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Because of its unique geographical properties, the Yaoquanshan area of Wudalianchi City, Heilongjiang Province, contains rich mineral water resources. We have carried out much research on the mineral water in the Yaoquanshan area of Wudalianchi City, which has also been supplemented by of previous studies. In this paper, through a controlled audio geoelectromagnetic method, geological drilling, groundwater level monitoring and water quality analysis, the structure, regional geology, hydrogeology and water geochemistry, as well as the characteristics of the distribution of metasilicate mineral water and natural soda water, the formation mechanism and the recharge, runoff and excretion of groundwater in the study area, are discussed. The results can provide a theoretical basis for the exploitation and utilization of mineral water resources in the southern region of the Wudalianchi Pharmaceutical Spring Mountain. [ABSTRACT FROM AUTHOR]

Copyright of Acta Geoscientica Sinica is the property of Acta Geoscientica Sinica Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Microplastics have been widely detected in the natural water environment, which brings inevitable risks to the water ecosystem and human health. However, the understanding of the potential impact of microplastics on aquatic animals, plants, and human health is still limited, and technical methods to control microplastic pollution in natural water are still rare. Hence, this paper summarizes the progress of research on microplastic pollution in water systems in terms of microplastic source, attributes, distribution characteristics, environmental effects, and prevention and control methods according to the relevant research reports on water microplastic pollution. It also expounds the basic ways for the prevention, control, and treatment of water microplastics, and looks forward to the research direction of water microplastic pollution in the future. The results show that the abundance of fresh water microplastics in China is higher than that in other regions, but the pollution level of marine microplastics is at the middle level. Compared with other countries, the pollution degree of microplastics in aquatic organisms in China is at the middle and lower level, but the spatial heterogeneity is more obvious. Through hydraulic control and the substitution of degradable plastic products, water microplastic pollution can be greatly reduced. This paper can provide a reference basis for the formulation of microplastic pollution prevention and control in China. [ABSTRACT FROM AUTHOR]

In order to explore the regional evaluation and distribution characteristics of enterprises' technological innovation capabilities, this paper introduces the Logistic model, a commonly used model in ecology to analyze the law of population growth. Moreover, this paper uses satellite-based symbiosis mode, network-based symbiosis mode, and network-satellite compound symbiosis mode to establish models to solve the stable equilibrium point, and summarize the symbiosis stability conditions of innovation clusters in various modes. In addition to this, this paper combines the Internet of Things and big data technology to study the regional evaluation and distribution characteristics of enterprise technological innovation capabilities, and build an intelligent model based on the Internet of Things and big data. The research results show that the research system of regional evaluation and distribution characteristics of enterprise technological innovation capabilities based on the Internet of Things and big data proposed in this paper has good results. Finally, this paper puts forward relevant suggestions with the support of the model proposed in this paper. [ABSTRACT FROM AUTHOR]

Guided by entering the deep sea and achieving deep marine development in marine construction, the factors hindering marine construction cannot be ignored. Strong ocean winds have a devastating impact on tasks such as ship navigation, carrier aircraft take-off and landing, naval operations and military exercises, and affect the planning of sea routes and the development of the long-distance sea. This paper uses ERA5 wind field data and key climate indices to conduct a systematic analysis of catastrophic winds in the global ocean using methods such as climate statistical analysis, the Theil–Sen trend method, Pearson correlation and contribution rate calculation. It points out the spatiotemporal distribution, variation trend, climate index correlation and contribution rate characteristics of strong winds occurrence (SWO) and hopes that the results of this study can serve as a guide for maritime route planning and provide technical assistance and decision-making support for marine development and other needs. The results show the following: The high global SWO occurs in the Southern Ocean, the North Atlantic, the North Pacific, near Taiwan, China, the Arabian Sea and other locations, with the strongest SWO in summer. The growth trend of SWO in the Southern Ocean is strongest, with decreasing regions near the Arabian Sea and the Bay of Bengal, and the growth trend is reflected in all four seasons. The climate indices with the strongest correlation and highest contribution to the global SWO are AAO (Antarctic Oscillation) and EP–NP (East Pacific–North Pacific pattern) with a correlation between −0.5 and 0.5 and a contribution rate of up to −50%~50%. [ABSTRACT FROM AUTHOR]

As a new visual consumer space, the "Internet-famous space" provides a new perspective for the study on urban space in the mobile Internet era. Based on the data of the Douyin (the Chinese version of Tiktok) platform, this paper quantitatively measures the popularity and the distribution characteristics of Internet-famous spaces in the main urban area of Hangzhou. It is concluded that the distribution of Internet-famous spaces shows a spatial pattern of multi-core concentration, with spatial popularity decreasing from the urban center to the suburbs. The hot spot areas of Internet-famous spaces are mainly distributed in the functional nodes of the city, and the concentration characteristics of the internal spaces in these different areas show great differences. [ABSTRACT FROM AUTHOR]

