Germanium recovery using polyphenol microspheres prepared by horseradish peroxidase reaction

BACKGROUND: The formation of polyphenol microspheres by the polymerization of 3‐methylcatechol was performed in a methanol/phosphate buffer solution using horseradish peroxidase (HRP), without the use of a surfactant or a water/oil interface, to be used for germanium recovery. RESULTS: The polyphenol microspheres were of diameter 1 mm. The functional group density of phenol group in the polymer was approximately 15 mol kg^?1 determined by the Folin‐Denis method. In batchwise experiments, the amount of germanium adsorbed was 0.23 mol kg^?1. CONCLUSION: Because germanium is a rare metal, a system for its recovery is required. Using the proposed system, continuous recovery of germanium can be achieved using multilayered microspheres. Copyright © 2011 Society of Chemical Industry     

Preparation of micrometer‐sized,multifunctional capsule particles for cosmetic by microsuspension polymerization utilizing the self‐assembling of phase separated polymer method

Micrometer‐sized polymer particles with encapsulated ultraviolet (UV) absorbent, fluorescent agent, and blue pigment were successfully prepared by microsuspension polymerization utilizing the Self‐assembling of Phase Separated Polymer method. The particles were characterized by optical microscope and particle size distribution analysis, and they were evaluated on their usefulness for cosmetic using UV spectrometry, colorimetry, VISIA? Evolution, and bioassay. The capsule particles had multifunctional properties, which are very attractive in the cosmetic field, especially in whitening, brightening, the improvement of face‐texture, and less noticeable pores in face, as well as the protection from UV. Moreover, bioactivities of the particles under the UV irradiation, which were examined with the films prepared from capsule components, revealed not only makeup effect but also the activation of human epidermal keratinocytes. The results suggest the importance of blue light in the field of cosmetics. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

SOLUBILITY IN ORGANIC DILUENTS AND EXTRACTION BEHAVIOR OF CALIX[4]ARENE CARBOXYLATES WITH DIFFERENT ALKYL CHAINS

ABSTRACT

Two types of alkylcalix[4]arene carboxylates with different alkyl chains, together with three types with the same alkyl chains were synthesized to investigate their solubility in four different organic diluents. The solubility was found to be enhanced by using the calixarene compounds with longer alkyl chains and by using mixtures of compounds with different alkyl chains. The order of solubility in the different organic diluents was found to be:

chloroform > toluene ? EXXSOL D80 ≈ hexane.

The stoichiometry of the copper complex with the compounds having the same alkyl chains was also determined and the maximum loading capacity of copper with each extractant was estimated.     

Studies on chitin. IX. Crosslinking of water-soluble chitin and evaluation of the products as adsorbents for cupric ion

Water-soluble chitin was successfully crosslinked to varying extents with glutaraldehyde in homogeneous aqueous solutions to improve the properties as an adsorbent for metal cations, and the effects of crosslinking were discussed. Complete insolubilization was achieved with the fivefold excess aldehyde, but, in terms of adsorptivity of Cu²⁺, the chitin crosslinked at an aldehyde/amino group ratio of 1.0 was found to exhibit remarkable capacity and was much superior to others. The desorption of Cu²⁺ from the adsorption complex was also attained effectively at pH 2.0. These results indicated that the loose crosslinking was quite simple and efficient to produce high capacity adsorbents for practical use. Thermal behavior of the crosslinked chitin was examined by TMA and TGA; a softening phenomenon was observed at 145°C.     

Recent situation of industrial implementation of Cat-CVD technology in Japan

Efforts of industrial application of Cat-CVD technology are surveyed. Recent movement of industrial implementation is also reviewed by showing examples in Japanese industry. Cat-CVD technology is originally developed as a new tool for fabricating semiconductor devices, however, recently, use of the technology is attempted in various fields such as chemical, mechanical and bio-technical engineering. It is shown that Cat-CVD has high feasibility as a fundamental technology of modern industries.     

Liquid-liquid extraction for efficient synthesis and separation by utilizing micro spaces

Enhancement of mass transfer between two phases and improvement of extraction efficiency are expected if features of micro spaces are adopted for a liquid-liquid two-phase process. In this work, three extraction operations, contact flow in a Y-shaped microchannel, segmented flow and emulsification, have been investigated. Extraction using segmented flow is dependent on mass transfer by molecular diffusion and its rate is enhanced by the internal circulation flow generated inside slugs. The extraction rate can be controlled precisely by adjusting operational parameters such as the flow rate and the flow rate ratio. Liquid-liquid two-phase separation can be achieved instantly. Thus, continuous operation of a process involving liquid-liquid extraction and then two-phase separation is expected to be possible. For extraction based on emulsification, rapid extraction is made possible owing to significant increase in the interfacial area. Though extraction itself is rapid, liquid-liquid separation may take a long time because coalescence of stable emulsions requires time. It is suitable for systems strongly requiring only rapid extraction. Advanced reaction-separation systems can be developed by combining the extraction operations, making full use of the characteristics of segmented flow or emulsification and the reaction.     

Dynamic breakdown characteristics of liquid helium induced by aquench of superconducting wire and coil

For practical insulation design of superconducting power apparatus, it is necessary to take into account an inherent phenomenon known as quench, the transition from the superconducting to the normal state. We investigated quench-induced dynamic breakdown and prebreakdown characteristics of liquid helium (LHe). Experimental results revealed that the quench of the superconductor drastically reduced the breakdown voltage of LHe in the thermal bubble disturbance. Moreover, dynamic breakdown characteristics in a quasi-uniform field using a superconducting coil were investigated. The results revealed that the breakdown was induced in the quench-initiated region where the largest thermal energy was generated