巻号一覧
34 巻, 4 号
選択された号の論文の17件中1～17を表示しています
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Thermodynamics, Physical Properties and Molecular Simulation
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FUMING CHEN, YUJI NAKA2001 年 34 巻 4 号 p. 466-471
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありAn equation for calculating activity coefficient has been proposed on the basis of Group Solubility Parameter (GSP) model. The group solubility parameter is divided into four dimensions (contributions) and their values were determined by regression to fit the VLE of 172 binary systems selected from the literature. For these binary systems, the total average calculated deviations by the model were 3.52% in y1 and 2.80% in P. The GSP model could be applied to predicting VLE of other binary or multi-component systems with good accuracy. Compared with other group contribution models, GSP model requires less adjustable parameters and their values can be easily determined.抄録全体を表示PDF形式でダウンロード (291K) -
KYUNG-HEE LIM, DUANE H. SMITH2001 年 34 巻 4 号 p. 513-522
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありExcess enthalpies (HE) for the binary n-butanol/water measured by isothermal flow calorimetry at 30 and 50°C, and nonionic amphiphile 2-butoxyethanol/water at 10 different temperatures (from 48.5 to 70°C) reported in the literature were analyzed for the determination of phase boundaries. HE exhibited S-shape behavior in the former system and U-shape behavior in the latter system. When the HE data in the single-phase were fitted by semi-empirical polynomials and critical-scaling equations, plots of specific HE vs. weight fraction provided more accurate fitting with fewer parameters than conventionally drawn molar HE vs. mole fraction plots. This was due to the enhanced symmetry of specific HE vs. weight fraction plots. Liquid-liquid equilibrium phase boundaries between the single- and two-phase regions were determined from HE. The phase boundary points were obtained as the intersections of the curve and the straight line, which describe the composition dependence of HE for the single- and two-phase regions, respectively. When Redlich-Kister (RK) and Padé polynomials were employed, the phase boundary points could be determined for the n-butanol/water but not for the 2-butoxyethanol/water. These results imply that correct phase boundaries may not be obtained with the semi-empirical polynomials when HE behavior is of the U-type. However, when the critical-scaling equations for HE of binary mixtures were used, the phase boundaries were obtained accurately, irrespective of the type of HE data.抄録全体を表示PDF形式でダウンロード (378K)
Transport Phenomena, Fluid Mechanics and Mixing
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YASUHIRO SUMI, MITSUO KAMIWANO2001 年 34 巻 4 号 p. 485-492
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありA new multistage impeller developed for mixing highly viscous fluids (0.1-10.0 Pa·s) in a stirred tank provides several advantages: excellent axial circulation flow, hardly any stagnant zones, and low power consumption. The impeller is composed of a vertical rotating shaft to which are attached, from top to bottom, a pair of two-bladed gate-impellers and one two-bladed paddle impeller. Four baffles are employed to accelerate the axial circulation flow in the tank. In this paper, the geometrical configuration of the multistage impeller is described, and its mixing characteristics for fluids of high viscousity—i.e. the power consumption, flow pattern, mixing time, circulation time, and mixing efficiency—are clarified. For comparison, the same characteristics were also examined in the stirred tanks using anchor, double-helical ribbon, and single-gate impellers. The results showed the multistage impeller to be superior to the other types in that the time required for complete mixing is relatively short and almost no stagnant zones are created. The relationship between the Reynolds and Nusselt numbers for the multistage impeller, as well as for single-gate and four-pitched paddle impellers, was clarified from the laminar to turbulent regions.抄録全体を表示PDF形式でダウンロード (3101K) -
YUAN-YUAN SU2001 年 34 巻 4 号 p. 531-539
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありIn this study we have performed the computation of eigenfunctions for determining various disturbance quantities in the inclined plane flow system. These disturbance quantities are subsequently inserted into disturbance energy equations to evaluate the amount of energy transfer at the interface and the free surface, and provide an insight into understanding instability mechanisms of multi-layer fluids onto an inclined plane. In energy analysis it is demonstrated that the dominant mechanisms occurring in the interfaces and the free surface are active in these instabilities. Specifically, it is suggested that the stability mechanism for the interface is associated with the coupling between the disturbance quantities and the base state velocity gradient.抄録全体を表示PDF形式でダウンロード (263K) -
