Characterization of overlapped chromatographic peaks by the second derivative. The limit of the method

1990 ◽  
Vol 62 (7) ◽  
pp. 717-721 ◽  
Author(s):  
Eli. Grushka ◽  
Dror. Israeli
Keyword(s):  
Second Derivative ◽  
Chromatographic Peaks

scholarly journals Width Based Characterization of Chromatographic Peaks: Beyond Height and Area

2017 ◽  
Vol 89 (7) ◽  
pp. 3893-3900 ◽  
Author(s):  
Akinde F. Kadjo ◽  
Hongzhu Liao ◽  
Purnendu K. Dasgupta ◽  
Karsten G. Kraiczek
Keyword(s):  
Chromatographic Peaks

Isolation and preliminary characterization of a fraction of bilirubin in serum that is firmly bound to protein.

1982 ◽  
Vol 28 (4) ◽  
pp. 629-637 ◽  
Author(s):  
J J Lauff ◽  
M E Kasper ◽  
T W Wu ◽  
R T Ambrose
Keyword(s):  
Azo Dyes ◽  
Diazonium Salt ◽  
Visible Spectrum ◽  
Strong Acid ◽  
The Other ◽  
Direct Reaction ◽  
Fraction Absorbed ◽  
Chromatographic Peaks ◽  
Liquid Chromatographic

Abstract We have isolated from pathological sera a bilirubin fraction (delta) that is very tightly, if not covalently, bound to protein, most likely albumin. This delta fraction absorbed at a lambda max of 433 nm in the visible spectrum, between the lambda max of unconjugated (alpha) and that of conjugated (Bc) bilirubin when measured in solutions containing albumin. However, unlike the other bilirubin species, this fraction could not be separated from the proteins in serum by exhaustive ultrafiltration in the presence of caffeine/benzoate solution. In the Jendrassik-Grof diazo procedure for bilirubin analysis, the delta fraction gave a large direct reaction (76-89% of the total reaction). Yet, when relatively hydrophobic azo dyes were formed by reaction of the delta fraction with the diazonium salt of dichloroaniline, only 50% of the dyes were extractable from aqueous solution. On chromatography the rest remained associated with protein. Of the extractable dye, more than 70% was accounted for by two liquid-chromatographic peaks with retentions identical with those of azo dyes formed from unconjugated bilirubin. This delta fraction was not appreciably separated from protein by treatment with strong acid or base, or by prolonged digestion with various enzymes. Finally, in a highly denaturing solvent (urea/mercaptoethanol), this fraction was not dialyzable through a membrane with a 12 000-dalton cutoff.

scholarly journals Yet another characterization of the sine function

1981 ◽  
Vol 4 (2) ◽  
pp. 371-381
Author(s):  
Robert Gervais ◽  
Lee A. Rubel
Keyword(s):  
Entire Function ◽  
Complex Plane ◽  
Exponential Type ◽  
Second Derivative ◽  
Sine Function ◽  
Number Of Zeros ◽  
Expository Paper

In this expository paper, it is shown that if an entire function of exponential type vanishes at least once in the complex plane and if it has exactly the same number of zeros (counting multiplicities) as its second derivative, then this function must take the formAsin(Bz+C).

Computer characterization of chromatographic peaks by plate height and higher central moments

1969 ◽  
Vol 41 (7) ◽  
pp. 889-892 ◽  
Author(s):  
Elimelech. Grushka ◽  
Marcus N. Myers ◽  
Paul D. Schettler ◽  
J. Calvin. Giddings
Keyword(s):  
Plate Height ◽  
Central Moments ◽  
Chromatographic Peaks

Characterization of Magnetic Particles Using a Wavelet Function

2009 ◽  
Vol 68 ◽  
pp. 175-182
Author(s):  
Humberto J. Ochoa Domínguez ◽  
Perla E. Garcia Casillas ◽  
Carlos A. Martínez Pérez ◽  
José Trinidad Elizalde Galindo ◽  
Hector Camacho Montes ◽  
...  
Keyword(s):  
Magnetic Particles ◽  
Diffuse Reflectance ◽  
Crystal Size ◽  
Diffuse Reflectance Spectroscopy ◽  
Wavelet Function ◽  
Second Derivative ◽  
Visible Spectroscopy ◽  
Absorption Bands ◽  
Reflected Light

The second derivative of the remission function of several magnetic materials is calculated for the parameterization of the position and intensity of the absorption bands of diffuse reflectance spectroscopy. The reflectance spectra are obtained by ultraviolet-visible spectroscopy (UV-VIS) from 400 to 1100 nm at increments of 1nm. The noise of the remission function results on errors after calculating the second derivative. Therefore, filtering of the remission function is needed before taking any action on this signal. Several methods are tested in order to calculate the second derivative. The best polynomial resulted on a second order wavelet function which is applied to the filtered remission function. Light scattering Mie theory is used to prove the behaviour of the reflected light. This research provides a method to identify and quantify magnetic particles, as well as the crystal size.

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