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Volume 40, Issue 1
Displaying 1-13 of 13 articles from this issue
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Physical Properties and Physical Chemistry
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Kensuke Yoshida, Hiroshi Yamamoto, Katsumi TochigiArticle type: Short Communication
2007 Volume 40 Issue 1 Pages 1-4
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSAs new alternatives to CFCs and HCFCs, HFEs have been proposed for cleaning solvents by the Research Institute of Innovative Technology for the Earth (RITE). Azeotropic mixtures composed of HFEs and solvents are essential to improve the low solubility of HFEs. For developing the predictive method of such phase equilibria, the ASOG parameters have been already reported for the systems containing HFEs, alcohols, ketones, esters and ethers.
This paper deals with revision of ASOG group pair parameters relating to CF2, CHF2, and CHF groups using binary VLE data. The correlated accuracies of vapor composition and bubble points are 0.016 mole fraction and 0.98 K, respectively, for 45 binary systems.View full abstractDownload PDF (416K)
Transport Phenomena and Fluid Engineering
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Shuichi ToriiArticle type: Research Paper
2007 Volume 40 Issue 1 Pages 5-11
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSThe aim of the present study is to investigate convection heat transfer and fluid flow in an insulated rectangular cavity, i.e., an indoor with the injection and suction ducts. Emphasis is placed on the effect of a vertical partition plate in the cavity on the thermal and velocity fields and local area heating-performance. The numerical method is based on the incompressible Navier–Stokes and energy equations. The fluid in the cavity in the absence of the vertical partition plate shows the large clockwise flow pattern and as time progresses, the fluid temperature is gradually increased and becomes uniformly over the whole region of the cavity. When the vertical plate is installed at the central location of the upper horizontal wall, the higher velocity field appears in the left area of the indoor and the corresponding fluid temperature is higher than that of the right area. By installing the partition plate, the temperature distribution in the indoor is controlled. In other words, only the desired space of the cavity is warmed, because the flow pattern is changed due to the presence of the plate. The optimum partition plate height is obtained based on the numerical and experimental results.View full abstractDownload PDF (3862K) -
Mio Isaji, Shinichi Ookawara, Kohei OgawaArticle type: Short Communication
2007 Volume 40 Issue 1 Pages 12-16
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSInstantaneous successive particle collision within tens of milliseconds is visualized by the collision sound detection method. The main mechanism seems to be the discharge of a particle due to the collision against the circulation flow in the tank and the re-entrainment of the particle into the circulation flow leading to the immediate next collision. It is confirmed that the rate of instantaneous successive collisions to total successive collisions is about 22% in the examined conditions. Further, the rate is found to be practically constant in sufficiently solid-suspended conditions.View full abstractDownload PDF (1838K)
Separation Engineering
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Hossein Bahmanyar, Farideh Ghasempour, Jaber SafdariArticle type: Research Paper
2007 Volume 40 Issue 1 Pages 17-25
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSLiquid–liquid extraction is one of the best techniques in separation and a mixer settler is one of these separation contactors. In this research, Hanson’s vertical mixer settler has been designed and built. The effects of the agitation rate, dispersed and continuous phases volumetric rates and interfacial tension on the dispersed phase hold-up in with and without mass transfer conditions have been studied. The results show that, by increasing the agitation rate and dispersed phase volumetric rate, the hold-up increases and the interfacial tension and continuous phase volumetric rate have reverse effects. The behaviors of hold-up with variations of operating parameters in conditions with and without mass transfer are similar but the values of mass transfer conditions are lower. Generally the proportionality between the hold-up and operating parameters in two above-mentioned conditions are found.View full abstractDownload PDF (1057K) -
Michiaki Matsumoto, Takashi Sugimoto, Kouji Kusumoto, Kazuo KondoArticle type: Research Paper
2007 Volume 40 Issue 1 Pages 26-30
