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  • 1
    Electronic Resource
    Electronic Resource
    Liquid chromatography on carbosilochrom and carbosilica gel-silica adsorbents with a modified carbon surface (1978)
    Springer
    Chromatographia 11 (1978), S. 206-211 
    Details
    ISSN: 1612-1112
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The silica adsorbent Silochrom C-120 which is homogeneous, macroporous and thermally stable, and Spherisorb S20W which is a wide-pore silica gel have been modified by the deposition on them of carbon formed by the pyrolysis of benzene. The adsorbent structures before and after modification have been studied. Columns packed with the Carbosilochrom and Carbosilica gel so obtained were used for studies of their selectivity in the liquid chromatography of an homologous series of polymethyl-and monoalkylsubstituted benzenes, alkylnaphthalenes, methylphenols and benzoic esters on elution with solutions of methanol + water of different concentrations. An increase in the amount of carbon deposited on the adsorbent and an increase in solvent polarity results in an increase in adsorbent selectivity. In the case of polymethylsubstituted benzenes this increase is greater than in the case of isomeric monoalkylsubstituted benzenes. For phenols this increase is less than that for the corresponding hydrocarbons. The separating power of the column can be controlled by changing the degree of specificity of the carbosilica and the polarity of the eluent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02302394
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  • 2
    Electronic Resource
    Electronic Resource
    Molecular parameters and retention characteristics of unsubstituted polyaromatic hydrocarbons in HPLC (1988)
    Springer
    Chromatographia 25 (1988), S. 272-278 
    Details
    ISSN: 1612-1112
    Keywords: Column liquid chromatography ; Polyaromatic hydrocarbons ; Molecular parameters ; Retention prediction
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The present research studies the possibility of using the correlation dependence between molecular parameters of unsubstituted polyaromatic hydrocarbons (PAH) and their retention in reversed-phase liquid chromatography to optimize the conditions for the separation and identification of unknown peaks on the chromatograms of multicomponent mixtures. A linear correlation equation, that takes the number and environment of the carbon atom in the PAH molecule into account as well as the differences in the specific interactions of isomeric molecules with polar eluent, has been proposed. The adequacy of the proposed PAH retention model was verified by comparing the calculated retention values with the experimental data. The possibility of identifying unsubstituted PAH according to the number of carbon atoms of various types and according to the values of the molecules lengths (calculated on the basis of the retention of these substances under different eluent compositions) was exemplified by various chromatographic systems (reversed phase-eluent-PAH molecules).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02324700
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  • 3
    Electronic Resource
    Electronic Resource
    The effect of the structure of bonded cyanoalkyl stationary phases on their selectivity in the liquid chromatographic separation of polynuclear aromatic hydrocarbons (1989)
    Springer
    Chromatographia 27 (1989), S. 147-155 
    Details
    ISSN: 1612-1112
    Keywords: High-performance liquid chromatography ; Cyano-silica stationary phases ; Polycyclic aromatic compounds ; Relationship between retention and molecular structure ; Retention mechanism
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The paper discusses the effect of the length and structure of the hydrocarbon chain connecting the nitrile group to the silica gel surface on the chromatographic properties of cyanoalkyl phases. When using non-polar and polar mobile phases, the selectivity of the cyanodecyl phases toward PAHs is higher than of the cyanopropyl phase and of hydroxylated silica gel. Polar additives to the mobile phase drastically decrease the retention on silica gel and on the cyanopropyl phase while affect the properties of cyanodecyl phases only to a considerably less degree. Newly synthesized phases with different structures of the hydrocarbon chain are compared with the commerical cyano-and ODS-phases. The retention mechanism on the cyanoalkyl phases is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02265867
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  • 4
    Electronic Resource
    Electronic Resource
    Regularities in the retention of nonsubstituted polynuclear aromatic hydrocarbons in liquid chromatography on polar adsorbents (1985)
    Springer
    Chromatographia 20 (1985), S. 533-537 
    Details
    ISSN: 1612-1112
    Keywords: Liquid chromatography ; Polyaromatic hydrocarbons ; Polar stationary phase ; Relationship between retention and molecular structure
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The retention of polynuclear aromatic hydrocarbons (PAH) is studied in liquid chromatography, using columns packed with silica gel with a hydroxylated surface and the same silica gel with surface-bonded amine and nitrile groups. A linear relationship was found between retention and the number of π-electrons in the molecule, the size of the molecule and the different types of carbon atoms in the molecule. The different carbon atoms in a PAH molecule contribute differently to the retention and this contribution depends on the nature of the polar functional groups on the adsorbent's surface and on the nature and concentration of a polar modifier present in a non-polar eluent.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02312172
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  • 5
    Electronic Resource
    Electronic Resource
    Binding of lipoproten complexes of cholesterol to siliceous matrices (1987)
    Springer
    Pharmaceutical chemistry journal 21 (1987), S. 270-274 
    Details
    ISSN: 1573-9031
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00767396
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  • 6
    Electronic Resource
    Electronic Resource
    Gas chromatography of low molecular weight halocarbons on macroporous silica modified by a thin liquid phase film (1986)
    Springer
    Chromatographia 21 (1986), S. 681-686 
