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Hydrogen metabolic pathways of Rhodospirillum rubrum under artificial illumination

Chinese Science Bulletin 2010年第1期55卷 32-37页

作者： ZHU RuiYan1,2.3 & LI JiLun1 1 college of Biological Sciences, State Key Laboratory for Agrobiotechnology, china {2. University, Beijing 100193, china 2.college of environmental and Chemical engineering, Yanshan University, Qinhuangdao 066004, china 3 engineering Research Center for Bioenergy of Hebei Province, Qinhuangdao 066004, china college of Biological Sciences State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100193 China college of environmental and Chemical {2. Yanshan University Qinhuangdao 066004 China engineering Research Center for Bioenergy of Hebei Province Qinhuangdao 066004 China

Multiple enzymes involved in hydrogen metabolism have been detected in photosynthetic bacterium Rhodospirillum rubrum un-der various growth conditions. To investigate hydrogen metabolic pathways and the contribution of each pathway to hydrogen photoproduction in R. rubrum under the artificial illumination condition, three mutants were constructed, including nifHanfDG double mutant lacking both Fe-nitrogenase and Mo-nitrogenase, anfDG mutant lacking Fe-nitrogenase and nifHhupL double mu-tant (uptake hydrogenase deficient mutant). Comparison of the hydrogen production of these 3 mutants with R. rubrum wild type and the uptake hydrogenase deficient mutant showed that there was a third pathway involved in hydrogen production besides Mo-nitrogenase and Fe-nitrogenase, which mainly contributed to hydrogen evolution. Only a small portion of hydrogen was gen-erated by the third pathway. The hydrogen produced by Mo-nitrogenase, Fe-nitrogenase and the third pathway was about 93.5%, 4.9% and 1.5%, respectively, while the hydrogen consumed by uptake hydrogenase was about 13.3%. The investigation of the formate-linked hydrogenase activity indicated that the third pathway for hydrogen production was not mediated by the for-mate-linked hydrogenase, but probably by some unknown enzyme.

关键词：氢代谢人工照明代谢途径红螺菌固氮酶脱氢酶突变体体吸收

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Ability of Agrogyron elongatum to accumulate the single metal of cadmium, copper, nickel and lead and root exudation of organic acids

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Journal of environmental Sciences 2001年第3期13卷 368-375页

作者： YANG Hong 1, Jongathan W.C.Wong 2. YANG Zhi min\+1, ZHOU Li xiang 1(1. college of Science, Nanjing agricultural University, Nanjing\ 2.0095,{2.. 2. department of Biology, Hong Kong Baptist University,{2.) college of Science Nanjing Agricultural University Nanjing 210095 China.

Agrogyron elongatum were grown in nutrient solution containing moderate to high amounts of separate heavy metal of Cd, Cu, Ni and Ph in a greenhouse for a 9 - day. Cd, Cu, Ni and Ph generally led to decrease in the elongation of roots although the length of seedlings exposed to Cd and Ph at 0.05 and 0.5 mg/L showed to be slightly greater than that of controls. Of the four metals in the experiment, Ph was absorbed and accumulated to the highest level, with the concentrations of 92.54 mg/kg dry weight (DW) in roots and 11683 mg/kg DW in shoots. Cd was moderately accumulated in Agrogyron elongatum, but the maximum bioaccumulation coefficients (BCs) for roots and shoots were observed. The patterns for Cu and Ni uptake and distribution in plants differed from those of Ph and Cd, as it was showed that the shoot accumulation of Cu and Ni was significantly higher than in roots. A. elongation had the highest Ni concentration in shoots (302.1 mg/kg DW) at the external concentration of 2.0 mg/L. Cu ranked second, with a shoot concentration of 12.30 mg/kg DW when 50 mg/L Cu in solution was applied. For the four trace elements tested, the highest concentrations in shoots decreased by the order of Ni > Cu > Ph > Cd (mg/kg DW), and those in roots were Ph > Cd > Ni > Cu (mg/kg DW). Malic, oxalic and citric acids exuded by roots exposed to 1 and 50 mg/L of the metals were detected. Release of organic acids from plants significantly differed among the metal treatments. Cu was most effectively in inducing root exudation of the three types of organic acids. Cd, and Ni were also the inducers of secretion of malic and oxalic acids. With reference of Pb, a small amounts of malic and oxalic acids were detected in the root exudates, but few quantities, of citric acid were. found. However, no correlation between alternations in root exudation of organic acids and metal accumulation could be established.