Urban-scale green spaces have been a central topic as of late, but community-scale green spaces are overlooked in urban studies. This paper takes community green spaces in the main urban area of Beijing as the case to quantitatively interpret the spatial-temporal patterns of their service efficiency and distribution characteristics. The measurement section of the paper includes two parts: the first part compares the applicability of two major green space service efficiency measurement methods on the community scale and determines that the Shortest Time Distance method performs better in describing the spatial-temporal patterns of service efficiency. The second part applies the Time Distance Entropy method to initially identify the locational relationship between community green spaces and neighboring residential buildings, then proposes the Green Space Distribution Coefficient method based on this relationship to analyze the 'courtyard', 'mixed', and 'centralized' distribution types alongside the transition relationships between them, and the spatial-temporal patterns of distribution characteristics are measured. The results of service efficiency reveal that the community paradigms transform from 'humanistic-oriented' to 'benefit-oriented' as the Shortest Time Distance measurement values show an ascending trend with the passage of years and the outward expansion of the ring roads. The results of distribution characteristics reveal that the community residential culture transforms from 'closeness' to 'detachment' as Green Space Distribution Coefficient measurement values show a descending trend under the same conditions. Based on the measurements, this paper further provides several optimizing strategies for community green spaces in the central urban area of Beijing. [ABSTRACT FROM AUTHOR]

Copyright of Transactions of Nanjing University of Aeronautics & Astronautics is the property of Editorial Department of Journal of Nanjing University of Aeronautics & Astronautics and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Previous studies on scientific literature rarely considered discrimination, i.e., the extent to which the content of some research is different from that of others. This paper contributes to the quantitative methods used for the research on the discrimination of article content via the proposal of the article discriminative capacity (ADC). Academic articles included in the Chinese Social Sciences Citation Index (CSSCI) in the discipline of Library and Information Science (LIS) are used as research objects. First, the most suitable text representation model is chosen to better represent the content of articles, thereby improving the performance of ADC. Then, in-depth quantitative analyses and evaluations of the articles from the perspectives of the source journals, publication years, authors, themes, and disciplines are conducted in conjunction with the ADC. The results demonstrate that the combination of the ADC with the BERT model can better identify a single article with high discriminative capacity. Articles in the fields of Information Science and Cross-LIS are found to have relatively low average ADC values. In contrast, articles in the fields of Library Science and Archives Science have high average ADC values. Articles with high ADC values have diverse themes and distinctive keywords, and can reveal new methods and promote interdisciplinarity. On the contrary, articles with low ADC values have similar research themes, and favor traditional, commentary, and conventional research. Moreover, scholars with high discriminative capacity are more willing to explore new fields, instead of being confined to traditional LIS research. This work may help promote the diversity of academic research and complement the evaluation system of academic articles. One major limitation of this study is that it only used data from Chinese databases. [ABSTRACT FROM AUTHOR]

ObjectiveThis paper aims to analyzes the shock response characteristics of a large-scale floating shock platform (LFSP) subjected to underwater explosion. MethodsThe acoustic-solid coupling approach is used as the basis for the numerical simulation. The validity of the calculation method used in this paper is verified by comparing the experimental data with simulation, and the shock response characteristics of the location of interest in the LFSP's inner bottm plating is investigated in terms of its longitudinal section distribution as well as the effects of changes in the horizontal distance to the blast source on the whole shock environment of LFSP's inner bottom structure, thereby the LFSP's shock response prediction formula is obtained by fitting method.ResultsThe results indicate that the shock response characteristics of the locations (i.e. outer and inner plates, longitudinal section in centre plane) distributed along the longitudinal section of the inner bottom structure are basically the same. The shock response amplitude of the front and back sides of the floating platform are small, while that of the middle is large. The shock responses of the outer and inner plates differ, and the spectral velocity of the inner plate is greater than that of the outer plate, while the spectral displacement of the outer plate is greater than that of the inner plate.ConclusionsThe measurement points within the inner bottom plating are excited so spikes appear in the shock spectral lines, resulting in the spectral velocity of the inner plate is higher than that of the outer plate. The horizontal distance of bottom plate to the blast source is smaller so the shock response is stronger, bringing about a greater spectral displacement of the outer plate than that of the inner plate.

