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Journal of Pharmaceutical Analysis 2010年第3期22卷 183-187页

作者： Fei-Long Sun1,2,Min Jin3.Zhi-Gang Qiu3.Zhi-Qiang Shen3.Xin-Wei Wang3.Jun-Wen Li3..school of Life Science and technology,Xi’an Jiaotong University,Xi’an 710049 2.school of {3.al and chemical engineering,Xi’an Polytechnic University,Xi’an 710048 3.institute of {3. and Health,Tianjin 3.0050,china school of Life Science and technology Xi'an Jiaotong University Xi'an 710049 China school of environmental and chemical {3. Xi'an Polytechnic University Xi'an 710048 China institute of environment and Health Tianjin 300050 China

Objective To construct reference standards for detection and quantification of Klebsiella pneumoniae(***)with SYBR Green I-based real-time PCR *** Primers were designed based on the published sequence of the phoE gene of *** standard was prepared by cell culture,PCR and T-A clone methods,and was identified by colony PCR and DNA *** The standard curve showed a very good linear negative regression between threshold cycle(Ct)and Log starting quantity of copy *** detection range was from 5.2 to 5.2×106 copies per reaction,and the detection limit was 6 copies per *** coefficients of variance(CVs)of three parallel experiments were in the range of 0.05%-0.91%.Conclusion The reference standards have high stability and *** can be used in the quantitative detection of ***.

关键词： cloning vector Klebsiella pneumoniae real-time PCR standard

Theoretical study of ZnO adsorption and bonding on Al_2O_3.0001) surface

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Science china(Physics,Mechanics & Astronomy) 2004年第6期47卷 664-675页

作者： LI Yanrong1,YANG Chun1,2,XUE Weidong1,LI Jinshan3.& LIU Yonghua3.1.institute of Microelectronics and Solid State Electronics,University of Electronic Science and Technol- ogy of china,Chengdu 610054,china 2.institute of Mathematics and Software Science,Sichuan Normal University,Chengdu 610068,china 3.institute of chemical Materials,china Academy of engineering Physics,Mianyang 621000,china institute of Microelectronics and Solid State Electronics University of Electronic Science and Technology of China Chengdu 610054 China institute of Mathematics and Software Science Sichuan Normal University Chengdu 610068 China institute of chemical Materials China Academy of Engineering Physics Mianyang 621000 China

ZnO adsorption on sapphire (0001) surface is theoretically calculated by using a plane wave ultrasoft pseudo-potential method based on ab initio molecular dynamics. The results reveal that the surface relaxation in the first layer Al-O is reduced, even eliminated after the surface adsorption of ZnO, and the chemical bonding energy is 43..3.±3..6) kJ·mol?1. The chemical bond of ZnO (0.185 ± 0.01 nm) has a 3.° angle away from the adjacent Al-O bond, and the stable chemical adsorption position of the Zn is deflected from the surface O-hexagonal symmetry with an angle of about 3.°. The analysis of the atomic populations, density of state and bonding electronic density before and after the adsorption indicates that the chemical bond formed by the O2 of the ZnO ? and the surface Al3. has a strong ionic bonding characteristic, while the chemical bond formed by the Zn2+ and the surface O2 has an obvious covalent characteristic, which ? comes mainly from the hybridization of the Zn 4s and the O 2p and partially from that of the Zn 3. and the O 2p.

关键词： α-Al2O3.(0001) ZnO ab initio molecular dynamics chemical adsorption density of states

Preparation of a Novel Micro/nano Tubes via Electrospun Fiber as a Template

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Journal of Materials Science & technology 2004年第5期20卷 613-616页

作者： Taiqi LIUschool of Materials and chemical engineering, Beijing {3. of Petro-chemical technology, Beijing 102617, china Sch. of Mat. and Chem. Eng. Beijing Inst. of Petrochem. Technol. Beijing 102617 China

Poly (para-xylylene) hollow fibers with inner diameters can be prepared via template fibers electrospun from solutions. The PPX is deposited from the vapor phase and the template fiber is selectively removed by heat treatment or solvent extraction. The PPX is partially crystalline and the crystal modification depending on the route is used to extract the template fiber. The thermal stability of the hollow fibers is only slightly reduced relative to the bulk material and the same holds for the UV-stability.