YU-MIN YANG, SHAO-JEN YEH, CHIEN-KANG HSIUNG, CHEN-LUNG CHIEN, CHIEN-H ...2001 年 34 巻 4 号 p. 563-567
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありTwo catanionic surfactants were prepared in this work. Equilibrium and dynamic surface tensions and bubble volumes at detachment from a single orifice under constant-flow conditions were obtained experimentally for aqueous solutions of these two surfactants. While the catanionic surfactants were very effective in depressing the equilibrium surface tension, the dynamics surface tension data revealed that the surface relaxation for the catanionic surfactants was insignificant in the time period studied. The bubble formation results showed that the bubble volumes at detachment in aqueous solutions of the catanionic surfactants were hardly different from those in water. The Ruff model, which deals with bubble formation in pure liquids, and the modified Ruff model, which considers the dynamic surface tension effect, were used to estimate the bubble volumes at detachment in surfactant solutions. It was concluded that dynamic surface tension rather than equilibrium one is responsible for the bubble formation in the catanionic surfactant solutions.抄録全体を表示PDF形式でダウンロード (134K)
Catalysis, Kinetics and Reactor Design
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KAZUAKI YAMAGIWA, AKIRA ITO, YUSUKE KATO, MASANORI YOSHIDA, AKIRA OHKA ...2001 年 34 巻 4 号 p. 506-512
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありThe effects of liquid property on air entrainment and oxygen transfer characteristics of a plunging jet reactor are investigated in air-corn syrup solution system with changing the viscosity up to 40.5 mPa s. The effect of liquid property on air entrainment rate is divided into three regions. The transition points of the regions are represented with jet Reynolds number. The change in air entrainment rate with liquid property is discussed in relation to the change in jet surface disturbances. Empirical correlations are also presented to predict the air entrainment rate, gas holdup and oxygen transfer coefficient. The oxygen transfer performance of the reactor is superior to that of the conventional bubble columns and stirred tank reactors over the range of viscosity from about 1 to 40.5 mPa s. It is concluded that the plunging jet reactor is one of the most promising bioreactor treating a viscous fermentation broth.抄録全体を表示PDF形式でダウンロード (2361K) -
HIDEO TAJIMA, TAKASHI NIITSU, HAKUAI INOUE, MASATO M. ITO2001 年 34 巻 4 号 p. 553-557
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありWe quantitatively studied the effects of counter anions and solvents on the catalytic activity of thiazolium due to the completion of the formose reaction using the highly active immobilized catalyst. The relation between counter anions and the catalytic activity of thiazolium was represented very well by the electron donor constant and the basic constant of the anions. The solvent effect was represented by the individual solvent parameter. In this study, it was given an important information about the effects of the counter anion and the solvent on the reaction using an immobilized thiazolium catalyst.抄録全体を表示PDF形式でダウンロード (87K)
Separations
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KAZUAKI YAMAGIWA, MIKINORI KATOH, MASANORI YOSHIDA, AKIRA OHKAWA, HISA ...2001 年 34 巻 4 号 p. 479-484
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありThe effect of salt concentration on temperature-swing adsorption of nonionic surfactant Triton X-100 with poly(vinylmethylether) gel (PVMEG) was investigated with sodium salts of citrate, succinate, sulfate, hydrogen phosphate, chloride and nitrate. With increasing salt concentration, the amount of Triton X-100 adsorbed on PVMEG increased and the critical temperature range across which the adsorbed amount of Triton X-100 drastically changed shifted to the lower temperature side. The effects of salt type and concentration on temperature-swing adsorption process were evaluated in terms of effective adsorbed amount, midpoint temperature and temperature sensitivity. The effective adsorbed amount increased with increasing ionic strength up to a certain critical value depending on salt type, and then sharply decreased above the critical value. The dependency of midpoint temperature on ionic strength below the critical value was different from that above the critical value. The temperature sensitivity became minimum at ionic strength around the critical value .The critical ionic strength was found to be depend mainly on the valence of ion.抄録全体を表示PDF形式でダウンロード (4039K) -
