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Volume 12 (1986)
- Issue 6 Pages 627-
- Issue 5 Pages 499-
- Issue 4 Pages 375-
- Issue 3 Pages 251-
- Issue 2 Pages 127-
- Issue 1 Pages 1-
Predecessor
Volume 12, Issue 3
Displaying 1-16 of 16 articles from this issue
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Ryuzo Ito, Yoshiro Inoue, Syuji Saeki, Tadashi Hirota, Koji Nagatomi1986 Volume 12 Issue 3 Pages 251-258
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSBénard convection with several kinds of initial wave number is created by imposing thermal disturbances from the outside. The stability of the convection patterns which then appear is investigated and the wave numbers at steady state are measured. The rule that controls the change of steady wave number caused by the variance of Reyleigh number is also studied.View full abstractDownload PDF (6153K) -
Ryuzo Ito, Yoshiro Inoue, Katsuya Ujita1986 Volume 12 Issue 3 Pages 259-266
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe shape of roll-cells in Bénard convection is dominated by many factors. The process of change in their width is affected seriously by the existence of the side wall in a container and changes in the two-dimensional convection pattern such as cross-roll instability and zigzag-roll instability.
To investigate the stability of roll-cells in the absence of these effects, in this study we developed Bénard convection in an annular vessel of equal depth and width a radius ten times the depth, and examined the relationship between the convection pattern, the width of the rollcell and the Rayleigh number. The roll-cell patterns in the annular vessel are more stable those that in the square vessel. The roll-cells at steady state can have a large extent of wave numbers, and can exist stably even at high Rayleigh numbers of more than 100 times the critical Rayleigh number.View full abstractDownload PDF (5959K) -
Yoshiro Inoue, Ryuzo Ito1986 Volume 12 Issue 3 Pages 267-272
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSBénard convection is a phenomenon in which hydrodynamic effects interact with thermodynamic ones. The onset condition of convection derived by the linear stability theory is reexamined from both the hydrodynamic and the thermodynamic points of view. The entropy and the entropy production rate of the Bénard cell in a steady cellular convection state are calculated, and the relationship between the cellular structure and the entropy is investigated.View full abstractDownload PDF (935K) -
Masato Tanaka, Takami Morishima, Hiroyoshi Yoshimura1986 Volume 12 Issue 3 Pages 273-279
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA study of the deposition of solid particles on the walls of a reactor and draft tube was performed.
As model solid particles, polystyrene beads were adopted. By installing a draft tube instead of baffle plates, the amounts deposited on the reactor wall were greatly reduced. However, the amounts deposited on the outer wall of the draft tube became larger than those on the reactor wall and much larger than those on the inner wall of the draft tube. With increasing impeller speed the amounts deposited on the walls of reactor and draft tube increased, reaching a maximum at Reynolds number of 1×104 to 1.5×104, and then decreased. The total deposited amounts became minimal at an impeller height of H=0.5 and a draft tube length of Hd = 0.59.View full abstractDownload PDF (1067K) -
Michio Mineshima, Tetsuzo Agishi, Kazuo Ota, Kiyotaka Sakai1986 Volume 12 Issue 3 Pages 280-286
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSDevelopment of donation plasmapheresis is urgent in Japan, where 25 % of the world's plasma fractions are consumed at present. In the present work, performance of a newly introduced disk-type membrane separator for donation plasmapheresis which was primarily devised for plasma exchange treatment for auto-immune disease patients was evaluated in constant-pressure experiments using bovine blood.
From the results of these experiments over a wide range of wall shear rate (γω) and hematocrit (Hb), the following equation for volumetric flux through membrane (Jv) at radial distance from center (r) was obtained :
Jv (r) =1.56×10-9γω (r) /r1/3ln (1.48/Hb (r))
Design of a plasma separator to satisfy the necessary condition (more than 4 × 10-4m3 plasma collection for 1800 s) was examined, using the above equation. Consequently, the optimum length, the inner diameter of the module, and the thickness and numbers of blood layers were determined for 0.15 m2 of membrane surface area.View full abstractDownload PDF (987K) -
Kazumi Sato, Norifumi Maeda, Zenya Yoshino1986 Volume 12 Issue 3 Pages 287-293
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe effects of Reynolds number, configuration of impeller and vessel, ratio of impeller to vessel size, liquid depth and rotational direction of each impeller on power consumption of twin impellers in rectangular stirred vessels were examined experimentally.
