Primary Impact Factor Research Articles

Identifying the toxic mechanisms of emerging electronic contaminations liquid crystal monomers and the construction of a priority control list for graded control

Liquid crystal monomers (LCMs) are identified as emerging organic contaminations with largely unexplored health impacts. To elucidate their toxic mechanisms, support the establishment of environmental discharge and management standards, and promote effective LCMs control, this study constructs a database covering 20,545 potential targets of 1431 LCMs, highlighting 9 key toxic target proteins that disrupt the nervous system and metabolic functions. GO and KEGG pathway analysis suggests LCMs severely affect nervous system, linked to neurodegenerative diseases and mental health disorders, with toxicity variations driven by electronegativity and structural complexity of LCM terminal groups. To achieve tiered control of LCMs, construct toxicity risk control lists for 9 key toxic target proteins, suitable for the graded control of LCMs, management recommendations are provided based on toxicity levels. These lists were validated for reliability and offer reliable toxicity predictions for LCMs. SHAP analysis points to electronic properties, molecular shape, and structural characteristics of LCMs as primary health impact factors. As the first study integrating machine learning with computational toxicology to outline LCMs health impacts, it aims to enhance public understanding of LCM toxicity risks and support the development of environmental standards, effective management of LCM production and emissions, and reduction of public exposure risks.

Improvement on the wire EDM characteristics of zirconia filled Al7050 (Al-Zn-Cu-Mg) alloy composite using Taguchi coupled TOPSIS method

Wire electrical discharge machining (WEDM) is an cutting edge non-traditional techniques for producing complicated 3D forms in rigid materials with greater dimensional accuracy. The aim of the investigation was, to predict the WEDM characteristics of ZrO2 ceramic addition of Al7050 alloy composite by employing Taguchi coupled Technique for order preference by similarity to ideal solution (TOPSIS) approach. The work material was manufactured by stir casting process utilizing 12 wt.% of ZrO2 particulates in Al7050 alloy matrix. The experimental work was carried out as per the L9 (33) orthogonal array design by taking input parameters like pulse current ( Ip), pulse on-time ( Ton) and pulse off-time ( Toff), respectively. The impact of the WEDM parameters on the material removal rate (MRR) and surface roughness (SR) were determined by analysis of variance (ANOVA). Based on the TOPSIS approach, the higher MRR (0.32251 g/min) with lesser SR (3.982 µm) were achieved at the ‘ Ip’ of 25 amps, ‘ Ton’ of 115 µs and ‘ Toff’ of 60 µs. ANOVA results explored that the ‘ Ton’ was identified as the primary impact factor on MRR and SR, subsequently by ‘ Ip’ and ‘ Toff’ with contribution of 44.23%, 36.53%, and 12.16%, respectively. Moreover, the surface topography of the machined composite surface was analyzed through scanning electron microscopy (SEM). It was clearly revealed the formation of surface defects such as craters, micropores, cracks and also the appearance of a recast layer on the machined surface.

Experimental investigation of the temperature field of a frost-penetration tunnel based on a whole life cycle laboratory test

Temperature field evolution plays an essential role in anti-freezing design of frost-penetration tunnels, for which temperature data measured throughout the whole life cycle (100 years) are lacking. The spatial and temporal temperature evolution of a frost-penetration tunnel during the whole life cycle was investigated by using a laboratory test. The test model was designed following some basic fundamental assumptions and similarity principles. The proposed test model was validated using typical cases of the long-term evolution of the temperature fields in cold region tunnels. The evolution features, formation mechanisms and influencing factors were deeply discussed. Experimental results of the model test indicate that a frost-penetration phenomenon occurs in tunnels with positive ground temperature and negative mean annual air temperature. Under negative mean annual air temperature, the freezing circle develops radially towards the surrounding rock and simultaneously develops longitudinally along the tunnel after the tunnel breakthrough. The unfrozen surrounding rock freeze yearly and can develop into permafrost. The primary impact factor of frost penetrations is the positive initial ground temperature and negative mean annual air temperature. The mean annual air temperature has an insignificant effect on the annual temperature amplitude of the surrounding rock, whereas the annual air temperature amplitude has a negligible effect on the mean annual temperature.

