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Integrative Zoology 2023年第2期18卷 316-332页

作者： Wei Zhou Xu LI Key Laboratory for Conserving Wildlife with Small Populations in Yunnan Southwest Forestry UniversityKunmingChina

Studies onﬁsh fauna should not only focus onﬁsh composition and the comparison ofﬁsh composition among the study region and adjacent regions,but should also explore the origin and uniqueness of different taxa as well as the substitution of genera and species.In this study,the value ofﬂoristic presence method was modiﬁed and renamed the value ofﬁsh fauna presence(VFFP)method.The speciﬁc steps of the VFFP method and the traditionalﬁsh fauna analysis(TFFA)method were reﬁned and standardized.Then,the VFFP and TFFA methods were applied to study theﬁsh fauna of the upper and middle portions of the Mekong River basin.The results indicate that the TFFA method reﬂects the families(subfamilies)and genera that constitute the main body ofﬁsh in the studied river basin.The results of the VFFP method show which families(subfamilies)and genera are representative for the basin.Therefore,combining the TFFA and VFFP methods to analyze the composition ofﬁsh fauna can reﬂect the characteristics ofﬁsh fauna from different perspectives.The case study shows that theﬁsh fauna of the Mekong River is a part of theﬁsh fauna of Southeast Asia.Although it shows some similarities to the composition of South Asianﬁsh fauna,it does not belong to the South Asianﬁsh fauna as a whole,and is essentially different from the East Asianﬁsh fauna.This study provides an objective,quantitative,and veriﬁable method for studyingﬁsh fauna.

关键词： ﬁsh composition ranking Southeast Asia traditionalﬁsh fauna analysis value ofﬁsh fauna presence

Morphological,electromagnetic and absorbing properties of GR/Fe_(93.5)Si_(3.5)La_(1)Ce_(2) composite powders

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Journal of Rare Earths 2023年第1期41卷 130-139页

作者： Wei Zhou Chaochao Zeng Zhenghou Zhu College of Material Science and Engineering Nanchang UniversityNanchang 330031China

In this study,the morphological,electromagnetic and absorbing properties of GR/Fe_(93.5)Si_(3.5)La_(1)Ce_(2) composite powders were systematically investigated.The composite powders was prepared by highenergy ball milling.X-ray diffractometer(XRD) and Raman spectroscopy analyses confirm the presence of α-Fe and graphene in the composite powders.Scanning electron microscopy(SEM) observation shows that the composite powders have a flake morphology.The electromagnetic and absorbing properties of the composite powders were analyzed with a vector network analyzer.When the milling time and graphene content are 12 h and 1 wt%,respectively,the composite powders exhibit the best absorbing property.For 1.0 wt% GR/Fe_(93.5)Si_(3.5)La_(1)Ce_(2) composite at 0.3 GHz,the ε’and ε" are 77.76 and124.73,and the μ’and μ" are 6.09 and 2.83.Its tanδ_(ε),tanδ_(μ) and tanδ reach 0.63,13.80 and 14.43,respectively,which basically increased the tanδ by more than 2 times compared with other composite powders.This indicates that the composite powder has excellent wave absorption performance.Meanwhile,the analysis shows that the loss mechanism of the composite powder is mainly relaxation loss,conduction loss,eddy current loss and natural resonance.Therefore,this composite powder provides a new approach for the development of wave absorbing materials.

关键词： Graphene Microwave absorption Electromagnetic High-energy ball milling Rare earths

Discrete element method study of hysteretic behavior and deformation characteristics of rockfill material under cyclic loading

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2023年第4期24卷 350-365页

作者： Mingchun LIN Guanqi WANG Jian zhou Wei Zhou Ni AN Gang MA State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Institute of Water Engineering Sciences Wuhan UniversityWuhan 430072China Power China Chengdu Engineering Co. Ltd.Chengdu 610072China Power China Kunming Engineering Co. Ltd.Kunming 650051China

Granular geomaterials under different loading conditions manifest various behaviors,such as hysteresis.Understanding their hysteretic behavior and deformation characteristics is the basis for establishing a constitutive relation with excellent performance in deformation prediction.The deformation characteristics of crushable particle materials are analyzed through a series of cyclic loading tests conducted by numerical simulation.The hysteretic behavior is investigated from a particle scale.The increase in particles with contacts less than two may be responsible for the residual strain,and the particle breakage further promotes particle rearrangement and volume contraction.Both the accumulation of plastic strain and the resilient modulus are found to be related to confining pressures,stress levels,cyclic loading amplitudes,and the number of cycles.The plastic strain accumulation can be written as a function of the number of cycles and an evolution function of resilient modulus is proposed.

