bluuebunny/crossref_metadata_2025 huggingface dataset:
CONSTITUTION OF A WATER SOLUBLE HEMICELLULOSE FROM AMERICAN BEECHWOOD (FAGUS GRANDIFOLIA)
Authors: Adams G. A.
Published: May 2006

Extraction of beechwood chlorite holocellulose with hot water yielded a hemicellulose in 13.4% yield (based on original extractive-free wood) containing D-xylose 72%, D-galactose 11.0%, and uronic acid 13.2%. Purification of the crude hemicellulose by complexing with Fehling's solution yielded a chemically homogeneous fraction containing D-xylose 83% and 4-O-methyl-D-glucuronic acid 15.5%. Hydrolysis of the fully methylated hemicellulose yielded 2,3,4-tri-O-methyl-D-xylose, 2,3-di-O-methyl-D-xylose, 3-O-methyl-D-xylose, and 3-O-methyl-2-O-(2,3,4-tri-O-methyl-D-glucopyranosyluronic acid)-D-xylose in a molar ratio of 2:35:3:5. On the basis of the methylation data, periodate oxidation, reducing power determinations, and weight average molecular weight values a possible structure for the hemicellulose is proposed.
MECHANISM OF THE DECOMPOSITION OF ETHYLENE WHEN PHOTOSENSITIZED BY METAL VAPORS
Authors: Whalley E.
Published: May 2006

A detailed mechanism of the molecular split of ethylene into acetylene and hydrogen, which occurs when ethylene is photosensitized by Hg(3P1), is presented. It is suggested that the triplet ethylene molecule which is first formed isomerizes to a molecule of uncertain lifetime in which two hydrogen atoms act as "bridges" between the two carbon atoms. The hydrogen molecule which splits from the ethylene molecule is formed when these two atoms leave simultaneously. The experimental observations on the decomposition of ethylene when photosensitized by Cd(1P1) or Zn(1P1) are consistent with the primary interaction of the excited metal atom with either a C–H group or with the π electrons.
THE ATTEMPTED SYNTHESIS OF TWO HEXOSE PHOSPHONATE ESTERS
Authors: Hoskin F. C. G.
Published: May 2006

The synthesis of glucose-1-methylphosphonate and isopropyl glucose-1-methylphosphonate has been attempted. Although the intermediates were successfully prepared, deacetylation failed to give the desired products.
THE GROWTH OF BUTADIENE POPCORN POLYMER IN THE PRESENCE OF METHYL METHACRYLATE MONOMER
Authors: Miller Glenn H. , Bakhtiar Abolfath Khan
Published: May 2006

The rate of growth of butadiene popcorn polymer seed in the presence of methyl methacrylate monomer vapor was found to be logarithmic with time and very sensitive to the presence of hydroquinone in the monomer. The resulting butadiene – methyl methacrylate graft polymer was homogeneous in appearance. No satisfactory kinetic mechanism can be presented at this time.
THE HEMICELLULOSES PRESENT IN ASPEN WOOD (POPULUS TREMULOIDES): PART III. THE CONSTITUTION OF PENTOSAN AND HEXOSAN FRACTIONS
Authors: Jones J. K. N. , Merler E. , Wise Louis E.
Published: May 2006

Extractive-free aspen wood (Populustremuloides) was extracted with water, followed by alkaline solutions of successively increasing concentration, and finally with alkaline borate solution. Hemicellulose fractions (I–IX) were thus obtained, and some of these were further subdivided into components which formed water-insoluble copper complexes (A) and those which did not (B). Analytical data are recorded for each fraction.One of the fractions (V) represented 19% by weight of the original wood. Hydrolysis of the methylated material gave 2,3,5-tri-O-methyl-L-arabinose, 2,3,4-tri-O-methyl-D-xylose, 2,3-di-O-methyl-D-xylose, 2- and 3-mono-O-methyl-D-xyloses, and three acidic fragments as the major components.When V was treated with an enzyme preparation, 80% by weight of the material was hydrolyzed to simple sugars, and an enzyme-resistant polysaccharide fraction remained. Methylation of the latter, followed by hydrolysis, afforded, in addition to those methylated sugars described above, 2,3,4,6-tetra-O-methyl-D-mannose.A mannose-rich hemicellulose fraction (VIIIA) was also methylated and then hydrolyzed. The major products were 2,3,4,6-tetra-O-methyl-D-mannose, 2,3,6-tri-O-methyl-D-mannose, and 2,3,6-tri-O-methyl-D-glucose. The significance of these results is discussed.
THE PRINS REACTION WITH β,γ-UNSATURATED ACIDS AND AMIDES
Authors: Belleau B.
Published: May 2006

The acid catalyzed condensation of cyclohexenylacetic acid and its corresponding N-methylamide with formaldehyde was investigated. Good yields of the expected δ-lactone (V) or δ-lactam (IX) were obtained when trifluoroacetic acid was used both as catalyst and solvent for the reaction.
THE REACTION OF UNSATURATED CARBOHYDRATES WITH CARBON MONOXIDE AND HYDROGEN: I. BRANCHED-CHAIN CARBOHYDRATE FROM 3,4,6-TRI-O-ACETYL-D-GALACTAL
Authors: Rosenthal A. , Read D.
Published: May 2006

A new crystalline seven-carbon branched-chain carbohydrate has been synthesized by application of the oxo reaction to 3,4,6-tri-O-acetyl-D-galactal. Periodate oxidation of the sugar alcohol was carried out to determine its structure. Crystalline benzoate and p-nitro-benzoate derivatives were obtained.
THE REDUCTION, ENOLATE FORMATION, AND SOLVOLYSIS OF GRIGNARD REAGENTS IN OPTICALLY ACTIVE MEDIA
Authors: Allentoff Norman , Wright George F
Published: May 2006

