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Correlation of coral fluorescence with nearshore rainfall and runoff in Hainan Island, South china Sea

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Progress in Natural Science:Materials International 2002年第1期 43-46页

作者： PENG Zicheng, HE Xuexian, ZHANG Zhaofeng, ZHOU Jie, SHENG Liusi and GAO Hui( Department of Earth and Space Science, university of Science and Technology of china, Hefei 23.026, china State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, {3. academy of sciences, Xi' an 710043. china National Synchrotron Radiation Laboratory, university of Science and Technology of china, Hefei 23.026, china. ) Department of Earth and Space Science，university of Science and Technology of china，Hefei 23.026，china State Key Laboratory of Loess and Quaternary Geology，Institute of Earth Environment，chinese academy of sciences，Xi'an 710043.{3. Department of Earth and Space Science，university of Science and Technology of china，Hefei 23.026，china State Key Laboratory of Loess and Quaternary Geology，Institute of Earth Environment，chinese academy of sciences，Xi'an 710043.{3. National Synchrotron Radiation Laboratory，university of Science and Technology of china，Hefei 23.026，china.

Under UV-laser excitation, the Porites coral from Longwan bay waters, Hainan Island, could emit yellow-green fluorescence. After fitting the data of the fluorescent intensity (FI) of the coral with the rainfall (RF) in nearshore area of Qionghai, a good relationship between FI and RF was found with a linear formula of RF= 889 - 4. 54 FI and a correlation coefficient of 0.78. Based on this formula, the rainfall sequence from 1982 to 1997 has been reconstructed. The peak annual rainfall is usually related to global El'nino events. By fitting the data of the fluorescent intensity and the runoff (RO), a quadric formula was obtained as RO = - 0.0279FI2 - 18.59 FI- 950.9 with a correlation coefficient of 0.74. The reconstructed runoff sequence from 1982 to 1997 coincided with the rainfall occurrence . The results indicate that flood and drought incidents in coastal areas of the south china are affected by global change to a great extent.

关键词： UV laser coral fluorescence nearshore rainfall river mouth runoff correlation analysis.

基于FPGA的GPS接收机相关器技术研究与实现

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系统仿真学报 2011年第7期23卷 1513-1517,1521页

作者：胡辉袁超吴超高明华华东交通大学信息工程学院南昌330013 中国科学院光电研究院北京100094

利用EDA技术和FPGA技术,研制出具有自主知识产权基于FPGA的GPS相关器。采用本地产生C/A码的超前、即时、滞后码与输入信号进行并行相关,并得到预检测值用于捕获GPS信号;重点设计载波NCO相位、载波周数、码相位、历元计数等测量数据产生... 详细信息

利用EDA技术和FPGA技术,研制出具有自主知识产权基于FPGA的GPS相关器。采用本地产生C/A码的超前、即时、滞后码与输入信号进行并行相关,并得到预检测值用于捕获GPS信号;重点设计载波NCO相位、载波周数、码相位、历元计数等测量数据产生模块,含该模块的GPS相关器可用于实现导航型和测量型接收机;阐述了GPS相关器各个模块的详细设计,并用VHDL在FPGA中实现了其全部设计。在Modelsim下进行功能仿真和时序仿真,仿真正确后下载到Xilinx Virtex-II Pro开发板中进行验证。运行结果表明设计的GPS相关器与微处理器配合可以完成GPS信号的基带信号处理。

关键词： GPS 相关器 FPGA ISE Modelsim仿真

Cardioprotection of intermittent hypoxia adaptation: regulation of Ca2+ homeostasis

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Cardioprotection of intermittent hypoxia adaptation: regulat...

Conservation and Sustainable Exploitation of Forest Ecosystem in Upper Reaches of the Yangtze River -Case Study on Gongga Mountain

中国生理学会第五届全国心血管、呼吸和肾脏生理学学术会

作者： Huang-Tian Yang (Laboratory of Molecular Cardiology, Institute of Health sciences, Shanghai Institutes for Biological sciences, chinese {3. of sciences & Shanghai Second Medical university, Shanghai, 200025)

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chinese Forestry Science and Technology 2003年第1期2卷 66-70页

作者： ZHANG Baohua HE Yurong ZHOU Hongyi CHENG Genwei Institute of Mountain Hazards & Environment, the chinese academy of sciences.Chengdu 610041. {3.. Department of Geography, Liaocheng university, Liaocheng 252059. {3. bhz@ imde. ***

The deforestation on large scale in the upper reaches of Yangtze River has caused serious problems of ecosystem and environment. Restoration of the degenerated forest ecosystems is one of the main research fields. Taking Gongga Mountain as an example, degeneration features and existing problems of forest ecosystems are analyzed in this paper, and the measures are also proposed.

