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Research and application of CO_2 refrigeration and heat pump cycle

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Science china(Technological Sciences) 2009年第6期52卷 1563-1575页

作者： TIAN Hua,YANG Zhao,LI MinXia & MA YiTai Thermal Energy Research institute,tianjin University,tianjin 3.0072,{3. Thermal Energy Research institute Tianjin University Tianjin China

The environmental problem caused by refrigerant has become the focus all over the *** the most typical natural refrigerant,CO2,of course,becomes the research *** paper introduces the development and application status of CO2 refrigeration and heat pump *** researches on CO2 refrigeration and heat pump,carried out by Thermal Energy Research institute,tianjin University,also are presented in this paper.

关键词： environmental problem natural refrigerant CO2 refrigeration heat pump

Electroabsorption spectrum of substituted polyphenylacetylenes

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Chinese Science Bulletin 1998年第14期43卷 1215-1219页

作者： CHENG Xiaoman Department of Optoelectronic Information Engineering, tianjin institute of Technology, tianjin 3.0191,{3. Department of Optoelectronic Information Engineering Tianjin Institute of Technology Tianjin China

Electroabsorption (EA) measurements on thin films of poly[ o (trimethylsilyl) phenylacetylene] and poly[ o (trimethylsilylmethyl) phenylacetylene] have been performed. The spectral change induced by an exernal electric field (EA spectra) has been observed, which shows the similar shape of the second derivative of the optical absorption spectra. The change in the absorption Δ α is obtained from the EA spectrum, and Δ n is calculated through Kramers_Krong transformation. The optical properties of substituted polyphenylacetylenes (PPAs) were discussed.

关键词： substituted polyphenylacetylenes electroabsorption spectrum optical nonlinearities

A New Fauna——Qinghezhen Fauna——from the Northern Margin of the North china Platform

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Acta Geologica Sinica(English Edition) 1990年第4期64卷 443-459,468-470页

作者： Liu Xiaoliang Wang Dongfang Shenyang institute of geology and mineral {3., Chinese Academy of Geological Sciences Yue Zhao Shenyang institute of geology and mineral {3. Chinese Academy of Geological Sciences

In the Inner Mongolia axis and Jiaoliao anteclise along the northern margin of the North china *** has been found that the strata formerly considered as Archaean and Proterozoic are in fact an ophiolite suitesimilar to the Early Palaeozoic Ondor Sum Group in the Northern Geosyncline region of china. The stratahave been named in northern Liaoning as the Qinghezhen Group. The emphasis of this paper is on the discus-sion of the simall shelly fossils found in the siliceous rocks in the upper part of the Qinghezhen Group. Thisophiolite suite stretches in an E-W direction for about 1000 km along the northern margin of the North chinaPlatform. in which 15 fossil localities with stable stratigraphic horizons have been discovered. In this paper. 4types. 7 genera (including 5 new ones) and 10 species (including 8 new ones and 1 new subspecies) aredescribed, which are collectively referred to as the Qinghezhen Fauna. The characteristics of these fossils are:shell form simple. the maximum length not exceeding 4 mm. with obvious shell wall and wall ornaments. TheQinghezhen Fauna is comparable in shell structure of some genera and species with the Meishucun Fauna inSouth china, but differs from the latter in having only monotonous fossil groups developed in a distinctly va-ried ecological environment. The two faunas may belong to the same evolutionary stage of the Early Cambrianbut have developed parallelly in different regions. The existence of the Qinghezhen Fauna represents an impor-tant biological event in the Early Cambrian in the Northern Geosyncline region of china. The discovery of theQinghezhen Fauna will bring new knowledge and profound influence to a series of problems on basic geologyand mineral deposit prospecting such as the Cambrian faunas. biogeographical povincialism in china and thegeotectonic features of the northern margin of the North china Platform.

关键词： A New Fauna from the Northern Margin of the North china Platform

Computer Simulation and X-ray Diffraction of Nanocrystals

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Journal of Materials Science & Technology 2001年第3期17卷 333-337页

作者： Ming CHANG, Baohe YANG and Xiaolu XI tianjin institute of Technology, tianjin 3.0191,{3. Hao CHANG Hefei institute of Technology, Hefei 23.009,{3. E-mail: changm@*** tianjin Inst. of Technol. Tianjin 300191 China

X-ray diffraction of structure in nanocrystalline alpha -Fe and Cu was studied by atomistic simulation. Atomic position equilibrium was reached by using molecular dynamics method to simulate nanocrystalline structure with Finnis potentials to model interatomic interactions. It was found that the boundary component exhibits short-range order, and the distortion in crystalline component increases with the decrease of grain size.

