66.87%) play a more important role than ocean sources (33.13%) in the interannual variations, with the contributions mainly from Southeast Asia (47.56%) and the South China Sea (28.79%). After the onset of SCSSM, the climatological contribution of ocean sources is larger than that of land regions, and the main source regions are the South China Sea (20.78%), Southeast Asia (17.51%), the Bay of Bengal (13.76%), and South China (11.21%). For the interannual variations, the contributions of land sources and ocean regions are comparable, and mainly from Southeast Asia (33.53%) and the Bay of Bengal (32.26%). The moisture transports for the interannual variations in first rainy season precipitation over South China before and after the onset of SCSSM are significantly correlated with the east–west contrast of sea surface temperature anomalies over northern part of North Pacific and the uniform warming over Indian Ocean, respectively. This study provides important guidance in improving the regional precipitation predictions and understanding the water resources changes.

Technological developments in the era of Globalization, are widely used in various fields, one of the developing technologies is the technology on the NodeMcu ESP8266. In the Soil moisture Detector System in Ornamental Plants Using the IoT-Based NodeMcu ESP8266, based on the problem factors that exist in a failure in plant growth, it is very influential in terms of technique and also improper plant watering procedures, can cause plant growth to be disrupted and also withered. To overcome this problem, the author designed a Moisture Condition Detector in Ornamental Plants Using an IoT-Based NodeMcu ESP8266. Where this system can run commands to automatically water plants from soil moisture while simultaneously watering manually with various desired conditions and the system can send notifications that users can receive via telegram. Through the Moisture Level Condition Detector system in this ornamental plant, it can increase the level of effectiveness, so the quality that the plants get will be better maintained.

Typical fire extinguishing agents were considered: water; bischofite solutions (with a mass fraction of 5% and 10%); bentonite slurries (with a mass fraction of 5% and 10%); foaming agent emulsions (with a mass fraction of 5% and 10%). The heating temperature range of 150-400°С was chosen to correspond to the conditions of rapid thermal decomposition of forest fuels. The experimental research findings suggest that the rates of moisture release depend exponentially on the heating temperature. It was established that the rates of moisture release in the above temperature range may differ significantly for the forest fuels and fire extinguishing agents under study. Conditions were identified when the general approximation equations, presented in this paper, can be used to predict the vaporization characteristics of firefighting liquids.

The short and scare record limits to understand the history of the hydroclimate change in east-central China. In this study, we developed a 225-year tree-ring width chronology (STD) for Chinese pine originating from the Shiren Mountain in Henan Province, east-central China. We analysed the correlation between the STD and different climatic factors and then reconstructed the May–June moisture variation, which is one of the longest moisture variation reconstruction based on tree-ring width in this region. Further, the results of the spatial analysis between our reconstruction and actual moisture variation revealed that our reconstruction is representative of large-scale May–June self-calibrating Palmer Drought Severity Index (scPDSI) in east-central China. Additionally, the reconstruction showed five relatively dry and five relatively wet epochs over the past 225 years. It also showed that the moisture variation in the study area is similar to those corresponding to other nearby sites and could be validated by historical documents; these findings demonstrate the reliability of our reconstruction back in time. Furthermore, we detected the reason for the coherent May–June moisture change in east-central China. It showed that the actual scPDSI showed significantly positive correlations with concurrent precipitation. Additionally, regression analyses showed that precipitation is largely determined by the frontal system, which is also responsible for the coherent May–June moisture pattern observed in east-central China. In addition, the result of spectral analysis and correlation patterns of the reconstructed scPDSI with global sea surface temperatures indicated that the El Nino-Southern Oscillations might be the forcing mechanism for regional moisture variability.

The novel hybrid greenhouse solar dryer (HGSD) attached with evacuated tube collector (ETC) is developed for faster drying of high moisture content crops. The slow drying rate of high moisture crops lead to microbial attack on crop surface and have more chance of deterioration. Hence the HGSD is designed and tested for faster drying of crops. The experiments are performed to evaluate the performance of HGSD under active and passive mode. Ginger has been taken as a high moisture crops for the experimentation on two cases. In both the cases the ginger is dried from 79.8% to 9.82% moisture level (wb). In active mode, dryer takes 43.47% less time than the passive mode. The overall efficiency of the dryer in active and passive mode is 4.81% and 3.39% respectively. The lower drying time makes this dryer suitable for rural as well as commercial applications for drying agricultural or non-agro based products.

Disposal of increased waste material is always a major problem in construction industry because of heavy weight and occupies more storage space. In this research study, various combinations of C&D waste and GGBS is used as stabilized material and polypropylene fiber as reinforced material to improve the geotechnical properties of Black Cotton soil. The purpose of this research is to analyze the result of various combination of C&D waste, GGBS and PPF on the geotechnical properties of the earth soil. Soil improvement is one of the major tasks on which maximum number of experiments need to be performed in depth. So, experimental studies showcased that optimum utilization of C&D waste, GGBS and PPF can effectively help in reducing swelling, shrinkage property of BC soil. As PP fiber does not absorb moisture it has excellent chemical resistance to most acids and alkalis.

