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51.
一种基于二进小波变换的自适应滤波方法 总被引:3,自引:0,他引:3
根据信号和噪声经小波变换后在不同尺度上有不同的特征,将相邻尺度二进小波变换值的相关量进行归一化处理并与小波变换值比较来判断信号与噪声,以噪声在各尺度的方差作为终止迭代的标准,提出了一种基于二进小波变换小波域选择噪声的自适应滤波方法。研究了模拟信号的去噪过程、半峰宽和信噪比对去噪结果的影响,并对模拟含噪信号和含噪毛细管电泳信号去噪前后的结果进行了比较。实验结果表明:由于该方法具有良好的自适应性和显著的滤波效果,必将得到广泛的应用。 相似文献
52.
《Analytical letters》2012,45(16):1857-1862
Abstract A liquid chromatographic differential refractive index detector (RI) and an ultraviolet absorption (at 195 nm) detector (UV) were studied for detection of triglyceride (TG) and phospholipid (PL) molecular species. It was found that the log UV/RI detector response ratio was linearly related to the log of the number of conjugated double bonds (degree of unsaturation) of the lipid in a predictable fashion, indicating the usefulness of the combination of both detectors in TG and PL analysis. The detection limit of the RI detector for TG and PL was found to be 5 × 10 ?7 M or as sensitive as the UV detector for saturated TG and PL. 相似文献
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Jun-Ichi Kikuchi Yukito Murakami 《Journal of inclusion phenomena and macrocyclic chemistry》1998,32(2-3):209-221
Steroid cyclophanes, bearing four bile acid moieties covalently placed on a tetraazaparacyclophane skeleton, were designed and synthesized as artificial cell-surface receptors. Guest-binding behavior of the steroid cyclophanes embedded in a bilayer membrane formed with a synthetic peptide lipid was clarified by means of fluorescence and circular dichroism spectroscopy. We found that the steroid cyclophane effectively bound aromatic guests in both bilayer membranes and aqueous solution. In addition, copper(II) ions acted as a guest species for the steroid cyclophane and a competitive inhibitor toward a NADH-dependent lactate dehydrogenase (LDH). On these grounds, we constituted a supramolecular assembly as an artificial signaling system in combination with the steroid cyclophane, a cationic peptide lipid, and LDH. As a consequence, the steroid cyclophane acted as an effective artificial cell-surface receptor being capable of transmitting an external signal to the enzyme in collaboration with copper(II) ions as a signal transmitter. 相似文献
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研究了高效液相色谱-火焰原子吸收光谱联用系统分析信号处理方法,比较了各种处理方法的优缺点,用积分与适应平滑法综合处理色谱峰分析信号,不仅能有效地消除噪声,而且能使分析信号得到加强,以测定镍为例,经积分与适应平滑法综合处理后,检出限改善了2.7倍。 相似文献
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Wavelet-Fourier self-deconvolution 总被引:5,自引:0,他引:5
Using a wavelet function as the filter function of Fourier self-deconvolution, a new method of resolving overlapped peaks, wavelet-Fourier self-deconvolution, is founded. The properties of different wavelet deconvolution functions are studied. In addition, a cutoff value coefficient method of eliminating artificial peaks and wavelet method of removing shoulder peaks using the ratio of maximum peak to minimum peak is established. As a result, some problems in classical Fourier self-deconvolution are solved, such as the bad result of denoising, complicated processing, as well as usual appearance of artificial and shoulder peaks. Wavelet-Fourier self-deconvolution is applied to determination of multi-components in oscillographic chronopotentiometry. Experimental results show that the method has characteristics of simpler process and better effect of processing. 相似文献
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It is often desirable to selectively remove corrupting or uninteresting signals from complex NMR spectra without disturbing overlapping or nearby signals. For biofluids in particular, removal of solvent and urea signals is important for retaining quantitative accuracy in NMR‐based metabonomics. This article presents a novel algorithm for efficient filtering of unwanted signals using the filter diagonalization method (FDM). Unwanted signals are modeled in the time domain using FDM. This modeled signal is subtracted from the original free induction decay. The resulting corrected signal is then processed using established workflow. The algorithm is found to be reliable and fast. By eliminating large, broad, uninteresting signals, many spectra can be subjected to fully automated absolute value processing, allowing objective preparation of spectra for pattern recognition analysis. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献