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Structural Transition from Ordered to Disordered of BeZnO2 Alloy

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Chinese Physics Letters 2020年第5期37卷 81-84页

作者： Li-Xia Qin Han-pu Liang Rong-Li jiang School of Materials and Physics China University of Mining and TechnologyXuzhou 221116 School of Chemical Engineering China University of Mining and TechnologyXuzhou 221116

Employing Monte Carlo simulations based on the cluster expansion,the special quasi-random structures and first-principles calculations,we systematically investigate the structure transition of BeZnO2 alloys from the ordered to the disordered phase driven by the increased synthesis temperature,together with the solid-state phase *** is found that by controlling the ordering parameter at the mixed sublattice,the band structure can vary continuously from a wide direct band gap of 4.61 eV for the fully ordered structure to a relatively narrow direct band gap of 3.60 eV for the fully disordered ***,a better optical performance could be achieved simply by controlling the synthesis temperature,which determines the ordering parameters and thus the band gaps.

关键词： structure. BeZnO ordered

Occurrence and distribution of hexabromocyclododecane in sediments from seven major river drainage basins in China

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Journal of Environmental Sciences 2013年第1期25卷 69-76页

作者： Honghua Li Hongtao Shang pu Wang Yawei Wang Haidong Zhang Qinghua Zhang Guibin jiang State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of Sciences

The concentrations and geographical distribution of hexabromocyclododecane （HBCD） were investigated in 37 composite surface sediments from seven major river drainage basins in China, including Yangtze River, Yellow River, Pearl River, Liaohe River, Haihe River, Tarim River and Ertix River. The detection frequency of HBCD was 54%, with the concentrations ranged from below limit of detection （LOD） to 206 ng/g dry weight. In general, the geographical distribution showed increasing trends from the upper reaches to the lower reaches of the rivers and from North China to Southeast China. Compared to other regions in the world, the average concentration of HBCD in sediments from Yangtze River drainage basin was at relatively high level, whereas those from other six river drainage basins were at lower or similar level. The highest HBCD concentration in sediment from Yangtze River Delta and the highest detection frequency of t-IBCD in Pearl River drainage basins suggested that the industrial and urban activities could evidently affect the HBCD distribution. HBCD diastereoisomer profiles showed that y-HBCD dominated in most of the sediment samples, followed by ct- and [3-HBCD, which was consistent with those in the commercial HBCD mixtures. Further risk assessment reflected that the average inventories of HBCD were 18.3, 5.87, 3.92, 2.50, 1.77 ng/cm2 in sediments from Pearl River, Haihe River, Tarim River, Yellow River and Yangtze River, respectively.

关键词： HBCD surface sediment Chinese river drainage basin distribution

A Robust N-Terminal Pro-Brain Natriuretic Peptide Assay for Clinical Diagnosis of Heart Failure in Elderly Patients

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Journal of Analysis and Testing 2024年第1期8卷 74-82页

作者： Xue Gong jiangling Wu Jiajia Zhang Zhongwei jiang Yi Wang pu Zhang Engineering Research Center for Biotechnology of Active Substances(Ministry of Education) Chongqing Key Laboratory of Green Synthesis and ApplicationsCollege of ChemistryChongqing Normal UniversityChongqing 401331China Chongqing Research Center for Pharmaceutical Engineering College of PharmacyChongqing Medical UniversityChongqing 400016China Department of Clinical Laboratory University Town Hospital of Chongqing Medical UniversityChongqing 401331China

Heart failure(HF)is a clinical hallmark of cardiovascular syndrome leading to substantial morbidity,repeated hospitalization,and enormous healthcare *** elderly populations continue to increase,biomarker-guided diagnosis and treatment for age-related cardiac decline have become *** evidence demonstrates that N-terminal proBNP(NT-proBNP)can provide a unique window into the diagnosis and risk stratification with ***,a simple yet robust aptasensor is developed for on-site recognizing the NT-proBNP by its targeting aptamer,thus achieving the accurate diagnosis of *** aptasensing system is prepared by absorbing the fluorophore-labeled aptamer strand onto the graphene oxide(GO),leading to efficient quenching without possible off-site signal *** aptamer strand can specifically identify target NT-proBNP molecules via a versatile conformational transformation,resulting in the desorption of the aptamer-NTproBNP complexes from GO and re-generation fluorescence signal,thus allowing sensitive detection of NT-proBNP in 37 clinical blood *** advantage of the high specificity of aptamer-guaranteed recognitions of NT-proBNP,this aptasensor system readily achieves better diagnostic performance for HF than commercially adopted chemiluminescence immunoassay(Siemens,CLIA)in hospitals in terms of accuracy(89.2%vs 83.8%),specificity(89.5%vs 84.2%),and positive predictive value(88.9%vs 83.3%).This work provides a stable option for the diagnosis and treatment of elderly HF-related diseases inclinics.

