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Remote sensing based shrub above-ground biomass and carbon storage mapping in Mu Us desert,china

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Science china(Technological Sciences) 2010年第S1期53卷 176-183页

作者： XU Min 1.2,CAO ChunXiang 1.TONG QingXi 1.{3. ZengYuan 3.ZHANG Hao 1.HE QiSheng 1.2,GAO MengXu 1.2,{1. Jian 1.2,ZHENG Sheng 1.2,CHEN Wei 1.2.& ZHENG LanFen 1.1.tate Key Laboratory of Remote Sensing Science,Jointly Sponsored by the institute of Remote Sensing App{3.cations of chinese academy of Sciences and beijing Normal University,beijing 1.01.1.{23. 2 Graduate School of the chinese academy of Sciences,beijing 1.0049,{23. 3.Research institute of Forest Resources and Information Techniques,chinese academy of Forestry,beijing 1.009,{23. State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing China Graduate School of the chinese {1. of Sciences Beijing China Research institute of Forest Resources and Information Techniques Chinese Academy of Forestry Beijing China

The estimation of above-ground biomass(AGB) and carbon storage is very important for arid and semi-arid ***-1./B satellite data combined with field measurement data was used for the estimation of shrub AGB and carbon storage in the Mu Us desert,*** correlations of shrub AGB and spectral reflectance of four bands as well as their combined vegetation indexes were respectively analyzed and stepwise regression analysis was employed to establish AGB prediction *** prediction equation based on ratio vegetation index(RVI)was proved to be more suitable for shrub AGB estimation in the Mu Us desert than *** AGB and carbon storage were mapped using the RVI based prediction model in *** statistics showed the western Mu Us desert has relatively high AGB and carbon storage,and that the gross shrub carton storage in Mu Us desert reaches 1. 799 2.0 t,which has greatly contributed to the carbon fixation in northern china.

关键词： above-ground biomass carbon storage Mu Us desert HJ-1./B remote sensing

Size-dependent hydroxyl radicals generation induced by SiO_2.ultra-fine particles: The role of surface iron

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Science china Chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1. ZHU Tong1. {2. Yi1.{1. zhao JinCai3.1.College of Environmental Sciences and Engineering, Peking University, beijing 1.0871. china 2.chinese {12. of Meteorological Sciences, beijing 1.0871. china 3.institute of Chemistry, chinese {12. of Sciences, beijing 1.0871. china College of Environmental Sciences and Engineering Peking University Beijing China chinese {1. of Meteorological Sciences Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM1.). The ultra-fine fraction of PM1. has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capabi{2.ty of dif-ferent sizes of SiO2.particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2.particles with diameters of 1., 1.0, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 1. nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2.= 0.81., p1.. Washed particles, with their surface iron being removed, did not generate ·OH. The iron-containing leachate from these washings was able to enhance ·OH production as untreated particles did. Therefore, the presence of adsorbed iron on the surface of the SiO2.particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2.acted as an inert substrate, and the surface of ultra-fine SiO2.particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

Petrogenesis and dating of the Kangding complex,Sichuan Province

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Science china Earth Sciences 2005年第5期48卷 622-634页

作者： CHEN Yuelong 1 , LUO zhaohua 1 , zhao Junxiang, {2. Zhihong, ZHANG Hongfei & SONG Biao 3.1. Faculty of Earth Sciences and Natural Resources, {3. University of Geosciences, beijing 100083. {3. 2. Faculty of Earth Sciences, {3. University of Geosciences, Wuhan 43.074, {3. 3. beijing SHRIMP Center, institute of Geology, chinese academy of Geological Sciences, beijing 10003., {3. Faculty of Earth Sciences and Natural Resources China University of Geosciences Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China beijing SHRIMP Center Institute of Geology Chinese Academy of Geological Sciences Beijing China

An analysis of major and trace element geochemistry and SHRIMP U-Pb zircon dating of mafic, intermediate, and felsic rocks from the Mianning metamorphic complex of Si- chuan Province was conducted. One of our conclusions is that a majority of the zircons crystal- lized between 72.1}and 773.Ma in a magmatic regime. The complexes contain early to late Pa- leo-proterozoic relict zircons from ancient continental crust. The oldest age, 2.68 Ma, may rep- resent the basement of the Yangtze block. Overgrowth zircon rims and palingenetic zircons have been observed and dated, and are believed to have formed after crystallization, during Paleozoic and Mesozoic metamorphic-anatexis. We also conclude that depletion of Nb, Ta, HREE, in a spider-diagram normalized to primitive mantle and calc-alkaline association, implies that they formed in island-arc or under-plating settings.

关键词： Kangding complex, zircons, SHRIMP, tectonic setting.