The sec-butylbenzene produced by solvolysis of 2-phenyl-2-chlorobutane Grignard reagent in (+) 2,3-dimethoxybutane and benzene is optically inactive. The 2-↓-isopropyl-4-↑-methylcyclohexanols obtained by the reducing action of isopropyl Grignard reagent on racemic 2-↓-isopropyl-4-↑-methylcyclohexanone in (+) dimethoxybutane are optically active to the extent of 6 and 15%. The bromomagnesium enolates obtained by the action of isopropyl Grignard reagent on racemic 2-↓-isopropyl-4-↑-methylcyclohexanone in (+) dimethoxybutane regenerate the parent ketone in an optically inactive state but the diastereomeric 2-↑-isopropyl-4-↑-methylcyclohexanone also produced is optically active to the extent of about 6%.
THE INFRARED AND RAMAN SPECTRA OF HC(CD3)3 AND DC (CD3)3
Authors: Wilmshurst J. K. , Bernstein H. J.
Published: May 2006

The Raman spectra of liquid (CD3)3CH and (CD3)3CD were obtained photoelectrically together with depolarization ratios, and the infrared spectra of the corresponding gases were obtained from 3 to 35 μ. A vibrational assignment consistent with depolarization ratios and band contours has been made for the molecules on the basis of C3v symmetry. The spectra have been correlated with the spectra of (CH3)3CH and (CH3)3CD and modified assignments for two modes have been given for these molecules. Tentative assignments have been made for the 'inactive' A2 modes (which are 'active' if the molecule has symmetry C3) to explain some of the observed frequencies around 1000 cm.−1 which could not be satisfactorily assigned as summation or difference tones.
YIELDS IN U235 THERMAL NEUTRON FISSION
Authors: Baerg A. P. , Bartholomew Rosalie M.
Published: May 2006

Quantitative ion exchange and 4π counting techniques have been used to measure the yields of four nuclides not previously determined by mass spectrometric analysis. Values of 6.57, 6.30, 4.74, and 5.71% were obtained respectively for Ba139, La141, Sr89, and Sr91 relative to a value of 6.32% for the yield of Ba140. A precision better than 1.3% was achieved in the measurements.
OCCURRENCE OF 2,7-DIHYDROXY-4-ISOPROPYL-2,4,6-CYCLOHEPTATRIEN-1-ONE (7-HYDROXY-4-ISOPROPYLTROPOLONE) IN WESTERN RED CEDAR (THUJA PLICATA DONN.)
Authors: Gardner J. A. F. , Barton G. M. , MacLean H.
Published: May 2006

The tropolones of western red cedar were collected as the green copper chelates deposited on copper–bronze screen exposed to the vapor from the heated wood in commercial kilns. Decomposition of the chelates with hydrogen sulphide yielded a new tropolone as well as the expected thujaplicins. Its infrared and ultraviolet absorption together with hydrogenation and oxidation reactions established it to be 2,7-dihydroxy-4-isopropyl-2,4,6-cycloheptatrien-1-one. Synthesis was achieved by persulphate oxidation of γ-thujaplicin. The natural substance is identical with the 7-hydroxyhinokitiol obtained by Nozoe from the diazonium salt of 7-amino-hinokitiol and on the basis of color reactions and Rf appears to be the unknown "enol" previously noted by Zavarin and Anderson in paper chromatography of tropolone fractions of western red cedar and incense cedar. The concentration in the wood, determined by quantitative paper chromatography, ranged from 0.01 to 0.08%.
THE STRUCTURE OF RHYNCOPHYLLINE
Authors: Seaton J. C. , Marion Léo
Published: May 2006

It is shown that hydrolysis of rhyncophylline with dilute hydrochloric acid gives rhyncophyllal (C19H24O2N2), which contains an aldehyde group but no longer contains the methoxyl, the isolated double bond, and the carbomethoxy group originally present in the alkaloid. Rhyncophyllal is reduced by sodium borohydride to the corresponding alcohol, rhyncophyllal, and this is further reduced by lithium aluminum hydride to dihydrodesoxy-rhyncophyllal (C19H28ON2), which shows the properties of an aromatic amine. Reduction of rhyncophyllal by the Wolff-Kishner reaction gives rhyncophyllane (C19H26ON2), which, when dehydrogenated over palladium–charcoal, yields 3,4-diethylpyridine. Direct dehydrogenation of rhyncophyllal produces β-collidine. On the basis of these as well as previously described results a total structure for rhyncophylline is derived.
THE STRUCTURE OF LINSEED MUCILAGE. PART I
Authors: Erskine A. J. , Jones J. K. N.
Published: May 2006

The neutral polysaccharide component of linseed mucilage has been isolated and examined. On acidic hydrolysis it furnished mainly D-xylose and L-arabinose. Periodate oxidation experiments showed that the polysaccharide is of the branched chain type. Methylation experiments have confirmed this result and have given additional information on the structure of the polysaccharide.
ARSENIDES OF THE TRANSITION METALS: II. THE NICKEL ARSENIDES
Authors: Heyding R. D. , Calvert L. D.
Published: May 2006

Alloys of nickel and arsenic containing up to 60% As by weight have been studied by means of room temperature and high temperature Debye-Scherrer diagrams. Three compounds have been identified: Ni5As2, Ni12−xAs8 (maucherite), and NiAs (niccolite). The first of these is homogeneous from Ni5As2 to Ni4.8A2 at room temperature, and to Ni4.6As2 above 250 °C., while the latter is homogeneous from NiAs to Ni0.95As. Contrary to expectations the stability region of the compound Ni12−xAs8 is very narrow, and occurs at Ni11As8 rather than at Ni3As2. Evidence is presented in support of Hansen's contention that this compound has an incongruent melting point. Alloys in the region corresponding to Ni4.6As2 undergo two transitions below 200 °C, one of which is martensitic and produces a metastable phase, while the other is believed to result in the formation of a new compound, as yet unidentified. The diffraction patterns are discussed in some detail.
THE GAS PHASE REACTION OF METHYL RADICALS WITH HEXAFLUOROACETONE
Authors: Pritchard G. O. , Steacie E. W. R.
Published: May 2006

The photolytic and thermal decomposition of azomethane in the presence of hexafluoroacetone produces small amounts of fluorinated products, mainly fluoroform. The mechanism of this and related reactions is discussed. It is concluded that the proposed reaction.[Formula: see text]has an activation energy of about 6 kcal./mole, with a steric factor of about 10−5.
SOLVOLYSIS IN HYDROGEN AND DEUTERIUM OXIDE: II. STRONGLY SOLVATED SUBSTRATES
Authors: Robertson R. E. , Laughton P. M.
Published: May 2006

