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131.
We investigate the Lipschitz structure of ℓp and Lp for 0<p<1 as quasi-Banach spaces and as metric spaces (with the metric induced by the p-norm) and show that they are not Lipschitz isomorphic. We prove that the PT29C7-1-B/0?wchp=dGLbVlb-zSkWz" alt="View the MathML source" title="View the MathML source" align="absbottom" border="0" height=11 width="10"/>-space L0 is not uniformly homeomorphic to any other Lp space, that the Lp spaces for 0<p<1 embed isometrically into one another, and reduce the problem of the uniform equivalence amongst Lp spaces to their Lipschitz equivalence as metric spaces. 相似文献
132.
Junyou Shi Ping Li Yuxiang Bu Weihua Wang Zhaoxia Mou Rui Song 《International journal of quantum chemistry》2008,108(7):1246-1256
The effects of amino acid residues in the presence or absence of water molecules on the isomerization of the singlet state of HNO/HON have been systematically investigated at the B3LYP/6‐311++G** level of theory. The structural characteristics, proton transfer (PT) mechanisms, and the corresponding thermodynamic and kinetic parameters, have been discussed, respectively. All the optimized complexes have been characterized by the ring structures through the intermolecular H‐bonds. The origin of the increase in N? H stretching frequency (blue shifts) occurring in the reactants has also been investigated using the natural bonding orbital (NBO) analyses, which is mainly attributed to the decrease of the electron densities in the antibonding orbital of the N? H bonds as well as the increase of the polarization of the N? H bond. All the PTs proceed with the concerted mechanisms since no ionic intermediates have been located during PT processes. At the same time, the cooperative effects of amino acid residues and water molecules on the selected PT processes have been observed, where the PTs assisted solely by the selected residues cannot occur without the participation of the water molecule. Overall, the introductions of one or two water molecules are more favorable for the isomerization of HNO assisted by the amino acid residues. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 相似文献
133.
戴寿超 《湖南理工学院学报:自然科学版》2014,(4):63-67
简要介绍了火电厂系统主接线和发变组主要保护配置,针对某机组运行时显示的故障现象,分析发变组保护装置动作报告和机组故障录波的特征,通过排查判断是发电机出口PT接地故障,对故障原因进行分析查找,并制定出相应的处理和防范措施. 相似文献
134.
TAT-NEP1-40融合蛋白的表达、纯化及蛋白转导功能的鉴定 总被引:1,自引:0,他引:1
为大量获得高纯度具有蛋白转导功能并可以穿过血脑屏障的融合蛋白TAT—NEP1-40,将构建好的表达载体pTAT—NEP1—40转化大肠杆菌BL21(DE3)进行表达后。将融合蛋白进行纯化和复性,鉴定蛋白转导功能。带有重组质粒pTAT—NEP40的大肠杆菌经IPTG诱导后,主要以包涵体形式表达,融合蛋白的分子量大小为14kD,其表达量占菌体总蛋白量的31.59%,纯化后目的蛋白纯度达95.6%,通过免疫组化染色显示融合蛋白可以穿过血脑屏障进入脑组织。上述结果表明利用pTAT—NEP1-40重组质粒,可以成功地表达TAT—NEP1—40;纯化后该蛋白具有穿过血脑屏障的功能,为NEP1-40功能的进一步研究提供了基础。 相似文献
135.
方惠蓉 《长春师范学院学报》2014,(4):37-40
伴随电子科技的繁荣和人们对生活水平和质量要求的不断提高,无线遥控开关的设计也越来越先进化、高科技化。为了扩大无线遥控开关的适用范围,本文设计了一款结构简单、使用简易方便、空间体积小的基于PT2262/PT2272的四路无线遥控开关,简要分析了设计原由,电路设计主要包含发射部分和接收部分,并对整个电路进行了详细的描述。 相似文献
136.