Research on the Trade-Offs and Synergies of Ecosystem Services and Their Impact Factors in the Taohe River Basin

The Taohe River Basin is an essential ecological function area in the upper reaches of the Yellow River. Understanding the intricate trade-offs and synergies between ecosystem services (ESs) and exploring the impact of different factors are essential for achieving win–win outcomes in ecosystem management and socioeconomic development. The role of impact factors on the relationship between ESs, nevertheless, is more challenging to spatialize. This study used different models to estimate the net primary productivity (NPP), water yield (WY), and soil conservation (SC), and analyzed synergies and trade-offs between Ess. The spatial heterogeneity of the effects of natural and social factors on the relationships between Ess was explored using a geographic detector and a multi-scale geographically weighted regression (MGWR) model. The results show that: (1) NPP, WY, and SC all exhibit a rising trend, with multi-year averages of 488.99 gC/m2, 157.29 mm, and 1441.51 t/hm2, respectively; (2) NPP–WY and NPP–SC exhibit trade-offs in the majority of regions, while WY–SC are primarily synergistic in the upper and middle reaches, and they have the highest percentage of cropland, forest, and grassland; and (3) precipitation (PRE) has the greatest impact on the trade-off between NPP–WY and NPP–SC in the upper and middle reaches, and the gross domestic product (GDP), population density (POP), and distance from cropland (CROP) are the primary factors determining the synergy between NPP and WY in the lower reaches of the Loess Plateau cropping sector. PRE, digital elevation model (DEM), and CROP are the primary impact factors affecting the synergy of WY–SC. This study may serve as a reference for examining the evolutionary mechanism underlying the trade-offs and synergies between ESs and provide a scientific basis for future ecological environmental protection and regional land management in the Taohe River Basin.

Impact of Microclimate on People’s Experiences and Behaviours in the Cultural Consumption Space: A Case Study of Panjiayuan Antique Market in Beijing, China

Antique and cultural consumption spaces make a great contribution to urban vitality where numerous people walk, stay, and trade. However, how these people’s experiences and behaviours are affected by the microclimate of such spaces has not been studied till now. To address this gap, and using the concept of Post-occupancy Evaluation (POE) as a basis, our study investigated microclimate factors, subjective experiences, and spatiotemporal behaviour patterns in Panjiayuan Antique Market in Beijing, China. Using a mixed-methods approach comprising subjective questionnaires (n = 101), face-to-face interviews (n = 81), spatiotemporal behaviour mapping (n = 8455), and on-site observations, our results showed that microclimates impact people’s experiences and behaviours, with visibility and noise being the two primary impact factors. Most female visitors are more sensitive to the microclimate than male visitors. Furthermore, vendors in the Antique Market preferred to amend their nearby environments to increase the microclimate quality to offer a better experience to visitors around them. This study developed a comprehensive methodology that expands POE in relation to microclimatic factors in the context of cultural consumption spaces. These findings suggest that microclimates have different impacts on people’s experiences and behaviours in different spaces, which should be considered when designing and renewing urban antique markets in the future.

Optimization of underground open intermediary space comfort in TOD complexes: A case study of Chongqing, China.

Rapid urbanization drives social development, but at the same time brings sustainable development Rapid urbanization drives social development, but at the same time brings sustainable development advantages of expanding underground space and relieving urban traffic congestion. High quality TOD complexes with natural elements in the intermediary space have been considered as one of the important means to address sustainable urban development. Nevertheless, intermediary spaces in TOD complexes face various challenges, such as significant contradictory factors in their physical environment spaces. This study classifies the underground open intermediary space into four types according to the characteristics of TOD complexes. And for these four types'Cthe physical environment-generated by various influencing factors of planar geometric, three-dimensional geometric, and detailed construction elements-is simulated using a numerical simulation method based on a static Taguchi experiment. The results demonstrate that space shape is a primary influencing factor for luminous and thermal environments; the window-atrium ratio (W/A ratio) and hole-atrium ratio (H/A ratio) comprise contradictory factors between the luminous and thermal environments of these spaces; profile inclination angle and sunken plaza height are primary impact factors for the acoustic environment; and skylight type has minimal influence on the physical environment. On average, their luminous and acoustic environment comfort can be improved by 200%; whereas, their thermal environment comfort can be improved by 21% and the potential for optimizing it in their shallow space (underground space depth ≤ 10 m) is relatively low. Subsequently, the necessity of comfort optimization as the passive optimization design of underground open intermediary spaces' physical environment in TOD complexes in the future is discussed. Finally, the feasible path and prospect of how to improve the livability and comfort of the spatial physical environment of TOD complexes are discussed and prospected.