Rates of solvolysis are presented for a number of polar substrates in light and heavy water from which the rate ratios [Formula: see text] may be obtained. Compounds studied include methyl, o-methyl-, p-methyl-, p-methoxy-, and p-fluoro-benzenesulphonate, the α- and β-methylation series of alkyl methanesulphonates, methyl and isopropyl nitrate, methyl phosphate and sulphate, methane- and benzene-sulphonyl chloride, and t-butyldimethylsulphonium iodide. The oxyanion esters, despite wide variation in reactivities, show very small variation in the rate ratios which lie near 0.9. The values for the chlorides are 0.63, and for the sulphonium salt, 0.95. The failure of the rate ratios to reflect the mechanistic changes required by variation in the alkyl groups and oxyanions is attributed to the structure of initial state solvation and the easy saturation of ratio-affecting structural changes by small charge development in the transition state.
SEPARATION OF ENDOMYCINS A AND B, AND THEIR IDENTIFICATION AS MEMBERS OF THE POLYENE GROUPS OF ANTIFUNGAL ANTIBIOTICS
Authors: Vining L. C. , Taber W. A.
Published: May 2006

An unidentified Streptomyces species isolated from platings of "honey dew" of the fungus Clavicepspurpurea produced two antifungal antibiotics which were shown by paper chromatography to be identical with the two active components of endomycin, and also with helixins A and B. An examination of the ultraviolet absorption spectra of the three complexes showed maxima at wavelengths associated with two unsaturated systems containing four and six conjugated double bonds respectively. The two unsaturated components were separated by countercurrent distribution and shown to correspond to the two active fractions. The tetraene has been named endomycin A, and the hexaene endomycin B. Flavacid, a polyene complex also containing tetraene and hexaene components, is not identical with endomycin.
ADSORPTION STUDIES ON A SERIES OF HEAT TREATED SHAWINIGAN ACETYLENE CARBON BLACKS
Authors: Holmes J. M. , Beebe R. A.
Published: May 2006

An experimental study has been made of the adsorption of a nitrogen, sulphur dioxide, carbon dioxide, and ammonia on Shawinigan acetylene carbon black and several derivatives of this material produced by heat treatment up to temperatures of 3000°. The effect of the heat treatment of the Shawinigan carbon black on its adsorption of the polar and non-polar gases studied is compared with the behavior of other heat treated carbon blacks. In particular, the effect of the low oxygen content of the Shawinigan black is considered. The isosteric heats of adsorption for ammonia on the most highly graphitized material (Shawinigan 3000) have been calculated. The results are in general agreement with previous calorimetric work of this laboratory. A special type of hysteresis for the system ammonia – Shawinigan black has been observed. This may be due to a reversible swelling of the graphitic material.
CORRELATION OF O–H STRETCHING FREQUENCIES WITH pK VALUES FOR SOME PHENOLS
Authors: Bavin P. M. G. , Canady William J.
Published: May 2006

The O–H stretching frequencies, in carbon disulphide, of a number of phenols have been determined. Linear relationships were observed on plotting the stretching frequency against pKA in water. Polar substituted phenols were found to fall along one line, while phenols substituted with aliphatic groups were found to fall along another line of different slope. A change of slope is observed when the stretching frequencies of phenols are plotted against pKA measured in alcohol–water mixtures.Using Goulden's O–H stretching frequencies of carboxylic acids measured in carbon tetrachloride, an attempt has been made to explain the observed deviations from a single straight line in terms of electrostatic effects in the ionizing solvent. The results indicate that for the substances examined, such effects are not responsible for the observed deviations.
THE POLAR EFFECT OF THE β-NITROVINYL GROUP
Authors: Stewart Ross , Walker L. G.
Published: May 2006

The meta and para β-nitrovinyl derivatives of phenol and benzoic acid have been synthesized. The acidity constant, pKa, was determined for each of these compounds and from these values the following Hammett sigma constants were obtained for the β-nitrovinyl group: σmeta = 0.34, σpara = 0.26, σ− = 0.88. The relationship between these values and the orienting effect of the β-nitrovinyl group on electrophilic substitution is discussed.
EXCITED STATES OF ACETYLENE AND THEIR ROLE IN PYROLYSIS
Authors: Minkoff G. J.
Published: May 2006

Previous theories of acetylene pyrolysis are reviewed in the light of recent work by Minkoff, Newitt, and Rutledge. It is shown that the relatively large rates observed at the beginning of the induction period do not agree with mechanisms involving the intervention of comparatively stable dimers. The required kinetic form is obtained, however, if a triplet diradical is produced on the surface in a bimolecular process, followed by gas phase polymerization, with some chain ending on the surface. The detailed mechanism closely resembles Flory's scheme for liquid phase vinyl polymerization. The shape of the radical is discussed, and it is suggested that the trans-configuration leads to polymerization, while the cis facilitates dehydrogenation.
REACTION OF AMINO ALCOHOLS WITH CARBON DISULPHIDE
Authors: McKay A. F. , Skulski M. , Garmaise D. L.
Published: May 2006

ω-Amino alcohols possessing five or more methylene units between the amino and hydroxyl groups on condensation with carbon disulphide gave good yields of 1,3-di-(ω-hydroxyalkyl) thioureas. These symmetrically disubstituted thioureas on oxidation gave the corresponding 1,3-di-(ω-hydroxyalkyl) ureas.
THE SYSTEMS Li2SO4–K2SO4–H2O AND Li2SO4–Na2SO4–H2O AT 25 °C.
Authors: Campbell A. N. , Kartzmark E. M.
Published: May 2006

The 25° isotherm of the system Li2SO4–K2SO4–H2O shows the existence of the double salt, Li2SO4. K2SO4, whereas that of the system Li2SO4–Na2SO4–H2O yields no double salt but extensive solid solution of lithium sulphate in sodium sulphate. On the other hand, a study at 39.5 °C. of the latter system shows that the double salt, Li2SO4. Na2SO4, does form at this temperature, accompanied as before by solid solution of lithium sulphate in sodium sulphate. The transition temperature for the reaction[Formula: see text]is 29.3 °C. A further transition, of unknown nature, occurs between 49° and 57°.
THE ELECTRIC MOMENTS OF SOME N,N′-DISUBSTITUTED PIPERAZINES
Authors: George M. V. , Wright George F
Published: May 2006