Indian jujube (Ziziphus mauritiana) and Date palm (Phoenix dactylifera L.) the most important fruit crops that can grow in India's hot arid regions. The perishable nature of Indian jujube and date fruits leads to post-harvest loss. Both of these fruits are highly perishable, containing more than 80% moisture. Moisture needs to be reduced to less than 20% for storing it for a longer period of time. A phase change material (PCM) based hybrid solar dryer was developed, which consisted of the collector of area 1.06 m2 and two drying trays made of SS (0.50 m2) and that two half trays (0.24 m2). The performance of the developed PCM dryer was evaluated by drying fresh Indian jujube and date palm fruits having an initial moisture content of 65–80% (wet basis) and compared with the developed dryer without PCM. The drying system works so that phase-change material stores the thermal energy during sunshine hours and releases it at night. Therefore, the dryer is effectively operative for the next 5–6 h. The temperature of the drying chamber was observed as 6 °C higher than the ambient temperature in July 2020 during date palm drying after sunshine hours till midnight and it falls gradually, and temperature in the drying chamber was observed as 5°Celsius higher than the ambient temperature in January 2021 during Indian jujube drying. The variations in moisture content (wet basis) of the Indian jujube fruit are reduced from 80% to 22% within seven days by using the dryer with PCM and in 9 days dryer without PCM. In date palm fruit, MC reduced from 65 to 20% in 6 days in the dryer with PCM and eight days without PCM. The thermal efficiency (η) of PCM based hybrid photovoltaic thermal (PV/T) solar dryer (η = 18.0%) was found better than that of natural convection mode without PCM based hybrid solar dryer (η = 15.8%). The developed solar dryer provides a promising alternative for drying other arid food produced after sunshine hours with a real-time data acquisition system. It is also found to be superior in retaining quality.

Long-term continuous monitoring of precipitation isotopes has great potential to advance our understanding of hydrometeorological processes that determine stable isotope variability in the monsoon regions. This study presents 4-yr daily precipitation isotopes from Yungui Plateau in southwestern China that are influenced by Indian summer monsoon and East Asian monsoon. The local meteoric water line (LMWL;δ2H = 8.12δ18O + 11.2) was first established at the Tengchong (TC) site, which was close to the global meteoric water line (GMWL;δ2H = 8δ18O + 10), indicating little secondary subcloud evaporation in the falling rain. Precipitationδ18O values exhibited significant inverse relationships with precipitation amount (r= −0.42), air temperature (r= −0.43), and relative humidity (r= −0.41) with lower correlation coefficients throughout the entire period, which indicated that precipitation isotopic variability in TC could not be well explained by the local meteorological factors but influenced by other combined factors of regional precipitation amount and upstream rainout. Precipitationδ18O values showed a clear V-shaped trend throughout the observation period, characterized by higherδ18O values during the premonsoon period whereas lower values during the postmonsoon period. This seasonal variation of precipitationδ18O values was associated with the seasonal movement of the intertropical convergence zone and seasonal changes in moisture transport. Combined with backward trajectory analysis, precipitationδ18O values were estimated by a Rayleigh distillation model showing that upstream rainout processes from the Bay of Bengal (BoB) toward land (Myanmar) and recycling moisture over land were key factors affecting the isotopic compositions of the TC precipitation. These findings could enhance our understanding of atmospheric dynamics and moisture source in the monsoon regions and will potentially facilitate the interpretation of numerous isotopic proxy records from this region.SIGNIFICANCE STATEMENTThe variability of the summer monsoon and its onset, duration, and failure directly determine the strong rainfall and drought in a given region and have great impacts on regional societies and agriculture. To better understand this variability, this study presented a 4-yr daily dataset of precipitation isotopes on the Yungui Plateau of southwestern China to explore atmospheric processes and moisture sources that drive isotopic variability in this region. Precipitationδ18O exhibited remarkably seasonal variability, with higher values in premonsoon period and lower values in the postmonsoon period. During the Indian summer monsoon period, moisture sources primarily originated from the BoB toward the TC site, experiencing rainout processes and local moisture recycling over land using a Rayleigh fractionation model. These findings shed new light on the temporal variations of precipitation stable isotopes and facilitate our understanding of hydrological cycle in the monsoon regions.

Coal bed methane (CBM) extraction keeps on going through innovative work. Concerns incorporate evaluating the asset, distinguishing good geologic creation zones, setting up effective recuperation plans, exhibiting progressed penetrating advancements and supporting catch and utilization of less available gas streams. Coal of Raniganj field has a unique characteristic incorporating the best non-coking coalfield in India. Proximate analysis indicate that the ash content is less than 20% and the content of volatile matter, fixed carbon and moisture are in the desired range. X-ray diffraction (XRD) examination demonstrates the presence of 48.1% C4H6O6 that is of monoclinic crystal framework and continuous expansion in diffraction band from 198 to 98 at 2θ = 17.62 and 20.0001 Angstrom representing a better coal seam and presence of aliphatic compounds. FT-IR study reveals the presence of aliphatic hydrocarbons associated with CH2 stretching at 2100.05 cm−1, aromatic C=C (1637.92 cm−1) band associated with –OH(3439.95 cm−1) stretching vibrations.

