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Study on Hydrothermal Stability and Catalytic Activity of Al-SBA-15 Mesoporous Materials Prepared by Impregnation Method

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China Petroleum Processing & Petrochemical Technology 2011年第3期13卷 33-40页

作者： Fu Jiquan Li Meng (Center of Chemical Engineering,beijing Key Lab.,beijing institute of Fashion Technology,beijing {4.) Center of Chemical Engineering Beijing Key Lab. Beijing Institute of Fashion Technology Beijing 100029 China

The mesoporous Al-SBA-15 zeolite was obtained via impregnation of pure silica-based SBA-15 zeolite with aluminum *** Al-SBA-15 sample was calcined in air at 800 ℃ for 6 h and hydrothermally treated at near 100 ℃ for 120 h,respectively,and then the thermal and hydrothermal stability of Al-SBA-15 sample was investigated by X-ray diffractometry (XRD),scanning electron microscopy (SEM),transmission electron microscopy (TEM) and nitrogen adsorption and desorption *** Al-SBA-15 sample was also studied by 27 Al nuclear magnetic resonance (27 Al NMR) and ammonia temperature programmed desorption (NH 3.TPD) *** addition,the catalytic activity of Al-SBA-15 zeolite was investigated by the Friedel-Crafts reactions of 2,4.di-tert-butylphenol with cinnamyl *** test results showed that the thermal and hydrothermal stability of Al-SBA-15 zeolite was better than that of SBA-15 *** Al-SBA-15 zeolite sample prepared by impregnation method exhibits more framework aluminum species and Al-O-Si ***,the number of the surface hydroxyl groups was reduced,resulting in the stabilization of framework structure ofAl-SBA-15 *** aluminum species can form weak and medium-strong acid sites with catalytic activity.

关键词： Al-SBA-15 zeolite mesoporous material hydrothermal stability acid site catalytic activity

ELTA-WAVE IN A SIMPLE 1-D 2 x 2 HYPERBOLIC PROBLEM

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Journal of Computational Mathematics 1996年第4期14卷 311-318页

作者： S.L. Yang(institute of applied Mathematics, Chinese Academy of Sciences, beijing, China) institute of applied Mathematics Chinese Academy of Sciences Beijing China

A simple one-dimensional 2 x 2 hyperbolic system is considered in the *** model contains a linear hyperbolic equation, as well as a hyperbolic equation ofwhich the coefficients are about the solution of the linear one. The exact solution ispresented and discussed, then numerical experiments are given by TVD (or MmB)type schemes for Riemann problems. From the results, we know that the solutionsdo have δ-waves for some suitable initial data.

关键词： Zhang Figure DELTA-WAVE IN A SIMPLE 1-D 2 HYPERBOLIC PROBLEM

STUDY ON SEISMOGENIC PROBABILITIES OF POTENTIAL HYPOCENTER REGIONS IN THE CENTRAL QINGHAI-TIBET PLATEAU USING A TECTONOPHYSICAL METHOD

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地震地质 1993年第1期 13-20页

作者： Wang Shengzu(institute of Geology, SSB, beijing 100029)

A deterministic-cum-probabilistic tectonophysical method is used to estimate the hypocentral parameters and seismogenic probabilities of the potential hypocenter regions before and after the Nov. 5. 1988 earthquake (Ms =7) west of Tuotuoheyan in terms of the tectonic feature, stratigraphic structure, geoth-ermal environment, and driving background in the central Qinghai-Tibet plateau. As a result, the earth-quake risk tendency of this area is discussed.

关键词： Qinghai- Tibet plateau. Potential hypocenter region Seismogenic probability. Earthquake risk Tectonophysical method

δ-WAVE FOR 1-D AND 2-D HYPERBOLIC SYSTEMS

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Journal of Computational Mathematics 1996年第3期14卷 256-262页

作者： S.L. Yang(institute of applied Mathematics, Chinese Academy of Sciences, beijing, China) 中科院应用数学所北京

Here a new kind of nonlinear wave, which is called δ-wave, is described by some high resolution difference solutions for Riemann problems of one-dimensional (1-D) and two-dimensional (2-D) nonlinear hyperbolic systems in conservation laws. Some phenomena are numerically shown for the solutions of Riemann problems for 2-D gas dynamics systems

关键词： Zhang WAVE FOR 1-D AND 2-D HYPERBOLIC SYSTEMS

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking

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Science China Earth Sciences 2007年第8期50卷 1266-1272页

作者： YAN BangLiang CMSR, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China CMSR Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.

关键词： Kelvin wave Rossby wave interaction between atmosphere and sea positive feedback

Experimental study of ore gabbro liquid immiscibility

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Science China Earth Sciences 2005年第4期48卷 496-505页

作者： SANG Zunan1,2, XIA Bin1, ZHOU Yongsheng3.& JIN Zhenmin4.1. Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 51064., China 2. Wuhan University, Wuhan 4.0}072, China 3. institute of Geology, China Seismological Bureau, beijing 100029, China 4. Faculty of Earth Sciences, China University of Geosciences, Wuhan 4.0}074. China Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou China Wuhan University Wuhan China institute of Geology China Seismological Bureau Beijing China Faculty of Earth Sciences China University of Geosciences Wuhan China

In this paper, the authors present the results of a preliminary experimental study on partial melting of fine-grained gabbro, Panzhihua, Sichuan Province, China. Experiments were conducted under (confining) pressure ranging from 4.0 to 500 MPa and temperature of 900— 1200℃. The results show that the initial melt is distributed along grain boundaries and triple junctions. Liquid immiscibility phenomena are noted in the melt with two compositional different melt phases, i.e. matrix and sphere phases. The matrix phase is relatively rich in Si, Al and K, and is depleted in Mg, Fe, Ca, Na and Ti, whereas the sphere phase shows opposite trends. The calculation of the melt free energy indicates that the liquid immiscibility is governed by the rule of thermodynamics, as the liquid immiscibility would result in the decrease in free energy of the melt system. The field relationships suggest that the liquid immiscibility may have played an important role in the generation of ore magma of Panzhihua V-Ti magnetite ore deposit. This study thus provides experimental constraints on the mechanism of the formation of V-Ti magnetite deposite.

