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Mercury isotope constraints on the genesis of late Mesozoic Sb deposits in South china

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Science china Earth Sciences 2022年第2期65卷 269-281页

作者： changzhou DENG Jiawei ZHANG Ruizhong HU Kai LUO Yanan ZHU Runsheng YIN State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China Guizhou Geological Survey Bureau of Geology and Mineral Exploration and Development of Guizhou ProvinceGuiyang 550081China technology Innovation Center of Mineral Resources Exploration engineering in Bedrock Zone Ministry of Natural ResourcesGuiyang 550081China college of Resources and Environmental engineering Guizhou UniversityGuiyang 550025China School of Earth Sciences Yunnan UniversityKunming 650500China

The late Mesozoic antimony(Sb)mineralization belt in South china hosts a large portion of the world’s Sb ***,the source and mineralization processes of these Sb deposits remain ***,we measured mercury(Hg)concentrations and isotopic compositions of stibnite in the Banpo Sb-only and Woxi Sbpolymetallic ore deposits,as well as associated rocks in the Yangtze Block in order to constrain the metal sources and ore formation processes in the South china Sb mineralization *** samples from both deposits exhibit significant enrichment in Hg(4.23–50.6 ppm)and have higher δ^(202)Hg values(−0.47‰to 2.03‰)than the studied Precambrian basement rocks(−1.42‰to 0.59‰),Paleozoic sedimentary rocks(−2.40‰to−0.32‰),and other natural Hg reserves(e.g.,marine and continental systems).This indicates that significant mass-dependent fractionation of Hg isotopes occurred during hydrothermal *** to slightly positive Δ^(199)Hg values of−0.17‰to 0.02‰were obtained for stibnite from the studied deposits,similar to values for the Precambrian basement rocks,but different from those of the Paleozoic sedimentary rocks and data previously reported for mantle *** suggests that Precambrian basement rocks were the source of Hg and associated *** data and the tectonic evolution of South china indicate that late Mesozoic asthenospheric upwelling,in response to the Paleo-Pacific oceanic slab foundering,generated heat that drove the circulation of fluids in the basement and crustal basinal *** fluids leached Sb,Hg,and other metals from the Precambrian basement rocks and formed the world-class Sb mineralization belt in South china.

关键词： Hg isotopes Mass-independent fractionation Sb deposits Metamorphic basement South china

Effects of Citral on Aspergillus flavus Spores by Quasi-elastic Light Scattering and Multiplex Microanalysis Techniques

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Acta Biochimica et Biophysica Sinica 2004年第4期36卷 277-283页

作者： Man LUO1,2, Li-Ke JIANG2, Yao-Xiong HUANG3, Ming XIAO4, Bo LI4, and Guo-Lin ZOU1* 1college of Life Sciences, Wuhan University, Wuhan 430072, china 2college of Life Sciences, Anhui Agricultural University, Hefei 230036, china 3 institute of Biomedical engineering, Ji’nan University, Guangzhou 510632, china 4Ministry of Education Key Laboratory for Biodiversity Science and Ecological engineering, the institute of Biodiversity Science, Fudan University, Shanghai 200433, china college of Life Sciences Wuhan UniversityWuhan 430072 China college of Life Sciences Anhui Agricultural UniversityHefei 230036 China institute of Biomedical engineering Ji'nan UniversityGuangzhou 510632 China Ministry of Education Key Laboratory for Biodiversity Science and Ecological engineering the Institute of Biodiversity Science Fudan UniversityShanghai 200433 China

Citral refined from Litsea cubeba oil has been found to have a strong influence on fungi, especially Aspergillus flavus. Multiplex microanalysis and quasi-elastic light scattering techniques were applied to study the effects of citral on Aspergillus flavus spores from the levels of membrane, organelle and intracellular macromolecule. It was found that citral injured the wall and the membrane of A. flavus spore, resulting in decrease of its elasticity. After entering the cell, citral not only influenced the genetic expression of mitochondrion reduplication and its morphology, but also changed the aggregation of protein-like macromolecules. As a result, cells, organelles and macromolecules lost their normal structures and functions, eventually leading to the loss of germination ability of A. flavus spores. Since Litsea cubeba oil as food additive and antifungal agent is safe and less poisonous, it is important to elucidate the inhibitory mechanisms of Litsea cubeba oil on the germination ability of A. flavus spore.

