检索结果-南通市图书馆

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

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

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

Water transfer characteristics during methane hydrate formation and dissociation processes inside saturated sand

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2010年第1期19卷 71-76页

作者： Peng Zhang, Qingbai Wu, Yibin Pu, Guanli Jiang, Jing Zhan, Yingmei Wang State Key Laboratory, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, lanzhou 730000, gansu, China State Key Laboratory Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 Gansu China

Gas hydrates formation and dissociation processes inside porous media are always accompanied by water transfer behavior, which is similar to the water behavior of ice freezing and thawing processes. These processes have been studied by many researchers, but all the studies are so far on the water transfer characteristics outside porous media and the water transfer characteristics inside porous media have been little known. In this study, in order to study the water transfer characteristics inside porous media during methane hydrate formation and dissociation processes, a novel apparatus with three pF-meter sensors which can detect water content changes inside porous media was applied. It was experimentally observed that methane hydrate formation processes were accompanied by water transfer from bottom to top inside porous media, however, the water behavior during hydrate dissociation processes was abnormal, for which more studies are needed to find out the real reason in our future work.

关键词： methane hydrate formation and dissociation processes: water transfer inside porous media saturated

Intensity Distribution of Jingtai Ms 6.2 Earthquake in 1990 and Causative Fault

在线全文

学校读者我要写书评

暂无评论

Earthquake Research in China 1994年第1期8卷 52-62页

作者： Hou Kangming,Zhang Shoujie and Yao TongfuSeismological Institute of lanzhou,SSB,lanzhou 730000,gansu,China

A Ms 6.2 strong earthquake occurred at 16:07 on October 20,1990 in a juncture of the three counties of Jingtai,Tianzhu,Gulang in gansu *** observations indicate that the macroseismic epicenter lies from Xiatang to Daquanwan and that its geographical location is at 37°07’N and 103°37.5’*** epicentral intensity is Ⅷ *** meizoseismal region,covering about 20 km-,is an elliptical area with its long axis orienting *** the circled areas with the earthquake intensity from VI to Ⅷ degree,the formation cause of high intensity(Ⅷ)anomalous area appeared in the Ⅶ area has been discussed in this *** to the data of direct aftershock area,epicentrai intensity area,focal mechanism solution and the direction of the ground motion,etc.,this strong earthquake was caused by latest sinistral lateral movement of Laohushan fault that has been the most active fault since the Holocene.

关键词： epicenter aftershock Holocene houses anomalous elliptical covering geographical disaster strike

Synthesis and spectral properties of arylmercury derivatives of α-thiopicolinanilide

在线全文

学校读者我要写书评

暂无评论

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

Geochemical Characteristics and Origin of Natural Gases in the Qaidam Basin,China

在线全文

学校读者我要写书评

暂无评论

Acta Geologica Sinica(English Edition) 2003年第1期77卷 103-115页

作者： ZHANG Xiaobao, HU Yong, DUAN Yi, MA Liyuan, MENG Zifang, HE Peng,ZHOU Shixin and PENG DehuaState Key Laboratory of Gas Geochemistry, lanzhou Institute of Geology, Chinese Academy ofSciences, lanzhou, gansu 730000 Research Institute of Petroleum Exploration and Development, Qinghai Petroleum Company,CNPC, Dunhuang, gansu 736200 Chinese Acad Sci Lanzhou Inst Geol State Key Lab Gas Geochem Lanzhou 730000 Gansu Peoples R China Qinghai Petr Co Res Inst Petr Explorat & Dev CNPC Dunhuang 736200 Gansu Peoples R China

Sixty-five natural gas samples were collected from 19 oil-gasfields in theQaidam basin, China. The chemical composition and carbon isotope values of the samples weremeasured, and the geochemical characteristics and origin of the natural gases were studied. Thegases can be divided into biogenic gases, sapropelic oil-type gases, mixed type oil-type gases,coal-type gases and mixed gas. The delta^(13)C_1 values of the biogenic gases are very small and theC_2^+ contents of them are very low, ranging from -68.2 per thousand to -61 .8 per thousand and0.06 percent to 0.20 percent respectively. They have heavy delta D and delta^(13)C_(CO_2), showing aCO_2 reduction pathway. They ,are distributed in the East depression region and derived from theQuaternary source rocks. The sapropelic oil-type gases have small delta^(13)C_2 values and highC_2^+ ranging from -36.6 per thousand to -28.6 per thousand and from 33.01 percent to 47.15 percentrespectively. The mixed type oil-type gases have delta^(13)C_2 values and C_2^+ contents varyingfrom -28.6 per thousand to -24.8 per thousand and from 4.81 percent to 26.06 percent *** sapropelic oil-type gases and mixed type oil-type gases are associated with oil-type oils,distributed in the West depression region and derived from the Tertiary saltwater lacustrinesapropelic source rocks and humic source rocks respectively. The delta^(13)C_2 values of thecoal-type gases are extremely high and the C_2^+ contents are very low, changing from -23.3 perthousand to -12.5 per thousand and from 0.06 percent to 18.07 percent respectively. The coal-typegases in the Nanbaxian gasfield and the Lenghu oil-gasfields in the North fault block belt arederived from the Middle Jurassic coal-measures source rocks, whereas those in the West depressionregion are derived from the Tertiary saltwater lacustrine humic source rocks. Compared with someother basins in China, the natural gases there have obviously heavier delta^(13)C due to the heavierdelta^(1

