共查询到20条相似文献,搜索用时 15 毫秒
1.
Methylaluminoxane (MAO) is one of the most important cocatalysts of metallocene catalysts. The yield and activity of MAO is low when using Al2(SO4)3 nH2O and other inorganic hydrates to synthesize methylaluminoxane. The repeatability of this reaction is not good. The product cost is very high because one of the raw materials (Trimethylaluminium, TMA) to prepare MAO is very expensive. In addition, on standing, MAO toluene solution tends to gel. Gelled MAO can not be used to prepare su… 相似文献
2.
Chao Jie WANG Jian Hong WANG Ying GAN Zhi Yong CHEN Gang Jun DU Jin ZHAO 《中国化学快报》2006,17(10):1301-1304
Chemotherapy is one of the most important treatments of cancer, however, clinical use of conventional anticancer drugs is often limited by their side effects such as toxicity for normal tissues and multidrug resistance of tumor cells1, 2. Because of the s… 相似文献
3.
Qing Fang CHENG Xing You XU Ming Yan WANG Jun CHEW Wei Xing MA Xu Jie YANG 《中国化学快报》2006,17(7):887-890
The reductive coupling of carbonyl compounds catalyzed by the transition metal is an important group of carbon-carbon bond forming reaction. The pinacol coupling reaction of aldehydes is one of the most efficient methods for synthesis of vicinal diols1. L… 相似文献
4.
Control on Crystal Forms of Ultrafine Barium Carbonate Particles and Study on its Mechanism 总被引:4,自引:0,他引:4
HUO Ji-Chuan ② LIU Shu-Xin YANG Ding-Ming WANG Hai-Bin 《结构化学》2005,24(11):1290-1297
1 INTRODUCTION Barium carbonate is one of the important che- mical materials as well as one of the most important barium salts. Its application covers multitudinous in- dustries and fields such as building material, meta- llurgy, electron, chemical industry and so on[1]. With the fast development of science and technology, it is becoming more and more demanding with barium carbonate’s quality, and more and more scientific workers do researches on the control of Barium car- bonate’s crys… 相似文献
5.
Lian De ZHU Ying Xiu LI Guo Yi ZHU* State key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 《中国化学快报》2002,13(11)
Histidine is one of the necessary basic amino acids in biological bases, which often controls the catalytic activity of enzymes and acts in holding the higher structure of proteins. Furthermore, it is also an important ingredient in pharmaceutical preparations used for treatment of hetpatosis and nephropathy. Therefore, the determination of histidine in biological fluids and pharmaceutical preparations is of great importance. Various methods have been proposed for the detection of histidine … 相似文献
6.
ε-Caprolactam 《高等学校化学研究》2008,24(2):246-248
ε-Caprolactam(CL or CPL) is one of the most important intermediates used in polymer industry for the production of several million tons of nylon-6 every year^[1]. All current commercial processes for the production of caprolactam are based on either benzene or tolueneI21. Caprolactam is synthesized by the Beckmann rearrangement of cyclohexanone oxime with fuming sulfuric acid or sulfuric acid as the reaction medium, and cyclohexanone oxime is produced by the reaction between cyclohexanone and hydro- xylamine(only one exception is the Toray PNC process). 相似文献
7.
Xiu Hui LIU Yan ZHANG Guo Fang ZUO Xiao Quan LU*College of Chemistry & Chemical Engineering Northwest Normal University Lanzhou 《中国化学快报》2006,17(5):657-660
Epinephrine (EP) is one of the most important neurotransmitters in mammalian central nervous systems, existing in the nervous tissue and body fluid in the form of large organic cations, and controlling the nervous system in the series of biological perfor… 相似文献
8.
Xiao Guang XIE* Xue Mei GAO Shi Xi LUI Huai CAO Shu Shan DAI Department of Chemistry Yunnan University Kunming Modern Biological Center Yunnan University Kunming 《中国化学快报》2001,(6)
The theoretical study of small molecules containing transition metal atoms is one of the most active areas in quantum chemistry1. Very extensive studies have been done on first and second row transition metal hydrides2,3, oxides4-6 and the transition metal dimers7-9. But theoretical studies on the third row transition metal compounds are more scarce.Platinum is an important element for catalytic reactions, and the knowledge of the interaction between Pt and C/N atom is basic, but important fo… 相似文献
9.
Shu Guo WANG Jin Lin LI 《中国化学快报》2006,17(2):221-224
Water polluted by toxic metals remains an important environmental issue, and there hasrecently been a growing interest in the research of materials capable of removing toxicmetal ions from contaminated water. Mercury is one of the heavy metal ions that ha… 相似文献
10.
Liu Hua XU Hu ZHENG Ling Ling WENG 《中国化学快报》2005,16(11):1434-1436
Bone tumor, as a common disease, is treated by surgical resection, radiotherapy and chemotherapy. Chemotherapy is one of the most important treatment, however, a major problem of chemotherapy is lack of selectivity of cytotoxic drugs. Although many attempts have been made to increase the selectivity of therapeutic drugs for the bone diseases, such as osteoporosis, paget’s, hypercalcemia and bone metastases by conjugating them with targeting carriers1-4, there are still no bone-targeting agent… 相似文献
11.
