共查询到20条相似文献,搜索用时 109 毫秒
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手性金属Salen配合物在不对称催化中的应用* 总被引:12,自引:3,他引:9
手性Salen金属配合物已在不对称催化中得到了广泛的应用。本文主要介绍了可溶性的手性金属Salen配合物在不对称催化反应中的应用以及手性金属Salen配合物固载化研究取得的进展。 相似文献
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综述了近年来手性流动相添加剂在高效液相色谱拆分对映体中的应用,阐述了各类手性流动相添加剂的拆分机理及其在药物分析中的应用,引用文献52篇. 相似文献
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手性1,2-二苯基-1,2-乙二胺及其衍生物在不对称合成中的应用 总被引:2,自引:0,他引:2
含有C2 对称轴的1,2-二胺在不对称合成中得到了广泛的应用.综述了手性1,2-二苯基-1,2-乙二胺及其衍生物的合成,以及作为手性辅助基和手性配体在不对称合成中的应用. 相似文献
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The transfer-matrix method is used to describe the occupation of a lattice of sites in equilibrium with bulk solution, thus giving a model for adsorption from solution (or binding or reaction). Numerical illustration is given using the zeroth approximation of the quasi-crystalline model for the bulk phase. Application of the method to two-dimensional systems involving orientation effects and phase changes is briefly discussed. 相似文献
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Application of the explicit finite-difference simulation method to linear-sweep cyclic voltammetry in the case of non-first-order electrode reactions is described. Reversible, quasi-reversible and totally irreversible electrode reactions with reaction orders > 1 or < 1 are discussed. Simple criteria for evaluating the kinetic parameters are proposed. The accuracy of the proposed method is checked by comparing the results obtained with literature data. 相似文献
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用近红外光谱仪快速测定调和汽油中芳烃、烯烃的含量 总被引:5,自引:0,他引:5
介绍了带有CCD检测器的近红光普仪在调和汽油分析中的应用,并与标准测定方法测定的数据对比,验证了近红外光谱法测定汽油性质的可靠性,同时表明该方法具有分析速度快,重现性好等特点。 相似文献
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Ann-Christine Albertsson Camilla Barenstedt Sigbritt Karlsson 《Journal of chromatography. A》1995,690(2):207-217
A solid-phase extraction (SPE) method using unbonded silica (Si) and silica bonded with octadecyl (C18) or aminopropyl (NH2) groups was developed to separate into five fractions the highly complex mixture of low-molecular-mass degradation products formed from degradable polymers. Application of the method to polyethylene modified with starch and/or a pro-oxidant system, degraded for 30 weeks in water at 95°C, enabled the identification by GC-MS of over three times as many products as when the sample was prepared by liquid-liquid extraction. Over 60 degradation products were identified in each sample; mainly dicarboxylic acids, monocarboxylic acids and n-alkanes. In addition, several lactones, aldehydes and alcohols were detected. 相似文献
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H Hosotsubo 《Journal of chromatography. A》1989,487(2):421-427
A high-performance liquid chromatographic method has been developed for the quantitative analysis of vancomycin in plasma. The method involves protein precipitation with acetonitrile, followed by normal-phase chromatography on an aminopropyl column. The clear supernatant was injected after centrifugation, and the eluent was monitored at 240 nm. No interference was found either with endogenous substances or with many currently used drugs, indicating a good selectivity for the procedure. The standard curve was linear between 0.1 and 100 micrograms/ml, and the detection limit was 0.01 microgram/ml of plasma. The mean intra- and inter-assay coefficients of variation were 2.4 and 4.0%, respectively, in the 10-50 micrograms/ml range. Application of the method to the study of vancomycin pharmacokinetics in a rabbit after a single intravenous dose is also reported. 相似文献
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Rapid gas chromatography-mass spectrometry screening method for human pharmaceuticals, hormones, antioxidants and plasticizers in water 总被引:1,自引:0,他引:1