The establishment of significant orientation polarizations for a series of symmetrically N-substituted piperazines including N,N′-dichloro-2,5-↑↓-dimethylpiperazine, which was prepared anew, confirms the report of Partington and contradicts that of Hassel. The existence of these moments is not compatible with the postulation of a favored chair conformation especially in consideration of the proton magnetic resonances of N.N′-dimethylpiperazine and N,N′-diformylpiperazine. On the other hand the experiments favor the postulation of flexible conformation for these piperazines.
THE PREPARATION OF AMINES AND HYDRAZO COMPOUNDS USING HYDRAZINE AND PALLADIZED CHARCOAL
Authors: Bavin P. M. G.
Published: May 2006

The reduction of nitro compounds to amines by ethanolic hydrazine and palladized charcoal probably proceeds through the nitroso and hydroxylamine derivatives. This reagent is shown to be useful for the reduction of azo to hydrazo compounds.
TRIARYLMETHANE COMPOUNDS AS REDOX INDICATORS IN THE SCHOENEMANN REACTION: III. THE DYES AND THEIR SPECTRA
Authors: Grant G. A. , Blanchfield R. , Smith D. Morison
Published: May 2006

A series of triarylmethane dyes were made by varying the substituents in the thiophene ring of the dye [4-(p-dimethylamino-α-2-thienylbenzylidene)-2,5-cyclohexadiene-1-ylidene]-dimethylammonium chloride. The spectra of the zinc salts of these dyes were shown to be similar to that of the dye formed in the Schoenemann reaction when the parent triarylmethane compound was used as an indicator. Neither of the absorption bands occurring in the 475 mμ or 625 mμ regions is affected by pH or buffer salts in the pH range 2.4 to 6.4 but both bands are hypsochromically shifted when the pH is lowered to 0.5. The substitution of 5-nitro and 5-acetamido groups in the thiophene ring results in the largest bathochromic and hypsochromic shifts respectively. Interpretation of the effect of substitution and pH was attempted employing existing theories on the relation between color and constitution.
THE PHOTOCHEMICAL OXIDATION OF ALDEHYDES IN THE GASEOUS PHASE: PART I. THE KINETICS OF THE PHOTOCHEMICAL OXIDATION OF ACETALDEHYDE
Authors: McDowell C. A. , Sharples L. K.
Published: May 2006

The photochemical oxidation of acetaldehyde has been studied in the gaseous phase at 20 °C. and a wavelength of 3130 Å. It has been established that when the pressure of oxygen is between 0.5 mm. and 150 mm. the reaction obeys the kinetic law:[Formula: see text]where k3 is the velocity constant for the propagating reaction [3]:[Formula: see text]and k6 is the velocity constant for the terminating reaction [6]:[Formula: see text][Formula: see text] is the rate of initiation of the photooxidation, i.e. the rate of formation of acetyl radicals, which are thought to be produced in one or both of the following ways:[Formula: see text]
THE PHOTOCHEMICAL OXIDATION OF ALDEHYDES IN THE GASEOUS PHASE: PART II. THE KINETICS OF THE PHOTOCHEMICAL OXIDATION OF PROPIONALDEHYDE
Authors: McDowell C. A. , Sharples L. K.
Published: May 2006

The photochemical oxidation of propionaldehyde has been studied in the gaseous phase at 23 °C. and a wavelength of 3130 Å. With pressures of oxygen varying from 0.3 mm. to 100 mm. Hg it has been established that the reaction obeys the same kinetic law as that found for the corresponding reaction with acetaldehyde, namely:[Formula: see text]where k3 is the velocity constant for the propagating reaction [3]:[Formula: see text]and k6 is the velocity constant for the terminating reaction [6]:[Formula: see text][Formula: see text]is the rate of initiation and it is regarded as being a composite quantity representing the rate of formation of propionyl radicals, which are thought to be the initiators of the oxidation chain. The propionyl radicals are thought to be formed by two processes: (a) from the subsequent reactions of free radicals produced in the primary free radical process which occurs when propionaldehyde absorbs a quantum of radiation at 3130 Å, and (b) from the subsequent reactions, with oxygen, of excited states of propionaldehyde, which are also thought to be formed by the absorption of light of wavelength 3130 Å.
DEOXYMERCURATION
Authors: Berg O. W. , Lay W. P. , Rodgman A. , Wright G. F.
Published: May 2006

The conversion of several stereoisomeric oxymercurials to alkenes (deoxymercuration) has been studied with hydrogen chloride in anhydrous and near-anhydrous methanol. In each instance the addition of water decreases the second-order rate. In benzene the addition of water to the anhydrous system first accelerates and then decreases the reaction rate. These results have been interpreted in support of molecular rather than ionic participation by hydrogen chloride. Since molecular participation requires the ↑↑ arrangement of alkoxy and chloromercuri groups for easy reaction it follows that oxymercuration also follows a molecular and not a "mercurinium ion" mechanism in the normal reaction.
SYNTHESIS OF PORPHYRINOGEN-LIKE COMPOUNDS (MIXED QUATERENES)
Authors: Brown William H. , French Warren N.
Published: May 2006

Three porphyrinogen-like compounds, or mixed quaterenes, have been synthesized. One quaterene contains a pyrrole and three furan residues while the others contain two pyrrole and two furan residues. The chief reaction in the preparation of these mixed quaterenes involves the condensation of a dimethylcarbino of furan at the α-position on a furan or pyrrole ring. Several previously unknown compounds of pyrrole and furan have been prepared as necessary intermediate.
NITRIMINO-(1H)PYRIDINIUM AND NITRIMIN0-(3H)THIAZOLIUM INNER SALTS: THE STRUCTURE OF SOME NITRIMINES IN THE LIGHT OF INFRARED STUDY
Authors: Taurins Alfred
Published: May 2006

