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The Effect of Al^(3+), Na^+, NH_4^+ on Ti Content in the Preparation of Ti-ZSM-5

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chinese Chemical Letters 1999年第8期10卷 713-716页

作者： Cheng Hua XU Shao Jie LU Gui Ying DENG Fa Li QIU (chengdu institute of Organic Chemistry. chinese academy of sciences, chengdu 610041) chinese Acad Sci Chengdu Inst Organ Chem Chengdu 610041 Peoples R China

The effect of Al3+, NH, Na+ on the Ti content in the preparation of Ti-ZSM-5.by the isomorphous substitution of ZSM-5.using gaseous TiCl4 as titanium resource has been investigated. It is surprisingly found that although the direct ratio exists between the Ti content and the content of the skeletal Al: y=0.08x2+0.5.x+1.23(here y represents TiO2% and x represents Al2O3%). but the catalytic activities of Ti-ZSM-5.for the oxidation of styrene sharply rise with the decrease of TiO2%. The skeletal Al hinders the Ti incorporation into the framework of molecular sieves characterized by FT-IR technique. At the same . NH ion has no effect on the Ti incorporation. but Na+ ion does.

关键词： Ti-ZSM-5 Ti content styrene catalytic oxidation

Micromorphological Features of Paleo-Stagnic-Anthrosols at Archaeological Site of Sanxingdui,china

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Journal of Mountain Science 2008年第4期5卷 358-366页

作者： HE Yurong HUANG Chengmin XU Xiangming WANG Yanqiang HE Xiubin institute of Mountain Hazards ＆ Environment Chinese Academy of Sciences Chengdu 610041 China Department of Environmental Science and Engineering Sichuan University Chengdu 610065 China

The archaeological site of the Sanxingdui may date back as far as 5.000 years ago. The typical profiles of Palaeo-Stagnic-Anthrosols near the ancient site were selected, which aimed to identify diagnostic horizons employing methodology of soil taxonomic classification and to reveal the micromorphological properties of the paleosols. Under long-term anthropogenic mellowing, the discernible differentiation between anthrostagnic epipedon and its subhorizons as well as hydragric horizon and its subhorizons occurred in Paleo-Stagnie-Anthrosols at the archaeological site of the Sanxingdui. The mieromorphological properties diversified among each specific diagnostic subhorizon, e.g., the developed microstructure in cultivated subhorizon within anthrostagnic epipedon, closely arranged particles and considerable micropores beneficial to both of water conservation and filtration in plow subhorizon within anthrostagnic epipedon, and automorphic optical-orientation clays and calcareous corrosion in hydragric horizons. The findings above of micromorphological features related with diagnostic horizons are significant for soil taxonomic classification.

关键词： Paleo-Stagnic-Anthrosols diagnostichorizon soil micromorphology soil taxonomic classification archaeological site of Sanxingdui china

Syntheses of (3-Benzyl-4-Aroyl-1,2,4-Triazole-5.yl)[5.(3,4,5.Trimethoxylphenyl)-1,3,4-Oxadizole-2-yl] Sulfides

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chinese Chemical Letters 1997年第3期8卷 195-198页

作者： Xiao Ming FENG Rong CHEN Lian Fu TANG and Yao Zhong JIANG (chengdu institute of Organic Chemistry, chinese academy of sciences, chengdu 610041) (To whom correspondence should be addressed ) chinese ACAD SCI CHENGDU INST ORGAN CHEMCHENGDU 610041PEOPLES R CHINA

Twelve new (3-benzyl-4-aroyl-1,2,4-triazole-5.yl)[5.(3,4,5.trimethoxyphenyl)-1,3,4- oxadiazole-2-yl]sulfides(2) have been synthesized from the nucleophilic displacements of 3-benzyl-4- trimethoxyphenyl)-1,3,4-oxadiazole(1). Compounds(2) were screened for their antibacterial activity against *** at 0.01%. The results show that some compounds(2) have strong inhibiting effects

关键词： Chen Zhang Syntheses of Benzyl-4-Aroyl-1,2,4-Triazole-5.yl Oxadizole-2-yl Sulfides Trimethoxylphenyl

Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science china Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1,2, XU Chenghua1, FENG Liangrong1, SUO Jishuan1 & QIU Fali1 1. chengdu institute of Organic Chemistry, chinese academy of sciences, chengdu 610041, china 2. Graduate School of the chinese academy of sciences, Beijing 100039, china 1. chengdu institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Graduate School of the chinese academy of sciences 100039 Beijing China

