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高科技与产业化 2024年第9期30卷 20-23页

作者： Qingdao institute of Bioenergy and Process, chinese academy of sciences 中国科学院青岛生物能源与过程研究所

2023年,中国科学院青岛生物能源与过程研究所驰骋奋发、勇毅前行,紧紧围绕“四个率先”和“两加快一努力”的目标要求,进一步强化国家战略科技力量主力军使命担当,共同绘就了研究所繁荣发展的辉煌历程,各项事业取得可喜进展。

关键词：中国科学院生物能源工作进展使命担当研究所主力军辉煌历程青岛

Characterization and Tribological Behavior of Octadecene,Dodecene and Undecenoic Acid Films on Si Substrate

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Journal of Materials Science & Technology 2005年第5期21卷 671-674页

作者： Jinfang ZHOU+ and Shengrong YANGState Key Laboratory of Solid Lubrication, lanzhou institute of Chemical phys.cs, chinese academy of sciences, lanzhou730000, china State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The films of octadecene, dodecene, and undecenoic acid were prepared on H-terminated Si surface in the presence of ultraviolet irradiation. The resulted films were characterized with water-contact angle measurement and infrared spectroscopy. The friction-reducing behavior of the prepared films was examined on a static-dynamic friction coefficient measurement apparatus and on an atomic force microscope. It was found that all the reacted films on the Si substrate showed good friction-reducing ability; especially, the film of the octadecene exhibited the best friction-reducing ability. This was attributed to the transfer of the reacted films onto the counter face with formation of a transfer film on the counterpart surface, which led to the transformation of the sliding between the reacted films and the hard ceramic to fiat between the reacted films and its transfer film on the counterpart surface. The macroscopic and microscopic friction behaviors of the prepared films were dependent on their molecular chain lengths. Thus the octadecene reacted film with the highest degree of ordering arrangement showed the best friction-reducing and antiwear abilities in sliding against Si3N4.

关键词： Alkese Reaction film Hydrogen-terminated silicon Tribological behavior

Review of several problems on the study of eco-hydrological processes in arid zones

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chinese Science Bulletin 2002年第5期47卷 353-360页

作者： ZHAO Wenzhi & CHENG GuodongCold and Arid Regions Environmental and Engineering Research institute, chinese academy of sciences, lanzhou 730000, china State Key Laboratory of Frozen Soil Engineering, chinese academy of sciences, lanzhou 730000, china Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China State Key Laboratory of Frozen Soil Engineering Chinese Academy of Sciences Lanzhou China

Ecosystem degradation is a common and cardinal environmental problem in arid zones. The change in the eco-hydrological processes is the basic cause responsible for such a problem. The study on the eco-hydrological processes in arid zones has become a forefront and focus of the eco-environmental research. Recent studies on eco-hydrological processes in arid zones show that the primary vegetation pattern and its eco-hydrological effect are of the most stable state of the ecosystem in arid zones. Special water absorption ways of plants in arid zones and the hydraulic lift and reverse hydraulic lift functions of some plants are the key mechanisms to maintain the stability of the ecosystem in arid zones. In the case of water shortage, ensuring ecological water requirement and maintaining proper ecological ground- water table are the prerequisite to keep healthful operation of the ecosystem in arid zones. The paper reviews some advances in the study of eco-hydrological processes in arid zones. It puts

关键词： arid zone vegetation pattern eco-hydrological effect hydraulic lift plant water source ecological water requirement.

Neutron distribution and yield produced by 50 MeV/u^(18)O-ion on thick targets

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Nuclear Science and Techniques 1999年第3期10卷 137-142页

作者： LI Guisheng ZHANG Tianmei LI Zongwei SU Youwu ZHANG Shumin (institute of modern phys.cs, the chinese academy of sciences, lanzhou 730000) institute of modern phys.cs Chinese Academy of sciences Lanzhou 730000 China

Neutron energy, fluence rate, angular distributions and dose equivalent rate distributions around the thick Be, Cu, An targets bombarded by 50 MeV/u 18O-ion were measured using a threshold detector activation method. At the same time,the neutron yields of 18O-ion and the neutron emission rates in the forward direction were obtained approximately.

