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1.
杨学谨  陈寿山 《分析化学》1996,24(5):591-594
在薄层色谱中分离一系列二茂铪化合物,首先利用黄金分割优选法优化二元展开剂体系,然后按优化结果把二元展开剂混合成四元溶剂体系,共用重叠分辨率法确定四元展开剂体系的最佳组成,分离结果令人满意,同时,本文还对等溶剂强度条件和不等溶剂强度条件下的优化结果做了比较和讨论。  相似文献   

2.
高效液相色谱-核磁共振联用技术及其应用   总被引:5,自引:1,他引:5  
高效液相色谱-核磁共振(HPLC-NMR)在线联用技术是同时进行未知混合物的分离和结构鉴定的最好手段之一。详细介绍了在HPLC-NMR联用技术中1H谱的分辨率、检测限和多重溶剂峰抑制的最新进展,并简要评述了其它分离方法与NMR联用情况  相似文献   

3.
高效液相色谱-核磁共振联用技术及其应用   总被引:3,自引:0,他引:3  
高效液相色谱-核共共振在线联用技术是同时进行未知混合物的分离和结构鉴定的量好手段之一。详细介绍了在HPLC-NMR联用技术中H谱的分辨率,检测限手多重溶剂峰抑制的最新进展,并简要评述了其它分离方法与NMR联用情况。  相似文献   

4.
提出柱前衍生非水毛这电泳分离金属离子的方法,应用新合成的2-(6-甲基-2-苯并噻唑偶氮)-5-二乙胺基酚作为柱前衍生试剂,乙醇和N,N-二甲基甲酰胺为非水溶剂,在6min内实现了钴、镍和铜的分离,灵敏度高,检测限分别为9.18×10^-8mol/L、2.79×10^-7mol/L和4.47×10^-7mol/L,考察了柱前衍生条件、非水溶剂配比以及分离参数对分离的影响。  相似文献   

5.
1-硝基蒽醌的高效液相色谱分析   总被引:1,自引:0,他引:1  
用V(N,N-二甲基酰胺):V(1,4-二氧六环):V(二甲基亚砜)=5:2:1混合溶剂溶解试样,利用Waters Nova-pak C18色谱柱,以1,4-二氧六环/甲醇/水=15/45/40(体积比)混合溶液为流动相,对1-硝基蒽醌样品进行了高效液相色谱法分离与分析研究。在所确定的色谱分离体系中,样品中各组分全部出峰且基本上达到基线分离,对定量方法进行了讨论,加标回收率除1,7-二硝基蒽醌外其  相似文献   

6.
通过官能团偶联反应,将端基改性为醛基的甲氧基聚乙二醇(分子量分别为2000、5000),按不同配比与甲壳胺反应,制得了甲壳胺接枝PEG的产物(Chitosan-g-PEG)。讨论了反应的最佳pH条件。建立了有效的产物分离方法,用红外光谱法、1H-NMR法对产物的本体结构进行了表征,并用元素分析法和1H-NMR法对接枝量进行了测定。  相似文献   

7.
重叠伏安峰的样条卷积法分辨   总被引:1,自引:0,他引:1  
建立了分辨重叠峰的样条卷积法;利用三阶样条函数构成的峰分辨函数与原信号进行卷积,直接对重叠的伏安峰进行处理,取得了较好的结果;被处理的重叠峰可达到其线分离,且峰位置的相对误差小于3.0%(完全重叠峰为5.4%),峰面积的相对误差小于2.0%;应用于镉(Ⅱ)-铟(Ⅲ)实验体系的微分脉冲伏安信号处理,取得满意的结果。  相似文献   

8.
本文建立了适于高效液相色谱的“Improved-PRISMA”优化系统,利用全范田二元线性梯度淋洗进行溶剂强度的优化,只需一次实验即可得知所需溶剂的最佳强度,简化了原“PRISMA”系统选择溶剂强度的过程。将此系统用于七个有机磷化合物的分离,得到了满意的结果。  相似文献   

9.
利用核磁共振氢谱测定了重柴油中芳烃抽提流程各控制点的组分,绘制了油/N-甲基吡咯烷酮(NMP) 和水/NMP体系的标准曲线,发现由此可以计算油品的组成。结果表明,该法可用于生产工艺控制流程中。最后对 溶剂的循环利用作出了评价。  相似文献   

10.
研究了对-N,N-二甲氨苯乙烯和蒽乙烯生成的激基缔合物在不同极性溶剂中的荧光特性,发现其荧光发射波长随溶剂的极性增大向长波方向移动,且发现激基缔合物荧光量子产率的大小决定对-N,N-二甲氨苯乙烯和蒽乙烯的光环加成产物的产率,其中反式产物的相对产率随溶液极性增大而降低,并进一步探讨了此光环加成反应的机理。  相似文献   

11.
Summary An appropriate optimization strategy should be able to find good separation conditions in the shortest time with only a few experiments, to assure the baseline-separation of all components. In this paper, the use of two optimization schemes has been studied using 10 substituted benzene as model compounds. The triangular overlapping resolution mapping (ORM) scheme and cubic ORM scheme were compared to optimize the three relevant parameters-the concentration of surfactant, the concentration of HP-β-cyclodextrin and pH. By conducting experiments that span the maximum working range of the system, overall optimum conditions for separation can be obtained. To confirm the validity of the two ORM schemes, additional experiments using the predicted optimum conditions were performed. Finally, 10 substituted benzene compounds were completely separated within 20 min by both sets of optimized conditions.  相似文献   

