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利用二元体系的C-H红外光谱推算汽液平衡数据 总被引:1,自引:0,他引:1
Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is not economical. The infinite dilution activities can be used to predict VLE. However, it needs both thc ends of the activities that are difficult to obtain for many systems. In the present study, a new model is proposed for correlating the frequency shift of C-H stretching band of IR spectra over the whole concentration. Investigated mixtures include water/2-propanol, water/N, N-dimethylformamide (DMF), water/methanol, water/ethanol, water/1, 4-dioxane,and water/dimethylsulfoxidc (DMSO) systems. Simultaneous correlations of C-H frequency shift and VLE data arc made. Furthermore, the VLE data were predicted with satisfactory results by the parameters obtained from IR spectra coupled with one of the infinite dilution activity coefficients. 相似文献
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经验模态分解(empirical mode decomposition,EMD)以其自适应的滤波特性和多分辨率在很多非线性研究领域得到广泛应用,但在分解过程中常会出现虚假分量。针对此问题,基于信息论的知识提出利用K-L散度(Kullback-Leibler divergence,K-L)的虚假分量识别方法。该方法先将原始信号分解成若干个本征模态函数(intrinsic modefunction,imf),再分别计算原始信号与imf分量之间的K-L散度,然后将所求的K-L散度值从小到大排序,对应于较大K-L散度值的imf分量被视为虚假分量,可以去除。实验证明,该方法能够明显地区分出真实信号与虚假分量,准确而快速的得到信号的真实成分,消除虚假分量的影响。 相似文献
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提出了基于内禀模态信息熵与支持向量机的转子振动故障诊断方法。采用EMD方法将转子振动信号分解为若干个内禀模态分量,由各个内禀模态分量的信息熵构成转子状态的特征参数。采用支持向量机分类器对故障类型进行分类。通过转子试验台的仿真实例证明了该方法的有效性。另外,在特征提取环节对比采用了传统的Fourier变换法,结果体现了EMD方法在非线性和非稳态信号处理上的优越性。 相似文献
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Prediction of vapor-liquid equilibrium (VLE) is extremely necessary to separate liquid mixture in chemical production, especially when the required experimental data are difficult to measure, or the measurement is not economical. The infinite dilution activities can be used to predict VLE. However, it needs both the ends of the activities that are difficult to obtain for many systems. In the present study, a new model is proposed for correlating the frequency shift of C-H stretching band of IR spectra over the whole concentration. Investigated mixtures in- clude water/2-propanol, water/N, N-dimethylformamide (DMF), water/methanol, water/ethanol, water/1, 4-dioxane, and water/dimethylsulfoxide (DMSO) systems. Simultaneous correlations of C--H frequency shift and VLE data are made. Furthermore, the VLE data were predicted with satisfactory results by the parameters obtained from IR spectra coupled with one ot the intinite chlution activity coefficients. 相似文献
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针对有源电力滤波器(active power filter,APF)的直流侧电压控制问题,基于传统比例积分(proportional integral,PI)控制方法控制精度低,存在超调和快速性这一矛盾,自抗扰控制(active disturbance rejection control,ADRC)因引入干扰补偿,大大提高其抗干扰能力。但目前单一的优化算法整定ADRC参数不能提高控制精度及响应速度,现提出通过改进天牛须算法(beetle antennae search,BAS)来优化自抗扰控制器参数的方法,将变异环节引入天牛须算法,使其跳出局部搜索,更快搜索得到全局最优解,并提高精度的同时兼顾响应速度,搭建MATLAB/Simulink仿真以及充电桩谐波治理的APF实验平台进行验证,通过实验验证,该算法优化后能够减少超调,实现电流的精确跟踪,其谐波率从3.32%降低到1.34%,证实算法的有效性。 相似文献
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醋酸乙醇胺离子液体的合成及其溶液体系粘度和电导率的测定与关联 总被引:1,自引:0,他引:1
采用酸碱中和法合成了醋酸乙醇胺离子液体(EOAA),在298.15 K时,测定了全浓度范围内EOAA/水、EOAA/DMSO以及EOAA/正丁醇3种二元溶液的粘度和电导率。结果表明,3种溶剂都能明显地降低离子液体的粘度,并且粘度偏差Δη均为负值。随着离子液体物质的量分数增加,溶液电导率的变化呈现先增加后减小的趋势。同时,对比了3种溶剂的异同。结果显示,介电常数较大的溶剂对离子液体的粘度及电导率的影响更加显著。此外,分别采用RedlichKister和Castell-Amis方程对溶液的粘度偏差及电导率进行了拟合关联。 相似文献
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葡萄球菌对发酵肉制品中生物胺降解机制研究进展 总被引:1,自引:0,他引:1
近年来,发酵肉制品因具有营养、美味等优点而深受消费者追捧,但发酵肉中常会存在生物胺,引发人们对其安全性的关注。生物胺是一类具有生物活性的低分子含氮有机化合物,适量剂量范围的生物胺有助于人体生长、增强代谢,过量则可能导致产生过敏、腹泻、致畸甚至死亡等不良反应。本文综述葡萄球菌降低发酵肉中生物胺含量的3 种机制:生物胺氧化酶氧化、菌株产生葡萄球菌素以及与其他菌株协同作用来控制发酵肉制品中生物胺含量。通过利用葡萄球菌降胺作用,为食品中生物胺的防控与消除提供思路。 相似文献
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