Power consumption in the turbulent region was closely related to the degree of tangential flow to circulation flow formed by each impeller.
The flow pattern in a rectangular vessel with twin disc turbines varied with geometrical conditions from a pattern mainly composed of tangential flow to a pattern mainly composed of circulation flow. The power number in this system changed in the range of 3 to 6 corresponding to the change of flow pattern.
In the system of twin pitched-blade turbines, circulation flow was predominant. Therefore, interactions between impellers were weak and the power number remained nearly constant.View full abstractDownload PDF (5069K) -
Niichi Hayashi, Masashi Iwata, Susumu Umemura, Toshiro Murase, Mompei ...1986 Volume 12 Issue 3 Pages 294-300
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe mechanical strength of waterworks sludge, which was aggregated by organic polymer flocculants and dewatered by gravitation, was measured by a rod penetration method. It was found that the results of a rod penetration test and a parallel-plate compression test showed a good mutual relation. Optimum polymer dosage was found at the point of minimum dimensionless rod penetration depth. The relation between rod pressure, σ, and apparent void ratio, e*, of aggregates under the rod was represented empirically by Terzaghi-Peck's form, not depending on rod diameter and the amount of sample solids. The apparent compression index, Cc*, which is a tangent of e* vs. ln σ plots, can be used as a measure of the strength of aggregates.View full abstractDownload PDF (1117K) -
Eiichi Kunugita, Hirokazu Nishitani, Yoshinori Kutsuwa1986 Volume 12 Issue 3 Pages 301-306
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe flexibility of a process system represented by the linear model is defined by a feasible region in the space of the main system outputs or in the space of uncertain parameters related to demand for the outputs. In the present work, a method to approximate the feasible region and to measure the flexibility was developed. The method is composed of locating the boundary points of the feasible region by using linear programming and making up the convex hull of these points. The feasible region is represented by a polytope. The largest hypersphere inscribed in the polytope can be used as a measure of the extent of flexibility. As an illustration, the feasible regions of an existing steam and power system were obtained and the flexibility of the system was studied.View full abstractDownload PDF (991K) -
Kenji Takeshita, Asashi Kitamoto, Yoichi Takashima1986 Volume 12 Issue 3 Pages 307-314
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe isotope separation performance of carbon-13 with exchange reaction between CO2 and carbamic acid was studied and some factors for the counter-current column were studied for improving the overall performance.
The working fluid for the experiments was a solution of DNBA, (C4H9) 2NH, and n-octane mixture.
The rate-controlling step of 13C transfer at temperatures higher than 10°C was the exchange reaction between carbamic acid and CO2 dissolved by physical absorption. The capacity coefficient of 13C transfer between gas and liquid in the counter-current column was successfully related to the product of three factors : the concentration of carbamic acid, the concentration of CO2 dissolved by physical absorption and the liquid holdup of the column.
The liquid holdup was also an important factor. As the holdup increased, the isotope exchange rate and the overall separation factor of the column increased. However, the transient time to equilibrium was much longer.View full abstractDownload PDF (1178K) -
Jihong Wu, Masaki Funakoshi, Hakuai Inoue1986 Volume 12 Issue 3 Pages 315-319
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSAcetoxylation of benzene in acetic acid, using Pd (OAc) 2-KNO3 as catalysts, was carried out in ampoule tubes. In this catalytic reaction the main product was phenylacetate, with nitrobenzene as by-product. It was found that the selectivity of the reaction was strongly affected by the concentration of benzene. The production rates of phenylacetate and nitrobenzene were found to be first-order with respect to benzene. At a fixed benzene concentration these rates depended only on the initial concentration of Pd (OAc) 2, while the maximum yields of these products were determined only by the amounts of KNO3 added, independent of Pd (OAc) 2. The rates were analyzed quantitatively and the rate equations were derived. The apparent activation energies were 129 KJ/mol and 140 KJ/mol respectively. The relationships between the maximum yields of phenylacetate and nitrobenzene and the catalyst concentrations were also expressed by experimental equations. The highest yield of phenylacetate normalized by mole of palladium added was found to be about 32.View full abstractDownload PDF (830K) -
Kazuhisa Ohtaguchi, Mitsuya Ishihara, Ichiro Inoue1986 Volume 12 Issue 3 Pages 320-326
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSEffects of initial lactose concentration and the size and cellular function of inoculum on growth and lactic acid production of Streptococcus thermophilus were investigated in a series of batch culture experiments. The change in cellular function of inoculum was established by regulating the culture age of the inoculum grown in a batch preculture vessel.