The performance investigation of natural and forced convection indirect type solar dryers was performed by drying ivy gourd. The natural convection setup was modified by fitting a trapezoidal duct and central processing unit fans run by photovoltaic panels to promote forced convection. The data from the experiment was used to estimate collector and dryer efficiencies, energies, effective moisture diffusivity, transfer coefficients, specific energy consumption and specific moisture extraction rate. The average actual heat supplied was 776.6 and 997.76 W for natural and forced convections, respectively. The average collector efficiency for the same was 62.56% and 77.2%, respectively. The average drying efficiency for the same was 6.62% and 7.8%, respectively. The average values of activation energy, mass transfer, heat transfer and diffusion coefficients were estimated to be 39.85 and 35.54 kJ/mol, 7.06 × 10−9 and 8.35 × 10−9 m2/s, 0.0033 and 0.0043 m/s, and 3.85 and 4.93 W/m2 K, respectively, for natural and forced convection setups, respectively. The specific energy consumption and specific moisture extraction rate were evaluated where forced convection setup gave the best results. The drying correlations were developed for mass transfer, heat transfer and diffusion coefficients. Uncertainty analysis was performed to check the authenticity of the results.

Greenhouse drying systems are sustainable and clean applications for preserving agricultural crops. In this work, a single-slope greenhouse drying system has been modified with solar absorber and thermally insulated north wall. Also, the designed and manufactured north wall has been coated with graphene nanoplatelet-embedded black paint. Greenhouse dryers with north wall and nano-embedded north wall modifications have been experimentally compared with a conventional greenhouse dryer. Main goal of this research is to upgrade the performance of a greenhouse drying system without using any auxiliary heating device and complex structural components. According to the experimental outcomes, drying time was reduced as 75 and 90 min by utilizing north wall and nano-enhanced north wall, respectively. Furthermore, exergy efficiencies of greenhouse dryers with north wall and nano-enhanced north wall were attained as 4.67% and 5.38%, respectively while this value for conventional greenhouse dryer obtained between 2.61 and 2.70%. Moreover, utilizing graphene nanoplatelets in black paint improved the specific moisture extraction rate as 40% in comparison to conventional greenhouse dryer.

HighlightsUneven drying is an inevitable drawback when using heat pump-based deep-bed dryers in commercial drying industries.Understanding the drying behavior of the heat pump-based deep-bed dryers is important to optimize the drying technology.COMSOL Multiphysics is a very helpful tool as it can be used to predict the drying behavior.Abstract. Heat pump dryers are widely used in drying agricultural products because of its capability in drying products at comparatively lower temperatures in commercial scale. However, deep-bed heat pump drying (HPD) leads to uneven drying because of its poor airflow distribution in the drying chamber. Optimizing the proper design of a heat pump dryer system may reduce the non-uniformity of drying and increases dryer efficiency. This study aimed to investigate the airflow distribution in a deep bed of rough rice dried with a heat pump using Computational Fluid Dynamics (CFD). The Navier-Stokes equation, Heat transfer equation, and Fick’s Law were used in the mathematical models for simulation of air velocity, temperature, and relative humidity respectively. COMSOL Multiphysics simulation program v5.4 solved all the models with the boundary conditions of inlet velocity, inlet temperature, and drying air moisture content. The simulation was used to predict the temperature and the humidity of drying air at three different dryer locations during the drying process. Finally, the simulated data were verified using experimental results. The values of relative error and mean relative deviation for drying air temperature in paddy bed were less than ±18.05%, 13.52%. Relative error and mean relative error for air moisture in paddy bed were less than ±15.83% and 14.44%, respectively. The results indicated that the simulation model developed could effectively use for predicting the air temperature and air relative humidity with a reasonable accuracy. Keywords: CFD simulation, COMSOL Multiphysics, Heat pump drying.

HighlightsDesign characteristics for animal mortality compost cover materials were tested.Compressive stress was applied to simulate the effects of the mortalities on cover materials.The highest permeability was measured for sawdust at 25% moisture content.A linear relationship was found between the volumetric flow rate and the power required to aerate the piles.Abstract. Composting is an aerobic process that relies on natural aeration to maintain proper oxygen levels. Air-filled porosity, mechanical strength, and permeability are among the essential parameters used to optimize the process. This study’s objective was to measure the physical parameters and airflow characteristics of three commonly used cover materials at four moisture levels, which could be used in designing actively aerated swine mortality composting systems. A laboratory-scale experiment was conducted to measure pressure drops across the cover materials as a function of the airflow rate and the material’s moisture content. Compressive stress was applied for 48 h to simulate the impact of swine mortalities on the cover materials. The power required to aerate each material was determined as a function of volumetric flow rate and moisture content. As expected, air-filled porosity and permeability decreased with increasing bulk density and moisture content. The highest average permeability values were measured at 25% moisture content and ranged from 66 × 10-4 to 70 × 10-4 mm2, from 161 × 10-4 to 209 × 10-4 mm2, and from 481 × 10-4 to 586 × 10-4 mm2 for woodchips, ground cornstalks, and sawdust, respectively. For the range of airflow rates tested in this study (0.0025 to 0.0050 m3 s-1 m-2), a linear relationship (R2 = 0.975) was found between the volumetric flow rate (m3 s-1) and the power required to aerate the compost pile (W per 100 kg of swine mortality). Keywords: Airflow, Darcy’s law, Livestock, Modeling, Permeability, Pressure drop.