关键词： NT-proBNP Graphene oxide Aptamer Heart failure Clinical diagnosis

First total synthesis of eudistalbin A

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Chinese Chemical Letters 2010年第8期21卷 889-891页

作者： pu Yong Zhang Jun Lei Wang Sheng Biao Wan Tao jiang School of Medicine and Pharmacy Key Laboratory of Marine DrugsMinistry of Education Ocean University of ChinaQingdao 266003China

Eudistalbin A was isolated from marine tunicate eudistoma album and possess cytotoxic activity（ED_（50）3.2μg/mL） in vitro against the growth of KB human buccal carinoma *** synthetic eudistalbin A showed potent inhibitory activity against the breast carcinoma cell line MDA-231 with an IC_（50） value of 2.1μmol/L using the metabolic assay *** structures of new compounds were confirmed by ~1H NMR,^（13）C NMR,HRMS and optical rotation.

关键词： β-Carboline Eudistalbin A Pictet-Spengler reaction Henry reaction Total synthesis

Facile surface regulation for highly efficient and thermally stable perovskite solar cells via chlormequat chloride

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Chinese Chemical Letters 2024年第10期35卷 517-523页

作者： Bo Yang pu-An Lin Tingwei Zhou Xiaojia Zheng Bing Cai wen-Hua Zhang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China School of Physical Science and Technology Southwest UniversityChongqing 400715China Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies School of Materials and EnergyYunnan UniversityKunming 650000China

Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells(PSCs).Herein,a simple and stable quaternary ammonium halide,named chlormequat chloride(i.e.,chlorinated choline chloride,CCC),is introduced to regulate the upper surface chemical environment of perovskite *** anion(Cl^(-))and cation[ClCH_(2)CH_(2)N(CH_(3))_(3)]+in CCC could effectively self-search and passivate positively and negatively charged ionic defects in per ovskites,respectively,which contributes to inhibited nonradiative recombination and reduced energy los in *** a result,the champion power conversion efficiency(PCE)of PSCs can be significantly enhanced from 22.82%to 24.07%.Moreover,the unencapsulated device with CCC modification retains 92.0%of it original PCE even subject to thermal aging at 85℃ for 2496 *** work provides guidance for the ratio nal design of functional molecules as defect passivators in PSCs,which is beneficial for the improvement in both device performance and stability.

关键词： Perovskite solarcells Quaternary ammonium halide Chlormequat chloride Surface modulation Thermal stability

Tri-level programming model for combined urban traffic signal control and traffic flow guidance

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Journal of Central South University 2016年第9期23卷 2443-2452页

作者： SUN Zhi-yuan LU Hua-pu QU wen-cong Institute of Transportation Engineering Tsinghua University Beijing 100084 China College of Metropolitan Transportation Beijing University of Technology Beijing 100124 China

In order to balance the temporal-spatial distribution of urban traffic flow, a model is established for combined urban traffic signal control and traffic flow guidance. With consideration of the wide use of fixed signal control at intersections, traffic assignment under traffic flow guidance, and dynamic characteristics of urban traffic management, a tri-level programming model is presented. To reflect the impact of intersection delay on traffic assignment, the lower level model is set as a modified user equilibrium model. The middle level model, which contains several definitional constraints for different phase modes, is built for the traffic signal control optimization. To solve the problem of tide lane management, the upper level model is built up based on nonlinear 0-1 integer programming. A heuristic iterative optimization algorithm(HIOA) is set up to solve the tri-level programming model. The lower level model is solved by method of successive averages(MSA), the middle level model is solved by non-dominated sorting genetic algorithm II(NSGA II), and the upper level model is solved by genetic algorithm(GA). A case study is raised to show the efficiency and applicability of the proposed modelling and computing method.

关键词： traffic engineering traffic signal control traffic flow guidance tri-level programming model

Hot Dust Acoustic Solitary Waves in Dust Plasma with Variable Dust Charge

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Chinese Physics Letters 2001年第8期18卷 1088-1089页

作者： DUAN wen-Shan LÜ Ke-pu ZHAO Jin-Bao Department of Physics Northwest Normal UniversityLanzhou 730070

Considering the variation of dust charges,We have analytically studied the governing equation for the system with the same model as that for cold dust acoustic waves in a demagnetized plasma but the contribution of hot *** result indicates that the governing equation is also a Korteweg-de Vries equaiton,although its amplitude and width will be smaller compared with the cold dust case.

