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10




, . The Mexican source contains more admixed tigogenin, which complicates purification.

. The STY-RENE added retarded the polymerization.

, -, . Increased porosity appears to lead to increased catalyst stability and decreased attrition resistance, other things being equal.

, 60% MgC2 40% Mg2C2. Preliminary experiments indicated that a heated mixture of


coal powder and magnesium powder gave approximately 60 per cent of MgC2 and 40 per cent of Mg2C2.

, . Just how increased inductive power affects the electron bonds is not clear at present, however.

, -- . It seems evident that the solvation will decrease with decreased water content and with increased ortho methyl substitution.

193. . :

( , . Going home I met my friend.)

. : being + /// ( ). , , , . ( , . Being received the letter was opened.)

. : having + /// ( ). , , , . ( , . Having come home I had my tea.)

:

12% , . The yield was 12% of the dried wood, varying with the amount of hydrochloric acid used.

, - . Having used the summation convention we recognise four different products.

, , . Boric acid and potassium fluoroboride react in a cold concentrated aqueous solution producing crystals containing boron and potassium in a one-to-one ratio.

, , . Broadly speaking, organometallic compounds are compounds which have a direct union of carbon with a metal.

, 50 ,


60%, . The dialyzed solution was evaporated to dryness and the residue dried below 50 C, giving a nondeliquescent brown powder in 60% yield of the solids.

. .

:

100 , , , .

Menschutkin, examining the kinetics o the formation of quaternary ammonium salts in a variety of solvents at 100 C, found the slowest reaction in the aliphatic hydrocarbons, and the fastest in the aromatic alcohols.

, , Osmium tetroxide, being bulky reagent, normally adds to the less hindered side of an ethylene.

194. : + + . + : thus, so, , , .

:

, , . These variants are not lysogonic any more, and are susceptible to the phage, thus confirming the close association of the lysogenic condition with the change in the cell surface.

, , , m-, . Plots for given hydronium-ion concentrations give reasonably straight lines, showing that the part of the reaction due to m-nitrophenol is first-order therein.

195. . : , . :

,


, . Reaction of the original sulfide with chlorine yields products in which the carbon disulfide residue is detached, which speaks for the coordinate nature of the adduct.

.

:

, , , . It has recently been shown that the conductivity depends on the presence of oxygen, indicating ionisation of the peroxide rather than the ethane.

0,00020,0004%, 0,050,1 0,04% 10 . The optimum concentration of methyl red in the final solution is 0,0002 0,0004%, corresponding to 0,05 to 0,1 mi of the stock 0,04% solution in each 10 ml of the solution being analyzed.

, , , , , . The only identifiable product isolated in low yield, was again the disulphide, presumably implying reduction of the sulphonyl chloride.

, - . The diarylcobalt complexes have very small or zero dipole moments, indicating a trans-planar configuration.

196. . , , , , , . .

:

. The reaction is fairly slow, requiring several hours of reflux conditions.

-- = . In VB language the He to H bond is largely ionic, being best represented by the structure He = H.

, ,


. On the basis of analyses, the benzene nucleus is assumed to be partly hydrogenated, causing a decrease in the intensity of the color.

. Phenyl isocyanate reacts normally, giving acetanilide with methylberyllium iodide.

, , , , , . With the exception of manganese, whose complex is ionic in character, having a paramagnetic susceptibility corresponding to five unpared electrons these complexes must all be regarded as being bonded like ferrocene.

25 37 . The rate of photoreactivation of adsorbed phage particles is a function of the temperature, increasing by a factor of two in the interval from 25 to 37 C.

, , , 40%. The yields of diaryls are often rather better than those obtained with other diazo compounds, being sometimes of the order of 40%.

, . This is not surprising, in view of the fact that the acylarylnitrosamines undergo rearrangement, giving diazoesters.

(9) , . In mechanisms (9) the product composition is unrelated to the reaction kinetics, being determined thus.

, , .

The degree of hybridisation in the transition state depends mainly on the reagent, being similar for any one reagent.

β- . The oxime molecule can then leave the surface in the more stable β-configuration, leaving behind it the original oxygen atom of the oxime group.

6 , 3 , . When 6 ml of condensate has collected in the receiver, leaving 3 ml in the flask, the microburner is removed.

.


, . :

, --- , , - . On the other hand, methyl-n-propyl-ketoxime gives two amides as products of the Beckmann transformation, behaving as though both forms were present in solution, while methyl isopropyl ketoxime gives only one anide and behaves as a single substance.

197. . . ( ) .

: +-+ - . (. 1).

( , ), ( ). , :

1) , , ;

2) , , ;

3) , ;

4) , ;

5) .

.

:

L-allo D-allo, α-- . The diastereoisomers of these substances are designated by the prefixes L-allo arid D-allo, the latter denoting the configuration of the α-carbon atom.

, , , , . For the present purposes organometallic compounds may be defined as those having carbon-metal bonds, the word bond being taken to include all of chemical combination or linkage that do not involve an intermediate atom.


, . In many ways reduction resembles the action of a Grignard reagent, hydrogen entering the reactant molecule in place of an alkyl or aryl group. , , , , . . , . This theory assumed binding power as an intrinsic property of atoms, the number of bonds formed by an atom, its valency, being characteristic for each kind of atom.

3040% , , . The gases obtained contained 3040 per cent hydrogen, the remainder being the germanes, of which monogermane predominated.