Global efforts to feed the burgeoning population have focused on increasing food production and access. In the meantime, FAO estimates about 1/3 food loss in the developing countries. To minimize these losses, grain storage techniques were investigated in an earthquake hit village in Kavre district of Nepal. Pesticide free moisture proof/airtight food storage bags were provided to 1,055 households using financial support from UNICEF-Nepal. Thirty-three households were identified who could store food grains for 6-month for this study. Maize and rice grains were stored in porous and in moisture-proof hermetic bags. Food grain samples were collected at the beginning and at 6-month and were analyzed for physical quality parameters, nutrients and mycotoxins. About 92% insect damage occurred in maize stored in porous bags which was prevented in triple layer hermetic Purdue Improved Cowpea Storage (PICS) bags. Insect damage in paddy remained low within 10% in both treatments. Major maize nutrient loss occurred through insect damage. The traditional practice was to use insect and mold infested maize as feed. Mycotoxins results showed that toxigenic molds develop in open storage of improperly dried grains especially maize. Fusarium-related mycotoxins associated with stunting were detected in maize samples using LC-MS/MS equipment. Mature grains should be dried sooner to processing moisture contents and packaged into moisture-proof hermetic bags (Dry Chain) to minimize postharvest loss. A clear policy implication is that use of improved low-cost Dry Chain technology should be promoted to enable quality food systems.

Relevance. The experience of constructed cellular structures and the results of computational and model studies carried out in our country and abroad to assess the joint work of the complicated complex cellular frame - soil backfill of cells - foundation indicates the sufficient reliability of such hydraulic structures. The main difficulty in the design of cellular structures is to reproduce the volumetric work of the complex cellular frame - backfill soil - foundation soil to identify structural reserves. Objectives. To study, through laboratory studies, the interaction of the frame and backfill of the cell and the base at different soil moisture, taking into account such factors as the granulometric composition of the backfill soil, the role of the surface tension of moisture contained in the soil, the geometric parameters of the structure itself and a number of other factors. Methods. Experimental studies on the model of the operation of a cellular structure without a bottom on a non-rocky (sandy) foundation for stability, subject to the similarity criteria, as well as studies of cells with different geometry and sizes with changes in moisture and particle size distribution of the soil of the cells. Results. Based on the results of model studies, a dependence is proposed to take into account the effect of surface tension forces, considering the hydraulic radius of the cell cross-section, wetted perimeter, cross-sectional area of the cell, etc. The interaction of the cellular structure with the base is also explored, taking into account the above parameters. The results of laboratory studies on considering the interaction of the frame and backfill of the cell soil at different moisture content of the aggregate, taking into account the granulometric composition of the backfill soil surface tension of moisture contained in the soil, geometric parameters of the structure itself and a number of other factors.

In permafrost peatlands, the degradation of permafrost soil can raise soil temperature and alter moisture conditions, which increases the rate of loss of soil organic carbon (SOC). Here we selected three typical permafrost types that have very different active layer thicknesses but with soil originating from the same vegetation and which exist under comparable climatic conditions in the Da Xing’an mountain range: continuous permafrost, island permafrost, and island melting permafrost. To quantify the relative importance of control elements on SOC stabilization in these different permafrost types, we used correlation analysis to assess the relationship between organic carbon, physical and chemical properties and microorganisms, and explored the contribution of these factors to the accumulation of organic carbon. This study shows that the interaction between clay or silt, iron oxides and microorganisms have an important influence on the stability of organic carbon in permafrost peatlands.

Sand production is considered as one of the significant production issues that significantly reduce wellbore productivity. The process of sand or solids production in production operations is one of the crucial operational inefficiencies that can lead to wells collapsing. Besides, the drilling mud might erupt through the formation. Therefore, it is essential to properly determine what types of solids or sand are produced to correctly predict efficient sand control mechanisms. This paper aimed to compare different sand production control mechanisms and how to control or minimize sand production. Moreover, we consider injection pressure and sand moisture on the sand production rate. According to this study’s findings, pressure injection and moisture increase had caused sand production increase, which should be considered in operational performances. Furthermore, chemical injection such as resin and hydrogel injection usually has efficient sand production control methods. An expandable sand screen is an expandable three-layer component that is driven into the well and expanded.

Lead dust emissions can occur when lead powder it is transported via ship-loading facilities. Significant health and environmental hazards of fine lead dusts mean that minimising dust emissions during ship-loading is critical for industry, yet there is limited information on controlling such emissions for lead powder. This study investigated and quantified the impact of moisture on lead dust emissions via both single drop and continuous drop tests in the range 0% to 11% moisture. With increasing moisture, image analysis of single drop tests found increased agglomeration of small plate-like particles into larger spherical clusters. Average particle areas of particles dispersed to the outside of a central core of powder were shown to increase linearly in the range 0% to 11% moisture. Continuous drop tests showed that increasing powder moisture from 0% to 7% could reduce dust emissions by three orders of magnitude, demonstrating the importance and potential benefits of moisture control in ship-loading operations. Modelling of bulk lead powder and lead particle drying were used to identify critical issues and constraints in controlling moisture. Humidity control was identified as a critical control measure during the final stage of ship-loading, where drying rates are fast.