HAMID REZA MORTAHEB, HITOSHI KOSUGE, KOICHI ASANO2001 年 34 巻 4 号 p. 493-500
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありAn experimental study on separation performance of sieve tray column in binary and ternary distillation is made under total reflux conditions with different tray specifications. Two different flow regimes are observed on the tray in different concentration regions for the ethanol-water, ethanol-benzene and ethanol-benzene-water systems. The liquid holdup in the foam regime is well correlated in terms of the weir height, free area and vapor phase Reynolds number. Although higher mass transfer rate is observed in the foam regime than that in the froth regime, the dimensionless volumetric vapor phase diffusion flux in the foam and froth regimes are well correlated in terms of the ratio of Froude to Weber number, free area and vapor phase Reynolds number.抄録全体を表示PDF形式でダウンロード (794K) -
KAZUHISA OKADA, YASUHIRO NISHII, SUSUMU NII, TAKUMI KINUGASA, KATSUROK ...2001 年 34 巻 4 号 p. 501-505
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありThe interfacial tensions of several solutions of reversed micellar systems used in lysozyme extraction were measured by drop weight and pendant drop methods. The organic phase was 2,2,4-trimethylpentane containing sodium bis(2-ethylhexyl)sulfosuccinate (AOT), and the aqueous phase was a solution of lysozyme and KCl, NaCl or CaCl2. The effects of salt concentration and salt type on the interfacial tension were studied. The hydration of cation associated with AOT affects interfacial properties to some extent. At the same ionic strength, the interfacial flexibility decreased with type of salt, NaCl > CaCl2 > KCl. This order corresponds to that of the cation's hydration number. Overall mass-transfer coefficients of lysozyme were also measured under various salt concentrations of three salt systems and were expressed by a single curve when plotted against interfacial tension.抄録全体を表示PDF形式でダウンロード (173K) -
KAZUHIRO YOSHIDA, YOSHIO HIRANO, HIRONORI FUJII, TOSHINORI TSURU, MASA ...2001 年 34 巻 4 号 p. 523-530
発行日: 2001年
公開日: 2002/04/26
ジャーナル フリーThree types of silica-zirconia membranes of different zirconia content were prepared by the sol-gel method to test their stability and H2 separation performance in hydrothermal conditions. Some silica-zirconia membranes were prepared by “steam-firing” in which firing was carried out in steamed air in order to increase the hydrothermal stability, and then tested in hydrothermal conditions. The activation energy of H2 and He permeation increased with increasing zirconia content, suggesting that the networks of silica-zirconia matrix were densified with increasing zirconia content. In the hydrothermal conditions, the activation energy of H2 and He permeation also increased, indicating clearly that silica-zirconia membranes were also densified by water vapor at high temperature. The pores for N2, Co2 and CH4 permeation decreased with the increasing zirconia content and vanished in the hydrothermal conditions, leaving some pinholes. Some silica-zirconia membranes were prepared by firing in steamed air in order to increase the hydrothermal stability. This method appeared to be effective to increase hydrothermal stability of the silica-zirconia membrane.抄録全体を表示PDF形式でダウンロード (341K) -
HIROTAKE KATAYAMA, MAKOTO MIZUTANI, SHINYA ISHIKAWA2001 年 34 巻 4 号 p. 558-562
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありPerformance of a horizontal column equipped with a rotary gauze-spring packing was evaluated. Through experiments conducted under atmospheric pressure at total reflux, using the cyclohexane-heptane system, separation efficiency, liquid holdup, and pressure drop were measured. Separation efficiency for the horizontal orientation (at 0 degrees) was somewhat better than at 5 degrees, and was expressed in terms of HETP, which ranged from 0.1 to 0.3 m when F-factor ranged from 0.05 to 0.32 m/s(kg/m3)1/2 for a speed of rotation of 100 to 600 rpm. Efficiency of the gauze-spring packing was somewhat inferior to that of the screw-brush packing described in our previous work. However, we found that pressure drop of the former can be reduced to one-tenth that of the latter, corresponding to one-hundredth that of a conventional packed column, such as a column having a Sulzer or McMahon packing.抄録全体を表示PDF形式でダウンロード (357K)
Particle Technology and Fluidization
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HIRONORI MINOSHIMA, KEIICHIRO MATSUSHIMA, HUA LIANG, KUNIO SHINOHARA2001 年 34 巻 4 号 p. 472-478
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありA simplified spray drying granulation model of a hollow granule from dispersed-system slurries was proposed in this work. The granulation mechanism was analyzed to replace with the solid-liquid separation by filtration. The factors that affect the diameter and the strength of the granule were investigated from the simulation based on the model.抄録全体を表示PDF形式でダウンロード (408K) -