Compounds previously known as nitraminopyridines and 2-nitraminothiazoles are formulated as nitrimino-(1H)pyridinium and 2-nitrimino-(3H)thiazolium inner salts on the basis of the infrared study. In the solid state, the three isomer nitriminopyridines do not exhibit any infrared absorption of the —NH group in the region 3400–3200 cm.−1 but show a wide band at lower frequencies in the region 2880–2550 cm−1. 2-Nitriminothiazole shows only a wide band between 3140 and 2270 cm.−1. These shifts of absorption bands can be correlated with structures derived from the classical nitrimino tautomeric forms in which the resonance effect stabilizes (1H)pyridinium and (3H)thiazolium cations, and a nitrimino group carrying a negative charge. n-Butylnitramine, a non-resonating compound, absorbs strongly at 3300 cm.−1, indicating that nitramino groups are not associated.
SLURRY TITRATIONS OF UNSTABILIZED CELLULOSE NITRATE
Authors: Gagnon Paul E. , Keirstead Karl F. , Newbold Brian T.
Published: May 2006

Slurry titrations were performed on unstabilized cotton and wood cellulose nitrates. The results for total sulphate were compared with those from gravimetric, 24-hour, and zero hydrolysis methods. The agreement was best in the case of wood cellulose nitrates. The ester sulphate contents obtained were also compared with those from 24-hour and zero hydrolysis. The agreement was again best in the case of wood cellulose nitrates. It was shown that slurry titration for the determination of sulphate acid ester could be used for wood cellulose nitrates containing not less than 100% sulphate ester, the error being −2.7 to −11.9%. For cotton cellulose nitrates, the results were not satisfactory.
L'ARYLATION DES QUINONES PAR LES SELS DE DIAZONIUM : II. SUR LA SYNTHÈSE DES 2,5-BISARYL-p-BENZOQUINONES
Authors: Brassard P. , L'Écuyer P.
Published: May 2006

not available
STRUCTURE OF AN ARABOGALACTAN FROM WHITE SPRUCE (PICEA GLAUCA (MOENCH) VOSS)
Authors: Adams G. A.
Published: May 2006

A water-soluble polysaccharide isolated from white spruce wood contained D-galactose, L-arabinose, and D-xylose in a molar ratio of 21:3:1. Hydrolysis of the fully methylated polysaccharide yielded 2,3,5-tri-O-methyl-L-arabinose (12 moles); 2,3,4,6-tetra-O-methyl-D-galactose (29 moles); 2,3,4-tri-O-methyl-D-galactose (34 moles); 2,6-di-O-methyl-D-galactose (0.5 moles); 2,4-di-O-methyl-D-galactose (45 moles); 2,3-di-O-methyl-D-xylose (5 moles); and monomethyl xylose (1 mole). When oxidized by periodate the polysaccharide consumed 1.18 moles of oxidant, and yielded 0.56 moles of formic acid per mole of anhydro-D-galactose. The D-xylose was attributed to the presence of a xylan mixed with the arabogalactan in the original polysaccharide preparation. The methylation and periodate oxidation data showed that the arabogalactan possessed a highly branched structure with the anhydro-D-galactose units being joined by 1 → 3 and 1 → 6 glycosidic bonds. All of the L-arabinose was present in the furanoside form as non-reducing terminal units.
SOME NEW SULPHONAMIDES AND DERIVATIVES OF BICYCLIC GUANIDINES
Authors: Kreling M.-E. , McKay A. F.
Published: May 2006

The preparations and bacteriostatic activities of some sulphonamide derivatives of the bicyclic guanidines are described. Some l-(2-hydroxy-3-(aryloxy)propyl)-2,3,5,6-tetrahydro-1-imidaz(1,2-a)imidazoles have also been prepared.
THE VAPOR PRESSURE OF LITHIUM IN THE REDUCTION OF LITHIUM OXIDE BY SILICON
Authors: Morris W. , Pidgeon L. M.
Published: May 2006

The vapor pressure of lithium over the system lithium oxide – calcium oxide – silicon has been measured using the gas entrainment method at temperatures between 970 °C. and 1025 °C. The experimental results are summarized in the form [Formula: see text] where P is in atmospheres and T in °A. The reaction, as usually written,[Formula: see text]does not describe the process completely.
SUR LES RÉACTIONS DES POLYESTERS AVEC LE TÉTRACHLORURE DE TITANE : I. LA RÉACTION DE L'OXALATE DE DIÉTHYLE AVEC LE TÉTRACHLORURE DE TITANE
Authors: Aubin Réal , Rivest Roland
Published: May 2006

not available
MOLECULAR SIZE AND CONFIGURATION OF CELLULOSE TRINITRATE IN SOLUTION
Authors: Huque M. M. , Goring D. A. I. , Mason S. G.
Published: May 2006

Viscosity and light-scattering measurements were made on several fractions and two unfractionated samples of cellulose trinitrate. The samples were prepared from bleached ramie, unbleached ramie, and cotton linters. The solvents were acetone and ethyl acetate. Viscosity was measured in a multishear viscometer designed for the purpose. Light-scattering measurements were made in a Brice-Phoenix Light-scattering Photometer modified to accommodate a cell which could be ultracentrifuged.The range of molecular weight investigated was from 6.5 × 105 to 25.0 × 105 The relationship between the z-average mean-square radius of gyration, [Formula: see text] and the z-average molecular weight was approximately linear in both solvents. The ratio of [Formula: see text] (where [Formula: see text] is the value of [Formula: see text] in the unperturbed state) was found constant in acetone but to increase with [Formula: see text] in ethyl acetate. This indicated that, whereas in acetone random coil configuration was attained, a configurational transition occurred in ethyl acetate in the molecular weight range investigated.The value of the exponent a in the relationship between intrinsic viscosity and molecular weight was found to be lower than unity but approximately equal in both solvents.The significance of the experimental data is discussed.
THE POLAROGRAPHIC REDUCTION OF DIAZOTIZED AROMATIC AMINES
Authors: Elofson R. M.
Published: May 2006

not available
THE REACTIONS OF ACTIVE NITROGEN WITH CYCLOPROPANE, CYCLOBUTANE, AND CYCLOPENTANE
Authors: Klassen N. V. , Onyszchuk M. , McCabe J. C. , Winkler C. A.
Published: May 2006

Cyclopropane, cyclobutane, and cyclopentane in order of increasing reactivity with active nitrogen yielded hydrogen cyanide and ethylene as the major products. The relative proportions of ethylene to hydrogen cyanide increased with number of carbon atoms in the reactant and with increase of temperature.
THE REACTIONS OF ACTIVE NITROGEN WITH CHLOROMETHANES
Authors: Sobering S. E. , Winkler C. A.
Published: May 2006