Oil palm residues, such as palm oil empty fruit bunches (PEFBs), are typically abandoned due to high moisture and bulky. Pelletization and downdraft gasification constitute a promising solution for small-scale power and heat production. In this study, the two-dimensional, steady-state computational fluid dynamics (CFD) model of a modified Imbert downdraft gasifier consuming pelletized PEFBs is developed. The detailed kinetic mechanism of biomass devolatilization coupled with particle-scale transport equations is incorporated to enable accurate prediction of the pyrolysis zone in the gasifier. Pelletized-biomass-particles packed bed is simulated by using a porous media model with volumetric species-transport CFD model, which is validated by comparing the prediction of the species volume fractions at the gas outlet with published experimental data. Velocity and temperature profiles of the downdraft gasifier are revealed, along with tar evolution pathline. The effect of the equivalence ratio on the producer gas composition, tar concentration, and cold gas efficiency is investigated. The optimum equivalence ratio is found at 0.30 based on the tar concentration of 5 mg Nm−3 and the cold gas efficiency of 62%.

The pressure drop of a moisture separator in a steam generator is the important design parameter to ensure the successful performance of a nuclear power plant. The moisture separators have a wide range of operating conditions based on the arrangement of them. The prediction of the pressure drop in a moisture separator is challenging due to the complexity of the multi-dimensional two-phase vortex flow. In this study, the moisture separator test facility using the air/water two-phase flow was used to predict the pressure drop of a moisture separator in a Korean OPR-1000 reactor. The prototypical steam/water two-phase flow conditions in a steam generator were simulated as air/water two-phase flow conditions by preserving the centrifugal force and vapor quality. A series of experiments were carried out to investigate the effect of hydraulic characteristics such as the quality and liquid mass flux on the two-phase pressure drop. A new prediction model based on the scaling law was suggested and validated experimentally using the full and half scale of separators. The suggested prediction model showed good agreement with the steam/water experimental results, and it can be extended to predict the steam/water two-phase pressure drop for moisture separators.

The dry air intrusion over India during summer monsoon break phases is well known. It has been argued that this dry air originates over the desert regions of West Asia. Here, we show that a reservoir of saturation deficit air exists over the western and northern Arabian Sea during the summer monsoon season. The monsoon low-level jet (LLJ) that transports the moisture to continental India in the active phase of monsoon, transports the dry air to northern and central India during the break phase. The LLJ undergoes a weakening and broadening before the monsoon break phase in response to increased barotropic instability. The broadening of LLJ leads to an intensification of zonal flow in the poleward flanks and a weakening at the core. The development of a positive meridional SST gradient over the northern Arabian Sea favours an increase in the low-level zonal flow in the north, which advects the moist deficit air across northwest India. The dry air intrusion results in enhanced static stability over northern and central India and strong suppression of convection. Further, the enhanced static stability weakens zonal flow from the northern Arabian Sea region and leads to the demise of the dry air intrusion. Thus, internal mechanisms are responsible for the dry air intrusion over India and its termination during the break phase of the summer monsoon. An index for the dry air intrusion is constructed based on the saturation deficit transport. This dry air intrusion index is used to identify the dry air intrusion events during monsoon breaks during the 1981–2014 period. The statistics show that there were 34 (4) monsoon breaks with (without) dry air intrusion during 1981–2014 period. We also note that the dry air intrusion and the monsoon breaks are happening simultaneously, suggesting that it is difficult to establish a cause-effect relationship.

The sugar industry is an ideal sector for electricity cogeneration due to a large amount of burnable bagasse produce as a by-product. Bagasse produced in the sugar industry always consists of moisture affecting the efficiency of a boiler in the cogeneration plant. In our case study, a cogeneration plant run by bagasse burning found with bagasse moisture problem and suffocating with low power generation for the last few years. The boiler efficiency per tonne of bagasse is currently lower than optimal due to the substantial percentage of water present in the bagasse. A bagasse dryer design for this industry can improve the efficiency of a boiler as well as the cogeneration plant. In this paper, a pneumatic bagasse drying system is proposed to reduce the moisture content of bagasse from 48% to 30%. This work provides a full analysis of bagasse dryer design parameters, including specifications for dryer system components, such as feeders, fan, drying tube, and cyclone. The total bagasse drying system proposed is expected to be fitted within a 6 x 6 x 25 m space to dry 60 tph of bagasse, reducing the moisture content from 48% to 30%, in full compliance with all relevant Australian and company standards. Resumen La industria azucarera es un sector ideal para la cogeneración eléctrica debido a la gran cantidad de bagazo que se produce como subproducto. El bagazo producido en la industria azucarera siempre consiste en humedad que afecta la eficiencia de una caldera en la planta de cogeneración. En nuestro caso de estudio, una planta de cogeneración operada por la quema de bagazo se encontró con un problema de humedad del bagazo y asfixiada con baja generación de energía durante los últimos años. La eficiencia de la caldera por tonelada de bagazo es actualmente inferior a la óptima debido al porcentaje sustancial de agua presente en el bagazo. Un diseño de secador de bagazo para esta industria puede mejorar la eficiencia de una caldera y de la planta de cogeneración. En este trabajo, se propone un sistema de secado neumático de bagazo para reducir el contenido de humedad del bagazo del 48% al 30%. Este trabajo proporciona un análisis completo de los parámetros de diseño del secador de bagazo, incluidas las especificaciones de los componentes del sistema del secador, como alimentadores, ven tiladores, tubos de secado y ciclones. Se espera que el sistema de secado total de bagazo propuesto se instale en un espacio de 6 x 6 x 25 m para secar 60 tph de bagazo, reduciendo el contenido de humedad del 48% al 30%, en total cumplimiento con todas las normas relevantes de Australia y de la empresa.