关键词： natural gas geochemical characteristics origin Qaidam basin

PREPARATION AND CHARACTERIZATION OF BIMETALLIC Pd-Fe/Al2O3 CATALYSTS—CHARACTERIZATION BY INFRARED SPECTROSCOPY AND X-RAY DIFFRACTION

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 1994年第1期 1-12页

作者： XIAO Tian-Cun AN Li-Dun TANG Ai-Hua XU Xian-Lunlanzhou histitute of Chemical Physics Academia Sinica lanzhou, gansu 730000

Series of bimetallic catalysts Pd-Fe/AlOwith various palladiumand iron contents were prepared by impregnating metal precursors in *** were employed to characterize the catalysts,XRD forthe existing form of the supported metals,XPS for the surface metal contentsand chemical states,in silu IR with the aid of CO as a probe molecule for theinfluence of iron amount and adding sequence upon the dispersion and the elec-tronic state of *** the catalyst prepared by coimpregnating,the pal-ladium and iron contents are higher than those prepared by impregnating in dif-ferent sequence,but the ratio of Pd/Fe（in atom）is lower than those on thelatter *** iron atoms shield the palladium and enhance the dispersity *** the catalyst prepared by first impregnating with iron and thenwith palladium,the iron has a strong ability to disperse palladium and the dis-persity increases with the iron *** the catalyst prepared by first dopingwith palladium and then iron,the

关键词： Pd CHARACTERIZATION BY INFRARED SPECTROSCOPY AND X-RAY DIFFRACTION PREPARATION AND CHARACTERIZATION OF BIMETALLIC Pd-Fe/Al2O3 CATALYSTS Fe Al

Millennial-scale monsoonal climatic change from paleosol sequences on the Chinese western Loess Plateau and Tibetan Plateau: a brief summary and review

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1999年第S1期44卷 38-52页

作者： FANG Xiao-Min LI Ji-Jun Department of Geography, lanzhou University, lanzhou, gansu 730000, PR China

This paper summarizes the work from the INQUA 1997 Project "Response of soilformation to short-warm-episodes of Asian summer monsoon" and its seeded related internationaland domestic grants. It reviews the effects of the millennial monsoonal changes on the loess-paleosols of the Chinese Loess and Tibetan Plateaus. High-resolution proxy records ofpedogenesis and monsoons demonstrate that both Asian winter and summer monsoons wereunstable and synchronously and inversely coupled during the last glaciation. During that timerapid episodic cycles of cold surges and warm enhancements spanned only ca. 1-2 ka in high-frequency domain. Sub-Milankovitch cycles (6-8 ka) of progressive cooling or weakening in low-frequency domain generally resembled the pattern of the North Atlantic climatic change. However,during the last interglacial, Asian winter and summer monsoons seemed to vary independently, theformer being stable and the later unstable. Soil formation seems to occur in surprisingly fastresponse to the summer monsoon warm enhancements, resulting in weakly or moderatelydeveloped paleosol sequences. North Atlantic and polar cold air surges though the westerlies andother paths, and the north-south swing of the westerlies beside the Tibetan Plateau, may be thealternative mechanisms for the rapid monsoonal changes during the last glacial. But in the lastinterglacial, the summer monsoons worked largely independently.

关键词： Monsoon instability loess-paleosol sequence pedogenesis Tibetan Plateau

THE PERFORMANCE OF MgO/BaCO3 CATALYST FOR METHANE OXIDATIVE COUPLING

在线全文

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 1993年第2期 81-91页

作者： DA Jian-Wen DING Xue-Jia SHEN Shi-Kong State Key Laboratory of Oxo.Synthesis and Selective Oxidation lanzhou Institute of Chemical Physics,Academia Sinica lanzhou,gansu 730000

A new catalyst system composed of mainly alkaline earth metalcompounds has been reported in the *** catalyst,MgO/BaCO3,has ahigh activity and a high C2selectivity for the title *** resultsindicate that high PcH4benefits C2selectivity and high Po2benefits *** optimizing C2yield can be obtained under properly selected reactionconditions.530h stability test shows that the catalyst is very stable during *** carbonation of the catalyst does not affect its activity.

关键词： MgO THE PERFORMANCE OF MgO/BaCO3 CATALYST FOR METHANE OXIDATIVE COUPLING

PREPARATION AND CHARACTERIZATION OF BIMETALLIC Pd-Fe/Al2O3 CATALYSTS—CHARACTERIZATION BY TEM,EDX,XPS and ESR

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chemistry 1994年第1期 13-23页

作者： XIAO Tian-Cun AN Li-Dun TANG Ai-HuaLI Shehg-Li XU Xian-Lunlanzhou Institute of Chemical Physics, Academia Sinica lanzhou, gansu 730000

Suppurted bimetallic catalysts Pd-Fe/AlOwere prepared by im-pregnating method in different dipping *** electron mi-croscopy（TEM-EDX）,X-ray diffraction（XRD）,X-ray photoelectron spec-troscopy（XPS）and electron spin resonance（ESR）were employed to charac-terize the *** is shown that the impregnating sequence has influence onthe diffusiun and distribution of the metals in the pores of *** group diffusion is controlled by its *** the surface of the cata-lysts,the iron is in oxidative state while the palladium is zerovalent whenFeClis first ***,on the surface of the other two,the palladiumis in both oxidated and metallic *** amount of Fein the catalyst dif-fers with the dipping *** results shows that in different catalystsprepared in various sequences Feexists in different environments.

关键词： Pd PREPARATION AND CHARACTERIZATION OF BIMETALLIC Pd-Fe/Al2O3 CATALYSTS CHARACTERIZATION BY TEM,EDX,XPS and ESR Fe TEM EDX XPS Al