JOURNAL OF CHEMICAL ENGINEERING OF JAPAN
Print ISSN : 0021-9592
Volume 8 , Issue 6
Showing 1-19 articles out of 19 articles from the selected issue
  • HAKARU MITSUTAKE, MASASHI SAKAI
    1975 Volume 8 Issue 6 Pages 435-439
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    The activity coefficient of ethanol-water solution, the concentration of which is determined by measurement of the change of height and surface area of curvature of its meniscus, was obtained by unsteady static means using Stefan''s vertical capillary tube especially at room temperature where equivalent vapor pressure is low.
    The activity coefficient was calculated by Eq. (12) deduced from Stefan-Maxwell equation (1) and its value agreed with that obtained by distillation in steady state.
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  • TSUYOSHI MUNAKATA, KAZUNORI WATANABE, KENJIRO MIYASHITA
    1975 Volume 8 Issue 6 Pages 440-444
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    Minimum wetting rates were obtained for glass and stainless steel tubes by using glycerolwater mixtures of various compositions. Results show that the wetting behavior of the liquid in the range of high viscosity is sharply different from what has been reported previously by several workers.
    To account for this phenomenon, the model proposed to date, in which only the inertia force is taken into account, is modified for addition of the viscous force. As a result, the following semiempirical equation is obtained:
    K(Γ/μ)2/3+2•35/3/15(Γ/μ)5/3=A(ρσ34g)1/3
    where K and A are the numerical constants to be evaluated appropriately.
    It has been demonstrated that the proposed equation gives good correlation in a wide range of (ρσ34g).
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  • TAKAO KOKUGAN, TSUYOSHI KINOSHITA, NOBUYUKI TANIGUCHI, MASARU SHIMIZU
    1975 Volume 8 Issue 6 Pages 445-450
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    To obtain the relation between mean natural convection and experimental conditions in a heated vertical open tube consisting of heated and calming sections, experimental and theoretical studies were performed. Correlations between Grashof number (Gr) and Reynolds number (Re) were derived by setting up a mechanical energy balance in the tube. The following equation was obtained semi-empirically in the present experimental conditions.
    Gr0=6.3•Re02+32•(LH+L0)/D•Re0
    Experimental results were replotted and were in qualitative agreement with the relations between dimensionless tube length and dimensionless flow rate which were solved by Davis et al. by the finite difference method. It was found that the equation obtained semi-empirically was suitable for relations between mean natural convection and operating conditions. It was confirmed that the effects of calming section length on the hydraulic relations between Gr and Re are similar to those on the heat transfer relations between Rayleigh number and Nusselt number reported by Dyer.
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  • TAKESHI KATAOKA, HIROYUKI YOSHIDA
    1975 Volume 8 Issue 6 Pages 451-456
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    Ion exchange between different ions in resin phase was analyzed by applying a model in which the changes of resin diameter and ion diffusivity with the progress of ion exchange were considered simultaneously in addition to the effect of an electric field. Numerical results were applied to systems which exhibit larger and smaller volume changes, respectively. The present model may be used for the case when a large resin volume change occurs, while the simple Nernst-Planck model is applicable to the case of a small-volume change system.
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  • TAKESHI FURUTA, TAKAO JIMBO, MORIO OKAZAKI, RYOZO TOEI
    1975 Volume 8 Issue 6 Pages 456-462
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    The average and local mass transfer coefficients for a rotating sphere in an axial stream were measured by an electrochemical method over a range of Rer from 103 to 5 × 104 and four kinds of Rer. Fifteen isolated electrodes were used to obtain the local mass transfer rate. The convective diffusion equation for laminar boundary layer on the sphere was solved by the Lighthill transformation on the basis of numerically calculated shear stress distribution by the series expansion method. The numerical results, using the measured mainstream velocity, were in good agreement with the experimental ones over the laminar boundary layer region except very near the separation point.
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  • TAKAO MIYATA, FUMIYUKI NAKASHIO
    1975 Volume 8 Issue 6 Pages 463-467
    Published: December 31, 1975
    Released: March 28, 2006
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    The bulk polymerization of styrene was carried out under ultrasonic irradiation. The effects of power input and frequency of ultrasonic waves on the polymerization rate and the molecular weight distribution of polymer were studied. The mechanism of polymerization was not affected by ultrasound, but the overall rate constant decreased linearly with increase of net ultrasonic energy, and the average molecular weight of polymer slightly increased with ultrasonic irradiation. These results are caused by the accelaration of termination reaction and/or the decrease of initiator efficiency with ultrasonic irradiation.
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  • TAKAO MIYATA, FUMIYUKI NAKASHIO
    1975 Volume 8 Issue 6 Pages 468-472
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    The bulk copolymerization of styrene and acrylonitrile with 2, 2''-azobisisobutyronitrile as the initiator, was carried out under ultrasonic irradiation. The effects of ultrasonic waves on the copolymerization rate and the average molecular weight of polymer were studied. It was found that the kinetic scheme of copolymerization was not affected by ultrasound, but that the kintic parameters were affected by ultrasonic waves except for the rate constant of acrylonitrile homopolymerization, δ''B, and reactivity ratios, rA and rB. The rate constant of styrene homopolymerization, δ''A, andØ value increased with ultrasonic irradiation, although initiator efficiency decreased slightly with ultrasonic irradiation. It is suggested from these results that ultrasonic waves increased the recombination of two free radicals.