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSDiols are key intermediate materials for polymers. Conventional distillation techniques for the separation of diols require a substantial energy input. Alternatively, in this paper we examine an adsorption technique to recover and separate diols. Silica gels modified by boronate were used as a selective adsorbent for diols. First, using potentiometric titration, we examined the number and pKa of the active site included in the gels. The values of the pKa of the boronate were larger than that of phenylboronic acid. From the adsorption experiments on the resin, we found that main adsorption mechanism was a complex formation between neutral boronic acid and the diols. A pH value smaller than pKa (=10) of boronate is desirable for the adsorption of diols. Silica gels modified by phenylboronic acid effectively adsorbed the hydrophobic diols. The adsorption capacity of vicinal and 1,3-diols were similar.View full abstractDownload PDF (439K) -
Kazuo Kondo, Morio Ishihara, Michiaki Matsumoto, Eiji KamioArticle type: Short Communication
2007 Volume 40 Issue 1 Pages 31-35
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSThe fundamental investigation on extraction of Pd(II), Pt(IV), Cr(VI), Cu(II), Ni(II) and Zn(II) from an aqueous solution by using microcapsules containing a metal extractant was investigated. As extractants, 2-ethylhexylphosphonic acid mono-2-ethylhexyl ester (EHPNA) and tri-n-octylamine loaded with hydrochloric acid (TOA-HCl) were used. The extractants were successfully encapsulated in the microcapsules during the in situ microencapsulation process. The extractability of the metals into the microcapsules was estimated from the extraction isotherm of the metals. According to the Langmuir model, the saturation amount of metal extracted and the extraction equilibrium constant were determined. The microcapsules containing EHPNA and TOA-HCl were suitable for the extraction of base metals and precious metals, respectively. It is anticipated that a reactor in which two columns packed with each microcapsule containing EHPNA and TOA-HCl are connected in series would be useful for separation and recovery of precious metals from base metals.View full abstractDownload PDF (549K)
Thermal Engineering
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Kenji Saita, Fumisato Goto, Masaya Ishida, Hiroshi HamamatsuArticle type: Research Paper
2007 Volume 40 Issue 1 Pages 36-43
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSThe present paper reports a study on the relation between the deactivation temperatures of five nucleating agents for supercooled NaCH3COO·3H2O and crystallographic matching on a point of view of the arrangement of Na atoms. The deactivation temperatures of Na2SO4, NaCl, NaBr, Na2HPO4·2H2O, and Na3PO4·0.5H2O were 333, 335, 339, 348, and 360 K, respectively. The crystal structural correlation between NaCH3COO·3H2O and five nucleating agents was studied from the point of view of the arrangement of Na atoms in a crystal face slice. Periodic matching of a pair of Na atoms was observed in the area of 200–400 square Å. The degrees of matching, defined as a reciprocal of the number of unit cells which were contained in a parallelogram with four matching points, of above five nucleating agents were 1.0, 1.9, 5.0, 20, and 25%, respectively. A positive correlation between the deactivation temperatures and the crystallographic matching was found.View full abstractDownload PDF (1685K)
Chemical Reaction Engineering
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Takehiro OhbaArticle type: Research Paper
2007 Volume 40 Issue 1 Pages 44-50
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSA pollutants-confining reaction system is proposed to prevent the environmental pollution problems caused by the waste materials from chemical reactors. In this reaction system, the formed by-products and the unreacted raw components are confined in the reactor, and only the product components can be collected. The by-products which are formed by parallel reactions can be preserved at some constant concentrations. Other by-products which are formed together with the product components are converted into the raw components by adding proper reactions. The product components are collected by using separation mechanisms such as membrane filters. This reaction system can be called an ideal reactor because all of the raw components are converted into the product components without environmental pollution. In this paper, a steady-state analysis is performed and the practical conditions are derived.View full abstractDownload PDF (769K)
Biochemical, Food and Medical Engineering
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Kosuke Ino, Akira Ito, Hirohito Kumazawa, Hideaki Kagami, Minoru Ueda, ...Article type: Research Paper
2007 Volume 40 Issue 1 Pages 51-58