A rapid gas chromatography-mass spectrometry (GC-MS) method was developed and validated allowing quantification at the ng/l level of 19 analytes in water including human pharmaceuticals, hormones, antioxidants and a plasticizer. On-line continuous liquid-liquid extraction with dichloromethane of 10-401 unfiltered water samples was used to achieve a 10000-40000-fold concentration factor. No sample cleanup or derivatization was required. Recoveries ranged from 57 to 120%. Application of the method to water recycling plant effluent demonstrated the presence of nearly all targeted compounds at ng/l to microgram/l levels. Screening for nontarget compounds in the treated effluent samples indicated the method could be readily extended to include additional analytes. 相似文献
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A simple and sensitive isocratic liquid chromatographic method was developed for the analysis of isovaleric and valeric acids in human urine as biomarkers in metabolic acidosis. The method is based on the derivatization of isovaleric and valeric acids with a fluorescent reagent 2-(2-naphthoxy)ethyl-2-(piperidino)ethanesulfonate for labeling the analytes with the naphthoxy fluorophore. The resulting fluorescent derivatives of isovaleric and valeric acids were separated on a phenyl-hexyl column, using a mixed solvent of methanol-water-tetrahydrofuran (55:31:14, v/v) as the mobile phase. The separated derivatives were monitored with a fluorimetric detector (excitation at 225 nm and emission at 360 nm). The linear range of the method for the determination of isovaleric acid or valeric acid derivative was over 0.2 approximately 8.0 microM. The detection limit (signal to noise ratio=3 with 10 microl injected) of isovaleric acid or valeric acid was about 0.04 microM. Application of the method to the analysis of isovaleric acid in the urine of a patient with isovaleric acidemia proved feasible. 相似文献
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J. C. W. Chien T. Kohara C. P. Lillya T. Sarubbi B-H. Su R. S. Miller 《Journal of polymer science. Part A, Polymer chemistry》1980,18(8):2723-2729
A mild, efficient method of nitrating olefins was described recently by Corey and Estreicher. Application of their procedure to diene polymers failed because of the insolubility of the hydrophobic polymer in the aqueous nitromercuration regent. Use of water-immiscible organic cosolvents gave slow nitromercuration with substantial formation of nitrite esters. To overcome these problems a nonaqueous phase transfer-assisted method of rapid selective nitromercuration of diene polymers was developed. 相似文献
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Przemysław Podulka 《Surface and interface analysis : SIA》2020,52(12):875-881
In this paper, the bisquare robust polynomial fitting (BSRPF) method for surface texture features assessment was proposed. Plateau-honed cylinder liner bronze surfaces with additionally burnished microcavities (defined as dimple, holes, and/or cavities) were taken into consideration. Analyzed details were measured with stylus (Talyscan 150) or white light interferometer (Talysurf CCI Lite) methods. It was assumed that application of commonly used (in surface contact and noncontact measurement technology) polynomial fitting procedures did not allow to extract required features; distortion of microreservoir dimples for oil consumption assessment was falsely estimated when valleys were near edge or on the edge located. Application of bisquare robust polynomial fitting method caused a minimization of microflattens of dimples irrespective of valley distribution; the biggest degree of polynomial fitting method applied, the minimal distortions of oil reservoirs were noticed. The valley size (depth and width) and valley-to-valley distance were also taken into account. 相似文献
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A simple micellar electrokinetic chromatographic (MEKC) method is described for the simultaneous separation of twelve cephalosporin antibiotics. The separation was performed in a phosphate buffer (0.1 M, pH 6.6) with sodium dodecyl sulfate (SDS) (0.1 M) as an anionic surfactant. The complete separation of twelve cephalosporins was attained in 36 min. Application of the method to the quantitative analysis of cefuroxime, cephalexin, cephapirin and cephradine in pharmaceutical preparations was demonstrated. 相似文献