Neonatal sepsis (NS) has no specific clinical manifestations and blood culture analysis requires a long period of time. Knowledge of prevalent bacterial isolates and their antibiotic susceptibility is crucial when choosing an empirical therapy to decrease morbidity and mortality. This literature review summarizes the distribution characteristics and antimicrobial resistance of bacterial pathogens associated with bloodstream infections in Chinese neonates, and thus serves as a reference for pediatricians. The full-text journal database, CNKI, was searched using the key words "neonatal", "sepsis", and "bacterial pathogen" to retrieve relevant literature published from 2016 up to April 2018. The following data were extracted from the selected papers: title, pathogen collection time, care unit name, province (city), distribution of bacterial pathogens among bloodstream infections, and antimicrobial resistance of major pathogens. A total of 86 articles were searched, of which 30 complied with the study requirements and thus were included in the review; all were retrospective studies. The articles covered a total of 4098 bacterial strains from 24 cities (2494 Gram-positive bacteria, 1429 Gram-negative bacteria, 176 fungi). Among the Gram-positive bacteria, the four pathogens with the highest detection rates were coagulase-negative staphylococci (CoNS) (40.23%), Streptococci (6.81%), Enterococci (6.10%), and Staphylococcus aureus (S. aureus) (5.15%); among the Gram-negative bacteria, Klebsiella (14.52%), Escherichia coli (12.12%), Enterobacter cloacae (1.90%), and Pseudomonas (1.41%) had the highest detection rates. The detection rate of Candida and other fungi was 4.29%. Among the pathogens with high clinical detection rates, S. epidermidis and S. aureus are highly resistant to both erythromycin and penicillin. Antibacterial drugs with high efficacy for both S. epidermidis and S. aureus include vancomycin, ciprofloxacin, gentamicin, linezolid, rifampicin, and tetracycline. Klebsiella pneumoniae and Escherichia coli are highly resistant to ampicillin, but there are drugs with high efficacy for both, including imipenem, piperacillin/tazobactam, aminoglycosides (gentamicin, amikacin), and quinolones (levofloxacin, ciprofloxacin). In contrast to the drug resistance data reported by the China Antimicrobial Resistance Surveillance System (CARSS) in 2017, the detection rate of methicillin-resistant S. aureus (MRSA) and methicillin-resistant coagulase-negative staphylococci (MRCoNS) in the blood cultures of neonates with sepsis exceeded the national average drug resistance level (p <.01). The resistance rate of K. pneumoniae to third-generation cephalosporins was higher than the national average drug resistance level (p <.01), but this organism was most sensitive to carbapenems (carbapenem resistance refers to resistance to any of imipenem, meropenem, or ertapenem). The resistance of Escherichia coli to quinolones was better than the national average level (p <.01). Medical care-related infections in neonatal intensive care units (NICUs) were more often caused by CoNS than by S. aureus and Gram-negative bacteria. Vancomycin remains the preferred drug for treating confirmed infections, because most isolated CoNS are resistant to β-lactam drugs including penicillin. For Gram-negative enteric bacteria, aminoglycoside and carbapenem were sufficient for treatment. Compared to the CARSS data on bacterial resistance, the data in this review on the resistance of pathogens causing NS were not favorable. The next goal in antibiotic management in NICUs must be to develop strategies to reduce the use of antibiotics. [ABSTRACT FROM AUTHOR]

Introduction: Massilia bacteria are widely distributed and have various ecological functions. Preliminary studies have shown that Massilia is the dominant species in constructed wetland ecosystems, but its species composition and distribution in constructed wetlands are still unclear. Methods: In this paper, the in-house-designed primers were used to construct a 16S rDNA clone library of Massilia. The RFLP sequence analysis method was used to analyze the diversity of Massilia clone library and the composition of Massilia in sewage, substrate, plant rhizosphere, plant phyllosphere and air in a constructed wetland sewage treatment system. Redundancy analysis (RDA) and canonical correspondence analysis (CCA) were used to analyze the correlation between environmental factors and the population characteristics of Massilia in the corresponding environment. The dominant species of Massilia were analyzed for differences. Results: The results showed that the 16S rDNA clone library in primer 5 worked well. According to the clone library diversity index analysis, the richness of Massilia varied significantly in different environments in different seasons, where the overall summer and autumn richness was higher than that in the spring and winter. The relative abundance of 5 Massilia in the constructed wetland ecosystem was greater than 1% in all samples, which were M. alkalitolerans, M. albidiflava, M. aurea, M. brevitalea, and M. timonae. The seasonal variation of dominant genera was significantly correlated with environmental factors in constructed wetlands. Discussion: The above results indicated that the species of Massilia were abundant and widely distributed in the constructed wetland ecosystem, and there were significant seasonal differences. In addition, the Massilia clone library of constructed wetland was constructed for the first time in this study and the valuable data of Massilia community structure were provided, which was conducive to the further study of microbial community in constructed wetland. [ABSTRACT FROM AUTHOR]

Post-fracturing shut-in, as an important means of improving the energy efficiency of fracturing fluid, has been widely used in the development process of unconventional reservoirs. The determination of the shut-in duration is key to the effectiveness of shut-in measures. However, the distribution characteristics of the fracturing fluid during the post-fracturing shut-in period in unconventional reservoirs, such as the Chang 7 reservoir, were not clear, and the shut-in duration needed further optimization. Therefore, this paper employed low-field nuclear magnetic resonance (NMR) technology to study the distribution characteristics of the fracturing fluid during the post-fracturing shut-in period in unconventional reservoirs and optimized the shut-in duration. The study showed that the Chang 7 reservoir had a complex pore structure and relatively low porosity and permeability. During the shut-in process, the filtrate was distributed in pore throats with radii ranging from 0.0012 μm to 0.025 μm. Pore throats with radii ranging from 0.003 μm to 0.07 μm acted as dynamic pore throats in the process of imbibition displacement. When the shut-in duration for the Chang 7 segment was 7 days, the growth rate of the retained volume of fracturing fluid filtrate was the highest. When the shut-in duration was 10 days, there was no oil displacement in the medium and large pores, and the retained volume of filtrate was lower than that at 7 days shut-in, indicating that an optimal shut-in duration would be 7 days. This study can provide theoretical and technical support for the development of unconventional reservoirs. [ABSTRACT FROM AUTHOR]

