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Attribution analysis and multi-scenario prediction of NDVI drivers in the Xilin Gol grassland,China

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Journal of Arid Land 2022年第9期14卷 941-961页

作者： XU Mengran ZHANG Jing LI Zhenghai mo yu College of Enoironment and Bioresources Dalian Minzu UniversityDalian 116600China

Grassland degradation is influenced by climate change and human activities,and has become a major obstacle for the development of arid and semi-arid areas,posing a series of environmental and socio-economic *** in-depth understanding of the inner relations among grassland vegetation dynamics,climate change,and human activities is therefore greatly significant for understanding the variation in regional environmental conditions and predicting future developmental *** on moDIS(moderate resolution imaging spectroradiometer)NDVI(normalized difference vegetation index)data from 2000 to 2020,our objective is to investigate the spatiotemporal changes of NDVI in the Xilin Gol grassland,Inner mongolia Autonomous Region,*** with 12 natural factors and human activity factors in the same period,the dominant driving factors and their interactions were identified by using the geographic detector model,and multiple scenarios were also simulated to forecast the possible paths of future NDVI changes in this *** results showed that:(1)in the past 21 a,vegetation cover in the Xilin Gol grassland exhibited an overall increasing trend,and the vegetation restoration(84.53%)area surpassed vegetation degradation area(7.43%);(2)precipitation,wind velocity,and livestock number were the dominant factors affecting NDVI(the explanatory power of these factors exceeded 0.4).The interaction between average annual wind velocity and average annual precipitation,and between average annual precipitation and livestock number greatly affected NDVI changes(the explanatory power of these factors exceeded 0.7).moreover,the impact of climate change on NDVI was more significant than human activities;and(3)scenario analysis indicated that NDVI in the Xinlin Gol grassland increased under the scenarios of reduced wind velocity,increased precipitation,and ecological *** contrast,vegetation coverage restoration in this area was significantly reduced under the scenarios o

关键词： normalized difference vegetation index(NDVI) grassland degradation geographical detector Cellular Automat(CA)–Markov model Xilin Gol grassland

RELATIONSHIP OF FIRST STEP HEIGHT,STEP SLOPE AND CAVITY IN X-SHAPED FLARING GATE PIERS

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Journal of Hydrodynamics 2007年第3期19卷 349-355页

作者： WANG Bo WU Chao HU Yao-hua mo Zheng-yu State Key Laboratory of Hydraulics and mountain River Engineering Sichuan University Chengdu 610065 China.

The energy dissipation of X-shaped flaring gate piers ahead of a stepped spillway was adopted in the Suofengying Hydroplant. Under the circumstance that the first step is higher than others, at the step surface an aerated cavity occured behind piers. The interaction of the weir head, the elevation difference between crest and chamber outlet, the first step height, the slopes of weir end and step, and the size of cavity, was investigated, the expression was derived to characterize their relationship, and the corresponding curves were plotted. The comparison of the calculated and simulated results with the measured data was performed. When the slopes of step and weir end are equivalent, the relative height difference between the first and second steps becomes the main factor influencing the aerated cavity. These findings may be useful in practical applications.

关键词： X-shaped flaring gate pier first step height slope of weir end step slope size of cavity

Uniform design ray in the assessment of combined toxicities of multi-component mixtures

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Science Bulletin 2016年第1期61卷 52-58页

作者： Shu-Shen Liu Qian-Fen Xiao Jin Zhang mo yu Key Laboratory of Yangtze River Water Environment Ministry of Education College of Environmental Science and Engineering Tongji University College of Environment and Energy Engineering Anhui Jianzhu University

Multi-component mixture(MCM) is a complicated chemical system that contains a great deal of mixture rays with various mixture ratios, and each ray includes many mixtures with different concentration ***, in combined toxicity field, almost all studies on MCM focus on the mixtures designed by the equivalenteffect concentration ratio(EECR) procedure. However, the EECR mixtures cannot represent the whole mixture system because the EECR mixtures are located on one mixture ray in concentration space formed by multiple components. In our view, some optimal experimental design such as the uniform design(UD) should be used to effectively select many representative mixture rays from the MCM system,instead of single EECR ray. The uniform design ray(UDray) integrating UD idea with fixed-ratio ray design can systematically and comprehensively measure the combined toxicity changes in the MCM system. This review introduces the operation method, construction of uniform table and corresponding usable table, and some cases of application of the UD-ray to help readers easily use UD-ray in their MCM toxicity assessment.

