Некоторых английских существительных, характерных для научной и технической литературы 9 страница
The following compounds were pure commercial samples, or were prepared by standard metathetical reactions: lithium, sodium, potassium, rubidium caesium, ammonium, tetramethylammonium, silver, thallous, thorium, lead, mercurous, and mercuric iodates. The corresponding ammonium salt was prepared by a similar pro cedure. Potassium hexaiodatotitanate was prepared by a modifica tion of the literature method. Conversion of the acid (V; R = H) Into 2,3-benzoxanthone (XIV) was carried out by two routes. Thus the v (CH) absorption of ethyl propiolate shifts and broadens considerably as compared with the hexane spectrum, and this is supported by the observed shift in v (CO). Potassium borohydride (4 g.) was added to the solution of the periodate-oxidised polysaccharide and, after 3 days, excess of borohydride was destroyed by treatment with Amberlite resin IR-120(H+), the solution was concentrated, and the reduced periodate-oxidised polysaccharide (3.5 g.) was precipitated by the addition of acetone (3 vol.) by fractional distillation and collected over narrow ranges. In a trial experiment, a paper chromatogram of dextran degraded by acetolysis showed the expected result, that the «nigerose» component was now present in a much greater quantity than was formed by aqueous acid hydro lysis. 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 exchan ge, 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.
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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 cry stallising 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.
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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 исполь-зуются для осуществления этих процессов, часто вводятся предлогом with.
Например:
When 3-nitropurin or 2-hydroxy-3-nitroanthra-l,4,9,10—di-quinone is oxidised in methanol with lead dioxide or potassium permanganate 2-hydroxy-3-nitroacetyl-l,4-naphthaquinone (III) is formed directly.
After being stored overnight, the solutions were neutralized with acetic acid and evaporated. The products were only partly soluble in water, so the deacetylation was repeated to give material completely soluble in water. This was treated with Biodeminrolit resin and evaporated to a syrup.
(a) 3-Nitroalizarin. When 3-nitroalizarin was oxidised in methanol with lead dioxide the first relatively stable product was a methyl ether (I) of 3-nitropurpurin, which on hydrolysis with aqueous hydrobromic acid was converted into 3-nitropurpurin (I). Solvent was removed and the polymer was precipitated with 1 : 1 ether-cyc-lohexane (3 с. с.), then dissolved in water and neutralised with tri-butylamme. The trisaccharide (10 mg.) was reduced with sodium bo-rohydride (20 mg.) for 24 hr. When it was hydrolysed with 1,5 N — sulphuric acid for 6 hr. the glucose liberated amounted to 65% of that from an equivalent weight of unreduced trisaccharide. The acetates were extracted with chloroform (3 X 100 ml), and the combined extracts were washed with sodium hydrogen carbonate solution and water and then dried (Na2S04). In a trial experiment the dextran was hydrolysed with dilute sulphuric acid to degrees of conversion into glucose ranging from 20 to 51 %.
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Optical spectra were measured with a Gary recording spectropho-tometer. The column was eluted with water to remove glucose.
§ 139. Встречается также употребление предлогов with и by в тождественных контекстах, что, по-видимому, указывает на отсутствие сознательной дифференциации между орудием действия и непосредственным деятелем.
Например:
The acid polysaccharide (3g.) was hydrolysed by N-sulphuric acid (50 ml.) at 100° for 4 hr. Since chromatography showed several oligosaccharides, both neutral and acidic, the mixture was
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rehydro lysed with N-sulphuric acid (30 ml.) at 100° for 2 hr. In a similar reaction but with decomposition by water and ice, sulphur (0,7 g.) was obtained from the ethereal and thiolbenzoic acid from the aqueous layer. In a similar reaction decomposition with water afforded an unidentified oil from the ethereal layer and benzoic acid from the aqueous layer.
Thus 1 mol. of dibenzoyl disulphide with 3 mols. of phenylmag-nesium bromide or phenyl-lithium afforded triphenylrnethyl thi-olbenzoate after decomposition by acid. Decomposition with ammonium chloride in case of the magnesium compounds and with water in case of lithium compounds gave, as expected, the triarylmethanols.
2-Phenylethanol has been found to be oxidised by ammonium metavandate to benzaldehyde, benzoic acid, and formic acid under conditions in which (a) dehydration to styrene did not occur and (b) phenylacetic acid was not oxidised, whilst (c) benzyl alcohol was rapidly oxidised. This olefin is only slowly oxidisedby vanadium (V), a:id it cannot be the immediate precursor. Mild oxidation of either y-oxo-y-2-xanthenylbutyric acid (I) or its methyl ester by potassium permanganate in aqueous acetone yielded y-oxo-y-2-xanthonylbutyric acid (II; R=H) or its methyl ester respectively.