关键词： Granular material Discrete element method(DEM) Plastic deformation Cyclic loading Hysteretic behavior

Bioinspired Nanostructured Superwetting Thin-Films in a Self-supported form Enabled“Miniature Umbrella”for Weather Monitoring and Water Rescue

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Nano-Micro Letters 2022年第2期14卷 174-189页

作者： Shan Li Peng Xiao Wei Zhou Yun Liang Shiao-wei Kuo Tao Chen Key Laboratory of Marine Materials and Related Technologies Zhejiang Key Laboratory of Marine Materials and Protective TechnologiesNingbo Institute of Materials Technology and EngineeringChinese Academy of SciencesNingbo 315201People’s Republic of China School of Chemical Sciences University of Chinese Academy of Sciences19A Yuquan RoadBeijing 100049People’s Republic of China Department of Material and Optoelectronic Science National Sun Yat-Sen UniversityKaohsiung 804TaiwanPeople’s Republic of China

Two-dimensional(2D)soft materials,especially in their self-supported forms,demonstrate attractive properties to realize biomimetic morphing and ultrasensitive sensing.Although extensive efforts on design of self-supported functional membranes and integrated systems have been devoted,there still remains an unexplored regime of the combination of mechanical,electrical and surface wetting properties for specific functions.Here,we report a self-supported film featured with elastic,thin,conductive and superhydrophobic characteristics.Through a well-defined surface modification strategy,the surface wettability and mechanical sensing can be effectively balanced.The resulted film can function as a smart umbrella to achieve real-time simulated raining with diverse frequencies and intensity.In addition,the integrated umbrella can even response sensitively to the sunlight and demonstrate a positively correlation of current signals with the intensity of sun illumination.Moreover,the superhydrophobic umbrella can be further employed to realize water rescue,which can take the underwater object onto water surface,load and rapidly transport the considerable weight.More importantly,the whole process of loaded objects and water flow velocity can be precisely detected.The self-supported smart umbrella can effectively monitor the weather and realize a smart water rescue,demonstrating significant potentials in multifunctional sensing and directional actuation in the presence of water.

关键词： Self-supported Superhydrophobic thin films Multifunctional sensing Water rescue

Complex Dynamical Behaviors in a Dual Channel Supply Chain Model with Retailer's Service Input

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Journal of Systems Science & Complexity 2023年第3期36卷 1144-1168页

作者： ZHANG Yapeng zhou wei School of Mathematics and Physics Lanzhou Jiaotong UniversityLanzhou 730070China School of Traffic and Transportation Lanzhou Jiaotong UniversityLanzhou 730070China Key Laboratory of Railway Industry of Plateau Railway Transportation Intelligent Management and Control Lanzhou 730070China

Based on bounded rationality,this paper established a price game model of dual channel supply chain composed of manufacturers and retailers.According to the eigenvalue of Jacobi matrix and Jury criterion,the stability of the equilibrium point is analyzed,and then the dynamic evolution process under the parameters of price adjustment speed and retailer's service input is studied through stability region,bifurcation diagram,maximum Lyapunov exponent diagram and attraction basin.The results show that the system enters chaos through flip and Neimark-Sacker bifurcation,and increase of price adjustment speed and service input value will make the system produce more dynamic behavior.In addition,it can be found that the impact of service input value on itself is much greater than that on manufacturers.Secondly,when adjustment speed is selected as bifurcation parameter,the change curve of sales price is inconsistent,in which the change of retailers mainly remains in periodic state,while manufacturers will gradually enter chaos.Finally,studies the evolution of attraction basin in which three kinds of attractors coexist.In particular,coexistence of boundary attractors and internal attractors increases the complexity of system.Therefore,enterprises need to carefully adjust parameters of the game model to control the stability of system and maintain the long-term stability of market competition.