El compostaje es una alternativa sostenible de valorización de residuos y conversión en abono orgánico. Bajo la hipótesis de que mezclas de residuos tienen características físicas y químicas que modifican el aporte mineral a los cultivos. El objetivo de este estudio fue evaluar las características físico-químicas de tres compostas obtenidas por la mezcla de residuos avícolas y cachaza de la industria azucarera, como alternativa al uso de insumos minerales. Un experimento completamente al azar se estableció con tres tratamientos y tres repeticiones, cada unidad experimental consistió en una pila dinámica de 2 m de largo, 1 m de ancho y 1 m de alto; en Amatlán de los Reyes, Veracruz, México. Temperatura, pH y humedad se registraron. Los elementos se cuantificaron por espectrofotometría de absorción atómica. Los resultados se analizaron con un análisis de varianza y prueba de comparación de medias de Tukey (p≤0.05). La composta de pollinaza presentó las concentraciones mayores de nitrógeno, potasio, calcio, sodio, materia orgánica, carbono total, capacidad de intercambio catiónico y densidad aparente. La mezcla de pollinaza y cachaza tuvo las concentraciones mayores de fósforo y magnesio. La composta obtenida a partir de pollinaza presentó una calidad alta para su uso como abono orgánico, por tanto, puede utilizarse como sustrato de cultivos agrícolas.

The effect of quarry dust-based geopolymer cement on the compressive strength, erodibility, and durability potential of expansive soils has been studied under laboratory conditions. The particular interest was on the geopolymer cement treatment of soils subgrade under hydraulically bound environments. Lateritic soils, which form the compacted foundation of pavements, tend to swell upon contact with moisture and shrink during the drying periods. These two factors affect the response and overtime performance of foundation infrastructure. On the other hand, underground and side rail surface flows affect badly constructed pavements by eroding dislodged foundation materials. However, the need to study the erodibility response of the foundation materials exposed to moisture movements has given rise to the present study. The soils classified as A-7–6, A-7–5, and A-7–5 soils according to AASHTO classification, which are highly plastic and expansive were treated with 10–120% by dry weight of soil and the effect on the compressive strength and durability was studied. Conversely, 10–150% by dry weight was used to study the erodibility response of the treated soils. Both treated frequencies were done at the rate of 10%. The treatment protocol showed that the geopolymer cement (GPC) consistently improved the compressive strength, erodibility, and durability of the treated soils. The results have shown that the green cement has improved the properties of the compacted earth utilized under moisture-bound environment and show the potential to be used as an alternative and sustainable binder for earthworks.

The analysis of the influence of species and the fullness of crop rotations on the ecologization of grain production is given. The most ecologically clean crop rotation is a 2-field grain-fallow: a fallow of black winter wheat. Its productivity and efficiency are slightly inferior to crop rotations, where, in addition to winter wheat, there are spring early and late grain crops. The role of black fallow as a method of preserving moisture, accumulating nutrients, and cleaning the soil from weeds, pathogens, and pests is revealed. The role of black fallow as a method of preserving moisture, accumulating food elements, cleansing the soil from weeds, pathogens diseases and vermins is revealed. It has been established that the advantage of the fallow predecessor in increasing the productivity and technological properties of winter wheat grain in different types of crop rotations is due to the optimization of the elements of soil fertility and the phytosanitary state of agrophytocenosis. Reducing the length of rotation of grain-fallow crop rotations to two or three fields can significantly reduce weediness of crops and abandon the use of herbicides. An increase in the specific gravity weight of black fallow in crop rotations up to 25% makes it possible to increase its efficiency in clearing fields from weeds of the first two fields, reducing the volume of herbicide application by 75%. Thanks to 2, 3-field grain-fallow crop rotations, it is possible to obtain products without the use of mineral fertilizers, chemical plant protection agents, especially against weeds, thereby improving the ecological situation of the environment.

