The authors have investigated the electric properties of trimethylacetic acid in the liquid and solid states. From the markedly small values of dielectric constant and conductivity, combined with the results of the X-ray investigation, it is proposed that the crystal of the room temperature phase is composed of nonpolar dimer units having disordered orienation.
The surface area of cokes from humic acid and metal-humates and the absolute reaction rates of these cokes to carbon dioxide at various temperatures have been determined by the same method and procedure as those described in the first paper. The specific surface area of cokes from metal-humates are about two or five times larger than the coke from humic acid, and this increase is expected from the well-known fact that when carbonaceous materials are carbonized with inorganic salt an increase in the surface area is obtained. The specific reaction rates per unit surface area Ka of these cokes and carbon dioxide can be expressed by an equation K_a=A exp. (-E/RT), and the values of A and activation energies E have been determined. The activation energies of cokes from humic acid, Ca- and Mg-humates are about 95 kcal./mol. and a large difference is not seen among them, but those of cokes from Fe-, Al- and Na-humates are about 25-40 kcal./mol. smaller than H-coke. The experimental values of A for cokes from humic acid, Ca- and Mg-humate are in satisfactory agreement with those expected from the application of the absolute reaction rates theory to the reaction mechanism already presented in the first paper, but those of A for cokes from Fe-, Al- and Na-humate are much smaller than expected from the theory. These results may be considered to indicate that the more complicated reaction must be occurring for cokes from Fe-, Al- and Nahumates. Calcium and magnesium impurities have effects of decreasing the specific reaction rates per unit surface area of the coke from humic acid to carbon dioxide and on the other hand, aluminium, especially iron and sodium impurities at lower temperatures have great effects of increasing the specific reaction rates. The effects of these sodium and iron impurities agree well with the earlier results and the present results also confirm that the catalytic effects of impurities in coke play an important role in the absolute reaction rates of the coke-carbon dioxide system, which was assumed in previous papers. By considering the effects of metallic impurities on both the specific surface area of cokes from humic acid and the specific reaction rates per unit surface area of the coke with carbon dioxide, all metallic impurities investigated increase the relative reactivity of the coke from humic acid and for example, sodium impurities increase the apparent reactivity of the coke about 103 times at 700°C.
The rate constants of the thermal dissociation of 1,1-dimethyl, 1,3-diethyl, 1,3-diisopropyl, 1,1, 3-triethyl, 1, 3-dihexyl, 1,3-dibenzyl, 1, 1-diethyl-3-isopropyl and 1,3-di-t-butyl ureas in n-butyric,n-caproic,n-capric, phenylacetic and benzoic acids were deter mined. The effects of substituents and those of solvents on the reaction rate were discussed. The transition state of the dissociation containing two fatty acids and one urea molecule was considered and the experimental results were reasonably explained by the proposed mechanism.
(1) Ethylisopropoxychlorosilanes have been prepared and characterized. (2) By the thermal reaction of partially isopropanolysis product of ethyltrichlorosilane, linear ethylisopropoxypolysiloxanes containing from 1 to 3 silicon atoms and cyclotrisiloxane have been prepared and characterized. (3) Ethyldiisopropoxychlorosilane and isopropoxypolysiloxanes were refluxed and the two compounds of the series of linear ethylisopropoxypolysiloxanes in which one terminal group is the ethyl one have been synthesized and characterized.
The electronic images have been observed on 5 types of the catalysts for ammonia synthesis, which are different in promotercomposition. On heating the oxides from 750 to 900°C, the images of different kinds which were characterized by their respective promoters compositions appeared after a few minutes. On reduction, some of the images remained, while the others disappeared, and during the periods of five to thirty minutes of the reduction, the images turned to the respective characteristic ones again, sometimes being quite different from those of the oxides. On the additional observations, a part of the images weakened or disappeared and rather the homogeneous images over the whole sections became to be observed by raising thetemperature. Comparing the image with the optical, the net work of the emission after the reduction corresponds to cracks on the section. When the microscopic structure of the section thoroughly polished and etched with hydrochloric acid is adopted for comparison with the above optical image, grain boundaries in the oxide always correspond to the cracks. Therefore, the electronic images on the oxide are not always related to the grain boundaries. Qualitative explanations on respective promoting effect of alumina, lime and silica are yielded from view point of the electronic image. It has been proved from the observations of the electronic as well as the optical images that there are the following 3 types of regions which are rich in potash, i.e. the grain boundaries, particular interfacial grains and some of the sub-grains into which the parent grains are divided. When references are made to the results of the activity for ammonia synthesis, surface area and etc., together with that by H. Kobayashi who has described that the activity is greatly enhanced by the larger amount of potash insoluble in water, the estimation shows that probably potash existing in the sub-grains above may most contribute to the activity for ammonia synthesis.
The quantitative relations between the degree of deviation from coplanarity of the molecular configuration and the ultraviolet absorption spectrum as well as the extent of conjugation for the biphenyl-type compounds have been determined by calculations based on the molecular orbital method. On the basis of the results, the spatial configurations of biphenyl, o-methylbiphenyl, o,o′-dimethylbiphenyl, fluorene, 9,10-dihydrophenanthrene, 4,5-methylene-9,10-dihydrophenanthrene, 2, 7-dihydro-3,4-5,6-dibenzoxepin, and 2, 7-dihydro-3,4-5,6-dibenzazepinium-1-spiro-1'″piperidinium bromide have been discussed.
1) We attempted to prove that the polarisation characters, being measured as to a whole cell, can be attributed to each single electrode. This attempt was verified by most of the experiments. 2) The above success may be one of the experimental justifications to use a simple series circuit as the equivalent circuit of a conductivity cell. 3) Discordant results appearing in “N/100 measurements” are to be studied in more details.
1) Semicarbazones and guanylhydrazones of 4-nitrocinnamaldehyde, 4-nitrobenzalacetone, α-bromo-4-nitrocinnamaldehyde, and 1-(4-nitrophenyl)-2-bromo-1-buten-3-one, nitromethane derivatives of 4-nitrobenzaldehyde, 4-nitrocinnamaldehyde, and α-bromo-4-nitrocinnamaldehyde, and thiosemicarbazones of 4-amino, 4-acetamido-, and 4-nitroacetophen-ones were prepared for evaluation of their antibacterial activity. 2) Condensation of the acetophenones with thiosemicarbazide was found to proceed smoothly at pH 3.2 but not at pH 7.
1) On the principle of the colorimetry of nitrite produced by enzymatic reduction, a method of microdetermination of nitrate was established. 2) This method can be applied to 10–100μM/1. nitrate solution. 2 ml. of the solution (1.2–12μg. NO−3 or 0.28–2.8μg. nitrate-N) is sufficient for an analysis. 3) This method is successfully applied to the estimation of nitrate in human urine, horse serum, spinach leaf extract, sea water and rain water.
A simple and direct method of estimating ferrocyanide by standard lead nitrate with diphenylcarbazone as an internal indicator has been described. The results are accurate and compared favorably with those obtained by other classical procedures.