HC1 extraction

Tributyltin oxide and its metabolites were determined in urine after conversion to chlorides with HC1, extraction with ether containing tropolone (1), conversion to hydrides with NaBFLt, extraction with hexane and GC-AAS end-analysis LOD 1 pg/L for BuSnFL and Bu2SnH2, and 2 pg/L for Bu3SnH87b. 

Add 20g (0.08M) (VI) to 3 8% HBr in glacial acetic acid and stir and reflux for 6 hours. Pour onto ice and water, neutralize with solid sodium carbonate and extract with ether. Extract the ether with 10% aqueous NaOH, acidify the aqueous solution with HC1, extract with ether and dry, evaporate in vacuum (can distill) to get 2-(3,5-dihydroxyphenyl)-3-methyloctane (VII) (5-(l,2-dimethylheptyl)-res-orcinol). 

Uri ne Hydrolyze with HC1 extract with isopropyl ether remove sol vent dissolve residue in water add P- cycl odextri n HPLC/UV 1 ppm 97-102 Yoshi kawa et al. 1986 o, m, p... 

It may be expected that both HC1 extraction and NH4NO3 exchange might increase the effective diffusivity by removing residual exchangeable cations, notably sodium, that partially block the crystalline channels. Since sodium typically poisons cracking sites, its removal should also have a beneficial chemical effect. 

Dilute the amniotic fluid, 5 cm3, with an equal volume of water. To this add 10 cm3 of saturated (NH JjSO solution, and adjust the pH to 1.0 with concentrated HC1. Extract this mixture... 

To a solution of l,l,2,2-tetrafluoro-3-(tosyloxy)propane (0.86 g, 3 mmol) in THF was added dropwise 1.6M BuLi in hexane (4.1 mL, 6.6 mmol) at — 78°C over 20 min under argon. After lOmin at — 78 "C, the reaction was quenched with cold 10% aq HC1. Extraction, drying, concentration, and column chromatography (benzene) give a pale-yellow syrup yield (70%) (E/Z) 14 86. The procedure can also be applied to a 15-mmol scale. 

Cheese, yogurt, Water extraction, centrifuga- 55 chocolate, fish, tion, HC1 extraction, cen-... 

Extraction with a mixture of CH2C12, ethylacetate, MeOH, and NH4OH. Decantation, filtration, evaporation to dryness. Ether-MeOH dissolution, HC1 extraction. Acid layers washed with hexane, basified, LLE in CH2C12. Organic extract evaporated, dissolved in MeOH, and filtered. 

Weigh the sample and identify the styphnate by decompg a portion of it with aq HC1, extracting the free styphnic acid formed with etherjevapg the ether.and recrystallizing the... 

Sripriya, G., Antony, U., and Chandra, T. S. (1997). Changes in carbohydrate, free amino acids, organic acids, phytate and HC1 extractability of minerals during germination and fermentation of finger millet (Eleusine coracana). Food Chem. 58,345-350. 

Antimony in HC1 extract may also be measured by atomic absorption or ICP emission spectrometry. 

In all work reported herein, product mixtures were obtained by swamping alcoholic solutions with dil. HC1, extraction with methylene chloride and the extract washed with dilute KOH. Product ratios did not change under reaction or workup conditions. 

An appropriate portion of the HC1 extract of the concrete sample is prepared for analysis of the sample for lewisite 1, lewisite 2, and lewisite oxide (Figure 4, fraction 3B). The pH of the sample is adjusted with hydrochloric acid to pH 2, the sample is filtered, and 0.1 ml of a freshly prepared solution containing DMT 5 mg ml-1 in acetone is added. The sample vial is shaken vigorously and then allowed to stand for 10 min. After addition of 1 ml of n-hexane, the sample is shaken vigorously for 30 s every 10 min for 30 min. The hexane fraction is allowed to separate. The top hexane-water layer is transferred to a new vial and centrifuged. After centrifugation, the hexane fraction is separated, dried, and submitted for analysis. 

HC1 Treating. The 1000°F— distillate fractions of the filtered liquid products from Experiments 3, 4, and 6 in Table V, upon saturation at ambient temperature and pressure with dry HC1 gas, formed small amounts of dense, black liquid precipitates in each case (Table VII). A selective precipitation of nitrogen compounds took place as evidenced by the reduced nitrogen content in the raffinate phases and the increased nitrogen levels in the HC1 extract phases. Of the nitrogen originally present in the distillate samples, the bulk remained in the raffinates, while minor proportions appeared in the extract phases and as water-soluble material. The possibility that solubility of the amine hydrochloride in the... 

In Table IX the effects of reducing catalyst particle size from 8-20 mesh to 100-270 mesh powder are evident. In Experiment 10, Scheme B produced significantly less HC1 extract than was found using twice as much 8-20 mesh granular catalyst in Experiment 6 of Table VIII. Also... 

The weight percents of coal converted to hexane insolubles in Scheme C and to HC1 precipitates in Schemes A and B are listed in Tables VIII and IX. The extract values given for Schemes A and B have been corrected for the HC1 extract found in the liquefaction solvent. Elemental analyses of various extract and raffinate phases produced by applying Schemes A, B, and C in Table VIII are presented in Table X. 

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