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chinese Journal of Chemistry 2004年第7期22卷 714-718,615页

作者：魏琴吴丹杜斌张慧欧庆瑜lanzhou institute of {2. physics chinese academy of Sciences lanzhou Gansu 730000 china School of Chemistry & chemical Engineering Jinan University Jinan Shandong 250022 China Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou Gansu 730000 China School of Chemistry & chemical Engineering Jinan University Jinan Shandong 250022 China

The application of 5'-nitrosalicylfluorone (5'-NSF)-molybdenum(VI) complex as a spectroscopic probe was studied. In the buffer medium of HOAc-NaOAc at 3.45 and in the presence of PVA 12. microemulsion, 5'-NSF-Mo(VI) complex combines protein rapidly to form a stable compound, leading to an absorbance decrease at 52. nm of 5'-NSF-Mo(VI) complex. According to this change, microdetermination of protein has been described. Bovine serum albumin (BSA) could be determined in the linear range of 0—16 g昺L-1 with the detection limit of 11 ngmL-1. Many amino acid and metal ions studied do not interfere with the assay. The method possesses high sensitivity as well as high selectivity. It can be used to determine protein in human urine and milk powder successfully. The relative standard deviations are in all instances less than 4.7%, and the recoveries are between 97.6% and 106.0%. Moreover, the binding number of BSA with the complex, which is determined by using molar ratio, Rosenthanl graphic and slope ratio methods, is in good agreement with each other.

关键词： protein spectrophotometry 5'-NSF-Mo(VI) complex microemulsion

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 {2. physics, 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

Organic geochemical studies of sinking particulate material in china sea area Ⅱ——Geochemical significance of compositional features of ketone, aldehyde and alcohol compounds

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chinese Science Bulletin 1997年第22期42卷 1894-1898页

作者： DUAN Yi,CUl Mingzhong, MA Lanhua, SONG Jinming, ZHOU Shixin and LUO Binjie1. lanzhou institute of Geology, {2. academy of Sciences, lanzhou 730000, china 2. Earthquake Research institute of lanzhou, SSB, lanzhou 730000, china 3. institute of Oceanology, {2. academy of Sciences, Qingdao 2.6071, china lanzhou institute of Geology Chinese Academy of Sciences Lanzhou China Earthquake Research institute of lanzhou SSB Lanzhou China institute of Oceanology Chinese Academy of Sciences Qingdao China

SINKING particulate organic matter of the sea plays an important role in marine environment. Itnot only provides food for marine organisms and takes part in chemical cycling, but also pro-vides sedimentary organic matter for marine sediments. Therefore, researchers always payclose attention to the source and processes of transport and transformation of marine sinkingparticulate organic matter. Its transport process can be understood by measuring the

关键词： marine sinking paniculate material composition of lipid compounds organic matter source and biochemical pro-cesses.

The solid lubricating material experiment device for Shenzhou-7 Spaceship

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Science china(Technological Sciences) 2010年第9期53卷 2521-2527页

作者： WANG Ke1,2.REN WeiJia1,WANG ShiDa1 & WENG LiJun3 1 academy of Opto-Electronics,chinese academy of Sciences,Beijing 100190,china 2.Graduate University of chinese academy of Sciences,Beijing 100049,china 3 lanzhou institute of chemical physics,chinese academy of Sciences,lanzhou 730000,china 1. academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China2. Graduate University of Chinese Academy of Sciences Beijing 100049 China3. Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

A solid lubricating material exposure experiment in space is one of the missions during the seventh manned spaceflight of china,and the key is to develop a device which can be fixed reliably outside of the orbital module and can be fetched conveniently by an astronaut during space *** solid lubricating material experiment device needs to be locked reliably in a vibrating and impacting environment during the launch phase,and should meet the requirement that it can be unlocked and fetched reliably by the astronaut wearing an extravehicular spacesuit via simple operations in orbit in an environment of high and low *** for the device we developed,the environmental characteristic of the mission was analyzed,the mechanical analysis and thermal analysis were carried out,and then a mechanism with functions of mechanical locking,structural self-locking and manual unlocking was *** device was verified by a sequence of experiments and was fetched by the astronaut during the flight of the Shenzhou-7 Spaceship.

