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Changes in the sediment load of the Lancang-Mekong River over the period 1965-2003

Science China(Technological Sciences) 2013年第4期56卷 843-852页

作者： LIU Cheng he Yun WALLING Des E WANG JianJun International Research and Training Center on Erosion and Sedimentation China Institute of Water Resources and Hydropower Research Department of Geography College of Life and Environmental SciencesUniversity of ExeterExeterDevonEX4 4RJUK Department of Geodesy and Geomatics Engineering University of New BrunswickFrederictonNBCanadaE3B 5A3

Changes in the sediment load of a river can have important impacts on river channel evolution,nutrient fluxes,aquatic ecology and delta erosion and sedimentation,and the possibility of changes in the sediment load of the Lancang-Mekong River has attracted increasing concern in recent *** studies present conflicting findings regarding the nature and magnitude of recent changes in the sediment load of the Lancang-Meking River and the authors have attempted to assemble the most reliable data on annual sediment loads for the period 1965-2003,to assess recent trends in the sediment load of the *** changes in annual sediment load at 7 stations on the river are *** sediment contributing areas are found in the reaches between Gajiu and Yunjinghong,Chiang Saen and Luang Prabang and downstream of Nong *** sediment load increased at Gajiu,Yunjinghong and Chiang Saen over the period 1985-1992 because of serious soil erosion caused by the expansion of cultivation,the replacement of natural forest by plantations and land disturbance associated with hydropower dam construction.A marked reduction in sediment load occurred at Gajiu after the impoundment of the Manwan Hydropower dam on the Lancang River,but this reduction was not evident downstream at Yunjinghong and the stations further *** increases in sediment load appeared at Mukdahan and Khong *** contrasting patterns of change reflect the influence of sediment contributions from the intervening catchment areas and channel systems as well as storage and remobilization of sediment from the channel system and the impact of hydraulic works such as irrigation *** long term mean annual sediment load of the Mekong River at its mouth is estimated to be ca.145×106ta-1,which is lower than previously reported values and it seems likely that this will be reduced in the foreseeable future.

关键词： Lancang River Lower Mekong River sediment load runoff trends hydropower dams

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Design and analysis of a mode-hop-free tunable laser based on etched diffraction grating

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第10期11卷 793-797页

作者： Rui-xing ZENG Lei WANG Jian-jun he Center for Integrated Optoelectronics State Key Lab of Modern Optical Instrumentation Zhejiang University Hangzhou 310027 China

A novel semiconductor laser which can achieve mode-hop-free tuning is proposed. The device consists of an etched diffraction grating （EDG） as a dispersive element to provide the mode selection function and an active waveguide to provide optical gain for the laser. The slab waveguide region of the EDG contains a tuning section covered by an electrode to inject a tuning current, and thus changes the refractive index. Mode-hop-free tuning is achieved by specially designing the shape of the tuning section, so that the tuning rate of the central wavelength reflected by the EDG and the tuning rate of the resonant wavelength of the laser cavity are equal. An optimized tuning section shape is designed to obtain the largest tuning range within a limited current range. Numerical simulation is presented to demonstTate the mode-hop-free tuning operation.

关键词： Semiconductor laser Integrated optics Etched diffraction grating

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NEW ALDALOIDS TONGOLINE AND TONGOLININE FROMDELPHINIUM TONGOLENSE

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Chinese Chemical Letters 1996年第6期7卷 557-560页

作者： he, L Chen, YZ Ding, LS Li, BG LANZHOU UNIV DEPT CHEMLANZHOU 730000PEOPLES R CHINA ACAD SINICA CHENGDU INST BIOLCHENGDU 610041PEOPLES R CHINA

Two new diterpenoid alkaloids, tongoline (1) and tongolinine (2) were isolated from the whole plants of Delphinium tongolense F.. Their structures were determined on the basis of spectral data.

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Preparation and Sensitivity of SnO2 Grafted MCM-41 Sensor

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Chinese Chemical Letters 2005年第8期16卷 1071-1073页

作者： Guo Hua GAO Sibudjing KAWI Ming Yuan he Shanghai Key Laboratory of Green Chemistry and Chemical Process Department of Chemistry East China Normal University Shanghai 200062 Department of Chemical and Biomolecular Engineering National University of Singapore Singapore 119260

SnO2 grafted MCM-41 sensor was prepared by MOCVD in the pore of MCM-41. The sensor has high sensitivity for carbon monoxide at low temperature compared with commercially available low-surface-area tin dioxide.

关键词： Sensor mesoporous Sn02 CO sensitivity.