关键词： citral Aspergillus flavus spore multiplex microanalysis techniques quasi-elastic light scattering technique

A two-dimensional study on natural convection and heat transfer in the enclosure with heat transfer and radiation coupled in natural convection

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Science china(Technological Sciences) 2010年第4期53卷 991-999页

作者： ZHAN NaiYan1,2,YANG Mo1 & XU PeiWei2 1 college of Power engineering,University of Shanghai for Science and technology,Shanghiai 200093,china 2 Department of Environmental engineering,Jilin Architectural and Civil engineering institute,Changchun 130021,china 1. college of Power engineering University of Shanghai for Science and Technology Shanghiai 200093 China2. Department of Environmental Engineering Jilin Architectural and Civil Engineering Institute Changchun 130021 China

Numerical investigation using SIMPLE algorithm with QUICK scheme for natural convection and heat transfer in the enclosure bounded by a solid wall and with heat transfer and radiation coupled in natural convection has been *** various parameters are:Rayleigh number(from 103 to 105),dimensionless conductivity of bounding wall(from 0 to 100),dimensionless wall thickness(from 0 to 0.6) and radiation emissivity of all surfaces(from 0 to 1).The results suggest that flow and heat transfer are influenced by *** is a dominant action on flow and heat *** increase of the thermal conductivity of wall,flow and heat transfer turn *** temperature distribution changes *** the thermal conductivity of wall is over a certain critical number,the increasing trend of flow and heat transfer may *** increase of enclosure wall thickness,flow and heat transfer turn *** the enclosure wall thickness is over a certain critical number,the flow and heat transfer will turn slow.

关键词： conduction natural convection radiation couple numerical simulation

Multiparty simultaneous quantum identity authentication with secret sharing

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Science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3 & ZHANG Xing4,5 1 college of Computer Science and technology,Beijing University of technology,Beijing 100022,china 2 State Key Laboratory of Information Security (Graduate University of the Chinese Academy of Sciences),Beijing 100049,china 3 School of Science,Beijing University of Posts and Telecommunications,Beijing 100876,china 4 institute of Electronic technology,Information engineering University,Zhengzhou 450004,china 5 Trusted Computing Laboratory,Beijing University of technology,Beijing 100022,china college of Computer Science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate University of the Chinese Academy of Sciences] Beijing 100049 China School of Science Beijing University of Posts Telecommunications Beijing 100876 China institute of Electronic technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Construction and characterization of the transformation-competent artificial chromosome (TAC) libraries of Leymus multicaulis

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Science china(Life Sciences) 2008年第7期51卷 604-613页

作者： XU YueYu 1,2,3,ZHOU YuLei 4,5 ,SONG LinLin 6 ,ZHANG Yan 3 &ZHAO MaoLin 1 1 Beijing Agro-Biotechnology Research Center,Beijing Academy of Agriculture and Forestry Science,Beijing 100097,china 2 Department of Chemistry and Chemical engineering,Hunan institute of engineering,Xiangtan 411104,china 3 college of Life Science,Capital Normal University,Beijing 100037,china 4 college of Life Science,Zhongkai University of Agriculture and technology,Guangzhou 510225,china 5 college of Grassland Science,Gansu Agricultural University,Lanzhou 730070,china 6 Department of Biology,Henan institute of Science and technology,Xinxiang 453003,china 1. Beijing Agro-Biotechnology Research Center Beijing Academy of Agriculture and Forestry Science Beijing 100097 China 2. Department of Chemistry and Chemical engineering Hunan Institute of Engineering Xiangtan 411104 China 3. college of Life Science Capital Normal University Beijing 100037 China 4. college of Life Science Zhongkai University of Agriculture and Technology Guangzhou 510225 China 5. college of Grassland Science Gansu Agricultural University Lanzhou 730070 China 6. Department of Biology Henan Institute of Science and Technology Xinxiang 453003 China

Transformation-competent artificial chromosome system is able to clone and transfer genes efficiently in *** order to clone genes highly tolerant to barley yellow dwarf virus(BYDV),Aphids,drought and salt from Leymus multicaulis,the two TAC genomic libraries I and II were constructed in vector pYLTAC17 and pYLTAC747H/sacB,which contain about 165000 and 236000 recombinant clones *** genome coverage of the two libraries was totally estimated to be about 3―5 haploid genome equivalents,as size selection of genomic DNA fragments was approximately from 9 to 300 *** of the genomic libraries were collected as bulked pools each containing 500 clones or so,stored in twelve 96-deep-well plates and then were gridding in triplicate onto a high-density colony hybridization filter with a 3×3 pattern using a GeneTAC?G3 arraying robot after being transferred manually into three 384-well *** 2501 and 2890 clones of Library in pYLTAC17 and in pYLTAC747H/sacB were stored individually in fourteen 384-well plates and then were automatically gridding in duplicate onto a high-density colony hybridization filter with a 6×6 pattern after a replication of *** positive clones were detected by using the probe glutahione reductase gene of *** libraries constructed here can be used to isolate genomic clones containing target genes,and to carry out genome walking for positional *** the target TAC clones were isolated,they could be immediately transferred into plant genomes with the Agrobacterium system.

