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111.
Changwen Ye Xiangjun Pei J. C. Liu 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2016,90(12):2397-2401
Densities and viscosities have been measured for the n-octanol + aviation kerosene (AK) + phosphoric acid (H3PO4) system with the mass fraction of H3PO4 in the range from w = 0 to 0.26 and in the temperature of 293.15–333.15 K. According to the experimental data, the measured viscosities were found well correlated with the temperature and mass fraction of H3PO4, which were fitted to regression equations. The result shows that the dilution effect of AK is obvious under the same temperature and mass fraction of H3PO4. 相似文献
112.
We propose a voltage-tunable hyperbolic dispersion metamaterial (HDM) consisting of silver nanowires and nematic liquid crystals (NLCs). The metamaterial shows a novel electro-optic effect, in which the dispersion relation switches between elliptic and hyperbolic dispersions at the visible waveband with an external electric field. HDM functionality is analysed in detail based on the effective medium theory. 5CB NLC is chosen for the simulation, and tunability is achieved between 454 and 475 nm. The effects of filling ratio on tunability are also analysed. Tunable bandwidth widens from 21 to 45 nm with decreased filling ratio from 0.27 to 0.09. Finally, the effects of birefringence (Δn) are considered. Tunable bandwidth widens from 21 to 63 nm as Δn changes from 0.2 to 0.6. These novel tunable performances of the HDM can be applied to optical devices and optical systems. 相似文献
113.
Changwen Ye Lin Lu Xiangjun Pei Yan Hu Jian Chen Yuanhao Wang 《Polymer Science Series B》2016,58(5):601-609
Thermal-insulating coating can lower the energy consumption and cooling costs, which caters to the tendency of environmental protection and energy conservation. Transparent waterborne polyurethane acrylate thin-film nanocomposite was developed by incorporating the fullerenol C60(OH)12(ONa)2 into the system using ultrasonic dispersion. The thin-film nanocomposite was then synthesized by ultraviolet radiation curing and chemical crosslinking, and its morphology and chemical structures were characterized. Thermogravimetric analysis and differential thermal gravity were used to evaluate the thermal stability. The surface and mechanical properties were tested by the pendulum hardness and MEK resistance. The optical and thermal-insulating properties were assessed by the ultravioletvisible-near infrared spectrophotometer and indoor environmental simulation experiment. The thermal-insulating measurements showed that the glass coated thin-film nanocomposite possessed better thermal-insulation effect than empty glass. 相似文献
114.
Yanyan Yuan Karine Le Guen Jingtao Zhu Zhanshan Wang Wenbin Li Mingwu Wen Christian Mény Haisheng Yu Yuying Huang Xiangjun Wei Philippe Jonnard 《Surface and interface analysis : SIA》2017,49(3):205-209
X‐ray absorption spectroscopy at the Co K edge was applied to investigate the chemical environment of Co atoms inside Co/Mo2C periodic multilayers. The results show a mixing between Co and Mo2C layers prior to any annealing process, whereas following annealing from 300 °C pure Co layers are observed. X‐ray absorption spectroscopy results are in agreement with previous nuclear magnetic resonance spectroscopy results. They indicate that the pure Co content increases upon annealing, while it is absent in the as‐deposited samples. The comparison of the results, based on the analysis of the data obtained on the multilayer samples and some reference materials, reveals that the ordering of Co atoms inside the Co layers increases upon annealing. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
115.
Determination of lansoprazole enantiomers in dog plasma by column‐switching liquid chromatography with tandem mass spectrometry and its application to a preclinical pharmacokinetic study
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Hao Wang Yantong Sun Xiangjun Meng Bo Yang Jian Wang Jingkai Gu 《Journal of separation science》2015,38(17):2960-2967
Lansoprazole, a selective proton pump inhibitor, has a chiral benzimidazole sulfoxide structure and is used for the treatment of gastric acid hypersecretory related diseases. To investigate its stereoselective pharmacokinetics, a column‐switching liquid chromatography with tandem mass spectrometry method was developed for the determination of lansoprazole enantiomers in dog plasma using (+)‐pantoprazole as an internal standard. After a simple protein precipitation procedure with acetonitrile, matrix components left behind after sample preparation were further eliminated from the sample by reversed‐phase chromatography on a C18 column. The fluent was fed to a chiral column for the separation of lansoprazole enantiomers. Baseline separation of lansoprazole enantiomers was achieved on a Chiralcel OZ‐RH column using acetonitrile/0.1% formic acid in water (35:65, v/v) as the mobile phase at 40°C. The linearity of the calibration curves ranged from 3 to 800 ng/mL for each enantiomer. Intra‐ and inter‐day precisions ranged from 2.1 to 7.3% with an accuracy of ±1.7% for (+)‐lansoprazole, and from 1.6 to 6.9% with an accuracy of ±3.5% for (–)‐lansoprazole, respectively. The validated method was successfully applied for the stereoselective pharmacokinetic study of lansoprazole in beagle dog after intravenous infusion. 相似文献
116.