关键词： conservation and sustainable exploitation forest ecosystem upper reaches of the Yangtze River Gongga Mountain

ADAPTIVE CALIBRATION OF I AND Q MISMATCH IN QUADRATURE RECEIVER

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Journal of Electronics(china) 2002年第2期19卷 187-191页

作者： YangXuexian ZhangQunying 等 InstituteofComputingTechnology ChineseAcademyofSciencesBeijing100080 InstituteofElectronics ChineseAcademyofSciencesBeijing100080

The mismatch of ill-phase and quadrature channels in quadrature receiver affects and constrains radar detection performance in coherent radar. It is necessary to keep the in-phase and quadrature branches symmetrical. In this letter, an adaptive method t.o detect imbalance parameters is derived by means of evaluating channel errors from the received signal .sequences. No matter how the bias degree of the gain and phase errors in I/Q channels are. the proposed adaptive scheme can obtain good calibration results. And the inquired calculations are only a few multiplications and additions. No need of a special test signal, the introduced method is simple to implement and easy to operate.

关键词： Quadrature receiver I/Q mismatch Adaptive' calibration

Receptive field modification induced by natural scenes stimulation in rat visual cortex

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Receptive field modification induced by natural scenes stimu...

X—RAY STRUCTURE OF A SEMICONDUCTING ORGANOMETALLIC SALT,[FeCp(Tol)]_2[Ni(mnt)_2]

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： Ying-Jie ZHU,Hai-Shan YAO~* Institute of Neuroscience,State Key Laboratory of Neuroscience,Shanghai Institutes for Biological sciences,chinese academy of sciences,Shanghai,20003.,china

＜正＞Objective Visual experience can cause functional modification in the adult visual cortex,but the mechanisms of cortical modification under natural stimulation remain to be *** present study is to explore whether and how the natural scenes stimulation modify the receptive field（RF） of neurons in rat *** In this study,we used in vivo patch recordings in rat V1 to examine the receptive field（RF） modification induced by stimulation of natural scenes movies. RF map was measured with sparse noise before and after repetitive stimulation of natural movie（25-sec long,repeated 25 times）.Results（1） Natural movie stimulation caused heterogeneous modifications in the local synaptic responses,with some responses enhanced and some depressed.（2） The changes in local synaptic responses caused change in the global structure of synaptic RF *** examine the relationship between RF modification and the movie images,we first grouped the images into three subsets:images that caused depolarization（S+）,images that caused hyperpolarization（S-）,and images that did not change the mean membrane *** then quantified the similarity between RF map and each movie image by calculating their correlation coefficient（CC）.After the movie stimulation,the CCs between S+ images and RF were significantly shifted toward positive values,whereas the CCs between S- images and RF did not change significantly,indicating the RF is modified to become more similar to the subset of movie images that can depolarize the cell.（3. In the absence of further movie stimulation,the modification can last for 5 to 10 min.（4） Repeated exposure to white noise did not cause significant change in the CCs,indicating the RF modification is stimulus specific.（5） The magnitude of the modification was dependent on the spiking activity of the neuron evoked by the movie.（6） Associated with the change in RF spatial structure,spike rate of the neuron during movie stimulation selectively increased for those im

关键词： receptive field modification V1 natural scenes Hebbian synaptic plasticity

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chinese Chemical Letters 1993年第6期4卷 561-562页

作者： Wei Hua ZHOU Jin Gui QIN Dao Yu LIU Department of Chemistry,Wuhan university,Wuhan 43.072Ning Hai HU Zhong Sheng JIN Changchun Institute of Applied Chemistry,chinese academy of {3.,Changchun 13.022

The title compound was prepared and *** crystal Structure was determined by X—ray diffraction analysis,and consists of segregated cation and an- ion stacks in the perpendicular *** data:monoclinic,P2_1/c,Mr=765.21, a... 详细信息

关键词： FeCp RAY STRUCTURE OF A SEMICONDUCTING ORGANOMETALLIC SALT Tol mnt Ni

Microbial Community Structure of Casing Soil During Mushroom Growth

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Pedosphere 2009年第4期19卷 446-452页

作者： CAI Wei-Ming YAO Huai-Ying FENG Wei-Lin JIN Qun-Li LIU Yue-Yan LI Nan-Yi ZHENG Zhong Department of Plant Protection Zhejiang University Hangzhou 310029 (China) Horticulture Institute Zhejiang Academy of Agricultural Sciences Hangzhou 310021 (China) Zhejiang Provincial Key Laboratory of Subtropical Soil and Plant Nutrition Zhejiang University Hangzhou 310029 (China)

The culturable bacterial population and phospholipid fatty acid （PLFA） profile of casing soil were investigated at different mushroom （Agaricus bisporus） cropping stages. The change in soil bacterial PLFAs was always accompanied by a change in the soil eulturable bacterial population in the first flush. Comparatively higher culturable bacterial population and bacterial PLFAs were found in the casing soil at the primordia formation stage of the first flush. There was a significant increase in the ratio of fungal to bacterial PLFAs during mushroom growth. Multivariate analysis of PLFA data demonstrated that the mushroom cropping stage could considerably affect the microbial community structure of the casing soil. The bacterial population increased significantly from casing soil application to the primordia formation stage of the first flush. Casing soil application resulted in an increase in the ratio of gram-negative bacterial PLFAs to gram-positive bacterial PLFAs, suggesting that some gram-negative bacteria might play an important role in mushroom sporophore initiation.

关键词： cropping stage culturable bacterial population phospholipid fatty acid

Temporal properties of binocular cell responses and experience-dependent binocular competition in mouse V1

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Temporal properties of binocular cell responses and experien...