关键词： Computer Simulation and X-ray Diffraction of Nanocrystals Simulation

Chronological record of the Early Mesozoic underplating in the northern margin of North china—U-Pb chronometry of zircons in the Late Mesozoic andesite from Western Liaoning

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Progress in Natural Science:Materials International 2007年第8期17卷 943-947页

作者： Shao ji'an~(1,2**) Zhang Hongfu~2 Liu Xiaoming~3.Li Zhitong~4 (1.School of Earth and Space Sciences,Peking University,Beijing 100871,china 2.institute of geology and Geophysics and Key Laboratory of {3. resources,Chinese Academy of Sciences,Beijing 100029,china 3.Key Laboratory of Continental Dynamics,Northwestern University,Xi'an 710069,china 4.institute of geology and {3. resources of Shenyang,Shenyang 11003.,china) School of Earth and Space Sciences Peking University Beijing 100871 China Key Laboratory of mineral resources Institute of Geology and Geophysics Chinese Acad. of Sci. Beijing 100029 China Key Laboratory of Continental Dynamics Northwestern University Xi'an 710069 China institute of geology and mineral {3. of Shenyang Shenyang 110032 China

Cathodoluminescence spectroscopic analysis of zircons in the uppermost sanukites of the early Cretaceous Yixian Forma- tion in Western Liaoning reveals zoning structures of the zircons in the volcanic rocks. LA-ICP-MS chronometry shows that the central part of the zircons is remnant zircon with a U-Pb dating of 254 Ma,which is consistent with the age of the Early Mesozoic underplating granulites,and that the periphery is zircon crystallizing out of the host magma with a U-Pb dating of 116 Ma,which is highly consistent with the Ar-Ar dating of the host volcanic *** of the clinopyroxenes xenocrystals in the sanukites are similar to those of the clinopyroxenes in the underplating granulites,indicating that the granulites accreted to the lower crust in the Early Mesozoic have been reformed and disrupted by the upwelling diapers of the asthenosphere and taken part in formation of the sanukites in the Late Mesozoic.

关键词： northern margin of North china Mesozoic volcanic rock U-Pb chronometry of zircon underplating granulite

Combined adjustment project of national astronomical geodetic networks and 2000' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2, SONG Lijie3. WEI Ziqing1, WANG Zhouping2, OUYANG Guichong2, XU Bilin2, WU Xiaoping3.and WANG Junqin4(1. Xi'an Research institute of Surveying and Mapping, Xi'an 710054, china 2. Xi'an Informational and Technical Center of Surveying and Mapping, Xi'an 710054, china 3. Zhengzhou institute of Surveying and Mapping, Zhengzhou 450052, china 4. The First Surveying Team of tianjin, tianjin 3.0140, china) Xi'an Res. Inst. of Surveying and Mapping Xi'an 710054 China Xi'an Info. and Technical Ctr. of Surveying and Mapping Xi'an 710054 China Zhengzhou Inst. of Surveying and Mapping Zhengzhou 450052 China First Surveying Team of tianjin Tianjin 300140 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2000' national GPS control network involve 48519 terrestrial observational stations and 2666 GPS observational stations. In the terrestrial network, 25107 stations are height fixed and 23.12 stations are in three dimensions. 440793.terrestrial observations and 183.68 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2 m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12 m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3.m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

Simulation study of phase retrieval for hard X-ray in-line phase contrast imaging

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 450-458页

作者： YU Bin1,2, PENG Xiang1,2, TIAN Jindong1, NIU Hanben1, DIAO Luhong3.& LI Hua3.1. Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education, institute of Optoelec- tronics, Shenzhen University, Shenzhen 518060, china 2. State Key Laboratory of Precision Measuring Technology and Instruments, tianjin University, tianjin 3.0072,china 3. Key Laboratory of Intelligent Information Processing, institute of Computing Technology, Chinese Academy of Sciences, Beijing 100080,china Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education Institute of Optoelectronics Shenzhen University Shenzhen China State Key Laboratory of Precision Measuring Technology and Instruments Tianjin University Tianjin China Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing China

Two algorithms for the phase retrieval of hard X-ray in-line phase contrast imaging are presented. One is referred to as Iterative Angular Spectrum Algorithm (IASA) and the other is a hybrid algorithm that combines IASA with TIE (transport of intensity equation). The calculations of the algorithms are based on free space propagation of the angular spectrum. The new approaches are demonstrated with numerical simulations. Comparisons with other phase retrieval algorithms are also performed. It is shown that the phase retrieval method combining the IASA and TIE is a promising technique for the application of hard X-ray phase contrast imaging.