Dr. Leilei Shi Dr. Wenbo Wu Yukun Duan Dr. Li Xu Dr. Yingying Xu Dr. Lidan Hou Prof. Xiangjun Meng Prof. Xinyuan Zhu Prof. Bin Liu 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(43):19330-19336
Developing non-cationic gene carriers and achieving efficient endo/lysosome escape of functional nucleic acids in cytosol are two major challenges faced by the field of gene delivery. Herein, we demonstrate the concept of self-escape spherical nucleic acid (SNA) to achieve light controlled non-cationic gene delivery with sufficient endo/lysosome escape capacity. In this system, Bcl-2 antisense oligonucleotides (OSAs) were conjugated onto the surface of aggregation-induced emission (AIE) photosensitizer (PS) nanoparticles to form core–shell SNA. Once the SNAs were taken up by tumor cells, and upon light irradiation, the accumulative 1O2 produced by the AIE PSs ruptured the lysosome structure to promote OSA escape. Prominent in vitro and in vivo results revealed that the AIE-based core–shell SNA could downregulate the anti-apoptosis protein (Bcl-2) and induce tumor cell apoptosis without any transfection reagent. 相似文献
117.
本文通过对载流导体附近运动电荷受力的再讨论,直观地展现了电场与磁场的相对性与整体性. 相似文献
118.
本文重点研究螺型住错偶极子和圆形夹杂界面刚性线的弹性干涉效应。利用复变函数方法,得到了该问题的一般解;此外还求出了只含一条界面刚性线时的封闭解答,得到了刚性线尖端的应力强度因子以及作用在螺型位错偶板子中心的像力和像力偶矩。研究结果表明:位错偶板子对应力强度因子具有很强的屏蔽或反屏蔽效应;软夹杂吸引位错偶极子,而刚性线排斥位错偶板子,在一定条件下,位错偶极子在刚性线附近出现一个平衡位置;当刚性线的长度争材料剪切模量比达到临界值时,可以改变偶极子和界面之间的干涉机理;刚性线长度对位错偶极子中心像力偶矩也有很大的影响。 相似文献
119.
根据瑞利-索末菲标量衍射理论分析了相位连续变化型波带片对高斯光束的衍射特性。在高斯光束入射下,对相位连续变化型波带片光轴和焦平面上的太赫兹强度分布特性进行了模拟,分析了入射光束的束腰半径和束腰位置对衍射场的影响,并与平面波入射的情况进行了对比。数值结果显示,相位连续变化型波带片可以实现对高斯分布太赫兹波的聚焦。相位连续变化型波带片的衍射规律与薄透镜的聚焦规律相似。通过合理调整束腰与波带片之间的距离可以保证衍射效率在85%以上。与平面波相比,高斯光束入射下的焦点处中心场强较小,但衍射效率较高。 相似文献
120.
Cluster synchronization in the adaptive complex dynamical networks via a novel approach 总被引:2,自引:0,他引:2
This Letter investigates cluster synchronization in the adaptive complex dynamical networks with nonidentical nodes by a local control method and a novel adaptive strategy for the coupling strengths of the networks. In this approach, the coupling strength of each node adjusts adaptively only based on the state information of its neighborhood. By means of the proposed scheme, the sufficient conditions for achieving cluster synchronization are derived analytically by utilizing Lyapunov stability theory. It is demonstrated that the synchronization performance is sensitively affected by the control gain, the inner-coupling matrix and the network topological structure. The numerical simulations are performed to verify the effectiveness of the theoretical results. 相似文献