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Status of study on biological and toxicological effects of nanoscale materials

Science China chemistry 2005年第5期48卷 385-394页

作者： WANG Bing1, FENG Weiyue1, ZHAO Yuliang1, XING Gengmei1, CHAI Zhifang1, WANG Haifang2.& JIA Guang3 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab), Institute of High Energy Physics, Chi-nese Academy of Sciences, beijing 100049, China 2. College of chemistry and Molecular Engineering, Peking University,{2., China 3. department of Occupational and Environmental Health Sciences, School of Public Health, Peking University, beijing 100083, China 1. Laboratory for Bio-Environmental Health Sciences of Nanoscale Materials (Nanosafety Lab) Institute of High Energy Physics Chinese Academy of Sciences 100049 Beijing China 2. College of chemistry and Molecular Engineering Peking University 100871 Beijing China 3. department of Occupational and Environmental Health Sciences School of Public Health Peking University 100083 Beijing China

Because the physical and chemical properties of nanosized materials mostly differ from the existing microsized materials, their potential impacts on human health and the envi-ronment will be topics under the serious discussions in press and in a number of international scientific journals. We analyze and summarize the existing data of the experimental study on the biological activities and adverse effects of nanoscale materials/particles including single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron powders. Though some biological behaviors of nanoscale materials observed cannot be understood on the basis of the current knowledge, as the existing data are mostly preliminary, it is too early to make some ex-clusive conclusions on biological activities (or the toxicity) of any of nanoscale materials. The experimental techniques, the current topics, and the future research directions for this new re-search field are also discussed.

关键词： nanomaterials, single wall carbon nanotubes, multi wall carbon nanotubes, titanium oxide and iron, biological activity and toxicological effect.

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Inhibitory effect of picroside Ⅱ on hepatocyte apoptosis

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Acta Pharmacologica Sinica 2005年第6期26卷 729-736页

作者： Hua GAO, Ya-wei ZHOU~2.College of chemistry and Molecular Engineering, Peking University, beijing 100871, China College of chemistry and Molecular Engineering Peking University Beijing China

Aim: To investigate the influence of picroside on hepatocyte apoptosis and its mechanism. Methods: Morphological changes and quantification of apoptotic cells were determined under transmission electron microscopy and flow cytometry respectively. DNA fragmentation was visualized by agarose gel electrophoresis. Semi-quantitative reverse transcription-PCR (RT-PCR) was used to analyze the expression of bcl-2.and bax genes. The content of manganese-superoxide dismutase (SOD) in liver mitochondria was detected by the Marland method. The content of malonic aldehyde (MDA) and the protein level in liver tissue were determined by thiobarbituric acid colorimetry and Lowry method. Results: Picroside decreased the levels of alanine aminotransferase and aspartate aminotransferase in the serum resulting from acute-liver injured mice induced with D-GalN and LPS; it also reduced the content of MDA, and thus, enhanced the activity of SOD. Picroside 0 mg/kg was found to protect hepatocytes against apoptosis in a dose-dependent manner; it up-regulated the expression of bcl-2.genes, thus increased the bcl-2.bax ratio. Conclusion: Picroside 鈪an protect hepatocytes against injury and prevent hepatocytes from apoptosis. It might by upregulating the bcl-2.gene expression and antioxidation.

关键词： picroside Ⅱ hepatocytes apoptosis oxidative stress bcl-2.genes bax genes

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Syntheses,characterization,crystal structure and magnetic properties of copper(Ⅱ) α,β-unsaturated carboxylate complexes with trimethyl phosphate

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Chinese Science Bulletin 2001年第12期46卷 987-991页

作者： WANG Yaoyu, LIU Ping, SHI Qian, GAO Yici & SHI Qizhen1. department of chemistry, Northwest University, Xi’an 710069, China {2., Wenzhou Teachers College, Wenzhou 32.003, China 3. department of chemistry, Lanzhou University, Lanzhou 730000, China department of chemistry Northwest University Xi’an China department of chemistry Wenzhou Teachers College Wenzhou China department of chemistry Lanzhou University Lanzhou China

Two ternary complexes Cu2.4[OP(OCH3)3]2.(A represents CH2.CH-COO- and CH2.C(CH3)-COO-) have been synthesized, and elemental analyses, IR, ESR, electronic reflectance spectra and magnetic studies were carried out. The single crystal X-ray diffraction shows that Cu2.CH2.C(CH3)-COO]4[OP(OCH3)3]2.is triclinic, with space group P1, a = 1.0512.(13), b = 1.7559(5), c = 1.94479(3) nm, α =91.2.3(14)°,(β = 102.559(6)°,γ= 106.339(13)°, Z = 4 and R = 0.0668. Two copper(Ⅱ) atoms are bridged by four (a-methacrylate groups, and each copper(Ⅱ) atom is coordinated with a trimethyl phosphate molecule in the axial position, forming a distorted square pyramidal configuration. The symmetric center is between the two copper(Ⅱ) atoms, and the Cu-Cu bond distance is 0.2.098(6) nm. The Cu-Cu distance and magnetic studies suggest that there exist anti-ferromagnetic interactions between the two copper(Ⅱ) atoms.

