Silanization Silica

Analysis of neutral product for active species. The di- and poly sulfonates present in AOS have been isolated from monosulfonates by column chromatography using silanized silica gel by Puschmann [109]. The content of mono-and disulfonates in the fractions obtained were determined gravimetrically. [Pg.435]

In PLC, polar adsorbents (silica and alumina) and nonaqueous solvents of low viscosity are usually used. Chemically bonded adsorbents (silanized silica) are poorly wettable by aqueous mobile phases and are relatively expensive, thus they are not often applicable [3]. [Pg.66]

FIGURE 11.11 (a) Schematic representation of PLC of Heracleum sosnowskyi fruit crude extract, system silanized silica/MeOH + HjO (6 4) (b) rechromatography of fractions I and II from the plate a on Lobar-type column filled with Horisil eluted with 5% MeCN in CHjClj -I- H (7 3) fractions controlled by analytical HPLC in system ClS/MeOH -i- HjO (6 4). For abbreviations, see Figure 11.5. (For details, see Waksmundzka-Hajnos, M. and Wawrzynow-icz, T., /. Planar Chromatogr, 3, 439 141, 1990.)... [Pg.273]

A TLC method for determination of quaternary ammonium antiseptics was proposed, using silanized silica plates in combination with triiodide ions and UVV densitometry at 400 nm. The method was applied to cetylpyridinium chloride, cetrimide (197c) and the isomers of benzalkonium chloride (197b)420. [Pg.1118]

Benzoates TBA Silanized silica PeOH + phosphate buffer 65... [Pg.76]

Octyl silane and butyl silane silica gels... [Pg.247]

Silica gel 60 F2S4, alumina 60 F2S4 E silanized silica gel GF254 Cyclohexane-boizene-diethylamine. Cydohexane cetone-diethylainine. methanol-aqueous 2S% ammonia for silica gel. Benzene-acetone for alumina Acetone-water-aq. 25% NH3 for silanized silica gel. 51... [Pg.122]

Sample codes SU S-SBR reinforced with untreated silica SPA S-SBR with PA-silica SPPy S-SBR with PPy-silica SPTh S-SBR with PTh-silica ST S-SBR with silanized silica... [Pg.197]

Sample codes SEU SBR/EDPM reinforced with untreated silica SEPA SBR/EDPM with PA-silica SEPPy SBR/EDPM with PPy-silica SEPTh SBR/EDPM with PTh-silica SET SBR/EDPM with silanized silica... [Pg.203]

The chromatographic behavior of 4//-pyrido[ 1,2-a]pyrimidin-4-ones and their 6,7,8,9-tetrahydro derivatives was studied on silanized silica gel layers using a aqueous mobile phases by TLC in normal chambers, and by OPTLC in a pressurized ultramicrochamber (88MI1-88MI3 89MI10 90MI1). [Pg.107]

Figure 11.5 Dependence of friction on load for a single microcontact. The friction force between a silica sphere of 5 //in diameter and an oxidized silicon wafer is shown (filled symbols). Different symbols correspond to different silica particles. The solid line is a fitted friction force using a constant shear strength and the JKR model to calculate the true contact area (based on Eq. (6.68)). Results obtained with five different silanized particles (using hexamethylsililazane) on silanized silica are shown as open symbols. Redrawn after Ref. [467].

TLC was carried out on various types of plates silica gel, silanized silica gel, cellulose and alumina, as well as in several different solvent systems benzene, chloroform, cyclohexane, benzene/acetone (90 10), cyclohexane/ethyl acetate (95 5), cyclo-hexane/acetone/triethylamine (70 25 5), hexane/benzene (60 40) and hexane/ether (80 20). Spots were either visualized by ultraviolet or developed by pulverization of a 1% blue B salt aqueous solution. [Pg.216]

Tests using unlabeled DANS-A9-THC showed that the main difficulty encountered was hydrolysis of the ester-phenol bond on the chromatographic plate. The most satisfactory separations were obtained in the dark on silanized silica gel plates. Under these conditions, DANS A9-THC remained stable throughout chromatography. [Pg.216]

Chromatographic System (See Chromatography, Appendix IIA.) Use a suitable high-performance liquid chromatograph equipped with a detector measuring at 210 nm and a 250- x 4.6-mm (id) column packed with octadecyl silanized silica (10-p.m Partisil ODS-3, or equivalent), and operated under isocratic conditions at 40°. The flow rate of the Mobile Phase is about 2 mL/min. [Pg.38]

Nucleosides (4) silanized silica gel-60 Reversed micelles of sodium dioctylsulfo-succinate in cyclohexane TLC 87... [Pg.30]

For reversed-phase adsorbents such as charcoal or completely silanized silica, this eluotropic solvent series is valid in the reverse order. In this case, the eluting power increases in the following sequence water < methanol < ethanol < acetone < 1-propanol < 1-butanol diethyl ether ethyl acetate < benzene < n-hexane". ... [Pg.495]

Amino add and symbol SiUca gel G (A) Micro- crystalline cellulose (B) Fixion 50-X8 (NaA (C) Silanized silica gel +4% HDBS (D) pi... [Pg.129]

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