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Oxidation of the sugar with periodate gave 0,06 mol. of formaldehyde. Reduction of the sugar with potassium borohydride followed by oxidation with periodate gave 0.87 mol. of formaldehyde.
It may be emphasised that in dioxan solution no significant phosphorylation of 5'-hydroxyl groups by diphenyl phosphorochlo-ridate occurred under the conditions employed. The present paper deals with the chemical oxidation of 3-nitro-alizarin and -purpurin by lead dioxide and potassium permanganate in methanol containing some acetic acid; in the following paper we compare the course of this oxidation with the photochemical degradation. Oxidation of the sugar with sodium metaperiodate in the presence of sodium hydrogen carbonate gave 0.04 mol. of formaldehyde. Hydrolysis of the diketo-ester (II; R = Me) with 5% alcoholic potassium hydroxide gave the diketo-acid (II; R = H), but treatment with 10% aqueous sodium hydroxide led to a phenolic acid. When this procedure failed to provide crystalline sulphone, the mixture was decomposed by ice and dilute hydrochloric acid, and the ethylene dichloride layer was separated and dried after being washed successively with water, dilute sodium hydroxide solution, and water again.
In control experiment, treatment of e-galactan with N-sulphuric acid at room temperature for 30 min. afforded no detectable reducing sugars. However, Kulkarni and co-workers obtained mixtures of cis- and trans-3, 4-diols on reduction of dihydrofisetin and dihydro 4'-methoxy-6-methylflavonol by lithium aluminium hydride. Bognar and Rakosi found that the reduction of dihydroflavonol by hydrogen over a supported palladium catalyst gives the trans-3,4-diol in
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both solvents. Reduction of the derived methyl ester methyl glyco-sides with potassium horohydride, followed by hydrolysis, gave galactose only. Oxidation of the disaccharide with periodate gave only traces of formaldehyde, whereas oxidation of the acidic disaccharide alcohol (from reduction by borohydride) gave 0,85 mol. of formaldehyde, a result consistent only with the presence of a 1,5- or 1,6-linkage. Conversion into the methyl ester methyl glycosides, reduction with potassium borohydride, and hydrolysis gave arabirio-se and galactose (chromatography). Similar treatment of the disaccharide alcohol (from reduction by potassium borohydride) gave only arabinose. Aliquot (arabinose) were withdrawn at intervals, excess of periodate was destroyed by ethylene and the liberated acid was titrated with 0,015 N-sodium hydroxide. The ether was removed and replaced by xylene, and the solution heated at 90° overnight. In contrast to the rapid reaction of these anilides, the quinoxalines (VI a-d) and the pyrazine (VII) were all unchanged by concentrated sulphuric acid at room temperature. In pyridine solution the 5'-hydroxyl group was phosphorylated by P1P2-dibenzyl P1P2-diphenyl pyrophosphate, tetra-allyl pyrophosphate, and tetrabenzyl pyrophosphate in that order of reactivity. The normal wave-guide connected to the heat-break was warmed by a small heater, to prevent condensation of moisture.
§ 140. Нередко вместо предлогов by и with употребляется сочетание by means of.
Например:
The magnetic field was measured by means of a marginal oscillator proton resonance meter.
The second harmonic of the frequency of the resonance was measured by means of a T74 frequency meter, manufactured by Telemechanics Ltd.
The values of «g» were calculated directly, the microwave frequency being measured by means of a Philips wavemeter, type RP4290X.
Exinite and micrinite, which are richer and poorer respectively than vitrinite in hydrogen, differ in density and can be fracti-oned, though with difficulty, by means of liquids differing in specific gravity.
§ 141. Следует также отметить, что предлог by входит в состав некоторых глагольных сочетаний и отвечает на вопросы: кем? чем? (например: to be followed by, to be accompanied by, to be provided by, to be substituted by, to be affected by, и т. п.). Например:
То, что за раскрытием эпоксидного кольца не следует перемещение брома к алкоксидному кислороду, не является
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неожиданностью. «That opening of the epoxide ring is not followed by displacement of the bromine by the alkoxide oxygen is not surprising*.
Реакция сопровождалась бурным выделением тепла. «The reaction was accompanied by violent evolution of heat».
Водородные атомы СН2-групп замещаются углеводородной группой обычным способом. «The hydrogen atoms of the CH2 groups are substituted by the hydrocarbon group in a regular manner».