Cyanogen chloride and chlorine were the only gaseous products observed in the reaction of active nitrogen with carbon tetrachloride at 110° and 420 °C. The product yields tended towards limiting values at higher reactant flow rates, and increased with increase of temperature at all flow rates. The reactions of active nitrogen with chloroform and dichloromethane at 260° and 420 °C yielded hydrogen chloride, hydrogen cyanide, and cyanogen, in addition to cyanogen chloride and chlorine. The behavior of the product yields with reactant flow rates and temperature was similar to that of the products from carbon tetrachloride.
THE EXTRACTION OF PLUTONIUM FROM NEUTRON-IRRADIATED URANIUM BY URANIUM TRICHLORIDE AND BY MAGNESIUM CHLORIDE
Authors: McKenzie D. E. , Elsdon W. L. , Fletcher J. W.
Published: May 2006

The extraction of plutonium from neutron-irradiated uranium by uranium trichloride and by magnesium chloride has been examined in the temperature range 1150° to 1250 °C. The results of the uranium trichloride experiments have been used to evaluate the standard free-energy change of the equilibrium reaction [Formula: see text] These free-energy values have been used to predict the plutonium extraction in the magnesium chloride experiments on the assumption that the uranium trichloride, continuously formed from the non-equilibrium reaction [Formula: see text] rapidly established the above equilibrium with the plutonium in the uranium. Agreement between predicted and experimental results supports this assumption.A preliminary study of the kinetics of the MgCl2–U reaction showed that the initial rate of reaction is controlled by the distillation of magnesium metal from the reaction zone.
CYCLOHEXANE COMPOUNDS: II. SYNTHESIS AND STRUCTURE OF TWO STEREOISOMERIC 3-AMINO-1,2-CYCLOHEXANEDIOLS
Authors: Bannard R. A. B. , Hawkins L. R.
Published: May 2006

The stereoisomeric 1-ethoxy-2,3-epoxycyclohexanes were prepared from 1-ethoxycyclohexene-2 via 1-ethoxycyclohexene-2 bromohydrin. Ammonolysis of the lower- and higher-boiling oxides furnished 1α-ethoxy-2β-hydroxy-3α-aminocyclohexane and 1α -ethoxy-2β-hydroxy-3α-aminocyclohexane respectively. In a similar manner, 1α-methoxy-2α-hydroxy-3β-aminocyclohexane and lα-methoxy-2β-hydroxy-3α-aminocyclohexane were obtained from l-methoxycyclohexene-2 via 1-methoxycyclohexene-2 bromohydrin and the stereoisomeric 1-methoxy-2,3-epoxycyclohexanes. Ether cleavage of 1α-ethoxy- and lα-methoxy-2β-hydroxy-3α-aminocyclohexane gave 3α-amino-1α,2β-cyclohexanediol hydrobromide, from which the free base was obtained. 3β-Amino-1α,2α-cyclohexanediol was prepared similarly from lα-ethoxy- and 1α-methoxy-2α-hydroxy-3β-aminocyclohexane. The stereochemistry of the 3-amino-1,2-cyclohexanediols, 1-alkoxy-2-hydroxy-3-aminocyclohexanes, and 1-alkoxy-2,3-epoxycyclohexanes has been elaborated.
THE SEPARATION OF SATURATED AND UNSATURATED FATTY ACID ESTERS BY GAS–LIQUID CHROMATOGRAPHY
Authors: Craig B. M. , Murty N. L.
Published: May 2006

Fatty acid methyl esters are separated according to chain length by using washed silicone grease supported on 20–40 mesh C22 firebrick. By using a plasticizer on the firebrick support the same esters are separated according to both chain length and degree of unsaturation. Together the two procedures can be used to determine the component fatty acids in fats and oils. Nearly parallel linear relations are obtained for saturated, monoethenoid, diethenoid, and triethenoid methyl esters when the logarithm of emergence time is plotted against the carbon number of the fatty acid.
CONDUCTANCES OF CONCENTRATED AQUEOUS SOLUTIONS OF MIXED ELECTROLYTES
Authors: Campbell A. N. , Kartzmark E. M. , Sherwood A. G.
Published: May 2006

Equivalent conductances, viscosities, and densities were determined for solutions equimolar in two of the three salts lithium nitrate, ammonium nitrate, and silver nitrate. The three possible combinations of two salts were each studied at 25 °C and at 35 °C.The observed conductances and viscosities were compared with those of the single salt solutions at the same total ion concentration. The conductances were lower than the mean of the conductances of the single salt solutions. The viscosities were also lower than the mean viscosities.
L'ARYLATION DES QUINONES PAR LES SELS DE DIAZONIUM : IV SUR LA RÉACTION DE CES SELS AVEC LA 2,5-DIHYDROXY-p-BENZOQUINONE ET LA SYNTHÉSE DE LA 3-HYDROXY-2,5-BISPHENYL-p-BENZOQUINONE
Authors: Brassard P. , L'Écuyer P.
Published: May 2006

not available
LIGHT ABSORPTION STUDIES: PART XI ELECTRONIC ABSORPTION SPECTRA OF NITROBENZENES
Authors: Forbes W. F.
Published: May 2006

The spectra of nitrobenzenes are discussed in terms of previously proposed hypotheses relating electronic interactions and ultraviolet absorption spectra.
SYNTHESES OF SUBSTITUTED GUANIDINES
Authors: Gagnon Paul E. , Boivin Jean L. , Zauhar Joseph
Published: May 2006

Ethyl-, propyl-, and benzyl-guanidine nitrates were prepared from amine nitrates and calcium cyanamide or dicyandiamide. Carboxyalkylguanidines were made by condensing the corresponding amino acids with guanidine carbonate in aqueous medium. All the guanidine nitrates, except the benzyl derivative, were converted into the corresponding nitroguanidines by treatment with concentrated sulphuric acid. Esters and metal salts of 1-(α-carboxyalkyl)-2-nitroguanidines were also prepared.
THE HEMICELLULOSE OF WHITE ELM (ULMUS AMERICANA) II. CONSTITUTION OF THE METHYL GLUCURONO-XYLAN
Authors: Gillham J. K. , Timell T. E.
Published: May 2006

