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431.
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系数倍率导数光谱法定量测定纤维上染料 总被引:1,自引:0,他引:1
本文介绍了用系数倍率导数光谱法同时测定黄棕色涤纶上的分散黄RGFL,分散棕2RL,分散红S-BWFL的配比。这三种染料吸收峰重叠大,用该法可以完全消除彼此的干扰而不用分离,测得三种染料的配比与工艺配方中的比例一致,结果准确,可靠,回收率较好。这个方法操作简便,快速,可用于纵上染料的测定。 相似文献
433.
将Kalman滤波用于常规荧光、同步荧光、导数荧光、吸收光谱及导数光谱,实现了不经分离对苯酚与间苯二酚混合物及复方药物制剂的同时测定。结果良好,操作简便。 相似文献
434.
探讨了我率导数光谱(d^nT/dλ^n)与吸光度导数光谱(d^nA/dλ^n)的关系,并讨论了用d^nT/dλ^n作定量分析的可行性及其产生分析误差的原因以及最佳测量条件。 相似文献
435.
Two spectrophotometric methods are described and applied to resolve ternary mixtures of the corticosteroid hydrocortisone (HYD) and the antibiotics nystatin (NYS) and oxytetracycline (OXY). The simultaneous determination of these three compounds was firstly accomplished by a derivative method using the “ratio spectrum-zero crossing derivative” and then by multivariate methods partial least squares (PLS)-1, -2 and principal component regression (PCR). Multivariate calibration methods provide, specially PLS-2 in this case, a clear example of the high resolving powder of these techniques. The two described procedures do not require any separation step. Repeatability and reproducibility studies were achieved over two series of 10 standards for each compound showing no significant differences at 95% confidence level in the four spectrophotometric methods. A comparison of the derivative and multivariate calibration results obtained in pharmaceutical formulations was performed resulting in agreement of the values obtained and the results was confirm by a high-pressure liquid chromatography (HPLC) method. 相似文献
436.
Mahmure Ü. Özgür Güzin Alpdoğan Bürge Aşçi 《Monatshefte für Chemie / Chemical Monthly》2002,133(2):219-223
Summary. A simple and rapid derivative spectrophotometric assay procedure is described for the analysis of caffeine (1), acetaminophen (2), and propyphenazone (3) in tablet formulations. The concentration range of application is 5.0–25.0 μg·cm−3 for 2 and 3 and 1.0–5.0 μg·cm−3 for 1. The method involves the extraction of the drugs from tablets with 0.1 N H2SO4, filtration, appropriate dilution, and measurement of the fourth derivative absorbance values at zero crossing wavelengths
of 230.0, 263.2, and 256.6 nm for 1, 2, and 3. As a reference method, a reversed phase HPLC procedure was developed. Commercially available tablets were analyzed; statistical
comparison of the results with those obtained from the reference method showed good agreement. The derivative spectrophotometric
method has the advantage of being simple, rapid, inexpensive, and easy to perform.
Received April 18, 2001. Accepted (revised) June 5, 2001 相似文献
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Abedallah Rababah Mohammed Al-Refai 《Numerical Functional Analysis & Optimization》2013,34(5-6):660-673
In this paper, we give a new, simple, and efficient method for evaluating the pth derivative of the Jacobi polynomial of degree n. The Jacobi polynomial is written in terms of the Bernstein basis, and then the pth derivative is obtained. The results are given in terms of both Bernstein basis of degree n ? p and Jacobi basis form of degree n ? p and presented in a matrix form. Numerical examples and comparisons with other well-known methods are presented. 相似文献