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Geochemical Characteristics and Occurrence States of RE Element in Phosphorite in Xinhua , Zhijin, Guizhou

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Journal of Rare Earths 2004年第z1期22卷 320-324页

作者： Zhang Jie Zhang Qin Chen Dailiang cheng Jiyan zhu Lei chengdu University of Technology Geosciences College Chengdu 610059 China Guizhou University College of Resources and Environment Guiyang 550003 China Guizhou University College of Resources and Environment Guiyang 550003 China GuiZhou Geological Survey Academy Ministry of Chemical Industry Zunyi 563100 China Guizhou University College of Resources and Environment Guiyang 550003 China Guizhou University College of Resources and Environment Guiyang 550003 China

The RE and composition of trace elements analysis show that phosphorite-ores are rich in ∑ RE concentration generally in Xinhua, *** phosphorites were measured to gather LRE and HRE *** is higher than other *** phosphorite has enriched Y, La and Nd chemical *** are leading characteristics of concentrated La, LRE and Y, *** chondrite-normalized RE element patterns of the Xinhua dolomitic phosphorite distribute mode for rightwards type to one side of the ***/HRE ＞ 1, (La/Sm)N ＞ (Gd/Yb)N, and all indicate that LRE content is higher than *** test mode of chemical analysis of single mineral, chemistry phase analysis, scan electric analysis and micro-electronics probe analysis were *** chart of EDAX showed that there was representative element-Y(RE) in *** was no independent mineral of the *** is show that part of the few rare earth chemical element is adsorbed by the clay mineral, much for the type of quality isomorphic form exist in the apatite crystal structure of phosphorite inside.

关键词： occurrence of RE phosphorites in Xinhua rare earths

Ob ject Tracking with Dual Field-of-view Switching in Aerial Videos

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International Journal of Automation and computing 2016年第6期13卷 565-573页

作者： Yi Song Shu-Xiao Li cheng-Fei zhu Hong-Xing Chang The Integrated Information System Research Center Institute of AutomationChinese Academy of Science

Visual object tracking plays an important role in intelligent aerial surveillance by unmanned aerial vehicles（UAV）. In ordinary applications, aerial videos are captured by cameras with a fixed-focus lens or a zoom lens, for which the field-of-view（FOV）of the camera is fixed or smoothly changed. In this paper, a special application of the visual tracking in aerial videos captured by the dual FOV camera is introduced, which is different from ordinary applications since the camera quickly switches its FOV during the capturing. Firstly, the tracking process with the dual FOV camera is analyzed, and a conclusion is made that the critical part for the whole process depends on the accurate tracking of the target at the moment of FOV switching. Then, a cascade mean shift tracker is proposed to deal with the target tracking under FOV switching. The tracker utilizes kernels with multiple bandwidths to execute mean shift locating, which is able to deal with the abrupt motion of the target caused by FOV switching. The target is represented by the background weighted histogram to make it well distinguished from the background, and a modification is made to the weight value in the mean shift process to accelerate the convergence of the tracker. Experimental results show that our tracker presents a good performance on both accuracy and efficiency for the tracking. To the best of our knowledge, this paper is the first attempt to apply a visual object tracking method to the situation where the FOV of the camera switches in aerial videos.

关键词： tracker camera histogram captured surveillance switching intelligent cascade Tracking quickly

Preparation and characterization of Cu2ZnSn(S,Se)4 film by drop-coating of Cu2ZnSnS4 nanoink

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Rare Metals 2016年第9期35卷 718-722页

作者： Xiao-Gong Lv Jing-Yu Wang cheng-Jun zhu Zhi-Ping Wang Key Laboratory of Semiconductor Photovoltaic Technology of Inner Mongolia Autonomous Region School of Physical Science and TechnologyInner Mongolia UniversityHohhot 010021China Ordos Institute of Technology Ordos 017000China