关键词： equation governing charges

应用谷歌地球引擎和多维特征集构建的艾比湖流域长时序景观分类模型

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东北林业大学学报 2025年第2期53卷 97-104页

作者：雷焯越蒲智周军新疆农业大学乌鲁木齐830000

以新疆艾比湖流域为研究区域,整合历史遥感影像数据与现场地表特征考察,将艾比湖流域景观类型划分为6类(耕地、林地、草地、水域、建设用地、未利用地);以谷歌地球引擎(GEE)平台提供的艾比湖流域2002—2023年(2002、2008、2013、2018、2... 详细信息

以新疆艾比湖流域为研究区域,整合历史遥感影像数据与现场地表特征考察,将艾比湖流域景观类型划分为6类(耕地、林地、草地、水域、建设用地、未利用地);以谷歌地球引擎(GEE)平台提供的艾比湖流域2002—2023年(2002、2008、2013、2018、2023年)的陆地卫星(Landsat)影像为基础数据源,以艾比湖流域长时序景观分类为评价指标,光谱指数(归一化植被指数、增强植被指数、归一化水体指数、归一化建筑指数)、地形特征(海拔、坡度、坡向)、纹理特征(角二阶矩阵、对比度、相关性、熵、协方差、逆方差、总和平均值)为影响因素,从光谱指数、地形特征、纹理特征三个角度构建并筛选最优多维特征模型;分别运用分类回归树(CART)、随机森林(RF)、梯度提升树(GBT)、支持向量机(SVM)机器学习算法,对艾比湖流域长时序景观信息进行自动分类,对比4种机器学习算法的分类精度,遴选最适用于艾比湖流域的景观分类模型。结果表明:(1)应用谷歌地球引擎云计算平台,能够高效处理、分析及可视化研究区近22 a的景观分类结果。(2)3类特征重要性,由大到小依次为光谱指数(31.52%)、地形特征(17.18%)、纹理特征(3.83%)。地形特征在单一特征中分类精度最高;光谱特征联合纹理特征,在双特征配置中对提高研究区景观分类精度呈现出较好效果;而整合光谱指数、地形特征、纹理特征的模型,能够在任一特征组合的基础上有效提高研究区景观分类模型精度。(3)4种分类算法融合光谱、地形、纹理特征,分类精度由高到低依次为随机森林、梯度提升树、分类回归树、支持向量机;随机森林在5期(2002、2008、2013、2018、2023年)影像中的总体分类精度不低于93%,卡帕系数(Kappa)不低于0.92,最适用于艾比湖流域景观分类。

关键词：景观分类生态系统生态环境艾比湖流域

Enhanced photoluminescence and stability of ZnSe microspheres/Cs4PbBr6 microcrystals/CsPbBr3 nanocrystals composites

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Chinese Chemical Letters 2020年第9期31卷 2499-2502页

作者： Chao Zhang Tingting Li Lei pu Weijia wen Xiangdong Luo Lijuan Zhao Materials Genome Institute Shanghai UniversityShanghai 200444China jiangsu Key Laboratory of ASIC Design Nantong UniversityNantong 226019China State Key Laboratory of Transducer Technology Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050China

A ternary complex combining dual-phase perovskites-Cs4PbBr6/CsPbBr3(DP-CPB) with ZnSe micropshere s(ZnSe-DP-CPB) was succes s fully prepared using supersaturated recrystallization technique at room *** was showed that the DP-CPB composites were partially embedded in ZnSe microsphere composed with ZnSe *** light absorption range of ZnSe-DP-CPB composites was extended from visible to near infrared *** enhanced luminescence from ZnSe-DP-CPB composite was observed and the excitation power-dependent photoluminescence showed that the recombination involves *** recombination lifetimes of the ternary composites increased compared with DP-CPB composite,indicating that the non-radiative combination was suppressed which maybe possibly due to the decrease of both bulk and surface defects,owing to the passivation of ZnSe,as well as the suitable band alignments of these three *** ternary complex also showed improved stability of photoluminescence(PL),which opens a newavenue for enhancing the stability of PL and optoelectronic applications for semiconductor-perovskite composites.

关键词： Dual-phase perovskites Ternary complex Supersaturated recrystallization Photoluminescence Passivation Optoelectronic