The present work synthesizes La-Cu4FeAlCO3 catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3 has a hydrotalcite structure. In the phenol hydroxylation with H2O2 catalyzed by La-Cu4FeAlCO3, the effects of reaction time and phenol/H2O2 molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2O2 and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 5..09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3, under the reaction conditions of the molar ratio of phenol/H2O2 1/2, the amount ratio of phenol/catalyst 20, reaction temperature 343 K, reaction time 120 min, 10 mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3 ][C 6 H 5.OH][H 2 O 2]. and the activation energy of Ea=5..37 kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3/H2O2 system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.

Study on the coating of nano-scale SiO_2 film on the surface of nanocrystalline Mg-Al layered double hydroxides

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Science china Chemistry 2005年第2期48卷 107-114页

作者： ZHANG Zejiang1,2,3, MEI Xiujuan2, XU Chenghua1 & QIU Fali1 1. chengdu institute of Organic Chemistry, chinese academy of sciences, chengdu 610041, china 2. Sichuan Fire Research institute of Public Security Ministry, chengdu 611830, china 3. Graduate School of the chinese academy of sciences, Beijing 100039, china Correspondence should be addressed to Zhang Zejiang (email: zzjzzjzz@***) 1. chengdu institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. Sichuan Fire Research institute of Public Security Ministry 611830 Chengdu China 3. Graduate School of the chinese academy of sciences 100039 Beijing China

The coating process of a nano-scale SiO2 film on the nanocrystalline Mg-Al layered double hydroxides via a sol-gel process was investigated. The uniform and dense SiO2film with a thickness of about 5.nm on the nano-LDHs particles was characterized by the solubility test in the dilute HNO3 or HCl acid, TEM and FT-IR, XRD, TG and DSC. The chemical shifts of binding en- ergies of Al 2p, Mg 2p, Si 2s and O 1s on the coated particles indicate that the coating of the SiO2 nano-film on the surface of the nano-LDHs proceeds through the formation of Mg-O-Si and Al-O-Si bonds. The thermal analysis shows that both the SiO2-coated nano-LDHs and the nano-LDHs have a similar mass loss process, in which there are three obvious stages of mass loss in the temperature range of 40—700℃. Furthermore, the more the coatedamount of SiO2on the surface of the nano-LDHs is, the less the mass loss of the samples is at 700℃.The nano- LDHs have two obvious endothermic peaks at 244.67℃ and 430.13℃, whose corresponding heat absorption capacities are 412.28 J/g and 336.30 J/g, respectively. In contrast, the coated nano-LDHs have only one endothermic peak at 243.60℃ with a heat absorption capacity of 221.25.J/g.

关键词： layered double hydroxides, nanocrystalline, silica, coating.

A New Triterpenoid Saponin from Anemone tomentosa

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chinese Chemical Letters 1999年第12期10卷 0-0页

作者： Xun LIAO Shu Lin PENG Bo Gang LI Yao Zu CHEN Li Sheng DING(1. Department of Chemistry, Zhejiang University, Hangzhou 310027||)(2. chengdu institute of biology, chinese academy of sciences, chengdu 610041) Zhejiang Univ Dept Chem Hangzhou 310027 Peoples R China chinese Acad Sci Chengdu Inst Biol Chengdu 610041 Peoples R China

A new triterpenoid saponin, tomentoside (5., together with prosapogenin CP 4 (1),huzhangoside B (2), C (3) and D (4) was isolated from the ethanolic extract of Anemone *** structure was established by spectroscopic an... 详细信息

关键词： Anemone tomentosa triterpenoid saponin tomentoside.

Preliminary results of the study on wind erosion in the Qinghai-Tibetan Plateau using 137Cs technique

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chinese Science Bulletin 2000年第11期45卷 1019-1025页

作者： YAN Ping, DONG Guangrong, ZHANG Xinbao & ZHANG Yiyun1. Key Laboratory of Environmental Change and Natural Disaster, the Ministry of Education of china, Beijing Normal University, Beijing 100875. china 2. institute of Desert Research, chinese academy of sciences, Lanzhou 730000, china 3. institute of Mountain Hazards and Environment, chinese academy of sciences, chengdu 610041, china 4. Department of Physics, Sichuan Union University, chengdu 610041, china Key Laboratory of Environmental Change and Natural Disaster the Ministry of Education of China Beijing Normal University Beijing China institute of Desert Research Chinese Academy of Sciences Lanzhou China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Department of Physics Sichuan Union University Chengdu China

