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991.
This article reports on the experiments performed in the Sr–Ru–O system, the motivation behind them and their impact on basic research and device applications. It refers to the time from 1987 to 2003, with emphasis on the occurrences before the discovery of superconductivity in Sr2RuO4 in 1994. Apart from the title compound Sr2RuO4 itself and related ruthenates, it touches on many different topics like titanates, ferrates, high-Tc superconducting cuprates, crystal growth by floating zone melting and thin films as well as fundamental and applied research.  相似文献   
992.
侯磊  韩海年  张龙  张金伟  李德华  魏志义 《物理学报》2015,64(13):134205-134205
243 nm是氢原子1S-2S能级跃迁光谱波长. 本文利用Pound-Drever-Hall稳频技术将972 nm光栅反馈外腔半导体激光稳定在一个高精细度低膨胀系数的超稳法布里-珀罗腔上, 通过锥形放大器放大和腔内两次共振增强倍频得到243 nm激光, 最终实现用于探测氢原子1S-2S双光子跃迁的243 nm窄线宽激光.  相似文献   
993.
This paper deals with the conception, the synthesis by reactive extrusion and the characterization of new materials based on comb-like nanostructured copolymers. Among these structures, the initially studied polyamide-g-polyolefin (PA-g-PO) exhibits a unique balance of low modulus at room temperature and a high level of thermo-mechanical resistance. To generate these structures, two different synthesis processes - “grafting onto” and “grafting from” - have been compared to generate the expected grafted and nanostructured morphologies through different examples: polyamide-g-polyolefin (PA-g-PO), poly(oxyethylene glycol)-g-polyolefin (PEG-g-PO), polyamide-g-poly(methyl methacrylate) (PA-g-PMMA) and poly(methyl methacrylate)-g-polyolefin (PMMA-g-PO). It is concluded that the “grafting onto” method allows the expected morphologies to be generated more easily. Moreover, key parameters which control the morphology development have been identified from these studies. Finally, some potential industrial applications are proposed for these structures, linked with their key performances.  相似文献   
994.
In both the periodic and non-periodic case we construct non-analytic complex-valued solutions for the generalized KdV equation with appropriate analytic initial data. Moreover, for the KdV and mKdV we construct real-valued non-analytic solutions.  相似文献   
995.
给出一类新的R adon型不等式,它们在代数不等式研究中有着广泛的应用,利用它们可直接得到一大批新的分式型不等式,也可运用它们证明或推广许多不等式.  相似文献   
996.
The opinions of logistics educators in Taiwan on OR practices in the domestic logistics industry are explored in this research. In this study, questionnaires were given to 42 pre-screened educators at 10 logistics departments and graduate institutes. According to the 37 valid returned questionnaires, 70% of the responding educators believe the major source of OR techniques in Taiwan’s logistics industry originates from individual employee training, while 92% believe OR is not widely used primarily because companies are unfamiliar with OR techniques. OR techniques were considered helpful in solving problems by 73%. Generally speaking, familiarity with OR techniques is not associated with implementation of OR techniques by educators. Additionally, logistics educators express concern about insufficient training for logistics students in Taiwan. However, they are optimistic about the logistics industry’s willingness to more actively adopt OR techniques in Taiwan in the next two years.  相似文献   
997.
A new electrochromic polymer, poly(2,3,5,8‐tetra(thiophen‐2‐yl)quinoxaline) (PTTQ), was synthesized electrochemically and its electrochromic properties were investigated. The polymer was characterized by Cyclic Voltammetry, Fourier Transform infrared spectroscopy, UV‐Vis‐NIR Spectroscopy, and colorimetry. Spectroelectrochemistry analysis demonstrated that the polymer can undergo both p‐ and true n‐type doping processes. The polymer, (PTTQ), has three accessible color states: an oxidized transmissive, a neutral light bluish‐green, and a reduced transmissive light gray. Switching ability of the polymer was evaluated by kinetic studies. The polymer revealed an excellent optical contrast of 98% in the NIR region. Outstanding optical contrast in the NIR region, high stability and fast switching times make this polymer an excellent candidate for NIR device applications. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 3723–3731, 2008  相似文献   
998.
The mission of Stone Industry Development Center (SIDC) at Taiwan attempts to promote the upgrading of the Taiwanese stone industry which recently has suffered a severe depression. After several years of technical developments, SIDC tends to shift focus to efficient use of existing knowledge/information. Consequently, a knowledge portal system (KPS) is expected to be a strategic tool to improve the competitiveness of the Taiwanese stone industry. This study proposes a fuzzy AHP approach to help five domain experts individually evaluate three KPS development tools. Then, a technique to determine the weights of experts, which is used while aggregating group decisions, is addressed. Finally, the weighted geometric mean method is applied to reach the final decision.  相似文献   
999.
1000.
We propose a method for finding analytic center of a convex feasible region whose boundaries are defined by quadratic functions. The algorithm starts from an arbitrary initial point and approaches to the desired center by simultaneously reducing infeasibility or slackness of all constraints. A partial Newton step is taken at each iteration.Research supported in part by the ONR under grant N00014-87-K-0214 and by the NSF under grant CCR-8810107.Research supported in part by the NSF under grant ECS-8721709.  相似文献   
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