This study aims to analyze the spatial distribution characteristics and innovation efficiency of national agricultural science and technology parks (NASTPs) and identify the main influencing factors on the parks' innovation and development. The goal is to optimize the allocation of science and technology innovation resources in these parks, promote national agricultural science and technology innovation, and enhance the quality of agricultural development. To achieve this, the paper employs spatial analysis methods and a three-stage DEA-Tobit model to conduct both macro and micro-level analyses. The research findings are as follows: (1) Distribution characteristics: NASTPs tend to exhibit a uniform distribution at the national scale, but at the provincial level, their distribution appears clustered and uneven. Specifically, three high-density areas and two sub-high-density areas have emerged on the eastern side of the Hu line, displaying a decreasing trend from east to west. (2) Innovation efficiency: By excluding the influence of environmental factors and random interference, the lack of scale efficiency (SE) emerges as the primary reason for the generally low innovation efficiency of NASTPs. (3) Environmental factors: Science and technology training exhibits a negative correlation with innovation efficiency in NASTPs. Leading enterprises, income level, innovation support, and demonstration and promotion show positive correlations with IE in NASTPs. To promote national agricultural science and technology innovation and enhance the quality of agricultural development, it is recommended, based on a central-level development perspective, to focus on the layout of the northeast and northwest regions. At the local level, expanding the scale of key enterprise inputs and increasing the demonstration and promotion of scientific and technological achievements are recommended. Additionally, at the NASTPs level, guiding the construction of a national agricultural high-tech industry demonstration zone is advised. [ABSTRACT FROM AUTHOR]

Groundwater resources are an essential component of global water resources. Long-term consumption of groundwater exceeding the standard levels for iron and manganese can lead to chronic diseases, posing a threat to human health. The Sanjiang Plain is the largest swamp wetland area in China and has high levels of iron and manganese in the groundwater, but the cause still needs to be clarified. Based on the results of water quality tests of 41 groundwater samples in the Eastern Sanjiang Plain, this paper analyzes the distribution characteristics and causes of iron and manganese from the perspectives of the original strata environment, redox conditions, pH conditions, and hydrochemical indicator factors in the research area, using statistical methods and GIS technology. The results show that high iron and manganese content in groundwater is prevalent in the Eastern Sanjiang Plain, and the exceedance rate of manganese is higher than that of iron (87.80% and 82.90%, respectively). The primary sources of iron and manganese in groundwater are iron and manganese minerals in the original strata environment. Influenced by factors such as acidic conditions, reducing environment, and rich organic matter, insoluble high-valent iron and manganese oxides are reduced to low-valent and soluble divalent iron and manganese. At the same time, groundwater's high mineralization and evaporation concentration are conducive to increased iron and manganese content, while the influence of human activities is small. [ABSTRACT FROM AUTHOR]

Copyright of Arid Land Geography is the property of Chinese Academy of Sciences, Xinjiang Institute of Ecology & Geography and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The Grand Canal of China, as a traffic artery in ancient China, has exerted profound influence on the development of the cities, towns and rural settlements along it. Now, with China's rapid urbanization, numerous settlements along the canal are confronted with problems like slow cognition of the cultural heritage, loss of the local culture and damage of historical relics. Hence, research on the protection and updating of the settlement space along the canal is in urgent need. This paper, targeting the settlement space along the Grand Canal Tianjin Section, adopts such research methods as the Historical GIS analytical method, the kernel density estimation method and the average nearest-neighbor method to quantitatively analyze the evolution stage and distribution characteristics of the settlement space along the Grand Canal Tianjin Section from the perspective of cultural relics to reveal the in-situ rules of evolution of the settlement space. The research result indicates that the spatial-temporal evolution of the settlement space can be divided into five such periods of the settlements along the canal as the pre-canal period, the rudimentary period, the development period, the mature period and the transformation period. Each period features different cultural relics and settlement distribution patterns. The research shows that the natural geographical environment, the grain transportation projects and management systems, the wasteland opening, grain growing and military defense policies, the agricultural, commercial and economic growth and the migration and folk culture are the influencing factors of the spatial evolution of the settlement space along the Grand Canal Tianjin Section. [ABSTRACT FROM AUTHOR]

The energy distribution in molten pool is highly related to the quality of the weld formation in aluminum alloy welding. The forming defects in the weld are often improved by adjusting the molten pool dynamic behaviors affected by energy distribution. Therefore, the energy distribution characteristics in the molten pool during the welding of aluminum alloy with oscillating laser in the "∞" shaped path are explored in this paper. The pore defects are found to be greatly reduced in welds from the oscillating laser welding of aluminum alloy compared to those from non-oscillating laser welding. The corresponding distribution characteristics of energy in the molten pool of welding with oscillating laser are obtained and analyzed. The dynamic behaviors and forming process of welds under welding conditions of different distribution characteristics of energy in the molten pool are discussed. The obtained results are in good agreement with the experimental results. Therefore, the proposed method can provide the desired energy distribution for stable dynamic behaviors of molten pool to improve welding quality. [ABSTRACT FROM AUTHOR]