关键词： 18O离子中子分布剂量等价速率

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3 , LI Yuanshou2 , WU Qingbai2 & WANG Yibo3 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of sciences, lanzhou 730000, china 3. Resource and Environment School, lanzhou University, lanzhou 730000, china 1. institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.

Impact of land-use change on hydrological processes in the Maying River basin, china

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Science china Earth sciences 2006年第10期49卷 1098-1110页

作者： WANG Genxu1,3, ZHANG Yu2, LIU Guimin2 & CHEN Lin3 1. institute of Mountain Hazards and Environment, chinese academy of sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research institute, chinese academy of sciences, lanzhou 730000, china 3. Resource and Environment School, lanzhou University, lanzhou 730000, china 1. institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment School Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China

Since the 1960s, dramatic changes have taken place in land-use patterns characterized by the persistent expansion of cultivated land and a continuous decrease in natural woodland and grassland in the arid inland river basins of china. It is very important to assess the effects of such land-use changes on the hydrological processes so vital for water resource management and sustainable development on the catchment scale. The Maying River catchment, a typical arid inland watershed located in the middle of the Hexi Corridor in northwest china, was the site chosen to investigate the hydrological responses to land-use changes. The annual runoff, base flow, maximum peak flow, and typical seasonal runoff in both spring and autumn flood periods were selected as the variables in the hydrological processes. Statistical-trend analysis and curvilinear regression were utilized to detect the trends in hydrological variables while eliminating the climatic influence. The relationship between cultivated land-use and hydrological variables was analyzed based on four periods of land-use variation data collected since 1965. A runoff model was established composed of two factors, i.e., cultivated land use and precipitation. The impact of land use changes, especially in the large ar- eas of upstream woodland and grassland turned into cultivated lands since 1967, has resulted in a mean annual runoff decrease of 28.12%, a base flow decline of 35.32%, a drop in the maximum peak discharge of 35.77%, and mean discharge decreases in spring and autumn of 36.05% and 24.87% respectively, of which the contribution of cultivated land expansion to the influence of annual runoff amounts to 77%-80%, with the contribution to the influence of spring discharge being 73%-81%, and that to the influence of base flow reaching 62%-65%. Thus, a rational regulation policy of land use patterns is vitally important to the sustainable use of water resources and the proper development of the entire catchment.

关键词： land-use change, arid inland river catchment, hydrological process, impact, Maying River.

Fission Angular Distributions for the Incomplete Fusion Reactions

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chinese journal of nuclear phys.cs 1997年第2期19卷 88-94页

作者： Liu Guoxing Chen Keliang Yu Xian Dai Guangxi institute of modern phys.cs,the chinese academy of sciences,lanzhou 730000 中科院近代物理所甘肃兰州

The fission angular distributions for the 16O+159Tb,16O+197Au and 16O+209Bi reac-tions are measured by the solid state nuclear track *** subtraction of the contribu-tion of intermediate mass fragment（IMF）,the fission angular distributions are fitted by thetransitional state statistical model（TSM）and the single-spin standard theory is used to extractthe spins of the fissioning *** relation between spins and bombarding energy is dis-cussed.