关键词： X-ray optics, phase contrast imaging, phase retrieval, angular spectrum, hard X-ray.

THE DEFLUIDIZATION OF THE ROCKS AND GENESIS OF GOLD DEPOSITS DURING DEFORMATION AND METAMORPHISM: AN EXAMPLE FROM THE JINPING MOUNTAIN

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地学前缘 2000年第S1期7卷 411-412页

作者： Li Sheng(Chengdu institute of geology and mineral {3., Chengdu, 610082,china)

The Jinping mountain region on the western margin of the Kang\|Dian axis is situated in the area bordered by the eastern margin of the Qinghai—Xizang Plateau on the west and the western margin of the Yangtze plate on the east, and consists of three\|layer structures: basement (Kang\|Dian axis), detachment zone (sliding surface of lateral extension and thrusting) and the overburden of the Jinping mountain nappe. The intense intracratonic deformation and metamorphism within the Kang\|Dian axis resulted in the activation, migration and enrichment of mineral elements and finally the formation of ore deposits in the Jinping mountain region. As for the Kang\|Dian axis as the crystalline and folded basement, the lower background values ((0 4～0 8)×10 -9 ) of the element Au don’t represent the initial contents, which have mostly been activated and moved away.. In the Lizhuang\|Lawo\|Bazhe zone as the detachment structural zone, the high er background values ((6～10)×10 -9 ) of the element Au don’t represent the initial contents as well, which have received more gold from the multistage ductile shear zones in the detachment zone. As a result of the lower degrees of deformation and metamorphism within the overburden of the Jinping mountain nappe, the lower temperatures and pressures are insufficient to activate and migrate the element Au; the Au contents available represent the initial Au contents ranging between 1 6 and 2×10 -9 , which are equal to the crustal clarke values from Li Tong and Dai Wentian. The activation and migration of the element Au are believed to be governed by the temperatures and transported media especially variable valent elements and their compounds (principally H 2O, Cl, CO 2 , S and Fe). The associated sediments are also correlated with the transported media especially the valence numbers of the above\|mentioned multivalent elements. The element Au often behaves as a liquid phase element and a multivalence\|phile element in the course of deformation a

关键词： defluidization source bed basement detachment zone of ext ension and thrusting (slide surface) overburden

Metallogenic characteristics of epithermal gold deposits in Tianshan, Xinjiang, china

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Chinese Science Bulletin 1999年第S2期44卷 138-139页

作者： FENG Jianzhong~1, FU Shuixing~2, WU Dewen~3.and YANG Zian~3.1. Department of geology, Peking University, Beijing 100871, china 2. Beijing institute of geology for mineral resources, Beijing 100012, china 3. Center of Remote Sensing for geology, CNNC, Beijing 101601, china Department of geology Peking University Beijing 100871 China Beijing institute of geology for mineral {3. Beijing 100012 China Center of Remote Sensing for geology CNNC Beijing 101601 China

TIANSHAN in southern Xinjiang belongs to the Paleozoic island arc system in which volcanic rocks are extensively distributed. A series of epithermal gold deposits such as the Axi, Xitan, Cuiling andShuangfengshan gold deposits have been discovered. 1 Geological settings of epithermal gold deposits in Tianshan, southern Xinjiang Tianshan in southern Xinjiang belongs to the Paleozoic island arc system. To its north is the Kazakhstan plate, and to its north is the Tarim plate. From west to east, the tectonic units are characterizedby Yili island arc, southern Tianshan arc-basin, Jiaoluotage island arc and Xingxingxia island arc. TheEW-trending Tianshan ore belt is controlled by Kanggurtag geosuture. In its west part, it is controlled byShenglidaban geosuture. The linear structure is NNW-trending; from north to south, the faults

关键词： metallogenic characteristics gold deposits Tianshan Xinjiang.