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. The engineer ordered that the work (should) be finished.


. proposed that a procedure be developed for the purification of a series of standards.

1933 . . In 1933 Schmidt recommended that norleucine be added to the list of accepted amino acids.

, . The quinoid structure requires that the two central phenyl groups be coplanar.

, . It is necessary that they should do it.

. It is advisable that the work be finished.

. It is not necessary that this be done in the same kind of reaction.

. It is most important that we should have an unambiguous knowledge of the rates and activation energies.

, . It is of the utmost importance that anydrous conditions be maintained in order to prevent the protein from hydrolysing.

, . It is essential that the phenol solutions be perfectly clear and free of this lipid.

, . In many types of experiments it is essential that phage growth start almost simultaneously in all of the infected bacteria.

. . : to require, required, requirement. :

, . The characteristics required of the electrode material are that the ratio of secondary to primary particles should be as great as possible.

: -, , , , -, . The two basic requirements for the use of an added component are: first, that it reduce the partial pressure of one of original components more than it does the other; and second, that it be easily removed from the distillate.

16* 243


228. , . , , : to think, to hope, to suggest, to doubt, to postulate, to anticipate, to assume, to suppose; : thought, hope, suggestion, postulate, anticipation, assumption, supposition, hypothesis, doubt; : it is likely, it is unlikely, it is probable; : possibly, probably, perhaps. , ( , . 143).

:

, , . In the hope that Dieckmann cyclisation would yield a piperidane derivative we carried out the following experiment.

, - Mg++, . This suggests that the decrease in rate at high phosphate concentrations might be due to a depletion of the concentration of Mg++ available for activating the enzyme.

, . Possibly the strontium salt would decompose even more readily.

, , . The limiting current would probably have a very large temperature coefficient.

, . Perhaps such a boron compound would rearrange to a zwitterionic product as follows.

. According to this hypothesis the phage genetic material would be a modified form of the bacterial genetic material.

. -, , to expect, to appear. :

, . Temperature and solvent would be expected to play a role in this reaction.


 


(V) , (XXI). In (V), the situation is similar and one might expect to have some of (XXI) produced.

-, . The reaction could appear to involve a rearrangement.

229. would, might, could , .

would, might, could . , .

:

, , b , , . Even with symmetrical pinacols, groups a and b might migrate by different mechanisms, although this possibility is much less likely than with the unsymmetrical pinacols.

β- , , . The β-lignosulfonic acid would then have the following composition.

, , , . The other substance, present only in traces, could be a disaccharide derivative.

, , , . In all the examples cited, the relief of compression energy might provide some driving force for rearrangement, since in every case a less constrained is generated.

230. . :

1. :

: if + Present Indefinite....Future Indefinite.

:

, . If I come I shall see you.

, , , . The yield will markedly decrease if an inert solvent other than diethyl ether is employed)).

, .


If we raise the temperature the film will expand, allowing more hydroxyl groups to enter the water.

2. , .

: if + Past Indefinite....should (would) + Infinitive Indefinite.

:

, . If he came today, he would see you.

, . If the attacking radical had a greater affinity for hydrogen, then the hydrogen-abstraction process should be favoured.

, . It would be necessary to resort to a prior separation of the two elements if one had only their cathodic waves to work with.

3. , .

: if + Past Perfect... should (would) + Perfect Infinitive.

:

, . If I had come yesterday I should have seen you.

, - . If a free, bridged phenonium ion had been an intermediate, the product would have been largely the p-toluenesulfonate ester.

231. II III .

, : () , . (: , .) If I came (to-morrow) I should see you.

: , - . . If such was the case, one coniferyl aldehyde building stone would be attached to the next by a half-acetal linkage between the aldehyde group in the side chain and the phenolic hydroxyl group of the next building stone. This, however, is not the case.


, - : , . (: .) If I had come I should have seen you.

, . If we had not studied English we should not have known it.

, . If the split to ethyl phenylacetate had taken place through an anhydrous mechanism, ethyl ether would have been isolated.

1. Bo II III should would could might .

II to be were be should .

, ( ) . If you should (were to) start early to-morrow morning you would (could, might) be at your destination by evening.

, . If the reaction should proceed smoothly the end product might increase.

, . If it were (was) possible to measure such a tension between two different phases in contact, all our problems might be solved.

, . If the whole effect were to be traced to this cause, then our assumption would have been correct.

; , . This so-called ungreenable black is a very stable substance; if it were not, it would have little technical importance.

232. . II III . , if : were I you = if I were you; had he been here = if he had been here; should he come = if he should come; could one find = if one could find.


:

, , . Had the substances so isolated consisted of a mixture of a polysaccharide and a polypeptide the former would not have been expected to migrate in an electric field.

1865 ., , .

Cramer might have been credited with the discovery of alanine in 1865 had he taken the trouble to purify an amino acid fraction which undoubtedly was rich in alanine.

, . Were the only property of a molecule the force of attraction between it and its neighbours, all matter would eventually coalesce into the liquid or solid phase.

, , , .

Should we weigh the cord, we should find its weight so small as to be negligible.





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