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61.
62.
This article gives characterizations of generalized derivations with skew nilpotent values on noncommutative Lie ideals of a prime ring. The results simultaneously generalize the ones of Herstein, Lee and Carini et al. 相似文献
63.
本文用空间解析几何方法,推导了在一般非平行斜入射光条件下,裂纹体表面所形成的反射焦散线和初始曲线的方程.分析了倾斜入射光造成的焦散线畸变,给出了这种畸变造成的裂端应力强度因子测量误差的解析表达式. 相似文献
64.
用均匀化理论分析蜂窝结构的等效弹性参数 总被引:8,自引:3,他引:8
在线弹性范围内,根据均匀化理论,并结合有限元方法推导出适用于二维周期性结构的均匀化的有限元格式(Homo FEM),计算出不同相对密度下的规则蜂窝结构的等效弹性模量Ee和泊松比νe.同时,利用蜂窝结构的代表胞元模型,用常规的有限元方法(FEM)模拟计算出相应的等效弹性参数.最后将两种数值计算结果与己有的理论公式进行了比较和分析讨论.结果表明:在考察的相对密度全场范围内(0~0.4),HOmO FEM得到的蜂窝结构的 Ee和νe 与 FEM使用平面实体单元模拟计算得到的结果一致吻合,反映出 Homo FEM数值方法的客观准确性和可行性.而 Gibson公式和 W-K得到的等效弹性模量值 Ee只是在较小相对密度的情况下(小于0.15)与数值计算结果吻合.当结构的相对密度较大时,必须考虑胞棱附近区域由应力集中导致的复杂的应力和应变分布的影响. 相似文献
65.
66.
We have synthesized water-dispersible CdTe quantum dots (QDs) capped with thioglycolic acid. Their quantum yield is higher than 54%. A sensitive electrochemiluminescence (ECL) method was established based on the modification of the composite of the QDs, carbon nanotubes and chitosan on indium tin oxide glass. The sensor displays efficient and stable anodic ECL which is quenched by dopamine. A respective sensor was designed that responds to dopamine linearly in the range of 50?pM to 10?nM, and the detection limit is 24?pM. Dopamine was determined with this sensor in spiked cerebro-spinal fluid with average recoveries of 95.7%. Figure
The CdTe quantum dots have been synthesized and therefore developed an electrochemiluminescent sensor based on immobilizing its composite with carbon nanotubes and chitosan on indium tin oxide glass. The sensor responded toward dopamine linearly in the range of 50?pM to 10?nM with a detection limit of 24?pM. 相似文献
67.
We report on an electrochemiluminescent (ECL) sensing technique for the detection of the hybridization between oligonucleotides. A glassy carbon electrode was first functionalized with a composite prepared from gold nanoparticles and carbon nanotubes, and a sensor was then constructed by immobilizing the probing oligonucleotide. The ECL of luminol acts as the sensing signal. It is quenched, to a different degree, by the hybridized double strands of the oligonucleotide depending on the match status. The slope of the ECL response as a function of the status of hybridization drops with increasingly matched hybridization. The response is attributed to the interaction between luminol and the strands of oligomers, and also related to the reduction of reactive oxygen species. Figure
An electrochemiluminescent sensing technique is developed by immobilization of probing oligonucleotide on a previously functionalized electrode with composite of carbon nanotubes and gold nano-particles. The quenching efficiency for ECL of luminol upon the hybridized status of target oligonucleotide with probing one had been detected where the mismatch ratio was distinguishable. ECL response for luminol on (a) CNTs/AuNP/GCE, (b) probe-strand/CNTs /AuNP/GCE, (c) 1-3 hybridized strands/CNTs/AuNP/GCE and (d) 1-2 hybridized strands/CNTs/AuNP/GCE. 相似文献
68.
GU Xin-quan CHEN Yan-ping HU Ting-ting LU Xiu-hua LI Xi-qian DU Xiao-hui CAO Xia WANG Wei-hua XU Zhong-gao .China-Japan Union Hospital of Jilin University Changchun P.R.China .College of Chemistry Jilin University Changchun .College of Pharmacy Changchun 《高等学校化学研究》2011,(4):584-588
This paper studies the extraction and identification of ginsenoside Re from ginseng fruits and investigates the effect and mechanism of ginsenoside Re of protecting acute renal ischemia-reperfusion injury in rats.Having been smashed,the ginseng fruits were ultrasonically extracted twice with 95% ethanol for 30min each.Having been concentrated,the solution was dissolved with distilled water and separated by two-column chromatography,of which one was packed with macroporous resin D4020,and the other was packe... 相似文献
69.
REN Lin WANG Dian SUN Gui-ting NIU Li-gang YANG Han SONG Jun-feng State Key Laboratory on Integrated Optoelectronics College of Electronic Science Engineering Jilin University Changchun P. R. China 《高等学校化学研究》2011,27(1):113-116
The present paper covers the various photonic crystals(PhCs) structures mimicking real atom-lattice structures in electronic crystals by using the femtosecond laser-induced two-photon photopolymerization of SU-8 resin. The bandgap properties were investigated by varying the crystal orientations in <111>, <110> and <100> of diamond-lattice PhCs. The photonic stop gaps were present at λ=3.88 μm in <111> direction, λ=4.01 μm in <110> direction and λ=5.30 μm in <100> direction, respectively. In addition, defect... 相似文献
70.
WEI Wei LI Xu-wen SHI Xiao-lei ZHOU Hong-yu YANG Rui-jie ZHANG Han-qi JIN Yong-ri College of Chemistry Jilin University Changchun P. R. China 《高等学校化学研究》2011,27(1):23-27
Matrix solid-phase dispersion(MSPD) was developed for the extraction of four alkaloids, including aconitine, mesaconitine, hypaconitine and deoxyaconitine, from the roots of Aconitum kusnezoffii Reichb. The determination of the analyte was carried out by high performance liquid chromatography with UV detection. The alkaline alumina was used as sorbent. The mixture of acetonitrile and water was used as elution solvent. Several extraction parameters, such as type of sorbent, the ratio of sample to solid suppo... 相似文献