Yan Tang Xiangbo Yang Jian Zheng Xiaopeng Tang Huizhou Wu Dongmei Deng Hongzhan Liu 《Annalen der Physik》2019,531(12)
Aperiodic 1D Thue–Morse (TM) multilayer optical structures composed of two parity‐time‐symmetric (PT‐symmetric) elements are constructed. The transfer matrix and scattering matrix are utilized for singular propagation characteristic analysis of the structures. The structures display interesting and singular properties, including an unusual eigenvalue spectra, transparency, and unidirectional reflectionless and unidirectional invisibility. Additionally, even‐generation and odd‐generation structures show a significant difference in the aforementioned four properties. The main reason for this is the symmetry difference between the two structures: for even‐generation structures, each individual element as well as the entire system with respect to the PT‐symmetry; while for the odd‐generation structures, each individual element has PT‐symmetry; however, the system as a whole does not have PT‐symmetry. The propagation characteristics of the entire structure, which is not a PT‐symmetric system being composed of PT‐symmetric elements, have not yet been reported. This work can contribute to the understanding of the TM sequence, as well as contribute to understanding the influence of the degree of PT‐symmetry on the singular optical propagation characteristics of aperiodic optical structures. Additionally, this may open new possibilities for important applications, such as the design of a diverse family of all‐optical devices with intriguing behaviors. 相似文献
137.
The influences of different transmission electron microscopy (TEM) specimen preparation techniques on the chemical composition of Pb(Mg1/3Nb2/3)O3–PbTiO3 (PMN–PT) single crystals was studied. Ion-milled samples where no cooling with liquid nitrogen (L-N2) was applied show permanently changed composition also deep inside the bulk material. When the PMN–PT samples were cooled to L-N2 temperature during the ion-milling process and in addition lower accelerating voltages were used, the chemical composition was altered only in the thinnest parts close to the specimen edge. Samples prepared using only tripod polishing technique show compositional irregularities close to the specimen edge. For the preparation of lead-containing samples, such as PMN–PT single crystals, a combination of tripod polishing and short Ar-ion-milling at low accelerating voltages while cooling the samples to liquid nitrogen temperature proved to be the most suitable to obtain artefact-free electron-transparent TEM lamellae. 相似文献
138.
利用射频磁控溅射技术在LaNiO3/SiO2/Si(100)基底上制备了厚 度约为250 nm的0.65PMN-0.35PT(PMN-PT)薄膜. 研究高压氧氛围退火方式对PMN-PT薄膜晶体结构、形貌以及电学性能的影响. 经过XRD测试发现,在高压氧气氛围中, 温度为400℃下退火后的PMN-PT薄膜具有纯的钙钛矿相结构, 具有完全的(100)择优取向, 且衍射峰尖锐, 表明经过高压退火后的薄膜结晶极为充分. SEM表面形貌测试结果显示, 经高压退火处理的PMN-PT薄膜表面呈现出棒状或泡状的形貌. 铁电性能测试表明: 氧气氛围压强4 MPa, 退火时间4h的PMN-PT薄膜样品具有较好的铁电性能, 其剩余极化强度Pr达到10.544 μC/cm2, 且电滞回线形状较好, 但漏电流较大, 这可能是由于其微结构所导致.同时介电测试发现: PMN-PT薄膜样品具有极好的介电性能, 其在1 kHz下测试的介电常数εr达到913, 介电损耗tgδ 较小, 仅为0.065.
关键词:
射频磁控溅射
高压退火
0.65PMN-0.35PT
介电 相似文献
139.
Shao-Ming Fei 《Czechoslovak Journal of Physics》2006,56(9):887-892
We study the quantum entanglement and separability of Hermitian and pseudo-Hermitian systems of identical bosonic or fermionic
particles with point interactions. The separability conditions are investigated in detail. 相似文献
140.
Wolfgang Kandler Rainer Schuhmacher Susanne Roch Patricia Schubert-Ullrich Rudolf Krska 《Accreditation and quality assurance》2004,9(1-2):82-89
After 7 years of successful operation, the database of the proficiency testing (PT) scheme for water analysis organized by the Institute for Agrobiotechnology (IFA), Tulln contains nearly 4,000 data sets from over 300 interlaboratory comparison samples. About 70 analytical parameters (major ions, metals, trace ions, herbicides, volatile halogenated hydrocarbons, organochlorine pesticides and polycyclic aromatic hydrocarbons) were covered by the PT scheme. The data were evaluated using robust statistics in order to determine a set of coefficients of variation (CV) for each analytical parameter. Concentration and time dependence of the CV were checked. The CV were combined to obtain standard deviations for proficiency assessment (Z-score criteria). Furthermore, a viewer program was designed to facilitate monitoring of the analytical performance of participating laboratories. 相似文献