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Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1, YANG De suo 2. ZHANG Jiao qiang 3. (1. Department of Chemistry,Northwest university, Xi′an 710065, {2. 2. Department of Chemistry and Chemical Engineering, Baoji College of Arts and Science, Baoji 72.007, {2. 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Regulation of eight avr genes by hrpG and hrpX in Xanthomonas campestris pv. campestris and their role in pathogenicity

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Progress in Natural Science:Materials International 2006年第12期16卷 1288-1294页

作者： XU Rongqi~ 1,3., LI Xianzhen~3. WEI Hongyu~3. JIANG Bole~2. LI Kai~3. HE Yongqiang~ 2.3., FENG Jiaxun~ 1,3.and TANG Jiliang~ 1,2.**(1. Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization 2. The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering 3. College of Life Science and Technology, Guangxi university, Nanning 53.004, china) Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization Guangxi University Nanning 530004 China College of Life Science and Technology Guangxi University Nanning 530004 China The Key Laboratory of Ministry of Education for Microbial and Plant Genetic Engineering Guangxi University Nanning 530004 China

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004 were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on chinese radish showed that all mutants in individual avr genes except avrBs2.mutant were not significantly different from the wild type in virulence. The avrBs2.mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1.1,avrBs1,avrXccB,avrXccC,avrXccE1 were regulated by hrpG, whereas avrXccA1, avrXccA2.and avrBs2.were not. RT-PCR analysis showed that all hrpG-regulated genes except avrBs1 were also regulated by hrpX. In addition, it was demonstrated that avrBs1 was responsible for elicitation of a type III dependent hypersensitive reaction (HR) on nonhost plant pepper ECW-10R, and wild type Xcc 8004 was unable to cause HR on pepper ECW-2.R.

关键词： Xanthomonas campestris pv. campestris avirulence gene virulence expression analysis.

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan university Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3.,HUANG Zhiqin 2. 3. 4 1. The Faculty of Geography and Resources Science, Sichuan Normal {2., Chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, chinese Academy of Sciences, Chengdu 610041, Sichuan, china 3. graduate {2. of the chinese Academy of Sciences, Beijing 100049, china 4. Information Center of Land and Resources Department of Sichuan Province, Chengdu 610041, Sichuan, china The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China graduate university of the {2. Academy of Sciences 100049 Beijing China Information Center of Land Resources Department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 3.°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Nitrogen isotopic geochemical characteristics of crude oils in several basins of china

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Science china Earth Sciences 2005年第8期48卷 1211-1219页

作者： CHEN Chuanping1,2. MEI Bowen1 & CAO Yacheng3.1. Jianghan Petroleum university, Jingzhou 43.100, china 2. Huazhong university of Science and Technology, Wuhan 43.047, china 3. Nanjing Institute of Soil Science, chinese Academy of Sciences, Nanjing 2.0008, china 1. Jianghan Petroleum university 434100 Jingzhou China 2. Huazhong university of Science and Technology 430047 Wuhan China 3. Nanjing Institute of Soil Science Chinese Academy of Sciences 210008 Nanjing China

Nitrogen isotopic ratios of crude oils with different physical and chemical properties in several basins of china have been measured and their geochemistry has been studied ele-mentally combined with molecular organic geochemistry methods. The data indicate that δ 15N is in the range of ?6‰-2.‰. They vary with the oils in different sedimentary types of basins. The oils forming in the limnic environment have lower δ 15N with the value of about 1‰-5‰ whereas the oils in saline or semi-saline environment have higher δ 15N, with most samples being above 10‰ and some exceeding 17‰. The average nitrogen isotopic ratio of oils from the Ordovician formation in the Tarim Basin is the lowest, with most samples having δ 15N below zero, which reflects possibly the characteristic of the oils originating mainly from the organic matter formed in marine carbonate sedimentary environment. The δ 15N distribution can be altered by fractionation. It increases obviously because of biodegradation and decreases during hydrocarbon migration. However, the effect of nitrogen isotopic fractionation in the short distance migration is uncon-spicuous.

关键词： nitrogen isotope, crude oil, sedimentary environment, isotopic fractionation, china.

Analysis of tandem repeats in the genome of chinese shrimp Fenneropenaeus chinensis

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chinese Science Bulletin 2005年第14期50卷 1462-1469页

作者： KONG Jie1 & GAO Huan2.3.1. Key Laboratory for Sustainable Utilization of Marine Fisheries Re- sources, Ministry of Agriculture, Yellow Sea Fisheris Research Insti- tute, chinese Academy of Fishery Sciences, Qingdao 2.6071, {2. 2. Institute of Oceanology, chinese Academy of Sciences, Qingdao 2.6071, {2. 3. The graduate School of the chinese Academy of Sciences, Beijing 10003., {2. Key Laboratory for Sustainable Utilization of Marine Fisheries Resources Ministry of Agriculture Yellow Sea Fisheris Research Institute Chinese Academy of Fishery Sciences Qingdao China Institute of Oceanology Chinese Academy of Sciences Qingdao China The graduate School of the chinese Academy of Sciences Beijing China

