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451.
Yuan-Yuan Quan Duo Wang Qing-Qing He Ji-Wen Hu Mei Tian Xin-Jiao Wang 《Liquid crystals》2020,47(5):737-749
ABSTRACTThis paper designed and synthesised a series of V-shaped liquid crystal molecules (X-SBAnE) with resorcinol as the core and Schiff base as the mesogenic arms (X-SBAAn). The effects of polarity of terminal groups (X=-CH3O,-CH3,-Cl) and length of flexible chain (n = 4,6,8) on mesogenic ranges were discussed. The chemical structure of X-SBAAn and X-SBAnE was studied using FT-IR and 1H-NMR while their thermal behaviour and mesogenic ranges were investigated via differential scanning calorimetry (DSC) and polarising optical microscopy (POM). The results indicated that X-SBAAn containing OCH3 and Cl substituents exhibited mesophase except for the analogue having CH3 substituent which was found to be non-mesogenic. All of the synthesised X-SBAnE had liquid crystal properties and exhibited nematic phases in heating and cooling. The length of the flexible spacers and terminal groups significantly influenced their mesogenic ranges. 相似文献
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454.
Xunbo Yu Xinzhu Sang Duo Chen Peng Wang Xin Gao Tianqi Zhao Binbin Yan Chongxiu Yu Daxiong Xu Wenhua Dou 《中国光学快报(英文版)》2014,12(6):60008-33
An auto-stereoscopic three-dimensional (3D) display method with the narrow structure pitch and high dense viewpoints is presented. Normally, the number of views is proportional to the structure pitch of the lenticular lens array. Increasing the density of views will decrease the spatial display resolution. Here a lenticular lens array with one pitch covering 5.333 subpiexels and a novel subpixel arrangement method are designed, and a 32 view 3D display is demonstrated. Compared with the traditional 6-view 3D display, the angular resolution and the displayed depth of field are significantly improved. 相似文献
455.
Changyuan Hu Rongfa Zhang Junhuai Xiang Tingzhi Liu Wenkui Li Mingsheng Li Shuwang Duo Fei Wei 《Journal of solid state chemistry》2011,184(5):1286-1292
A simple method is described for the synthesis of carbon nanotube/anatase titania composites by a combination of a sol-gel method with a self-assembly technique at 65 °C. This method makes use of polyelectrolyte for wrapping multi-walled carbon nanotube (MWCNT) and providing them with adsorption sites for electrostatically driven TiO2 nanoparticle deposition. The composites were characterized using X-ray diffraction, transmission electron microscopy, Fourier transform infrared and X-ray photoelectron spectroscopy, and photoluminescence for analyzing their crystal phase, microstructure, particle size, and other physicochemical properties. The results showed that MWCNT were covered with an anatase TiO2 thin layer or surrounded by an anatase TiO2 thick coating, which is constructed of TiO2 particles about 6 nm in size. The composites were rich in surface hydroxyl groups. The excited e− in conduction band of TiO2 may migrate to MWCNT. Concerning the potential applicability, MWCNT/TiO2 composites showed excellent photocatalytic activity toward the photodegradation of methyl orange. 相似文献
456.
Isotopic production cross sections of fragmentation residues produced by 18O ions on a carbon target near 260 MeV/nucleon 下载免费PDF全文
Xiao-Dong Xu Ya-Zhou Sun Shi-Tao Wang Bo Mei Shu-Ya Jin Xue-Heng Zhang Zhi-Yu Sun Yi-Xuan Zhao Shu-Wen Tang Yu-Hong Yu Duo Yan Fang Fang Yong-Jie Zhang Shao-Bo Ma 《中国物理C(英文版)》2022,46(11):111001-111001-6
The isotopic cross sections of residual nuclei produced in fragmentation reactions of 18O projectiles impinging on a carbon target at energies near 260 MeV/nucleon were measured at the HIRFL facility in Lanzhou (China). A full identification of atomic and mass numbers of fragments was achieved from the determination of their magnetic rigidity, energy loss, and time of flight. The production cross sections for a dozen of nitrogen, carbon, and boron isotopes were determined with uncertainties below 30% for most of the cases. The obtained cross sections for N and B isotopes show a rather good agreement with previous experimental data obtained with different projectile energies. The cross sections for some C isotopes seem to exhibit a dependence on the projectile energy. A comparison of the data and several theoretical model calculations are presented. 相似文献
457.
氧气放电等离子体温度测量研究 总被引:1,自引:0,他引:1
为了考察电激励氧碘激光器中放电腔内的宏观气体温度,由两片蚌形铜电极和一根长30 cm内径1.65 cm的耐热玻璃管构成放电腔装置,用一台最高功率500 W,频率13.56 MHz的射频装置对压力1 330Pa的纯氧气体进行了介质阻挡放电研究。利用O2(b,ν=0)的P支发射光谱,分别采用波尔兹曼直线作图法和计算机模拟发射光谱法,测量了氧气射频放电等离子体的宏观气体温度。对于低分辨率光谱,利用高斯拟合进行了分峰处理,利用峰面积表征发光强度,通过波尔兹曼作图法得到了宏观气体温度。利用氦氖激光器测得的光谱仪狭缝函数获得了计算1机模拟发射光谱,以最小二乘法作为判据,通过比较计算机模拟发射光谱和实测光谱获得了宏观气体温度。 相似文献
458.
Xiaorong Fu Zhitang Song Guangming Wu Jipo Huang Xinzhong Duo Chenglu Lin 《Journal of Sol-Gel Science and Technology》1999,16(3):277-281
MgO thin films have been prepared on Si substrates by a novel and simple sol-gel method using magnesium nitrate and collodion as starting material. Solutions consisting of magnesium nitrate in a mixture of collodion and ethanol were spin-coated onto silicon substrates. It was found that collodion was a necessary component to form stable sols and the crystallization and structures were clearly dependent on the amount of the collodion and the annealing temperature. The MgO thin films with good crystallization were obtained after annealing at 800°C. Meanwhile, the microstructure of the MgO films was examined by transmission electron microscopy and atomic force microscopy. 相似文献
459.
Chunhua Ren Huaimin Wang Duo Mao Xiaoli Zhang Qianqi Fengzhao Yang Shi Dr. Dan Ding Prof. Deling Kong Dr. Ling Wang Prof. Zhimou Yang 《Angewandte Chemie (International ed. in English)》2015,54(16):4823-4827
We demonstrate that the incorporation of one or two amino acids of phenylalanine (F) or 4‐fluoro phenylalanine (fF) will greatly lower the background fluorescence intensities of conventional quenched probes with quenchers. This enhanced quenching effect was due to the synergetic effect of the aggregation caused quenching and the presence of a quencher. Such strategy will not greatly affect the enzyme recognition properties to the probes. We also demonstrated that our self‐assembled nanoprobe with the enhanced quenching effect showed a better performance in cells for the detection of cell apoptosis than the unassembled probes. Our study demonstrates that using molecular self‐assembly can optimize and improve the performance of molecular probes and it provides a simple but very useful strategy to boost the signal‐to‐noise ratios of fluorescence probes. 相似文献
460.