The pyrimidines may be obtained by condensing I.
Oxazoles are produced on condensing phenacyl bromide with acid-amides (M.
The diketotetrahydrotriazoles, or urazoles, are formed by condensing urea derivatives with hydrazine salts, urazole itself resulting by the action of urea or biuret on hydrazine or its salts.
Triethyl silicol, (C2H5),Si OH, is a true alcohol, obtained by condensing zinc ethyl with silicic ester, the resulting substance of composition, (C2H5)3 SiOC2H51 with acetyl chloride yielding a chloro-compound (C2H5)3SiC1, which with aqueous ammonia yields the alcohol.
We may evaporate some of the solvent from the solution which has become weaker and thus reconcentrate it, condensing the vapour on the solution which had become stronger.
It is extremely hygroscopic and is 'used in synthetical organic chemistry as a condensing agent.
This steam condensing adds to the water in the pipe and naturally causes an overflow, which is led back to the boiler and re-used.
The more complex phenazines, such as the naphthophenazines, naphthazines and naphthotolazines, may be prepared by condensing ortho-diamines with ortho-quinones (0.
The mono-amino derivatives or eurhodines are obtained when the arylmonamines are condensed with orthoamino zo compounds; by condensing quinone dichlorimide or para-nitrosodimethyl aniline with monamines containing a free para position, or by oxidizing ortho-hydroxydiaminodiphenylamines (R.
The varying load against which a locomotive works, and the fact that a locomotive is non-condensing, are factors which reduce the margin of possible economy within narrow limits.
Gmelin availed himself of every publication he could, but he perhaps found his richest booty in the labours of Latham, neatly condensing his English descriptions into Latin diagnoses, and bestowing on them binomial names.
In order to separate the distillate into various fractions, and to remove as much of it as possible free from condensed steam, it is now usual to employ condensing appliances of special form with outlets for running off the different fractions.
7-trihydroxyxanthone, is found in the form of its methyl ether (gentisin) in gentian root; it is obtained synthetically by condensing phloroglucin with hydroquinone carboxylic acid.
Its tetramethyl-diamino derivative, which is formed by condensing formaldehyde with dimethyl-meta-aminophenol and subsequent elimination of water from the resulting diphenyl methane derivative, is the leuco base of pyronine, into which it passes by oxidation.
CH :CH (OH), formed by acting on formic ester with acetone in the presence of sodium ethylate, readily yields [1.3.51-triacetylbenzene, C 6 H 3 (CO CH 3) 3; oxymethylene acetic ester or formyl acetic ester or ß-oxyacrylic ester, (HO)CH :CH CO 2 C 2 H 51 formed by condensing acetic ester with formic ester, and also its dimolecular condensation product, coumalic acid, readily yields esters of [1.3.
Saturated steam is steam in contact with liquid water at a temperature which is the boiling point of the water and condensing point of the steam; superheated steam is steam out of contact with water heated above this temperature.
Paal has also obtained pyrrol derivatives by condensing acetophenone-acetoacetic-ester with substances of the type NH2R.
They are prepared by condensing thio-amides with a-haloid ketones or aldehydes, the thio-amide reacting as the tautomeric thio-imino acid.
Dihydrothiazoles, or thiazolines, are obtained by condensing ethylene dibromides with thio-amides; by the action of a-haloid alkylamines on thio-amides (S.
Darzens (Comptes Rendus, 1904, 139, p. 1214) prepares esters of disubstituted glycidic acids, by condensing the corresponding ketone with monochloracetic ester, in the presence of sodium ethylate.
Such a plate has the power of a condensing lens, and gives an illumination out of all proportion to what could be obtained without it.
Busch (Ber., 1905, 38, pp. 856, 4049) has isolated a series of bridged ring compounds which he describes as endo-iminodihydrotriazoles, the triphenyl derivative (annexed formula) being prepared by condensing triphenylaminoguanidine with formic acid.
Formic acid yields acridine, and the higher homologues give derivatives substituted at the meso carbon atom, N N +[[Hcooh-C 6 H 5 /Inc6h5->C6h4 C6h4 Cho Ch N N +Ch 3 000h->C 6 H 5 /IC 6 H 5 --C 6 H 4 < >C6h4 Coch 3 C]](CH3) Acridine may also 1:e obtained by passing the vapour of phenylortho-toluidine through a red-hot tube (C. Graebe, Ber., 1884, 17, p. 1 37 0); by condensing diphenylamine with chloroform, in presence of aluminium chloride (0.
Koerner (Ber., 1884, 17, p. 203) by condensing ortho-nitrobenzaldehyde with aniline, the resulting ortho-nitro-para-diamino-triphenylmethane being reduced to the corresponding orthoamino compound, which on oxidation yields chrysaniline.
Taurke (Ber., 1905, 38, p. 1663) by condensing silicon halides with alkyl chlorides in the presence of sodium: SiC14-1-4R Cl+8Na= SiR 4 +8NaCI; SiHC1 3 +3R.
