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XI. 3




26. , , , : water, sand, light, air, work, gas, steam, ice, blood, tar.

:

, . The idea was to throw light on the firmness of binding of groups by determining their relative migratory aptitudes.

. On exposure to sunlight, the peroxide is isomerized to the oxidoketone.

, . These salts are stable to water and merely dissociate to the component ions.

5075 , . They advocate an initial injection of 5075 ml citrated blood.

, . The use of dry gas is essential, since water is a component that is far from inert.

 


. This colour developed on subjecting the fabric to steam.

87% . After standing for some time, this solution is poured onto ice to give 87% of butylsulfide.

27. 1. : detection, description, attention, reaction, experience, experiment, evidence, throughput, activity, equilibrium, resonance, viscosity, diamagnetism, hydrolysis, alcoholysis, reduction, pyrolysis, addition, separation, distillation, dilution, substitution, methylation, alkylation, racemization, irradiation, ult-rafiltration, transfer, fission, dehydration, decomposition, sublimation, oxidation, deformation, tension, polygonisation, notation.

:

, , , . In the case, where differential detection is employed it will frequently be necessary to place the detector within the column thermostat to prevent condensation.

, , , . In order to keep the text as concise as possible, description is confined to methods in general use in the laboratories.

, . Constant attention to the slopes of the lines involved in an extrapolation is essential.

, . Experience has shown that glass-channeled cells tend to give poor base-line stabilities at elevated temperatures.

. Only experiment can settle that issue.

. Evidence for the simple formula and against a dimer are lacking.

1938 . . In 1938 experimental evidence was available.

, , . Throughput

1 . L. and M. F i s e r. Op. cit., p. 3, 14.


has been defined in a different ways, depending on what the writer wanted to emphasize.

, , . Neither component alone is effective as biological catalyst, but activity is restored when solutions of the components are mixed.

. Equilibrium is favourable at elevated temperatures because of entropy.

, , . Resonance accounts for the stable, inert character of this compound often described as arornaticity.

, . Viscosity would be expected to increase with the intermolecular forces and so with molecular size.

, , . Diamagnetism, or the tendency of the radicals to be thrust out of an applied magnetic field, is due to the effect of the field on the moving electrons.

5---2-. Subsequent hydrolysis and alcoholysis to ethyl ester and reduction with aluminium scale gave rise to ethyl 5-amino-2 thiophencarboxylate.

. Pyrolysis is substantially eliminated.

, , . Addition occurs fairly readily in spite of the fact that the carbon atoms at the ends of the diene system are both disubstituted.

, , , -, , . The migrating group can be transferred to another nucleus, but again it seems likely that transfer takes place from a rearrangement of the intermediate and not by fission of the nitraniline.

, . Dehydration, decomposition and sublimation may proceed independently or simultaneously on exposure of amino acids to different temperatures for varying times.


, , . It is obvious, for example, that, in general, dilution would favour intra-over intermolecular reactions.

, , . Sometimes, as with ethylamines, continued fractional distillation is satisfactory.

, , . Separation is complete after the two bands have moved apart a distance equal to their mean width.

. Racemisation may be brought about by four methods.

, I, -, , . Irradiation, at least in case of production of suprasterol I, appears to result in the closing of a ring, for only three double linkages are indicated for the compound.

16-α- 34 , 2 . 16-α-methylation increases anti-inflammatory activity by a factor of 34 and enhances liver glycogen activity by a factor of about 2.

. Ultrafiltration is also useful for concentrating and purifying phages.

, , . It will be noted that paraffin alkylation is favoured only at relatively low temperatures while the equilibrium for alkylation of aromatics is favourable.

28. , , , .

: purity, size, flow, volume, activity, rest, content, shape, height, temperature, distance, equilibrium, behaviour, constitution, transfer, rate, ratio, drop, load.

:

, . Treatment with antiserum was a method of purification as well as a test of purity.


, , 11. Estimates of particle size of several bacteriophages by electron microscopy and other methods are given in Table 11.

. Curves of this type usually correlate data for variation of flow or volume.

. These constants are computed without correction for water content and departure of the particles from spherical shape.

, . There is nothing to do, but accept the fact that accurate measurement of wave height is impossible.

1 16 . Without further purification the product was dissolved in cone. HC1 and set aside at room temperature for 16 h..

