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REACTION OF CARBON MONOXIDE AND HYDROGEN ON M-Zr CATALYSTS—VERY HIGH SELECTIVITY TO ETHYLENE

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Journal of Energy Chemistry 1992年第4期 304-314页

作者： ZHANG Wen-Zhong SU Gui-Qin GAO Run-Xiong YIN Yuan-Qi lanzhou Institute of Chemical Physics,Academia Sinica,lanzhou,gansu 730000

Hydrogenation of carbon monoxide over M-Zr catalysts selectivelyproduces ethylene（>90%）in a short time at 360℃,in the stream of 0.8MPa syngas（H/CO=4.5/1）with a space velocity of 345 *** distribution of formed hydrocarbons does not obey the *** of the catalysts makes them be deactivated in 3 *** and Ncan recover CO conversion of catalysts（the former even en-hance it greatly）,but can not recover their selectivity to *** be-haviour of M-Zr catalysts seems to be controlled by their acidity and basici-ty.

关键词： Zr VERY HIGH SELECTIVITY TO ETHYLENE REACTION OF CARBON MONOXIDE AND HYDROGEN ON M-Zr CATALYSTS

OXIDATIVE COUPLING OF METHANE OVER Co2O3-Na2B4O7/SiO2 CATALYST DOPED WITH SODIUM CHLORIDE

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Journal of Energy Chemistry 1994年第3期 306-311页

作者： WU Jin-Gang LI Shu-BenState Key Laboratory of Oxo Synthesis and Selective Oxidation lanzhou Institute of Chemical Physics, Academia Smca lanzhou, gansu 730000

Alkali chloride-doped transition metal（Co） oxide Pnduced ethyleneselectively in oxidative coupling of *** effect of the content of thecomponent,the preparative method and the calcination time on Cyield hasbeen investigated for NaCl-CoO-NaBO/*** ratio of ethyleneto ethane decreases with the prolonged *** deactivation of the cat-alyst has simply been investigated with XRD spectrum.

关键词： SiO Co IT Na OXIDATIVE COUPLING OF METHANE OVER Co2O3-Na2B4O7/SiO2 CATALYST DOPED WITH SODIUM CHLORIDE

Are nuclear loci ideal for barcoding plants? A case study of genetic delimitation of two sister species using multiple loci and multiple intraspecific individuals

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Journal of Systematics and Evolution 2011年第3期49卷 182-188页

作者： 1Qian WANG 1,2Qiu-Shi YU 1Jian-Quan LIU* 1(Molecular Ecology Group,Key Laboratory of Arid and Grassland Ecology,College of Life Sciences,lanzhou University,lanzhou 730000,China) 2(State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating,gansu Desert Control Research Institute,lanzhou 730070,China) (Molecular Ecology Group Key Laboratory of Arid and Grassland Ecology College of Life Sciences Lanzhou University Lanzhou 730000 China) (State Key Laboratory Breeding Base of Desertification and Aeolian Sand Disaster Combating Gansu Desert Control Research Institute Lanzhou 730070 China)

Considerable debate remains as to which DNA region should be used to barcode *** different chloroplast(cp) DNA regions(rbcL,matK,and trnH-psbA) and nuclear ribosomal internal transcribed regions(ITS) have been suggested as suitable barcodes in ***,low-copy nuclear loci were also suggested to be potentially ideal barcode *** aim of the present study was to test the effectiveness of these proposed DNA fragments and five additional low-copy loci(CHS,DET1,COP1,PGIC1,and RPS2;comprising both coding and non-coding regions) in barcoding closely related *** examined the divergences within and between two species of Pugionium(Brassicaceae).We failed to find any interspecific variation from three cpDNA fragments with which to discriminate the two ***,a single base mutation in the internal transcribed spacer(ITS) could discriminate between the two species *** found more variations among all individuals of the two species using each of the other five low-copy nuclear ***,only alleles from one locus(DET1) of the five low-copy loci related to ?owering regulations was able to distinguish the sampled individuals into two *** failed to amplify the corresponding fragments out of Brassicaceae using the designed DET1 *** further discussed the discrimination power of different loci due to incomplete lineage sorting,gene ?ow,and species-specific *** results highlight the possibility of using the nuclear ITS as a core or complementary fragment to barcode recent diverged species.

关键词： chloroplast DNA DNA barcoding internal transcribed spacer(ITS) low-copy nuclear loci Pugionium.

The　Numerical　modelling　of　Two－dimensional　Unsteady　Flow　in　Open　Channel　with　Double－line　Bridge

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Journal of Hydrodynamics 1994年第2期6卷 1-7页

作者： Wang Hua-rong Liu You-lu Chu Yan-dong(Department of Basic Courses, lanzhou Railway Institute, lanzhou,gansu 730070,P.R.China )

In this paper the velocity field and water level height of two- dimensional unsteady flow in open channel with double-line bridge are modelled with finite difference method of alternate *** ADI method is modified according to the rapidly changed speed of the *** empirical formulas are reasonably chosen at the inner-boundary,the calculating steadiness is increased and the calculating results improved. These are closer to real data.