Can global warming bring more dust?

In the late twentieth century, global mean surface air temperature especially on land is continuously warming. Our analyses show that the global mean of dust increased since 1980, using the Modern-Era Retrospective Analysis version 2 for Research and Applications (MERRA-2) reanalysis data. This variation of global dust is mainly contributed by the dust increase outside of dust core areas (i.e. high dust mass concentration region). The causes to result in global dust variations are explored. In dust core areas, surface wind is the primary driving factor for surface dust, both of which show no remarkable trends of increase or decrease since 1980. In areas outside of the core areas, especially in arid and semi-arid areas in North and Middle Asia, surface air temperature warming is the primary impact factor causing the dust increase. An increase in surface air temperature is accompanied by enhancement of atmospheric instability which can trigger more upward motion and bring more dust. All 9 Earth System Models (ESMs) for the Aerosol Chemistry Model Intercomparison Project (AerChemMIP) reproduce the reasonable spatial distribution and seasonal cycle of dust in the present day. But only a few models such as BCC-ESM1 and GFDL-ESM4 simulate the increasing trend of dust similar to MERRA-2. While the primary impact of wind in dust core areas, and surface temperature outside of the core areas, especially in middle to high latitudes in Eurasian continent, are presented in most ESMs.

Understanding the Effects of Climate Change on the Distributional Range of Plateau Fish: A Case Study of Species Endemic to the Hexi River System in the Qinghai–Tibetan Plateau

Prediction of species’ potentially suitable distribution areas and their range shifts under future climate change has long been the focus of macroecology and biogeography. Gymnocypris chilianensis of Schizothoracinae and Triplophysa hsutschouensis of Triplophysa are isolated to the Shiyang, Heihe, and Shule Rivers of the Hexi River system, listed from east to west, along the northeastern part of the Qinghai–Tibetan Plateau (QTP). This spatial distribution provides a valuable set of conditions for investigating patterns of habitat suitability and potential impacts of accelerated plateau climate change on endemic plateau fish species. Here, we employed the maximum entropy (MaxEnt) model to first evaluate potentially suitable habitats of the two species and identify the primary impact factors under the current climate based on occurrence records and environmental variables; then, we predicted changes in suitable habitat areas and distribution centers under two representative concentration pathways (RCPs), 2.6 and 8.5, for the future (2050 and 2070). The results showed that annual precipitation and altitude were the two most important environmental factors predicting the suitable habitat of G. chilianensis and T. hsutschouensis. The areas of suitable habitat for G. chilianensis and T. hsutschouensis experienced a sequential westward decrease from the Shiyang River towards the Heihe and Shule Rivers under the current climate conditions. Under future climate changes, the areas of the potential geographical distribution of G. chilianensis and T. hsutschouensis were concentrated eastward towards the Shiyang River, the area of the species’ ancestral origins. Suitable habitat centers of the two species shifted eastward from the Heihe River to the Shiyang River and higher altitude areas. Additionally, G. chilianensis showed a greater reduction in suitable habitat and greater eastward range shift compared to T. hsutschouensis. These findings provide empirical evidence that accelerated climate change on the QTP has severe consequences for endemic populations with restricted and isolated habitats. This study demonstrates that different plateau fish have similarities and differences in their responses to climate change. Our findings also highlight that the effects of climate change must be incorporated into the integrated conservation plans for fish species on the QTP and its adjacent areas.

Microbial and Nonvolatile Chemical Diversities of Chinese Dark Teas Are Differed by Latitude and Pile Fermentation.