In recent years, antibiotics have been listed as a new class of environmental pollutants. Tetracycline antibiotics (TCs) used in human medical treatment, animal husbandry and agricultural production are the most widely used antibiotics. Due to their wide range of activities and low cost, their annual consumption is increasing. TCs cannot be completely metabolized by humans and animals. They can be abused or overused, causing the continuous accumulation of TCs in the ecological environment and potential negative effects on non-target organisms. These TCs may spread into the food chain and pose a serious threat to human health and the ecology. Based on the Chinese environment, the residues of TCs in feces, sewage, sludge, soil and water were comprehensively summarized, as well as the potential transmission capacity of air. This paper collected the concentrations of TCs in different media in the Chinese environment, contributing to the collection of a TC pollutant database in China, and facilitating the monitoring and treatment of pollutants in the future. [ABSTRACT FROM AUTHOR]

Temperature distribution and the deformation behavior under temperature are important parameters in the design and evaluation of concrete pavements. In this paper, in order to study the horizontal distribution of the temperature effect on rubberized concrete pavement (RCP), the distribution differences of temperature, temperature gradient and strain at different horizontal locations were analyzed based on fiber Bragg grating test technology. The relationships between temperature and strain and between temperature gradient and strain were also investigated. The results show that within a cycle of temperature or temperature gradient change, the time of temperature increase or temperature gradient increase is only 1/4 of the whole cycle, significantly less than the time of the temperature or temperature gradient decrease. Comparing the center, edges and corner of the pavement, the horizontal distribution of temperature and temperature gradients in the RCP is uneven, and the greatest negative temperature gradient is experienced at the corner of the pavement, which is 25 °C·m−1 greater than the temperature gradient at the center. The negative temperature gradient at the corner of the concrete pavement exacerbates the bottom deformation at the center and edge of the pavement, especially in the X-axis direction at the center and in the Y-axis and Z-axis directions at the edge. The relationships between temperature and horizontal strain at the center and edge of the RCP have a significant hysteresis effect and are markedly stronger than those at the corner. Moreover, when the temperature gradient is less than −23.4 °C·m−1 or greater than 14.5 °C·m−1, the curling effect at the edge of the RCP is more obvious. [ABSTRACT FROM AUTHOR]

RNA methylation is a crucial epigenetic modification widely present in RNA molecules, and has been demonstrated to play significant roles in diverse biological processes. Advances in detection and sequencing technologies have facilitated the identification of RNA modification‐related regulatory proteins and their corresponding biological functions. In this paper, we provide a brief overview of several RNA methylation, including N6‐methyladenosine(m6A), 5‐methylcytidine(m5C), N1‐methyladenosine(m1A), N7‐methylguanosine(m7G) and N6, 2'‐O‐dimethyladenosine(m6Am), about their regulatory proteins, distribution patterns and biological functions, and mainly outline the advantages and limitations of the representative sequencing techniques. Finally, we discuss the technological challenges and future perspectives in RNA transcriptomic field. [ABSTRACT FROM AUTHOR]

Copyright of Petroleum Geology & Recovery Efficiency is the property of Petroleum Geology & Recovery Efficiency and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper aims to investigate the effect of internal and external humidity differences on the distribution characteristics of the carbonated zone of cement-based materials. Carbonation tests with ambient humidity and pore water saturation as the influencing factors were implemented. The calcite content of the mortar along the depth of carbonation was presented. The rationality of the carbonation model was verified by the calcite test results, and the effect of internal and external humidity differences on the carbonation zone distribution of cement-based materials was analyzed by the model. The results showed that the test results of calcium carbonate and the simulation results can clearly distinguish the completely and partly carbonated zones of cement-based materials. The effect of pore water saturation on the distribution of the carbonated area was conspicuous, but the difference in pore water saturation cannot change the variation of the extent of the carbonated zone with ambient humidity. The change regularities of fully and partly carbonated zones with humidity differences were obtained. [ABSTRACT FROM AUTHOR]

