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131.
Zai-Gang Luo Yu Zhao Chao Ma Xue-Mei Xu Xiao-Mei Zhang Nian-Yu Huang Hong-Qiu He 《中国化学快报》2014,25(5):737-740
A series of novel calix[4]arene derivatives incorporating two triazolyl 1 3-diketo subunits in alternate positions at the lower rim were synthesized and screened for HⅣ integrase inhibition activity.The chemical structures of these compounds were confirmed by means of1H NMR 13C NMR,and ESI-MS.Preliminary bioassays indicated that calix[4]arene derivatives proved to be more active than p-tertbutylcalix[4]arene derivatives.In particular,compound 4g presented the most potent integrase strand transfer inhibitory activity with an IC50value of 6.1 mmol/L. 相似文献
132.
133.
为了研究氢化非晶硅薄膜的稳定性,我们设计了一个在原子氢气氛中热退火的同时进行光诱导退火的实验(TLAH)。实验装置是由传统的微波电子回旋共振化学气相沉积系统改造而成为热丝辅助微波电子回旋共振化学气相沉积系统。为了对这一退火方法进行比较,对样品还进行了热退火、热退火同时进行光诱导退火。同时,为了定量地分析光电导衰退,我们假设光电导衰退遵循扩展指数规律:1/σph=1/σs-(1/σs-1/σ0)exp[-(t/τ)β],这里扩展指数参数β 和时间常数 τ 可从与 lnt 的线性关系中截距和斜率得到, 式中光电导饱和值σs可以通过在对数坐标系中表示的光电导和光照时间关系进行高斯拟合得到。实验结果显示:TLAH 方法可以提高氢化非晶硅薄膜的稳定性、改善其微结构和光电特性,同时还发现,光学带隙明显减小、荧光光谱显著地朝着低能方向移动。 相似文献
134.
Extraction of rare earth metal samarium by microemulsion 总被引:1,自引:0,他引:1
Chuan-Bo Xia Yan-Zhao Yang Xue-Mei Xin Song-Xian Wang 《Journal of Radioanalytical and Nuclear Chemistry》2008,275(3):535-540
The influence of the concentration of sodium oleate (NaOL), alcohol and the nature of the internal water phase on the water
content of microemulsion was studied. The effect of the concentration of NaOL, sodium stearate, alcohol, salting-out agent,
Alamine 336 added and of the contact time, volume ratio of the aqueous to microemulsion (R) and temperature on the extraction
yield of samarium was investigated. The result shows that the extraction of samarium is effective under well-defined conditions
utilizing WinsorII microemulsion systems. 相似文献
135.
硫(硒)杂多杯[4]芳烃合成及其络合性能研究 总被引:2,自引:0,他引:2
合成了下缘硫、硒杂杯[4]芳烃, 然后与杯芳烃片段2,6-二(溴甲基)-4-甲氧基-甲苯在NaH存在条件下缩合得到硫、硒杂多杯[4]芳烃5a和5b. 离子萃取实验表明硫、硒杂多杯[4]芳烃显著增加了对Ag+和Hg2+重金属离子的萃取效果. 相似文献
136.
N3H5异构化及构象分析 总被引:1,自引:0,他引:1
采用量子化学的方法, 对氮氢化合物N3H5所有可能的二面角变化进行松散势能面扫描, 获得了相应的能量和构象之间的关系, 研究了N3H5的异构化机理和构象的变化. 分子中的原子(AIM))理论计算得到的键临界点电荷密度的增大和减小,及其拉普拉斯值的正负变化, 可以清楚地反映构象转化过程中键的增长、断裂和新键生成的相关信息. 自然键轨道(NBO)理论分析表明, 立体排斥作用使分子能量升高, 而超共轭作用使分子能量降低, 它们对分子构象的相对稳定性起了重要作用. 相似文献
137.
The Au nanoparticles (Au NPs) modified interface has been fabricated by multi-potential step electrodeposition in this study. Based on the nano-Au interface, we have proposed an electrochemical approach to detect the cancer cell numbers sensitively with a detection limit of about 500 cells. More interestingly, the drug sensitive leukemia K562 cells and drug resistant leukemia K562/adriamycin could be electrochemically distinguished on the interface by the oxidation potential, which did not show any evident differences on the bare electrode. These results indicate the promising application of this nano-interface for constructing the unlabeled potential-discriminative cell biosensors. 相似文献
138.
What do we need for a superhydrophobic surface? A review on the recent progress in the preparation of superhydrophobic surfaces 总被引:10,自引:0,他引:10
Superhydrophobic surfaces have drawn a lot of interest both in academia and in industry because of the self-cleaning properties. This critical review focuses on the recent progress (within the last three years) in the preparation, theoretical modeling, and applications of superhydrophobic surfaces. The preparation approaches are reviewed according to categorized approaches such as bottom-up, top-down, and combination approaches. The advantages and limitations of each strategy are summarized and compared. Progress in theoretical modeling of surface design and wettability behavior focuses on the transition state of superhydrophobic surfaces and the role of the roughness factor. Finally, the problems/obstacles related to applicability of superhydrophobic surfaces in real life are addressed. This review should be of interest to students and scientists interested specifically in superhydrophobic surfaces but also to scientists and industries focused in material chemistry in general. 相似文献
139.
采用水热氧化法制备镍钛合金(NiTi)固相微萃取纤维.实验结果表明,在80℃ 的H2 O2溶液中,直接氧化NiTi纤维基体可在其表面原位生长纳米多孔氧化镍/氧化钛复合涂层,其中氧化镍含量显著高于氧化钛含量.与高效液相色谱-紫外检测器(HPLC-UV)检测技术联用,考察了所制备NiTi纤维对典型芳香族化合物的萃取性能.结果表明,富Ni复合氧化物涂层对多环芳烃(PAHs)表现出良好的萃取选择性.在优化实验条件下,方法的线性范围为0.1~400.0 ng/mL,相关系数大于0.999,PAHs的检出限为0.026~0.056 ng/mL.对于50 ng/mL加标水样,单支NiTi纤维日内和日间测量的相对标准偏差(RSDs)分别为4.8%~6.2%和5.4%~6.5%(n=5),使用5支不同批纤维测量的RSDs为6.4%~8.4%.本方法适用于环境水样中PAHs的富集和测定,相对回收率为89.9%~108.5%,RSDs<8.1%.而且,NiTi纤维机械强度高,化学稳定性好,制备过程精密可控. 相似文献
140.
Kai-Qing Ma Yan-Hong Miao Xiao-Xia Gao Jian-Bin Chao Xiang Zhang Xue-Mei Qin 《中国化学快报》2017,28(5):1035-1038
An efficient route to the natural products bupleurynol and its analog (RB-2), isolated from Bupleuri Radix, was established based on versatile intermediate (15). In this synthetic route, Sonogashira and Cadiot-Chodkiewicz coupling as well as Julia-Kocienski olefination are utilized as key steps. The highly efficient synthetic route provides opportunities to explore the biological behavior of bupleurynol and RB-2. 相似文献