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Volume 12, Issue 1
Displaying 1-19 of 19 articles from this issue
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EFFECT OF MOLECULAR WEIGHT ON DIFFUSION COEFFICIENTYAOMI KUMAGAI, HISAHIKO WATANABE, KAZUO MIYASAKA, Tosmo HATA1979 Volume 12 Issue 1 Pages 1-4
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSThe diffusion coefficients of polystyrene in polymer bulk were measured at 150°C by a radioactive tracer method over the range of molecular weight 1.10×105-1.80×106 for active polymer and 4.00×103-1.80×106 for inactive base polymer. The effects of molecular weight on diffusion coefficients are discussed from the experimental data obtained in this work. For one-component systems, it was disclosed that Bueche''s well-known relationship of diffusion coefficient, D, with viscosity, η, and temperature, T, i.e., Dη/T= constant, did not hold over the range of large molecular weight. As for binary systems, it was shown that diffusion coefficients at constant molecular weight of active polymer, Mp1, in inactive base polymer of molecular weight, Mp2, were proportional to M-1.7p2 when Mp2 was smaller than a critical molecular weight for diffusion, MD, beyond which diffusion coefficients were constant. It was also shown that diffusion coefficients were proportional to M-1.0p1 in the range of this work.View full abstractDownload PDF (262K) -
COMPARISON BETWEEN THE TWO POINT ELECTRIC PROBE METHOD AND THE PHOTOGRAPHIC METHODFUKUJI YAMASHITA, YOSHIRO MORI, SHIGEFUMI FUJITA1979 Volume 12 Issue 1 Pages 5-9
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSIn the bubble flow region of a two-dimensional bubble column, bubble sizes were measured by the two-point electric probe method and by the photographic method, and both the results are analysed and discussed.
Most bubbles in the bubble column are not spherical, but can be approximated by oblate ellipsoids. But the experimental results show that the volume-surface mean diameter equivalent to spherical bubbles, which is calculated by the analysis of Ueyama et al. for spherical bubbles with data obtained by the electric probe method, agrees fairly well with that obtained by the photographic method. The major axis of a rising bubble is not always horizontal, and the analysis shows that this fact may be the principal reason for the agreement.
A very simple method is presented to obtain the bubble size distribution curve from data of the electric probe method.View full abstractDownload PDF (419K) -
RYUZO ITO, KAORU TOMURA1979 Volume 12 Issue 1 Pages 10-13
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSFalling liquid films on inclined plates have been experimentally studied with special attention to the "calming zone", where the surface is mirror-like in the range of Re from 2500 to 6000.
Velocity profile by the hydrogen bubble method and film thickness by the pointer and gauge method were measured, and the film surface behavior was observed by laser beam reflection. Film flow in the calming zone is laminar with air drag at the air-liquid interface.View full abstractDownload PDF (405K) -
HAJIME NAKAMURA, AKIHIRO MATSUURA, JUMEI KIWAKI, NOBUO MATSUDA, SETSUR ...1979 Volume 12 Issue 1 Pages 14-18
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSNumerical solutions are presented for the flow and heat transfer problems of laminar forced convection for liquids in rectangular ducts by use of several correlative equations for viscosity-temperature as used in the studies of the circular tube, where the fully developed velocity and temperature fields, under the boundary conditions of axially uniform wall heat flux and peripherally uniform wall temperature, are assumed. The effects of viscosity variations on the profiles of velocity and temperature, the friction factor and the Nusselt number are summarized as follows: i) the velocity profile is strongly affected by the viscosity ratio based on the wall and cup mixing temperature (μw/μm), whereas the temperature profile is affected weakly, and ii) the relationship of f/fcp vs. μw/μm for various aspect ratios is in good agreement with that of the circular tube as reported by Shannon et al. and Deissler, in the region of μw/μm<10 where fcp is the friction factor for the case of constant viscosity. On the other hand, the relationship of Nu/Nucp vs. μw/μm is different from that of the circular tube, except in the region where μw/μm is closer to unity, and its difference is remarkable in a larger aspect ratio.View full abstractDownload PDF (355K) -
KATSUTOSHI INOUE, HIDEAKI OKUBO, FUMIYUKI NAKASHIO1979 Volume 12 Issue 1 Pages 19-23
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSThe extraction rate of copper with benzoylacetone was studied by a single-drop method, as basic research on extraction kinetics of metals by chelating agents. Specifically, a study of the extraction rate during drop formation was carried out.