关键词： Bifurcation analysis boundary equilibrium coexistence of attractors flip bifurcation global bifurcation

Abelian Subgroup Separability of Certain Generalized Free Products of Groups

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Algebra Colloquium 2020年第4期27卷 651-660页

作者： Wei Zhou Goansu Kim School of Mathematics and Statistics Southwest University Chongqing 400715China Yeungnam University Kyongsan712-749Korea

We prove that generalized free products of certain abelian subgroup separable groups are abelian subgroup separable.Applying this,we show that tree products of polycyclic-by-finite groups,amalgamating central subgroup... 详细信息

关键词： subgroup separable residually finite generalized free products tree products retracts

Ullmann-Ma Reaction:Development,Scope and Applications in Organic Synthesis

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Chinese Journal of Chemistry 2020年第8期38卷 879-893页

作者： Qian Cai Wei Zhou College of Pharmacy Jinan UniversityNo.601 Huangpu Avenue WestGuangzhouGuangdong 510632China

Copper-catalyzed cross-couplings of aryl halides and nucleophiles,traditionally called Ullmann-type coupling reactions,were initially reported by Ullmann et al.from 1901-1929.A seminal report in 1998 by Ma et al.from Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences revealed an accelerating effect caused by amino acids,which brought Ullmann-type coupling reactions into a ligand-accelerating era.From 1999 to the first 10 years of 2000s,the first-generation ligands were developed by many researchers and promoted Ullmann-type coupling reactions of aryl iodides and bromides under relatively mild conditions.Amino acid ligands,developed by Ma and coworkers,are one class of the most important first-generation ligands.In the second 10 years of 2000s,Ma et al.led the discovery of second-generation ligands for copper-catalyzed cross-coupling reactions.Two great breakthroughs have been realized by using second-generation oxalic diamide and related amide ligands,with aryl chlorides as general coupling partner and with low catalyst loadings.Now copper-catalyzed cross coupling reactions of aryl halides and nucleophiles with amino acids or oxalic diamides and related amides as ligands are recognized as Ullmann-Ma reactions and have found extensive applications in organic synthesis.

关键词： synthesis coupling Ullmann

Sodium fluoride sacrificing layer concept enables high-efficiency and stable methylammonium lead iodide perovskite solar cells

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Journal of Materials Science & Technology 2022年第18期113卷 138-146页

作者： Huimin Xiang Pengyun Liu wei Wang Ran Ran Wei Zhou Zongping Shao College of Chemical Engineering State Key Laboratory of Materials-Oriented Chemical EngineeringNanjing Tech UniversityNanjing 210009China WA School of Mines:Minerals Energy and Chemical Engineering(WASM-MECE)Curtin UniversityPerthWA 6845Australia

As next-generation photovoltaic devices,methylammonium lead iodide(MAPbI_(3))-based organic-inorganic halide perovskite solar cells(PSCs)have received considerable attention because of their cost effectiveness and high efficiency.However,their practical applications are retarded due to severe instability under moisture,thermal and sunlight conditions,which are closely related to the insufficient perovskite film quality and high photocatalytic activity of defective TiO_(2) electron-transporting layer(ETL)to accelerate the perovskite decomposition.Herein,remarkably enhanced power conversion efficiency(PCE)and stability of MAPbI_(3)-based PSCs is reached through the use of a new sodium fluoride(NaF)sacrificing layer,which,introduced between the perovskite layer and ETL,is sacrificed during cell fabrication by penetrating into the perovskite layer,improving the perovskite film quality,while partial NaF is incorporated into the mesoporous TiO_(2) ETL during NaF layer fabrication to passivate TiO_(2) and construct a well-matched energy level alignment.As a result,the optimized PSC generates a high PCE of 20.9%,which is 17%higher than that of the pristine cell(17.9%),and outstanding performance stability due to remarkably enhanced moisture,thermal and sunlight stability.This study highlights a simple and effective approach to boost the PCE and durability of MAPbI 3-based PSCs simultaneously,accelerating the commercialization of this technology.

