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81.
Li Chao Yin Siyu Zhou Hongbo Zhang Yajiao Li Yongxiu Chen Yufeng 《Journal of Sol-Gel Science and Technology》2021,99(2):430-443
Journal of Sol-Gel Science and Technology - A drug delivery system with near-infrared emissions response to drug delivery and release is essential as marking or targeting drug delivery system. For... 相似文献
82.
83.
惯性约束聚变的设计要求在靶丸内形成均匀光滑的氘氚冰层, 靶丸周围的热环境对冰层的质量特别是低阶粗糙度有很大的影响. 本文对自主研发的黑腔冷冻靶实验装置中的热物理问题展开了数值模拟, 重点考察了黑腔冷冻靶的传热和流体力学特性. 通过参数分析得到了自然对流对靶丸温度均匀性产生影响的临界条件. 比较了黑腔不同布置朝向时的流场和温度分布, 结果显示黑腔水平布置时自然对流更加强烈, 造成的靶丸温度不均匀性也更大. 在此基础上, 讨论了消除自然对流影响的可能性, 结果发现仅当黑腔垂直布置时利用黑腔分区方法能够消除对流效应对靶丸温度不均匀性的影响而黑腔水平布置时不能消除. 研究结论对于实验中冷冻靶结构的设计、改进和实验的开展等具有指导意义. 相似文献
84.
Theoretical studies of cobalt(I)‐catalyzed hydroacylation of vinylsilanes and alkyl aldehydes 下载免费PDF全文
Density functional theory (DFT) was used to investigate computationally cobalt(I)‐catalyzed hydroacylation of vinylsilanes and alkyl aldehydes to give ketones. Calculation indicated that cobalt(I)‐catalyzed hydroacylation had eight possible reaction pathways. In the cobalt‐hydride complexes IM2a and IM2b, the hydrogen migration occurred prior to the carbon–carbon bond‐forming reaction. In the complexes IM3a1 and IM3b1, the carbonyl elimination reaction occurred prior to the direct reductive elimination reaction. In the cobalt–carbonyl complexes IM4a and IM4b, the carbonyl insertion reaction was much easier to achieve than the decarbonylation reaction. The dominant reaction pathway was the reaction channel IM1a → TS1a → IM2a → TS2a1 → IM3a1 → TS4a → IM4a → TS5a → IM5a → TS6a → IM6a, and the reductive elimination reaction was the rate‐determining step for this channel, so the dominant product predicted theoretically was the linear ketone. Furthermore, the solvation effect was remarkable, and it decreased generally the free energies of the species. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
85.
Haibao?Shao Chunlei?WangEmail author Shuhong?Xu Zhuyuan?Wang Haihong?Yin Yiping?CuiEmail author 《Journal of fluorescence》2015,25(2):305-310
Controllable doping is an effective way of tuning the properties of semiconductor nanocrystals (NCs). In this work, a simple strategy of fast doping Cu ions into ZnSe NCs under ambient conditions was proposed. The principle of doping is based on hydrazine (N2H4) promoted cation exchange reaction. By direct addition of Cu ion stock solution into the preformed ZnSe NCs, Cu doped ZnSe NCs can be obtained. Furthermore, the emission of doped NCs can be tuned by changing the amount of impurity ion addition. The cation exchange reaction is facilitated by three factors: 1) N2H4 addition, 2) fast impurity ions, and 3) partial stabilizer removal. The proposed cation exchange reaction in aqueous solution could be an alternate route for NC doping as well as synthesis of ionic NCs. 相似文献
86.
Pulsed microwave-driven argon plasma jet with distinctive plume patterns resonantly excited by surface plasmon polaritons 下载免费PDF全文
Atmospheric lower-power pulsed microwave argon cold plasma jets are obtained by using coaxial transmission line resonators in ambient air.The plasma jet plumes are generated at the end of a metal wire placed in the middle of the dielectric tubes.The electromagnetic model analyses and simulation results suggest that the discharges are excited resonantly by the enhanced electric field of surface plasmon polaritons.Moreover,for conquering the defect of atmospheric argon filamentation discharges excited by 2.45-GHz of continued microwave,the distinctive patterns of the plasma jet plumes can be maintained by applying different gas flow rates of argon gas,frequencies of pulsed modulator,duty cycles of pulsed microwave,peak values of input microwave power,and even by using different materials of dielectric tubes.In addition,the emission spectrum,the plume temperature,and other plasma parameters are measured,which shows that the proposed pulsed microwave plasma jets can be adjusted for plasma biomedical applications. 相似文献
87.
Skeleton Decoration of NHCs by Amino Groups and its Sequential Booster Effect on the Palladium‐Catalyzed Buchwald–Hartwig Amination 下载免费PDF全文
Yin Zhang Dr. Vincent César Golo Storch Dr. Noël Lugan Dr. Guy Lavigne 《Angewandte Chemie (International ed. in English)》2014,53(25):6482-6486
A challenging synthetic modification of PEPPSI‐type palladium pre‐catalysts consisting of a stepwise incorporation of one and two amino groups onto the NHC skeleton was seen to exert a sequential enhancement of the electronic donor properties. This appears to be positively correlated with the catalytic performances of the corresponding complexes in the Buchwald–Hartwig amination. This is illustrated, for example, by the quantitative amination of 4‐chloroanisole by morpholine within 2 h at 25 °C with a 2 mol % catalyst/substrate ratio or by a significant reduction of catalytic loading (down to 0.005 mol %) for the coupling of aryl chlorides with anilines (max TON: 19 600). 相似文献
88.
1,3-benzodioxole-5-yl-methyl-maleimide (BDOMM), a type of hydrogen-abstraction photoinitiator with both hydrogen donor and acceptor in one molecule for free radical photopolymerization, was synthesized through the reaction of piperonyl amine and maleic anhydride and characterized by IR, UV and 1H NMR spectroscopy. The results obtained indicated that the introduction of BDOMM could avoid the use of additional amine coinitiator, decrease the leachablity of photoinitiator and maintain high photo-initiation efficiency. 相似文献
89.
A novel three‐component strategy for the azidotrifluoromethylation of alkenes has been presented here. The reaction proceeded smoothly under gentle temperature and gave the bifunctional olefins in high yields. Furthermore, 1,3‐dipolar reactions between azide‐containing products and phenylacetylene revealed great potential in molecular modification by using this method. 相似文献
90.
Some novel cycloaddition reactions based on benzyne and olefins have been developed.These reactions were performed in the absence of a transition metal catalyst,and they displayed good yields.These cycloaddition reactions of benzyne with olefins provide effective routes for synthesizing benzocyclobutenes,biaryl compounds and 9,10-dihydrophenanthrene derivatives. 相似文献