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Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs technique

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Chinese Science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. key laboratory of environmental Change and Natural Disaster, the ministry of education of china, Beijing Normal University, Beijing 100875, china 2. Institute of Desert Research, Chinese Academy of Sciences, Lanzhou 730000, china 3. Institute of Mountain Hazards and environment, Chinese Academy of Sciences, Chengdu 610041, china 4. Department of Physics, Sichuan Union University, Chengdu 610041, china key laboratory of environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China Institute of Desert Research Chinese Academy of Sciences Lanzhou China Institute of Mountain Hazards and environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 1950s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2 376.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5) suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

Inter-phase selective corrosion of γ-TiAl alloy in molten salt environment at high temperature

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Progress in Natural Science:Materials International 2011年第4期21卷 322-329页

作者： Wen-yue ZHAO,Bo-wen XU,Yue MA,Sheng-kai GONG key laboratory of Aerospace Materials and Performance(ministry of education), School of Materials Science and Engineering,Beihang University,Beijing 100191,china key laboratory of Aerospace Materials and Performance (ministry of education) School of Materials Science and Engineering Beihang University Beijing 100191 China

Hot corrosion behavior of Ti-48Al-2Cr-2Nb alloy in molten salt environment of 75%Na2SO4and 25%NaCl(mass fraction) at 800℃was studied using oxidation kinetics analysis,scanning electron microscopy,X-ray energy dispersive and X-ray diffraction *** inter-phase selective corrosion,which caused the corrosion pits initiated from lamellar interfaces and the preferential corrosion ofα2phases,was observed during the hot corrosion of the *** common controls of thermodynamic and kinetics in corrosion reactions with fluxing and active oxidation process were considered the essential hot corrosion mechanisms of the ***,lamellar refinement was proved to be an effective way to mitigate the inter-phase selective corrosion of the alloy in molten salts.

关键词： hot corrosion TiAl-based alloy inter-phase selective corrosion molten salts

High-resolution climate change in mid-late Holocene on Tianchi Lake,Liupan Mountain in the Loess Plateau in central china and its significance

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Science Bulletin 2010年第20期55卷 2118-2121页

作者： ZHOU AiFeng,SUN HuiLing,CHEN FaHu ,ZHAO Yan,AN ChengBang,DONG GuangHui,WANG ZongLi & CHEN JianHui Center for Arid environment and Paleoclimate Research,key laboratory of Western china’s environmental System(ministry of education),Lanzhou 730000,china Center for Arid environment and Paleoclimate Research Key Laboratory of Western China’s Environmental System (Ministry of Education) Lanzhou China

According to a core from Tianchi Lake,Liupan Mountain in Loess Plateau sediment,fossil pollen assemblages,magnetic susceptibility(MS)and color scale were measured based on reliable Abies leaf macrofossils radiocarbon *** recovered a very good high-resolution mid-late Holocene climate change achieve for the transition area of the East Asia monsoon region and northwest arid *** results show that the basic climate background was in agreement with the records from cave records in monsoon regions in eastern ***,it shows more detailed records in abrupt climate change.

关键词： high resolution mid-late Holocene Tianchi Lake

Palaeogene fossil Populus leaves from Lanzhou Basin and their palaeoclimatic significance

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Chinese Science Bulletin 2004年第14期49卷 1494-1501页

作者： SUN Bainian1,2, YAN Defei1, XIE Sanping1, CONG Peiyun1, XIN Cunlin1 & YUN Fei1 1. key laboratory of Western china抯 environmental Systems of the ministry of education, Lanzhou University, Lanzhou 730000, china 2. State key laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sci-ences, Nanjing 210008, china key laboratory of Western china''s environmental Systems of the ministry of education Lanzhou University Lanzhou 730000 China State key laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontolog Chinese Academy of Sci- ences Nanjing 210008 China

An angiosperm compression flora is found in Palaeogene from Lanzhou Basin and the cuticular analysis of Populus davidiana Dode in the flora is carefully made. Fur-thermore, the fossil cuticles are compared with the epidermal structures of extant Populus leaves growing in different en-vironments, i.e. moist, semimoist, and semiarid to arid cli-matic regions. The present experiments indicate that mature leaves of P. davidiana show leaf size from big to small, leaf cuticles from thick to thin and anticlinal walls of epidermal cells from faintness to clarity along with the increase of lati-tudes of the plant distributions, the climatic variation from moist to arid, the annual precipitation from more to less and the annual mean temperature from high to low. The fossil P. davidiana differs from the specimens collected from Shandan in semiarid to arid climatic regions but closely resembles the Wushan leaves in a semi-moist climatic area in a lot of fea-tures. In a word, the new research may reflect that the flora lives in a semi-moist climatic environment. The present dis-covery of compression of Paleogene Populus davidiana is of great significance to studying vegetation types, climatic and environmental changes during the primal uplifting of the Qinghai-Tibet Plateau.