Copyright of Natural Gas Geoscience is the property of Natural Gas Geoscience and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Villages in rural areas are regional complexes with multiple characteristics and functions. Rural tourism has become an important driver in the revitalization of rural China. The Ministry of Culture and Tourism of China approved the first group of 320 National Key Villages for Rural Tourism (NKVRT) in 2019. This paper takes these first 320 NKVRT as the research object, using GIS as a tool to analyze and discuss their spatial distribution characteristics, and identifies how they are affected by certain influencing factors. The results show the following: (1) the spatial distribution of NKVRT in China exhibits obvious differences, generally characterized as dense in the southeast and sparse in the northwest. Moreover, the development of rural tourism is closely related to the level of urbanization and economic development in the surrounding areas. (2) The core density of NKVRT presents the spatial distribution characteristics as "independent and evident in the high-value areas, gradually decreasing outward in the remaining grade areas." The spatial pattern of core density has a high degree of similarity with the agricultural strategic pattern of the main functional areas of the country. (3) The spatial distribution characteristics of NKVRT are associated with climate, population, topography, precipitation, elevation, land use, and economic development. The spatial distribution characteristics of different types of NKVRT are also distinct. These research results emphasize that the development and growth of rural tourism in China should not only consider the balance between regions, but also the influence of both natural factors and human factors. [ABSTRACT FROM AUTHOR]

The transparent envelope structure has huge energy-saving potential, which is the key point to reduce building energy consumption and improve the thermal building environment. The solar radiation transmitted through the transparent envelope structure (transmitted solar radiation) is reflected, scattered and absorbed by the indoor surface, which has a significant impact on the heat gain of the building. In this paper, firstly, the diffuse radiation received by different depths of various indoor surfaces is measured by experimental tests, and the distribution function of transmitted diffuse solar radiation (TDSR) on the indoor surface is established. Secondly, the diffuse solar radiation received by the indoor and outdoor surfaces in different seasons is continuously monitored; the variation of TDSR with time is analyzed, and the distribution function of TDSR on indoor surface with time is proposed. Finally, based on the temporal and spatial distribution characteristics of diffuse radiation under different weather conditions, the variation of TDSR with the weather is studied, and the distribution function of TDSR on the indoor surface with weather changes is established. The distribution function of the TDSR on the indoor surface under different depths, time and weather conditions obtained in this study can supplement and improve the theory of building heat gain and load, and help accurate simulation of building energy consumption. [ABSTRACT FROM AUTHOR]

Copyright of Shanghai Land & Resources / Shanghai Guotu Ziyuan is the property of Editorial Board of Shanghai Land & Resources and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

As an emerging business form of tourism development, homestays also play an important role in China's rural revitalization and tourism transformation and upgrading, and has attracted increasing social attention. At present, Chongqing is the city with the largest number of homestays in China. Taking Chongqing as a case-study area, based on the homestay data of the Baidu map, this paper comprehensively uses the methods of spatial analysis, multiple regression and geographical weighted regression to thoroughly analyze the regional characteristics and influencing factors of homestay distribution in Chongqing. The results show that: (1) the nearest-neighbor index R of homestay distributions in Chongqing and all regions is one, which shows an obvious agglomeration type. (2) In addition to being highly concentrated in the central urban area, three secondary high-density areas are also formed in the surrounding areas of the central urban area, and there is a trend of concentration and contiguity. The spatial distribution densities of the two urban agglomerations in Southeast and Northeast Chongqing are very low, and the overall distributions are extremely uneven. (3) The factors, such as tourism resource endowment, economic development, service industry development, traffic location, consumption demand and social development conditions, have significant impacts on the distribution pattern of homestays, and the impacts of each factor on the layout of homestays has obvious spatial heterogeneity. Analyzing and revealing the temporal and spatial characteristics and dynamic mechanism of homestays has an important theoretical value and practical significance for better serving the new urbanization plan and implementing the strategy of urban–rural integration and rural revitalization. [ABSTRACT FROM AUTHOR]

The quality of the marine environment is increasingly affected by human activities, especially the ecological environment of nearshore waters is deteriorating year by year, and the production of fishery resources is constantly decreasing. As a result, fish eggs and larvae have gradually been highly valued in recent years. Through cross-sectional investigation and research on the spring and autumn seasons in the northern waters of the South China Sea, this paper preliminarily explores the distribution characteristics and seasonal changes of fish eggs and larvae in the northern South China Sea. As clearly revealed by the survey and research results, the species and resource density of fish eggs and larvae in spring are higher than those in autumn. Moreover, the high-density areas of fish eggs and larvae are predominantly concentrated in the nearshore waters, with a comparatively small number in the nearshore areas. In spring, there are principally open-sea species, while in autumn, there are nearshore species. After October in the northern part of the South China Sea, the water temperature began to decrease, and fish entered a low peak period of spawning. This study has reference value for the sustainable development of fisheries in the sea area as well as the protection and rational utilization of marine living resources. [ABSTRACT FROM AUTHOR]

Copyright of Asian Journals of Ecotoxicology is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper summarizes previous research on Shiba-mune (Japanese turf house), and the distribution characteristics of their roof plants were clarified through field surveys. There are about 600 Shiba-mune in eastern Japan, mainly in Iwate and Aomori prefectures, of which 90% are in Iwate. In all prefectures except Iwate and Aomori, most of Shiba-mune were designated as cultural properties and have been preserved. However, some of the buildings designated as cultural properties could no longer maintain their Shiba-mune. As for the distribution of roof plants, sod was found in all areas where Shiba-mune were distributed. On the Pacific side of the Tohoku region and in the inland mountainous areas, lilies, tawny daylilies, green onions, and Chinese chives were observed. Roof iris was seen in the Kanto Plain area. Iwahiba was seen around the Kanto Mountains. [ABSTRACT FROM AUTHOR]

