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膜的动电特性研究中,往往采用流动电位方法。该方法中,Ag-Ag Cl测试电极的质量是影响测试准确性的关键要素。本文采用正交试验设计和方差分析,着重考察电解法制备Ag-Ag Cl电极过程中,电流强度(I)、氯化时间(t)、电解质溶液浓度(CHCl)、电极来源(n)、烘烤温度(T)、活化电极溶液浓度(CKCl)等因素对Ag-Ag Cl电极稳定性的影响。得到Ag-Ag Cl电极的最优制备参数为:电流密度3.0m A/cm2,氯化时间50min,盐酸浓度0.1mol·L-1,烘烤温度120℃,活化电极溶液(KCl)浓度0.001mol·L-1;最显著影响因素为电极来源,显著影响因素为氯化时间和烘烤温度。对最优条件组合下制备的AgAg Cl电极,进行了稳定性实验,结果表明:制备的电极具有较好的稳定性,24h内电极电位漂移量小于0.10mv,7天内电极电位漂移量小于0.2mv;在聚偏氟乙烯中空纤维超滤膜流动电位测试中,流动电位与流动压差具有良好的线性和可重复性,回归曲线R20.99,变化规律符合Helmholtz-Smoluehowski公式,可以较好满足膜的流动电位测试要求。 相似文献
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In this paper, we show the attainability of KdV equation from some types of nonlinear Schrödinger equation by using multiscale expansions discretely. The power of this manageable method is confirmed by applying it to two selected nonlinear Schrödinger evolution equations. This approach can also be applied to other nonlinear discrete evolution equations. All the computations have been made with Maple computer packet program. 相似文献
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The ultrasonic signals in long bones contain multiple guided modes which are mutual superposed.The velocities of guided waves in long bones are very sensitive to cortical thickness (CTh).In this paper,Hilbert-Huang transform(HHT) was proposed to analyze multi-mode guided waves,which can decompose superposed waves into many independent modes.Then the group velocity of each mode was obtained at corresponding frequency,which was compared with the results of short time Fourier transform(STFT).The CTh was also obtained by comparing with the theoretical calculation.The results showed that the experimental determined thickness was in agreement with the actual CTh,indicating that measuring the velocity of the guided mode can be used to estimate the CTh.The HHT is an effective method to identify multimode guided waves. 相似文献
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David R. Turner Dr. Joshua Strachn‐Hatton Stuart R. Batten Prof. Dr. 《无机化学与普通化学杂志》2009,635(3):439-444
The synthesis and structure of the hydrated mono‐ and di‐potassium salts of benzenepentacarboxylic acid are reported – [K(H4BPC)(H2O)2]·(H2O) 1 and [K2(H3BPC)(H2O)3]·(H2O) 2 (BPC = benzenepentacarboxylate). In both instances the structures are complex coordination networks, predominantly containing η1 binding modes of the carboxylate and carboxylic acid groups, although bridging (O,O) and (O,O′) carboxylates and μ2‐H2O ligands also feature. Extensive hydrogen bonding is present through the carboxylic acid groups and both coordinated and interstitial water molecules. 相似文献
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Abstract For phase transition studies, neutron powder diffraction offers a number of important advantages over x-ray based techniques, for example ab-initio structural determination. There are two distinct methods using either monochromatic angular dispersive geometry on a reactor cold source or time-of-flight energy-dispersive techniques requiring a pulsed neutron source. Both techniques offer comparable resolution but have differing advantages for high pressure studies. Recent studies illustrate the benefits of the two methods and the application of these to solve unknown crystal structures. 相似文献