关键词： Chemical mixture Uniform design Ray design Mixture ratio. Concentration-responserelationship Toxicity interaction

Mass spectrometry-based proteomic approaches to study pathogenic bacteria-host interactions

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Protein & Cell 2015年第4期6卷 265-274页

作者： yufei Yang mo Hu Kaiwen yu Xiangmei Zeng Xiaoyun Liu Institute of Analytical Chemistry and Synthetic and Functional Biomolecules Center College of Chemistry and MolecularEnclineerinq Pekinq University Beijing 100871 China

Elucidation of molecular mechanisms underlying host- pathogen interactions is important for control and treatment of infectious diseases worldwide. Within the last decade, mass spectrometry （MS）-based proteomics has become a powerful and effective approach to better understand complex and dynamic host-pathogen inter- actions at the protein level. Herein we will review the recent progress in proteomic analyses towards bacterial infection of their mammalian host with a particular focus on enteric pathogens. Large-scale studies of dynamic proteomic alterations during infection will be discussed from the perspective of both pathogenic bacteria and host cells.

关键词： mass spectrometry proteomics bacterial infection host-pathogen interactions

Mixture Toxicities of Three Pesticides Having Different Time-Toxicity Profiles

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Chinese Journal of Chemistry 2014年第6期32卷 545-552页

作者： mo yu Shushen Liu Mengchao Wang Fu Chen Hanxiao Tang Key Laboratory of Yangtze River Water Environment Ministry of EducationCollege of Environmental Science and EngineeringTongji UniversityShanghai 200092China

In the environment,chemical pollutants always exist as *** evaluate mixture toxicity,we should ex-amine the concentration ratios and the concentration levels of mixture components as well as the interactive time between the components and testing *** three pesticides,metribuzin(MET),dodine(DOD)and ri-domil(RID),as mixture components,Vibrio qinghaiensis sp.-Q67 as testing organism,and 96-well microplate as exposure experiment carrier,the luminescence inhibition toxicities of the pesticides and their binary mixtures at six exposure time points(0.25,2,4,8,12,and 16 h)were *** results showed that the three pesticides have different time-toxicity *** toxicity of MET increases over time,and those of DOD and RID show a slight decrease or increase in the first 4 h,respectively,and then remain unchanged to 16 *** toxicities of the binary mixtures consisting of the three pesticides depend on not only the mixture composition but also the exposure *** time-toxicity profiles of all rays in MET-DOD mixture system are U-shaped curves,those in MET-RID system are basically monotonically increased and those in DOD-RID system are basically monotonically ***-ever,our findings indicate that for the test substances,mixture toxicity can be predicted by the extended concentra-tion addition model.

关键词： mixture toxicity concentration addition direct equipartition ray design pesticide time-toxicity profile

A Device for Simulating Soil Nutrient Extraction and Plant Uptake

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Pedosphere 2012年第6期22卷 755-763页

作者： YANG Xu-Jian LAI Yong-Lin mo Jin-yu SHEN Hong Laboratory of Root Layer Control College of Natural Resources and EnvironmentSouth China Agricultural UniversityGuangzhou 510642(China)

In situ evaluating the availability of soil nutrients has been a challenge. In this study, a new type of Device for Simulating Soil Nutrient Extraction and Plant Uptake （DSSNEPU） and its operating procedures were introduced. The device consists of a sampling tube, a fluid supply system, a low pressure system, a tube sheath and an elution cylinder. The sampling tube was firstly soaked in the solution of 0.5 mol L-1 NaHCO3 and then buried into soils. The fluid supply system was connected to the sampling tube and the deionized water was supplied. During the period, low pressure system started a vacuum for 3 min every 10 rain interval. After extraction, the sampling tube was removed and the nutrients on the sampling tube were eluted with 0.5 tool L-1 HCl. The elution solution was used for nutrient measurement. The amounts of P and K extracted by DSSNEPU reached the maximal values after 4 h. No significant increases of P and K were observed for longer extraction duration. The optimal temperature for extracting P and K was 30 ℃ in this experiment. Extracted P and K were increased by 83.3% and 84.6% with the employment of low pressure system in comparison to those without employing low pressure system. Correlation analysis indicated that 1~ and K extracted by DSSNEPU were highly correlated with those by conventional chemical extraction and by plant uptake. The above results suggest that this device is applicable to assess the availability of nutrients in soils.