Xiao Ling WANG Wei JIAO Xun LIAO Shu Ling PENG Li Sheng DING 《中国化学快报》2006,17(7):916-918
The roots of Paeonia lactiflora Pall. is one of the most important traditional Chinese medicines, which has been used for the treatment of dizziness, spasm, menstrual disorder, spontaneous and night sweating, and as a general analgesic1. Chemical constitu… 相似文献
12.
1 INTRODUCTION Cyanide, CN, is an important free-radical mole-cule of one carbon chemistry, organic chemistry, free-radical chemistry and cosmochemistry. And the im-portant industrial processes, such as the Andrussovreaction, depend on the reactivity of CN bond[1]. Thechemistry of cyanide is also important in the surfacechemistry of a number of C- and N-containing sys-tems[1, . During the past decade, the adsorption of 2]CN and CN-containing molecules on transition metalsurfa… 相似文献
13.
Hong Liu LIA Huai Jun ZHU Feng Yi LI 《中国化学快报》2006,17(6):803-806
Hydrosilylation is one of the most important reactions for synthesis of modified siliane and polysiloxane. Since the discovery by Speier et al. in 1957 that hexachloroplatinic acid is a potent catalyst even under ambient conditions1, Pt complexes have bec… 相似文献
14.
正Carbon-carbon bond formation is the core of organic synthesis.Transition metal-catalyzed cross-coupling reaction between organohalides and organometallic reagents is one of the most important and straightforward methods for construction of C-C bonds.The catalytic cross coupling between two sp~2-carbon centers,e.g.,aryl-aryl cross- 相似文献
15.
JING Liqiang YUAN Fulong HOU Haige XIN Baifu CAI Weimin & FU Honggang . The Key Laboratory of Physical Chemistry School of Chemistry Material Sciences Heilongjiang University Harbin China . Department of Environmental Sciences Engineering Harbin Institute of Technology Harbin China 《中国科学B辑(英文版)》2005,48(1):25-30
ZnO is one of important semiconductor materials,applied widely in the fields such as the cerams, piezo-electric sensors, catalysts and luminescence apparatus.ZnO nanoparticles not only are ideal materials to pre-pare newly electronic apparatus[1], but als… 相似文献
16.
LI Hongjun ZHU Tong DING Jie CHEN Qi & XU Bingye State Key Joint Laboratory of Environment Simulation Pollution Control College of Environmental Science Peking Uni- versity Beijing China 《中国科学B辑(英文版)》2006,49(4)
Sodium chloride is the major constituent of sea salt particles in atmospheric environment, with an esti- mated annual contribution of 1012 kg of sea salt parti- cles to the atmosphere[1]. Many studies have shown a significant chloride deficit in these particles when compared to bulk seawater[2,3]. This deficit has been attributed to reactions with NOx and SO2[4]. Simulta- neously, NO2 is one of the main pollutants of mobile vehicles. Reaction (1) may be particularly important to the atmosph… 相似文献
17.
Wan Xuan ZHANG Xue Long HOU 《中国化学快报》2006,17(8):1037-1040
Amines are prevalent in drugs, natural products, materials, catalysts etc.. The reaction of C=N in imines is one of the most important approaches to synthesize amines1. Sulfinyl group as an excellent chiral auxiliary and activator of the C=N bond for nucl… 相似文献
18.
1 INTRODUCTION Manganese is one of several first-row transition metal elements that have been found to play an important role in most biological systems. Perhaps the best known is in the process of photosynthesis during which water is oxidized to yield dioxygen, and it is generally believed that the process is related to a tetranuclear manganese cluster[1]. Other aspects of biological chemistry of manganese, such as three mononuclear manganese enzymes: manganese superoxide dismutase, per… 相似文献
19.
Cai Qin QIN Ling XIAO Yu Min DU* Xiao Hai GAO Department of Environmental Science Wuhan University Wuhan Hubei Cancer Institute Wuhan 《中国化学快报》2002,13(3)
Selenium is a biologically important element and essential for life1. Selenium deficiency causes severe degenerative disease, such as Kesan cardiomyopathy, and has been implicated in increasing the incidence of human cancer and some chronic ailment as well as ageing. Administration of selenium compounds such as sodium selenite protects animals against carcinogens and markedly reduces the incidence of various neoplasms in human2. Chitosan is one of the most abundant glycans in nature and its… 相似文献
20.
High performance liquid chromatography-mass spectrometry is one of the most commonly used strategies for lipid analysis. The development of versatile chromatographic stationary phases to meet the increasing demands for separation of complex lipids is very important. Styrene-maleic acid(SMA) copolymer is an amphiphilic polymer, which has been proven to have the ability to solubilize lipid molecules of various structures. In this study, styrene-maleic anhydride copolymer coated silica was first pr... 相似文献