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911.
912.
Three kinds of Ni-P electroless coatings were prepared in nickel sulphate solution at different pH values of 4.5,5.5 and 6.5 with the purpose of ascertaining the influence of pH value on microstructure,internal stress statue and thermal stability of the coatings.Laser curvature(LC) method was used to measure the residual stress level in the coatings.Scanning electronic microscopy(SEM) and transmission electronic microscopy with energy dispersive spectrum(TEM/EDS) were used to examine the surface morpholo... 相似文献
913.
A new zinc acetate catalyst which was prepared from modified activated carbon exhibited extreme activity towards the synthesis of vinyl acetate.The activated carbon was modified by nitric acid,vitriol and peroxyacetic acid(PAA).The effect on specific area, structure,pH and surface acidity groups of carriers by modification was discussed.Amount of carbonyl and carboxyl groups in activated carbon was increased by peroxyacetic acid treatment.The productivity of the new catalyst was 14.58%higher than that of... 相似文献
914.
A new-type UV light source(206 nm) was explored for the degradation of organic pollutants in wastewater for the first time.The degradation performances of triphenyltin chloride(TPTCl),dimethyl phthalate(DMP),as well as rhodamine B(RhB) were investigated.The results indicated that removal efficiency of 50 mg/L RhB,60 mg/L DMP and 120 mg/L TPTCl can reach 88.6%, 92.5%and 89.4%for 60 min,50 min and 75 min,respectively.By comparison of removal efficiency,we found 206 nm is superior to 253.7 nm UV in wastewat... 相似文献
915.
纳米线为准一维纳米材料[1],因其具有优异的光学、电学及力学性能而引起人们的极大关注.它的制备方法有许多种,如分子束外延法、光刻法、CVD法、模板法[2]等.其中模板法由于具有实验装置简单,操作容易,形态可控,适用面广等特点而成为纳米材料合成领域的一大焦点.常用的模板有:有序空洞阵列氧化铝模板、含有孔洞无序分布的高分子模板、纳米洞孔玻璃模板.其中阳极氧化铝(AAO)模板具有孔径均一、排列有序、孔密度高、热稳定性好且孔径大小可控等优点,成为模板合成法中最常用模板之一[3]. 相似文献
916.
重组质粒pIRES-EGFP-BCL 11B电转染幼稚T细胞的可视化研究 总被引:1,自引:1,他引:0
将BCL 11B基因插入pIRES-EGFP构建重组质粒真核表达载体pIRES-EGFP-BCL 11B,采用电转染法将重组质粒转入人幼稚T细胞,转染24 h后,用原子力显微镜(AFM)观察转染前后细胞的表面形态以及生物物理性质的变化.转染72 h后,用CCK-8试剂检测幼稚T细胞的增殖情况.分别对空转的幼稚T细胞组、空载体转染组(pIRES-EGFP naked plasmid)、重组载体转染组(pIRES-EGFP-BCL 11B recombinant vector)、无电转无质粒的幼稚T细胞组进行实验.结果表明,4组幼稚T细胞的体积、高度、半宽度、粗糙度、表面颗粒大小等参数发生了变化,细胞杨氏模量以及细胞硬度也呈现很大变化,CCK-8结果显示,重组质粒pIRES-EGFP-BCL 11B电转染人幼稚T细胞后影响细胞的增殖. 相似文献
917.
WANG Hui-ping XU Wen-guo ZHANG Hong-xing . State Key Laboratory of Theoretical Chemistry 《高等学校化学研究》2009,25(3)
The molecular structures and electron affinities of 5-and 6-halouracils(XU,X=F,Cl,Br) were determined by means of five different density functional methods. The basis set used in this work is of double-ζ plus polarization(DZP) quality with additional diffuse s-and p-type functions,denoted DZP++. The geometries were fully optimized with each density functional theory(DFT) method,and discussed. Three different types of the neutral-anion energy separations reported in this work are the adiabatic electron affin... 相似文献
918.
919.
920.
Surface reconstruction from unorganized data points is a challenging problem in Computer Aided Design and Geometric Modeling. In this paper, we extend the mathematical model proposed by Juttler and Felis (Adv. Comput. Math., 17 (2002), pp. 135-152) based on tensor product algebraic spline surfaces from fixed meshes to adaptive meshes. We start with a tensor product algebraic B-spline surface defined on an initial mesh to fit the given data based on an optimization approach. By measuring the fitting errors over each cell of the mesh, we recursively insert new knots in cells over which the errors are larger than some given threshold, and construct a new algebraic spline surface to better fit the given data locally. The algorithm terminates when the error over each cell is less than the threshold. We provide some examples to demonstrate our algorithm and compare it with Jiittler's method. Examples suggest that our method is effective and is able to produce reconstruction surfaces of high quality.AMS subject classifications: 65D17 相似文献