关键词： Incomplete fusion Sequential fission Fission nuclei spin

BRST quantization and canonical Ward identity of the supersymmetric electromagnetic interaction system

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Science china(phys.cs,Mechanics & Astronomy) 2007年第3期50卷 339-347页

作者： HUANG YongChang1,3,4, JIANG YunGuo1 & LI XinGuo2,3 1 institute of Theoretical phys.cs, College of Applied sciences, Beijing University of Technology, Beijing 100022, china 2 institute of modern phys.cs, chinese academy of sciences, lanzhou 730000, china 3 Center of Theoretical Nuclear phys.cs, National Laboratory of Heavy Ion Collisions, chinese academy of sciences, lanzhou 730000, china 4 china Center of Advanced Science and Technology (World Laboratory), Beijing 100080, china 1. institute of Theoretical phys.cs College of Applied Sciences Beijing University of Technology Beijing 100022 China 3. Center of Theoretical Nuclear phys.cs National Laboratory of Heavy Ion Collisions Chinese Academy of Sciences Lanzhou 730000 China 4. china Center of Advanced Science and Technology (World Laboratory) Beijing 100080 China 2. institute of modern phys.cs Chinese Academy of Sciences Lanzhou 730000 China

According to the method of path integral quantization for the canonical constrained system in Becchi-Rouet-Stora-Tyutin scheme, the supersymmetric electromagnetic interaction system was quantized. Both the Hamiltonian of the supersymmetric electromagnetic interaction system in phase space and the quantization procedure were simplified. The BRST generator was constructed, and the BRST transforma- tions of supersymmetric fields were gotten; the effective action was calculated, and the generating functional for the Green function was achieved; also, the gauge generator was constructed, and the gauge transformation of the system was ob- tained. Finally, the Ward-Takahashi identities based on the canonical Noether theorem were calculated, and two relations between proper vertices and propaga- tors were obtained.

关键词： supersymmetric electromagnetic interaction BRST quantization Ward identity

Experimental test of a new neutron threshold detector and its application

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Nuclear Science and Techniques 2002年第3期13卷 149-155页

作者： LI Gui-Sheng, ZHANG Tian-Mei, SU You-Wu, LI Shu-Wei(institute of modern phys.cs, the chinese academy of sciences, lanzhou 730000) institute of modern phys.cs the Chinese Academyo f Sciences Lanzhou 730000 institute of modern phys.cs the Chinese Academyo f Sciences Lznahou 730000

The possibility of using 209Bi as a new threshold detector to measurc high-energy neutrons was investigated for the first time. At the same time the experiment measured successfully the emitted neutron fiuence rate, energy spectrum and dose equivalent rate distributions in the heavy ion target area using a detector complex including 209Bi, 115In, 27A1, 19F and 12C samples.

关键词：阈探测器中子谱实验

Analysis of products of thymine irradiated by ^(18)O^(8+) ion beam in N_2O saturated aqueous solution

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Nuclear Science and Techniques 1999年第3期10卷 180-183页

作者： CAI Xichen WEI Zengquan LI Wenjian LIANG Jianping LI Qiang (institute of modern phys.cs, the chinese academy of sciences, lanzhou 730000) institute of modern phys.cs Chinese Academy of sciences Lanzhou 730000 China

Some methods of capillary gas chromatography, such as GC, GC-MS,GC-FT-IR, are used to analyze the products of thymine irradiated by 18O8+ ion beam in N2O saturated aqueous solution. From the results of GC-MS the molecular weight of products can be determined, and from the results of GC-FT-IR some molecular structure information of products can be obtained. By this way the products,5,6-Dihydrothyndne, 5-Hydroxyl-5-Methylhydantoin, 5-Hydroxyl-6-Hydrothymine, 5-Hydro-6-Hydroxylthymine, 5-Hydroxymethyluracil, Trans-Thymine glycol, Cis-Thymine glycol and dimers are determined without separation of them from samples. Though these products are as same as those products of thymine irradiated by γ rays in N2O saturated aqueous solution, the mechanism of thymine irradiated by heavy ion beam in aqueous solution is different from that by γ rays. The main products of thymine irradiated by 18O8+ ion beam in N2O saturated aqueous solution are hydroxyl adducts at 5-6 band of thymine, while the main products of thymine irradiated by γ ray in N2O saturated aqueous solution are dimers of thymine.

关键词： ^18O^8+离子束辐照胸腺碱 N2O饱和水溶液