关键词：古气候兰州盆地山杨化石角质层早第三纪被子植物

Transfection of promyelocytic leukemia in retrovirus vector inhibits growth of human bladder cancer cells

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Acta Pharmacologica Sinica 2005年第5期26卷 610-615页

作者： Lei LI,Da-lin HE~2 Institute of Urology,First Hospital of Xi'an Jiaotong University,Xi'an 710061,china key laboratory of environment and Genes Related to Diseases of ministry of education,Xi'an Jiaotong University,Xi'an 710061,china InstituteofUrology FirstHospitalofXi'anJiaotongUniversityXi'an710061China

Aim:To construct a recombinant retrovirus vector carrying human promyelocyticleukemia(PML)cDNA and identify its expression and biology role in bladdercancer UM-UC-2 cells for future gene ***:PML full-length cDNAwas inserted into the EcoR I and BamH I site of pLXSN vector containing the longterminal repeat(LTR)*** vector was identified by restriction enzymedigestion and then transfected into PA317 packaging cell line by calcium phos-phate *** cDNA was detected by polymerase chain reaction(PCR)and the protein was identified by laser confocal microscopy and Westernblot in bladder cancer cells,*** morphology was observed byinverted phase contrast microscope,and MTT assay determined growth curve ofthe bladder cancer ***:Restriction enzyme digestion proved that a 2.1kb PML cDNA was inserted into the pLXSN *** assay demonstrated that304 bp fragments were found in UM-UC-2/pLPMLSN *** confocalmicroscopy showed speck dots fluorescence in the UM-UC2/pLPMLSN nucleus.A 90 kD specific brand was found by Western *** assay demonstrated theUM-UC-2/pLPMLSN bladder cancer growth ***:The retroviruspLPMLSN vector was successfully constructed and could generate high effec-tive expression of human PML in bladder cancer cell UM-UC-2,suggesting thatPML recombinant retrovirus have potential utility in the gene therapy for bladdercancer.

关键词： promyelocytic leukemia protein retrovirus gene therapy

EXPERIMENT OF IMPACT OF RIVER HYDRAULIC CHARACTERISTICS ON NUTRIENTS PURIFICATION COEFFICIENT

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Journal of Hydrodynamics 2007年第3期19卷 387-393页

作者： WANG Pei-fang WANG Xiao-rong WANG Chao State key laboratory of Pollution Control and Resource Reuse School of Environment Nanjing University Nanjing 210093 China State key laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai University Nanjing 210098 China key laboratory of Intergrated Regulation and Resource Development on Shallow Lakes College of Environmental Science and Engineering Hohai University Nanjing 210098 China

Hydraulic characteristics of a river are the key factors for river water quality improvement and river restoration. A simulated river was exploited to study the interactions between water contaminant purification coefficients and the characteristics of the river, such as the cross-section velocity, water depth, Reynolds number, and Froude number. To enhance the purification capacity of the river, detritus with 5 mm to 10 mm in diameter and contact surface area per volume of 87.6 m^2/m^3 were constructed naturally at the bed and along one side of the bank to form half shape of the river cross-section. During the one-month experiment （including 3 periods） from the third of November to the fourth of December, 2005, three categories of hydraulic conditions were investigated. Results show that the purification coefficient （K） of Total Nitrogen （TN） is closely coherent with the hydraulic retention time （T）, river length （L）, Reynolds number （Re） and Froude number （Fr）. The relationship of K and T generally agrees with the power law under the three experimental water hydraulic conditions. Based on these results, the optimal Re and Fr ranges can be obtain to serve as a guideline for ecological re-engineering design to improve river water quality and restore river ecosystem.