Understanding the microbial and chemical diversities, as well as what affects these diversities, is important for modern manufacturing of traditional fermented foods. In this work, Chinese dark teas (CDTs) that are traditional microbial fermented beverages with relatively high sample diversity were collected. Microbial DNA amplicon sequencing and mass spectrometry-based untargeted metabolomics show that the CDT microbial β diversity, as well as the nonvolatile chemical α and β diversities, is determined by the primary impact factors of geography and manufacturing procedures, in particular, latitude and pile fermentation after blending. A large number of metabolites sharing between CDTs and fungi were discovered by Feature-based Molecular Networking (FBMN) on the Global Natural Products Social Molecular Networking (GNPS) web platform. These molecules, such as prenylated cyclic dipeptides and B-vitamins, are functionally important for nutrition, biofunctions, and flavor. Molecular networking has revealed patterns in metabolite profiles on a chemical family level in addition to individual structures.

THEORETICAL ANALYSIS ON HYPERSONIC MHD SHOCK STAND-OFF DISTANCE OF BLUNT BODY

High speed and shock compression behind the bow shock of an aircraft head result in very high temperature, which would subsequently lead to a conductivity plasma flowfield around the vehicle. The plasma gas provides a direct working environment for the application of magnetic field. The magnetohydrodynamic (MHD) flow control, which uses the magnetic field to alter the trajectory of ions or electrons, can improve the aerodynamic characteristics of hypersonic vehicles effectively. As an intuitive aerodynamic phenomenon in the field of hypersonic MHD flow control, shock stand-off distance has attracted close attention from researchers. Under the influence of the applied magnetic field, the shock stand-off distance will change with it, of which the value can directly reflect the effect of the MHD flow control. However, the relevant theoretical models are still limited, and further development in this field is consequently needed. Focusing on dealing with this problem, MHD hypersonic shock stand-off distance of the spherical model is theoretically studied in this paper. By means of radially integrating the continuity equation and applying mathematical method of variable separation to the momentum equation, the analytical expression of MHD shock stand-off distance is obtained. The theoretical analysis was performed under the assumption of low magnetic Reynolds number, and the common-used dipole distribution of magnetic field as applied. The results show that the MHD stand-off distance of shock increases with the increase of magnetic interaction parameter. Moreover, the regularity can be found that as the speed of inflow becomes higher, magnetic interaction parameter can be viewed as the primary impact factor of shock stand-off distance under hypersonic condition. The theoretical model in this work can rapidly evaluate the effect of MHD control, and it can provide theoretical guidance to the design of experiment scheme and the analysis of results.

Indian banks’ nationalization and credit growth: A study of few Indian Banks to identify the impact factors

India has completed 50 years of Indian Banks’ Nationalization. This study examines the role of Banking Nationalization in India’s Credit growth and also analyzes whether it has met its purpose. It assesses the impact of Banking Nationalization on credit growth over the years in rural and small scale sectors. It also covers various troubles which have arisen because of Nationalization like increased NPA and Frauds. Further, primary data is collected to found significant hurdles in achieving the goals of Banking Nationalization. The data for the study is collected through an online survey conducted across four Banks with the sample size of 250 respondents, working in Managerial Positions (Scale I and above). The data is then analyzed using Exploratory Factor Analysis with SPSS to segregate the crucial factors that have impacted the current Indian Banking Structure. It is found that Structural Issues, Poor Corporate Governance, Political Interference, Multiple Regulators, and Anticompetitive Nature are the primary impact factors. These factors along with a mixed review by the respondents on the future of nationalization, clearly suggest that there is an underlying problem with the current banking system which cannot be solved with Banks’ Mergers only. There is no denying that Gradual privatization is the way forward but along the way banking structure needs a major transformation for survival, and have to show innovative approach in recruitment process, regulation, government schemes implementation, service delivery, and even use of technology. The current study also suggests some solutions based on the primary data collected.