Results showed that lactose concentration and inoculum age exerted a great influence on batch productions, though no substantial effects were observed by variation of the size of the transferred inoculum. The highest concentration of biomass of about 0.78 kg/m3 was attained at low substrate concentration with an inoculum of age 6 h, whilst the highest concentration of acid of about 10.9 kg/m3 was observed with an inoculum of age 24.5 h. Growth and production of acid in batch culture were related substrate concentration and cellular function of inoculum with synthesized parameters.View full abstractDownload PDF (1401K) -
Teruo Takahashi, Yoshiro Kitamura, Shuji Okagaki, Takashi Korenaga1986 Volume 12 Issue 3 Pages 327-333
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe effect of organic substance in water phase on the coalescence rate of water-in-kerosene emulsions stabilized by Span 80 was experimentally investigated. Coalescence rates of droplets in the emulsion were determined by measuring the change of droplet size with time. It was found that the presence of monohydric alcohols in water phase accelerated the coalescence of emulsion droplets, and also that the coalescence rate increased with increasing both the concentration of alcohols and the carbon chain length of monohydric alcohols. The adsorption of Span 80 at the water/kerosene interface was determined by measuring interfacial tensions as a function of concentration of surfactant. The dependence of the coalescence rate on the presence of alcohols was confirmed to be due to the reduction of the surfactant's adsorption.View full abstractDownload PDF (1069K) -
Norio Arai, Yoshihiko Ninomiya, Masanobu Hasatani1986 Volume 12 Issue 3 Pages 334-341
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe fractional conversion of fuel-N into NOx in a diffusion flame of fuel oil was investigated experimentally by means of a two-staged modeled combustor : a tubular-flow thermal decomposer was placed just before a combustion chamber in which a diffusion flame was stabilized. Mixed gas of O2 and He was fed as an oxidizer so as not to form any thermal NOx. Conversion data were gathered using kerosene as a base fuel oil, and pyridine, quinoline and α-picoline as a fuel-N source.
The present fractional conversion data have much smaller values than those predicted from Fenimore's semi-theoretical equation, particularly at lower fuel-N concentrations. It was also recognized from comparisons of the present data with previous data as well as Fenimore's equation that preliminary gas-phase pyrolysis in the thermal decomposer enhances the conversion rate of fuel-N into N2 gas in the fuel-rich zone of a diffusion flame.View full abstractDownload PDF (1328K) -
Kaoru Soyama, Masayuki Gotoh, Shigeru Matsumoto, Mutsumi Suzuki1986 Volume 12 Issue 3 Pages 342-348
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSA new type of Laplace transform is defined in which the direction of the integral with respect to time is reversed. The great advantage of this integral transform technique is that the transform of a function of time can be sequentially evaluated from the series of observed data. Based on this technique, an estimation method for system parameters is developed which is available for on-line identification. The proposed method can be applied to both lumped and distributed parameter systems, and also to slow time-varying systems. Batch fermentation and one-dimensional heat conduction are used to demonstrate the application of the present algorithm.View full abstractDownload PDF (874K) -
Shigeru Itsuno, Yoshio Iwai, Yasuhiko Arai1986 Volume 12 Issue 3 Pages 349-353
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSThe mass-fraction Henry's constants for twelve hydrocarbon gases (i-butane, n-butane, 2, 2-dimethylbutane, n-hexane, n-octane, n-decane, cyclohexane, 1, 3-butadiene, benzene, toluene, ethylbenzene and mesitylene) were obtained in styrene-butadiene copolymers in the region from 150 to 225°C under atmospheric pressure by gas chromatography. Three types of copolymer having 30, 45 and 77 mass % of styrene were adopted.
The perturbed-hard-chain theory was applied to correlate the mass-fraction Henry's constants of hydrocarbon gases in styrene-butadiene copolymers. The calculated results are in good agreement with the experimental data. It was found that the interaction parameter between solute and copolymer can be evaluated by a function of temperature with the interaction parameters between a solute and homopolymers.View full abstractDownload PDF (741K) -
Kunihiro Kitano, Shigeo Chiba, Yoneshiro Tazaki, Senji Honma, Midori Y ...1986 Volume 12 Issue 3 Pages 354-374
Published: May 10, 1986
Released on J-STAGE: November 12, 2009
JOURNAL FREE ACCESSDownload PDF (3387K)
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