关键词： Electrospinning Fiber chemical vapor deposition Physical vapor deposition Crystal Conductivity

Land Use of the Three Gorges Reservoir Area and the Effect on Its Landscape Pattern in the Recent 50 Years

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 910-914页

作者： HUANG Zhiqin 1,2,3., ZHOU Wancun 1 ,ZHOU Jieming 4 , ZHU Mingcang 3.5 1. institute of Mountain Hazards and environment, Chinese Academy of Sciences , Chengdu 610041, Sichuan, china 2. Graduate University of Chinese Academy of Sciences, Beijing 100049, china 3. Sichuan institute of Land Resource Management, Chengdu 610041, Sichuan , china 4. Department of Resources and environment Science, Sichuan Normal University , Chengdu 610061, Sichuan, china 5. College of Information engineering, Chengdu University of technology, Chengdu 610059, Sichuan, china institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu Sichuan China Graduate University of Chinese Academy of Sciences Beijing China Sichuan institute of Land Resource Management Chengdu Sichuan China Department of Resources and environment Science Sichuan Normal University Chengdu Sichuan China College of Information engineering Chengdu University of Technology Chengdu Sichuan China

The paper makes detailed analysis on the changing processes of the main types of land use in Three Gorges Reservoir Area through the techniques of RS （Remote Sense） and GIS （Geography Information System）. Based on the theory of landscape ecology, many types of landscape pattern indexes are calculated and made correlation analysis. The results indicate that： in 1995 the ecological environment of Three Gorges Reservoir Area was the most vulnerable in the recent 50 years, but resumed in 2002; the landscape pattern diversity index, fractal dimension index and fragmentation index has close correlation with the area of land use/cover change （LUCC）. The research also releases that the increase of the cultivated land, grassland and construction land deteriorates the landscape ecological pattern, while the increase of forest land area will help restore the landscape ecological pattern to its original state. The rapid change of grassland is an important index of the change of landscape pattern, because it has the most effect on change of landscape pattern index.

关键词： the Three Gorges Reservoir Area land use/cover change landscape pattern.

The pilot test of Pt-Pd and Pt-Rh feeds extracted and separated with a new sulfoxide extractant

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Rare Metals 2006年第2期25卷 99-105页

作者： ZHU Ping GU Guobang QU Zhiping HUANG Yanfei YAO Wenxue College of environment Science and engineering Shanghai University Shanghai 200072 China Department of Applied Chemistry South China University of Technology Guangzhou 510640 China institute of Material Reutilization of the Ministry of Internal Trade. Xuzhou 221006. china

Platinum, palladium and rhodium of the raw feeds extracted and separated with a new sulfoxide extractant （MSO） were studied in the paper. The pilot test results showed that the percentage extractions are more than 99% for platinum and palladium in Pt-Pd feed, and the percentage strippings are 100% and 99.2% with HCl and ammonia, respectively. The ratio of palladium to platinum is 0.0016 in stripping platinum solution, and the ratio of platinum to palladium is 0.0020 in stripping palladium solution. The percentage extraction of platinum is 99% in Pt-Rh feed, and the percentage stripping is 100%. The ratio of rhodium to platinum is 0.0002 in stripping platinum solution. Therefore, platinum, palladium, and rhodium feeds are separated effectively with MSO.

关键词： solvent extraction pilot test sulfoxide platinum group metals

Oxidative Debenzylation and Acetylation of Hexabenzylhexaazaisowutzitane

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含能材料 2002年第2期10卷 66-68页

作者： PANG Si-ping, Yü Yong-zhong, ZHAO Xin-qi (school of chemical engineering and Material Science, Beijing {3. of technology, Beijing 100081, china) school of chemical engineering and Material Science Beijing Institute of Technology 北京 100081

The oxidative reactivity of hexabenzylhexaazaisowutzitane(HBIW)under different conditions was studied. It was found that the N-benzyl groups were found to form benzoyl group after oxidation. They might also be first d... 详细信息

关键词：氧化乙酰化炸药 HBIW 苯甲基

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science china Earth Sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2, KANG Shichang2,3.5, SUN Junying4,5, Paul A. Mayewski2 & QIN Dahe5 1. National Climate Center, china Meteorological Administration, Beijing 100081, china 2. Climate Change {3., University of Maine, Orono, ME 04469, USA 3. {3. of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100085, china 4. Chinese Academy of Meteorological Sciences, Beijing 100081, china 5. Key Laboratory of Ice Core and Cold Regions environment, Cold and Arid environmental and engineering Research {3., Chinese Academy of Sciences, Lanzhou 73.000, china 1. National Climate Center China Meteorological Administration 100081 Beijing China 2. Climate Change institute University of Maine 04469 Orono ME USA 3. institute of Tibetan Plateau Research Chinese Academy of Sciences 100085 Beijing China 4. Key Laboratory of Ice Core and Cold Regions environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences 730000 Lanzhou China 5. Chinese Academy of Meteorological Sciences 100081 Beijing China

Atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 20D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 20D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (20D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Main chemical ingredients of the celadon glaze from Qingliangsi kiln and Zhanggongxiang kiln

