(1) The effects of the various inorganic salts on the thermal decomposition of cellulose were investigated. (2) The combustion of cellulose in the presence of various inorganic salts was measured. (3) It was suggested that the organic vapour produced by the pyrolysis plays an important rôle in the combustion of cellulose and that the major action of the fire-resisting compounds is to prohibit the yield of this vapour. (4) The effect of the inorganic salts on the combustion of cellulose were classified and were explained from the two major factors: the yield of organic vapour and the lowering action of ignition temperature of the charcoal.
1. Dielectric constants and loss factors of timber tilia containing various amounts of water have been measured in the region of frequencies of 0.2–3000 M. C. 2. The dielectric properties of these materials at the high frequency region are found to depend upon the rotation of dipoles of water, free and bound, in timber. The empirical relation proposed by Cole and Cole are utilized for the explanation. 3. Their dielectric properties at lower frequencies may be attributed to the other causes such as the movement of ions in the material.
We have obtained −53.9×10−6 at 30° as the molecular diamagnetic susceptibility of purified cycloöctatetraene, and its temperature dependence exceeding 0.5 percent over the temperature range 30° to 80° has not been detected. The diamagnetic anisotropy of this molecule has been estimated −12.6×10−6 per mole on some assumptions, and the resonanceenergy 2.9 kcal. per mole from the thermal data. The relationship between the small anisotropy and the weak resonance character of this molecule has been discussed and explained qualitalively on the basis of the quantum mechanical considerations. Langevin’s theory and the original procedure of London’s method have been found to be unsuitable for the explanation of this small anisotropy.
Aceytlene was hydrogenated by palladium deposited on such carriers as carbon black, active carbon (Merck), Japanese acid clay, French chalk, silica gel, granular active carbon, and quartz sand, and the functions of the carriers were considered for individual cases. The catalysts deposited on the first four carriers catalyzed the hydrogenation in two distinct steps at 30° in the same manner as alumina and kieselguhr, that is, hydrogenation and polymerization of acetylene proceeded in the first step and then ethylene was reduced to ethane in the second step, showing a pronounced self-retardation of acetylene. It was suggested that the kind of carriers has connection with the appearance of various “active regions” with different ratios. When the granular active carbon was used as a carrier, the hydrogenations of acetylene and ethylene proceeded not in two steps, but simultaneously. This phenomenon was explained by the slow diffusion velocity of acetylene into the inner part of the granule. Powdering the catalyst, the reflection point appeared in the hydrogenation curve and the curve was very similar to that of silica gel, suggesting a similar mechanism of the reaction. When the quartz sand was used as a carrier, the hydrogenations of the two hydrocarbons occurred at the same time. This is explained by the retardation of the adsorption rate of acetylene by the deposited polymers to such an extent as the adsorption rate becomes to be rate-determining. It was shown, therefore, that the granular active carbon and quartz sand are not to be used in practice for the selective hydrogenation of acetylene.
Purified cotton and wood pulp were hydrolyzed in 3.5 N HCl for 4-120 hours at 30°. The hydrolyzed products were nitrated with the mixtures of H3PO4-HNO3-P2O5 at 0° for 6 hours. Acetone solutions of the nitrates were fractionally precipitated with ligroin, and chain length distribution curves were plotted. These curves show no positive proof of the presence of the weak bonds which split 5000 times faster than the usual glucosidic bonds. These are well explained with the submicroscopic structure of cellulose.
Purified cotton and wood pulp were hydrolyzed in 3.5 N HCl for 4-120 hours at 30°. The hydrolyzed products were nitrated with the mixtures of H3PO4-HNOS-P2O5 at 0° for 6 hours. Acetone solutions of the nitrates were fractionally precipitated with ligroin, and chain length distribution curves were plotted. These curves show no positive proof of the presence of the weak bonds which split 5000 times faster than the usual glucosidic bonds. These are well explained with the submicroscopic structure of cellulose.
(1) Visco-elastic properties of tar pitches in the softening range were measured by a dynamic method covering 3∼20 minutes of period. (2) No frequency dependence of viscosity was observed in this range of period. (3) Elastic effect was slight in this range of period. Its frequency dependence was appreciable. (4) Tar pitch is a simple Maxwellian body rheologically above the softening point. (5) Temperature dependence of viscosity was studied along the rate-process theory, and it was supposed that tar pitch has a highly associated or solvated structure, consistent with the present theory of the internal structure of coal.
Theoretical formulas of thermal diffusion coefficient D′ and its relation to ordinary diffusion coefficient D have been derived by applying the activated state method to the solution in which stationary thermal gradient exists. Regarding the solution of small solute molecules, whether it is electrolytic or nonelectrolytic, the agreement with experimental result is good, while, regarding the solution of large solute molecule or molten salt, the discreparcy amounts to one order of magnitude.
It was shown that stable surface films of nonpolar substances could often be formed on water by mixing them with stearic acid, and that in the resulting mixed films the nonpolar substance existed in the state of rather stable unit of particles, forming monoparticle films. The dimension of the surface particles could be calculated for some nonpolar substances. The mechanism of the film-stabilizing action of stearic acid was discussed and it was suggested that the different film-stabilizing substances would stabilize the film of nonopolar substance in a different manner.
Monomolecular film of novolac and some azo dyes, which are not capable of forming stable monomolecular films by themselves on the surrface of water, were prepared using stearic acid or cetyl alcohol as a stabilizer and their properties were measured and discussed. It was shown that the molecule of novolac lies rather flat on the surface of water. The remarkable effect of capric ion in the underlying water on the dye mono layers was discussed in connection with the molecular structure of the dye compounds.
The evaporation of silica is facilitated by the use of silica gel, instead of quartz. The silica film thus obtained is available as replica for the electron microscopy. The difference of the easiness of evaporation between quartz and silica gel is atributed to molecular constitutions. Under the assumption, that quartz consists of three dimensional net work of covalent linkage, while silica gel is constructed by linear chain having some oxygen bridges between, chains, vapor pressure is calculated, and the ease of evaporation is accounted for by the comparison to some usual metals.