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81.
82.
4-(2-Hydroxy-phenyl)-but-3-en-2-one (1) was prepared via condensation of salicylaldehyde with acetone, and then reaction of the ketone 1 with thiosemicarbazide was accompanied by cyclization to give substituted pyrazole (2). Seven new 5-(2-hydroxy-phenyl)-3-methyl-4,5-dihydropyrazole-1-carbothioamide derivatives (3a–3g) were synthesized by the acylation of 2 and characterized by means of elemental analysis, infrared (IR), and 1H nuclear magnetic resonance (NMR). The compounds 3c, 3d, and 3g showed certain bactericidal activity against E. coli; while compound 3g showed certain bactericidal activity against P. vulgaris.
Translated from Chinese Journal of Applied Chemistry, 2006, 23(12): 1355–1358 [译自: 应用化学] 相似文献
83.
Zheng Yizhou Ding Xinhua Cen Peilin Yang Chein-Wen Tsao George T. 《Applied biochemistry and biotechnology》1996,57(1):627-632
Applied Biochemistry and Biotechnology - Lactic acid was produced by immobilizedLactobacillus delbreückii cells in a fixedbed reactor and then separated by a column packed with... 相似文献
84.
选择Skyme势E作为两核子间唯象相互作用,在Hartree-Fock理论中结合粒子数守恒方法处理同类核子间的对相互作用,计算了Li和Be的丰中子同位素的结构,计算表明中子间的对相互作用和双中子晕之间存在紧密的联系. 相似文献
85.
86.
In this paper we consider the Dirichlet problem to a degenerate elliptic equation in a domain whose interior contains a degenerate surface. By means of the method of expansion of Poisson kernel and applying the properties of special functions, we obtain the twice continuously differentiable solution of the problem on the entire space including infinity. 相似文献
87.
Xinhua Zhou Shangan Lin James C. W. Chien 《Journal of polymer science. Part A, Polymer chemistry》1990,28(10):2609-2632
Several CW–V catalysts were prepared by supporting VCl4 on Mg Cl2 with ethyl benzoate and CH–V catalysts prepared by reacting MgCl2.ROH, phthalic anhydride, and VCl4. These vanadium catalysts, activated with TEA (triethyl aluminum)/MPT (methyl-p-toluate) produce mainly (88–96%) refluxing n-heptane insoluble isotactic PP. The active site has $ k_{p,i} = 1580 \left( M {\rm s} \right)^{ - 1}, k_{tr,i}^{\rm A} = 2 \times 10^{ - 3} {\rm s}^{ - 1} , k_{tr}^{\rm H} = 3.8 \times 10^{ - 2} \left( {\rm torr} \right)^{ - {1 \mathord{\left/ {\vphantom {1 2}} \right. \kern-\nulldelimiterspace} 2}} {\rm s}^{ - 1}$ for the isospecific ones and $ k_{p,a} = 58 \left( M {\rm s} \right)^{ - 1} ,k_{tr,a}^{\rm A} = 3 \times 10^{ - 3} {\rm s}^{ -1}$ for the nonspecific sites. Catalyst of VCl3 supported on MgCl2 has comparable productivity as the VCl4/MgCl2 catalyst but catalyst of VCl2 supported on MgCl2 exhibit only one-ninth of the productivity. Extensive comparison has been made between the CW–V and the CW–Ti systems which revealed striking similarities between their polymerization behaviors. MgCl2 exerts profound influence on the stereochemical control of the vanadium ion on its activity for monomer coordination and insertion. 相似文献
88.
用屏栅电离室测量了入射中子能量为5.1MeV的58Ni(n,α)55Fe核反应的α粒子角分布,238U裂变电离室作中子注量率的测量,测得该能点58Ni(n,α)55Fe的总截面为(47.4±5.0)mb.用中国核数据中心推荐的理论计算程序UNF计算了在1—8MeV能区58Ni(n,p)58Co,58Ni(n,α)55Fe的反应截面和入射中子能量为5.1MeV的58Ni(n,α)反应角分布.理论和测量数据的比较说明,用复合核模型来描写该能点的角分布是可行的. 相似文献
89.
Pigment-grade anatase TiO2 particles (160 nm) were passivated using ultra-thin insulating films deposited by molecular layer deposition (MLD). Trimethylaluminum
(TMA) and ethylene glycol (E.G) were used as aluminum alkoxide (alucone) precursors in the temperature range of 100–160 °C.
The growth rate varied from 0.5 nm/cycle at 100 °C to 0.35 nm/cycle at 160 °C. Methylene blue oxidation tests indicated that
the photoactivity of pigment-grade TiO2 particles was quenched after 20 cycles of alucone MLD film, which was comparable to 70 cycles of Al2O3 film deposited by atomic layer deposition (ALD). Alucone films would decompose in the presence of water at room temperature
and would form a more stable composite containing aluminum, which decreased the passivation effect on the photoactivity of
TiO2 particles. 相似文献
90.
Cross-linked gelatin/nanoparticles composite coating on micro-arc oxidation film for corrosion and drug release 总被引:2,自引:0,他引:2
A composite coating which could control drug release and biocorrosion of magnesium alloy stent materials WE42 was prepared. This composite coating was fabricated on the surface of the micro-arc oxidation (MAO) film of the magnesium alloy, WE42, by mixing different degrees of cross-linked gelatin with well-dispersed poly(dl-lactide-co-glycolide) (PLGA) nanoparticles. The PLGA nanoparticles were prepared by emulsion solvent evaporation/extraction technique. Nano ZS laser diffraction particle size analyzer detected that the size of the nanoparticles to be 150-300 nm. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) was used to analyze the morphology of the nanoparticles and the composite coating. Potentiodynamic polarization and electrochemical impedance spectroscopy (EIS) were used to evaluate the corrosion behavior of the composite coating. Drug release was determined by ultraviolet-visible (UV-vis) spectrophotometer. The corrosion resistance of the composite coating was improved by preventing the corrosive ions from diffusing to the MAO films. The drug release rate of paclitaxel (PTX) exhibited a nearly linear sustained-release profile with no significant burst releases. 相似文献