检索结果-南通市图书馆

Chinese Science Bulletin 1998年第10期43卷 837-840页

作者： XU Yigang guangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640, China guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Spinel peridotite xenoliths from Wangqing, NE China exhibit correlative variations in texture, temperature, geochemistry and radiogenic isotopes. This suggests that the Wangqing xenoliths may come from a mantle diapir. It is possible that the fertile and undeformed lherzolites were situated in the interior of the diapir, whereas the refractory and deformed harzburgites and clinopyroxene_poor lherzolites were within the diapiric flanks.

关键词： peridotite xenoliths texture geochemistry Wangqing.

Trace element characteristics and origin of intergranular components in mantle peridotites

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第7期45卷 643-649页

作者： XU Yigangguangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640, China guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

Leaching experiment has been carried out on mantle xenoliths with different petrographic features in order to directly characterize the nature of intergranular components. ICP-MS analyses of leachates show that they are characterized by high LREE concentrations with strong depletion of Ta. The total REE contents and whether the negative Rb, Ba and Nb anomalies are present or not in intergranular components are largely dependent upon the nature of mantle metasomatism experienced by its host rock. It is proposed that intergranular components may represent residues of small volume metasomatic melts.

关键词： peridotite xenoliths intergranular components trace elements upper mantle.

Trace element geochemical characteristics of plants and their influence on the remote-sensing spectral properties in the North Jiangsu oil field

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 2000年第S1期45卷 26-34页

作者： WANG Yunpengguangzhou Institute of Geochemistry, Chinese Academy of Sciences, guangzhou 510640, China Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China

This paper presents the contents of 17 kinds of trace elements in plant leaf samples collected from 4 sections in the North Jiangsu oil field, and the dada on their visible-near infrared spectra. By comparing the results of the inner and outer oil-gas remote-sensing anomaly areas, the plant trace element composition, and the enrichment characteristics and their influence on the plant spectral properties are described. The results indicated that the plant leaves had very strong enrichment ability toward some elements such as Mg, Ca, K, Na, Fe, Al, Mn, V, Zn and Cr. The plant leaves from the oil-gas abnormal areas were enriched in trace elements of the Fe-series, but depleted in alkali and alkali-earth metal elements. The plant trace elements had a strong influence on the 'blue-shift' strength and the reflectance of visible bands. And the ratios between Fe, Co and K, Na, Cd, Cu, Ba are the effective remote-sensing oil-indicating factors of plant trace elements. plant trace element, geochemistry, remote

关键词： plant trace element geochemistry remote sensing spectra North Jiangsu oil fleld.

Superlarge ore deposits and development of China's mineral resources

在线全文

学校读者我要写书评

暂无评论

Chinese Science Bulletin 1999年第15期44卷 1436-1440页

作者： ZHAO Zhenhuaguangzhou Institute of Geochemistry , Chinese Academy of Sciences , guangzhou 510640, China Guangzhau Institute of Geochemistry Chinese Academy of Sciences Guangzhou China

The ever increasing demand of mineral resources in China was assessed and it is suggested that the development of superlarge ore deposits was the best way to meet such demand. Research and exploitation of superlarge ore deposits can bring great economic and social benefits to the society. It is also the best way to a better integration of resource industry development and environmental protection and therefore provides a basis of sustainable development of China. China has made important advancements in the research of superlarge ore deposits and especially in classification, selectivity and confinement of deposit types and temporal and spatial distributions. It is suggested that the metallodynamics and the interaction between the crust and the mantle and the core should be studied. At the same time, a new concept of resources should be established in order to build a new integrated system for research, and resource development and environmental proiection.

关键词： superlarge ore deposit metallodynamics resource-environmental integration.

Free orthodox semigroups and free bands with inverse transversals

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2010年第11期53卷 3015-3026页

作者： TANG XiLin Department of Mathematics, South China University of Technology, guangzhou 510640, China 1. Department of Mathematics South China University of Technology Guangzhou 510640 China

It is well known that the subclass of inverse semigroups and the subclass of completely regular semigroups of the class of regular semigroups form the so called e-varieties of semigroups. However, the class of regular semigroups with inverse transversals does not belong to this variety. We now call this class of semigroups the ist-variety of semigroups, and denote it by IST . In this paper, we consider the class of orthodox semigroups with inverse transversals, which is a special ist-variety and is denoted by OIST . Some previous results given by Tang and Wang on this topic are extended. In particular, the structure of free bands with inverse transversals is investigated. Results of McAlister, McFadden, Blyth and Saito on semigroups with inverse transversals are hence generalized and enriched.

关键词： inverse transversal ist-variety free orthodox semigroup free band

PdCl_2-catalyzed heterocyclotrimerization in MeOH/scCO_2:A versatile approach to dimethyl pyridine-3,5-dicarboxylate from methyl acrylate and urea

在线全文

学校读者我要写书评

暂无评论

Science China Chemistry 2008年第5期51卷 447-451页

作者： ZOU Bo,JIANG HuanFeng College of Chemistry,South China University of Technology,guangzhou 510640,China 1. College of Chemistry South China University of Technology Guangzhou 510640 China

A novel and green method for the synthesis of dimethyl pyridine-3,5-dicarboxylate has been developed. It is PdCl2-catalyzed heterocyclotrimerization of methyl acrylate with urea in methanol/supercritical carbon dioxid... 详细信息

关键词： PdCl2 heterocyclotrimerization dimethyl pyridine-3 5-dicarboxylate scCO2

Efficient transformation and expression of gfp gene in the edible mushroom Pleurotus nebrodensis