2,65 3d , 3,69 . In titanium interatomic distance is 2,65 times the diameter of 3b shell, whereas in nickel this factor is 3,69.

. A solvent is in equilibrium with solid complex.

, , , . Later, in collaboration with Wells, Osborne further characterized the proteins by showing a relationship between chemical constitution and immunological behavior.

He , , . It is not impossible that bacteriophages may have evolved from a primitive mechanism of sexuality originally developed for the purpose of transfer of genetic materials between bacterial cells.

, : , . Other factors, such as rate of distillation, reflux ratio, and pressure drop will be considered later.

hardness, volume, ease, composition, toughness, microstructure, weight, conductivity resistance, shrinkage, porosity, warping :


Grinding mills can be run at maximum load regardless of feed hardness or size by automatic control of the recirculated load. The control system automatically adjusts input feed in relation to volume of the load in the closed circuit.

Choice of Materials: Ease of manufacture begins with the choice of the material to be used. Here, manufacturers are primarily concerned with machinability. This term is sometimes mistakenly thought to be synonymous with hardness. However, it is determined not only by hardness, but by chemical composition, toughness, microstructure, and the material's tendency to harden. A wide range of ferrous materials is available to the designer. Aluminium alloys have light weight, are easily machinable, possess good heat conductivity, and have good abrasive resistance. These factors are advantageous for a pattern material. One alloy suited for such work contains 7 per cent Cu, 5 per cent Si, 0.15 per cent Ti, and remainder Al.

Problems sometimes encountered include shrinkage and porosity, warping during machining, etc. Proper gating and risering, including use of chills where necessary, will provide castings free from shrinkage. Freedom from gas porosity requires a good quality alloy which must be melted under conditions which minimize gas pickup.

29. , : type, problem, degree, evidence, concept, hypothesis, discussion, theory, criterion, scheme, apparatus, mechanism, method, mode, technique, condition, influence, direction, effect, operation, restriction, temperature. , of. , .

:

, . Antiseptics include many alkylated products that exemplify several different types of alkyl linkage.

, , , . At a time when the major problems of structure and stereocliemistry seemed largely solved, steroidal research received a tremendous stimulus when the therapeutic efficacy of cortisone was discovered.

1808 . The hypothesis of intermediate compound formation traces its origin as far back as 1808.

-, ,


. There seem to be different degrees of randomness even in rubber, which is indicated by its thermal properties.

, , . Although incidental to the discussion of oxidation, it is of interest that tertiary alcohols are not acylable by the procedure ordinarily used.

, , . The struggle between the unitary and dualistic theories of chemical affinity was finally resolved.

. This is a rather crude criterion of purity.

, , 1. With this in mind, the scheme of synthesis outlined in Fig. 1 was developed.

. Most of these patents are concerned with apparatus and methods of manufacture of such catalysts.

, , , . This systematic method of derivation serves a useful purpose for if all possible modes of substitution are considered, no isomer can be missed.

. The technique of paper chromatography was cited above.

, . . An important consideration in the measurement of any physical quantity is the maintenance of standard conditions of temperature, pressure, etc.

, . The direction of rearrangement will depend on two matters, which have to be taken in order.

, , - , . The effect of temperature, pressure, space velocity and benzenepropylene ratio with a phosphoric acidkieselguhr catalyst has been discussed by McAllister.

, -, . Here again the presence of two groups ortho to a nitro group seems to hinder the operation of resonance.

, ,


. The restriction of rotation introduces a new center of asymmetry and thus makes theoretically possible additional stereoisomers.

. More or less saturated chloroparaffins are formed, depending on the temperature of reaction.

30. , , - of. 1 , 20. , , -, . .

: knowledge, inspection, measurement, effect, evidence, bromination, determination, confirmation, activity, formation, decomposition, co-ordination, fission, addition, precipitation, separation, isolation, breakdown, oxidation, hydrogenation, infection, depletion, diffraction, polymerisation, insolubility.

:

. In the light of present-day knowledge of molecular structure, much of this material is now incorrect.

, 1071011 , . Inspection of a number of catalytic constants for water and hydroxide ion shows that the latter is usually between 107 and 1011 times as large as the former.