关键词： numerical modeling,boundary conditons velocity field water stage

Microstructures and corrosion properties of casting in situ Al_3Ti-Al composites

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Rare Metals 2010年第1期29卷 78-85页

作者： CHEN Tijun LI Jian HAO Yuan gansu Key Laboratory of Advanced Nonferrous Materials Lanzhou University of Technology Lanzhou 730050 China School of Material Science and Engineering Xi＇an Shiyou University Xi ＇an 710065 China

The effects of Ti content and the alloying elements of Si and Cu on the microstructures of casting in situ Al3Ti-Al composites were investigated. Simultaneously, their corrosion properties were also discussed. The results indicate that the aspect ratios of Al3Ti platelets in different Al based composites are different although all of them are in flaky shape. The morphologies of Al3Ti phase are not only determined by Ti content, but are also related to the alloying elements. The grain refining role of Al3Ti phase in the pure Al and Al-Cu based composites is more effective than that in the Al-Si based composite. The addition of Ti decreases the corrosion resistance of pure Al and Al alloys. The corrosion resistances of the composites are dependent on both the corrosion characteristics of the corresponding matrixes and the distribution of Al3Ti platelets.

关键词： metal matrix composite microstructure corrosion resistance alloying element morphology

THE SYSTEMATIC DYNAMIC EMULATION ON THE AGRICULTURAL DEVELOPMENT ON THE LOESS PLATEAU

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干旱区资源与环境 1993年第Z1期7卷 471-475页

作者： Lin Haiming Huang Gaobao Chen Yuan Yu Shiming gansu Agricultural University, lanzhou, 730070

The Loess Plateau, covered with thick loess, lies in the middle reaches of the YellowRiver to the west of the Taihangshan Mountains, east of the Wuqiao Mountains south ofYinshan Mountains and north of the Qinling Mountains with a total area of 56×10~4km^*** plateau is 1000--2500m above sea level and has loess as thick as 100--200 metres, be-

关键词： The Loess Plateau Semiarid Area Agricultural Region Systematic Dynamics Emulation Study

Synthesis and spectral properties of arylmercury derivatives of α-thiopicolinanilide

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Chinese Journal of Chemistry 1993年第1期11卷 45-52页

作者： SONG,Mao-Ping WU,Yang-Jie Department of Chemistry,Zhengzhou University,Zhengzhou,Henan 450052YANG,Li CHEN,Ji-Hong National Laboratory of Applied Organic Chemistry,lanzhou University,lanzhou,gansu 730000 Department of Chemistry Zhengzhou University Zhengzhou Henan 450052 National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Gansu 730000

A series of thirteen arylmercury derivatives of α-thiopicolinanilide have been synthesized and characterized by elemental analysis,IR,~1H NMR and *** intramolecular coordination and the substituent effects on the MS and ^(199)Hg NMR behaviours have been *** has been shown that a linear correlation exists between the ^(199)Hg chemical shifts and the Hammett-Brown constants σ^+,and the electron-donating groups cause the chemical shift to move upfield.

关键词： Synthesis and spectral properties of arylmercury derivatives of OC thiopicolinanilide Hg

Microstructure and toughness of local brittle zone of HSLA steel multipass weld metals

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China Welding 1992年第2期2卷 122-127页

作者： Yan Cheng Chen Jianhong gansu University of Technology,lanzhou

By using thermo-simulation,Auger analysis and Charpy Ⅴ impact test and with the observation of the microstructures in which cleavage crack was initiated,the morphology and toughness of the local brittle zone of C-Mn and Cr-Ni-Mo multipass weld metals have been *** results indicated that the local brittle zone in C-Mn weld metals with low and high Mn％ and Cr- Ni-Mo weld metals is *** statistical analysis,it has been revealed that the more the local brittle zone and the lower their toughness,the lower the toughness of the entire weld *** alloy elements have a noticeable influ- ence on the toughness of the local brittle zone,thereby changing the toughness of weld metals.

关键词： weld metals local brittle zone microstructure toughness

Qinling-Type Lead-Zinc Deposits

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Acta Geologica Sinica(English Edition) 1993年第1期67卷 79-92页

作者： Li Jianzhong, gansu Institute of Geology for Non-Ferrous Metals, CNNC, lanzhou, gansu He Dianren North west Institute of Geology for Non-Ferrous Metals, CNNC, Xi’an, Shaanxi and Wu Jianmin Research Institute of Geology for Mineral Resources, CNNC, Guilin, Guangxi

Qinling-type Pb-Zn deposits are located in the Qinling fold belt, occurring in the fine-clastic and carbonate rocks of the Devonian marine facies. They are reformed sedimentary deposits originating from hydrothermal waters, and may be subdivided into 2 subtypes: hydrothermal sedimentary deposits (Changba subtype) and reformed hydrothermal sedimentary deposits (Bijiashan-Qiandongshan subtype). In comparison with some of the famous Palaeozoic Pb-Zn deposits in the world, the Qinling-type Pb-Zn deposits constitute an independent type, which possesses some characteristics of both hydrothermal sedimentary deposits (Meggen type) and reformed hydrothermal deposits (Mississippi Valley type).

关键词： Qinling-type lead zinc deposit Changba subtype. Bijiashan-Qiandongshan subtype