Showing papers by "Nagoya Institute of Technology published in 1972"
01 Jan 1972
40 citations
TL;DR: In this article, it was suggested that the glass structure changed sharply at a composition between As 2 S 2.6 and As 2S 2.7 ; glass-glass phase separation occurred when the sulfur content was lower than the As 2 s 2.67 composition.
Abstract: AsS compositions with varying sulfur content, melted in evacuated sealed tubes, were subjected to X-ray powder diffraction, density measurement, micro-Vickers hardness test, differential thermal analysis, electron microscopic observation and electron probe X-ray microanalysis. The glass-forming region has been determined. Structure of glasses has been discussed on the basis of the results of the measurements. It was suggested that the glass structure changed sharply at a composition between As 2 S 2.6 and As 2 S 2.7 ; glass-glass phase separation occurred when the sulfur content was lower than the As 2 S 2.67 composition.
29 citations
17 citations
TL;DR: In this article, the sensitization effect of tertiary amines on the photopolymerization of methyl methacrylate was studied and a free-radical mechanism was confirmed by the tacticity of polymer, the retarding effect of hydroquinone, and the copolymer composition with styrene.
Abstract: The sensitization effect of tertiary amines on the photopolymerization of methyl methacrylate was studied. N,N-Dimethylbenzylamine, triethylamine, and N,N-dimethylaniline increased the rate of polymerization in this order, but pyridine did not show any effect. A free-radical mechanism was confirmed by the tacticity of polymer, the retarding effect of hydroquinone, and the copolymer composition with styrene. On the basis of the detailed kinetics of the sensitized polymerization and the ultraviolet spectra of the reaction mixtures, a sensitization mechanism is proposed, in which the excited monomer and the amine form a complex and generate an initiating radical.
14 citations
11 citations
TL;DR: Theoretical considerations on the optimum ligand concentration and the optimum composition of the ligand buffer are followed by the determination of zinc in cadmium as an example.
8 citations
6 citations
TL;DR: In this article, the chain transfer constant of the polymethyl methacrylate radical for N,N-dimethylaniline was determined in two solvents, benzene and dimethyl phthalate.
Abstract: The chain transfer constant of the polymethyl methacrylate radical for N,N-dimethylaniline was determined in two solvents, benzene and dimethyl phthalate. Plots were made using1/Pn=kt°Rp/kp 2[M]2η + CS1 [S1]/[M] + CS2 [S2]/[M] +CM where η=viscosity of monomer-solvents mixture, kt°=rate coefficient of termination when η=1 cP, S1=benzene or dimethyl phthalate, S2=N,N-dimethylaniline, and other symbols have their usual meanings. The plots agreed well for the two solvents. If the plots were made without considering the viscosity term, two separate lines resulted for the two solvents. Thus it is essential to consider the viscosity of the polymerizing system in the analysis of chain transfer reactions when the termination reaction is diffusion-controlled and the viscosities of the monomer and solvent differ markedly.
5 citations
TL;DR: In this paper, a tensammetric wave of organic reagents such as oxine and alizarin complexone (ALC) was used for complexometric titration.
Abstract: A new method for the end-point detection in complexometric titration using a tensammetric wave of organic reagents such as oxine and alizarin complexone (ALC) was studied. The tensammetric wave of these reagents disappears by their chelate formation and reappears by the liberation of free indicator during the exchange reaction between indicator chelate and EDTA. This mechanism is utilized for the end-point detection in complexometric titration of metals. Since the sensitivity of tensammetric wave is extremely high, very sharp end-point can be obtained for the titration of metals even in the concentration of 10−5M.
4 citations
TL;DR: In this paper, a simple model for describing the time dependence of the transient electric current in a glass was presented, which states that on the current versus time curve there is a region in which the current I changes with time t exponentially, as ln I0/I = t/τ, and the constants I0 and τ, defined respectively as an initial current and a time constant, should follow the identical temperature dependences to yield the activation energy for conduction.
Abstract: A simple model was presented for describing the time dependence of the transient electric current in a glass. The model states that on the current versus time curve there is a region in which the current I changes with time t exponentially, as ln I0/I = t/τ, and the constants I0 and τ, defined respectively as an initial current and a time constant, should follow the identical temperature dependences to yield the activation energy for conduction. The model was checked by electrical measurements on a lithium disilicate glass made at an applied field of about 50 V/cm or less and in the temperature range of 50–150°C, and the activation energy for conduction was deduced to be 17.1 kcal/mol. Disagreement between this and the literature-cited values of about 14 kcal/mol was discussed.
4 citations
TL;DR: In order to study the thiyl radical, SS′-Diphenyldithiocarbonate (DTC) was used as a photo-sensitizer of radical polymerization of styrene, methyl methacrylate and acrylonitrile, and the rate of decomposition of DTC was also studied.