- N1N--, 10-310-7. Measurement of redox potentials has been used to follow the rate of bromination of N1N-alkylanilines in strongly acid solution, bromine ion concentrations in range 10-310-7 being used.

. Effect of cracking variables.

He .

1 . . , . . . . ., 1957, 31.


Unequivocal evidence of the lactone structure was not available.

. Determination of the constitution of the blue compound is not a simple matter.

. Confirmation of double-bond typos suspected must be sought elsewhere in the spectrum.

. summarise generally, activity of these compounds in these respects does not differ markedly from that of their benzene isologs.

I, II ; (l)n - - III, . Formation of either I or II would explain the observed stabilisation of the diboron tetrachloride; decompostion of the latter to (BCl)n and boron trichloride might occur by fission of the B-B bond, preceded by internal co-ordination of III, which would be prevented by filling of the vacant boron orbitals.

. Addition of methyl iodide causes immediate precipitation of hexamethylditin.

2- 4- , , 2-- . Separation of the 2- and 4-sulfonic acids is possible through the differing solubilities of their potassium salts, that of the former being the less soluble in water.

. Isolation of the intermediates can be dispensed with.

, . While deamination constitutes the chief method whereby breakdown of the amino acid takes place, it is by no means the only one.

- . Oxidation of ketones with potassium permanganate has been rather generally used.

16, 17- . Hydrogenation of the 16, 17-double bond proceeded in the proper steric sense.

2 . Infection of bacteria with heavily irradiated T2 phages arrests synthesis of ribonucleic acid.


, . Depletion of the ions in the solution will be negligible in this case so that another factor must be taken into account to explain the new discrepancy.

, , . .Diffraction of X-rays having other than the desired wavelength is of great interest.

, , , . In this chapter we shall see how polymerisation of a given substance is carried out or, at least, how it is best attempted.

. Insolubility of this compound precludes further investigations.

31. for from.

: progress, distillation, fractionation, involvement, hydrogenation, preparation, rotation, lysis, chromatography, conversion, chemisorption, freedom, isomerisation, recrystallisation polymerisation.

:

, , . Adsorption systems based on ion exchange phenomena have been prominent in recent work and hold particular promise for progress in this field.

, , , . The time required for distillation is shortened and, therefore larger volumes of material can be charged to a given column for fractionation.

He i- . There is no evidence for involvement of an i-steroid cation.

. The availability of the three double bonds for hydrogenation clearly argues against this view.

. Recently these were of interest as basic comonomers with acrylonitrile for preparation of dyeable fibers.


. This is definite evidence for restricted rotation in certain oximes.

, . We have measured the length of time required for lysis of a standard fluid bacterial culture.

, . An instrument based on the same principle has been developed for gas chromatography by James and Martin.

, . be sure, very little energy is required for conversion to a variety of other forms.

IV , . A possible scheme of activation energies for chemisorption 011 these oxides based on these considerations is given in Table IV.

. Freedom* from draughts is essential.

6β- 6α- . Isomerisation from the 6β- to the 6 α-orientation is attended with a marked dextrorotatory shift.

. Repeated recrystallisation from petroleum ether or methanol is necessary for rapid polymerisation.

32. by with.

: increase, filtration, oxidation, adsorption, reaction, chlorination, extraction, precipitation, digitonin, evidence, spectroscopy, diffraction, consideration, lack, hydroxylation, passage, solution (. , 136).

:

, , . Such is the case where increases in plate efficiency are accompanied by increase in holdup.

. The sodamidecan be removed by filtration.

- 1,6- 1,3-- . By periodate oxidation it was not possible to distinguish between an inter- and intra-molecular mixture of 1,6- and 1,3-bonds.

5 . . 65


. Depletion of the solution by adsorption or reaction is not allowed for.

, , . The trichloride can be produced in situ, in the melt, by chlorination of an oxide in the presence of graphite.

. Ligninsfrom straws and corncobs are often isolated by extraction with cold diluted alkali.

. On a small scale isocholesterol can be isolated more easily by preferential precipitation of cholesterol with digitonin.

To, , , , , . That the chair conformation is more stable than that of the boat is attested by physical evidence, including infrared and Raman spectroscopy, and electron diffraction, and by thermodynamic consideration.

-. The early work in alkylation was hampered by lack of such methods.

1,4- . The reactions proceed by 1.4-hydroxylation of the diene system.





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