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Single-atom Ni-N_(4) for enhanced electrochemical sensing

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Nano Research 2024年第8期17卷 7658-7664页

作者： Zhuhui Qin Bo Tang Guiru Zhang chongqing Zhu Kun Jiang Bowei Zhang Fu-Zhen Xuan Shanghai Key Laboratory of Intelligent Sensing and Detection Technology East China University of Science and TechnologyShanghai 200237China Key Laboratory of Pressure Systems and Safety of Ministry of Education East China University of Science and TechnologyShanghai 200237China School of Mechanical and Power Engineering East China University of Science and TechnologyShanghai 200237China Key Laboratory of Theoretical and Computational Photochemistry Ministry of EducationCollege of ChemistryBeijing Normal UniversityBeijing 100875China Interdisciplinary Research Center School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Single-atom catalysts(SACs)attract widespread attention in heterogeneous catalysis due to their maximum atomic utilization efficiency and unique physical and chemical ***,their applications in chemical sensing keep huge potential but remain ***,a Ni-N_(4)-C SAC was synthesized for the trace detection of dopamine(DA)and uric acid(UA).The Ni-N_(4)-C SAC exhibited superior sensing performance compared to the Ni *** detection range for DA and UA were 0.05–75μM and 5–90μM with detection limits of 0.02. and 0.82.M,*** functional theory(DFT)computations indicate that Ni-N_(4)-C has a lower reaction barrier during electrochemical process,indicating that the atomic Ni sites possess higher intrinsic activity than Ni ***,DA and UA show strong potential dependency on the Ni-N_(4)-C catalyst,indicating its applicability for their concurrent *** work extends the application of SACs in chemical sensing.

关键词： single-atom catalysts chemical sensing dopamine uric acid

Scenario simulation and forecast of land use/cover in northern china

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Chinese Science Bulletin 2008年第9期53卷 1401-1412页

作者： LI YueChen 1,2.3 & HE ChunYang 3 1 college of geographical Science,{2., chongqing 400047, china 2.college of Resources and Environmental Science, chongqing university, chongqing 400044, china 3 college of Resources Science & Technology, Beijing normal university, Beijing 100875, china college of geographical Science Chongqing Normal University Chongqing 400047 China college of Resources and Environmental Science Chongqing University Chongqing 400044 China college of Resources Science & Technology Beijing Normal University Beijing 100875 China

Modeling land use/cover scenario changes and its potential impacts on structure and functions of ecosystem in typical regions are helpful to understanding the interactive mechanism between land use/cover system and ecosystem. Based on the analysis of the existing land use/cover simulation and forecast models, a land use/cover scenario dynamics model by the integration of System Dynamics (SD) model, Back Propagation Neural Network (BPNN) and Cellular Automata (CA) model is developed with land use/cover scenario changes in northern china in the next 30 years and simulated in this paper. The model is to simulate the land use/cover scenario demands by using a SD model at first, and then allocating the land use scenario patterns at the local scale with the considerations of land use/cover suitability, inheritance ability and neighborhood effect by using BPNN-CA model to satisfy the balance between land use/cover scenario demands and supplies. It integrates the advantages of SD, BPNN and CA. Macro-driving factors and the micro-spatial pattern are also fully taken into account. The BPNN simplifies the identification of the factors’ weights used in CA model and improves the reliability of the simulation results. The simulation accuracy of the model developed in this paper was found to be about 74%. It suggests that the model has the ability to reflect the complexity of land use/cover system at different scales to some extent and it is a useful tool for assessing the potential impacts of land use system on ecosystem. The simulated results also indicate that the urban land, water area and forest will increase significantly, and farmland and unable land will decrease gradually. Obvious land use/cover changes will take place in the farming-pastoral zone and the southeast area of northern china.