In this work,a simple and facile one-pot oleylamine solvothermal synthetic method was developed to synthesize Cu2ZnSnS4（CZTS） *** the Cu2ZnSn（S,Se）4（CZTSSe） thin films were prepared by selenizing CZTS *** obtained CZTS nanocrystals and CZTSSe films were studied using X-ray diffraction（XRD）,transmission electron microscopy（TEM）,scanning electron microscopy（SEM）,energy-dispersive X-ray spectroscopy（EDX）,and ultraviolet–visible spectrophotometer（UV–Vis）.TEM results show that the sphere–like CZTS nanoparticles with diameter between 12 and 35 nm are *** studies indicate that the prepared CZTS nanocrystals form kesterite crystal structure,and the CZTSSe films with kesterite crystal structure are also obtained at the annealing temperatures of 500 and550 °*** particular after annealing at 500 °C for 20 min,the CZTSSe film exhibits a smooth,uniform,crack-free,and large-grained topography and possesses Cu-poor and Sn-rich ***,it shows strong optical absorption from visible to near-infrared（IR） region,and its optical band gap（Eg） is found to be about 1.44 e V.

关键词： Thin films Oleylamine solvothermal Crystal structure CZTS nanocrystals

Isatindigodiphindoside,an alkaloid glycoside with a new diphenylpropylindole skeleton from the root of Isatis indigotica

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Chinese Chemical Letters 2018年第1期29卷 119-122页

作者： Ling-Jie Meng Qing-Lan Guo cheng-Gen zhu cheng-Bo Xu Jian-Gong Shi State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Chinese Academy of Medical Sdences and Peking Union Medical College Belting 100050 China

A novel indole alkaloid glycoside with an unprecedented 2-（diphenylpropyl）indole skeleton, isatindigodiphindoside （1）, was isolated from an aqueous extract of the roots of lsatis indigotica. The structure was determined by extensive spectroscopic studies, especially by 2D NMR data analysis combined with enzymatic hydrolysis and ECD calculations. Plausible biosynthetic pathways of compound 1 are also discussed.

关键词： CruciferaeIsatis indigoticaBan lan genDiphenylpropylindoleAlkaloid glycosidelsatindigodiphindoside

Design and simulation of electrical dynamometer using improved DTC induction motor driver

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Journal of Central South University 2017年第6期24卷 1360-1368页

作者： zhu cheng-li WANG Yan-zhong HOU Liang-wei School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China

AC motors, especially the squirrel cage induction motors have the advantages of simple structure, good reliability and low cost. They are more suitable to be used as electrical dynamometers to provide dynamic load for bench test systems. But, the speed and torque of induction motors are not easy to be controlled accurately. In this work, an electrical dynamometer based on the induction motor is proposed. In order to get better control performance of torque and speed of induction motor, an improved direct torque control method(DTC) is also developed based on the space vector modulation(SVM) technique. The performance of the proposed dynamometer system is validated in the Matlab/Simulink platform. The simulation results show that the new dynamometer has good torque and stator flux response. And the torque and stator current ripples of it are reduced significantly compared with using the conventional DTC method.

关键词： dynamometer induction motor direct torque control (DTC) direct torque control method-space vector modulation DTC-SVM PI controller

Microbial PAH-Degradation in Soil: Degradation Pathways and Contributing Factors

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Pedosphere 2006年第5期16卷 555-565页

作者： ZHANG Xu-Xiang cheng Shu-Pei zhu cheng-Jun SUN Shi-Lei State Key Laboratory of Pollution Control and Resource Reuse of China Department of Environmental Sciences Nanjing University Nanjing 210093 （China）

Adverse effects on the environment and high persistence in the microbial degradation and environmental fate of polycyclic aromatic hydrocarbons (PAHs) are motivating interest. Many soil microorganisms can degrade PAHs and use various metabolic pathways to do so. However, both the physio-chemical characteristics of compounds as well as the physical, chemical, and biological properties of soils can drastically influence the degradation capacity of naturally occurring microorganisms for field bioremediation. Modern biological techniques have been widely used to promote the efficiency of microbial PAH-degradation and make the biodegradation metabolic pathways more clear. In this review microbial degradation of PAHs in soil is discussed, with emphasis placed on the main degradation pathways and the environmental factors affecting biodegradation.