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL FREE ACCESSOne of the major challenges in tissue engineering remains the construction of vascularized 3D transplants in vitro. We recently proposed novel technologies, termed “magnetic force-based tissue engineering” (Mag-TE), to establish three-dimensional (3D) tissues without using scaffolds. Magnetite cationic liposomes (MCLs), which contain 10-nm magnetite nanoparticles in order to improve accumulation of magnetite nanoparticles in target cells, were used to magnetically label normal human dermal fibroblasts (NHDFs). Magnetically labeled NHDFs were seeded onto ultralow-attachment plates. When a magnet was placed under the plate, cells accumulate on the bottom of the well. After a 24-h-incubation period, the cells form a sheet-like structure, which contains the major dermal extracellular matrix (ECM) components (fibronectin and type I collagen) within the NHDF sheet. Human umbilical vein endothelial cells (HUVECs) were co-cultured with NHDF sheets by two methods: HUVECs and NHDFs were mixed and then allowed to form cell sheets by Mag-TE; or NHDF sheets were constructed by Mag-TE and HUVECs were subsequently seeded onto NHDF sheets. These methods gave tube-like formation of HAECs, resembling early capillaries, within or on the surface NHDF sheets after short-term 3D co-culture, thus suggesting that Mag-TE may be useful for constructing 3D-tissue involving capillaries.View full abstractDownload PDF (6185K) -
Md. Fida Hasan, Yuka Kobayashi, Yoichi Kumada, Tomohisa Katsuda, Masaa ...Article type: Short Communication
2007 Volume 40 Issue 1 Pages 59-62
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSInhibition characteristics of tri-peptides IKW and IKY, which were obtained as angiotensin-I converting enzyme inhibitors from bonito protein, and their stability in digestive canal were studied. These IKW and IKY showed high inhibitory activities with IC50 of 0.4 and 1.0 μM, respectively, and acted as competitive inhibitors. The tri-peptides, especially IKY, were very stable under simulated gastrointestinal digestion conditions.View full abstractDownload PDF (358K)
Materials Engineering and Interfacial Phenomena
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Keigo Hanaki, Nobuaki Nonoyama, Yasuaki Yabuki, Yoshiaki Kato, Izumi H ...Article type: Research Paper
2007 Volume 40 Issue 1 Pages 63-71
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSThis paper describes a simple method for designing a batch cooling crystallization of a pharmaceutical under constant supersaturation. The simple model assumes that crystal growth is the predominant mechanism during the crystallization and requires only two parameters, crystal growth rate constant and solubility. Both parameters are functions of temperature and are obtained simultaneously by conducting a single experiment with multiple-step cooling. The model was validated through additional natural cooling and controlled cooling crystallization experiments. Finally, it was demonstrated experimentally that the supersaturation throughout the crystallization process was effectively kept constant by applying the cooling trajectory predicted by the model.View full abstractDownload PDF (1315K)
Energy
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Toshio Ichihashi, Yoshio Nakano, Mitsuteru Ogawa, Hitoshi Higo, Tatsuy ...Article type: Research Paper
2007 Volume 40 Issue 1 Pages 72-79
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSWe have proposed a new open-cycle desiccant air-conditioning system using a thermo-sensitive water vapor adsorbent that has a phase transition temperature below 333 K, which is expected to result in energy saving. In this system, it is necessary to suppress the rise in the temperature of the adsorbent to be below the phase transition temperature during adsorption. In this study, the performance of a plate heat exchanger type adsorption reactor that has a function of cooling the adsorbent bed was evaluated using a simulation model as well as some other experiments. This model simulated well the characteristics of water vapor transfer and heat transfer in the adsorbent bed. In addition, the simulation results showed that heightening the effective thermal conductivity of the adsorbent bed was more effective than decreasing the coolant temperature in order to obtain the improved effect of the stable cooling capability of the adsorbent bed over time. This simulation method is very useful for the configuration design of a plate heat exchanger type adsorbent reactor.View full abstractDownload PDF (581K) -
Mitsuhiro Kubota, Erwin P. Ona, Fujio Watanabe, Hitoki Matsuda, Hideto ...Article type: Short Communication
2007 Volume 40 Issue 1 Pages 80-84
Published: 2007
Released on J-STAGE: January 19, 2007
JOURNAL RESTRICTED ACCESSThis study investigated a novel idea of combining an organic component erythritol with an inorganic component MgCl2·6H2O to prepare new PCMs suitable for domestic water heating. A DSC analysis indicated that mixtures containing less than 20 wt% MgCl2·6H2O have melting temperatures above 353 K and latent heat values greater than 120 kJ/kg. Thermal cycling of erythritol-based PCMs in test tubes showed good stability in terms of nucleation temperature. However, the erythritol-based PCMs were found to undergo supercooling of about 50 K below the melting temperature, similar to erythritol. An analysis of the distribution of the salt hydrate component in the solid phase in a scale-up experiment revealed the salt hydrate’s possibility of accumulating at the bottom of the unit. The effect of ultrasonic irradiation on prevention of component segregation was also demonstrated.View full abstractDownload PDF (447K)
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