Psychological Aspects of Corruption in Public Administration: Case-Study of Ukraine

The purpose of this research was to explore the psychological aspects of corruption in public administration through a combination of methods such as the non-systematic review, a semi-structured interview, a survey questionnaire, and observations of the anti-corruption court hearings. The study employed a case research design using the exploratory research strategy. It relied on a combination of data collection methods. The study was designed as a flow of three basic stages such as identification of psychological factors of corruption, validation of factors, and assessment of relative importance of every factor using the Triangular Assessment Method. It provided first-hand evidence and cases for the course in “Psychological, Behavioural and Economic Triggers of Corruption.” The IBM SPSS Statistics 25.0.0.1. Software was used to process the yielded data. The study found that civil servants’ ambitions to get rich quick, their low self-esteem, psychological dependencies, community-accepted image, sense of impunity were the major psychological aspects pushing the people to corruption in Ukraine. It was also found that the sense of impunity could be considered to be the primary psychological impact factor stimulating corruption actions by the civil servants, specifically. The self-esteem could be regarded as a second important psychological factor of corruption in public administration, which is related to the persons’ vision of their role in the community. The third important factor was ambitions driven by ‘easy money’ and status. The last two factors such as psychological dependencies, the community-accepted image were judged to be the least important ones. Further in-depth research is needed to identify the gender difference in the psychological aspects of corruption in public administration.

Spatial estimate of ecological and environmental damage in an underground coal mining area on the Loess Plateau: Implications for planning restoration interventions

Estimation of the ecological and environmental damage is viewed as an essential tool for effective decision-making in ecological restoration, especially involving high-intensity coal mining and high ecological vulnerability on the Loess Plateau, China. Using the Datong mining area on the Loess Plateau as a case study, we propose an integrated spatial estimation based on surface subsidence prediction, geographic information system, and field survey. The implications for regional ecological restoration are analyzed. Based on this inspection, the magnitude of ecological and environmental damage depended on a combination of risk factors, other than a single factor or evaluation target. Still, the geological hazard was the primary impact factor, especially surface subsidence as a result of underground mining. The results suggest that areas of severe, moderate, and slight damage accounted for 9.87%, 80.09%, and 10.04%, respectively. The methodology used was effective in determining the ecological and environmental damage that is consistent with the spatial distribution of subsidence. The proposed integrated estimation provides targeted measures for active, progressive, and passive interventions to improve and renovate the post-reclamation mining ecosystem and ensure sustainable planning in underground mining areas.

Independent or Influential? Spatial-Temporal Features of Coordination Level between Urbanization Quality and Urbanization Scale in China and Its Driving Mechanism.

The quality and scale of urbanization development are the two main aspects in China’s current urbanization process. By measuring and analyzing the level differences in these two aspects, the healthy development of China’s urbanization and urban–rural integration will be promoted. Based on the quality of urbanization and the scale of urbanization, this paper constructs an evaluation index system for urbanization coordination level. On this basis, this paper analyzes the spatial correlation, spatial difference, and spatial pattern evolution characteristics of urbanization coordination level in 286 sample cities nationwide from 2005 to 2015. Then, by introducing the spatial econometric regression model, this paper discusses the driving mechanism of the spatial and temporal evolution of urbanization coordination level. The results show that: (1) The level of coordination between urbanization quality and urbanization scale shows a strong spatial correlation in space, which is consistent with the actual development status; (2) the level of urbanization coordination shows a trend of evolution from northeast to southwest in the evolution of spatial pattern, but the extent of change is small; and (3) the spatial and temporal pattern of urbanization coordination level is affected by different driving forces, of which internal source is the primary impact factor, followed by administrative level and investment level. In addition, the level of urbanization coordination has a positive spillover effect on the level of urbanization coordination in adjacent areas.