, , . Electrophilic reagents are those which seek electrons, the most common being positive ions.

, , , 6,45. All the values found experimentally, are considerably higher, their mean being 6,45. , . π- . Here only one of the rings retains its symmetrical (and aromatic) character, the other being linked to cobalt by dative π-bonds from the two conjugated double bonds.

, . In alternant hydrocarbons, the charge distribution is, in the Huckel approximation, uniform throughout the ring, the charge on each carbon atom being unity.

, -. If a salt of a mono-ester of a dicarboxylic acid is used, the product is a natural ester of a dicarboxylic acid, the reaction then being known as the Brown-Walker reaction.

, , . Actually the opposite is the case, the velocity of bromination being independent of the concentration of the bromine but proportional to that of the hydrogen bromide.


, , , -, -. The reaction also falls into line with others where hydrogen is transferred as H-, the hydrogen being activated in the donor by an adjacent E-substituent.

-- , . Para-tolyl orthosilicate did not yield good results, silica being deposited.

- , 40 50 N. The Lederle sample, however, failed to precipitate all of the anti-A from the serum, only 40 of the 50 mg of antibody N being precipitated.

, , , , , . We can show that, polarisation effect being neglected, the distance of the lines joining centers of the attracting dipoles, and the angles which they make with it, have the following values.

(N ) N-, N . One rnole (N molecules) is excited by the absorption of N quanta, N being the Avogadro number.

I. .

, . A new technique having been worked out, the yields rose.

2. .

, ( ). The good solvating medium provides stabilization of a transition state similar to a (charge being created).

8. being (having been) .

:

, . The work (being) finished we went home.

, . The letter (being) written, I went to post it.

, . The experiment (having been) carried out we started a new investigation.


198. , with. , with. , , .

:

, , . . , . The above formula is for a column operating under total reflux, that is, with no distillate being removed.

, . With the isomerisation preceding the reaction, the yields were very low.

, 90% 1 2, . Experiment indicated that 90% of the reactions proceed according to reactions 1 and 2, with the former predominating.

, , . Measurements should not be attempted with gas bubbling through the solution, for the stirring causes high and erratic currents.

, , , 107. It is difficult to assess these effects numerically, but advocates of this interpretation consider that, with all the adverse influence acting jointly, an inefficiency factor of about 107 could be understood.

199. , with being. , with being (having been). , , , , being.

:

, - α- β-. Nearly all organic radicals studied have been planar, with the unpaired electron centred partially or wholly in a p-orbital on trigonal carbon, and interacting with neighbouring α- or β-protons.


(b), , . The model is oriented as in (b) with the carbon chain vertical and to the rear and the hydrogen and hydroxyl standing out in front.

being (having been), with. , , to be, : ( ), , III . to be .

with being: Thus, with the models in the position shown with group i above group b in both Fig. 19 and 21, it is clear that d is closer to a in Fig. 19, than in Fig. 21, and the same is true for groups f and . , , 1 b . 19, . 21, , d . 19, . 21, f .

, , with being (having been).

(22) (20), . Eq. (22) is simply a rearrangement of Eq. (20), with summation substituted for integration.

, . With the precision and resolving power available in modern X-ray spectroscopy, many of the lines have been resolved.

, α- (6), dl- (7). With the cc-methyle-ne group of the ketone protected by conversion to the benzylidene derivative (), methylation introduced an angular methyl group at the proper point, and the four dl-forms of structure (7) were all isolated.

, 35 . There is a rather high temperature coefficient for activation with a temperature optimum at about 35 C.


- , 10 , . This method was further developed and applied to the seven coliphages of the series by Swanslrom and Adams, with, resultant phage concentrations about ten-fold greater than those obtained with broth lysates.

, r, . As a first approximation assume that this conic section is a circle of radius r with the nucleus fixed at the center of the circle.

, , -. The degree of association extends over all ranges, with one-fourth of all molecules combined into polymers larger than the decamer.

30 350 , O2 8:1. An optimum conversion of aniline to azobenzene of 30% was obtained at 350 with a mole ratio of O2, to aniline of about 8: 1.

, . A number of derived and related compounds were prepared and tested with few results of any promise.

X, 6, = = 4,24. With the values of A derived from data of Table X, 6, = 4: 24.

0,2 , . Insert the dropping electrode and measure the current at 0,2 v with the gas stream diverted over the surface of the solution.

, , , . A preheater has proved unnecessary with the oxygen normally available.

200. , with . with , being, .

:

, Ni(BF2)2, . The product with analysis corresponding to Ni(BF2)2, was a creamy fluffy powder.


, . The intermolecular hydride removal occurs only between a tertiary ion and molecules with hydrogens bonded to tertiary carbons.

, z , . Compared to a linear molecule, with the z axis along the bonds, the ring and metal orbitals can be classified as follows.

, , , . Experiment established that crystals with the faces inclined to the right and to the left rotate the plane of polarized light in opposite directions.

, , . The aspirator, with its upper chamber full of water, is connected to the train.

, , 2. They demonstrated that at low temperatures interchange of optically active primary alkyls with the asymmetrical carbon atom in position 2 is possible.

. with .

:

, . This addition can give rise to four possible geometrical isomers, each existing as a number of non-separable conformation isomers.

201. . , , , . . .

(. 255). :

, . carry out this reaction was found unnecessary.





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