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 487-495页

作者： ZHAO Weijuan1, LU Xiaoke1, LI Guoxia1, GUO Min1, XIE Jianzhong1, GAO Zhengyao1, SUN Xinmin2, GUO Musen2, CHENG Huansheng3.& ZHANG Bin3.1. Faculty of Physical engineering, Zhengzhou University, Zhengzhou 450052, china 2. Research institute of Cultural Relic and Archaeology, Henan Province, Zhengzhou 450004, china 3. Research institute of Modern Physics, Fudan University, Shanghai 20043., china 1. Faculty of Physical engineering Zhengzhou University Zhengzhou 450052 China 2. Research institute of Cultural Relic and Archaeology Henan Province Zhengzhou 450004 China 3. Research institute of Modern Physics Fudan University Shanghai 200433 China

The proton induced X-ray emission (PIXE) is used to determine the chemical ingredients of seven main elements in the samples of Ru Guan porcelain glazes and Ru Civil porcelain from Qingliangsi kiln in Baofeng County and the samples of celadon glaze from Zhanggongxiang kiln in Ruzhou City. The PIXE data are then analyzed by scatter analysis and fuzzy cluster method for determining their classification and provenance. The results show that there are obvious differences between the ingredients of glaze material of Ru Guan porcelain and Ru Civil porcelain from Qingliangsi kiln, of which the former ingredients are stable and its source is localized, and that the sources and ingredients of the glaze of Ru Guan porcelain and those of celadon glaze from Zhanggongxiang kiln are not wholly the same, of which the latter sources are much scattering.

关键词： Zhanggongxiang kiln, Qingliangsi kiln, the source of raw material, the proton induced X-ray emission.

Resolution of α-cyclohexyl-mandelic acid enantiomers by two-phase (O/W) recognition chiral extraction

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Science china Chemistry 2007年第6期50卷 764-769页

作者： TANG KeWen1,2, ZHANG GuoLi2, HUANG KeLong2, LI Yuanjian3.& YI JianMin1,2 1 Department of Chemistry and chemical engineering, Hunan institute of Science and {3., Yueyang 414000, china 2 College of Chemistry and chemical engineering, Central South University, Changsha 410083. china 3.College of Pharmaceutical Science, Central South University, Changsha 410078, china Department of Chemistry and chemical engineering Hunan Institute of Science and TechnologyYueyang 414000China College of Chemistry and chemical engineering Central South UniversityChangsha 410083China

This paper presents a new chiral separation technology:two-phase(O/W)recognition chiral *** behavior of alpha-cyclohexyl-mandelic acid enantiomers was studied in the extraction system with D(L)-isobutyl tartrate in 1,2-dichloroethane organic phase and beta-CD derivatives in aqueous phase,and the influence of the kind and concentration of extractant and pH on extraction performance was *** experimental results indicate that two-phase(O/W)recognition chiral extraction is of strong chiral separation ***-^-CD,HE-beta-CD and Me-beta-CD have higher recognition ability for S-CHMA than that for R-CHMA,among which HP-beta-CD has the strongest ability;whereas,D-isobutyl tartrate has reversed recognition ability for *** the extraction system containing HP-beta-CD and D-isobutyl tartrate,e.e.% of S-CHMA in aqueous phase reached 27.6% by one stage extraction,and the distribution ratio for R-CHMA(k_R)and for S-CHMA(k_S)and separation factor(alpha)are 2.44,0.89 and 2.49,***,pH and concentration of extractant have great effects on chiral separation ***-phase(O/W)recognition chiral extraction has great significance for preparative separation of racemic compounds.

关键词： two-phase(W/0)recognition chiral extraction alpha-cyclohexyl-mandelic acid enantiomers

The Influence of Free Water Content on Dielectric Properties of Alkali Active Slag Cement Paste

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Journal of Wuhan University of technology(Materials Science) 2007年第4期22卷 774-777页

作者：李继忠 University of Science and technology Beijing Beijing Urban Construction Group Co. LtdConcrete Branch CompanyBeijing 100039China

The dielectric performance of alkali activated slag （AAS） cement paste was investigated in the frequency range of 1 to 1000 MHz. The experimental results showed the unstable dielectric properties of harden paste were mostly influenced by the fraction of free water in paste or absorbed water from ambient, but not including hydration water and microstructure. The free water was completely eliminated by heat treatment at 105 ℃ about 4 hours, and then its dielectric loss was depressed; but with the exposure time in air increasing, the free water adsorption in ambient air made the dielectric property of harden cement paste to be bad. The temperature and relative humidity of environment was the key factors of free water adsorption; hence, if the influence of free water on dielectric constant was measured or eliminated, the cement-based materials may be applied in humidity sensitive materials or dielectric materials domains.

关键词： alkali activated slag cement (AASC) dielectric constant dielectric loss relative humidity free water adsorption