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971.
In order to lower the operating voltage of blue-phase liquid crystal display (BPLCD), a BPLCD with insulating protrusion, which is sandwiched between dual-layer electrodes, is proposed. There are four electrodes in this structure; thus, we investigate different driving methods to find a proper driving method. The effect of protrusion’s dielectric constant on operating voltage of the proposed BPLCD is explored under various electrodes’ parameters. As a result, the operating voltage of the proposed BPLCD with protrusion’s dielectric constant of 1,000 is 9.8 V, which is reduced by ~ 4.67× compared with that of conventional in-plane switching (IPS) BPLCD (45.8 V). Moreover, the zigzag electrode structure is adopted to reduce the large off-axis image distortion index. Besides, the azimuth distortion index is defined to describe the gamma shift between the minimum and maximum gamma shift curves at a certain polar angle. The results show that the off-axis image distortion index can be reduced to 0.0834, the azimuth distortion index is 0.0810 and the viewing cone of contrast ratio larger than 1,000:1 is over 50ºas the zigzag proposed BPLCD is used. 相似文献
972.
In this note, a new characterization of an attained boundary point of the numerical range of an operator on a Hilbert space is given. As an application, we point out a gap in the proof of the main result in the paper [M.T. Chien, L. Yeh, On the boundary of the numerical range of a matrix, Appl. Math. Lett. 23 (2010) 725–727]. 相似文献
973.
Zengjie Fan Dr. Bing Ding Hongshuai Guo Minyuan Shi Yadi Zhang Shengyang Dong Dr. Tengfei Zhang Prof. Dr. Hui Dou Prof. Dr. Xiaogang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(45):10710-10717
Lithium–sulfur (Li–S) batteries are considered to be one of the most promising energy storage systems owing to their high energy density and low cost. However, their wide application is still limited by the rapid capacity fading. Herein, polydopamine (PDA)-coated N-doped hierarchical porous carbon spheres (NPC@PDA) are reported as sulfur hosts for high-performance Li-S batteries. The NPC core with abundant and interconnected pores provides fast electron/ion transport pathways and strong trapping ability towards lithium polysulfide intermediates. The PDA shell could further suppress the loss of lithium polysulfide intermediates through polar–polar interactions. Benefiting from the dual function design, the NPC/S@PDA composite cathode exhibits an initial capacity of 1331 mAh g−1 and remains at 720 mAh g−1 after 200 cycles at 0.5 C. At the pouch cell level with a high sulfur mass loading, the NPC/S@PDA composite cathode still exhibits a high capacity of 1062 mAh g−1 at a current density of 0.4 mA cm−2. 相似文献
974.
975.
A Multi‐responsive Regenerable Europium–Organic Framework Luminescent Sensor for Fe3+, CrVI Anions,and Picric Acid
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Dr. Wei Liu Xin Huang Dr. Cong Xu Dr. Chunyang Chen Prof. Lizi Yang Prof. Wei Dou Dr. Wanmin Chen Dr. Huan Yang Prof. Weisheng Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18769-18776
A novel luminescent microporous lanthanide metal–organic framework (Ln‐MOF) based on a urea‐containing ligand has been successfully assembled. Structural analysis revealed that the framework features two types of 1D channels, with urea N?H bonds projecting into the pores. Luminescence studies have revealed that the Ln‐MOF exhibits high sensitivity, good selectivity, and a fast luminescence quenching response towards Fe3+, CrVI anions, and picric acid. In particular, in the detection of Cr2O72? and picric acid, the Ln‐MOF can be simply and quickly regenerated, thus exhibiting excellent recyclability. To the best of our knowledge, this is the first example of a multi‐responsive luminescent Ln‐MOF sensor for Fe3+, CrVI anions, and picric acid based on a urea derivative. This Ln‐MOF may potentially be used as a multi‐responsive regenerable luminescent sensor for the quantitative detection of toxic and harmful substances. 相似文献
976.
977.
DNA在氨基功能化偶氮苯自组装膜表面的固定 总被引:1,自引:0,他引:1
采用简单快速的方法制备出将DNA固定在其表面的单分子层敏感膜.首先采用表面自组装技术将硅氧烷基偶氮苯衍生物H2NAzoCONHC3Si(OCH3)3(APDA-N-TMSPBA)组装在硅表面,在详细考察单分子层薄膜的化学结构、表面浸润性和分子表面形貌之后,又通过紫外吸收光谱(UV)在位考察了硅氧烷基偶氮苯衍生物的光学异构特性.在DNA在自组装薄膜固定后,X光电子能谱仪(XPS)结果显示出现了明显的磷元素信号,表明DNA分子可以成功固定在自组装膜表面. 相似文献
978.
导电聚合物由于其优越的稳定性和电化学性质,一直是蛋白质芯片敏感膜的研究热点.采用化学氧化聚合法分别制备出氨基和羧基功能化导电聚吡咯共聚物薄膜,通过调节体系单体比例(体积比)来改变导电共聚物的化学结构.采用傅里叶变换红外光谱表征了共聚物的化学组成,利用电化学循环伏安法考察共聚物薄膜的电化学活性变化.在此基础上,采用表面等离子谐振生化分析仪原位考察了牛血清白蛋白(BSA)在共聚物薄膜上的吸附动力学过程.由于共聚物薄膜上的功能基团的种类和含量不同,导致BSA吸附动力学和吸附量的差异.可以明显看出,蛋白质更容易在具有高的氨基密度或低的羧基密度的导电聚吡咯薄膜上进行吸附,随着氨基基团含量的增加,BSA在聚合物薄膜上的吸附量增大.相反,随着羧基基团含量的增大,BSA在共聚物薄膜上的吸附量减小.通过上述方法,可以控制蛋白质在导电聚合物上的吸附行为,进而为构建出更为敏感的、可精确控制的蛋白质芯片奠定基础. 相似文献
979.
Xuebin Zhu Yuping Sun Xuan Luo Hechang Lei Bosen Wang Wenhai Song Zhaorong Yang Jianming Dai Dongqi Shi Shixue Dou 《Journal of magnetism and magnetic materials》2010,322(2):242-246
Critical behavior of Ti-doped La0.7Ca0.3MnO3 ceramics are studied using magnetization methods. The results show that the paramagnetic–ferromagnetic transition is first order for the undoped sample, then for low-doping samples the mean-field model is suitable, and finally a 3D Heisenberg model is satisfied for higher doping samples. These findings demonstrate that the critical behavior of the magnetic transition for manganites is sensitive to Mn-site doping. 相似文献
980.
CeO2 buffer layers were deposited on YSZ single-crystal substrates using an RF-sputtering method. The development of crystalline textures of sputtered CeO2 films at different sputtering pressure and their effects on YBCO films, deposited by Metal Organic Deposition (MOD), were investigated. Both CeO2 and subsequent YBCO films grew well epitaxially. The relative XRD peak intensities of CeO2 (2 0 0) to substrate YSZ (2 0 0) increased with deposition pressure in the range of 3–5 mTorr and were inversely proportional to the θ–2θ scan FWHM values of CeO2 (2 0 0). Also, the reaction layers of BaCeO3 were thicker in the samples with lower CeO2 (2 0 0) intensities and poor out-of-plane alignment when CeO2 were deposited at the lower pressure of 3.3 mTorr. It is noted, however, that the superconducting layer grew well epitaxially on these BaCeO3 layers, possibly due to the epitaxial relation between CeO2 and YBCO. The superconducting critical currents of MOD-YBCO films showed an increasing tendency as both the Δ2θ (CeO2) and BaCeO3 peak intensities decreased. 相似文献