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Страница 85.

Most of the latter was removed by distillation. The acid was removed by addition of a few ml. of 0. 5% methanolichydrogen chloride, followed by distillation with repeated additions of methanol. The final polymer was readily hydrolysed by distillation with water. Most studies of the kinetics of reactions involving two proton transfers have been made indirectly, e. g. , by racemisation, isotope exchange, or halogenation. This assignment of structure was supported by cleavage of the substance by the boron trifluoride-ether complex to material shown by its ultraviolet absorption spectrum to contain a lOb, 11-double bond. The [most likely explanation for the
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increased entropies is provided by built-in salvation,'» suggested by Bun-nett and Morath. The yields of major products formed by pyrolysis of n-octyl nitrate at 116° and 132° are shown in the Table. Concentrations of oligosaccharide solutions were measured by acid hydrolysis to glucose, unless otherwise stated. The solvent was removed from the dried ethereal extract to leave a thick brown oil (3,8 g. ), which was purified by repeated sublimation at 100—120°/0,5 mm, affording colourless prisms, m. p. 84—86°, identical with the product of the previous experiment.
4,5,5-Trimethyl-l-pyrroline (2 g. ) was converted into its hydro-chloride by treatment with the equivalent amount of concentrated hydrochloric acid. The isomaltose component was removed by chro-matography on thick paper to give chromatographically pure material. The mixture of sugars was separated by chromatography on thick filter paper into glucose. The compound was shown by infrared spectra to be identical with the trans-anti-ketone. This was confirmed by infrared spectroscopy.
§ 137. После предлога by дополнение часто выражается инговой формой (герундий, см. § 103).
Например:
The hydrochloride of the di-iodo-compound is very sparingly soluble in boiling 2N-hydro-chloric acid, and traces of 3'-iodo-L-thyronine are easily removed from 3',5'-di-iodo-L-thyronine by treatment with hydrochloric acid. З'-iodo-L-thyronine was conven-tiently prepared by treating thyronine with an excess of iodine and removing the di-ido-thyronine as its hydrochloride.
Slow linear sweep of the field for phase-sensitive detection was obtained by feeding the output from a Miller sweep generator into the control amplifier of the power unit. The purity of the stable isotopes was established by analysing the solutions of the dissolved metal beads, but only limited quantities could be spared for the analysis and the limits of impurity given in Table 2 reflect this. After the solution had been kept for 17 hr. , the acid was removed by stirring in barium carbonate, and the precipitate was removed in a centrifuge. Identification of this material was confirmed by comparing its infrared spectrum with that of authentic material.
Potassium hydrogen di-iodate (bi-iodate) was obtained by crystallising equimolar quantities of the constituents from hot water, and deuteroiodic acid from a solution of iodine pentoxide (dried for several days at 200—210") in deuterium oxide.
Anhydrous nickel iodate was prepared by heating together nickel nitrate and iodic acid in 8N-nitric acid, and ferric iodate by adding ferric nitrate in 4N-nitric acid to boiling aqueous iodic acid.
Potassium hexaiodatomanganate (IV) was obtained by boiling together freshly precipitated manganese dioxide, iodic acid, and potassium iodate, according to Berg's method.
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The alkaloids, recovered by extraction with chloroform (4x 300 с. с. ), were converted into their hydrochlorides by dissolving them in methanol (150 с. с. ), adding concentrated hydrochloric acid (20 с. с. ), and precipitating the salts with ether.
§ 138. Когда процессы выражаются не существительными, а глаголами в личной форме страдательного залога [например, is (are, was, were) oxidised, а не oxidation, oxidising; is (are, was, were) treated, а не treatment, treating, вещества, которые используются для осуществления этих процессов, часто вводятся предлогом with.

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