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Modeling sediment transport in the lower Yellow River and dynamic equilibrium threshold value

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Science China(Technological Sciences) 2004年第z1期47卷 161-172页

作者： hu Chunhong guo Qingchao Department of Sediment China Institute of Water Resources and Hydropower Research Beijing 100044 Department of Sediment China Institute of Water Resources and Hydropower Research Beijing 100044

A major problem in the lower Yellow River is the insufficient incoming water and excessive sediment supply, which results in serious deposition, continuous rise of the river bed, and austere flood control situation. To understand the sediment transport regularity of the lower Yellow River and determine the relationship between sedimentation, incoming water and sediment, and zone water diversion, a mathematical model of the sediment suitable for the characteristics of the lower Yellow River has been developed. This model is first rated and verified by large quantity of observed data, and it is then used to analyze silting reduction for the lower Yellow River by Xiaolangdi Reservoir’s operation, the relationship between zone water diversion and channel sedimentation, and critical equilibrium of sedimentation in the lower Yellow River. The threshold values of equilibrium of sedimentation in the lower Yellow River are estimated and they suggest that deposition in the lower Yellow River can be effectively reduced by the operation of regulating flow and sediment from Xiaolangdi Reservoir, water-soil conservation, and controlling water diversion along the lower Yellow River.

关键词： the lower Yellow River, mathematical model of sediment, threshold value, zone water diversion,sedimentation reduction.

Particle filter based stochastic interference cancellation for frequency-selective MIMO channel equalization

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Journal of Systems Engineering and Electronics 2007年第3期18卷 476-483页

作者： Yang Tao hu Bo guo Xinyue Dept. of Electronics Engineering Fudan Univ. Shanghai 200433 P. R. China

To mitigate the effects of the previous symbol decision errors of a decision-feedback （DF） equalizer on the current decision, a particle filter （PF） based DF equalizer for frequency selective multiple-input-multiple-output （MIMO） channel is proposed. On the basis of the analyses of DF equalization for the MIMO wireless system, it is found that a stochastic interference cancellation （IC） scheme can be employed to prevent the error propagation in a severe space-time interference scenario. This is because the random rather than the deterministic scheme can reduce the probability of an error decision even if an error decision occurs. Besides, the signal-to-interference-plus-noise ratio （SINR） based IC order, which is obtained via pilot, can guarantee the optimality of the cancellation. The bit error rate （BER） performance of the proposed scheme is verified through simulation experiments under different multipath interference environment.

关键词： multiple-input-multiple-output particle filter pilot decision-feedback interference cancellation.

Novel estradiol sensors based on carbon nanotube multilayer modified gold hair microelectrodes

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Chinese Chemical Letters 2009年第10期20卷 1248-1250页

作者： Jun hui Xu Cheng guo hu Sheng Shui hu Department of Chemistry Wuhan University Wuhan 430072 China State Key Laboratory of Transducer Technology Chinese Academy of Sciences Beijing 100080 China

Multi-walled carbon nanotube multilayers were modified onto a newly proposed gold hair microelectrode via a simple layer-bylayer assembling method. The resulting electrode showed a sensitive oxidation response to estradiol with detection limit as low as 1.0 × 10^-8 mol/L, foreseeing a promising approach to the fabrication of high-sensitive microsensors.

关键词： Layer-by-layer assembly Carbon nanotubes Hair microsensors Estradiol

Predominating stable adsorption and direct electrochemistry of glucose oxidase on carbon nanotubes by oxygen-containing groups

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Chinese Chemical Letters 2007年第3期18卷 313-315页

作者： Chun Hai Yang Cheng guo hu Sheng Shui hu Departraent of Chemistry Wuhan University Wuhan 430072 China Key Laboratory of Biological Resources Protection and Utilization of hubei Province Enshi 445000 China

Stable adsorption and direct electrochemistry of glucose oxidase （COx） occurred on nitric acid （HNO3）-treated multi-walled carbon nanotubcs （MWNTs） instead of as-received MWNTs, demonstrating the critical roles ... 详细信息

关键词： Glucose oxidase Adsorption Direct electrochemistry Carbon nanotubes Oxygen-containing groups

Characterization of W80Cu20 alloy sheet prepared by hot-rolling

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Rare Metals 2013年第6期32卷 569-573页

作者： hu-Ping guo Wen-Ge Chen hui Zhang School of Materials Science and Engineering Xi'an University of Technology

Multi-pass hot-rolling technique was used to fabricate W80Cu20 alloy,and its properties were characterized in this *** show that the W-Cu alloy sheets with a thickness of 0.5 mm and a relative density of99.87%can be successfully made using this new technique at 800℃.In hot-rolling process,Cu phases are closely surrounded by W particles under the rolling stress to form a network microstructure,thus making significant increase in electrical and thermal conductivity up to53.00%and 24.44%,*** and longitudinal hardness of the W–Cu sheets significantly increase due to the enhanced densification and deformation *** to that of the raw materials,three fracture types were observed in the hot-rolled materials,i.e.,ductile fracture of Cu binding phases,trans-granular fracture of W phases,and W–W interfacial fracture.