The wood of white elm (Ulmusamericana) has been found to contain less xylan than most other hardwoods. Partial hydrolysis of the hemicellulose component yielded an aldotriouronic acid, a glucuronosyl xylose, 2-O-(4-O-methyl-α-D-glucopyranosyluronic acid)-D-xylopyranose, 4-O-methyl-D-glucuronic acid, and galacturonic acid.Hydrolysis of the fully methylated polysaccharide gave a mixture of 2-O- and 3-O-methyl-D-xylose, 2,3-di-O-methyl-D-xylose, 2,3,4-tri-O-methyl-D-xylose, and 2-O-(2,3,4-tri-O-methyl-α-D-glucopyranosyluronic acid)-3-O-methyl-D-xylopyranose in a molar ratio of 6:124:1:14. The number-average degree of polymerization of the methylated hemicellulose was 133 and that of the native polymer 185. On the basis of this and other evidence it is suggested that the xylan is linear and contains 185 1,4-linked β-D-xylopyranose residues, every seventh of which carries a single terminal side chain of 4-O-methyl-D-glucuronic acid attached by an α-glycosidic bond through C2 of the xylose. The number of acid groups is larger than in other hardwood hemicelluloses so far studied.
THEORETICAL ASPECTS OF THE UNIMOLECULAR DECOMPOSITION OF NITROUS OXIDE
Authors: Gill E. Kerry , Laidler Keith J.
Published: May 2006

The kinetic data for the unimolecular decomposition of nitrous oxide, recently analyzed by Johnston, have been considered from the standpoint of the theories of unimolecular decompositions. Particular attention is paid to the high-pressure first-order rates, the low-pressure second-order rates, and the pressure range over which the rates fall off. A normal-mode analysis is made for the molecular vibrations, and calculations are made on the basis of N. B. Slater's theory. It is found that when the change of multiplicity is taken into account the Slater theory gives a satisfactory interpretation of the high-pressure behavior, but gives rates that are much too small in the low-pressure region. The theories of Hinshelwood, Kassel, and Rice and Ramsperger account more satisfactorily for the rate of activation, and Kassel's theory accounts for the pressure fall-off. A modified theory of unimolecular reactions is proposed to explain the observed results.
LIGHT-SCATTERING STUDIES OF COPOLYMERS: I. EFFECT OF HETEROGENEITY OF CHAIN COMPOSITION ON THE MOLECULAR WEIGHT
Authors: Bushuk W. , Benoit H.
Published: May 2006

The classical light-scattering theory for polymer solutions is extended to solutions of copolymers which may be polydisperse in chain composition as well as in molecular weight. It is shown that much too high molecular weights will result from light-scattering data for copolymers owing to fluctuations in chain composition; the magnitude of this effect increases rapidly as the absolute value of the refractive index increment approaches zero. The methods for determining the usual weight-average molecular weight and polydispersity of composition are described.The theory was tested with experimental results on: (1) a mixture of polystyrene and poly(methylmethacrylate), considered as a copolymer with the highest possible polydispersity of composition; (2) a high conversion, statistical copolymer of styrene and methylmethacrylate (copolymer I); and (3) a block copolymer of the same monomers (copolymer II). The apparent molecular weight for copolymer I (Mw = 1.83 × 105) varied markedly with refractive index increment in much the same way as the total molecular weight for the mixture. The molecular weight of copolymer II (Mw = 1.20 × 106) remained essentially constant in the same series of solvents. The polydispersities of composition obtained were 0.72 and 0.05 for copolymer I and II respectively compared with the maximum possible value equal to 1.0.
VOLTAIC CELLS IN FUSED SALTS: PART V. THE SYSTEMS Sn/SnCl2 (KCl–NaCl), Fe/FeCl2 (KCl–NaCI), and Mn/MnCl2 (KCl–NaCl)
Authors: Flengas S. N. , Ingraham T. R.
Published: May 2006

Using a Ag/AgCl (KCl–NaCl) reference electrode, the standard electrode potentials of the systems Sn/SnCl2 (KCl–NaCl), Fe/FeCl2 (KCl–NaCl), and Mn/MnCl2 (KCl–NaCl) were determined at 700 °C and found to be 0.370 v, 0.520 v, and 1.205 v respectively. In each of the systems the Nernst equation was found to be applicable over the range of concentrations investigated.The effect of temperature on the electromotive forces of the above cells was measured and the heats of the cell reactions were calculated from the data.
SULPHINIC ACIDS AS ANALYTICAL REAGENTS
Authors: Forrest T. P. , Ryan D. E.
Published: May 2006

The "specific" action of sulphinic acids with metal ions is not limited to compounds in which there is direct attachment of the —SO2H group to an aromatic ring. Since both aliphatic and aromatic sulphinic acids react similarly the assumption that an aromatic group is necessarily co-ordinated to the metal atom through its π system is not valid; the precipitated products are simple salts of the acids. Ferric iron yields at least two products with sulphinic acids. Ceric cerium is reduced in acid solution but an orange-yellow precipitate containing cerium is obtained from acetate-buffered solutions. Naphthalenesulphinic acid may be used to quantitatively precipitate [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text] [Formula: see text].[Formula: see text] [Formula: see text]
POTATO X VIRUS: PART II. PREPARATION AND PROPERTIES OF PURIFIED, NON-AGGREGATED VIRUS FROM TOBACCO
Authors: Reichmann M. E.
Published: May 2006

When sap from tobacco, infected with potato X virus, was dialyzed against 0.05 M and then against 0.005 M sodium citrate, no aggregation of the virus was detected after ultracentrifugation. Flow birefringence measurements were made to compare virus preparations obtained by ultracentrifugation of untreated sap and of sap that had been treated with various buffers. Only versene and citrate were found to prevent aggregation. The influence of pH in the range 5.7–7.3 was very slight. Possible explanations of this effect are discussed.Nitrogen and phosphorus content and the sedimentation constant of the purified, non-aggregated virus are reported.
THE CONDENSATION OF 3-AMINO-5-PYRAZOLONES WITH ALDEHYDES SYNTHESES OF 5-PYRAZOLONOGUANIDINES
Authors: Gagnon Paul E. , Boivin Jean L. , Zauhar Joseph
Published: May 2006