关键词： copper(Ⅱ ) complex α β-unsaturated carboxylate trimethyl phosphate magnetic property crystal structure.

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Application of ERS-1 scatterometer data to studying land surfaces ──Distributive characteristic of backscattering coefficient over China land surfaces

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Chinese Science Bulletin 1998年第23期43卷 1950-1955页

作者： WANG Xiangyun 1, WANG Chao 2. GUO Huadong 2.and SHI Yangshen 1 1. department of Earth Sciences, Nanjing University, Nanjing 2.0093, China 2. Institute of Remote Sensing Applications, Chinese Academy of Sciences, beijing 100101, China department of Earth Sciences Nanjing University Nanjing 210093 China Inst. of Remote Sensing Applications Chinese Academy of Sciences Beijing 100101 China

ERS 1 WSC data were obtained by international cooperation. The distributive characteristics of radar backscattering coefficient image of China land surface are analyzed and the research results are presented. The capability of ERS 1 WSC data for monitoring land surfaces is investigated. The results show that the radar backscattering coefficient images can reveal the natural landform features of China land. Using the WSC data can discriminate six types of major land coverage, including evergreen vegetation and snow covered region, vegetation and crops, mountains, grassland, desert and grassland, desert. On the whole, the radar backscattering coefficient image of China land is the synthesis of the vegetation map and terrain map. Statistical study of the typical terrain shows that the radar backscatter coefficients of China land range from -2. dB to -5 dB. The lowest value corresponds to the deserts of Badain Jaran, Takla Makan, and Tengger. The highest value corresponds to snow covered regions of Himalaya Mountains and Tianshan Mountains.

关键词： ERS 1 WSC radar backscattering coefficient land surfaces coverage.

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Preparation and Characterization of Chitosan/Carboxymethylated Konjac Glucomannan Blend Films

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Wuhan University Journal of Natural Sciences 2002年第1期7卷 107-112页

作者： Zheng Hua 1 , Du Yu-min 2.1. department of Chemical Engineering, Wuhan University of Technology, Wuhan 430070, Hubei, China 2. College of chemistry and Molecular Sciences, Wuhan University, Wuhan 430072. Hubei, China Wuhan University of Technology Department of Chemical Engineering Wuhan Hubei China (GRID:grid.162110.5) (ISNI:***) Wuhan University College of Chemistry and Molecular Sciences Wuhan Hubei China (GRID:grid.49470.3e) (ISNI:***)

In order to improve the mechanical and water swelling properties of the chitosan (CS) film, a series of transparent films were prepared by blending 2.(weight) chitosan acetic acid solution with 1.5%(weight) carboxymethylated konjac glucomannan (CMKGM) aqueous solution according to predetermined ratio and drying at 30°C. The morphological structure, miscibility, thermal stability, mechanical properies, and swelling capacity of the blend films were studied by infrared (IR), X-ray diffraction (XRD), differential thermal analysis (DTA), scanning electron micrograph (SEM), and measurements of the mechanical properties and swelling properties. The results demonstrated that there was strong interaction and good miscibility between CS and CMKGM resulted from intermolecular hydrogen bonding and electrostatic force. The mechanical properties in dry state and wet state, thermostability, and water swelling properties of the blend films were obviously improved. The best values of the tensile strength in the dry and wet state achieved 89 MPa and 49 MPa, respectively, when the CMKGM content was 30%(weight). The CS/ CMKGM blend films provided promising biomedical applications.

关键词： Key words chitosan carboxymethylated konjac glucomannan blend films structure characterization

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Recent developments and some open problems in Finsler geometry

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Chinese Science Bulletin 2001年第13期46卷 1059-1061页

作者： MO Xiaohuan & SHEN Zhongmin1. School of Mathematical Sciences, Peking University, beijing 100871, China 2. department of Mathematics, IUPUI 402.N. Blackford Street, Indianapolis, IN 462.2.32.6, USA School of Mathematical Sciences Peking University Beijing China department of Mathematics IUPUI Indianapolis USA

Finsler geometry is just Riemannian geometry without the quadratic restriction. Recent studies on Finsler geometry have taken on a new look. In this article, we will briefly discuss recent developments and some open p... 详细信息

关键词： Finsler geometry open problems recent development.