На результаты повлияло наличие примесей. «The results were affected by the presence of impurities».
На скорости и молекулярные веса влияет понижение температуры. «The rates and molecular weights are affected by lowering the temperature».
Еще примеры: The d. c. magnetic field was provided by an 8" pole piece magnet with a 2 1/2" gap. Power for the magnet was pro vided by a stabilised power supply. The magnet and power unit were manufactured by Newport Instruments Ltd.
§ 142. Употребление в одном предлож eja ии страдательного и действительного залога. В английской научной и технической литературе нередко можно встретить в одном предложении страдательный и действительный залог. Например:
Кислород берут прямо из цилиндра и он проходит через уменьшающий клапан цилиндра. «Oxygen is drawn directly from a cylinder and passes through the cylinder reducing valve».
Четыре стеклянные трубки длиной в 135 лш. входят в отверстия и на них насажены резиновые наконечники с маленьким отверстием в центре. «Four glass tubes 135 mm long, fit into the holes and are sealed writh rubber washers containing a small central hole».
Это соединение могло бы немедленно разложиться с образованием двух молекул этилена или его можно было бы разложить столкновением с молекулой этилена. «The compound might de compose immediately into two molecules of ethylene, or be decomposed by collision with an ethylene molecule».
Трисахаридную фракцию частично гидролизовали кислотой и она дала пять дисахаридных соединений. «The trisaccharide fraction was partly hydrolyzed with acid and gave rise to five disac-charide compounds».
CONTINUOUS TENSES
§ 143. Continuous Active. Нередко в разных языках для выражения одних и тех же смысловых значений употребляются разные средства. То, что в одном языке выражается грамматически, в другом языке передается лексически, отдельными словами, и наоборот. Выражение лексических отношений в
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одном языке грамматическими формами в другом языке можно назвать «грамматизацией лексики». Типичным примером грамма-тизации лексики служат Continuous Tenses, не имеющие грамматических параллелей в русском языке. Continuous Tenses выражаются формулой to be -(- инговая форма смыслового глагола в настоящем, прошедшем или будущем времени, в действительном (Active) и страдательном (Passive) залоге и употребляются тогда, когда упор делается не столько на само действие, сколько на время его протекания.
В научной и технической литературе формы Continuous в основном употребляются для указания на то, что действие происходит в настоящее время, сейчас, в данное время, или что один процесс протекает во время осуществления другого процесса. В первом случае время протекания иногда передается не только грамматической формулой to be + инговая форма, но, одновременно, и словами типа to day, presently, во втором случае указание на время следует из слов типа wbile, when, as.
Например:
Хотя этому методу в настоящее время уделяется большое внимание, его возможности и недостатки еще недостаточно изучены. «Although the method is receiving marked attention (to-day), its possibilities and limitations have not yet been sufficiently explored».
Сферические соединения становятся сейчас все более употребительными при конструировании стеклянного оборудования. «The spherical joint is becoming more and more useful in the construction of glass equipment».
В настоящее время отсутствует убедительное доказательство этого эффекта. «Definite proof to that effect is (presently) lacking».
Раньше думали, что у бактерии полностью отсутствуют половые признаки, но сейчас появляется все больше данных о том, что они могут вступать в некоторого рода половое общение. «It used to be thought that bacteria were entirely without sex, but evidence is mounting up that they may undergo some kind of sexual process».
Вероятно, возможно получить большое число данных, которые в настоящее время отсутствуют в этой области. «It might be possible to obtain a great deal of information that is presently lac king in this field».
В схеме (а) чистый продукт выводится сверху, в то время как более высококипящий компонент только входит в колонку. «In (a) pure material is being taken off at the top, while the higher boiling component is just starting into the column».
Подобно многим другим открытиям, этот новый процесс был случайно обнаружен в то время, когда Реппе пытался окислить винилкарбазол в N-карбоновую кислоту. «Like many other discoveries, this new process resulted accidently while Reppe was try ing to oxidize vinyl carbazole to the N-carboxylic acid».
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Во время протекания реакции имеют место изменения в реакционной смеси. Субстрат исчезает, образуются продукты реакции и обратная реакция препятствует прямой. «While the reaction is proceeding, changes are taking place in the reaction mixture. Substrate is disappearing, the products of the reaction are being for med, and the forward reaction may be opposed by reverse process».
§ 144. Continuous Passive. Формула: to be + being + III форма смыслового глагола.
Употребляется тогда, когда нас интересует не столько само действие, сколько время его протекания, и когда подлежащее пассивно (см. § 133). Например:
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