12.
The use of an interpretative optimization method to predict optimum conditions for the supercritical fluid chromatographic separation of nitroaromatics is demonstrated. The scheme utilizes the overlapping resolution mapping (ORM) procedure for multivariate prediction of the pressure gradient and temperature in order to separate eight nitroaromatics. Using the ORM scheme, only seven experiments were conducted before a global optimum was revealed. All the peaks were satisfactorily separated using experimental conditions derived from the scheme.  相似文献   

13.
Summary The overlapping resolution map method (ORM) formerly developed for simultaneous peak separation in chromatography has been modified and applied to multivariate optimization in atomic spectroscopy. It has been found that the method works very well for the simultaneous optimization of a set of signal intensities of m analytes in optical emission spectroscopy (OES) as functions of p independent spectroscopy variables, e.g. measuring conditions. The method works especially well in connection with computer graphics for up to three variables because the optimization results may be directly visualized. The experimental example under study was the optimization of the current intensity of the electrical arc and the concentration of NaCl as spectrochemical addition for the simultaneous determination of Cu, Mn, Si, Cr, Fe and Mg traces in highly purified Al2O3 powder by direct solid state OES.  相似文献   

14.
The carbohydrate moiety of the orosomucoid (ORM) molecule shows microheterogeneity [1] and the pteridine-containing variant seems to be tumor-specific [2-4]. However, there also exists a genetic (protein-related) polymorphism coded by the ORM1 and ORM2 loci on chromosome 9 [5, 6]. To investigate the relationship between ORM1 gene products and the development of carcinoma, we analyzed the ORM1 phenotypes of desialated sera from 125 patients with carcinoma. The allele frequencies were estimated for ORM1*F1 0.556, ORM1*F2 0.012 and ORM1*S 0.432. In comparison to healthy individuals from the same geographical area [6] the ORM1 S phenotypes are significantly more frequent in carcinoma patients. The patients' sera frequently showed additional ORM-positive proteins which focused slightly cathodically to the ORM 2 A band. These proteins may represent posttranslational modifications of the ORM1*S allele product. Whether these modifications are tumor-specific and related to the carbohydrate moiety of the molecule must be confirmed in further studies.  相似文献   

15.
The genetic polymorphisms of orosomucoid, ORM1 and ORM2, were analyzed by isoelectric focusing on polyacrylamide gels and subsequent immunoprinting. Sera from 600 unrelated individuals in Taiwan and Japan were examined. Five new alleles, designated ORM1*7, ORM1*8, ORM1*4.2, ORM2*8 and ORM2*10, were observed together with common and rare alleles that have been found in the Japanese and the Filipinos. As compared with the Japanese, the Taiwanese have a higher frequency of ORM1*1, and a significantly lower frequency of ORM1*2.1.  相似文献   

16.
Genetic polymorphism of orosomucoid (ORM) has been demonstrated in several populations and comprises two structural gene loci, ORM1 and ORM2. In Caucasians three common ORM1 alleles have been shown, while the ORM2 locus is almost monomorphic. ORM1 phenotyping by isoelectric focusing in agarose or polyacrylamide gel combined with either print immunofixation or enzyme-linked immunoblotting is described, and population and family data from Denmark and Southern Germany are given. It is proposed to use a different alpha-numerical nomenclature for the phenotypes of the ORM1 and ORM2 systems.  相似文献   

17.
Genetic variants of human plasma alpha-1 acid glycoprotein (AGP) have been studied in cancer, compared with a group of healthy control. AGP has four genetic variants: AGP F1, F2, and S variants correspond to the ORM1 gene whereas AGP A corresponds to the ORM2 gene. The proportion of ORM1 and ORM2 variants were studied in plasma using a novel UPLC–MS method. Plasma total AGP level was 0.5 ± 0.2 g L−1 and the proportions of the ORM1 and ORM2 variants were 76.3 ± 8.2% and 23.7 ± 8.2%, respectively. In cancer plasma AGP levels increased fourfold and the proportion of ORM1 variants increased to 88.7 ± 6.8%. Changes in the proportion of genetic variants due to cancer were clearly significant, as shown by statistical analysis. Three different cancer types have been studied, lymphoma, melanoma, and ovarian cancer. The results did not show any difference depending on cancer type. The results indicate that, in accordance with prior expectations, the ORM1 variant is predominantly responsible for the acute-phase property of AGP.  相似文献   

18.
蒋晔  张嫡群 《分析化学》1992,20(7):822-824
本文使用重叠分辨图谱(ORM)法预示了HPLC分离二氢吡啶类药物和肺保三效片中组分的最佳流动相组成。实验表明ORM法是一种迅速、多用途的优化方法。  相似文献   

19.
Orosomucoid (ORM) polymorphism was investigated by different methods including isoelectric focusing in acid pH ranges followed by silver staining, print immunofixation of desialyzed ORM, fixation using a lectin from the sea-weed Codium tomentosum, isoelectric focusing followed by immunofixation in miniaturized gels and isoelectric focusing in immobilized pH gradients. Population genetics studies were carried out in Galicia (NW Spain) and two new ORM variants were found.  相似文献   

20.
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