A theoretical analysis of extraction kinetics accompanied by chemical reaction in the continuous phase was carried out for an (m, n)-th order reaction. The relationships between the extent of extraction during drop formation and drop formation time, concentrations of reactants in both phases and the reaction rate constant were clarified. The experimental results were correlated theoretically.
The good correspondence obtained indicates that the theoretical analysis described in this paper is useful for determination of kinetic mechanisms for the extraction of metals by chelating agents.View full abstractDownload PDF (395K) -
KEN TOYOKURA, KENJI TAWA, JUNJI UENO1979 Volume 12 Issue 1 Pages 24-28
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSReaction crystallization of sulfamic acid from urea and fuming sulfuric acid was studied in a continuous well-mixed crystallizer. In this work, growth rate and nucleation rate were correlated with retention time. Secondary nucleation obtained from two kinds of agitators was studied briefly on the basis of the collision model. On the other hand, reaction rate was represented by the pseudo-first order of urea concentration in a vessel and the correlation between reaction rate and retention time was also obtained. Because both reaction rate and crystallization rate were correlated with retention time, a new design method without use of correlative equations of supersaturation is proposed and a chart based on retention time is submitted.View full abstractDownload PDF (342K) -
MASAMOTO NAKAJIMA, SYOUJI HIROTA, KEISUKE FUKUI1979 Volume 12 Issue 1 Pages 29-33
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSGrowth and dissolution rates of a potash alum crystal have been measured at a constant temperature of 30°C. The diffusion theory for both growth and dissolution is discussed, based upon the experimental results. Based upon observations of the solution-crystal interfacial concentration for growth and dissolution, it is shown that the diffusion step in the growth process was second-order with respect to the driving force, and the presence of a separation step of solute or cluster from crystal lattice for the dissolution process is proposed because the interfacial concentration was not equal to saturated condition. Agreement between the dimensionless concentrations, which included the solution-crystal interfacial concentrations for growth or dissolution, related these phenomena and gave the relations among the transfer rate coefficients. And it was shown that the interfacial concentrations could be estimated even at a solution temperature other than 30°C by using the relations obtained at 30°C.
Therefore, the transfer coefficients of reaction and diffusion steps for the growth process can also be determined. The transfer coefficients of separation and diffusion steps for the dissolution process and interfacial concentration can also be calculated by measuring the overall rate coefficient for dissolution.View full abstractDownload PDF (374K) -
HIROMITSU SHIBUYA, KUNITARO KAWAZOE1979 Volume 12 Issue 1 Pages 33-37
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSA dynamic Wicke-Kallenbach method to obtain effective diffusivities is presented.
The method is carried out by performing curve-fitting between measured breakthrough curves and calculated ones obtained numerically by use of the Fourier inverse transform technique.
The major advantage of this transient method is that it is possible to determine effective diffusivities within a short measuring time.
The method is illustrated with experimental data for heavy water diffusing through activated carbon pellets. The values of effective diffusivity obtained for heavy water are reasonable ones and are in good agreement with those obtained previously using the breakthrough method.View full abstractDownload PDF (297K) -
KUNIO KATO, MITSUYOSHI MAENO, SEIICHI HASUKO1979 Volume 12 Issue 1 Pages 38-42
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSSeveral kinds of particles were fluidized with air in columns packed with open-end cylindrical screen packing and the lateral effective thermal conductivity was measured in the bed. The effective thermal conductivity in a packed fluidized bed was affected by the packing size, the minimum fluidization gas velocity, properties of fluidized particles, the void fraction of packing and the intensity of fluidization. The empirical equation for the lateral effective thermal conductivity for a packed fluidized bed was obtained.View full abstractDownload PDF (376K) -
SHIGEO CHIBA, HIROTOSHI TANIMOTO, HARUO KOBAYASHI, TADATOSHI CHIBA1979 Volume 12 Issue 1 Pages 43-45
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSTracer particle distributions produced after a single bubble passage through a 0.19 m i. d. gasfluidised bed were successfully measured and analysed, together with bubble characteristics, in order to determine the solid exchange coefficient between the bubble wake and the surrounding emulsion phase. Experimental values of the coefficient obtained decreased with increasing bubble diameters for a range of 0.02 to 0.09 m which could quite reasonably be explained by the simple model proposed in our previous paper.View full abstractDownload PDF (329K) -
MASARU ISHIDA, TAKASHI SHIRAI1979 Volume 12 Issue 1 Pages 46-50
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSThe velocity of solid particles flowing in an inclined open channel of which the bottom plate was covered with very rough sandpaper was measured for three kinds of particle.
