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Study on the Mechanism of the Rearrangement Reaction of 3-n-Butylphthalide by Deuterium-Labelling

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chinese Chemical Letters 1997年第6期8卷 479-482页

作者： Bai Ling xu Zong Ru GUO Xiao Tian LIANG Guang Zhong YANG (institute of Materia Medica, chinese academy of Medical sciences, Peking Union Medical College, {5. 10005.) chinese ACAD MED SCI PEKING UNION MED COLLINST MAT MEDBEIJING 100050PEOPLES R CHINA

By the Grignard reaction of 1,1-di-deutero-1-bromobutane with phthalaldehydic acid 1',1'-di-deutero-3-n-butyl phthalide was obtained, which underwent a rearrangement reaction using AlCl3 as catalyst in CS2 to give 1-methyl-5.carboxy-3,4-di-deutero-tetrahydronaphthalene. The mechanism was proposed to be a series of consecutive 1,2- hydride transfers rather than a direct 1,4-hydride transfer.

关键词： ppm CHD Study on the Mechanism of the Rearrangement Reaction of 3-n-Butylphthalide by Deuterium-Labelling

Plateau Marsh Methane Oxidation as affected by Inorganic N

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Pedosphere 2004年第2期14卷 195-204页

作者： WANGZhi-Ping DUANYi YANGJu-Rong LILing-Hao HANXing-Guo LaboratoryofQuantitativeVegetationEcology InstituteofBotanyChineseAcademyofSciencesBeijing100093（China）／E-mail：wangzp5@*** StateKeyLaboratoryofGasGeochemistry LanzhouInstituteofGeology.ChineseAcademyofSciencesLanzhou730000（China） CollegeofResourceandEnvironment BEijingNormailUniversityBeijing100875（China）

In a series of laboratory incubations using soils of two contrasting sitesfrom a temperate marsh on the Qinghai-Tibet Plateau, potential methane (CH_4) oxidation rates weremeasured to study the effects of inorganic N inputs on CH_4 oxidation. For adrained site, subsurfacepeat (5.-15.cm) at an initial 20 mu L CH_4 L^(-1) showed a significantly different (P 5. CH_4oxidation rate compared to other soil depths, with a maximal rate of 20.9 ng CH_4 gDW (dryweight)^(-1) h^(-1); the underlying mineral soil layers (15.-30 and 30--5. cm) also had a strongCH_4 oxidation capacity at about an initial 2 000 mu L CH_4 L^(-1). With a waterlogged site, theCH_4 oxidation rate in an aerobic incubation was significantly greater (P 5. in the surfacesoil layer (0--5.cm) compared to the 15.-30 and 30--5. cm depths. There was generally no or a veryweak effect from addition of NO_3^- on CH_4 oxidation. In marked contrast, NH_4^+ salts, such as(NH_4)_2SO_4, NH_4Cl and NH_4NO_3, exhibited strong inhibitions, which varied as a function of theadded salts and the initial CH_4 level Increasing NH_4^+ usually resulted in greater inhibition andincreasing initial CH_4 concentrations resulted in less NH_4^+ inhibition on CH4 oxidation innatural high-altitude, low-latitude wetlands could be as important as has been reported foragricultural and forest soils. The NH_4^+ effects on the CH_4 oxidation rate need to be furtherinvestigated in a wide range of natural wetland soil types.

关键词： ammonium inhibition inorganic N methane oxidation plateau marsh

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东濮凹陷深层异常温压条件下的油气生成特征

石油学报 2003年第2期24卷 30-33页

作者：李健中国科学院地质与地球物理研究所北京100083

运用石油与天然气生成理论 ,讨论了东濮凹陷深层异常温压条件下烃源岩热演化的异常现象。研究表明 ,与正常压力油气热演化规律相比 ,异常高压作用下 ,烃源岩热演化程度明显偏低 ,有机质热演化程度与其受热史不匹配 ,有机质的热演化明显... 详细信息

运用石油与天然气生成理论 ,讨论了东濮凹陷深层异常温压条件下烃源岩热演化的异常现象。研究表明 ,与正常压力油气热演化规律相比 ,异常高压作用下 ,烃源岩热演化程度明显偏低 ,有机质热演化程度与其受热史不匹配 ,有机质的热演化明显受到抑制。只有地层压力达到一定门限值时 ,才会明显发生这种现象。在东濮凹陷 ,当压力系数大于 1 5. ,有机质的热演化出现明显异常。对深层异常温压条件下烃源岩的生烃潜力研究表明 ,深层烃源岩仍然具有较高的生烃潜力。同时对该区深层含烃流体相态、储集性及深部盖层封闭性能等问题进行的分析表明。