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Composition Operators from Hardy-Orlicz Spaces to Bloch-Orlicz Type Spaces

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Journal of Mathematical Research with Applications 2018年第5期38卷 458-464页

作者： Zhonghua he School of Financial Mathematics and Statistics Guangdong University of Finance

Let φ be an analytic self-map of D. The composition operator C;is the operator defined on H（D） by C;（f） = f ? φ. In this paper, we investigate the boundedness and compactness of the composition operator C;from H... 详细信息

关键词： composition operator Hardy-Orlicz space Bloch-Orlicz space

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Diethyl　Tartrate　on　Polystyrene　Bead　as　Chiral　Stationary　Phase　in　Liquid　Chromatography

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Chinese Chemical Letters 1996年第11期7卷 1035-1036页

作者： Liu, QY Wu, XJ he, JG Liu, GQ CHINESE ACAD SCI INST CHEMBEIJING 100080PEOPLES R CHINA

L0-(+)-diethyl tartrate was bound to hydroxymethyl polystyrene bead as a chiral stationaryphase in high-performance liquid chromatography(HPLC) for the resolution of pharmaceuticallyracemic compounds, such as D,L-amyg... 详细信息

关键词： Tartrate Bead

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Effects and Mechanisms of RE on Impact Toughness and Fracture Toughness of Clean heavy Rail Steel

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Journal of Iron and Steel Research International 2011年第3期18卷 52-58页

作者： LIU Cheng-jun HUANG Ya-he JIANG Mao-fa School of Materials and Metallurgy Northeastern UniversityShenyang 110004LiaoningChina

Clean high carbon heavy rail steel was prepared by the process of vacuum induction furnace smelting,forging and *** of RE on the impact toughness and fracture toughness for clean high carbon steel were *** addition,the appropriate range of RE content for clean high carbon steel was *** the austenite grain size and pearlite lamellar spacing decreased due to small amount of RE,consequently the impact toughness and fracture toughness were improved *** the RE content exceeded a critical value,the pearlite lamellar spacing was increased,because RE was segregated on the austenite grain boundaries,damaged the orientation relationship of pearlite transformation,caused the disorder growth and morphology degenerating of *** the increasing of RE content,both the impact toughness and fracture toughness of clean high carbon steel were gradually increased at first and then *** was found that when the RE content was between 0.0081% and 0.0088%,both the impact toughness and fracture toughness of clean high carbon heavy rail steel were the *** maximum ballistic work was 21.2 J（20 ℃） and 12.2 J（-20 ℃）,*** maximum plane-strain fracture toughness was 45.67 MPa·m1/2（20 ℃） and 37.04 MPa·m1/2（-20 ℃）,respectively.

关键词： rare earth high carbon steel heavy rail steel clean steel impact toughness fracture toughness

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Effect of Hydrolysis Catalysts on Structural Evaluation of Sol-Gel Derived Titania Nanocrystalline Powders

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Chinese Physics Letters 1995年第2期12卷 123-125页

作者： DING Xingzhao LUO Ju QI Zhenzhong he Yizhen Institute of Solid State Physics Academia SinicaHefei 230031

Effect of hydrolysis catalysts(HCl and C_(5)H_(8)O_(2))on structural evaluation of gelderived nanocrystalline TiO_(2) powders was *** temperature of the HCl catalyzed gel is about 200K lower than that of the C_(5)H_(8)O_(2) catalyzed *** in the later gel the anatase phase transforms to rutile at a lower temperature,and the transformation is completed in a much more narrow temperature range.

关键词： catalyzed hydrolysis narrow

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Pyrene Excimer-based Bis-triazolyl Pyranoglycoligands as Specific Mercury Sensors

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Chinese Journal of Chemistry 2012年第12期30卷 2874-2878页

作者： he Xiaopeng Xie Juan Chen Guorong Chen Kaixian Key Laboratory for Advanced Materials & Institute of Fine Chemicals East China University of Science and Technology Shanghai 200237 China PPSM Institut d'Alembert ENS de Cachan CNRS UMR 8531 61 Avenue du pt Wilson F-94235 Cachan France State Key Laboratory of Drug Research Shanghai Institute ofMateria Medica Chinese Academy of Sciences Shanghai 201203 China

New C3,4-disubstituted bis-triazolyl glycoligands that feature a glucosyl or galactosyl scaffold incorporating two pyrenyl groups were synthesized via the Cu^1-catalyzed azide-alkyne 1,3-dipolar cycloaddition reaction （Cue-AAC）. These compounds exert a major emission band corresponding to that of pyrene excimer and respond specifically to mercury with a markedly quenched fluorescence. The epimeric nature of the pyranoglycosyl scaffold is determined influential toward the selectivity of the sensors.

关键词： glycoligand click chemistry sugar mercury chemosensor

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Optimization of parental RNAi conditions for hunchback gene in Locusta migratoria manilensis （Meyen）

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Insect Science 2010年第1期17卷 1-6页

作者： Zheng-Bo he Yue-Qing Cao Yu-Xian Xia Genetic Engineering Research Center College of Bioengineering Chongqing University Chongqing Engineering Research Center for Fungal Insecticides and Key Laboratory of Functional Gene and Regulation Technologies under Chongqing Municipal Education Commission Chongqing China

An investigation on the optimization of parental RNA interference （RNAi） conditions for hunchback （hb） gene in Locusta migratoria manilensis （Meyen） was conducted. Double stranded RNA （dsRNA） corresponding to hb gene was injected into haemocoel of female adults ofL. migratoria manilensis. Embryos developed from the eggs laid by the injected adults on the 7th day after eclosion showed observable effects of RNAi for hb. The silencing effect after delivery treatment of dsRNA for hb gene was maintained for more than 21 days. A significant decrease of hb transcripts was further confirmed by Northern blot analysis. The dose of dsRNA/insect at 2μg could trigger 96.9% RNAi effects, while silencing appeared to have no dependence on the size of dsRNA. Results suggest that parental RNAi could be employed to efficiently identify the developmental gene functions in L. migratoria manilensis.

关键词： hunchback Locusta migratoria manilensis parental RNA interference

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