This study investigates the ability of 20 model simulations which contributed to the CMIP6 HighResMIP to simulate precipitation in different monsoon seasons and extreme precipitation events over Peninsular Malaysia. The model experiments utilize common forcing but are run with different horizontal and vertical resolutions. The impact of resolution on the models’ abilities to simulate precipitation and associated environmental fields is assessed by comparing multi-model ensembles at different resolutions with three observed precipitation datasets and four climate reanalyses. Model simulations with relatively high horizontal and vertical resolution exhibit better performance in simulating the annual cycle of precipitation and extreme precipitation over Peninsular Malaysia and the coastal regions. Improvements associated with the increase in horizontal and vertical resolutions are also found in the statistical relationship between precipitation and monsoon intensity in different seasons. However, the increase in vertical resolution can lead to a reduction of annual mean precipitation compared to that from the models with low vertical resolutions, associated with an overestimation of moisture divergence and underestimation of lower-tropospheric vertical ascent in the different monsoon seasons. This limits any improvement in the simulation of precipitation in the high vertical resolution experiments, particularly for the Southwest monsoon season.

Interior insulation of historic buildings is well-studied in Central Europe; however, their conclusions might not be directly applicable to colder climates. Heat, air and moisture (HAM) modelling can be a valuable tool for studying those solutions in different conditions. Recently, incorporating the capillary condensation redistribution (CCR) test into the material characterization process has shown to cause dramatic improvement in correlating hygrothermal modelling results to measurements in certain situations. It is also noteworthy, that the HAM modelling errors made using material data from conventional characterization process can be severely non-conservative. In this article a parametric study of a 51 cm thick mass masonry wall is undertaken to determine the effect of the improved material properties on the reliability of a vapour open ‘capillary active’ autoclaved aerated concrete (AAC) and calcium silicate (CaSi) interior insulation solutions and to compare them to a vapour tight insulation system. A 49-year real weather dataset from Estonia is used. The results show that compared to conventionally characterized material properties the CCR-optimized material data causes more critical conditions directly behind the interior insulation, while having a similar performance in the exterior part of the masonry. The differences occur close to the performance limits and highlight the importance of using the CCR test in material characterization process. The vapour tight and vapour open systems showed a very similar impact on the freeze-thaw cycles and on the maximum ice saturation of the exterior part of the masonry. The vapour open solutions perform better than the vapour tight PIR in terms of frost damage and possible mould growth behind the insulation – even though the advantage has been reduced when using the CCR-optimized material data. Regardless of the insulation solution, a case-specific approach is still required to avoid damaging the original wall and/or the added insulation system.

In the present study, evapotranspiration and moisture adequate index for the 37 mandals of the Srikakulam district for the year 2018 has been estimated. The PET values were very high in the summer season of all the mandals than in the other seasons. The normal PET values were lower than that of the actual PET values showing location specific and better estimation characteristics. This estimation of location-specific PET can be helpful for the drought classification and water management planning within the district. Moisture adequate index of all the mandals has indicated that the district as a whole has a humid/temperate climate; but within the district, mandals report different conditions. This makes it a more relevant tool for drought, microclimatic classification and annual water planning for sustainable agriculture.

The ascomycete Hymenoscyphus fraxineus has spread across most of the host range of European ash with a high level of mortality, causing important economic, cultural and environmental effects. We present a novel method combining a Monte-Carlo approach with a generalised additive model that confirms the importance of meteorology to the magnitude and timing of H. fraxineus spore emissions. The variability in model selection and the relative degree to which our models are over- or under-fitting the data has been quantified. We find that both the daily magnitude and timing of spore emissions are affected by meteorology during and prior to the spore emission diurnal peak. We found the daily emission magnitude has the strongest associations to weekly average net radiation and leaf moisture before the emission, soil temperature during the day before emission and net radiation during the spore emission. The timing of the daily peak in spore emissions has the strongest associations to net radiation both during spore emission and in the day preceding the emission. The seasonal peak in spore emissions has a near-exponential increase/decrease, and the mean daily emission peak is approximately Gaussian.

In agriculture production, soil moisture management is one of the parameters for the sustainable use of natural resources. Soil tensiometers are the instruments used for measuring soil matric potential to monitor soil moisture content. The tensiometer contains a vacuum gauge for the visual indication for irrigation managers to monitor field moisture within the maximum allowable deficit. The vacuum gauge has the limitation that it does not provide its output in the form of an electrical signal, which is used as input for an automatic irrigation system. So, the present work was carried out to develop and evaluate a piezoresistive-based soil moisture sensors system for precise irrigation scheduling through automation devices. The experiment was carried out in the Centre for Protected Cultivation Technology, IARI, New Delhi, and it contains sandy loam soil. The development of a piezoresistive-based sensor for automatic irrigation scheduling can be done by using a piezoresistive sensor, XBee transmitter and receiver, microcontroller, water meter, and relay unit. Once development was completed, it was tested and compared with a conventional tensiometer at different chrysanthemum and tomato crop depths. The relative root mean square error (RRMSE) of soil moisture content for tensiometer and piezoresistive-based soil moisture sensor varied from 9.47 to 19.38 and 7.44 to 18.28, respectively. The coefficient of determination for tensiometer and piezoresistive-based soil moisture varies from 0.71 to 0.72 and 0.82 to 0.84, respectively. The paired t-test was used to compare the developed and conventional tensiometer, and it was found that both sensors were significantly different at a 5% significance level.

