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Enhanced proton conductivity of viscose-based membranes via ionic modification and dyeing processes for fuel cell applications

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Journal of Materiomics 2023年第3期9卷 587-600页

作者： Haoyu Wu Tianchi zhou Bin Wang Jinli Qiao Flexible Functional Materials Institute Yancheng Institute of Technology1 Hope Avenue RoadYancheng224051China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Environmental Science and EngineeringDonghua University2999 Ren'min North RoadShanghai201620China Shanghai Engineering Research Center of Marine Renewable Energy Shanghai201306China Shanghai Institute of Pollution Control and Ecological Security Shanghai200092China

Proton exchange membranes(PEMs),which are crucial fuel cell parts,play an important role in the field of energy ***,the further development of conventional PEMs based on synthetic polymers is greatly limited by high energy consumption and difficult *** this work,we reported the fabrication of a novel viscose-based PEM via cationic modification and dyeing treatment with the reactive dyes ***-efficiency proton transmission channels can be constructed due to the for-mation of the complex internal three-dimensional network of the as-prepared viscose-based PEM.Hþconductivity(sHþ)and water uptake are intensively investigated by changing the cationic agents and KE-7B1,and the maximum sHþreaches 44.19 mS/cm at 80℃and 98%relative humidity(RH).Furthermore,the prepared membrane shows the lowest calculated activation energy value(12.25 kJ/mol),indicating that both Grotthuss and Vehicle mechanisms play an important role in ionic *** membrane chemical structure and micromorphology are analyzed and the proton transmission modes are explored in detail,supplemented with research on the hydrophilic/hydrophobic characteristics and crystallinity of the *** application stability of the membranes is also evaluated analyzing the thermal,mechanical,and oxygen resistance properties,and the results show that all the prepared membranes can maintain good thermal stability within 200℃.The maximum tensile strength reaches 42.12 MPa,and the mass losses of the membranes soaked in 30%(in mass,same below)H_(2)O_(2)solution for 120 h can be restricted to 10%.Therefore,as a novel PEM,the obtained dye viscose-based membranes show great potential for application in fuel cells.

关键词： Membrane Viscose Reactive dyes Proton conductivity Fuel cell

Assessing the Performance of CMIP6 Models in Simulating Droughts across Global Drylands

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Advances in Atmospheric Sciences 2024年第2期41卷 193-208页

作者： Xiaojing YU Lixia ZHANG Tianjun zhou Jianghua ZHENG LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University of Information Science&TechnologyNanjing 210044China University of Chinese Academy of Sciences Beijing 100049China College of Geography&Remote Sensing Sciences Xinjiang UniversityUrumqi 830046China

Both the attribution of historical change and future projections of droughts rely heavily on climate modeling. However,reasonable drought simulations have remained a challenge, and the related performances of the current state-of-the-art Coupled Model Intercomparison Project phase 6(CMIP6) models remain unknown. Here, both the strengths and weaknesses of CMIP6 models in simulating droughts and corresponding hydrothermal conditions in drylands are *** the general patterns of simulated meteorological elements in drylands resemble the observations, the annual precipitation is overestimated by ~33%(with a model spread of 2.3%–77.2%), along with an underestimation of potential evapotranspiration(PET) by ~32%(17.5%–47.2%). The water deficit condition, measured by the difference between precipitation and PET, is 50%(29.1%–71.7%) weaker than observations. The CMIP6 models show weaknesses in capturing the climate mean drought characteristics in drylands, particularly with the occurrence and duration largely underestimated in the hyperarid Afro-Asian areas. Nonetheless, the drought-associated meteorological anomalies, including reduced precipitation, warmer temperatures, higher evaporative demand, and increased water deficit conditions, are reasonably reproduced. The simulated magnitude of precipitation(water deficit) associated with dryland droughts is overestimated by 28%(24%) compared to observations. The observed increasing trends in drought fractional area,occurrence, and corresponding meteorological anomalies during 1980–2014 are reasonably reproduced. Still, the increase in drought characteristics, associated precipitation and water deficit are obviously underestimated after the late 1990s,especially for mild and moderate droughts, indicative of a weaker response of dryland drought changes to global warming in CMIP6 models. Our results suggest that it is imperative to employ bias correction approaches in drought-related studies over drylands by using CMIP6 o

关键词： droughts hydrothermal conditions drylands CMIP6 model evaluation

Stability of the Phase Separation State for Compressible Navier-Stokes/Allen-Cahn System

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 45-74页

作者： Ya-zhou Chen Hakho Hong Xiao-ding Shi Department of Mathematics College of Mathematics and PhysicsBeijing University of Chemical TechnologyBeijing100029China Institute of Mathematics State Academy of SciencesPyongyangKorea

This paper is concerned with the large time behavior of the Cauchy problem for Navier-Stokes/AllenCahn system describing the interface motion of immiscible two-phase flow in 3-D. The existence and uniqueness of global solutions and the stability of the phase separation state are proved under the small initial perturbations. Moreover, the optimal time decay rates are obtained for higher-order spatial derivatives of density,velocity and phase. Our results imply that if the immiscible two-phase flow is initially located near the phase separation state, then under small perturbation conditions, the solution exists globally and decays algebraically to the complete separation state of the two-phase flow, that is, there will be no interface fracture, vacuum, shock wave, mass concentration at any time, and the interface thickness tends to zero as the time t → +∞.