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2008年第7期18卷 819-824页

作者： Junfang Lin a,b, Mingyao Zheng a, Jie Wang a,b, Wei Shu c, Liqiong Guo a,b,* a Department of Biotechnology, College of Food Sciences, South China Agricultural University, guangzhou 510640, China b Institute of Biomass Research, South China Agricultural University, guangzhou 510640, China c Test and Experimental Center, South China Agricultural University, guangzhou 510640, China Department of Biotechnology College of Food Sciences South China Agricultural University Guangzhou 510640 China Institute of Biomass Research South China Agricultural University Guangzhou 510640 China Test and Experimental Center South China Agricultural University Guangzhou 510640 China

An efficient transformation method mediated by PEG-protoplasts was developed for the newly commercial edible mushroom Pleu- rotus nebrodensis. Two plasmids were used to co-transform protoplasts of P. nebrodensis. One plasmid is pAN7-1 containing a positive selectable marker gene hph conferring hygromycin B resistance. Another plasmid is pBlue-GFP containing a reporter gene gfp conferring green fluorescent protein. PCR and Southern blot analysis showed that hph gene or/and gfp gene were integrated into the genome of P. nebrodensis transformants. The transformation efficiency of the positive selectable marker gene hph was 3 transformants per microgram of plasmid pAN7-1 DNA, which was about 30 times higher than that previously reported in thoroughly studied Pleurotus species such as Pleurotus ostreatus. The transformation efficiency of the reporter gene gfp was 9 transformants per microgram of plasmid pBlu-GFP DNA. The co-transformation efficiency was 23.68%. This is the first report that a "reporter" gene, green fluorescent protein gene can be successfully stably expressed in this Pleurotus species.

关键词： Pleurotus nebrodensis Protoplast-mediated transformation Green fluorescent protein GFP expression

INTELLIGENT CAR STYLING TECHNIQUE AND SYSTEM BASED ON A NEW AERODYNAMIC-THEORETICAL MODEL

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 Journal of Mechanical Engineering 2002年第2期15卷 110-115页

作者： Huang Xiangdong Xie Chaolin Xie YuecongCollege of Traffic and Communications, South China University of Technology,guangzhou 510640, China College of Traffic and Communications South China University of Technology Guangzhou 510640 China ***

Car styling technique based on a new theoretical model of automotiveaerodynamics is introduced, which is proved to be feasible and effective by wind tunnel *** of a multi-module software system from this technique, including modules of knowledgeprocessing, referential styling and ANN aesthetic evaluation etc, capable of assisting car stylingworks in an intelligent way, is also presented and discussed.

关键词： Automotive aerodynamics Artificial intelligence Computer aided styling

SYNTHESIS AND OPTICAL PROPERTIES OF A NOVEL ORGANIC/INORGANIC HYBRID NONLINEAR OPTICAL POLYMER VIA SOL-GEL PROCESS

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2001年第4期19卷 421-427页

作者： Hong-xia Xi Zhong Li Zhao-xi Liang The Institute of Chemical Engineering South China University guangzhou 510640 China The Institute of Polymer Science, Zhongshan University guangzhou 510275, China S China Univ Inst Chem Engn Canton 510640 Peoples R China Zhongshan Univ Inst Polymer Sci Canton 510275 Peoples R China

A new organic/inorganic hybrid nonlinear optical (NLO) material was developed by the sol-gel process of an alkoxysilane dye with tetraethoxysilane. A NLO moiety based on 4-nitro-4 ' -hydroxy azobenzene was covalently bonded to the triethoxysilane derivative, i.e, gamma -isocyanatopropyl triethoxysilane. The preparation process and properties of the sol-gel derived NLO polymer were studied and characterized by SEM, FTIR,H-1-NMR, UV-Vis, DSC and second harmonic generation (SHG) measurement. The results indicated that the chemical bonding of the chromophores to the inorganic SiO2 networks induces low dipole alignment relaxation and preferable orientational stability. The SHG measurements also showed that the bonded polymer film containing 75 wt% of the akoxysilane dye has a high electro-optic coefficient (r(33)) of 7.1 pm/V at 1.1 mum wavelength, and exhibit good SHG stability, the r(33) values can maintain about 92.7% of its initial value at room temperature for 90 days, and can maintain about 59.3% at 100 degreesC for 300 min.

关键词： sol-gel process nonlinear optical material alkoxysilane dye dipole alignment relaxation chromophore

A Novel Sulfided Mo/C Catalyst for Direct Vapor Phase Carbonylation of Methanol at Atmospheric Pressure

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2003年第1期12卷 31-36页

作者： Feng PengDepartment of Chemical Engineering, South China University of Technology, guangzhou 510640, China Department of Chemical Engineering South China University of Technology Guangzhou 510640 China

The direct carbonylation of methanol, without any halide in the feed as apromoter, is presented. A series of Mo catalysts supported on activated carbon, γ-Al_2O_3 and SiO_2were prepared. The results show that the support greatly affects the Mo catalyst in the directvapor-phase carbonylation of methanol, and activated carbon is the best supports of the investigatedsupports. In addition, the relationships between adsorptions of NH_3 and CO and carbonylation ofmethanol were investigated. A novel sulfided Mo/C catalyst had high activity and selectivity for thevapor phase carbonylation of methanol to methyl acetate without the addition of a CH_3I promoter tothe feed. The reaction conditions were optimized at a reaction temperature of 573 K, a methanolconcentration of 23 mol% and a carbon monoxide space velocity of 3,000 L/(kg·h). Under theseoptimal conditions a methanol conversion of 50%, carbonylation selectivity of 80 rnol%, andspace-time yield of 8.0 mol/(kg·h) were obtained. The active phase of this novel sulfided Mo/Ccatalyst is the non-crystalline phase, and the active component is present as MoS_(2.5) on thesurface of the activated carbon.

关键词： methanol carbonylation sulfided catalyst molybdenum catalystsupport activated carbon heterogeneous catalysis