关键词：东濮凹陷深层温压异常烃源岩热演化异常生烃潜力

Slope Reinforcement for Housing in Three Gorges Reservoir Area

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Journal of Mountain Science 2011年第2期8卷 314-320页

作者： WU Faquan LUO Yuanhua CHANG Zhonghua institute of geology and geophysics Chinese Academy of Sciences Beijing 100029 China Office of Three Gorges Project Construction Committee the State Council of China Beijing 100038 China

The Three Gorges Project of the Yangtze River is the largest hydropower-complex project under construction in the world. Under the largescale relocation projects, 2874 engineered slopes are formed along with the construction of new towns. In this paper, the cutting slopes are mainly soil slopes and rock slopes. Soil slopes include residual soil slopes, colluvial accumulation slopes, swelling soil slopes, and artificial earth fill slopes, etc. Rock slopes include blocky structure rock slopes, layer structure rock slopes, and clastic structure rock slopes, etc. Varied protection measures have been used for slope protection in the reservoir area including shotcrete concrete-anchor bars, frame beams, retaining walls, slope stabilizing piles, sheet-pile walls, anchorage anti-shear tunnels, flexible protection grids, and drainage, etc. Besides, slope deformation monitoring systems have been set up to monitor deformation failure and the stability state of slopes. The protection measures have guaranteed slope safety and maintained a harmony with the urban environment and surrounding landscape.

关键词： Slope reinforcement Housing for resettlement Three Gorges Reservoir

Sporopollen analysis of Core B10 in the southern Yellow Sea and the reflected characteristics of climate changes

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chinese Science Bulletin 2003年第B06期48卷 42-48页

作者： FU Mingzuo~(1,2,3), LI Zhen~1, xu Xiaowei~1 & SHl xuefa~1 1. Key Laboratory of Marine Sedimentology and Environmental geology, First institute of Oceanography. State Oceanic Administration, Qingdao 266061. China 2. institute of Oceanology,{5., Qingdao 266071. China 3. Graduate School,{5., {5. 100039. China 1. Key Laboratory of Marine Sedimentology and Environmental geology First institute of Oceanography State Oceanic Administration 266061 Qingdao China 2. institute of Oceanology Chinese Academy of Sciences 266071 Qingdao China 3. Graduate School Chinese Academy of Sciences 100039 Beijing China

Eight sporopollen zones have been divided based on the results of high-resolution sporopollen analysis of Core B10 in the southern Yellow Sea. Based on the results along with ^14C datings and the subbottom profiling data,climatic and environmental changes since the last stage of late Pleistocene are discussed. The main conclusions are drawn as follows: (1) the vegetation evolved in the process of coniferous forest-grassland containing broad-leaved trees→coniferous and broad-leaved mixed forest→coniferons and broad-leaved mixed forest-grassland prevailed by coniferous trees→coniferous and broad-leaved mixed forest-grassland containing evergreen broad-leaved trees→coniferons and broad-leaved mixed forest-grassland prevailed by broadleaved trees→deciduous broad-leaved forest-meadow containing evergreen broad-leaved trees→coniferous and broadleaved mixed forest-grassland prevailed by broad-leaved trees→coniferous and broad-leaved mixed forest containing evergreen broad-leaved trees; (2) eight stages of climate changes are identified as the cold and dry stage, the temperate and wet stage, the cold and dry stage, the warm and dry stage, the temperate and wet stage, the hot and dry stage, the temperate and dry stage, then the warm and dry stage in turn; (3) the sedimentary environment developed from land,to littoral zone, to land again, then to shore-neritic zone; and (4) the Yellow Sea Warm Current formed during early-Holocene rather than Atlantic stage.

关键词：中国黄海气候变化碳14年代测定底基压型数据更新世沉积环境大西洋

Approximation of dense-n/2-subgraph and table compression problems

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Science China Mathematics 2005年第9期48卷 1223-1233页

作者： xu Dachuan~1 HAN Jiye~2 & DU Dongle~3 1. College of Applied sciences,beijing University of Technology,beijing 100022,China 2. institute of Applied Mathematics,{5. of Mathematics and Systems Science,{5. {5. of sciences,beijing 100080,China 3. Faculty of Administration,University of New Brunswick,P.O.Box 4400,Fredericton,NB E3B 5.3,Canada College of Applied sciences Beijing University of Technology Beijing 100022 China institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2-subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5.82 and 0. 5.70-approximation algorithms respec- tively for the dense-n/2-subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 6243 and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5.bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2-subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

Experimental Study of the Melting Reaction and Genetic Mechanism of Mineral Phase Transformation in Granulite Facies Metamorphism