3-Amino-5-pyrazolones did not react with guanidine in aqueous solution, but with aldehydes in the presence of piperidine, the amino group was removed in some cases. 5-Pyrazolonoguanidines were synthesized by the direct fusion of 3-amino-5-pyrazolones and dicyandiamide. The infrared spectra of the pyrazolone derivatives prepared are briefly discussed.
THE PRINCIPLE OF EQUIVALENCE CHANGE IN OXIDATION–REDUCTION REACTIONS
Authors: Halpern J.
Published: May 2006

The principle of equivalence change predicts that oxidation–reduction reactions between 1-equivalent oxidants and 2-equivalent reductants (or vice versa) will, in general, be slow, since they must proceed either through termolecular paths or through the formation of unstable intermediates. In this paper, the kinetics and mechanisms of a number of reactions of this type are examined and an attempt is made to assess the validity of the considerations on which this principle is based. Among the reactions considered are (1) electron transfer between metal ions; (2) oxidation of metal ions by oxygen; and (3) reduction of metal ions by hydrogen. In each of these cases it is found that the principle of equivalence change has only limited validity and that a number of other factors are important in determining the relative rates and mechanisms of reactions of different equivalence type. Among these are the formation of stabilized intermediate complexes between oxidant and reductant and the possibility of unstable intermediates acting as carriers in chain reactions. In reactions of thallium(I) or thallium(III) with 1-equivalent metal ions, thallium(II) is formed as an intermediate. Some of these reactions are not as slow as expected, apparently because of favorable entropies of activation. Several of the reactions examined proceed simultaneously through bimolecular and termolecular paths, the latter being favored because of lower activation energies.
MECHANISMS OF REDUCTION OF CHLOROAQUOCHROMIUM(III) IONS IN ACID MEDIA
Authors: Elving Philip J. , Zemel Bernard
Published: May 2006

The polarographic behavior of the hexaaquochromium(III) and dichlorotetraaquochromium(III) ions was observed in the absence of maxima suppressors, and in the presence of various concentrations of perchloric acid, hydrochloric acid, and neutral salt. The polarographic waves obtained for each Cr(III) species in the different media were analyzed by plotting the function log[i/(id − i)] vs. E; the plots generally consist of two straight lines intersecting at about the half-wave potential and can best be explained by assuming two different concurrent mechanisms for the electron transfer process: the direct transfer of an electron to the Cr(III) ion from the electrode at the mercury–solution interface, and the transfer of an electron to Cr(III) from a Cr(II) ion produced at that interface. Only for the dichlorotetraaquochromium(III) ion in 12 M HCl does the direct transfer process appear to be dominant. Polarography of Cr(III) in the latter medium before and after reaction with the medium shows no change in [Formula: see text] corresponding to the shift observed in the ultraviolet spectra; this is accounted for by the "catalytic" degradation, i.e., the loss of chloride of the higher chloro complexes due to the rapid anion transfer mechanism for the electron transfer process between halo Cr(III) and Cr(II) ions.
BROMINATION OF STEROID 20-KETALS
Authors: Amos Arthur A. , Ziegler P.
Published: May 2006

Bromination of 3α,12α-diacetoxypregnan-20-one ethylene ketal provided in good yield the corresponding 21-monobromo compound. This product, on acid hydrolysis and subsequent acetolysis, gave the known 3α,12α,21-triacetoxypregnan-20-one. Acid hydrolysis of the bromoketal, followed by Faworsky rearrangement, led to 3α,12α-diacetoxy-17α-methyletiocholanic acid methyl ester.
STERIC INHIBITION OF RESONANCE: I. 9-NITROANTHRACENE AND 9,10-DINITROANTHRACENE
Authors: Trotter James
Published: May 2006

Detailed X-ray analyses of the crystal structures of 9-nitroanthracene and 9,10-dinitro-anthracene have shown that the nitro groups are tilted out of the planes of the aromatic rings by 84.7° in the nitro derivative and 63.7° in the dinitro. The decreases in resonance interaction resulting from these deviations from coplanarity have been correlated with the characteristic vibration frequencies of the nitro groups.
ORBITAL CONSTRUCTIONS AND ELECTRON POPULATIONS IN THE TRANSITION ELEMENTS
Authors: Trost W. R.
Published: May 2006

Orbital constructions and electron populations for the bands in the transition elements have been worked out. With the assumption of uniform density of states in delocalized bands among nearest neighbors, it is possible to predict correctly the lattice elected by the elements. Manganese and iron are exceptions. Numerical values for electron populations in the several s, p, d, and hybrid bands, including their bonding, antibonding, and non-bonding levels, are obtained.
THE DIELECTRIC CONSTANT AND DIPOLE MOMENT OF 1,3-DIOXANE
Authors: Walker R. , Davidson D. W.
Published: May 2006

not available
ULTRAVIOLET ABSORPTION SPECTRA AND ACIDITIES OF ISOMERIC THIATRIAZOLE AND TETRAZOLE DERIVATIVES
Authors: Lieber Eugene , Ramachandran J. , Rao C. N. R. , Pillai C. N.
Published: May 2006

The ultraviolet absorption spectra of 5-(substituted)amino-1,2,3,4-thiatriazoles and the corresponding isomeric 1-substituted-tetrazoline-5-thiones have been studied. The spectra and the dipole moments of the 5-(substituted)amino-1,2,3,4-thiatriazoles eliminate the possibility of meso-ionic structures for these compounds. The dipole moments of 5-amino-, 5-methylamino-, and 5-dimethylamino-1,2,3,4-thiatriazole were all high but approximately of the same value (5.77 to 5.84 D). This suggests that the amino thiatriazoles are best represented by conventional covalent structures with significant ionic resonance contributions. The thiatriazole ring system exhibits a characteristic absorption maximum at 250–255 mμ and an electron-withdrawing effect approximately equal to the tetrazolyl ring system. The tetrazolinethionolyl ring system is similarly electron-withdrawing. The relative acidities of the 1-substituted-tetrazoline-5-thiones and the 5-alkylmercaptotetrazoles have also been studied and the results support the observations made on the basis of their ultraviolet absorption spectra.