关键词： manned spaceflight exposure experiment mechanism unlock

Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural Science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2.and Li Jianping2.1. College of Atmospheric Sciences, lanzhou University, lanzhou 730000, {2. 2. LASG, institute of Atmospheric physics, chinese academy of Sciences, Beijing 10002., {2.) College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2.05. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

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 {2. of Sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research institute, chinese {2. 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 2..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.

CORRELATION　BETWEEN　THE　CATALYTC　PROPERTY　AND　Zr^（3＋）　ION　FOR　ZrO_2.IN　CO　HYDROGENATION

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chinese chemical Letters 1996年第3期7卷 269-270页

作者： Wen LI Liang Bo FENG Yuan Qi YIN (lanzhou institute of {2. physics,chinese academy of Science,lanzhou 730000) lanzhou Inst. of chemical {2. Chinese Academy of Sciences Lanzhou 730000

In this letter the catalytic properties of zirconia in CO hydrogenation are presented. Thecatalylsts were prepared under different conditions. Some of them have good activity andselectivity for olefins, especially for isobutcne. The catalysts were characterized by *** results showed that all good catalysts give an EPR signal at g=1.974 which canbe assigned to Ze(3+) on the surface of ZrO2. The probable active center of ZrO2.catalyst wassuggested.

关键词： HYDROGENATION BETWEEN THE AND PROPERTY ZrO2 CORRELATION

C_(19)-DITERPENOID ALKALOIDS OF DELPHINIUM MOLLIPILUM

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chinese chemical Letters 1995年第2期6卷 101-102页

作者： Suo Ming ZHANG Qing Yu Ou(lanzhou institute of {2. physics, chinese academy of Sciences, lanzhou 730000) chinese Acad Sci Lanzhou Inst Chem Phys Lanzhou 730000 Peoples R China

Five C19-diterpenoid alkaloids were isolated from the aerial parts of Delphinium mollipilum ***. Four proved to be the known talitine B,talitine A, browniine and delcosine, while the fifth was a new C19-diterpenoid al...

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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 {2. of Sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and Engineering Research institute, chinese {2. 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 2..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 2..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.

Friction-reducing and antiwear behavior of metal halide-stabilized linear phosphazene derivatives as lubricants for a steel-on-steel contact

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Science china(Technological Sciences) 2005年第3期48卷 282-291页

作者： ZHU Jiamei 1,2., LIU Weimin 2.& LIANG Yongmin 2.1. School of chemical Engineering and Technology, china University of Mining and Technology, Xuzhou 2.1008, china 2. State Key Laboratory of Solid Lubrication, lanzhou institute of chemical physics, chinese academy of Sciences, lanzhou 730000, china 1. School of chemical Engineering and Technology China University of Mining and Technology 221008 Xuzhou China 2. State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences 730000 Lanzhou China

A series of novel metal halide-stabilized linear phosphazene derivatives were synthesized. The friction-reducing and antiwear abilities of the resulting products as the lubricants for a steel-on-steel contact were comparatively investigated on an Optimol SRV oscillating friction and wear tester. The morphology of the worn steel surface was observed on a scanning electron microscope, while the chemical states of some typical elements on the worn steel surface were examined by means of X-ray photoelectron spectroscopy. It was found that both the side branch structures and central metals influenced the friction-reducing and antiwear behaviors of the synthetic derivatives as the lubricants, which was related to the different adsorption activities of the organic compounds composed of different organic ingredients and metallic ions on a nascent metal surface. All the synthetic lubricants except for the iron (III) derivative showed increased antiwear abilities with increasing metallic ionic radius. A protective layer originated from the tribochemical reaction together with the adsorbed boundary lubricating layer containing organic fluorine compounds, nitrogen oxide, and Fe 3 (PO 4 ) 2.plays an important role in improving the friction and wear behavior of the steel-on-steel system.

关键词： metal halide-stabilized linear phosphazene derivatives,lubricant,steel,tribological properties.