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排序方式: 共有3949条查询结果,搜索用时 15 毫秒
941.
Dr. Yun Qiao Dr. Keishiro Tahara Prof. Qian Zhang Prof. Xi‐Ming Song Prof. Jun‐ichi Kikuchi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1340-1348
Anionic cerasomes, which consist of a liposomal lipid bilayer and a ceramic surface, were used as a soft interface for the construction of an integrated modified electrode to achieve the transmission of chemical information from a redox enzyme through electrical signals. The morphological properties of the cerasomes were systematically compared with those of two structural analogues, namely, liposomes and silica nanoparticles. The results indicated that the cerasomes combined the advantages of liposomes and silica nanoparticles. The lipid bilayer gave excellent biocompatibility, as in the case of liposomes, and high structural stability, similar to that of silica nanoparticles, was derived from the silicate framework on the cerasome surface. The performance at the electrochemical interface created by means of a combination of cerasomes and horseradish peroxidase on a glassy carbon electrode was much better than those achieved with liposomes or silica nanoparticles instead of cerasomes. The potential use of cerasomes in the construction of supramolecular devices for mediator‐free biosensing was evaluated. 相似文献
942.
Wenyuan Fang Prof. Libin Liu Ting Li Zhao Dang Dr. Congde Qiao Dr. Jinku Xu Yanyan Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(3):878-883
Membranes with special functionalities, such as self‐cleaning, especially those for oil/water separation, have attracted much attention due to their wide applications. However, they are difficult to recycle and reuse after being damaged. Herein, we put forward a new N‐substituted polyurethane membrane concept with self‐healing ability to address this challenge. The membrane obtained by electrospinning has a self‐cleaning surface with an excellent self‐healing ability. Importantly, by tuning the membrane composition, the membrane exhibits different wettability for effective separation of oil/water mixtures and water‐in‐oil emulsions, whilst still displaying a self‐healing ability and durability against damage. To the best of our knowledge, this is the first report to demonstrate a self‐healing membrane for oil/water separation, which provides the fundamental research for the development of advanced oil/water separation materials. 相似文献
943.
944.
Xiaolin Wang Qiao Yang Yixue Cao Haibin Hao Junhan Zhou Prof. Dr. Jingcheng Hao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17857-17865
The gelation behavior of cationic surfactants with different counterions, Br?, [FeCl3Br]?, and [CeCl3Br]?, in imidazolium ionic liquids (ILs) and protic ethylammonium nitrate was investigated. Small‐angle X‐ray scattering measurements and freeze‐fracture transmission electron microscopy observations revealed the lamellar phases of metallosurfactant ionogels. The characteristics of imidazolium ILs, including the size and type, have effects on metallosurfactant ionogel properties, such as transformation temperatures, interlayer spacing, and mechanical strength. Cubic fluorite structured cerium oxide nanoparticles (CeO2 NPs) were produced by using metallosurfactant ionogels as precursors. Cubic fluorite CeO2 exhibited good catalase mimetic activity toward H2O2 to generate O2, providing more multiple mimetic enzyme activities of CeO2 NPs for H2O2. 相似文献
945.
具有中心频率的窄带随机振动是一种典型的环境振动,其振动特征与环境的变化密切相关.本文以双稳压电悬臂梁能量采集系统为研究对象,分析系统在不同磁铁间距下的等效线性固有频率特性,以带通滤波器输出一定带宽的窄带随机激励模拟环境振动,研究系统的响应和能量采集特征.研究表明,对于一定带宽的窄带随机激励,一方面系统始终存在一个固定的磁铁间距使其输出达到峰值,另一方面当激励中心频率在一定范围内变化时,系统还分别存在另外两个或一个不同磁铁间距也能使系统输出达到峰值,而且该峰值特性是系统在其等效线性固有频率处诱导双稳或单稳“共振”形成的.研究结果可为具有窄带随机激励特征的振动能量采集提供一定的理论和技术支持. 相似文献
946.
947.
提出了一种简单的高灵敏度的光纤高温探针传感器, 该传感器由一小段多模光纤和一端镀有银膜的单模光纤熔接而成. 由于单模光纤和多模光纤的纤芯直径不同, 当光波从多模光纤传输至多模光纤和单模光纤的熔接端面时, 一部分纤芯光耦合进包层, 因为单模光纤纤芯的折射率和包层的折射率不同, 不同模式的光经过银膜反射后在多模光纤内重新耦合进单模光纤, 最终形成干涉.随着外界温度的升高, 干涉谱峰值会向长波方向漂移. 实验结果证明这种传感器在470 ℃–600 ℃范围内具有很好的稳定性, 线性度达99.7%, 灵敏度为120 pm/℃, 可作为远距离反射型探针温度传感器, 在石油探测和油气田开发等领域有着广泛的应用前景.
关键词:
光纤传感
温度测量
Michelson干涉 相似文献
948.
本文通过理论和实验对液晶 5CB在剪切和电场耦合作用下流变行为进行了研究. 采用液晶连续理论, 建立了包括界面锚定能, 弹性自由能, 介电自由能和流动能在内的系统 Gibbs自由能公式, 通过最小化系统自由能的方法求解液晶在剪切和电场耦合作用下的取向分布及其黏度变化, 从分子基础模型上揭示了液晶在耦合作用下的流变行为、微观机理及其影响规律, 并通过流变测试对此进行验证. 对比分析了理论和试验结果的误差和原因, 发现界面锚定效应对于液晶分子的取向和黏度具有重要影响. 理论和试验结果均表明, 液晶在电场作用下具有明显的电黏效应, 表现出非牛顿流变行为, 其黏度值由剪切和电场的竞争和耦合作用共同决定. 在外电场作用下液晶的黏度可以增加到初始值的 4倍左右, 液晶这种其自身黏度可随着外场 (例如运动速度) 改变的特性在一定的条件下可以自适应地满足不同工况对黏度的要求, 这对实现智能摩擦润滑具有重要的意义.
关键词:
液晶
流变行为
电黏效应
耦合作用 相似文献
949.
950.
We review our recent work on the methodology development of the excited-state properties for the molecules in vacuum and liquid solution.The general algorithms of analytical energy derivatives for the specific properties such as the first and second geometrical derivatives and IR/Raman intensities are demonstrated in the framework of the time-dependent density functional theory(TDDFT).The performance of the analytical approaches on the calculation of excited-state energy Hessian has also been shown.It is found that the analytical approaches are superior to the finite-difference method on the computational accuracy and efficiency.The computational cost for a TDDFT excited-state Hessian calculation is only 2–3 times as that for the DFT ground-state Hessian calculation.With the low computational complexity of the developed analytical approaches,it becomes feasible to realize the large-scale numerical calculations on the excited-state vibrational frequencies,vibrational spectroscopies and the electronic-structure parameters which enter the spectrum calculations of electronic absorption and emission,and resonance Raman spectroscopies for medium-to large-sized systems. 相似文献