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21.
《Electroanalysis》2002,14(24):1699-1706
An application of a partial least squares calibration method for the simultaneous voltammetric determination of indomethacin, acemethacin, piroxicam and tenoxicam is suggested. It was shown that it is possible to resolve complex mixtures of analytes even when they have strongly overlapped signals. In order to check the proposed method, statistical analysis of the results was performed by mean of hypothesis tests. The method developed was applied to the electrochemical reduction region of four anti‐inflammatory drugs and allowed the drugs to be quantified at concentrations between 0.52 and 4.09 μg mL?1 for acemethacin, 0.44 and 3.50 μg mL?1 for indomethacin, 0.43 and 3.40 μg mL?1 for piroxicam, and 0.42 and 3.30 μg mL?1 for tenoxicam with good results. The average absolute value of relative errors was 2.25%, 4.31%, 1.68% and 2.49%, respectively. 相似文献
22.
We study the rate of convergence in a limit theorem due to Kabanov-Liptser-Shiryayev. We show how the probabilities P(N t= k) can be computed from the compensator, when it is deterministic. 相似文献
23.
Chong-Kwang Lee Soon-Sik Kwon Seung-Tae Shin E-Joon Choi Soonnam Lee Liang-Chy Chien 《Liquid crystals》2013,40(8):1007-1013
Banana-shaped achiral compounds, the 1,3-phenylene bis[4-(alkenyloxyphenyliminomethyl)benzoate]s, were synthesized with varying length of the alkenyl group; their ferroelectric properties are described. The smectic mesophases, including a switchable chiral smectic C (SmC*) phase, were characterized by differential scanning calorimetry, polarizing optical microscopy and the triangular wave method. The presence of vinyl groups at the ends of the linear side-wings in the banana-shaped achiral molecules, containing a Schiff's base mesogen, induced a decrease in melting temperature and formation of the switchable SmC* phase in the melt. The compound having the octenyloxy group exhibited a spontaneous polarization of 120 nC cm?2 on reversal of an applied electric field. 相似文献
24.
Pei Dang 《Mathematical Methods in the Applied Sciences》2015,38(2):365-379
In this study, we propose some new uncertainty principles for periodic signals with sharper lower bounds than those in the existing ones. The improved lower bounds, in particular, are related to the frequency of the signal. Three examples are employed to demonstrate sharpness of the new uncertainty principles. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
25.
通过对由纳米磁流体运动引起的双扫描激光散斑干涉光场及其变化做拉盖尔-高斯滤波下的傅里叶变换,获得动态散斑干涉图对应的光学涡旋分布及变化特征。分析认为,光学涡旋分布及变化对应着由纳米磁微粒及其团族的运动所引起的动态散斑变化。当纳米磁微粒聚集到分散的过程中,动态激光散斑光场的奇异场分布发生相应变化,说明了磁流体运动过程对应涡旋密度有先大后小,再由小变大的两个变化;并且光学涡旋密度高,对应较小颗粒的散斑场,磁流体处于稳态的状况;光学涡旋密度低,对应较大颗粒的散斑场,对应着磁流体激烈的运动。研究结果体现了奇异场分布变化和纳米磁流体动后趋稳的过程存在对应关系。 相似文献
26.
Fernando Soto Daniel Kupor Miguel Angel Lopez‐Ramirez Fanan Wei Emil Karshalev Songsong Tang Farshad Tehrani Joseph Wang 《Angewandte Chemie (International ed. in English)》2020,59(9):3480-3485
A multifunctional motile microtrap is developed that is capable of autonomously attracting, trapping, and destroying pathogens by controlled chemoattractant and therapeutic agent release. The onion‐inspired multi‐layer structure contains a magnesium engine core and inner chemoattractant and therapeutic layers. Upon chemical propulsion, the magnesium core is depleted, resulting in a hollow structure that exposes the inner layers and serves as structural trap. The sequential dissolution and autonomous release of the chemoattractant and killing agents result in long‐range chemotactic attraction, trapping, and destruction of motile pathogens. The dissolved chemoattractant (l ‐serine) significantly increases the accumulation and capture of motile pathogens (E. coli) within the microtrap structure, while the internal release of silver ions (Ag+) leads to lysis of the pathogen accumulated within the microtrap cavity. 相似文献
27.
28.
Research on identifying the order of fringe pattern traces using angular scan and zone search method
A method for automatically identifying the order of fringe pattern traces is presented. It uses the simplified Otsu algorithm for obtaining the threshold, the angular scan in the range of 45~ for searching the trace positions, and the zone search technique for identifying different traces. Experimental results show that the proposed method may reliably obtain the order of fringe pattern traces orientating from almost 45° to 90°. 相似文献
29.
A. A. Hakhoumyan V. Zh. Tovmasyan H. S. Haroyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2008,43(3):125-130
Possibility to record B-FSK signals with use of stochastic resonance is studied. A Schmidt trigger is employed as bistable stochastic resonator. A digital model of the detector is proposed and quantitative results are obtained by means of simulations. Dependence of the probability of correctly detected bits on the added noise power and on the low-pass filter cutoff frequency is studied. Also the stability of the detector with respect to channel-introduced phase shifts is revealed. 相似文献
30.
A superluminal signal velocity (i.e. faster than light) is said to violate causality. However, superluminal signal velocities have been measured in tunneling experiments recently. The classical dipole interaction approach by Sommerfeld and Brillouin results in a complex refractive index with a finite real part. For the tunneling process with its purely imaginary refractive index this model obtaines a zero-time traversing of tunneling barriers in agreement with wave meechanics. The information of a signal is proportional to the product of its frequency band width and its time duration. The reasons that superluminal signal velocities do not violate causality are: (i) physical signals are frequency band limited and (ii) signals have a finite time duration. 相似文献