The worldwide fallout of caesium-137 (137Cs) associated with the nuclear weapon tests during the 195.s and 1960s has provided a valuable man-made tracer for studies of soil erosion and sediment delivery. But relatively few researchers have used it to estimate wind erosion. In this note, the 137Cs technique is introduced into the studies of wind erosion and its modern processes inthe Qinghai-Tibetan Plateau. Two 137Cs reference inventories of 982.11 and 2 376.04 Bq · m-2 wereestablished preminarily, distributed in the south and middle-north parts of the studied arearespectively. By analyzing the patterns of 137Cs depth profiles from sampling sites, the aeolianprocesses of erosion and deposition in nearly 40 years have been revealed, i.e. the shrub coppicedunes (S1) and semi-fixed dunefields (S3) experienced the alternation of erosion and deposition,while the grasslands (S4, S6 and S7) and dry farmlands (S5. suffered erosion only. By using 137Csmodel, the average wind erosion rates for shrub coppice

关键词： 137Cs technique Qinghai-Tibetan Plateau wind erosion.

Calculation of the debris flow concentration based on clay content

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Science china(Technological sciences) 2003年第z1期46卷 163-174页

作者： CHEN Ningsheng, CUI Peng, LIU Zhonggang & WEI Fangqiang institute of Mountain Hazards and Environment, chinese academy of sciences and Ministry of Water Resources, chengdu 610041, china chinese Acad Sci Inst Mt Hazards & Environm Chengdu 610041 Peoples R China Minist Water Resources Chengdu 610041 Peoples R China

The debris flow clay content has very tremendous influence on its concentration (γC). It is reported that the concentration can be calculated by applying the relative polynomial based on the clay content. Here one polynomial model and one logarithm model to calculate the concentration based on the clay content for both the ordinary debris flow and viscous debris flow are obtained. The result derives from the statistics and analysis of the relationship between the debris flow concentrations and clay content in 45.debris flow sites located in the southwest of china. The models can be applied for the concentration calculation to those debris flows that are impossible to observe. The models are available to calculate the debris flow concentration, the principles of which are in the clay content affecting on the debris flow formation, movement and suspending particle diameter. The mechanism of the relationship of the clay content and concentration is clear and reliable. The debris flow is usually of micro-viscous when the clay content is low (5. and 10%. But the value decreases with the increasing of the clay content when the clay content is between 10% and 18%. It is apt to transform the soil into the mudflow, when the clay content exceeds 18%. The concentration of the mudflow usually decreases with the increase of the clay content, and this developing tendency reverses to that of the micro-viscous debris flow. There is m

关键词： clay content, debris flow, concentration.

Susceptibility Assessment of Landslides Caused by the Wenchuan Earthquake Using a Logistic Regression Model

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Journal of Mountain Science 2010年第3期7卷 234-245页

作者： SU Fenghuan Key Laboratory of Mountain Hazards and Land Surface Processes Chinese Academy of Sciences Chengdu China institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu China Graduate University of the chinese academy of sciences Beijing China

The Wenchuan earthquake on May 12,2008 caused numerous collapses,landslides,barrier lakes,and debris *** susceptibility mapping is important for evaluation of environmental capacity and also as a guide for post-earthquake *** this paper,a logistic regression model was developed within the framework of GIS to map landslide *** County,a heavily affected area,was selected for the *** of landslides was prepared by interpretation of multi-temporal and multi-resolution remote sensing images(ADS40 aerial imagery,SPOT5.imagery and TM imagery,etc.) and field *** Certainly Factor method was used to find the influencial factors,indicating that lithologic groups,distance from major faults,slope angle,profile curvature,and altitude are the dominant factors influencing *** weight of each factor was determined using a binomial logistic regression *** susceptibility mapping was based on spatial overlay analysis and divided into five *** faults have the most significant impact,and landslides will occur most likely in areas near the *** of the area has a high or very high susceptibility,located in the northeast,south and southwest,including 65.3% of all landslides coincident with the *** susceptibility map can reveal the likelihood of future failures,and it will be useful for planners during the rebuilding process and for future zoning issues.

关键词： Landslide susceptibility WenchuanEarthquake GIS logistic regression certainty factor