关键词： heavy metal organic acid Agrogyron elongation hyperaccumulation

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Geodynamic significance of the A-type granites in the Sawuer region in west Junggar, Xinjiang: Rock geochemistry and SHRIMP zircon age evidence

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Science china Earth Sciences 2006年第2期49卷 113-123页

作者： ZHOU Taofa1, YUAN Feng1, TAN Lugui1,2. FAN Yu1 & YUE Shucang1 1. School of Resources and environmental engineering, Hefei University of Technology, Hefei 2.0009,{2. 2. department of Geography and Environment Science, Wanxi college, Liuan 2.7012.{2. 1. School of Resources and environmental engineering Hefei University of Technology Hefei 230009 China 2. department of Geography and Environment Science Wanxi College Liuan 237012 China

Sawuer region is located in west Junggar, Jimunai County of Altay district and Hefeng County of Tacheng district, Xinjiang. The region is along the north margin of Kazakstan-Junggar plate. The intrusions (mainly acid) are widespread. Qiaqihai and Kuoyitasi intrusions are important in the region, with the characteristics of A-type granite. Further investigations indicate that they belong to A2.type granite that formed in extension tectonic setting of post collision. The REE chon-drite-normalized patterns of the intrusions show LREE enrichment and the δ Eu values are lower. The Nd, Sr, Pb isotope compositions of the intrusions indicate a mantle source, while the low δ 18O values resulted from the isotope exchange between intrusion and meteoric water. According to SHRIMP U-Pb age analysis results, the crystallization age of Qiaqihai intrusion is 2.0.7 ± 9.3 Ma (1σ ), and that of Kuoyitasi intrusion is 2.7.9 ± 4.6 Ma (1σ ), corresponding to the beginning of early Permian. The A2.type granites indicate that the region was in the extension period of the post-collisional stage at the beginning of early Permian in the Sawuer region. The A-type granites in the Sawuer region in west Junggar discovered from this work is analogous to the A-type granites found in east Junggar of the Ulungur alkali granites belt. The confirmation of post-collisional A-type granites of early Permian in the Sawuer region provides new evidence for the regional vertical continental crust growth in early Per-mian. The former proposed Ulungur alkali granites belt can extend from east Ulungur through west Ulungur and to Zhaisang in Kazakstan westwards.

关键词： A-type granite, zircon, SHRIMP age, post-collision, Junggar, Xinjiang.

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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. {2. 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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Nonsingularity in second-order cone programming via the smoothing metric projector

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Science china Mathematics 2010年第4期53卷 1025-1038页

作者： WANG Yun 1,& ZHANG LiWei 2.1 college of Information Sciences and engineering,Shandong {2. University,Tai’an 2.1018,china 2.department of Applied Mathematics,Dalian University of Technology,Dalian 11602.,china 1. college of Information Sciences and engineering Shandong Agricultural University Tai’an 271018 China2. Department of Applied Mathematics Dalian University of Technology Dalian 116024 China

Based on the differential properties of the smoothing metric projector onto the second-order cone,we prove that,for a locally optimal solution to a nonlinear second-order cone programming problem,the nonsingularity of the Clarke's generalized Jacobian of the smoothing Karush-Kuhn-Tucker system,constructed by the smoothing metric projector,is equivalent to the strong second-order sufficient condition and constraint nondegeneracy,which is in turn equivalent to the strong regularity of the Karush-Kuhn-Tucker ***,this nonsingularity property guarantees the quadratic convergence of the corresponding smoothing Newton method for solving a Karush-Kuhn-Tucker ***,the analysis does not need the strict complementarity condition.