Through random sequencing, we found a total of 884000 base-pairs (bp) of random genomic sequences in the genome of chinese shrimp (Fenneropenaeus chinensis). Using bio-soft Tandem Repeat Finder (TRF) software, 2.59 tandem repeats were found, in which there were 1714 mi- crosatellites and 445 minisatellites, accounting for 79.4% and 2..6% of repeat sequences, respectively. The cumulative length of repeat sequences was found to be 116685 bp, ac- counting for 13.2. of the total DNA sequence; the cumula- tive length of microsatellites occupied 9.78% of the total DNA sequence, and that of minisatellites occupied 3.42.. In decreasing order, the 2. most abundant repeat sequence classes were as follows: AT (557), AC (471), AG (2.4), AAT (92., A (56), AAG (2.), ATC (2.), ATAG (2.), AGG (18), ACT (15), C (11), AAC (11), ACAT (11), CAGA (10), AGAA (9), AGGG (7), CAAA (7), CGCA (6), ATAA (6), AGAGAA (6). Dinucleotide repeats, not only in the aspect of the number, but also in cumulative length, were the preponderant repeat type. There were few classes and low copy numbers of repeat units of the pentanucleotide repeat type, which included only three classes: AGAGA, GAGGC and AAAGA. The classes and copy numbers of heptanucleotide, eleven-nucleotide and thirteen-nucleotide primer-number-composed repeats were distinctly less than that of repeat types beside them.

关键词：虾遗传特性遗传基因 DNA

On conformal measures for infinitely renormalizable quadratic polynomials

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Science china Mathematics 2005年第10期48卷 1411-1420页

作者： HUANG Zhiyong~1 JIANG Yunping~(2.3. & WANG Yuefei~3.1. School of Information,Renmin {2. of china,Beijing 100872.china 2. Department of Mathematics,Queens College,City {2. of New York,NY 113.7,USA Department of Mathematics,graduate School,City {2. of New York,New York,NY 10016,USA 3. Academy of Mathematics and Systems Science,chinese Academy of Sciences,Beijing 100080,china 1. School of Information Renmin University of China 100872 Beijing China 2. Department of Mathematics Queens College City University of New York 11367 NY USA 3. Department of Mathematics Graduate School City University of New York 10016 New York NY USA 4. Academy of Mathematics and Systems Science Chinese Academy of Sciences 100080 Beijing China

We study a conformal measure for an infinitely renormalizable quadratic polynomial. We prove that the conformal measure is ergodic if the polynomial is unbranched and has complex bounds. The main technique we use in t... 详细信息

关键词： Julia set, conformal measure, three-dimensional puzzle, infinitely renormalizable quadratic polynomial.

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth Sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2., WU Qingbai2.& WANG Yibo3.1. Institute of Mountain Hazards and Environment, {2. Academy of Sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research Institute, {2. Academy of Sciences, Lanzhou 73.000, china 3. Resource and Environment School, Lanzhou university, Lanzhou 73.000, china 1. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 2..11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

Two possible mechanisms for vortex self-organization

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Science china Earth Sciences 2006年第2期49卷 202-211页

作者： LUO Zhexian2. ZHOU Xiuji1 & GAO Shouting3.1. chinese Academy of Meteorological Sciences, Beijing 100081, {2. 2. Department of Space Information Science, Nanjing university of Information Science and Technology, Nanjing 2.0044, {2. 3. Institute of Atmospheric Physics, chinese Academy of Sciences, Beijing 10002., {2. 2. Department of Environmental Science Nanjing University of Information Science and Technology Nanjing 210044 China 1. chinese Academy of Meteorological Sciences Beijing 100081 China 3. Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The vortex self-organization is investigated in this paper by four groups of numerical experiments within the framework of quasi-geostrophic model, and based on the experimental results two types of possible mechanisms for vortex self-organization are suggested. The meso-scale to-pography may enable separated vortices to merge into a larger scale vortex; and the interaction of meso-γ and meso-β scale systems may make separated vortices to self organize a typhoon-like vor-tex circulation.

关键词： vortex, self-organization, meso-scale topography, interaction of different scales.

SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications

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Science china Earth Sciences 2006年第10期49卷 1032-1042页

作者： PENG Touping1,2. WANG Yuejun1, FAN Weiming1, LIU Dunyi3. SHI Yuruo3.& MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, {2. Academy of Sciences, Guangzhou 510640, china 2. graduate {3. of {2. Academy of Sciences, Beijing 10003., china 3. SHRIMP isotope Laboratory, {2. Academy of Geological Sciences, Beijing 10003., china 4. Institute of Geology and Geophysics, {2. Academy of Sciences, Beijing 10002., china Key Laboratory of Isotope Geochronology and Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China graduate university of {2. Academy of Sciences Beijing China SHRIMP isotope Laboratory Chinese Academy of Geological Sciences Beijing China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China

The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02.X-13.) and southern (2.JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 2.6Pb/2.0}U ages of 2.9.4 ± 3.0 Ma and 2.0}.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02.X-95) from the Manghuai Formation give a weighted mean 2.6Pb/2.0}U age of 2.0}.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~2.0} Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 2.6Pb/2.0}U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province.

关键词： SHRIMP zircon U-Pb dating, Middle Triassic, Lincang granitic batholith, Manghuai Formation rhyolite, southern Lancangjiang.