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Forecast Method of Multimode System for Debris Flow Risk Assessment in Qingping Town,Sichuan Province,china

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Journal of Mountain Science 2011年第4期8卷 592-602页

作者： KONG Jiming Key Laboratory of Mountain Hazards and Earth Surface Processes Chinese Academy of Sciences Institute of Mountain Hazards and Environment Chinese Academy of Sciences

The Wenchuan Earthquake of May 12,2008 triggered large numbers of *** heavy rain on 13.August 2010 triggered debris flows with total volume of more than 6 million cubic meters and the debris flows destroyed 500 houses and infrastructure built after the Wenchuan *** study area Qingping Town was located in the northwestern part of the Sichuan Basin of china,which needs the second reconstructions and the critical evaluation of debris *** study takes basin as the study unit and defines collapse,landslide and debris flow hazard as a geo-hazard system.A multimode system composed of principal series system and secondary parallel system were established to evaluate the hazard grade of debris flow in 13. drainage basins of Qingping *** evaluation result shows that 3..43. of study basins(42 basins) and 24.58% of study area,are in extremely high or high hazard grades,and both percentage of basin quantity and percentage of area in different hazard grades decrease with the increase of hazard *** to the geo-hazard data from the interpretation of unmanned plane image with a 0.5-m resolution and field investigation after the Wenchuan Earthquake and 8.13.Big Debris Flow,the ratio of landslides and collapses increased after the Wenchuan Earthquake and the ratios of extremely high or high hazard grades were more than moderate or low hazard grades obviously.23.geo-hazards after8.13.Big Debris Flow in Qingping town region all occurred in basins with extremely high or high hazard grades,and 9 debris flows were in basins with extremely high hazard *** model of multimode system for critical evaluation could forecast not only the collapse and landslide but also the debris flow precisely when the basin was taken as the study unit.

关键词： Multimode System Risk assessment Debris flow Landslide Wenchuan Earthquake Qingping Town

The Synthesis of an Optically Active Intermediate of A-Ring for 1α,25-Dihydroxy Vitamin D_3.Analogs

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chinese Chemical Letters 1998年第5期9卷 431-432页

作者： Yong WU and (School of Pharmacy, West china University of Medical sciences, chengdu 610041)Mei GUAN (The First Hospital, West china University of Medical sciences, chengdu 610041) W china Univ Med Sci Sch Pharm Chengdu 610041 Peoples R China W china Univ Med Sci Hosp 1 Chengdu 610041 Peoples R China

Synthesis of an optically active intermediate 4b for the A-ring of 1a,25-dihydroxyvitamin D3.analogs has been achieved in eight steps, starting from readily available, inexpensive D-(+)-xylose.

关键词： 1α 25-dihydroxyvitamin D_3 D(+)-xylose synthesis

An extended fast algorithm for constructing the Dixon resultant matrix

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Science china Mathematics 2005年第1期48卷 131-143页

作者： ZHAO Shizhong~1 & FU Hongguang~21.chengdu Institute of Computer Applications,chinese academy of {3.,chengdu 610041,china2.Software Engineering Institute,East china Normal University,Shanghai 200062,china 1. chengdu Institute of Computer Applications Chinese Academy of Sciences 610041 Chengdu China 2. Software Engineering Institute East China Normal University 200062 Shanghai China

In recent years,the Dixon resultant matrix has been used widely in the re-sultant elimination to solve nonlinear polynomial equations and many researchers havestudied its efficient *** recursive algorithm is a very efficient algorithm,butwhich deals with the case of three polynomial equations with two variables at *** paper,we extend the algorithm to the general case of n+1 polynomial equations in *** algorithm has been implemented in Maple *** testing the random polyno-mial equations,the results demonstrate that the efficiency of our program is much betterthan the previous methods,and it is exciting that the necessary condition for the existenceof common intersection points on four general surfaces in which the degree with respectto every variable is not greater than 2 is given out in 48×48 Dixon matrix firstly by ourprogram.