关键词： bioremediation microbial degradation PAHs soil

Experimental investigation of regular wave propagation over an idealized reef model

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Journal of Hydrodynamics 2020年第4期32卷 717-726页

作者： Gan-cheng zhu Bing Ren Hong-jie Wen Guo-yu Wang Yong-xue Wang State Key Laboratory of Coastal and Offshore Engineering Dalian University of TechnologyDalian 116024China

The wave transformation over the deep-sea coral reefs is an essential issue in the analysis of the reef ecosystem and the design of large reef-top *** wave flume experiments are conducted to investigate the wave transformation processes over an idealized reef *** measurements of the wave height,the wave set-up and the wave-generated flow on the reef-top are made with and without the reef-top structure at various submerged depths and under different wave *** is found that the reef-top structure has a significant influence on the wave breaking,the wave set-up and the wave-generated *** wave set-up increases with the increasing wave height and the decreasing submergence ***,the relationship between the wave set-up and the wave period is complex,influenced by the reef-top structure.

关键词： Coral reef wave set-up reef-top structure wave breaking wave-generated flow

Impact of Holocene environmental change on temporal-spatial distribution of Neolithic sites in Huaihe River Basin, Anhui Province

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Journal of Geographical Sciences 2006年第2期16卷 199-208页

作者： HUANG Run zhu cheng GUAN Yong ZHENG Chaogui Department of Urban and Resources Sciences Nanjing University Nanjing 210093 China Department of Urban Construction and Environmental Science Wanxi College Lu＇an 237012 China

The Huaihe River basin of Anhui is not only a transitional zone of physical geography, but also a convergent area of many cultures in China. It is one of the sensitive ecotones to global changes and the birthplace of Chinese civilization. Using the field archaeological data and the sporo-pollens and the age data of the drilling cores, we analysed Neolithic cultural development and environmental evolution in the Huaihe River basin of Anhui. According to the combination of some research results in archaeology with environmental evolution research, this paper discusses the relationship between culture and environment in the Huaihe River basin of Anhui. The Neolithic cultural development was strongly impacted by the environmental change. The primitive culture （Shishanzi） was developed in the beginning of the Holocene Megathermal Period with distinct regional feature of the culture. From 6.5 kaBP to 5.5 kaBP, the climate changed warmer and wetter. The frequent occurrence of flood and waterlog due to such a climate regime and high sea level caused the earth＇s surface environment deteriorated in the Huaihe River basin of Anhui and the interruption of the Neolithic cultural development, hence a lack of archaeological sites. From 5.5 kaBP to 4.0 kaBP, the climate changed from wet to dry, the natural environment was propitious to human survival. Dawenkou Culture and Longshan Culture flourished in this period. The Neolithic cultural development, the number of the sites and their distribution characteristics of the sites in the study area differed apparently from those in Central China and Shandong Province.

关键词： Holocene environmental change Neolithic site temporal-spatial distribution Huaihe Riverbasin of Anhui

财政金融协同支持新型农村集体经济发展机理与路径优化研究

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农业展望 2024年第5期20卷 10-16页

作者：魏昊张瑞涛王兴华程竹山西农业大学农业经济管理学院山西太原030801 河北省社会科学院河北石家庄050000

发展新型农村集体经济,当务之急、重中之重就是要构建财政金融协同支持新型农村集体经济的政策体系。本研究分析财政金融协同支持新型农村集体经济的内在机理,基于成都“农贷通”和浙江“千万工程”典型性案例,探究财政协同支持集体经... 详细信息

发展新型农村集体经济,当务之急、重中之重就是要构建财政金融协同支持新型农村集体经济的政策体系。本研究分析财政金融协同支持新型农村集体经济的内在机理,基于成都“农贷通”和浙江“千万工程”典型性案例,探究财政协同支持集体经济的可能路径。研究发现,新型农村集体经济兼具经营性和社会性两种属性,对于经营属性,财政资金引导是实现财政金融协同扶持的前提条件,金融赋能是资金支持得以发挥效果的重要支撑;对于社会属性,财政金融协同核心关键在于构建投资与金融、社会投入联动机制。基于此,提出相关政策建议:一是强化财政资金政策扶持;二是金融支持上搭建联席会议平台,建立风险共担机制;三是做强县域富民乡村产业,赋能农村集体经济联合;四是明确监管责任,提高财政金融投入资金效率。

关键词：财政金融协同新型农村集体经济农贷通 “千万工程” 金融赋能风险共担