Timing and history of marine hydrocarbon accumulation in Tarim craton

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chinese Science Bulletin 2002年第S1期47卷 120-127页

作者： zhao Jingzhou~(1.2. & {1. Qiming~3.1. Department of Petroleum Geology, Xi’an Petroleum institute, Xi’an 71.065, china 2. Research institute of Petroleum Exploration and Development, Petrochina, beijing 1.0083. china 3. Tarim Oilfield Company, Kuerle, Xinjiang 841.00, china Department of Petroleum Geology Xi’an Petroleum Institute Xi’an China Research institute of Petroleum Exploration and Development PetroChina Beijing China Tarim Oilfield Company Kuerle Xinjiang China

Based on the analyses of hydrocarbon inclu-sions, K-Ar dating of authigenic illites and oil/gas-watercontact retrospection as well as other methods, the marineprimary reservoirs in the cratonic region of the Tarim Basinare found to have been formed in the late Caledonian toearly Hercynian, late Hercynian, and Himalayan, and oil andgas adjusted and redistributed in the Yanshanian (Jurassic toCretaceous) and Himalayan (Tertiary). The analyses alsoshow that the remaining primary oil accumulations aremostly formed in the late Hercynian, and the secondary oilreservoirs resulted from the adjustment and redistribution ofthe earlier accumulations during the Yanshanian and Hima-layan (especially late Himalayan), of which the Himalayan isalso the major stage of gas accumulation. The primary oilreservoirs formed in the late Hercynian mostly occur withinthe Paleozoic formation, whereas the secondary reservoirsformed in the Himalayan in the Mesozoic. The late adjust-ment and redistribution of reservoirs in the craton region ofthe Tarim Basin is ubiquitous because of the intensified tec-tonic movements since the Mesozoic, especially Cenozoic andintrusion of the high- to over-mature gas. Furthermore, thelower amplitude of reservoirs in the craton region also makesthem easier to be adjusted and redistributed. Therefore, theremaining paleo-uplift and palaeo-slope developed in rela-tively stable tectonic regions are the main potential areas forthe middle-large marine reservoirs in the Tarim Basin.

关键词： Tarim Basin craton geochronology of hydrocarbon accumulation history of hydrocarbon accumulation marine reservoir primary reservoir secondary reservoir.

Characteristics of InGaN multiple quantum well blue-violet laser diodes

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Science china(Technological Sciences) 2006年第6期49卷 727-732页

作者： li Deyao1. ZHANG Shuming1. WANG Jianfeng1. CHEN Jun1. CHEN lianghui2, CHONG Ming2, ZHU Jianjun1. zhao Degang1. liU Zongshun1. YANG Hui1.& liANG Junwu1.1. State Key Laboratory of Integrated Optoelectronics, institute of Semiconductors, chinese academy of Sciences, beijing 1.0083. china 2. Nano-Optoelectronics Laboratory, institute of Semiconductors, chinese academy of Sciences, beijing 1.0083. china State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing China Nano-Optoelectronics Laboratory Institute of Semiconductors Chinese Academy of Sciences Beijing China

Studies on InGaN multiple quantum well blue-violet laser diodes have been reported. Laser structures with long-period multiple quantum wells were grown by metal-organic chemical vapor deposition. Triple-axis X-ray diffraction (TAXRD) measurements show that the multiple quantum wells were high quality. Ridge waveguide laser diodes were fabricated with cleaved facet mirrors. The laser diodes lase at room temperature under a pulsed current. A threshold current density of 3.3.kA/cm[2.; a characteristic temperature T 0 of 1.5 K were observed for the laser diode.

关键词： metalorganic chemical vapor deposition (MOCVD), GaN-based laser diodes, multiple quantum well, ridge waveguide, threshold current.

Theoretical study on the reaction mechanism of(CH_3._3.O+CO

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Science china Chemistry 2005年第1期48卷 18-24页

作者： zhao Hongmei1.2.3. SUN Chengke1.4, ZHANG Rongchang3. XI Hongmin3.& {1. Zonghe1.1. Department of Chemistry, beijing Normal University, beijing 1.0875, china 2. The Laboratory of Molecular Reaction Dynamics, institute of Chemistry, {13. {12. of Sciences, beijing 1.0080, china 3. Department of Chemistry, Beihua University, Ji{1.n 1.2.1., china 4. Department of Chemistry, Qujing Normal University, Yunnan 655000, china Department of Chemistry Beijing Normal University Beijing China The Laboratory of Molecular Reaction Dynamics Institute of Chemistry Chinese Academy of Sciences Beijing China Department of Chemistry Beihua University Jilin China Department of Chemistry Qujing Normal University Yunnan China

The reaction mechanism of (CH3.3.O with CO has been theoretically investigated using density-functional theory (DFT) calculations at B3.YP/6-3.0}* level. In order to get more reliable energy values the single-point energy is evaluated at CCSD (T)/6-3.0}+G** level. The results show that the reaction is multi-channel and the reaction of (CH3.3.O radical with CO mostly produces (CH3.3. + CO{3. The reaction could play a role in eliminating air pollution.