关键词： Hot-rolling W-Cu alloy Properties Fracture morphology Sheet

Free-Space Optical communication using visible light

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第2期8卷 186-191页

作者： hu guo-yong CHEN Chang-ying CHEN Zhen-qiang Institute of Optoelectronic Engineering Jinan University Guangzhou 510632 China Department of Optoelectronic Engineering Jinan University Guangzhou 510632 China

The possibility of visible red light laser being used as signal light source for Free-Space Optical (FSO) communication is proposed. Based on analysis of transmission in atmospheric channel concerning 650 nm laser beam, performance of wireless laser communication link utilizing a low power red laser diode was evaluated. The proposed system can achieve a maximum range of 300 m at data rate 100 Mb/s theoretically. An experimental short-range link at data rate 10 Mb/s covering 300 m has been implemented in our university. It is feasible to enhance the system performance such as link range and data rate by increasing transmitting power and decreasing laser beam divergence angle or through other approaches.

关键词： Visible light communication Red light laser Free-Space Optical communication Wireless laser communication

Electrochemical determination of sulphide at multi-walled carbon nanotubes-dihexadecyl hydrogen phosphate composite film modified electrodes based on in situ synthesis of methylene blue

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Chinese Chemical Letters 2008年第1期19卷 73-75页

作者： An Min Xiang Li Zhou Cheng guo hu Sheng Shui hu College of Chemistry ＆ Molecular Sciences Wuhan University Wuhan 430072 China State Key Laboratory of Transducer Technology Chinese Academy of Sciences Beijing 100080 China

A novel electrochemical method for the determination of sulphide at a multi-walled carbon nanotube-dihexadecyl hydrogen phosphate composite film coated glassy carbon electrode （MWNTs-DHP/GCE） based on in situ synthesis of methylene blue （MB） was established. 2007 Sheng Shui hu. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： Sulphide determination Electrochemical method Carbon nanotubes Methylene blue

Research progress in protein post-translational modification

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Chinese Science Bulletin 2006年第6期51卷 633-645页

作者： hu Jia guo Yanting LI Yanme Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology Department of Chemistry Tsinghua University Beijing 100084 China

Protein post-translational modification plays an important role in organism. It makes the protein obtain more complicated structures, perfect functions, more accurate regulations and more spe-cific operations. The most common protein post- translational modifications include ubiquitylation, phosphorylation, glycosylation, lipodation, methyla-tion, and acetylation and so on. Ubiquitylation plays an essential role in cellular functions such as cellular differentiation, apoptosis, DNA repair, antigen proc-essing, and stress response. Phosphorylation is re-lated to physiological and pathological processes including cellular signal conduction, nervous activity, muscle contraction and proliferation, development and differentiation of cells. Protein glycosylation is of great importance for many cell processes like im-munoprotection, virus replication, cell growth, and occurrence of inflammation and so on. Lipodation is vital to signal conduction. Histone methylation and acetylation are responsible for transcription regula-tion. In vivo, different post-translational modifications do not occur isolatedly, but influence each other’s function and cooperate with each other. Under-standing what influences the post-translational modi-fications will help to uncover cellular processes and protein network in molecular level and finally direct more precise drug design targeting molecules. Post-translational modification mimics are set to dominate the next wave of protein therapeutics and become powerful medicinal tools in the 21st century.

关键词：蛋白质磷酸化糖基化甲基化乙酰化作用研究进展

Seasonal variation of the temperature profile and its characteristics within urban roughness sublayer

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Chinese Science Bulletin 2009年第3期54卷 468-473页

作者： WANG XiQuan WANG ZiFa guo hu Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China Beijing Meteorological Bureau Beijing 100089 China

By using conventional micro-meteorological observation data of Beijing Yuetan Park Tower (180 m), the temperature profile of urban boundary layer (UBL), its characteristics and seasonal variation are analyzed. The main results are as follows: (1) In winter, the interdiurnal surface air temperature varia- tion at the surface is not synchronized with that of the upper levels, other than in summer and other seasons, which illuminates the impacts of Beijing’s geographical location, sky view factor and stably stratified nocturnal inversion. (2) Except that the stratification is unstable around noon, the stratifica- tion in the roof layer or above-roof layer is of seasonal variability, which is weak unstable or weak sta- ble in winter or summer respectively. This weak stable stratification possibly inhibits urban pollutant dispersion upwards in summer season. (3) The effect of urban building rooftop on the UBL thermal state has seasonal difference, that is, the rooftop plays the role of heating or cooling the urban roughness sublayer, in summer or winter respectively, which is similar to the effects of the Qing- hai-Tibet Plateau on the atmospheric thermal state.

关键词：城市边界层温度季节变更北京