关键词： Dixon resultant matrix Sylvester resultant matrix truncated formal power series

Study of Catalysts on the Synthesis of Methyl Acrylate by Hydroesterification of Methyl Formate with Acetylene

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chinese Chemical Letters 2000年第6期11卷 521-524页

作者： Xin Han HUANG Xian Gui YANG Jia Qi ZHANG Zhao Tie LIU(chengdu Institute of Organic Chemistry, chinese academy of {3., chengdu 610041) chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

The catalytic hydroesterification of methyl formate (MF) with acetylene to methyl acrylate (MA) over nickel-based catalysts prepared by impregnation has been comprehensively studied in a fixed bed reactor at 160 similar to 240 degrees C and under 4 similar to 6MPa GHSV: 63.h(-1), CO:N-2:C2H2 = 65:28:7. In present work, we have found a catalyst of 11wt%NiO/Al2O3.(80 similar to 100 mesh) prepared by wet impregnation with NiCl2 aqueous solution, then calcined in air at 500 degrees C for 5 h. The selectivity to methyl acrylate and the conversion of methyl formate over 11wt%NiO/Al2O3.catalyst are higher than other catalysts studied in this paper. The optimum reaction temperature for the hydroesterification of methyl formate with acetylene to methyl acrylate is around 220 degrees C.

关键词： Ni-based catalyst methyl formate methyl acrylate acetylene

Effect of sediment on concentration of dissolved phosphorus in the Three Gorges Reservoir

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International Journal of Sediment Research 2011年第1期26卷 87-95页

作者： CAO Zhijing~1,ZHANG Xinbao~2,and AI Nanshan~3.Institute of Architecture and Environment,Sichuan University,chengdu 610065,china, Institute of Mountain Hazards and Environment,chinese {3. of sciences,chengdu 610041, china, Institute of Architecture and Environment,Sichuan University,chengdu 610065,china, [a] Lecturer Institute of Architecture and Environment Sichuan University chengdu 610065 china [b] Prof. Institute of Mountain Hazards and Environment chinese academy of sciences chengdu 610041 china [c] Prof. Institute of Architecture and Environment Sichuan University chengdu 610065 china

Eutrophication and algal bloom has been occurring in the Three Gorges Reservoir ever since the reservoir’s impoundment in *** concentration of dissolved phosphorus(DP) is one of the main controlling factors for algal *** sediment adsorbs DP thereby affecting the concentration of DP. The effect of the sediment reduction on the DP concentration of the Three Gorges Reservoir is discussed in this *** were taken from the Yangtze River and its tributaries,*** Minjiang River and the Tuojiang *** DP concentration of the water samples and the available phosphorus,total phosphorus,and phosphorus-fixing capacity of the sediment samples were *** amount of phosphorus adsorbed by the sediment was about 3.of the total DP load in the Yangtze *** experiment was done in the lab simulating the DP concentration,sediment concentration,and turbulence. The results showed that quite a high amount of DP was adsorbed by the *** adsorption capacity of the sediment was 13. mg/kg and the highest rate of adsorption was 29 mg/kg·*** Xiluodu Dam is located at nearly 1,100 km upstream of the Three Gorges *** Xiloudu Dam will trap sediment and thence reduce the sediment load entering the Three Gorges Reservoir after impoundment in *** is estimated that the sediment reduction due to the Xiluodu Dam may result in an increase of the DP concentration in the Three Gorges Reservoir by 6.8%.

关键词： Dissolved phosphorus Sediment load reduction Three Gorges Reservoir Adsorption capacity Eutrophication

Synthesis and Structures of New Borophosphates (B_(1-X)M_X)PO_4 (M=Mn,Fe,Co,Ni,Cu) with Orthorhombic Low-Cristobalite Type

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chinese Chemical Letters 1999年第8期10卷 707-708页

作者： Cheng Hua XU Shao Jie LU Gui Ying DENG Fa Li QIU (chengdu Institute of Organic Chemistry. chinese academy of {3., chengdu 610041) Xiamen Univ Dept Mat Sci Xiamen 361005 Peoples R China Xiamen Univ Dept Chem Xiamen 361005 Peoples R China

The first reported (B1-xMx)PO4 (M = Mn, Fe, Co, Ni, Cu) compounds were synthesized by high temperature solid state methods and the structures refined from X-ray powder data. The transition metal substitutions on the boron site stabilized the structure to the orthorhombic low-cristobalite type with average volumes per tetrahedral unit 3.% larger than that in BPO4 and novel catalytic properties are expected. The magnetic data indicate the 3. valences thr the metals.