关键词： Perovskite solar cells Sodium fluoride sacrificing layer Defect passivation Stability

Comparison of different approaches for direct coupling of solid-phase microextraction to mass spectrometry for drugs of abuse analysis in plasma

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Journal of Pharmaceutical Analysis 2023年第2期13卷 216-222页

作者： Wei Zhou Martyna N.Wieczorek Runshan Will Jiang Janusz Pawliszyn Department of Chemistry University of WaterlooWaterlooONN2L 3G1Canada Faculty of Food Science and Nutrition Poznan University of Life SciencesPoznanPoland

The direct coupling of solid-phase microextraction(SPME)to mass spectrometry(MS)(SPME-MS)has proven to be an effective method for the fast screening and quantitative analysis of compounds in complex matrices such as blood and plasma.In recent years,our lab has developed three novel SPME-MS techniques:SPME-microfluidic open interface-MS(SPME-MOI-MS),coated blade spray-MS(CBS-MS),and SPME-probe electrospray ionization-MS(SPME-PESI-MS).The fast and high-throughput nature of these SPME-MS technologies makes them attractive options for point-of-care analysis and anti-doping testing.However,all these three techniques utilize different SPME geometries and were tested with different MS instruments.Lack of comparative data makes it difficult to determine which of these methodologies is the best option for any given application.This work fills this gap by making a comprehensive comparison of these three technologies with different SPME devices including SPME fibers,CBS blades,and SPME-PESI probes and SPME-liquid chromatography-MS(SPME-LC-MS)for the analysis of drugs of abuse using the same MS instrument.Furthermore,for the first time,we developed different desorption chambers for MOI-MS for coupling with SPME fibers,CBS blades,and SPME-PESI probes,thus illustrating the universality of this approach.In total,eight analytical methods were developed,with the experimental data showing that all the SPME-based methods provided good analytical performance with R^(2)of linearities larger than 0.9925,accuracies between 81%and 118%,and good precision with an RSD%≤13%.

关键词： Solid-phase microextraction Mass spectrometry Microfluidic open interface Coated blade spray Probe electrospray ionization Drug of abuse

The impact of earlier flood recession on metacommunity diversity of wintering waterbirds at shallow lakes in the middle and lower Yangtze River floodplain

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Avian Research 2023年第2期14卷 223-230页

作者： Zhenhua wei Lizhi zhou School of Resources and Environmental Engineering Anhui UniversityHefei230601China Anhui Province Key Laboratory of Wetland Ecosystem Protection and Restoration(Anhui University) Hefei230601China Anhui Shengjin Lake Wetland Ecology National Long-term Scientific Research Base Dongzhi247230China

The hydrological regime in wetlands plays an important role in the process of wintering waterbird metacommunity assemblage.However,increasing frequency of extreme climate and the intensification of human activities,such as the construction of sluices and dams,have resulted in frequently abnormal hydrological regime in the middle and lower Yangtze River floodplain.In recent years,earlier flood recession has become one of the main hydrological problems faced in the shallow lakes,having a great impact on wetland biodiversity.It is necessary to understand the impact of earlier flood recession on waterbirds,an indicator of wetland biodiversity,and the metacommunity concept is helpful to elucidate the underlying mechanism involved in the processes of assemblage by waterbird communities.In this study,we surveyed the wintering waterbirds at three sub-lakes of Caizi Lakes during 2019-2020 and 2020-2021 and compared the richness,abundance,alpha and beta diversity of waterbirds in and among local metacommunities under earlier flood recession and normal hydrological regime.The results showed that the earlier flood recession reduced the species richness in the early stage and abundance in the late stage,it also reduced the Shannon-Wiener index in the early stage and increased the dissimilarity between and within waterbird metacommunities in the late stage.The partition of beta diversity showed that the turnover component played a major role in the process of waterbird metacommunity assemblage.It was found that the earlier flood recession reduced the richness,abundance in different stages of flood recession,which also increased the turnover of waterbirds.Metacommunities with high habitat heterogeneity had better resistance to abnormal hydrological regime,which resulted in high dissimilarity between and within metacommunities.The results of this study provide important information for waterbird conservation and water level management at shallow lakes in the middle and lower Yangtze River floodplain.

关键词： Beta diversity Flood recession Hydrological regime Metacommunity Shallow lake Waterbirds