The ketone, dihydroxyacetone, CH 2 OH CO CH 2 OH, was obtained by Piloty by condensing formaldehyde with nitromethane, reducing to a hydroxylamino compound, which is oxidized to the oxime of dihydroxyacetone; the ketone is liberated by oxidation with bromine water: 3H CHO + CH 3 NO 2 -- (CH 2 OH) 3 C NO 2 - (CH 2 OH) 3 C NH OH -- (CH 2 OH) 2 C: NOH - > (CH20H)2CO.
It also results on condensing acetylene, and on reducing phenylacetylene by zinc dust and acetic acid.
Those substituted in the benzene nucleus are obtained by condensing two molecules of a substituted benzyl and benzal chlorides.
A more general designation is "pyrogenic processes," which also includes such operations as leading vapours through red-hot tubes and condensing the products.
In the "Lusitania," the steam traverses vertical copper coils tinned inside and outside; the coils are crescent-shaped, a form which gives a greater condensing surface and makes the coils self-scaling.
Xanthene, C13H100, may be synthesized by condensing phenol with ortho-cresol in the presence of aluminium chloride.
OXIMES, in organic chemistry, compounds containing the grouping > C: N OH, derived from aldehydes and ketones by condensing them with hydroxylamine.
Acetonyl-acetophenone, C6H5.CO.CH2.CH2.CO.CH3, is produced by condensing phenacyl bromide with sodium acetoacetate with subsequent elimination of carbon dioxide, and on dehydration gives aa-phenyl-methyl-furfurane.
Of these the Etudes sur la condition de la classe agricole et l'Nat de l'agriculture en Normandie au moyen dge (1851), condensing an enormous mass of facts drawn from the local archives, was reprinted in 1905 without change, and remains authoritative.
The condensing apparatus must also be conditioned by the volatility.
For more efficient condensation - and also for shortening the apparatus - the central tube may be flattened, bent into a succession of V's, or twisted into a spiral form, the object in each case being to increase the condensing surface.
The condensing water enters at the top and is conducted to the bottom of the inner tube, which it fills and then flows over the outside of the outer tube; it collects in the bottom funnel and is then led off.
The details of the plant - the material and fittings of the still, the manner of heating, the form of the condensing plant, receivers, &c. - have to be determined for each substance to be distilled in order to work with the maximum economy.
The condensing plant varies with the volatility of the distillate.
When the vapours readily condense to a solid form the condensing plant may take the form of large chambers; such conditions prevail in the manufacture of arsenic, sulphur and lampblack: in the latter case (which, however, is not properly one of distillation) the chamber is hung with sheets on which the pigment collects.
The more volatile vapours pass over to the condensing plant, while the less volatile ones condense in the bulbs and are returned to the column at varying heights by means of connecting tubes.
The body of the still is made of copper, with a head and worm, or condensing apparatus, either of copper or tin.
The Weir, the condensing water circulates upwards through the tubes; in others, e.g.
Bamberger, Ber., 1888, 21, p. 1901) and is frequently used as a condensing agent.
Steam at high pressure exhausting into the atmosphere is still commonly used, but the great power required for raising heavy loads from deep pits at high speeds has brought the question of fuel economy into prominence, and more economical types of the two-cylinder tandem compound class with high initial steam pressure, superheating and condensing, have come in to some extent where the amount of work to be done is sufficient to justify their high initial cost.
In many mints the flues pass into condensing chambers where volatilized gold and silver are recovered.
Soc., 18 93, 63, p. 1 355); the latter type result on condensing alkylene diamines with a-diketones.
Sodamide was introduced by Claisen (Ber., 1905, 3 8, p. 6 93) as a condensing agent in organic chemistry, and has since been applied in many directions.
Lampblack is prepared by burning tar, resin, turpentine and other substances rich in carbon, with a limited supply of air; the products of combustion being conducted into condensing chambers in which cloths are suspended, on which the carbon collects.
It is purified by redistilling and condensing directly under paraffin.
The flux is moistened with water and exposed to a current of carbonic acid, which, on account of the condensing action of the charcoal, is absorbed with great avidity.
Zincke found that the products obtained by coupling a diazonium salt with a-naphthol, and by condensing phenylhydrazine with a-naphthoquinone, were identical; whilst Meldola acetylated the azophenols, and split the acetyl products by reduction in acid solution, but obtained no satisfactory results.
Meta-oxyazobenzene, C 6 H 5 N: N(1)C 6 H 4 OH(3), was obtained in 1903 by P. Jacobson (Ber., 1903, 36, p. 4 0 93) by condensing ortho-anisidine with diazo benzene, the resulting compound being then diazotized and reduced by alcohol to benzene-azometa-anisole, from which meta-oxyazobenzene was obtained by hydrolysis with aluminium chloride.
When the slit is narrow light is lost through diffraction unless the angular aperture of this condensing lens, as viewed from the slit, is considerably greater than that of the collimator lens.
In order to record line spectra it is by no means necessary that the receiving instrument (bolometer or radiometer) should be linear in shape, for the separation of adjacent lines may be obtained if the linear receiver be replaced by a narrow slit in a screen placed at the focus of the condensing lens.
At the other end of the collimator there is a condensing lens for bringing the rays into parallelism.
This range acts as a " breakwater " to the clouds, arresting and condensing the moisture which is carried northwards by the south winds.