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Acta Geologica Sinica(English Edition) 1997年第4期71卷 407-422,511页

作者： Liu Fulai, Shen Qihan, Geng Yuansheng institute of geology, chinese academy of Geological sciences, {5. 100037xu xuechun and Ma Rui Open Laboratory, Changchun College of geology, Changchun, Jilin 130026 institute of geology Chinese Academy of Geological Sciences Beijing 100037 Open Laboratory Changchun College of Geology Changchun Jilin 130026 [?]Liu Fulai Born in 1963 got his doctor's degree in 1995.at Changchun Geological College. He is undertaking postdoctoral research on metamorphic petrology and Precambrian geology in the institute of geology Chinese Academy of Geological Sciences.

The high-temperature and high-pressure experiment on natural block rock indicates that dehydration-melting of hydrous biotite (Bi) and partial melting of felsic minerals in garnet-biotite-plagioclase gneiss are mainly controlled by temperature, while mineral phase transformation is not only controlled by temperature-pressure conditions but also genetically associated with hydrous mineral dehydration-melting and partial melting of felsic minerals. According to the characteristics of biotite dehydration-melting and garnet transformation reaction, three stages may be distinguished: (1) when the experimental temperature is 700℃, biotite transforms to ilmenite (Ilm) + magnetite (Mt) + H2O and garnet to magnetite (Mt); (2) when the temperature is 730-760℃, biotite is dehydrated and melted and transformed into K2O-rich melt + Ilm + Mt, and garnet, into hypersthene (Hy) + cordierite (Crd); (3) when the temperature is up to or higher than 790℃, biotite is dehydrated and melted and transformed into melt + Hy + Ilm + Mt, and garnet, into the hypersthene (Hy) + spinel (Sp) + cordierite (Crd) assemblage. The melt proportion and its evolutionary characteristics are mainly controlled by dehydration-melting of hydrous minerals and partial melting of felsic minerals besides P-T conditiops: In addition to the traditional solid 4- solid (or fluid) reaction and dehydration-melting reaction, the metamorphic reaction involving melts (reaction between unmelted minerals and melts) is one of the most important reactions in granulite facies metamorphism and its attendant remelting (or regional migmatization). This experiment may provide dependable experimental data for an in-depth study of the genetic mechanism of mineral assemblage evolution and its geological dynamic significance in granulite facies metamorphism of the studied area.

关键词： mineral phase transformation melting reaction genetic mechanism granulite facies garnet-biotite-plagioclase gneiss experiment

EQUILIBRIUM MOLECULAR DYNAMICSCALCULATION OF THE SHEAR VISCOSITY OFWATER AT HIGH TEMPERATURSS AND PRESSURES

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Scientia Geologica Sinica 1998年第4期 559-567页

作者： Guo Yonggui(institute of geology, chinese academy of sciences, beijing 1.0029)Nie GaoZhong(institute of geology National Bureau of Seismology, beijing. 1.0029)Zhang Yigang(institute of geology chinese academy of sciences, beijing, 1.0029)

In this paper, we present an equilibrium molecular dynamics simulation of 216 water molecules using theTIP4P model. The shear viscosity in the temperature range of 65. to 814K and in the density range of0.5.60 to 0.86389/cm3 were calculated from Green-Kubo formula and compared with availableexperimental data. The averaged absolute difference betWeen simulated results and experimental data is1 5., which is better than the case using non-equilibrium molecular dynamics. The equilibrium moleculardynamics simulation is proved to be another effective method to obtain transpoft properties of water andmay possibly applied to other fluid systems.

关键词： AT In EQUILIBRIUM MOLECULAR DYNAMICSCALCULATION OF THE SHEAR VISCOSITY OFWATER AT HIGH TEMPERATURSS AND PRESSURES SPC high

Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science China Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1,2, xu Chenghua1, FENG Liangrong1, SUO Jishuan1 & QIU Fali1 1. Chengdu institute of Organic Chemistry, chinese academy of sciences, Chengdu 610041, China 2. Graduate School of the chinese academy of sciences, beijing 100039, China 1. Chengdu institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

The present work synthesizes La-Cu4FeAlCO3 catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3 has a hydrotalcite structure. In the phenol hydroxylation with H2O2 catalyzed by La-Cu4FeAlCO3, the effects of reaction time and phenol/H2O2 molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2O2 and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 5..09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3, under the reaction conditions of the molar ratio of phenol/H2O2 1/2, the amount ratio of phenol/catalyst 20, reaction temperature 343 K, reaction time 120 min, 10 mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3 ][C 6 H 5.OH][H 2 O 2]. and the activation energy of Ea=5..37 kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3/H2O2 system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.