QI LIU, MADHUMITA BHOWMICK RAY2001 年 34 巻 4 号 p. 540-548
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありCyclone dedusters are used in diverse contexts due to their many advantages over other primary collectors. The post cyclone (PoC) is a new secondary collector situated at the top of a conventional reverse flow cyclone, which utilizes the residual swirl available at the gas outlet (vortex finder) of the cyclone to capture a certain fraction of the escaped dust. In this paper, one design of PoC is tested where the particles are collected in a bleed flow drawn from the PoC. Subsequent to the particle separation, the lean bleed flow is recycled back to the inlet of the cyclone. The experiments conducted at different bleed flow rates and inlet velocity indicate an increase in overall efficiency of cyclone by 6% in average, and reduction in emission from the vortex finder by 5-9%.抄録全体を表示PDF形式でダウンロード (224K) -
EIICHI MINE, MIKIO KONNO2001 年 34 巻 4 号 p. 545-548
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありSeeded growth reactions of the hydrolysis and condensation of tetraethyl orthosilicate (TEOS) were performed at TEOS concentrations up to 1.2 mol/dm3. Reaction progress was followed by the in-situ measurements of pH and electric conductivity and by analyses of the final product. At a high TEOS concentration (1.2 mol/dm3), a large number of secondary particles were generated. As the TEOS concentration was reduced (0.4-0.8 mol/dm3), the secondary particles disappeared. A further reduction in the TEOS concentration (0.05-0.1 mol/dm3) led to the generation of secondary particles. From the results, the secondary particle generation could be explained by increased electrostatic repulsion forces. Further experiments performed with electrolytes confirmed this conclusion, where it was found that added electrolytes brought about the suppression of the secondary particles.抄録全体を表示PDF形式でダウンロード (128K)
Process Systems Engineering
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PAISAN KUTTISUPAKORN, MOHAMAD AZLAN HUSSAIN, JUTATAIP PETCHERDASK2001 年 34 巻 4 号 p. 453-465
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありReactor temperature control is very important as it affects chemical process operations and the product quality. Although PID controller, which is the linear controller and widely used in the chemical process industries, is able to control the temperature, the operating range is limited. Furthermore, its control performance when plant/model mismatches exist is not guaranteed. Recently, various advanced control techniques have been successfully applied to highly nonlinear systems. These include the Generic Model Control (GMC) and the Inverse-Model Control (IMC) techniques. However these methods still require reasonable and accurate process model and parameters, which are difficult to guarantee in many cases. For this reason we have used neural networks in conjunction with these methods to overcome this problem for the control of the reactor in this study. The neural network is used as a function estimator in the GMC method and as a model and controller in the IMC-PI method. Various simulations involving set point tracking and disturbance rejection under nominal and model-mismatch cases were performed using these hybrid methods. The results of these hybrid controllers were found to be better than the conventional PID and GMC methods in most cases. These results justify the use of the neural networks in such hybrid strategies as well as show their versatility in incorporating into the nonlinear control methods to cater for model mismatches and difficult to control process systems.抄録全体を表示PDF形式でダウンロード (321K)
Safety, Environment and Energy
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Degradation of Kenaf Core by Steam Explosion and Saccharification for Useful Utilization of BiowasteYOSHITOSHI NAKAMURA, TATSURO SAWADA, AKIHIRO KOMATSU, HIROSHI SAWADA, ...2001 年 34 巻 4 号 p. 549-552
発行日: 2001年
公開日: 2002/04/26
ジャーナル 認証ありIn order to use effectively the core after utilizing the bark in a kenaf plant, the degradation characteristics and enzymatic saccharification of steam exploded core were studied experimentally. The effects of the steam explosion on the modification of kenaf core, i.e. shape and size, pH, amounts of organic acids produced, and amounts of extracted components, were examined under various conditions. The saccharification of exploded kenaf core at a steam pressure of 2.5 MPa and a steaming time of 3 min was about 0.6; this suggests that about 85% of the holocellulose (hemicellulose and cellulose) contained in the kenaf core was converted into reducing sugars.抄録全体を表示PDF形式でダウンロード (1171K)
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