关键词： DFT, B3.YP, (CH3.3.O, radical.

Development of solar-blind AlGaN 1.8x1.8 Ultraviolet Focal Plane Arrays

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Science china(Technological Sciences) 2008年第6期51卷 820-826页

作者： YUAN YongGang1, ZHANG Yan1, CHU KaiHui1, li XiangYang1, zhao DeGang{2. YANG Hui2.1 State Key Laboratories of Transducer Technology, Shanghai institute of Technical Physics, chinese academy of Sciences, Shanghai 2.0083. china 2.institute of Semiconductors, chinese academy of Sciences, {13. 100083. china State Key Laboratories of Transducer Technology Shanghai Institute of Technical Physics Chinese Academy of Sciences Shanghai China institute of Semiconductors Chinese Academy of Sciences Beijing China

This paper reports the development of solar-blind aluminum gallium nitride (AlGaN) {2.8×{2.8 UV Focal Plane Arrays (FPAs). The back-illuminated hybrid FPA archi- tecture consists of an {2.8x{2.8 back-illuminated AlGaN PIN detector array that is bump-mounted to a matching {2.8x{2.8 silicon CMOS readout integrated circuit (ROIC) chip. The {2.8×{2.8 p-i-n photodiode arrays with cuton and cutoff wave-lengths of 2.3.and 2.8 nm, with a sharp reduction in response to UVB (2.0―3.2} nm) light. Several examples of solar-blind images are provided. This solar-blind band FPA has much better application prospect.

关键词： AlGaN photodiode ultraviolet FPA solar-blind

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science china Chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1. YANG limin1. XU Zhi3. {1. Ying2. liNG Xiaofeng3. li Qingbo1. WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1.& WU Jinguang1.1. The State Key Laboratory of Rare Earth Materials and Applications, College of Chemistry and Molecular Engineering, Peking University, beijing 1.0871. china 2. institute of Chemistry, chinese academy of Sciences, beijing 1.0080, china 3. Department of Surgery, Third Hospital, Peking University, beijing 1.0083. china 4. Department of Oncology Surgery, the First Hospital of Xi’an Jiaotong University, Xi’an 71.061. china Correspondence should be addressed to Wu Jinguang (email: wujg@***) The State Key Laboratory of Rare Earth Materials and Applications College of Chemistry and Molecular Engineering Peking University Beijing China Department of Surgery Third Hospital Peking University Beijing China institute of Chemistry Chinese Academy of Sciences Beijing China Department of Oncology Surgery the First Hospital of Xi’an Jiaotong University Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3.0}normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near {2.45 cm-{2. a shift of the amide I band to lower wave number, a decrease in the ～{2.50 cm-{2.peak to less than the～{2.00 cm-{2.peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2. which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

Proton induced X-ray emission (PIXE) analysis of sources of porcelain body of Ru Guan and Jun Guan porcelains

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 411-420页

作者： li Guoxia1, zhao Weijuan1, li Rongwu{3. SUN Hongwei1, GUO Min1, WANG Yanfang1, liU Hui1, zhao Qingyun3. SUN Xinmin3. zhao Wenjun3.& CHENG Huansheng4 1. Faculty of Physical Engineering, Zhengzhou University, Zhengzhou 45005{3. china {3. Department of Physics, beijing Normal University, beijing 100875, china 3. {13. of Cultural Relic and Archaeology of Henan Province, Zhengzhou 450000, china 4. {13. of Modern Physics, Fudan University, Shanghai {3.043., china Faculty of Physical Engineering Zhengzhou University Zhengzhou China Department of Physics Beijing Normal University Beijing China institute of Cultural Re{1.c and Archaeology of Henan Province Zhengzhou China institute of Modern Physics Fudan University Shanghai China

3. samples of Ru Guan porcelain body and 50 samples of Jun Guan porcelain body (both kinds being in different body colors) were selected with the purpose of finding out the source of raw materials and their classification relationship so as to search for ways of non-destructive discrimination. Proton induced X-ray emission (PIXE) has been applied to these samples to determine their chemical elements. The data of seven major chemical elements collected from these samples were further studied through fuzzy cluster analysis. Results indicate that the origin of raw materials of Jun Guan porcelain body samples is comparatively more concentrated in certain places, while that of Ru Guan porcelain body samples is scattered about. The places of origin of raw materials of the majority of Ru Guan and Jun Guan porcelain body samples have something in common, but some differences still exist. It might be an important way for non-destructive discrimination among Ru Guan and Jun Guan porcelains by combining PIXE with fuzzy cluster analysis.

关键词： Ru Guan and Jun Guan porcelain, source of porcelain body, PIXE, fuzzy cluster analysis, non-destructive discrimination.