This paper presents an experimental investigation on the effect of freeze–thaw cycling on expansive soil slopes with different initial moisture contents. Clay soil from Weifang, China, was remolded and selected to build the expansive soil slope for the indoor slope model tests. A total of five freeze–thaw cycles were applied to the three expansive soil slopes with different moisture contents ranging from 20 to 40%. Variations of the crack developments, displacements, soil pressures and moisture contents of the expansive soil slope with different initial moisture contents during the freeze–thaw cycling were reported and discussed. The results indicate that higher moisture contents can slow the development of cracks and that the soil pressure increases with decreasing temperature. The soil pressure of slope decreases after freeze–thaw cycle, and the change amplitude of soil pressure after freeze–thaw is proportional to water content. The slopes with a moisture content of 20% and 30% shrinks during freezing and expands during thawing, which was named ES-FSTE Model, while the slope with a 40% moisture content shows the opposite behavior. During freeze–thaw cycles, moisture migrates to slope surface. As initial moisture contents increase, the soil heat transfer rate and bearing capacity decreases after five freeze–thaw cycling.

Solar drying is becoming a popular option to replace mechanical dryers due to the high cost of energy, and the increased awareness of consumer orientation to clean energy products. In this study, three different low-cost solar dryers, viz. natural convection dryer (NCD), forced convection dryer (FCD), and heat pump integrated dryer (HPD) were examined, and thin-layer mushroom (agaricus bisporus) drying experiments were carried out on each. In this study, three main topics were determined: (i) to analyse the drying characteristics of mushroom slices in different thicknesses, (ii) to determine the effect of pretreatment on the drying time, (iii) to compare the collector efficiencies. For these purposes, 12 experiments were conducted between 9:00–18:00, the average daily solar irradiance was around 790 W/m2. In 10 drying experiments out of 12, it was observed that the samples were completely dried out within the experiment period, while the drying process of the half-cut mushrooms in NCD and FCD were completed after 18:00. The results show that cutting thin slices reduced the drying time by an average of 40.83 mins. Also, the process of pretreatment caused shorter drying time by an average of 26.66 mins, almost 7% in all cases. The average thermal efficiencies were found 59.74%, 67.66%, and 77.45% for NCD, FCD and HPD, respectively. According to these results, the most affecting factor in overall drying process is found to be drying air which is hot and holds less moisture. In addition, it turned out that the drying rate increases with the increase of the temperature and speed of the drying air.

In the past several decades, the trend of rainfall have been significantly increasing in the Qinghai-Tibet Plateau, which inevitably leads to a change in the surface energy balance processes and thermal-moisture status of the permafrost active layers. However, the influence of mechanisms and associated effects of increasing rainfall on active layers are still poorly understood. Therefore, in this study, a validated coupled numerical water-vapor-heat model was applied for simulating the surface energy components, liquid and vapor water migration, and energy transfer within the permafrost active layer under the action of increasing rainfall in the case of an especially wet year. The obtained results demonstrate that the surface heat flux decreases with the increase in rainfall, and the dominant form of energy exchange between the ground and atmosphere becomes the latent heat flux, which is beneficial for the preservation of permafrost. The increasing rainfall will also cause the migration of liquid and vapor water, and the migration of liquid will be more significant. The liquid and vapor water migration caused by the increasing rainfall is also accompanied by energy transfer. With the increase in rainfall, the decrease in total soil heat flux directly leads to a cooling effect on the soil, and then the upper limit of the frozen soil rises, which alleviates the degradation of permafrost. These results provide further insights into engineering structures, regional ecological climate change, hydrology, and environmental issues in permafrost regions.

Characterizing variability in the global water cycle is fundamental to predicting impacts of future climate change; understanding the role of the Pacific Walker circulation (PWC) in the regional expression of global water cycle changes is critical to understanding this variability. Water isotopes are ideal tracers of the role of the PWC in global water cycling because they retain information about circulation-dependent processes including moisture source, transport, and delivery. We collated publicly available measurements of precipitationδ18O (δ18OP) and used novel data processing techniques to synthesize long (34 yr), globally distributed composite records from temporally discontinuousδ18OPmeasurements. We investigated relationships between global-scaleδ18OPvariability and PWC strength, as well as other possible drivers of globalδ18OPvariability—including El Niño–Southern Oscillation (ENSO) and global mean temperature—and used isotope-enabled climate model simulations to assess potential biases arising from uneven geographical distribution of the observations or our data processing methodology. Covariability underlying theδ18OPcomposites is more strongly correlated with the PWC (r= 0.74) than any other index of climate variability tested. We propose that the PWC imprint in globalδ18OParises from multiple complementary processes, including PWC-related changes in moisture source and transport length, and a PWC- or ENSO-driven “amount effect” in tropical regions. The clear PWC imprint in globalδ18OPimplies a strong PWC influence on the regional expression of global water cycle variability on interannual to decadal time scales, and hence that uncertainty in the future state of the PWC translates to uncertainties in future changes in the global water cycle.