关键词： available nutrients conventional chemical extraction ion exchange membrane low pressure system soil nutrient evaluation

Green revolution in electronic displays expected to ease energy and health crises

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Light(Science & Applications) 2021年第3期10卷 327-340页

作者： yuyang Wang Hui Nie Jinsong Han Yaxun An yu-mo Zhang Sean Xiao-An Zhang State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Department of Chemistry and Biochemistry University of CaliforniaSanta BarbaraSanta BarbaraCalifornia 93106USA State Grid Heilongjiang Electric Power Co. LtdHeihe Power Supply CompanyHeihe 164300China Jiaxing IrS Display Technology Co. LtdJiashan 314113China

The technological revolution of long-awaited energy-saving and vision-friendly displays represented by bistable display technology is *** we discuss methods,challenges,and opportunities for implementing bistable displays in terms of molecular design,device structure,further expansion,and required criteria,hopefully benefiting the light-related community.

关键词： energy electronic revolution

Microstructure evolution and diffusion mechanism of Nb/TiAl alloy diffusion-bonded joints

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Rare Metals 2023年第5期42卷 1686-1694页

作者： Kun Huang Hong-Liang Sun Ze-Wen Huang mo-yu Liao Yang Li School of Materials Science and Engineering Southwest Jiaotong UniversityChengdu610031China Key Laboratory of Advanced Technologies of Materials Ministry of EducationChengdu610031China

The interdiffusion behavior in Nb/TiAl alloy diffusion couples was *** process was carried out in the temperature range of 950-1400℃for 8 h in the vacuum hot-pressure sintering *** microstructural evolution was observed by optical microscopy(OM),electron backscattered diffraction(EBSD),X-ray diffraction(XRD)technique and transmission electron microscopy(TEM).The element concentration distribution at the bonded interface was obtained by scanning electron microscopy with an energy-dispersive X-ray spectroscopy(EDS)*** thickness of reaction interface increases with bonding temperature *** formed phases in diffusion interface are found to be O-Ti_(2)AlNb,σ-Nb_(2)Al,δ-Nb_(3)Al and Nb solid solution(Nbss)at 1350℃.The average interdiffusion coefficient of the interface elements was calculated by the theory of *** results indicate that Al diffuses faster than Nb and Nb diffuses faster than Ti in the Ti-Al-Nb ***,it is found that Ti promotes the diffusion of Al and Nb and Nb inhibits the diffusion of Ti and Al in the process of diffusion.

关键词： Diffusion bonding TiAl alloys Nb Interface microstructure Interdiffusion coefficient

Solitonic Diffusion of Wavepackets in One-Dimensional Bose–Einstein Condensates

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Chinese Physics Letters 2019年第12期36卷 1-4页

作者： yu mo Cong Zhang Shiping Feng Shi-Jie Yang Department of Physics Beijing Normal UniversityBeijing 100875

Solitonic characteristics are revealed in the diffusion process of a hump or a notch wave packet in a one-dimensional Bose-Einstein *** numerically solving the time-dependent Gross-Pitaevskii equation,we find completely different spreading behavior for attractive or repulsive *** the attractive condensate,a series of bright solitons are continuously generated one after another at the wave front and they nearly stay at the positions where they are generated in the whole diffusion *** contrast,for the repulsive condensate,the initial wave packet splits at the beginning into a series of grey solitons that travel at different *** moving velocity of the grey soliton depends on nonlinear interaction strength,as well as the shape of a particular grey soliton.

关键词： process Einstein attractive