关键词：土地利用中国北方细胞自动机系统动力学

Effect of annealing treatment on the structural, optical, and electrical properties of Al-doped ZnO thin films

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Rare Metals 2007年第3期26卷 247-253页

作者： LI Li FANG Liang CHEN Ximing LIU Gaobin LIU Jun YANG Fengfan FU Guangzong KONG Chunyang college of Photoelectric Engineering Chongqing University of Posts and Telecommunications Chongqing 400065 China Department of Applied Physics Chongqing University Chongqing 400044 China Department of Physics Chongqing Normal University Chongqing 400047 China

Highly conductive and transparent Al-doped ZnO （AZO） thin films were prepared from a zinc target containing Al （1.5 wt.%） by direct current （DC） and radio frequency （RF） reactive magnetron sputtering. The structural, optical, and electrical properties of AZO films as-deposited and submitted to annealing treatment （at 300 and 400℃, respectively） were characterized using various techniques. The experimental results show that the properties of AZO thin films can be further improved by annealing treatment. The crystallinity of ZnO films improves after annealing treatment. The transmittances of the AZO thin films prepared by DC and RF reactive magnetron sputtering are up to 80% and 85% in the visible region, respectively. The electrical resistivity of AZO thin films prepared by DC reactive magnetron sputtering can be as low as 8.06 x 10-4 Ωcm after annealing treatment. It was also found that AZO thin films prepared by RF reactive magnetron sputtering have better structural and optical properties than that prepared by DC reactive magnetron sputtering.

关键词： AZO thin films structure optical and electrical properties annealing transmittance spectra electrical resistivity

Polyaniline Formed in Alkaline Solution─A New Luminous Material

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Chinese Chemical Letters 2000年第8期11卷 681-684页

作者： Nian Bing LI (college of Chemistry and Chemical Engineering, Southwest china {2. university, chongqing 400715) Sheng Tao ZHANG, Pei Dao DING (college of Chemistry and Chemical Engineering, chongqing university, chongqing 400044) SW china normal Univ Coll Chem & Chem Engn Chongqing 400715 Peoples R China chongqing Univ Coll Chem & Chem Engn Chongqing 400044 Peoples R China

Electropolymerization of aniline in KOH solution and properties of the polymer are studied by using in situ reflex ellipsometry, cyclic voltammetry and fluorescence spectroscopic method. The change patterns of ellipsometric parameters and the thickness of film in the process of electropolymerization are investigated. The complex refractive indices and the fluorescence spectra of PAN indicate that the PAN is a new kind of luminous material.

关键词： Polyaniline electropolymerization alkaline solution luminous material.

Ex situ and in situ AFM investigations on the growth of the (100) face of KDP with different pH values

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Science china(Technological sciences) 2010年第6期53卷 1554-1561页

作者： CHENG Min,LI MingWei,GUO JinLi & CAO YaChao college of Power Engineering,chongqing {2.,chongqing 400030,china 1. college of Power Engineering Chongqing University Chongqing 400030 China

Through investigations on the growth of the (100) face of potassium dihydrogen phosphate (KDP) crystal by ex situ atomic force microscopy (AFM) with different pH values at different supersaturations at 40°C,it was found that the growth of crystal was controlled by step flow at lower supersaturations,and the morphologies of steps were different under different growth *** addition,at the higher supersaturations,2. nucleation mechanism controlled the *** the supersaturations were lower,the dislocation mechanism controlled the growth of crystal,and when σ≥0.05,2. nucleation mechanism played a dominant role in the growth of the (100) face for pH=4.2.and pH=***,for pH=5.0,the dislocation mechanism also dominated the growth of crystal when the supersaturations were lower,but when σ≥0.03,the crystal growth was controlled by 2. nucleation *** investigations on the step flow of the (100) face of KDP crystal by in situ AFM with different pH values at lower supersaturations at 2.°C,the velocities of normal growth of the (100) face were estimated at different growth conditions by in situ *** was found that when the pH value was 5.0,the normal growth rate was the fastest at the same supersaturation compared to the other pH values and screw dislocation mechanism controlled the crystal *** addition,we found that with the reduction of the supersaturation of the solution,the density of steps also decreased,the width of steps became ***,a phenomenon which was the obvious anisotropic growth of steps in the step flow was observed by in situ AFM at σ=0.02. at pH=5.0.