Climate change has been a hot topic in recent years. However, the urban microclimate is more valuable for research because it directly affects people's living environments and can be adjusted by technological means to enhance the resilience of cities in the face of climate change and disasters. This paper analyses the literature distribution characteristics, development stages, and research trends of urban microclimate research based on the literature on "urban microclimate" collected in the Web of Science core database since 1990, using CiteSpace and VOSviewer bibliometric software. It is found that the literature distribution of the urban microclimate is characterized by continuous growth, is interdisciplinary, and can be divided into four stages: nascent exploration, model quantification, diversified development and ecological synergy. Based on the knowledge mapping analysis of keyword clustering, annual overlap, and keyword highlighting, it can be predicted that the research on foreign urban land patch development has three hot trends—multi-scale modelling, multi-factor impact, and multi-policy guidance. The study's findings help recognize the literature distribution characteristics and evolutionary lineage of urban microclimate research and provide suggestions for future urban microclimate research. [ABSTRACT FROM AUTHOR]

It is very important to calculate the interference of high voltage direct current (HVDC) grounding current with pipelines accurately and take proper protective measures to ensure energy transmission safety. There is still a lack of systematic research into related prediction methods that consider the nonlinear polarization on the interface between the soil and pipelines. In this paper, a methodology is proposed for calculating the coupling voltage and current on buried pipelines induced by grounding currents that accounts for nonlinear polarization based on the method of moments (MoM) and the finite element method (FEM). The validity of the proposed mathematical model is verified by a scale experiment. The interference distribution characteristics under different parameters are analyzed using the proposed method. The results show that the relationship between the maximum leakage current density and the electrode grounding current satisfy the linear function. The corrosion area becomes more concentrated as the grounding current increases. The corrosion area range increases substantially as the distance increases, whereas the influence degree decreases substantially. Both the maximum leakage current density and corrosion risk area are positively correlated with the soil resistivity. [ABSTRACT FROM AUTHOR]

Perinereis aibuhitensis (Grube, 1878) lives in marine sediments of estuary or shoal areas, where substrate has some crucial environmental factors affecting its burrowing and distribution. In order to provide basic data for the habitat selection and suitability evaluations of the artificial aquaculture of P. aibuhitensis, this paper conducted a quantified analysis of its burrowing ability and explored its behavioral preferences in different substrates, including mud (<75 μm), fine sand (125-250 μm), medium sand (250-500 μm), coarse sand (500-2 000 μm), gravel (2 000-4 000 μm) and ceramsite (4 000-8 000 μm). The research results revealed that substrate grain size significantly affected the burrowing time, burrowing rate, burrowing depth and distribution rate (P<0.01). Moreover, P. aibuhitensis demonstrated preferential selections relating to substrate grain sizes, had higher burrowing ability in ceramsite, mud and fine sand compared with other substrates. The strongest burrowing ability and the highest distribution rate were observed in ceramsite. The study indicated that P. aibuhitensis was sensitive to substrate grain size, which also had an impact on its burrowing process and population distribution. In the natural sea, substrates mainly composed of mud and fine sand are fit for aquaculture and stock enhancement. Based on behavioral preferences and ecological rehabilitation function of P. aibuhitensis, this paper proposes a symbiotic system of marine animals and halophytes, and constructs an ecosystem model of "Marine fish-Halophytes-Perinereis aibuhitensis" with P. aibuhitensis as the link. [ABSTRACT FROM AUTHOR]

Copyright of Environmental Science & Technology (10036504) is the property of Editorial Board of Environmental Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advances in Earth Science (1001-8166) is the property of Advances in Earth Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Sciencepaper is the property of China Sciencepaper and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Purpose The purpose of this paper is to provide the details of developments to research works in the distribution characteristics of the air gaps within firefighters’ clothing and research methods to evaluate the effect of air gaps on the thermal protective performance of firefighters’ clothing.Design/methodology/approach In this paper, the distribution of air gaps within firefighters’ clothing was first analyzed, and the air gaps characteristics were summarized as thickness, location, heterogeneity, orientation and dynamics. Then, the evaluation of the air gap on the thermal protective performance of fighters’ clothing was reviewed for both experimental and numerical studies.Findings The air gaps within clothing layers and between clothing and skin play an important role in determining the thermal protective performance of firefighters’ protective clothing. It is obvious that research works on the effects of actual air gaps entrapped in firefighters’ clothing on thermal protection are comparatively few in number, primarily focusing on static and uniform air gaps at the fabric level. Further studies should be conducted to define the characteristic of air gap, deepen the understand of mechanism of heat transfer and numerically simulate the 3D dynamic heat transfer in clothing to improve the evaluation of thermal protective performance provided by the firefighters’ clothing.Practical implications Air gaps within thermal protective clothing play a crucial role in the protective performance of clothing and provide an efficient way to provide fire-fighting occupational safety. To accurately characterize the distribution of air gaps in firefighters’ clothing under high heat exposure, the paper will provide guidelines for clothing engineers to design clothing for fighters and optimize the clothing performance.Originality/value This paper is offered as a concise reference for researchers’ further research in the area of the effect of air gaps within firefighters’ clothing under thermal exposure. [ABSTRACT FROM AUTHOR]

