Amberlite alkaline

Kasuganobiosamine (4) and Kasugamycinic Acid (9a) by cold Alkaline Hydrolysis. Kasugamycin hydrochloride (622 mg., 1.43 mmoles) was dissolved in 5 ml. of water free from carbon dioxide and 50 ml. of water saturated with barium hydroxide was added. The solution was allowed to stand at room temperature for 36 hours. Ammonia (0.30 mmole) was produced and barium oxalate (199 mg., 0.80 mmole) was obtained. After removal of barium oxalate by filtering, the filtrate was neutralized with dry ice. After removal of barium carbonate by filtering, the filtrate was adjusted to pH 7.0 and placed on a column of Amberlite CG-50 (ammonium form, 1.5 x 22 cm.), allowed to pass with a rate of... 

Kiss [8] examined various techniques for the efficient separation and preconcentration of boron from marine sediments. Alkaline fusion with potassium carbonate was used to render boron reactive, even in the most resistant silicate minerals. Fusion cakes were extracted with water and borate was isolated by Amberlite XE-243 boron-selective resin. Borate was determined spectrophotometrically, following elution with 2 mol L 1 hydrochloric acid. Either the carminic acid complex (620nm), formed in sulphuric acid (94%) or sulphuric acetic acid (1 4), or the azomethine hydrogen ion association complex (415nm) formed at pH5.2, were used for borate measurement. 

An anion exchange resin (e.g. Amberlite R-120) was treated with protonated dithiooxamine, H2NC(S)C(S)NH2 Using the supported ligand, quantitative removal of copper, cadmium, and lead ion solutions at neutral or slightly alkaline solutions of deionized or tap water, but poor results were obtained with sea water [22]. 

DOM is derived from autochthonous sources such as phytoplankton and photosynthetic bacteria (16) at Big Soda Lake near Fallon, Nevada. This lake is alkaline (pH 9.7) and chemically stratified. It contains DOC concentrations as high as 60 mg/L and dissolved salt concentrations as high as 88,000 mg/ L (17). The DOM in this lake is colorless. The fulvic acid fraction was isolated by adsorption chromatography (Amberlite XAD-8 resin) (18) and by zeo-trophic distillation of water from N,N-dimethylformamide (19). Average molecular model synthesis was achieved in a manner similar to that used for fulvic acid from the Suwannee River. The characterization data are presented in Table I and the structural model is presented in Structure 2. 

Broccoli Glycosides of Q, K, and IS Freeze-dried, extraction with H20, SPE with Amberlite and Sephadex, alkaline or acid hydrolysis C-18 H20-Me0H-formic acid HPLC/DAD/MSn/ ESI(-) 107... 

The product from Step 1 was dissolved in 5 ml methyl alcohol and the solution made alkaline by the addition of 1 M sodium methoxide. The solution stood 3 hours and was neutralized with Amberlite IR 120 exchange resin. The solvent was removed, the residue purified by column chromatography, and the product isolated. 

Catalysis of Lobry de Bruyn-Alberda van Ekenstein reactions by a strongly basic, ion-exchange resin [Amberlite IRA-400(OH)] has now been demonstrated. Duff has reported that alkaline impurities present in paper brought about such transformations of several sugars when paper chromatograms thereof were dried at 110°. 

In order to characterize and quantify aquatic HUS specifically, they must first of all be isolated. The method most widely used at present isr sorption with synthetic resins at a low pH followed by elution with alkaline solution (i.e. at a high pH). Mantoura and Riley used amberlite on a polystyrene base (XAD-2) whilst Thurman and Malcolm used polyacrylamide (XAD-8). The method used by Frimmel and Niedermann on numerous bodies of water is shown in the chart below. 

Amberlite resin prior to injection into a dilute sodium hydroxide mobile phase. This provides the alkaline environment suitable for pulsed amperometry, although if reversed-phase chromatography provides better resolution of the carbohydrates under study, postcolumn addition of hydroxide can be carried out. 

The mesh size of the Amberlite must be reduced by crushing in a mortar to obtain a suitable flow rate. The silica gel 60 H is ready for use. The column has to be pretreated by subsequent elution of degased methanol, methanol/water/ acetic acid (50 50 5, v/v), and water/acetic acid (100 5). An evaporated ethanol extract is dissolved in a small volume of 1% acetic acid and applied to the adsorbent column. Salts and other polar substances are washed from the column by 1 % acetic acid, whereas corrinoids are eluted with degased water/methanol/acetic acid (50 50 5). Recoveries of 90% to 98%, as reported for OH-Cbl, SOs-Cbl, and AdoCbl, are about 10% higher than achieved by phenol extraction. Elution of cobalamin from Amberlite XAD can also be carried out with alkaline solvents such as methanolic 1% ammonium hydroxide. Under these conditions OH-Cbl is strongly retained by silanized silica gel (60). 

As membrane material for their direct ammonia-oxygen fuel cells, Lan and Tao used a blend of the anion-exchange resin Amberlite IRA 400 (hydroxide form) and poly(vinyl alcohol). As cathode material, Mn02 deposited on carbon materials was used. In different cell versions the anodes were prepared from Pt-Ru-C and from chrom-decorated nanosized nickel (size about 6 nm). Experiments with such cells at room temperature showed maximal power densities in the range 12 to 16 mW/cm. In some cases the power densities for ammonia-fed cells were higher than those for hydrogen-fed cells. The authors note that the development of direct ammonia fuel cells with alkaline membranes and inexpensive catalysts is still at an early stage. 

For some time, we have devoted ourselves to the Urogastrone study. Indeed Urogastrone is a factor provided, as we already said, with gastric anti-ulcer, auitisecretory and anti-motor activity, and is extracted from the urines of three month pregnant women. The urine is passed on an active charcoal column where the active material is absorbed it is then eluted in an acid medium and precipitated by an acetone and ether mixture. After a second precipitation by ammonium sulphate in alkaline medium, the acid solution is chromatographed on Amberlite IRC-50, then eluted at alkaline pH. 

The alkaline degradation products were satisfactorily fractionated by stepwise elution chromatography on an Amberlite CG-50 column to yield four main peaks consisting as expected of acetylpeptides (Fig. VIII-2). The structure of each frag-... 

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