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Predecessor
Volume 83, Issue 2
Displaying 1-6 of 6 articles from this issue
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Original Research Paper
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Yo SASAKI, Syuhei HAYASHI, Zentaro TOKUYASU, Yoichi ONO, Mitsunobu IWA ...2010 Volume 83 Issue 2 Pages 53-58
Published: February 15, 2010
Released on J-STAGE: May 20, 2010
JOURNAL FREE ACCESSTantalum nitrides and oxynitrides, such as Ta3N5 and TaON, respectively, have exhibited promising properties as red and yellow pigments that do not contain toxic heavy metals. We have developed a process for preparing nitrides or oxynitrides that involves the vacuum-calcination of a precursor material obtained by reaction between a metal halide and liquid NH3. Herein, we describe the synthetic conditions of the liquid NH3 process that affects the color, and thus the color characteristics of resulting pigments. Reaction and post-reaction treatment conditions were adjusted to attain the desired red color ; specifically, a powder with a color index of L*=a*=33.11 and b*=30.53 was obtained by the liquid NH3 process using 0.5 eq of NH2OH-HCl (relative to TaCl5) as the oxygen source, and calcination of the precursor at 973 K under vacuum, followed by recalcination at 673 K for 60 min under air.View full abstractDownload PDF (781K)
Original Technical Paper
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Minoru TSUBOTA, Kazunari UEDA, Hiroshi FUKUI2010 Volume 83 Issue 2 Pages 59-65
Published: February 15, 2010
Released on J-STAGE: May 20, 2010
JOURNAL FREE ACCESSIn this paper, we investigated the effect of surface modification of magnetic particles on their dispersibility and the physical properties of their paints. By CVD process, a thin layer of cross-linked polymethylsiloxane (PMS) was formed on a whole particle. This PMS layer played roles of a barrier of magnetic attractions and increasing a wettability to the binders used. The PMS layer contributed to the improvement of the dispersibility and the compatibility to the binders, and the breaking elongation of the films filled with the particles having PMS increased more than 4 times of those with untreated particles. The CVD process was effective in the coating fields.View full abstractDownload PDF (2556K)
Review
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Masanobu SAGISAKA, Atsushi YOSHIZAWA2010 Volume 83 Issue 2 Pages 66-75
Published: February 15, 2010
Released on J-STAGE: May 20, 2010
JOURNAL FREE ACCESSAs an alternative to toxic organic solvents, supercritical carbon dioxide (scCO2) has attracted much attention over the last decade since it is nontoxic, inflammable, environmentally friendly, low cost and readily available in large quantities. With these advantages, together with its unique properties as a supercritical fluid such as adjustable solvent power, enhanced mass transfer characteristics and low surface tension, scCO2 has prompted extensive research to develop scCO2-based processes. Unfortunately, because CO2 is nonpolar and has weak van der Waals forces, it is not suitable for dissolving polar substances ; this fact has limited its application to processes such as separation, reaction, and material formation. One approach to overcoming this limitation is to employ specialized scCO2 soluble surfactants that induce formation of reversed micelles with high-density aqueous cores in the continuous scCO2 phase, that is, water-in-scCO2 (W/scCO2) microemulsions. Since such systems would combine the attractive characteristics of scCO2 with the solvating properties of bulk water, it is expected to be a ‘universal solvent’. This paper introduces how to design suitable surfactant structures capable of forming stable W/scCO2 microemulsions containing a large amount of water, properties of W/scCO2 microemulsions, and their industrial application.View full abstractDownload PDF (2993K) -
Tomohiro IMURA, Tokuma FUKUOKA, Tomotake MORITA, Masaru KITAGAWA, Dai ...2010 Volume 83 Issue 2 Pages 76-81
Published: February 15, 2010
Released on J-STAGE: May 20, 2010
JOURNAL FREE ACCESSBiosurfactants (BS) are functional amphiphilic compounds produced from renewable sources by a variety of microorganisms. They show unique properties (e.g. mild production conditions, multifunctionality, higher biocompatibility and environmental compatibility) compared to chemically synthesized counterparts. BS have thus been receiving increasing attention as surfactants contributing to low-carbon society. Mannosylerythritol lipids (MELs) are one of the most promising glycolipid BS known, and are abundantly produced (>100 g/L) from vegetable oils by the yeast strains belonging to the genus Pseudozyma. MELs exhibit excellent interfacial and self-assembling properties leading to the formation of different lyotropic liquid crystals such as sponge (L3), bicontinuous cubic (V2), and lamellar (Lα) phases. They also show versatile biological properties including antitumor and cell differentiation-inducing activities. More significantly, they also show ceramide-like moisturizing actions to human skin. The yeast glycolipid BS thus be novel nanobiomaterials, and broaden their applications in various advanced technologies.View full abstractDownload PDF (2697K)
Current Topics
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Koji TSUCHIYA2010 Volume 83 Issue 2 Pages 82-88
Published: February 15, 2010
Released on J-STAGE: May 20, 2010
JOURNAL FREE ACCESSWe report the preparation and ultrasound imaging of micro/nano bubbles with an antibody (anti-CD147) for ultrasound contrast agents. Newly synthesized cycloamylose-modified surfactant (CL) and polymerizable anionic gemini surfactant (Poly-G-SDMT) were used for the preparation of “nanobubbles”. Sulfur hexafluoride (SF6) and 30% glycerin aqueous solution were respectively used as entrapped gas and solvent for the stabilization of bubbles. Nanobubbles with the size of about 200 nm were prepared by the irradiation of ultrasonic wave (20 kHz) and clearly imaged by ultrasound.
Then, an antibody (anti-CD147) which selectively adsorbs on tumor tissues was labeled to phospholipid microbubbles. Ultrasound imaging for the microbubbles labeled with anti-CD147 was tried using a Radial Flow Bioreactor (RFB). To create a three-dimensional model of liver organoid, a hydroxy apatite-fiber scaffold (AFS) column was used, and a human liver tumor (FLC-7) was attached to the column. Interestingly, ultrasound images of the anti-CD147-labeled microbubbles revealed the selective accumulation of the labeled microbubbles to the liver tumors. In contrast, microbubbles prepared by a commercial ultrasound contrast agent showed a poor accumulation activity on the liver tumors. Thus, anti-CD147-labeled microbubbles obtained in this study would be a promising ultrasound agent which allows to target tumor tissues.View full abstractDownload PDF (1876K) -
Hideki SAKAI2010 Volume 83 Issue 2 Pages 89-94
Published: February 15, 2010
Released on J-STAGE: May 20, 2010
JOURNAL FREE ACCESSPore- and crystalline structure control of mesoporous titania prepared with surfactant molecular assemblies as structure directing agents is studied shedding light on the effect of molecular structure and aggregation state of the surfactant. Mesoporous titania bearing crystalline wall was successfully prepared by using molecular assemblies formed by a quarternary ammonium type cationic surfactant as a “self-organized catalyst”. Pore size enlargement was made possible by using hexagonal liquid crystal solubilizing aromatic oily substances like triethylbenzene and trimethylbenzene as “self-organized catalyst”.View full abstractDownload PDF (2389K)
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