Abstract: In order to study the thiyl radical, SS′-Diphenyldithiocarbonate (DTC) was used as a photo-sensitizer of radical polymerization of styrene, methyl methacrylate and acrylonitrile, and the rate of decomposition of DTC was also studied DTC was decomposed into phenyl thiyl radical and carbon monoxide by ultra-violet light, but it was not decomposed by heat at 60°C The thiyl radical which derived from the photo-dissociation of DTC initiated the radical polymerization, and also worked as a terminator or a chain transfer agent
The kinetic of photo-sensitized polymerization by DTC coincided with the ordinary radical polymerization mechanism
Um das Thiylradikal zu untersuchen, wurde SS′-Diphenyldithiocarbonat (DTC) als Photosensibilisator der Radikalpolymerisationen von Styrol, Methylmethacrylat und Acrylnitril verwendet; dabei wurde auch die Zersetzungsgeschwindigkeit von DTC bestimmt Durch ultraviolettes Licht wurde DTC in das Phenylthiyl-Radikal und Kohlenoxid gespalten, hingegen wurde es durch Warme bei 60°C nicht zersetzt Das Thiyl-Radikal, das durch die Photodissoziation von DTC entsteht, initiert die Radikalpolymerisation; auserdem wirkt es als ein Agens der Kettenubertragung oder des Kettenabbruchs
Die Kinetik der durch DTC photosensibilisierten Polymerisation stimmt mit dem normalen Mechanismus der Radikalpolymerisation uberein
TL;DR: In this article, the theoretical calculation of melt spinning of metals was carried out by applying the theory for the polymer melt spinning and it was confirmed that the results of calculation agrees approximately with the experimental ones.
Abstract: The theoretical calculation of melt spinning of metals was carried out by applying the theory for the polymer melt spinning and it was confirmed that the results of calculation agrees approximately with the experimental ones.The resulted equations are as follows;a) Breaking length by filament weight (lc)b) Breaking length by jet flow (Z*)c) Changes of diameter and speed by filament fallingd) Coagulating length from nozzle (Zl)e) Average temperature of filament after coagulation Where, α: surface tention, ρ: density, R0: radius of nozzle, g: acceleration of gravity, δ0: amplitute on vibration, d0: diameter of nozzle, Hf: latent heat, P: pressure, V: velocity at Z point, V0: ejection speed, Tm: temp. of metal, T*: surrounding temperature, T0: coagulating temperature, Cp: specific heat of metal, A0: area of nozzle The next relation is necessary for good spinning of metal filament.
TL;DR: In this paper, an analytical model for predicting the fractional conversion of catalytic reaction in gaseous fluidized bed reactor is developed, and data calculated from this model are compared with experimental data obtained by the other investigators.
Abstract: Simplifying a model previously proposed by the authors, an analytical model for predicting the fractional conversion of catalytic reaction in gaseous fluidized bed reactor is developed. Concerning the fractional conversion, data calculated from this model are compared with experimental data obtained by the other investigators. Effects of cross-flow rate of gas between bubbles and the surrounding dense phase on the fractional conversion are discussed in terms of sensibility coefficients.
TL;DR: In this article, a general treatment of failure mechanism of particulate composites in which aggregate or particles are dispersed into a brittle matrix, such as cement concrete, is given. But the failure mechanism is not considered in this paper, and the experimental results are examined on 51 composites made with seven types of aggregates and two types of matrices.
TL;DR: In this article, the modified damage constant, KL = (1/Li2 − 1/LO 2).φ−1, is obtained from the drop rate of the photo-current at 1.0 μm monochromatic light irradiation, where the minority carrier diffusion length in the bulk region before γ-irradiation, L0, is estimated by fitting the observed spectral response curve to those calculated with the diffusion length as parameter.
Abstract: The modified damage constant, KL = (1/Li2 – 1/LO 2).φ−1, is obtained from the drop rate of the photo- current at 1.0 μm monochromatic light irradiation, where the minority carrier diffusion length in the bulk region before γ-irradiation, L0 , is estimated by fitting the observed spectral response curve to those calculated with the diffusion length as parameter. The values Li and φ represent the minority carrier diffusion length after γ-irradiation, and the total flux of incident γ-ray photons, respectively. When N/P-type cells are contaminated with Cu, the values of KL by about one order of magnitude compared with non-doped cells, while those of the P/N-type cell contaminated with either Cu or Ni ane only slightly smaller than when not doped. The KL values of the pulled (C.Z) bulk P/N-type cell are about 1/2 those of the floating zone (F.Z) bulk cell. The curves of KL of the non-doped F-Z and C-Z bulk P/N-type cell vs. total dosage begin to decrease from a point below 1016 photons/cm2 total dose. Also, th...
TL;DR: In this paper, the effect of free carboxylic acid in polyester films on the uptake of stannous chloride was studied and the following results were obtained: the saponification rate of polyester film with alkali solution is given by the following equation.
Abstract: In order to improve the activity of polyester film for tin, alkali saponification was employed and the effect of free carboxylic acid in film on the uptake of stannous chloride was studied. The following results were obtained.a) The saponification rate of polyester film with alkali solution is given by the following equation.dX/dt=kA X: dissolved polymer (g)k: rate constantA: surface area of filmb) The production of free carboxylic acid in film by alkali saponification is accelerated with reaction time until it ceases after certain interval.c) The stannous chloride uptake increases with the free carboxylic acid content in the film and the rate is described by Fick's equation. DSC annalysis suggested the occurrence of 2(-COO) + Sn++ type reaction at the early stage of the process.d) The copper uptake of the saponificated and SnCl2 treated film increases with the tin content and is proportional to time.
01 Jan 1972