关键词： Hydraulic characteristics total nitrogen,purification coefficient interaction simulated river

Biological couplings: Function, characteristics and implementation mode

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Science china(Technological Sciences) 2010年第3期53卷 379-387页

作者： REN LuQuan & LIANG YunHong key laboratory of Bionic Engineering of ministry of education, School of Biological and Agricultural Engineering, Jilin University, Changchun 130025, china 1. key laboratory of Bionic Engineering of ministry of education School of Biological and Agricultural Engineering Jilin University Changchun 130025 China

Through rigorous natural selection, biological organisms have evolved exceptional functions highly adaptable to their living environments. Biological organisms can achieve a variety of biological functions efficiently by using the synergic actions of two or more different parts of the body, or the coupling effects of multiple factors, and demonstrate optimal adaptations to the living environment. In this paper, the function, characteristics and types of biological couplings are analyzed, the implementation mechanism and mode of biological coupling functions are revealed from the bionic viewpoint. Finally, the technological prospects of the bionic implementation of biological coupling function are predicted.

关键词： biological coupling biological function biological characteristics implementation mode of biological function coupling bionics

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Storage,Patterns and Controls of Soil Nitrogen in china

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Pedosphere 2007年第6期17卷 776-785页

作者： YANG Yuan-He MA Wen-Hong A. MOHAMMAT FANG Jing-Yun Department of Ecology and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Beijing 100871 （China） School of environment and Urban Study Peking University Shenzhen Graduate School Shenzhen 518055 （China）

Soil holds the largest nitrogen(N)pool in terrestrial ecosystems,but estimates of soil N stock remain controversial. Storage and spatial distribution of soil N in china were estimated and the relationships between soil N density and environmental factors were explored using data from china's Second National Soil Survey and field investigation in northwest china and the Tibetan ***'s soil N storage at a depth of one meter was estimated at 7.4 Pg,with an average density of 0.84 kg m^(-2).Soil N density appeared to be high in southwest and northeast china and low in the middle areas of the *** N density increased from the arid to semi-arid zone in northern china,and decreased from cold-temperate to tropical zone in the eastern part of the *** analysis of general linear model suggested that climate and vegetation determined the spatial pattern of soil N density for natural vegetation,which explained 75.4% of the total variance.

关键词： Climate soil nitrogen soil texture spatial distribution vegetation

Optimization of Agrobacterium tumefaciens-Mediated Immature Embryo Transformation System and Transformation of Glyphosate-Resistant Gene 2mG2-EPSPS in Maize(Zea mays L.)

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Journal of Integrative Agriculture 2013年第12期12卷 2134-2142页

作者： YU Gui-rong LIU Yan DU Wen-ping SONG Jun LIN Min XU Li-yuan XIAO Fang-ming LIU Yong-shengkey laboratory for Bio-Resource and Eco-environment ministry of education/State key laboratory of Hydraulics and Mountain River Engineering College of Life Science Sichuan University key laboratory for Bio-Resource and Eco-environment Ministry of Education/State Key Laboratory of Hydraulics and Mountain River EngineeringCollege of Life ScienceSichuan University Institute of Biotechnology & Nuclear Techniques Sichuan Academy of Agricultural Sciences Crop Sciences Research Institute China Academy of Agricultural Sciences Biotechnology Research Institute China Academy of Agricultural Sciences Department of Plant Soil and Entomological SciencesUniversity of Idaho Moscow

Since maize is one of the most important cereal crops in the world,establishment of an efficient genetic transformation system is critical for its *** the current study,several elite corn lines were tested for suitability of Agrobacterium tumefaciens-mediated transformation by using immature embryos as *** ability and efficiency of transformation of *** *** EHA105 and LBA4404,different heat treatment times of immature embryos before infection,influence of L-cysteine addition in co-cultivation medium after transformation,and how different ways of selection and cultivation influence the efficiency of transformation were ***-resistant gene 2mG2-EPSPS was transformed into several typical maize genotypes including 78599,Zong 31 and BA,under the optimum *** showed that the hypervirulent Agrobacterium tumefaciens *** EHA105 was more infectious than *** of L-cysteine（100 mg L-1） in co-cultivation medium,and heating of the immature embryos for 3 min prior to infection led to a significant increase in the transformation *** in resting medium for 4-10 d and delaying selection was beneficial to the survival of resistant *** induction of germination,adding a high concentration of 6-BA（5 mg L-1） and a low concentration of 2,4-D（0.2 mg L-1） to regeneration medium significantly enhanced germination *** the optimized transformation procedure,more than 800 transgenic plants were obtained from 78599,Zong 31 and *** spraying herbicide glyphosate on leaves of transgenic lines,we identified 66 primary glyphosate-resistant *** transformation efficiency was 8.2%.PCR and Southern-blot analyses confirmed the integration of the transgenes in the maize genome.

关键词： maize immature embryo Agrobacterium tumefaciens-mediated transformation transgenic approach glyphosate resistance