Collaborative efforts to reduce pollution and carbon emissions are a notable feature of the current era. Achieving the “pollution reduction” and “carbon reduction” dual-driven new development model is the inevitable requirement and significant practical measure for building a new development pattern and realizing a comprehensive green transformation of economic and social development. The synergistic effects between pollution reduction and carbon reduction (PRCR) have been demonstrated. However, the measurement and quantitative analysis of the coupling coordination degree (CCD) of PRCR have not received enough attention. Therefore, the evaluation index system was constructed based on the scientific connotation of PRCR, and the CCD of PRCR in cities along the Yellow River Basin (YRB) from 2009 to 2018 was measured quantitatively by constructing the coupling coordination model in this paper. In addition, we comprehensively investigated its spatial pattern, distribution characteristics, and evolution trend using ESDA, Kernel density estimation, and Markov chain. The primary findings can be summarized as: (1) PRCR levels and their CCD fluctuated and increased in the YRB, with “east-high and west-low” spatial differentiation characteristics, and the coupling phenomenon of “pollution reduction is hindered and carbon reduction is lagging”. (2) There is a phenomenon of “spatial club” clustering in the coordination degree of PRCR in the YRB, with most cities in the downstream areas belonging to the type of high-high clustering, while the middle and upstream areas had the opposite type. (3) The CCD of PRCR in the whole and upper reaches of the YRB have transformed from low-level divergence to high-level convergence. (4) Spatial geographic factors have a significant spillover effect on the evolution of the CCD of PRCR, and there is a phenomenon of the “Matthew effect”. This paper provides a comprehensive framework for analyzing the synergistic effects between PRCR, and the research findings can also provide insights for other regions.

[Objectives] The paper was to investigate the garden greenbelt in 30 sample plots such as parks, roads, communities, etc. in Shijiazhuang City. [ Methods] The species, abundance and frequency of weeds in the greenbelt of public gardens were recorded through point-line-surface investigation, and typical plants were sampled. [Results] There were 56 species of alien invasive plants in garden greenbelts of Shijiazhuang City, belonging to44 genera and 20 families. In terms of life form, herbaceous plants were absolutely dominant, accounting for 92.8% of the total. The most alien invasive plants were native to America, accounting for 66.1% of the total. In terms of introduction path, the plants introduced artificially and unintentionally accounted for almost half. The species and quantity of alien invasive plants were related to the size of greenbelt area, the length of the build time of the surveyed plot, the composition structure of greenbelt and the level of green management and protection. There was larger distribution of alien invasive plants in the sample plots with large greenbelt area, long build time, herbaceous-dominated greenbelt and low level of green management and protection. Among the 56 alien invasive plants, 3 plants were toxic. From the perspective of invasiveness, the alien invasive plants in the garden greenbelt of Shijiazhuang City could be divided into 5 levels: invasive alien species of malignant consequences, invasive alien species of severe consequences, invasive alien species of partial consequences, invasive alien species of average consequences, and invasive alien species to be observed. [Conclusions] This study will provide a reference for the prevention and control of alien plant invasion, and lay a foundation for the prevention and control of existing invasive plants. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Chongqing University of Technology (Natural Science) is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nonferrous Metals (Mining Section) is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Pore structure characteristics of ultra-low permeability reservoirs are studied in this paper. The impact of pore structure characteristics on permeability and reservoir development effect is analyzed by conventional and constant-rate mercury penetration experiments. The results show that the frequency curve of pore radius distribution of ultra-low permeability reservoirs has little change with permeability. The average pore radius in ultra-low permeability reservoirs with different permeability levels had little difference, and its distribution ranges from 98.5 to 110.1 μm. With decrease of permeability, the frequency distribution curves of throat radius and pore-throat ratio change significantly. The peak value of throat radius curve moves to the left and increases significantly, and the average throat-radius distribution decreases from 2.33 to 0.91 μm. However, the impact of pore-throat ratio on permeability is contrary to that of throat radius. Both throat radius and pore-throat ratio has strong correlation with permeability, and they are in exponential relationship. With the in-depth study, it is found that seepage capacity of reservoirs is restricted mainly by throat radius and pore-throat ratio. When throat radius decreases to less than 1 μm and pore-throat ratio increases more than 130, permeability decreases sharply and obviously. When permeability is less than 2 × 10−3μm2, the proportion of fine throats and medium throats under the condition of effective water injection is significantly lower, and the production of single well and the recovery efficiency by water flooding in ultra-low permeability reservoirs are low. The study explains effectively the fundamental reason for the poor efficiency of production and recovery of ultra-low permeability reservoirs from the mechanism. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Geological Hazard & Control is the property of China Institute of Geological Environmental Monitoring (CIGEM) Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)