关键词： Navier-Stokes/Allen-Cahn system existence uniqueness large time behavior decay rate

Urban Agglomerations in China: Characteristics and Influencing Factors of Population Agglomeration

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Chinese Geographical Science 2023年第4期33卷 719-735页

作者： CAO Yongwang ZHANG Rongrong ZHANG Dahao zhou Chunshan School of Geography and Planning Sun Yat-sen UniversityGuangzhou 510006China

Urban agglomeration(UA)is an advanced spatial economic form formed and developed in the process of rapid industrialization and urbanization,and an important carrier of urbanization and economic *** economy has developed rapidly in the recent decades of China,and the UAs have also developed ***,as a large population country,the population distribution and changes of UAs in China has unique *** the fifth,sixth and seventh population census data,spatial auto-correlation and spatial econometric models,we analyzed the spatial-temporal evolution characteristics and influencing factors of population agglomeration in China’s *** revealed that:1)from 2000 to 2020,the population gradually converged into UAs,and the characteristics of population agglomeration in different development degree of UAs *** higher the development degree of UA,the higher the population agglomeration ***,UAs are the main area with the most significant population agglomeration degree,and the spatial autocorrelation show that the cities with similar degree tend to be concentrated in *** urban population gathering in UAs has a certain positive spillover effect on population size of neighboring cities.2)Economic development and social conditions factors are important factors affecting population agglomeration degree in *** main factors of population gather into UAs are similar with the outside UAs,but the positive promotion of urbanization rate and proportion of tertiary industry in GDP on population agglomeration of UAs in China are enhancing from 2000 to ***,the other factors,such as high-quality public services,good urban living environment conditions,high-quality medical and educational resources,are also important factors to promote urban population gather into *** study provides a basis for formulating the development planning of UAs in China,and enriches the relevant theoretical research of population evol

关键词： urban agglomerations(UAs) population agglomeration influencing factors spatial econometric models China

Group decision-making method based on entropy and experts cluster analysis

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Journal of Systems Engineering and Electronics 2011年第3期22卷 468-472页

作者： Xuan zhou Fengming Zhang Xiaobin Hui Kewu Li Engineering College Air Force Engineering UniversityXi'an 710038P.R.China

According to the aggregation method of experts＇ evaluation information in group decision-making,the existing methods of determining experts＇ weights based on cluster analysis take into account the expert＇s preferences and the consistency of expert＇s collating vectors,but they lack of the measure of information *** it may occur that although the collating vector is similar to the group consensus,information uncertainty is great of a certain ***,it is clustered to a larger group and given a high *** this,a new aggregation method based on entropy and cluster analysis in group decision-making process is provided,in which the collating vectors are classified with information similarity coefficient,and the experts＇ weights are determined according to the result of classification,the entropy of collating vectors and the judgment matrix ***,a numerical example shows that the method is feasible and effective.

关键词： group decision-making judgment matrix entropy information similarity coefficient cluster analysis.

Gene flow among wild and cultivated common walnut(Juglans regia)trees in the Qinling Mountains revealed by microsatellite markers

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Journal of Forestry Research 2021年第5期32卷 2189-2201页

作者： Huijuan zhou Peng Zhao Keith Woeste Shuoxin Zhang College of Forestry Northwest A&F UniversityYanglingShaanxi 712100People’s Republic of China Key Laboratory of Resource Biology and Biotechnology in Western China Ministry of EducationCollege of Life SciencesNorthwest UniversityXi’anShaanxi 710069People’s Republic of China USDA Forest Service Hardwood Tree Improvement and Regeneration Center(HTIRC) Department of Forestry and Natural ResourcesPurdue University715 West State StreetWest LafayetteIN 47907USA

Patterns of gene flow and gene introgres sion can be used to assess the risk of genetic pollution of wild forest trees from widespread cultivated trees.A comprehensive understanding of the genetic relationships and levels of gene flow among wild and cultivated common walnut(Juglans regia)has become an urgent *** twelve microsatellite markers,we investigated the genetic diversity and gene flow between cultivated and wild trees of *** in the Qinling Mountains,China.A high level of genetic variation was detected in both cultivated and wild *** mean number of alleles per locus was *** heterozygosity(HO)and expected heterozygosity(HE)were 0.777 and 0.800,*** of mother trees was not by nearest neighbors,and a paternity of 60.7%of offspring evaluated could not be assigned to a local,sampled *** flow from cultivated trees to wild trees was infrequent(5.4%),and selfing rates ranged from zero to 25.0%.Male parents were located from 0 to 1005 m from their female partners,with an average pollination distance of 285.1 *** results are discussed in light of the cultivated species’diversity,outlining the frequent spontaneous genetic contributions from the wild to the cultivated *** addition,the pollen flow parameters provide useful information about the dynamics of pollen movement within *** populations.