关键词： Transition-metal borophosphate,synthesis,structure magnetic property

Stereoselective Synthesis of (Z)-2-Acylamido-4-phenylcrotonates

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chinese Chemical Letters 2000年第7期11卷 567-570页

作者： Yi Nong XIE Fan Min FU Ai Qiao MI Yao Zhong JIANG(chengdu Institute of Organic Chemistry, chinese academy of {3.,chengdu 610041) chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

Two practical methods for highly stereoselective synthesis of (Z)-2-acylamido-4-phenylcrotonates 2a similar to b have been developed. The key step in the first route was how to control the acid-catalyzed isomerization of condensation mixtures of alpha-keto ester 5 with carbomite. In the second route the key step was reduction of oxime 8, derived from alpha-keto ester 5, with iron powder in the presence of acetic anhydride.

关键词： (Z)-alpha,beta-dehydroamino acids stereoselective synthesis E -> Z isomerization Fe/Ac2O reduction of oxime

Convenient, Efficient One-Pot Synthesis of Ferrocenylcyanide

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chinese Chemical Letters 2000年第2期11卷 107-108页

作者： Jun Long ZHANG Chun E DONG Yong Gang ZHI Liang Fu ZHANG (chengdu Institute of Organic Chemistry, chinese academy of {3.. chengdu 610041) chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

Convenient. efficient one-pot synthesis of ferrocenylcyanide, which is a very important intermediate in synthesis of chiral ferrocenyl ligands in asymmetric catalysis, is described. The chemical yield is up to 60%.

关键词： Ferrocene. cyanide synthesis.

Soil Evolution Features of Debris Flow Waste-Shoal Land

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Journal of Mountain Science 2009年第2期6卷 181-188页

作者： CUI Peng GE Yonggang ZHUANG Jianqi WANG Daojie Key Laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China Graduate University of chinese academy of sciences Beijing 100049 China

The reclamation and utilization of debris flow waste-shoal land plays an important role in the mitigation and control of debris flow hazards, which thus contributes a lot to the exploitation of insufficient land resources in mountainous areas and the reduction of losses caused by debris flow. The aim of this paper is to discuss the features and mechanism of soil evolution of debris flow waste-shoal land so as to search for the available modes of its reclamation and utilization. The Jiangjiagou Ravine, a typical debris flow ravine, was selected to study soil evolution features of debris flow waste-shoal land based on the analysis of soil physicochemical properties and soil microstructure. It was found that the soil evolution rates of debris flow waste-shoal land varied with different modes of reclamation. For the land which had been reclaimed for less than 10 years, soil evolved most rapidly in paddy fields, and more rapidly in dry farmland than in naturally restored waste-shoal land. For the land which had been used for more than 10 years, the soil evolution rates of dry farmland, naturally restored waste-shoal land and paddy farmland decreased in the file. For the same utilization period of time, significant differences were recognized in soil evolution features under different modes of reclamation. Analysis data showed that soil clay content, soil thickness, the psephicity of skeleton particles and contents of microaggregates (<0.02 mm) in paddy farmland were all highest. Soil nutrients and porosity of dry farmland were better than those of paddy farmland and naturally restored waste-shoal land, and those of paddy farmland were superior to those of naturally restored waste-shoal land. Paddy farmland characterized by rapid pedogenesis, stable evolution and high utilizability was the priority candidate for the reclamation and utilization of debris flow waste-shoal land.

关键词： Debris flow waste-shoal land Reclamation mode Utilization time Soil properties Soil microstructure