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931.
Shi Liang HUANG Yi LUO Zhi Shu HUANG Xian Zhang BU Pei Qing LIU Lin MA Yue Ming LI Albert S. C. CHAN Lian Quan GU 《中国化学快报》2006,17(6):769-772
Mansonone compounds represent a series of naturally occurring o-quinones mainly isolated from the heartwood of Mansonia Altissima1 and Ulmus Glabra2. Mansonone F contained oxaphenalene skeleton which was a relatively novel structure and rarely existed in … 相似文献
932.
米非司酮的吸附伏安特性 总被引:1,自引:0,他引:1
在PH7.0Britton-Robinson缓冲溶液中,米非司酮(Mifepristone,RU486)在汞电极上有2个不可逆的线性扫描还原峰,峰电位分别为-1.23V和-1.68V。本文探讨了第一峰的电化学行为。 相似文献
933.
Boris U. Stambuk Mary Ann Franden Arjun Singh Min Zhang 《Applied biochemistry and biotechnology》2003,106(1-3):255-263
The kinetics and regulation of d-xylose uptake were investigated in the efficient pentose fermentor Candida succiphila, and in Kluyveromyces marxianus, which assimilate but do not ferment pentose sugars. Active high-affinity (K
m
∼ 3.8 mM; V
max ∼ 15 nmol/[mg·min]) and putative facilitated diffusion low-affinity (K
m
∼ 140 mM; V
max ∼ 130 nmol/[mg·min]) transport activities were found in C. succiphila grown, respectively, on xylose or glucose. K. marxianus showed facilitated diffusion low-affinity (K
m
∼ 103 mM; V
max ∼ 190 nmol/[mg·min]) transport activity when grown on xylose under microaerobic conditions, and both a low-affinity and an
active high-affinity (K
m
∼ 0.2 mM; V
max ∼ 10 nmol/[mg·min]) transport activity when grown on xylose under fully aerobic conditions. 相似文献
934.
Lingyan Zhang Ruo Yuan Xiaoqing Huang Yaqing Chai Shurui Cao 《Electrochemistry communications》2004,6(12):1222-1226
A novel potentiometric immunosensor for detection of Japanese B encephalitis vaccine was developed by immobilizing antiserum of Japanese B encephalitis on nano-Au/polymerized o-phenylenediamine (o-PDA) film on the platinum (Pt) electrode. The performance and factors influencing the performance of the resulting immunosensor were studied. The immunosensor showed a specific response to Japanese B encephalitis vaccine in the range 1.1 × 10−8 to 2.0 × 10−6 lgpfu/ml (plaque forming unit) with a detection limit of 6 × 10−9 lgpfu/ml. The correlation coefficient is 0.9986. The incubation time, incubation temperature, pH, reproducibility and stability of the immunosensor were also studied. The present work supplied a promising test method for biological products. 相似文献
935.
Hainer?Wackerbarth Rodolphe?Marie Mikala?Grubb Jingdong?Zhang Allan?G.?Hansen Ib?Chorkendorff Claus?B.?V.?Christensen Anja?Boisen Jens?UlstrupEmail author 《Journal of Solid State Electrochemistry》2004,8(7):474-481
We provide a comprehensive study of single- (ss) and double-strand (ds) oligonucleotides with either 25 or 10 bases or base pairs (bp) immobilized on polycrystalline and single-crystal Au(111) surfaces. The study is based on X-ray photoelectron spectroscopy, cyclic and differential pulse voltammetry, interfacial capacitance data, and electrochemical scanning tunnelling microscopy (in situ STM). The sequences used were the 25-bp sequence from the BRCA1 gene (25-mer), while the 10-bp oligonucleotides contained solely linear adenine and thymine sequences. The oligonucleotides were modified by the dimethoxytrityl group (DMT) via a disulfide group [DMT-S-S-ss25-mer and DMT-S-S-ds(AT)10], a pure disulfide group (A10-S-S-T10), or a thiol group [HS-ss25-mer and HS-ds-(AT)10], all via a hexamethylene linker. The overall pattern suggests strategies for controlled adsorption of DNA-based molecules and recognition of complementary strands or other molecules. 相似文献
936.
937.
烟酸对酸性硫酸盐体系铜电沉积的影响 总被引:2,自引:0,他引:2
对溶液A: 0.8 mol•L-1硫酸铜,0.6 mol•L-1硫酸,5.0×10-5 mol•L-1氯离子,1.0×10-4 mol•L-1聚乙二醇的溶液,溶液B:在溶液A中加入2.0×10-2 mol•L-1烟酸,pH为0.5,运用循环伏安和计时安培法研究玻碳电极上铜的电沉积行为.结果表明,铜的电沉积过程经历了晶核形成过程,其电结晶按瞬时成核和三维生长方式进行.烟酸的加入对铜的电沉积具有阻化作用,但不改变铜的电结晶机理.沉积层的X射线衍射表明Cu为面心立方结构,在烟酸存在下沉积层出现(220)高择优取向,这可能是烟酸在Cu(220)晶面上发生强烈吸附作用的结果. 相似文献
938.
939.
Simmonds等报道异戊烯基化的查耳酮和黄烷酮对昆虫具有拒食活性[1],Echeverri等发现,从植物Passiflorafoetida树脂中分离到的4,7-二甲氧基莰非醇(1)在很低的浓度下(40μg/g)对昆虫Dionejuno的幼虫也具有... 相似文献
940.
Low permittivity ceramic substrates with a sandwich structure consisting of a porous, fiber-reinforced SiO2 core and two thin polymer plates were fabricated by sol-gel processing, and polymer infiltration. The rheological behavior of an aqueous colloidal SiO2 sol, containing short SiO2 fibers was studied as a function of particle loading, fiber loading and gelation time. Short SiO2 fibers were introduced to limit drying shrinkage and thus minimize substrate cracking during drying. After the psuedoplastic sol was tape cast and sintered at 1150°C for 2 h, a polyimide solution was infiltrated into the porous SiO2 core. Permittivities ranging from 1.81 to 3.08 could be obtained by using 32–42% SiO2, 5–50% polyimide and 63 to 8% porosity. The substrate strength was increased from 1.93 MPa to 3.83 MPa after polyimide infiltration. 相似文献