基于MaxEnt模型的雅砻江冬麻豆生境适宜性评价

雅砻江冬麻豆（Salweenia bouffordiana）是近年发现的西南特有冬麻豆属新濒危种，主要分布于四川新龙县的雅砻江河谷。开展其生境适宜性评价及其影响因素分析是对其有效保护的前提和基础。基于2015年8月在雅砻江河谷调查获得的55个分布点，结合24个环境变量数据，利用最大熵模型分析影响雅砻江冬麻豆生境的主要环境因子及其适宜生境预测。结果表明：（1）AUC（曲线下面积）值高于0.9，模型具有较高的准确度，适宜于雅砻江冬麻豆的生境适宜性预测和评估；（2）年均温、最湿月降水、昼夜温差月均值和距河流距离是影响雅砻江冬麻豆生境的最主要环境变量，其最适生境环境变量组合为年均温7.9℃、最湿月降水120-124 mm、昼夜温差月均值13.8℃以及距河流距离33 m；（3）雅砻江冬麻豆的潜在适宜和次适宜生境面积分别约为4.83×10³ hm²和2.37×10⁴ hm²，但仅约7.56×10² hm²的潜在适宜生境和3.28×10³ hm²的潜在次适宜生境位于现有自然保护区管辖范围内。雅砻江冬麻豆的潜在适生区主要沿雅砻江河谷呈狭长的条带状分布，现存区受人类活动影响大，未有生物学地位定级，应尽快确定其生物学保护地位，建立保护小区或社区保护地进行就地保护。;Salweenia bouffordiana is a recently discovered endangered endemic species in southwest China, which mainly distributes along the valley of Yalong River in Xinlong County, Sichuan Province. The effective conservation of S. bouffordiana lies on evaluation of habitat suitability. The MaxEnt model is employed to identify the primary impact factors of the habitat of S. bouffordiana and to predict and evaluate its potentially suitable habitats. The analysis is based on 24 environmental variables of the area and data of field investigation along the Yalong river valley in 55 distribution points. We found that: (1) the AUC (area under ROC curve) value is over 0.9, indicating that the predictive effect of this model is appropriate, and the model can be used to predict and assess the habitat suitability of S. bouffordiana. (2) Mean annual temperature, precipitation of wettest month, mean diurnal temperature range and distance to river are the most predominant environmental variables affecting the habitat suitability of S. bouffordiana. The most suitable combination of environmental variables is a mean annual temperature of 7.9 ℃, a precipitation of wettest month of 120-124 mm, a mean diurnal temperature range of 13.8 ℃ and a distance of 33 m to river. (3) The areas of potential suitable and sub-suitable habitats for S. bouffordiana are 4.83×10³ hm² and 2.37×10⁴ hm², respectively. However, only potential suitable habitats of 7.56×10² hm² and sub-suitable habitats of 3.28×10³ hm² are within the jurisdiction of the existing nature reserves. The potential habitats are limited and mainly distributed along the valley. There are existing human activities to hamper the development and propagation of the population of S. bouffordiana in the current survival areas. In addition, the biological status of S. bouffordiana has not yet been assessed and determined. We suggest that the assessment and determination of biological status for S. bouffordiana should be put on the agenda. Small nature protected areas or community protected areas should be introduced for in-site conservation.

Responses of microbial communities to a gradient of pig manure amendment in red paddy soils

Microbial communities play a key role in maintaining agroecosystem functioning and sustainability, but their response to excessive animal manure application and relevant mechanisms have not been thoroughly elucidated to date. This study investigated the responses of soil bacterial and fungal communities to pig manure (PM) amendment in red paddy soils. High-throughput sequencing revealed that PM amendment significantly reduced the relative abundance of Acidobacteria yet increased that of Bacteroidetes, Ignavibacteriae, Firmicutes, and Rozellomycota. The Cu and available phosphorus were the primary impact factors influencing bacterial and fungal diversity, respectively. Bacterial alpha-diversity tended to sharply decrease when the content of soil Cu was >30.70 mg kg−1, while fungal alpha-diversity did not continuously increase when the content of soil available phosphorus was >82.84 mg kg−1. Bacterial communities with a wider niche breadth showed significantly lower structural variation, whereas fungal communities with a narrower niche breadth showed greater variation in community structure. Soil heavy metals, primarily Cu and Zn, were the primary factors that affected bacterial communities, whereas soil fungal communities were mainly influenced by soil phosphorus. Bacterial and fungal communities showed distinct co-occurrence patterns, with bacterial communities showing a higher degree, a clustering coefficient, and betweenness centrality, but a lower closeness centrality. The findings highlighted that bacteria and fungi responded differently to PM amendment because of their discrepant niche breadth, interspecific relationships, and different tolerance to heavy metal and soil nutrient.

Health-Related Quality of Life of Medical Students in a Chinese University: A Cross-Sectional Study.