关键词： partial melting, experimental study, gabbro, liquid immiscibility, ore formation mechanism.

Geophysical survey on the tectonic and sediment distribution of Qinghai Lake basin

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Science China Earth Sciences 2006年第8期49卷 851-861页

作者： AN Zhisheng1, WANG Ping2, SHEN Ji3. ZHANG Yixiang2, ZHANG Peizhen4. WANG Sumin3. LI Xiaoqiang1, SUN Qianli1, SONG Yougui1, AI Li1, ZHANG Yechun2, JIANG Shaoren2, LIU Xingqi3.& WANG Yong3.. {4. of Earth Environment, Chinese Academy of Sciences (CAS), Xi’an 710075, China 2. South China Sea {4. of Oceanology, CAS, Guangzhou 5103.1, China 3. Nanjing {4. of Geography and Limnology, CAS, Nanjing 210008, China 4. {4. of Geology, China Earthquake Administration,{4., China institute of Earth Environment Chinese Academy of Sciences (CAS) Xi’an China South China Sea institute of Oceanology CAS Guangzhou China Nanjing institute of Geography and Limnology CAS Nanjing China institute of Geology China Earthquake Administration Beijing China

The intensive geophysical survey of Qinghai Lake reveals the buried depth of lake sediments and their distribution features. The result indicates that there are three important inter- phases of Qinghai Lake sediments: T1 is the rife interphase of the lake, above which sediments are spread all over the lake basin with roughly the same thickness; T5 is the interphase from which the neotectonic sedimentary cycle begins, and its above sedimentary environment is relatively stable; Tg is the base of the lake basin. Five west-northwest (WNW) fault belts defined the tectonic structure of Qinghai Lake basin: the central hunch around Haixin Shan with two subbasins both in its north and south. The thickness of the lake sediments varies at different places, the thickest sediments are found within the two subbasins. According to the depth that the Sparker System can reach, sediment in the northern subbasin is deeper than 560 m, while sediment in the southern subbasin is deeper than 700 m. The correlation between the seismic sequence stratigraph and the lithology of onshore core shows that Qinghai Lake sediments consist of muddy silt, clay silt, silty clay, gravel silty clay, etc.

关键词： sediment, geophysical survey, Qinghai Lake.

Carbon isotope ratios of C_(4. plants in loess areas of North China

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Science China Earth Sciences 2006年第1期49卷 97-102页

作者： WANG Guoan1,2,3. HAN Jiamao 2, ZHOU Liping3. XIONG Xiaogang4. TAN Ming2, WU Zhenhai5 & PENG Jun6 1. Department of Plant Nutrition, China Agricultural University, beijing 100094. China 2. institute of Geology and Geophysics, Chinese Academy of Sciences,{4., China 3. College of Environmental Sciences, MOE Laboratory for Earth Surface Processes, Peking University, beijing 100871, China 4. institute of Botany, Chinese Academy of Sciences, beijing 100093. China 5. Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, China 6. Network Center, China Agricultural University, beijing 100094. China Department of Plant Nutrition China Agricultural University Beijing China institute of Geology and Geophysics Chinese Academy of Sciences Beijing China College of Environmental Sciences MOE Laboratory for Earth Surface Processes Peking University Beijing China institute of Botany Chinese Academy of Sciences Beijing China Northwest Sci-Tech University of Agriculture and Forestry Yangling China Network Center China Agricultural University Beijing China

Carbon isotope ratios (δ^(13.C) of 89 C_4.plant samples were determined fromthe loess area in North China. δ^(13.C values vary between -10.5per thousand and -14.6per thousandwith a mean of -12.6per thousand. Along a precipitation gradient from the semi-moist area to thesemiarid area, then to the arid area, the δ^(13.C values of C_4.plants show a slight decreasingtrend. The δ^(13.C values of C_4.plants in the dry season are found lower than those in the wetseason. These trends are opposite to those observed for C_3.species.

关键词： C4 plants, carbon isotope ratios, loess area.

Indosinian Foreland Fold-and-Thrust Belt Bordering Yunnan and Guangxi, China

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Acta Geologica Sinica(English Edition) 2001年第4期75卷 391-397页

作者： WU Genyao institute of Geology and Geophysics, Chinese Academy of Sciences, beijing 100029 Chinese Acad Sci Inst Geol & Geophys Beijing 100029 Peoples R China

Recent discoveries of ophiolites indicate that there must be a Palaeotethyan geosuture zone bordering China and Vietnam, which separates the Vietbac block from the South China subcontinent. The Indosinian foreland fold-and-thrust belt bordering Yunnan and Guangxi provided further evidence for the palaeotethysides. The oceanic crust was subducted southwestwards while the magmatic arc migrated northeastwards, and the continent-arc collision occurred in the Late Triassic with the thrusting being extended towards the north or northeast. The features of thrust-nappe structure are discussed, which proved the continental margin of the Palaeotethyan ocean there to be a complicated one. A face-to-face collision occurred first along the NW-striking segment and then along the ENE-striking segment accompanied by transpression or oblique thrusting occurring along the NW-striking one.

关键词： thrust-nappe structure foreland fold-and-thrust belt palaeotethysides border between Yunnan and Guangxi