关键词： second-order cone programming problem smoothing metric projector B-subdifferential Clarke’s generalized Jacobian smoothing Newton method

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Self-centering seismic retrofit scheme for reinforced concrete frame structures:SDOF system study

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Earthquake engineering and engineering Vibration 2010年第2期9卷 271-283页

作者： Yunfeng Zhang and Xiaobin Hu department of Civil and environmental {2.,University of Maryland,college Park,MD 2.742.USA department of Civil and environmental {2. University of Maryland College Park 20742 USA

This paper presents the results of a parametric study of self-centering seismic retrofit schemes for reinforced concrete (RC) frame buildings. The self-centering retrofit system features flag-shaped hysteresis and minimal residual deformation. For comparison purpose,an alternate seismic retrofit scheme that uses a bilinear-hysteresis retrofit system such as buckling-restrained braces (BRB) is also considered in this paper. The parametric study was carried out in a single-degree-of-freedom (SDOF) system framework since a multi-story building structure may be idealized as an equivalent SDOF system and investigation of the performance of this equivalent SDOF system can provide insight into the seismic response of the multi-story building. A peak-oriented hysteresis model which can consider the strength and stiffness degradation is used to describe the hysteretic behavior of RC structures. The parametric study involves two key parameters -the strength ratio and elastic stiffness ratio between the seismic retrofit system and the original RC frame. An ensemble of 172.earthquake ground motion records scaled to the design basis earthquake in California with a probability of exceedance of 10% in 50 years was constructed for the simulation-based parametric study. The effectiveness of the two seismic retrofit schemes considered in this study is evaluated in terms of peak displacement ratio,peak acceleration ratio,energy dissipation demand ratio and residual displacement ratio between the SDOF systems with and without retrofit. It is found from this parametric study that RC structures retrofitted with the self-centering retrofit scheme (SCRS) can achieve a seismic performance level comparable to the bilinear-hysteresis retrofit scheme (BHRS) in terms of peak displacement and energy dissipation demand ratio while having negligible residual displacement after earthquake.

关键词： earthquake reinforced concrete frame structure nonlinear analysis SDOF system seismic retrofit self-centering

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Status of study on biological and toxicological effects of nanoscale materials

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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. {2. of Chemistry and Molecular engineering, Peking University, Beijing 100871, 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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SO_4^(2.)/TiO_2.MoO_3催化剂催化合成缩醛(酮)

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石油化工 2003年第11期32卷 944-948页

作者：杨水金白爱民孙聚堂湖北师范学院化学与环境工程系湖北黄石435002 武汉大学化学与分子科学学院湖北武汉430072

以固体超强酸SO42./TiO2.MoO3为催化剂,对以环己酮、丁酮、正丁醛、异丁醛和乙二醇、丙二醇为原料合成缩醛(酮)的反应条件进行了研究。实验表明,固体超强酸SO42./TiO2.MoO3是合成缩醛(酮)的良好催化剂,较系统地研究了醛(酮)/醇摩尔比、... 详细信息

以固体超强酸SO42./TiO2.MoO3为催化剂,对以环己酮、丁酮、正丁醛、异丁醛和乙二醇、丙二醇为原料合成缩醛(酮)的反应条件进行了研究。实验表明,固体超强酸SO42./TiO2.MoO3是合成缩醛(酮)的良好催化剂,较系统地研究了醛(酮)/醇摩尔比、催化剂用量、反应时间诸因素对产品收率的影响。最佳反应条件为:n(醇)/n(酮或醛)=1.3/1或1.5/1,催化剂用量为反应物料总质量的0.2.％～1.5％,反应时间为1.0 h。在最佳反应条件下,环己酮-乙二醇缩酮的收率为82.7％,环己酮-1,2.丙二醇缩酮的收率为83.4％,丁酮-乙二醇缩酮的收率为74.1％,丁酮-1,2.丙二醇缩酮的收率为94.9％,丁醛-乙二醇缩醛的收率为68.1％,丁醛-1,2.丙二醇缩醛的收率为87.5％,异丁醛-乙二醇缩醛的收率为70.7％,异丁醛-1,2.丙二醇缩醛的收率为82.5％。