关键词： pH value KDP AFM step flow

Study of immunological activity of coarse polysaccharide of Agaricus blazei murrill

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西南师范大学学报(自然科学版) 1999年第5期24卷 594-600页

作者： Tang Wei 1,Wang Qijun 2.1 college of Physical Education,Southwest china {2. university,chongqing 400715 2.Southwest Agricultural university,chongqing 400716 西南师范大学体育学院重庆西南农业大学重庆

The coarse polysaccharide extracted from the mycelium of Agaricus blazei Murrill was served as our experimental materials. The results exhibited that it can significantly increase spleen index and phagocytic rate of macrophage and strengthen non specific immunological level of organism. It can obviously raise rosette formation percentage of active T lymphocytes(Ea%) to promote the cellular immunological level of organism. Besides, it can noticeably increase the content of haemolysin that is a circulating antibody to enhance the immunological level of body fluid. Therefore, coarse polysaccharide of A. blazei Murrill has wide applications in health care and medicine and it is a good immune strengthening agent.

关键词： Agaricus blazei Murrill polysaccharide immunological activity \

Mapping the Farming-pastoral Ecotones in china

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Journal of Mountain Science 2009年第1期6卷 78-87页

作者： ZHANG Jian WEI Jie CHEN Quangon Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Tourism college Chongqing Normal University Chongqing 400047 China School of PastoralAgricultural Science and Technology Lanzhou University Lanzhou 730020 China Graduate university of the Chinese Academy of sciences Beijing 100049 China

Conventional farming-pastoral ecotones methods of delineating were not quantitative and could not fully show their spatial distribution. The present paper attempts to develop quantitative methods for mapping farming-pastoral ecotones in china. Nine indicators, related to temperature, precipitation and altitude aspects, were selected to quantify ecological susceptibility of vegetation （crops and forage）. Methods of analytic hierarchy process （AHP） and expert score ranking combined with fuzzy set theory were applied to assign the weight for each indicator and to define the membership functions. The geographic information system （GIS） was used to manage the spatial database and conduct the spatial analysis. According to the spatial calculation of evaluation model integrated with GIS, the ecological susceptibility of vegetation （crops and forage） was mapped. Three different zones, pastoral area, farming-pastoral ecotones and farming area, were classified by spatial cluster analysis and the maximum likelihood classification for the numeric map of vegetation ecological susceptibility by GIS. This map was validated by the economic statistical result based on the ratio of the output value from animal husbandry in total output value of agriculture by the National Bureau of Statistics in china, indicating that the mapping of the farming-pastoral ecotones may be accepted.

关键词： AHP Farming-pastoral ecotone Fuzzyset theory GIS

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science china(Technological sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1 & LIU Changming1, 2.1. School of Environmental sciences, Beijing normal {2., Beijing 100875, china 2. Institute of geographic Science and Natural Resources Research, Beijing 100101, china Beijing normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1982.1998, soil moisture of all layers of soil-profile (0—1 m) in the Yellow River basin over the 17 years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1982.to 1988 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 17 years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

On the generalized Busemann-Petty problem

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Science china Mathematics 2007年第8期50卷 1103-1116页

作者： Song-jun L~(1,2.) Gang-song LENG~1 1.college of Mathematics and Computer Science,chongqing {2. university,Chongqin 400047,china 2.Department of Mathematics,Shanghai university,Shanghai 2.0444,china college of Mathematics Computer Science Chongqing Normal University Chongqin 400047 China Department of Mathematics Shanghai University Shanghai 200444 China

The generalized Busemann-Petty problem asks whether the origin-symmetric convex bodies in ? n with a larger volume of all i-dimensional sections necessarily have a larger volume. As proved by Bourgain and Zhang, the answer to this question is negative if i > 3. The problem is still open for i = 2. 3. In this article we prove two specific affirmative answers to the generalized Busemann-Petty problem if the body with a smaller i-dimensional volume belongs to given classes. Our results generalize Zhang’s specific affirmative answer to the generalized Busemann-Petty problem.

关键词： star body cross i-section dual mixed volume Radon transform 52.30 52.40