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  • KUNIO KATAOKA, HIDEKI DOI, TAKAO KONGO, MICHIO FUTAGAWA
    1975 Volume 8 Issue 6 Pages 472-476
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    Mixing properties of Taylor vortex flow with small constant axial flow rates were investigated in an annulus between two concentric rotating cylinders by injecting a salt-solution tracer or by suspending small soluble particles. Longitudinal intermixing of fluid elements between the neighboring vortices was examined by a method of two-point measurement. Circumferential mixing in each cellular vortex was also evaluated by comparing two successive time variations of concentration at a certain point in the case of no axial flow. The modes of flow were mapped in terms of Taylor number and Reynolds number. This vortex flow has been found to be an ideal plug-flow for the range of 51.4<Ta<640 and 0<Re<90. Each cellular vortex marches through the annulus in single file without intermixing over the cell boundary, whereas the toroidal motion of fluid elements causes highly effective radial mixing in the vortex. When Taylor number exceeds 640, the plug flow cannot be maintained owing to the occurrence of longitudinal intermixing over the cell boundary, which is attributable to the transition from singly to doubly periodic flow.
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  • MASARU ISHIDA, TAKASHI SHIRAI
    1975 Volume 8 Issue 6 Pages 477-481
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
    In a fluidized bed with a draft tube, solid particles can be smoothly circulated by keeping the inner zone within the draft tube in a fluidized condition and the outer annular zone between the draft tube and the column wall in a fixed-bed condition. The size of the opening under the draft tube was found to be quite important in achieving smooth and steady circulation. When it was too small, solids circulation was retarded or entirely stopped.
    To elucidate the driving force of this solids circulation, a fluidized bed and a fixed bed were connected through an opening and the equilibrium conditions between the heights of both beds were examined experimentally and theoretically. The concept of the equilibrium bed heights proposed in this study can be applied not only to problems of the circulation of solid particles but also to similar problems in the solids handling, such as the elevation of solids.
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  • EIICHI ONUMA
    1975 Volume 8 Issue 6 Pages 482-487
    Published: December 31, 1975
    Released: March 28, 2006
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    As a first step towards a more reasonable description of the steady-state characteristics of closed-circuit grinding systems, a grinding system with a semi-ideal classifier-whose performance curve consists of the partition phenomenon towards the coarse products and ideal classification in other respects-is analyzed. The aim of this analysis is to clarify the effects of classifier performance on the steady-state flow-rate and also on the particle size distribution of fine products. Based on the above analysis, the relationship between the total flow-rate of materials through the mill and the steady-state flow rate or the particle size distribution of the fine products is estimated and compared with experience in industrial-scale ball mill systems. Based on all the above investigations, some principles in the system design of closed-circuit grinding processes are suggested.
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  • KUNIO ATSUMI, TETSUO AKIYAMA
    1975 Volume 8 Issue 6 Pages 487-492
    Published: December 31, 1975
    Released: March 28, 2006
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    Continuity equations and Darcy''s law are utilized to obtain a basic equation for cake filtration. The boundary condition at the moving surface is newly derived, and the cake filtration is formulated in a Stefan problem.
    A similarity variable is introduced to transform the governing equation into an ordinary one, which in turn is solved numerically. The moment method is shown to offer good initial values to start the numerical computation.
    Satisfactory agreement is observed between experimental data of Shirato et al. and computed values of some physical properties.
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  • KATSUJI NODA, KURAJI SATO, KOICHI NAGATSUKA, KIYOHARU ISHIDA
    1975 Volume 8 Issue 6 Pages 492-493
    Published: December 31, 1975
    Released: March 28, 2006
    JOURNALS FREE ACCESS
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  • ZDZISLAW M. KURTYKA
    1975 Volume 8 Issue 6 Pages 494-495
    Published: December 31, 1975
    Released: March 28, 2006
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  • TAKASHI KATAYAMA, KAZUNARI OHGAKI
    1975 Volume 8 Issue 6 Pages 495-497
    Published: December 31, 1975
    Released: March 28, 2006
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  • TATSUO KANKI, SATORU IUCHI
    1975 Volume 8 Issue 6 Pages 497-500
    Published: December 31, 1975
    Released: March 28, 2006
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  • YUJI SANO, SINRI TAMAOKA
    1975 Volume 8 Issue 6 Pages 500-504
    Published: December 31, 1975
    Released: March 28, 2006
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  • SENZO HAMAI, MASASHI MITANP
    1975 Volume 8 Issue 6 Pages 504-506
    Published: December 31, 1975
    Released: March 28, 2006
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  • TSUNEO SEKIZAWA, HIROSHI KUBOTA
    1975 Volume 8 Issue 6 Pages 507-508
    Published: December 31, 1975
    Released: March 28, 2006
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  • KAZUNORI WATANABE, TSUYOSHI MUNAKATA
    1975 Volume 8 Issue 6 Pages 509
    Published: December 31, 1975
    Released: March 28, 2006
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