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61.
Lili Wei Joanna Borowiec Lihua Zhu Jingdong Zhang 《Journal of Solid State Electrochemistry》2012,16(12):3817-3823
We have investigated the interaction between diclofenac and deoxyribonucleic acid (DNA) by the electrochemical method. On glassy carbon electrode, the voltammetric curve of diclofenac showed an oxidation peak, which was obviously influenced by the addition of DNA. Accordingly, a series of electrochemical experiments were carried out to elucidate the interaction between diclofenac and DNA. Based on the diclofenac–DNA interaction, a biosensor for diclofenac was developed. When a film of DNA was immobilized on the electrode surface, DNA showed an oxidation signal promoted by graphene oxide. Due to the diclofenac–DNA interaction, the peak current of DNA decreased and the peak potential shifted positively with increasing the concentration of diclofenac. The response of the biosensor was linear to the concentration of diclofenac in the range of 1 to 130?μM. Using such a biosensor, the photodegradation of diclofenac was successfully monitored. 相似文献
62.
A rapid and selective reversed-phase liquid chromatography with fluorescence detection was developed and validated for the determination of toosendanin in the fruit of Melia azedarach. After extraction, the extracts were analysed at 25 °C using Eclipse XDB-C18 column (4.6 mm × 150 mm; 5 μm) and a mobile phase consisting of methanol–water at a flow rate of 1.0 mL min?1. Detection wavelength was set at λEx = 230 nm, λEm = 320 nm. The linearity, accuracy, and precision of the method were good, and the method can be successfully used to investigate the level of toosendanin component in herb samples with satisfactory results. 相似文献
63.
Accurate Monte Carlo tests of the stochastic Ginzburg-Landau model with multiplicative colored noise 总被引:1,自引:0,他引:1
A accurate and fast Monte Carlo algorithm is proposed for solving the Ginzburg-Landau equation with multiplicative colored noise. The stable cases of solution for choosing time steps and trajectory numbers are discussed. 相似文献
64.
Evaluation of a rapid method for the quantitative analysis of fatty acids in various matrices 总被引:1,自引:0,他引:1
A simplified method for quantitative analysis of fatty acids in various matrices by gas chromatography is proposed as an alternative to the conventional method and the variables of the protocol examined to optimize the processing conditions. The modified method involves direct methylation of fatty acids in homogenized samples with boron trihalide (BF(3) or BCl(3) in methanol) followed by extraction with hexane. The addition of hexane to the reaction mixture after the methylation process can enhance the efficiency of fatty acid methylation and is critical for those samples that contain high levels of triglycerides. A mechanism underlying this effect is proposed. 相似文献
65.
"Push-pull" phenyltetraene-based chromophores are too sensitive to be incorporated into Diels-Alder-type cross-linkable polymers due to the reactivity of its diene segment with maleimides. A facile synthetic route has been explored to incorporate a methoxy group into the R position of such chromophores, which reduces their diene reactivity during the poling and lattice hardening process. The poled polymers with one of such chromophores doped in a cross-linked polymer lattice showed ultrahigh electro-optic activities, up to 306 pm/V at 1310 nm. 相似文献
66.
Existence and asymptotic behavior of traveling wave solution for Korteweg-de Vries-Burgers equation with distributed delay 下载免费PDF全文
In this paper, we investigate the existence and asymptotic behavior of traveling wave solution for delayed Korteweg-de Vries-Burgers (KdV-Burgers) equation. Using geometric singular perturbation theory and Fredholm alternative, we establish the existence of traveling wave solution for this equation. Employing the standard asymptotic theory, we obtain asymptotic behavior of traveling wave solution of the equation. 相似文献
67.
根据电子注参数、布里渊磁场公式及周期聚焦系统轴向磁通密度峰值经验公式,计算出永磁聚焦系统轴向峰值磁通密度,利用Ansoft Maxwell 3D软件建立了四注行波管周期永磁聚焦系统仿真模型,对模型结构尺寸进行了参数化分析,研究了周期永磁聚焦系统结构尺寸对聚焦系统通道内磁通密度的影响,确定了磁聚焦系统结构最佳尺寸配合,优化设计出了四注行波管周期永磁聚焦系统。其电子注通道中心轴线上轴向磁通密度峰值Bz=309 mT,横向磁通密度Bt=2.86 mT,Bt/Bz=0.92%。 相似文献
68.
研制的永磁组件采用主辅永磁体和匀场技术相结合的改进C型磁路结构,利用计算机仿真技术对组件磁路结构进行验证及优化。仿真分析及实验结果表明:采用这种磁路结构扩大了均匀区的范围,提高了磁场均匀性。按这种结构制造的永磁组件在20 mm气隙、中心平面200 mm120 mm均匀区内气隙磁通密度达到0.75 T,不均匀度为0.67%。另外,也对永磁组件在高低温下的磁性能进行了仿真计算,结果表明:在-55~70 ℃温度范围内均匀区的气隙磁通密度变化为4%左右。 相似文献
69.
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