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111.
Recently, the studies on the interaction of DNA with small molecules have been attracting much interest1-6. These researches not only gave the important information about thermodynamics and kinetics, but also can prompt the combination between the electrode substances and biomacromolecule with super catalysis and sensor character. It is of great significance in understanding energy conversion and metabolism in live body, biomolecular structure, various physical and chemical characters for e… 相似文献
112.
Jian Guo DENG Xiao Bin DING Yu Xing PENG* Albert S. C. CHAN* Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu Open Laboratory of Chirotechnology Department of Applied Biology Chemical Technology 《中国化学快报》2001,(11)
Among various conducting polymers, polyaniline (PANI) is a unique and promising candidate for practical applications because it is not only highly stable in air and in some solvents, but also exhibits dramatic changes in its electronic structure and physical properties in protoactivate state1,2,3. The carbon nanotubes (CNTs) have been proven to possess exotic properties, such as high mechanical strength, flexibility and electric conductivity. The study of carbon-based nanostructures and ma… 相似文献
113.
Jian Feng GE Li Fen ZHANG Zong Xuan SHEN Ya Wen ZHANG* Department of Chemistry Chemical Engineering Suzhou University Suzhou Department of Material Engineering Suzhou University Suzhou 《中国化学快报》2001,(7)
Mercaptoalcohols are a rare class of natural products. Some optically active mercaptoalcohols have been used as catalysts in asymmetric reduction of prochiral Ketone1,2. In this letter, we report the synthesis of a new optically active (-mercaptoalcohols, (R)-1,1-diphenyl-2-mercapto-3-methyl-1-butanol 7, from L- valine.Our first attempt is showed in Scheme 1. According to literature's method L-valine was converted to (S)-2-Hydroxy-3-methylbutanoic acid 21,2. 2 was treated with MeOH/SOCl2… 相似文献
114.
Sai Jing ZHENG Xiang Qin LIN* Department of Chemistry University of Science Technology of China Hefei 《中国化学快报》2001,(7)
Interactions of DNA with various molecules are interesting because of its importance in gene expression process of living cells. Several models for the interaction between DNA and some small molecules have been proposed1-4. We are interested in the possibility of the interaction between DNA/RNA and neurotransmitters, such as dopamine and epinephrine, because these species are very important substances for keeping normal physiological functions of brain and neuro system. However, no report… 相似文献
115.
Baker's Yeast Mediated Reduction of Optically Active Diketone 总被引:1,自引:0,他引:1
Xiao Lei GAO Gang ZHOU Yu Kun GUAN Wei Dong LI Yu Lin LI* National Laboratory of Applied Organic Chemistry Institute of Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2001,(4)
Baker's yeast (BY) mediated reduction of synthetic substrate is a useful method for preparing chiral intermediate in synthesis chemistry1,2, because it is readily available and inexpensive. The selectivity is generally predicted by Prelog rule3, that is, a hydride is transferred to the re face of the prochiral ketone.The baker's yeast mediated reduction of bicyclic diketones was previously reported by several groups4-6, but to our knowledge, no application of this reduction to sesquiter-pene-… 相似文献
116.
Cheng Feng YE Ze Fu ZHANG Wei Min LIU* State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 《中国化学快报》2001,(4)
In recent years, many efforts were focused on the preparation and characterization of phosphazene which contained a framework of alternating phosphorous and nitrogen atoms with two substituent groups attached to each phosphorous atom1. It is noticeable that cyclophosphazene, especially hexaaryloxyphosphazene and perfluoroaryloxyphosphazene exhibit excellent thermal and chemical stability which can be used as fireproof materials, high temperature lubricants, vacuum pump oils and hard disk surfac… 相似文献
117.
Preparing Nano-ZnS by Solid State Reaction at Room Temperature 总被引:3,自引:0,他引:3
Xiao Lin SUN Guang Yan HONG* Laboratory of Rare Earth Chemistry Physics Changchun Institute of Applied Chemistry Changchun 《中国化学快报》2001,(2)
Solid-state reaction has been studied for a long time1-3. In recent years, some researches have been focused on the preparation of coordination compounds at low temperatures or even at room temperature4-5. In this letter, preparation of ZnS nanoparticles by using solid state reaction at room temperature is reported.ZnS nanoparticles were prepared as follows: Zn(CH3COO)2 and Na2S?9H2O, in equal molar ratio, were ground in agate mortar. After 20 minutes, the powder was washed by water and … 相似文献
118.
YIN Xue-feng~ 《高等学校化学研究》2001,17(3):264-270
The suitability of 1-nitroso-2-naphthol(NN) as a complexing agent for on-line preconcentration of cobalt eluted on the C_(18) microcolumn by means of the FI-FAAS system was tested. Various parameters affecting the complex formation and its elution were optimized. A 2.3×10~(-3) mol/L reagent solution and the aqueous sample solution acidified with 0.1% (volume fraction) nitric acid were on-line mixed (6.4 mL/min) on a reaction coil set at (65±1)℃ and flowed through the microcolumn for 30 s. The pH of the mixed solution was adjusted to 3—4 with HNO_3(1 mol/L) or NaOH(1 mol/L). The adsorbed complexes in the microcolumn were eluted into the nebulizer of FAAS in 10 s with ethanol acidified with 1% HNO_3(3.0 mL/min). A good precision(1.6% for 100μg/L Co(Ⅱ), n=10), a high enrichment factor 17.2, with detection limit (3σ) 3.2μg/L, and sample throughput (90 h~(-1)) were obtained. The method was applied to the certified reference materials(CRMs), NBS-362 and NBS-364, for the determination of cobalt and the results were in good agreement with the certified values. 相似文献
119.
HU Jing-bo LI Qi-long * * {Department of Chemistry Beijing Normal University Beijing P.R.China) 《高等学校化学研究》2001,17(4):362-367
In a 0. 10 mol/L HAc-NaAc buffer solution (pH = 4. 59), a sensitive reduction peak of bleomycin was observed by linear sweep voltammetry at a Co/GC ion implantation modified electrode. The peak potential was-0. 73 V(iw. SCE). The peak current was proportional to the concentration of bleomycin over the range of 5.0 × 10-8-1.0× 10-6 and 1.0× 10-6-1. 0 × 10-5 mol/L with a detection limit of 2.0 × 10-8 mol/L. The electrochemical behavior of the reduction peak of bleomycin at the Co/GC modified electrode was studied by linear sweep and cyclic voltammetry and applied to the determination of bleomycin in urine. This method is simple, rapid and reliable. The reduction process is quasi-reversible. The experiments of AES and XPS showed that Co was surely implanted into the surface of GCE and the depth distribution of Co was in good agreement with Gooses normal distribution; the implanted Co at GCE improved the electrocatalytic activity. 相似文献
120.
The kinetic procedure of the unfolding of lysozyme induced by the reduction of disulfide was monitored by the time-resolved ESI-MS with a sheath liquid assistant electrospray interface. It was found that the reduction process for the eight disulfides had a less difference in the reaction time after denatured treatment. In addition, the alkylation of the reduced free thiols was much slower than the reduction procedure. An artifact peak produced by the CID fragmentation in the mass spectra was identified and the possible mechanism of the Hofmann elimination reaction was proposed. 相似文献