关键词：缩醛缩酮 SO4^2./TiO2.MoO3环己酮丁酮正丁醛异丁醛乙二醇催化合成

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Israeli Water Achievements Today and Enlightenment to china

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Chinese Journal of Population,Resources and Environment 2008年第4期6卷 72-77页

作者： Sun Lei1,2. Xu Lanqing3 1. Institute of environmental Science and engineering, Ocean University of{2., Qingdao Shandong 2.6100,{2. 2. department of Soil and Water Sciences, Faculty of agricultural, Food and environmental Quality Sciences, the Hebrew University of Jerusalem, 76100, Israel 3. Logistics Group of Ocean University of{2., Qingdao Shandong 2.6100,{2. Institute of environmental Science and engineering Ocean University of China Qingdao Shandong 266100 China department of Soil and Water Sciences Faculty of Agricultural Food and Environmental Quality Sciences the Hebrew University of Jerusalem 76100 Israel Logistics Group of Ocean University of china Qingdao Shandong 266100 China

Despite the endemic drought, arid climate and associated limited freshwater resources, as well as difficult geopolitical realities, Israel can provide a reliable supply of high quality water to a rapidly growing population. The achievements of water supply in Israel can be summarized as water technologies (like water transportation and purification, desalination, wastewater treatment, effluent reuse, storm water catchment, control systems, rain enhancement and drip irrigation, etc.), water management and legislation as well as water industry. In view of the national concern regarding the quality and quantity of the water, the skills, technologies and know-how that Israel has accumulated in water supply and irrigation can give us enlightenment that is also presented in this paper.

关键词： Israel china water technology water management water industry

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Research on Indicator System of Regional Eco-efficiency:A Case Study of Chengyang District

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Chinese Journal of Population,Resources and Environment 2006年第4期4卷 54-58页

作者： Zhou Zhenfeng1,2.Sun Lei2.Sun Yinglan2.1.college of Resources&Environment,Laiyang agricultural college,Qingdao,Shandong 2.6109,china 2.School of environmental Science and engineering,Ocean University of china,Qingdao,Shandong 2.6003,china college of Resources & Environment Laiyang Agricultural College Qingdao Shandong 266109 China School of environmental Science and engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China School of Environmental Science and Engineering Ocean University of China Qingdao Shandong 266003 China

Eco-efficiency is a valuable tool for managing and solving issues involving resource consumption and pollution emission in current production *** the popularity of the term"eco-efficiency"in business,limited attention has been paid to measuring and reporting regional eco-efficiency for local government policy *** on the concept and method of eco-efficiency,an indicator system of regional eco-efficiency is established in this *** indicator system comprises 2. indicators,which are divided in to three categories including socio-economic development,resources consumption, environmental *** a promising statistical technique, principle component analysis is used to set the weight of indicators which attempts to calculate the eco-efficiency indices of Qingdao's Chengyang *** results show that the eco-efficiency of Chengyang District has clearly improved 35.1% with small fluctuation from 1995 to ***-economic development index and resources consumption index also represent obvious increasing *** correlation coefficient between soci-economic development index and resources consumption index is 0.979,which means the social progress and economic growth of Chengyang District depend on an extravagant consumption of *** environmental pressure index increased slowly before 1997 and declined gradually after 1997,due to more attention being paid to environmental protection by local government in recent *** District still keeps the traditional economic development mode with a high consumption and high production,so the emphases of future development should put on improving the improving the efficient use of natural resources and promoting environmental management *** results show that the indicators system of regional eco-efficiency is a promising method to quantitatively evaluate resources and environmental efficiency and provide an effective decision-making support for local governments.

关键词： regional eco-efficiency indicator system Ecoefficiency Synthetic Index (ESI) Principle Component Analysis (PCA)

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