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991.
992.
Graft copolymerization of acrylic acid (AA) onto polyphenylene sulfide (PPS) nonwoven initiated by low temperature plasma was studied. The effects of various conditions on graft reaction and the grafting rate were investigated. SEM images showed that PPS nonwoven was grafted, and the graft copolymerization only occurred on the surface of PPS. It may be due to the chain transference going with the graft copolymerization. It was found that with the increasing of plasma power, treatment time, space between electrodes, monomer concentration, and temperature of graft polymerization, the grafting rate increased at first, went to the top, and then decreased. The PPS nonwoven surface graft reaction could be optimized by the following processing conditions: 120 s of plasma treatment time, 50 W of plasma power, 1.5 cm of space between electrodes, 30% (w/w) of monomer concentration, and 50°C of temperature of graft polymerization. Measurement of XPS showed that the peak of C1s of graft polyacrylic acid was existed, and the peak area increased with the increase of the grafting rate. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 5884–5889, 2006 相似文献
993.
In this paper, we first uncover a fact that a partial adiabatic quantum search with \(O(\sqrt{N/M})\) time complexity is in fact optimal, in which \(N\) is the total number of elements in an unstructured database, and \(M\) ( \(M\ge 1\) ) of them are the marked ones(one) \((N\gg M)\) . We then discuss how to implement a partial adiabatic search algorithm on the quantum circuit model. From the implementing procedure on the circuit model, we can find out that the approximating steps needed are always in the same order of the time complexity of the adiabatic algorithm. 相似文献
994.
Zhengtao Ding 《Asian journal of control》2014,16(2):335-344
This paper deals with observer designs for a proposed mathematical model of circadian rhythms which exist in almost every living organism. A 7th order model for mammalian circadian rhythms which captures the main dynamic features is considered in this paper. A recent result of one‐sided Lipschitz observer design in the literature is applied to this mammalian model to show a possibility of reducing measurements for circadian models in system biology. The mammalian model presented may contain an uncertainty parameter. An adaptive design of the Lipschitz observer is then applied to deal with this case. Besides detailed designs of both observers, detailed analysis is also performed for nonlinear functions in the mammalian model to show that the Lipschitz observers can indeed be applied. Several simulation studies of the proposed observers are carried out with the results shown in this paper. 相似文献
995.
In this paper, we present a QKA protocol with the block transmission of EPR pairs. There are several advantages in this protocol. First, this protocol can guarantee both the fairness and security of the shared key. Second, this protocol has a high qubit efficiency since there is no need to consume any quantum state except the ones used for establishing the shared key and detecting eavesdropping. In addition, this protocol uses EPR pairs as the quantum information carriers and further utilizes single-particle measurements as the main operations. Therefore, it is more feasible than the protocols that need to perform Bell measurements. Especially, we also introduce a method for sharing EPR pairs between two participants over collective-dephasing channel and collective-rotation channel, respectively. This method is meaningful since sharing EPR pairs between two participants is an important work in many quantum cryptographic protocols, especially in the protocols over non-ideal channels. By utilizing this method, the QKA protocols, which are based on EPR pairs, can be immune to these kinds of collective noise. 相似文献
996.
997.
Nanoscale colloidal silica showed high reactivity toward curing epoxy resins to form epoxy–silica nanocomposites under mild conditions. Adding a certain amount (5000 ppm) of magnesium chloride lowered the activation energy of the reaction from 71 to 46 kJ/mol. Less and more magnesium chloride both exhibited counter action on lowering the activation energy of the curing reaction. Tin chloride dihydrate and zinc acetylacetonate hydrate were also added into the curing compositions, however, showing no significant effect on promoting the curing reaction. Through this curing reaction, epoxy–silica nanocomposites containing high silica contents up to 70 wt % were obtained. Therefore, this reaction provided a novel and convenient route in preparation of epoxy–silica nanocomposites. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 95: 1237–1245, 2005 相似文献
998.
点击劫持通过欺骗用户点击经过伪装的界面元素达到攻击目的。移动互联网环境下,智能手机的屏幕特征、手势识别、HTML5支持度高等特性成为点击劫持新的利用点。深入分析并实验验证智能手机脆弱特性,在此基础上提出点击劫持在智能手机上的潜在攻击方案。进而设计并实现一套有针对性的检测方案。该方案从静态页面和动态行为两个角度提取攻击特征,并进行基于规则的量化评估与组合判定。实验结果表明该方案可以有效地降低传统页面特征检测方案的漏报和误报情况。 相似文献
999.
针对合同网协议协商机制缺乏问题求解质量与效率分析的情况,设定假设条件,构建马尔可夫链模型,得出了利用目前已有的合同类型无法保证全局收敛的结论.在此基础上,提出了变邻域合同系的概念,通过分析控制方式对收敛性的影响,得出了集中式控制可以保证全局收敛以及分布式控制以概率保证全局收敛的结论,并设计了概率的计算方法.采用Doebin理论,对应用变邻域合同系的收敛速率进行分析,得出了集中式控制收敛速率与分布式控制收敛速率的上下界估计. 相似文献
1000.