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Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

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Science China Earth Sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 10002., China 2. department of Atmospheric Science, Yunnan University, Kunming 650091, China 3. Graduate University of the Chinese Academy of Sciences, beijing 100049, China 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. department of Atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the Chinese Academy of Sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

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Effects of elevated CO_2.on growth and carbon partitioning in rice

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Chinese Science Bulletin 1998年第23期43卷 1982-1986页

作者： LIN Weihong\+1 and WANG Dali\+2.1. department of Plant Nutrition, China Agricultural University, beijing 100094, China 2. department of Systems Ecology, Research Center for Eco_Environmental Science, Chinese Academy of Sciences, beijing 100085, China department of Plant Nutrition China Agricultural University Beijing China department of Systems Ecology Research Center for Eco-Environmental Science Chinese Academy of Sciences Beijing China

Rice (\%Oryza sativa\% cv. Jindao 1187) was grown in open_top chambers which contained ambient and enriched CO\-2. CO\-2.elevation stimulated rice tillering during early vegetative stage. However, panicle dry weight per plant did not change at maturity stage. Root biomass was enhanced by high CO\-2. Root / shoot ratio was increased under high CO\-2.at maturity, indicating more carbon allocation to the below_bround part in rice under high CO\-2.

关键词： CO 2 elevation growth carbon partitioning rice (\%Oryza sativa cv\%. Jindao 1187).

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Ecological rebuilding and land reclamation in surface mines in Shanxi Province, China

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Journal of Environmental Sciences 2000年第4期12卷 486-497页

作者： MIAO Ze wei 1, BAI Zhong ke 2. GAO Lin 1 (1. Research Center for Eco Environmental Sciences, Chinese Academy of Sciences, beijing 100085, China E\|mail: miaozewei@*** 2. department of Soil Science, Shanxi Agricultural University Taigu, 03 中科院生态环境研究中心北京 1 0 0 0 85 山西师范大学山西临汾 0 3 0 80 1

It is well known that the mining industry produces a large amount of derelict land, and causes pollution of water loss and soil erosion as well as other environmental damage in China. As land is under pressure in China, it is now policy to restore or reclaim land despoiled by mining, the aim being to develop sustainable and healthy arable land ecosystems. This paper outlines the principles and approaches of ecological restoration, which have been adopted in Shanxi Province with reference to three typical surface mines. In the research, the principles of ecological engineering and ecological succession are considered as the critical theories of ecological restoration in mine degraded land. Meanwhile, the paper made a comparative research on main links of ecological rebuilding in three surface mines in Shanxi Province, which include new land construction, treatment of toxic substances, control of soil erosion, fertility management, irrigation, ecological planning and the establishment of legislation systems. As the research demonstrated, for successful restoration, new land construction is the fundamental framework, but it must be integrated with ecological engineering including ecological planning, the control of soil erosion and vegetation establishment and ecosystem creation in order to optimise land productivity and soil fertility. In addition, the establishment of the legislation systems and organization of administration are also indispensable aspects of ecological rebuilding in mined land.

关键词： ecological restoration land reclamation open-pit mine

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Estimation of annual actual evapotranspiration from nonsaturated land surfaces with conventional meteorological data

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Science China Earth Sciences 2004年第3期47卷 239-246页

作者： QIU Xinfa1, ZENG Yan2. MIAO Qilong1 & YU Qiang2.1. department of Geography, Nanjing Institute of Meteorology, Nanjing 2.0044, China 2. Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, beijing 100101, China Nanjing Inst Meteorol Dept Geog Nanjing 210044 Peoples R China Chinese Acad Sci Inst Geog Sci Beijing 100101 Peoples R China Chinese Acad Sci Nat Resources Res Beijing 100101 Peoples R China

Views diverge greatly on the relationship between actual evapotranspiration (AE) and potential evapotranspiration (PE). Penman showed that AE is determined in intensity by PE and changes proportionally as a function of PE. In contrast, Bouchet indicated that AE deter-mines PE and varies inversely with PE. Based on nearly 30 years data from 432.weather stations and 512.hydrological stations in China, the two different theories, Penman抯 assumption and Bouchet抯 complementary relationship between AE and PE, were tested on nine river basins. With data integration technique, the complementary relationship between AE and PE was dis-played entirely. A general model to estimate the actual evapotranspiration from nonsaturated surfaces by routine meteorological observations has been established on the basis of thorough analysis of the concept of PE. The results show that the calculations are all in error control of <10%, except for a few years over the Yellow River Basin.

关键词： complementary relationship of evapotranspiration, potential evapotranspiration, actual evapotranspiration.

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