关键词： Leymus multicaulis megabase-size DNA transformation-competent artificial chromosome(TAC) genomic library

STUDY ON THE MORPHOLOGY OF POLYVINYL CHLORIDE/POLYSTYRENE BLENDS BY ELECTRON MICROPROBE ANALYSIS

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Chinese Journal of Polymer Science 2000年第5期18卷 437-441页

作者： Zheng-ping Fang Gen-lin Wang Guo-ping Cai Cheng-wei Xu Jie Qian institute of Polymer Composites, Zhejiang University, Hangzhou 310027, china college of Chemical engineering, Zhejiang University of technology, Hangzhou 310014, china Zhejiang Univ Inst Polymer Composites Hangzhou 310027 Peoples R China Zhejiang Univ Technol Coll Chem Engn Hangzhou 310014 Peoples R China

The morphology of polyvinyl chloride/polystyrene (PVC/PS) blend samples with different mass ratios, prepared by means of solution casting and melt mixing, have been successfully examined by electron microprobe analysis (EMP). This experiment was performed in a scanning electron microscope attached to an energy dispersive X-ray analyzer. Differential scanning calorimetry was also used to investigate the phase separation of the blends. The results show that PVC and PS are incompatible and the blends have sea-islands phase structures. Blends prepared via melt mixing have finer phase-dispersion than those prepared via solution casting.

关键词： electron microprobe analysis polyvinyl chloride/polystyrene blends morphology

Effect and mechanism of stresses on rock permeability at different scales

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Science china Earth Sciences 2006年第7期49卷 714-723页

作者： YIN Shangxian1 & WANG Shangxu2 1. Safety engineering college, North china institute of Science and technology, Yanjiao, Beijing 101601, china 2. Key Laboratory of Geophysics Exploration, china University of Petroleum, Beijing 100083, china 1. Safety engineering college North China Institute of Science and Technology Yanjiao Beijing 101601 China 2. Key Laboratory of Geophysics Exploration China University of Petroleum Beijing 100083 China

The effect of geo-stress fields on macroscopic hydro-geological conditions or micro-cosmic permeability of water-bearing media should follow some laws or principles. Cases study and tests show that: (1) At macro-geologic large scale, deformed and crashed rocks which were induced by geo-stress fields changing provided space for groundwater storage and flow. Groundwater adjusts water-bearing space and dilatants fractures by flowing and press transferring. Coupling of liquid and solid can be implemented for rocks and groundwater. Although tectonic fields witness several times of change and build-up in geological time, stress fields forming regional tectonic framework are coherent with seepage fields, orientation of the maximum horizontal stress demonstrates main seepage direc-tions. (2) At macro-geologic middle scale, zones of stresses changing sharply, quite low stresses, stress or shear concentration can be used to show locations and types of main fractures, zones of geo-stresses changing equably can be acted as normal base media zones of tri-porosity media. (3) At micro-geologic small scale, tri-porosity media include fractured rocks, porous rocks and capillary rocks. Investigations indicate that porosity or permeability is functions of effective stresses, and po-rosity or permeability changing rules of porous rocks with variation of effective stresses can be de-scribed as the index model, the model of power exponent functions is suitable for those of fractured rocks, the model of the second power parabola for capillary rocks. The porosity and permeability loss in fractured rocks, which are greater than that in porous rocks, are shown by calculation of effective compressive coefficient and closing pressure in cracks. The calculations can also explain the mecha-nism why porosity changes are always larger than permeability changes. It is proved by the thick wall cylinder theory that the second power parabola relation between porosity or permeability loss and effective

关键词： geo-stress fields, seepage fields, tri-porosity media, effective stresses, permeability, porosity,scale.

Survival probability and ruin probability of a risk model

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Applied Mathematics(A Journal of Chinese Universities) 2008年第3期23卷 256-264页

作者： LUO Jian-hua college of Science,Central South University of Forestry and technology,Changsha 410004,china institute of Statistics,Central South University of Forestry and technology,Changsha 410004,china. college of Science Central South University of Forestry and Technology Changsha 410004 China institute of Statistics Central South University of Forestry and Technology Changsha 410004 China

In this paper, a new risk model is studied in which the rate of premium income is regarded as a random variable, the arrival of insurance policies is a Poisson process and the process of claim occurring is p-thinning process. The integral representations of the survival probability are gotten. The explicit formula of the survival probability on the infinite interval is obtained in the special casc cxponential *** Lundberg inequality and the common formula of the ruin probability are gotten in terms of some techniques from martingale theory.

关键词： risk model thinning process survival probability martingale ruin probability integral representation

On Strategy of "Harmonious Marketing" in Modern Enterprises

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On Strategy of "Harmonious Marketing" in Modern Enterprises