关键词： Genetic diversity Juglans regia Mating patterns Microsatellites Pollen flow

Mantle sources of Cenozoic volcanoes around the South China Sea revealed by geochemical and isotopic data using the principal component analysis

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Journal of Oceanology and Limnology 2023年第2期41卷 562-574页

作者： Shuangshuang CHEN Zewei WANG Rui GAO Yongzhang zhou School of Earth Sciences and Engineering Sun Yat-sen UniversityGuangzhou 510275China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China Guangdong Provincial Key Lab of Geological Processes and Mineral Resources Guangzhou 510275China State Key Laboratory of Marine Environmental Science Xiamen UniversityXiamen 361102China Department of Earth and Space Sciences Southern University of Science and TechnologyShenzhen 518055China State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China

Principal component analysis(PCA)was employed to determine the implications of geochemical and isotopic data from Cenozoic volcanic activities in the Southeast Asian region,including China(South China Sea(SCS),Hainan Island,Fujian-Zhejiang coast,Taiwan Island),and parts of Vietnam and *** analyzed 15 trace element indicators and 5 isotopic indicators for 623 volcanic rock samples collected from the study *** principal components(PCs)were extracted by PCA based on the trace elements and Sr-Nd-Pb isotopic ratios,which probably indicate an enriched oceanic island basalt-type mantle plume and a depleted mid-ocean ridge basalt-type spreading *** results show that the influence of the Hainan mantle plume on younger volcanic activities(13 Ma)at the same location in the Southeast Asian *** was employed to verify the mantle-plume-ridge interaction model of volcanic activities beneath the expansion center of SCS and refute the hypothesis that the tension of SCS is triggered by the Hainan *** study reveals the efficiency and applicability of PCA in discussing mantle sources of volcanic activities;thus,PCA is a suitable research method for analyzing geochemical data.

关键词： volcanic rocks geochemical indicators mantle source principal component analysis South China Sea

Tolerance and safety evaluation of sodium sulfate:A subchronic study in laying hens

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Animal Nutrition 2021年第2期7卷 576-586页

作者： Bing Liu Jiaming Zhu Qin zhou Dongyou Yu College of Animal Sciences Zhejiang UniversityHangzhou310058China State Key Laboratory of Food Science and Technology and Synergetic Innovation Center of Food Safety and NutritionJiangnan UniversityWuxi214122China

Sodium sulfate(Na2SO4)is a readily available chlorine-free source of sodium,which could be used to reduce sodium chloride to maintain the ratio between chlorine and sodium in poultry *** supplementation with excessive levels of Na2SO4 might be detrimental to bird's health and per-formance.A subchronic study was carried out to investigate the potential adverse effects of an accidental oversupply of Na2SO4 in the diets of laying *** hundred and fifty 21-week-old Hy-Line White layers were randomly assigned to 5 treatments with 6 *** birds were fed diets supplemented with 0(control),0.3%,0.6%,1.5%,and 3.0%Na2SO4 for 8 *** perfor-mance,egg quality parameters,clinical blood parameters,histopathology,intestinal barrier func-tions,and intestinal microflora composition were *** clinical signs of intoxication or mortality were observed during the experimental *** results of this study showed that the optimal levels of Na2SO4(0.3%to 0.6%)significantly improved the laying rates,average daily egg mass,and eggshell quality of hens compared to the control(P<0.05).However,3.0%Na2SO4 produced negative effects on laying performance,eggshell quality,blood biochemistry,and partic-ularly on liver and kidney pathology,and intestinal morphology and barrier functions compared with the *** minor changes were observed in clinical blood parameters of hens receiving 1.5%Na2SO4,these were not considered to be of toxicological significance due to the absence of any organ pathological changes in *** conclusion,our results indicated that a Na2SO4 concentration of 1.5%was non-deleterious to laying hens after a daily administration for 56 d,namely that dietary supplementation of up to 5 times the maximum recommended dose is safely tolerated by laying hens.

关键词： Sodium sulfate Tolerance Histopathology Intestinal function Laying hen

A Fast Physical Layer Security-Based Location Privacy Parameter Recommendation Algorithm in 5G IoT

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China Communications 2021年第8期18卷 75-84页

作者： Hua Zhao Mingyan Xu zhou Zhong Ding Wang Information Engineering University Zhengzhou 450001HenanChina National Digital Switching System Engineering and Technological Research Center Zhengzhou 450002HenanChina

The 5G IoT(Internet of Things,IoT)is easier to implement in location privacy-preserving *** terminals in distributed network architecture blur their accurate locations into a spatial cloaking region but most existing spatial cloaking algorithms cannot work well because of man-in-the-middle attacks,high communication overhead,time consumption,and the lower success *** paper proposes an algorithm that can recommend terminal’s privacy requirements based on getting terminal distribution information in the neighborhood after cross-layer authentication and therefore help 5G IoT terminals find enough collaborative terminals safely and *** approach shows it can avoid man-in-the-middle attacks and needs lower communication costs and less searching time than 520ms at the same *** has a great anonymization success rate by 93%through extensive simulation experiments for a range of 5G IoT scenarios.

关键词： cross-layer authentication location privacy parameter recommendation 5G IoT