Except for the region near the bottom plate, the velocity distribution normal to the bottom plate appeared to be linear. The velocity gradient in that region was almost independent of the thickness of the particle layer and increased as the slope of the channel became steep.
These observed velocity distributions were analyzed based on the variational principle, by which the velocity distribution could be obtained as the solution which minimized a certain integral consisting of several energy terms. It was found that such analysis could explain the main feature of the particle flow in an inclined channel, and the following relation between stress and rate of deformation was obtained.
τyz=kτy-kμy(dvz/dy)
It was also found that the critical inclination angle of the channel, which was anticipated by the analysis, corresponded to the angle of repose.View full abstractDownload PDF (349K) -
MOMPEI SHIRATO, TOSHIRO MURASE, KUNIO ATSUMI, TSUTOMU ARAGAKI, TETSUO ...1979 Volume 12 Issue 1 Pages 51-55
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSRecent developments in expression techniques may emphasize the need for a simpler method which is easily applicable to industrial data analyses, as well as a more accurate method of analysis which may lead us to a firmer understanding of the detailed mechanisms of entire expression processes. This paper is mainly concerned with the development of a simplified equation for constant-pressure expression of thickened semi-solid materials. The equation is based on the socalled modified Terzaghi equation and also on expression experiments, and may be viewed as a semi-theoretical one. Graphical methods for determining a newly defined value of the consolidation behavior index ν and the modified consolidation coefficient Ce are also presented.View full abstractDownload PDF (380K) -
SETSURO HIRAOKA, IKUHO YAMADA, KATSUMI MIZOGUCHI1979 Volume 12 Issue 1 Pages 56-62
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSA flow of non-Newtonian power law fluid in an agitated vessel with paddle impeller is obtained from numerical analysis based on a two dimensional flow model. The average shear rate obtained from the numerical solution coincides well with the experimental result for large-size impeller of d/D>0.7, and it is confirmed that the apparent viscosity is very useful in correlating not only power input but also shear stress distribution at vessel wall. The non-Newtonian viscosity profile in an agitated vessel depends remarkably on impeller dimension and scarcely at all on vessel dimension. This shows the usefulness of the concept of apparent viscosity proposed by Metzner et al. On the other hand, the velocity and vorticity profiles near the vessel wall can hardly be correlated with the characteristic velocity alone, because the flow pattern depends on the integrated effect of non-Newtonian viscosity in the flow region. These profiles show good similarity by using the appropriate correction factor.View full abstractDownload PDF (499K) -
HISAYOSHI MATSUYAMA, JUN''ICHI SHIOZAKI1979 Volume 12 Issue 1 Pages 62-64
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSDownload PDF (197K) -
EIZO SADA, TAKAAKI AMENO1979 Volume 12 Issue 1 Pages 64-66
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSDownload PDF (222K) -
RYUZO ITO, KAORU TOMURA1979 Volume 12 Issue 1 Pages 66-68
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSDownload PDF (197K) -
COCURRENT GAS-LIQUID FLOW WITH CIRCULATION IN GAS PHASEHARUO HIKITA, KOSAKU ISHIMI, NORIFUMI SOHDA1979 Volume 12 Issue 1 Pages 68-71
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSDownload PDF (310K) -
TAKEHIKO FURUSAWA, NOBUYUKI YAMADA, TAKASHI SENDO, DAIZO KUNII1979 Volume 12 Issue 1 Pages 71-73
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSDownload PDF (190K) -
KENJI KUBO, TOSHIRO ARATANI, AKIRA MISHIMA, TAKEO YANO1979 Volume 12 Issue 1 Pages 74-76
Published: February 20, 1979
Released on J-STAGE: April 03, 2006
JOURNAL FREE ACCESSDownload PDF (190K)
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