Thus far, there have been no studies adapting the Mandarin 36-Item Short Form Health Survey (the SF-36) questionnaire for assessment of the health-related quality of life (HRQOL) of medical students in China. This study aimed to explore the feasibility of that form and analyse its impact factors. The study involved 498 randomly sampled medical students stratified by their academic majors, and general information was collected. The effective response rate was 83.53%. Split-half reliability coefficients and Cronbach’s α coefficients of seven dimensions were more than 0.7 with the exception of the social function (SF) dimension. Spearman’s correlation analysis results were basically in accord with the theoretical construction of the SF-36. The HRQOL of the students was scored from 43.83 (the RE dimension) to 93.34 (the PF dimension). The primary impact factors affecting the HRQOL of medical students included major, sleep quality, degree of physical exercise, post-exercise status, relationship with roommate, and satisfaction with family. These findings suggested that the Mandarin SF-36 was reliable for measuring the HRQOL, that the HRQOL of medical students in a Chinese university was relatively poor, and that its improvement requires concerted efforts.

Experimental investigation on thermal characteristics of transcritical CO2 heat pump unit combined with thermal energy storage for residential heating

A preliminary experimental investigation was carried out to analyze the thermal characteristics of a transcritical CO2 air source heat pump unit with thermal energy storage for residential heating. The primary impact factors such as discharge pressure, ambient temperature, supply/return water temperature were considered. Also, a performance comparison of the combined system with the CO2 air source heat pump unit without thermal energy storage was presented. It was found that the maximum coefficient of performance (COP) of the CO2 air source heat pump unit decreased by 18.8%, and the optimum discharge pressure and the throttle loss increased by 14.7% and 47.5%, respectively, as the water temperature at the inlet of the gas cooler increased from 35 to 45 °C. Additionally, the results also indicated that the COP of the combined system was 17% higher than that of the CO2 air source heat pump unit. However, it was worth noted that the water flow rate should be adjusted according to the supply water temperature in the practical application so as to meet the thermal comfort for user. The experimental results demonstrated that thermal energy storage as a sub-cooler is a promising technology for reducing the throttle loss and improving the COP of the combined system, and is helpful to promote the CO2 air source heat pump application for space heating in cold regions.

Low-temperature phase transitions of sodium aluminate solutions

A series of low-temperature phase transitions of sodium aluminate solutions were studied by differential scanning calorimetry (DSC) and Raman spectroscopy. The results indicate that NaOH concentration is a primary impact factor for the binary eutectic point and ice melting temperature of sodium aluminate solutions with low NaOH concentration. In addition, the phase transition process of sodium aluminate solutions with low NaOH concentration from 123.15 to 283.15 K is divided into four steps: non-crystal to crystal, ternary eutectic reaction, binary eutectic reaction and ice melt. The projection phase diagram of NaOH-Al(OH)3-H2O system at low temperature was plotted, in which the ternary eutectic temperature for sodium aluminate solutions is 183.15 K.

Degradation of sulfadiazine in drinking water by a cathodic electrochemical membrane filtration process

In this study, a novel electrochemical membrane filtration (EMF) process was proposed to degrade sulfadiazine (SDZ) in drinking water, and the oxidation mechanisms, kinetics, byproducts and primary impact factors were investigated. In the EMF process, a novel membrane was used as the cathode and two graphite plates were used as anodes. Five oxidation byproducts including 4-OH-sulfadiazine or 5-OH-sulfadiazine, 2-aminopyrimidine, 4-amino-N-carbamimidoyl benzene sulfonamide and 2,5-dihydroxypyrimidine were identified. Possible degradation pathways for SDZ were proposed, and OH and ▪ were recognized to be the major reactive oxygen species contributed for SDZ degradation. The degradation of SDZ by EMF followed pseudo-first-order kinetics in batch experiment and the rate constant increased as the applied voltages increased. Compared with the batch experiment, the flow-through mode of EMF slowed SDZ degradation, and the degradation rate also decreased as the flux increased. However, on the base of mass balance calculations more SDZ was degraded in flow-through mode as compared with that in batch experiment. Finally, the degradation of SDZ in natural waters from a municipal drinking water treatment plant was investigated with flow-through mode, and the result shows that the degradation rate (79%) was slightly lower than that obtained for deionized water due to the low conductivity of real-world water systems.