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991.
Florian D. Jochum F. Romina Forst Patrick Theato 《Macromolecular rapid communications》2010,31(16):1456-1461
A series of thermo‐responsive PNIPAM copolymers containing different amounts of fulgimide moieties has been synthesized via a polymer analogous reaction of poly(pentafluorophenyl acrylate). All copolymers were designed to exhibit a lower critical solution temperature (LCST) in water, which was only weakly dependent on the amount of incorporated chromophoric fulgimide groups. The copolymers showed a photocyclization of the fulgimide side groups upon irradiation with UV‐light accompanied with a color change. The closed form of the chromophore had a halftime of 136 min for the visible reisomerization and did not affect the LCST of the polymer. This led to the realization of a logic “NOT A” for the fulgimide containing PNIPAM, while a corresponding azobenzene containing PNIPAM resulted in a different logic “A implies B”.
992.
The scanning reference electrode technique (SRET) was used to characterize the corrosion behavior of carbon steel in the NaNO2-containing chloride solution and tap water. In 10−3 MNaNO2+10−3 MNaCl+10−3 MNa2SO4 solution, the passivated carbon steel surface suffered the pitting. In this case, the size of anodic and cathodic areas on the corroding surface varied with the exposed time, but anodic and cathodic sites did not change. On the contrary, the carbon steel was corroded generally in the tap water. The localized anodes and cathodes on the corroding surface were not fixed but movable with the exposed time during the whole corrosion process, and the “movable anodes” can be in situ monitored and momentarily identified by SRET measurements. 相似文献
993.
U. Guth F. Gerlach M. Decker W. Oelßner W. Vonau 《Journal of Solid State Electrochemistry》2009,13(1):27-39
The availability and application of solid-state reference electrodes for potentiometric electrochemical sensors are briefly
reviewed. For a long time, considerable efforts have been made to combine solid-state indicator electrodes with equivalent
reference electrodes to take advantage of the absence of liquid system components to full capacity. In spite of various suggestions
to solve the problem, no type of solid-state reference electrode is so far available with properties completely identical
to conventional ones. 相似文献
994.
Roa G Ramírez-Silva MT Romero-Romo MA Galicia L 《Analytical and bioanalytical chemistry》2003,377(4):763-769
This work reports the use of and -cyclodextrin-modified carbon paste electrodes (CPE-CD and CPE-CD) to determine simultaneously Pb(II) and Cd(II) by means of the electrochemical technique known as anodic stripping voltammetry (ASV). Both modified electrodes displayed good resolution of the oxidation peaks of the said metals. Statistic analysis of the results strongly suggests that the CPE-CD exhibited a better analytical response that the CPE-CD, while the detection limits obtained for Pb(II) were 6.3×10–7 M for the CPE-CD and 7.14×10–7 M for the CPE-CD, whereas for Cd(II) they were 2.51×10–6 M for the CPE-CD and 2.03×10–6 M for the CPE-CD. 相似文献
995.
This work deals with the Paschen law in electrical breakdown of gases at pd values around the Paschen minimum. From the Townsend model, it is possible to deduce theoretical forms of the coefficients in Paschen's law, of which our calculated values are in the range of the tabulated values from the literature. These formulae show that the breakdown voltage must be influenced by the inter‐electrode distance, while the product pd remains a key parameter. This is confirmed by the Paschen curves measured in an argon discharge for inter‐electrode distances varying from 2 to 9 cm (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
996.
共振隧穿二极管(RTD)可编程逻辑门是一种由单双稳态转换逻辑单元(MOBILE)及正、负输入分支组成的阈值逻辑电路。基于二进制神经元模型中的三层网络结构,提出了基于RTD可编程逻辑门的n变量函数实现算法。按照汉明距离由大到小的顺序,搜索最优输入向量,用定理1或定理2方法产生隐层函数,通过变换次数,确定输入向量的真假及隐层函数的权重。由于定义了最优输入向量及变换次数,提高了算法的准确性;又由于采用了定理2方法,令设计的电路更简单。 相似文献
997.
吡哌酸在玻碳电极上的伏安测定 总被引:3,自引:0,他引:3
本文应用线性扫描伏安法,微分脉冲伏安法,循环伏安法对吡哌酸在GCE上的伏安行为进行了研究,发现在磷酸盐缓冲溶液中+1.2V左右有一氧化峰,PPA的浓度2-100μg/ml与峰电流呈良好的线性关系。测定了胶囊和片剂中PPA的含量,RSD2.1%,回收率在97%-104%之间,方法操作简单快速。PPA在GCE上的电极反应属于不可逆过程。 相似文献
998.
QiuHongLI LinNIU ChangQiaoZHANG FengHuaWEI HuZHANG 《中国化学快报》2004,15(1):115-117
The oxidation of methanol was investigated on platinum-modified polyaniline electrode.Changes in the electrode rotation rates (Ω) during platinum electrodeposition remarkably affect the formation and distribution of platinum in the polymer matrix and consequently lead to different currents of methanol oxidation. The results show that platinum loading is proportional to rotation rates Ω^1/2. 相似文献
999.
Veena Misra Xiaoli Xu Brian E. Hornung Richard T. Kuehn Donald S. Miles John R. Hauser Jimmie J. Wortman 《Journal of Electronic Materials》1996,25(3):527-535
In the present study, we have performed electrical characterization of oxides deposited via rapid thermal chemical vapor deposition using SiH4 and N2O. We have investigated the effect of temperature, pressure, and SiH4 to N2O ratio on the electrical and material properties of as-deposited films. We have found that as-deposited oxides deposited at low temperatures, low pressures, and with a low silane to nitrous oxide ratio of ~0.5% give good material and electrical properties. The as-deposited films are stoichiometric in nature and have high deposition rates. As-deposited films had very low Dit values, high breakdown fields, and excellent subthreshold swing. The leakage currents and metal oxide semiconductor field effect transistor current drive, although lower than thermal oxides, were found to be quite acceptable. We have also investigated the thickness dependence of the films and found that as the film thickness is reduced below 50Å, the reliability improves for all oxides including the silicon-rich deposited oxides. 相似文献
1000.
CHEN Jing YU Chang-Shui SONG He-Shan 《理论物理通讯》2006,46(1):69-72
A kind of new operators, the generalized pseudo-spin operators are introduced and a universad intrinsic Hamiltonian of two-qubit interaction is studied in terms of the generalized pseudo-spin operators. A fundamental quantum gate U(θ) is constructed based on the universal Hamiltonian and shown that the roles of the new quantum gate U (θ) is equivalent, functionally, to the joint operation of Hadamard and C-Not gates. 相似文献