    Details
    ISSN: 1612-1112
    Keywords: Gas chromatography ; Macroporous silica ; Silica-adsorbent modification ; Low boiling halocarbons ; Analysis of water pollutants
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The use of the silica adsorbent Silochrom C-80 modified by a thin liquid stationary phase film is proposed for the gas chromatographic analysis of low molecular weight halocarbons. Such modified adsorbents are characterized by good retention of the volatile halocarbons and high selectivity with respect to halocarbons. The thermodynamic sorption characteristics of alkanes, chloroalkanes and chloromethanes on Silochrom modified by three liquid phases (Apiezon L, methylsilicone and polyethylene glycol 20M) and on Chromaton N with thick films of the same phases were studied. The heats of sorption (−ΔH) and free sorption energy changes (−ΔF) of these substances and the increments −Δ(ΔH) and −Δ(ΔF) per chlorine atom in the chloralkane molecule compared with n-alkanes with the same number of carbon atoms were determined. The “chlorine” retention indices of low molecular weight volatile halocarbons on three sorbents were determined to identify them in aqueous solutions using the electron-capture detector. The analysis of drinking water by this technique is demonstrated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02313679
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  • 7
    Electronic Resource
    Electronic Resource
    Chromatography of proteins and viruses on macroporous silica modified with carbohydrates (1984)
    Springer
    Chromatographia 18 (1984), S. 69-72 
    Details
    ISSN: 1612-1112
    Keywords: Liquid column chromatography ; Proteins ; Viruses ; Macroporous silica ; Surface chemical modification
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary The adsorption and the chromatography of proteins and viruses on macroporoussilicas have been studied. Modification of the silica surfaces with γ-aminopropyltriethoxysilane and then with carbohydrates has eliminated the irreversible adsorption of these biopolymers. The chromatographic separation of the biopolymers has revealed molecular sieve (size exclusion) effects and reversible adsorption. The influence of pH on the elution of proteins and viruses has been demonstrated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02268459
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  • 8
    Electronic Resource
    Electronic Resource
    Macroporous silica as an adsorbent for molecular chromatography (1971)
    Springer
    Chromatographia 4 (1971), S. 93-97 
    Details
    ISSN: 1612-1112
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Ein makroporöses Siliziumdioxid (Silochrom C80) mit einer spezifischen Oberfläche von ungefähr 80 m2/g und einem Porendurchmesser von etwa 550 Å wird zur Verwendung in der Gas-Adsorptions-Chromatographie vorgeschlagen. Silochrom C80 ist durch eine große geometrische Homogenität charakterisiert. Silochrom mit einer hydroxylierten Oberfläche ist ein spezifisches Adsorbens. Die spezifische Wechselwirkung des Silochroms mit den Molekeln der Gruppe B und D führt zur Bildung von Wasserstoffbrücken. Gesättigte und aromatische Kohlenwasserstoffe, Äther und Ester, Acetophenon, Nitrobenzol und Anilin werden aus der chromatographischen Säule mit Silochrom C80 bei Temperaturen von 100–200°C als symmetrische Peaks eluiert.
    Abstract: Résumé Une silice macroporeuse (Silochrom C80) de surface spécifique de 80 m2/g environ et de pores de diamètre d'environ 550 Å est proposée pour la chromatographie d'adsorption gaz-solide. Le Silochrom C80 est caractérisé par une haute homogénéité de surface. Ce Silochrom dont la surface est hydroxylée est un adsorbant spécifique. L'interaction spécifique du Silochrom avec les molécules des groupes B et D consiste en la formation de liaisons hydrogène. Les hydrocarbures saturés et aromatiques, les éthers et esters, acétophénone, nitrobenzène et aniline sont élués de la colonne chromatographique de Silochrom C80 sous forme de pics symétriques à des températures comprises entre 100 et 200°C.
    Notes: Summary Macroporous silica, Silochrom C80, with a specific surface area of about 80 m2/g and pore diameter of about 550 Å is suggested for use in gas-adsorption chromatography. Silochrom C80 is characterized by high geometrical surface homogeneity. Silochrom, which has a hydroxylated surface, is a specific adsorbent. The specific interaction of Silochrom with molecules of groups B and D consist in reversible formation of hydrogen bonds. Saturated and aromatic hydrocarbons, ethers, esters, aldehydes, alcohols, acetophenone, nitrobenzene and aniline energe rapidly from a chromatographic column of Silochrom C80 at temperatures 100–200°C with symmetrical peaks.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02311195
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  • 9
    Electronic Resource
    Electronic Resource
    Adsorption and chromatography of proteins on chemically modified macroporous silica-aminosilochrom (1973)
    Springer
    Chromatographia 6 (1973), S. 187-189 
    Details
    ISSN: 1612-1112
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Adsorption and chromatography of several proteins on macroporous silica — Silochrom was investigated. Chemical modification of the Silochrom surface by means of γ-aminopropyltriethoxysilane eliminates irreversible protein adsorption. The effect of salt concentration and pH of eluent on protein elution volumes from “aminosilochrom” columns is discussed. It is possible to use the aminosilochrom for chromatographic separation of proteins.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02269191
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  • 10
    Electronic Resource
    Electronic Resource
    Aerosil on a carrier as a sorbent for gas cheomatography (1969)
    Springer
    Russian chemical bulletin 18 (1969), S. 1287-1289 
    Details
    ISSN: 1573-9171
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Conclusions 1. The Chromatographic properties of an adsorbent prepared by applying aerosil on Chromosorb and the corresponding volume-porous adsorbent (aerosilogel) were compared, 2. The use of a surface-layer adsorbent increased the efficiency of Chromatographic columns, expands the region of compounds that can be analyzed at a given temperature, and reduces the time of analysts.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00908195
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