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41.
Bi Xian Tonghua Li Chen Kai Tongcheng Cao Jianrong Huang Yunpeng Qi 《Journal of mathematical chemistry》2004,36(2):129-138
Orthogonal signal correction (OSC) was a data preprocessing algorithm. It ensured that the filtered information was irrelevant to concentration data while using it to filter the noise from the original data. This paper extended the OSC application range from two-way data to three-way data. Two drug data sets, Enoxacin, Norfloxacin, Ciprofloxacin and Betamethasone, cortisone acetate, prednisone acetate, showed that the application of the OSC algorithm to three-way HPLC data was feasible and needed further research. 相似文献
42.
顺丁烯二酸二异辛酯的合成 总被引:4,自引:0,他引:4
以顺丁烯二酸酐和异辛酯为原料,用对甲苯磺酸作催化剂合成顺丁烯二酸二异辛酯。用正交试验确定了酯化反应的优化条件,酯化率达97.96%. 相似文献
43.
Lata Mathew Mundlapudi L. P. Reddy Tumkur R. Ramamohan Talasila Prasada Rao Chonatumatom S. P. Iyer Alathur D. Damodaran 《Mikrochimica acta》1997,127(1-2):125-128
This paper describes a sensitive spectrophotometric method for the determination of mercury, based on the flotation of a mercury iodide-brilliant green complex with cyclohexane at pH 5 and dissolution of the complex in acetone. The absorbance of the complex is measured at 625 nm. Beer's law is obeyed from 4–500 g/l of mercury. The method is highly sensitive ( = 5.96 × 105 1 mol–1 cm–1) and selective, as it is free from interferences by almost all cations and anions in the presence of EDTA. Furthermore, a two-level orthogonal array design as a chemometric method has been used for optimization of the various parameters involved. The method has been successfully applied to paper industry effluents. 相似文献
44.
45.
《Arabian Journal of Chemistry》2022,15(1):103472
As a representative of traditionally fermented Chinese medicine, Massa Medicata Fermentata (MMF) shows the functions of invigorating the spleen and stomach and promoting digestion, which plays an important role in the treatment of gastrointestinal diseases. The fermentation mechanism and the key factors that affect the quality of MMF have not been revealed yet, which has become an urgent issue that limits its clinical application. This article aims to systematically and comprehensively reveal the transformation of physical properties and the dynamic trend of chemical components including substrate components, volatile components, and lactic acid as anaerobic fermentation product during MMF fermentation. Along with obvious hyphae growth observed for MMF, the weight of MMF decreased, and the moisture and temperature increased. Through the quantified 14 components from substrate, ferulic acid increased from 45.53 ± 6.94 to 141.89 ± 78.40 μg/g, while glycosides and phenolic acids declined except caffeic acid. Also, within the 66 volatile components analyzed, alcohols and acids increased, while aldehydes and ketones decreased. Lactic acid was not detected in the fermentation substrate, but an apparent increase in lactic acid content was observed along with the increased fermentation days, resulting in 2.54 ± 0.15 mg/g on day 8. Based on the tested components, the fermentation process of MMF was discriminated into three distinct stages by principal component analysis, and an optimal fermentation time of four days was proposed. The results of this study will be of great significance to clarify the characteristics of fermentation and conduce to improving quality standards of MMF. 相似文献
46.
柠檬酸在D354树脂上的离子交换研究 总被引:5,自引:2,他引:5
研究了大孔型弱碱性阴离子交换树脂D354分离水中柠檬酸的相平衡和动力学。Langmuir方程能够良好地关联等温线。建立了离子交换过程的孔扩散模型,并以正交配置法与Gear法结合进行数据拟合。结果表明,液膜阻力对交换过程具有重大影响,简单线性推动力模型能够很好地描述液膜传质过程。 相似文献
47.
Recently, we introduced a class of generalized hypergeometric functionsI
n:(b
q)/α:(a
p) (x, w) by using a difference operator Δ
x,w
, where
. In this paper an attempt has been made to obtain some bilateral generating relations associated withI
n
ga
(x, w). Each result is followed by its applications to the classical orthogonal polynomials. 相似文献
48.
Joël Delville 《Applied Scientific Research》1994,53(3-4):263-281
Experiments are performed in an incompressible plane turbulent mixing layer, using various hot wire rake configurations. From these experiments, the Proper Orthogonal Decomposition is applied for kernels where the space-time correlation tensor is evaluated over different spatial meshes and velocity components configurations. The resulting decompositions are then discussed in terms of characterization of the organization of the flow for various scalar or vectorial approaches of the POD. An incrtial range law is evidenced. The instantaneous contribution of the first modes of the POD to the organization of the flow is analyzed. A dynamical behavior for the organization of the flow is observed from the correlation between the first two modes contribution. 相似文献
49.
We study the convergence of rational interpolants with prescribed poles on the unit circle to the Herglotz-Riesz transform of a complex measure supported on [–, ]. As a consequence, quadrature formulas arise which integrate exactly certain rational functions. Estimates of the rate of convergence of these quadrature formulas are also included.This research was performed as part of the European project ROLLS under contract CHRX-CT93-0416. 相似文献
50.
We describe a parallel and efficient synthesis of multi-branched oligosaccharides 3a-g based upon the structure of the phytoalexin elicitor active branched pentasaccharide 2. One-pot sequential orthogonal deprotection of tetrasaccharide 5 with three different protecting groups provided each of seven glycosyl acceptors 4a-g. Glycosylation of the acceptors 4a-g, followed by deprotection provided branched oligosaccharides 3a-g. All the reaction processes from scaffold 5 to 3a-g except for final hydrogenolysis were achieved utilizing an automated synthesizer in a parallel fashion. 相似文献