Study of magnetic field assisted mechanochemical polishing process for inner surface of Si3N4 ceramic components: Finishing characteristics under wet finishing using distilled water

This study discusses the finishing characteristics of a magnetic field assisted mechanochemical polishing process using Cr₂O₃ abrasive mixed with magnetic particles in the case of wet finishing using distilled water, which was proposed for internal finishing of Si₃N₄ fine ceramic tubes. It was clarified that a highly accurate finishing can be achieved more efficiently in the case of wet finishing using distilled water compared with dry finishing. Moreover, those conditions necessary to achieve high efficiency finishing are discussed.     

Clinicopathological features of lymph node metastasis in early gastric cancer

From 1979 through 1992, 482 cases with solitary early gastric cancer were resected in the Department of Surgery of the National Kyushu Medical Center Hospital. Among the 482 cases, the incidence of lymph node metastasis was 10.0% (48/482). The features of lymph node metastasis were studied while taking into account the combination of clinicopathological findings of the gastric cancer. Lymph node metastasis was rare in both the differentiated type mucosal cancers and submucosal cancers measuring 20 mm or smaller in size without depression. From these results, for early gastric cancer with the above-mentioned characteristics, either endoscopic therapy or local resection without lymph node dissection is considered to be sufficient treatment to obtain a favorable outcome.     

Novel system of electro-catalysts for methanol oxidation based on platinum and organic metal complexes

Novel system of electro-catalysts was developed for methanol oxidation reaction (MOR) in direct methanol fuel cells. Mixture of platinum tetraammine complex with cobalt quinolyldiamine complex with various mixing ratio was supported on graphite powder, and heat treated at 400-1000 °C in argon atmosphere. Powder thus obtained was put on a graphite disk electrode, and tested for electrochemical MOR in acid media. Although the cobalt complex itself showed almost no catalytic ability for MOR, it enhanced the activity of Pt more than several 10-fold when it was mixed with Pt. MOR performance was best exploited at about equal mixing ratio of platinum and cobalt complexes. Compared with platinum-ruthenium alloy catalysts, the new catalysts exhibited promising catalytic ability. The present investigation revealed good potentiality of organic complex catalysts in combination with metal catalysts for MOR, which opens the way to synthesize and develop a new class of electro-catalysts of low cost through wide range of molecular designing.     

Synthesis of chemically modified chitosans with a higher fatty acid glycidyl and their adsorption abilities for anionic and cationic dyes

Novel chitosan‐based materials with a higher fatty acid glycidyl as the chemically modified agent were synthesized and the adsorption ability of the resulting polymers has been evaluated for typical anionic and cationic dyes. The successful modification was confirmed by the infrared spectroscopic measurements. As the degree of substitution was decreased, the adsorption ability of the chemically modified chitosans for anionic dyes at the higher dye concentration was increased, and the modified chitosans with a lower degree of substitution showed a higher adsorption ability than that of an activated carbon at the higher dye concentration. For cationic dyes, the chemically modified chitosan showed a good adsorption power, especially when the adsorption power was evaluated by the flow methods. The improved adsorption ability of a chemically modified chitosan material was also confirmed by comparing it with that of a crosslinked chitosan material. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 96: 2423–2428, 2005     

Terpendole E and its Derivative Inhibit STLC‐ and GSK‐1‐Resistant Eg5

Terpendole E is first natural product found to inhibit mitotic kinesin Eg5, but its inhibitory mechanism remains to be revealed. Here, we report the effects of terpendole E and 11ketopaspaline (a new natural terpendole E analogue) on the Eg5–microtubule interaction and in several Eg5 mutants. 11‐Ketopaspaline is a shunt product from terpendole E, and it shows potent inhibitory activity against the microtubule‐stimulated ATPase activity of Eg5. Unlike other Eg5 inhibitors, such as S‐trityl‐L ‐cysteine (STLC) and GSK‐1, both terpendole E and 11‐ketopaspaline only partially inhibited Eg5–microtubule interaction. Furthermore, terpendole E and 11‐ketopaspaline inhibited several Eg5 mutants that are resistant to STLC (Eg5^D130A, Eg5^L214A) or GSK‐1 (Eg5^I299F, Eg5^A356T), but with the same extent of inhibition against wild‐type Eg5. Because Eg5^D130A and Eg5^L214A show cross‐resistance to most known Eg5 inhibitors, which bind the L5 loop, these results suggest that terpendole E and its analogues have a different binding site and/or inhibitory mechanism to those for L5 loop‐binding type Eg5 inhibitors.     

The geodesic dynamic relaxation method for problems of equilibrium with equality constraint conditions

This paper presents an extension to the existing dynamic relaxation method to include equality constraint conditions in the process. The existing dynamic relaxation method is presented as a general, gradient‐based, minimization technique. This representation allows for the introduction of the projected gradient, discrete parallel transportation and pull back operators that enable the formulation of the geodesic dynamic relaxation method, a method that accounts for equality constraint conditions. The characteristics of both the existing and geodesic dynamic relaxation methods are discussed in terms of the system's conservation of energy, damping (viscous, kinetic, and drift), and geometry generation. Particular attention is drawn to the introduction of a novel damping approach named drift damping. This technique is essentially a combination of viscous and kinetic damping. It allows for a smooth and fast convergence rate in both the existing and geodesic dynamic relaxation processes. The case study was performed on the form‐finding of an iconic, ridge‐and‐valley, pre‐stressed membrane system, which is supported by masts. The study shows the potential of the proposed method to account for specified (total) length requirements. The geodesic dynamic relaxation technique is widely applicable to the form‐finding of force‐modeled systems (including mechanically and pressurized pre‐stressed membranes) where equality constraint control is desired. Copyright © 2014 John Wiley & Sons, Ltd.     

3D Micromolding of Arrayed Waveguide Gratings on Upconversion Luminescent Layers for Flexible Transparent Displays without Mirrors,Electrodes, and Electric Circuits

A new technique for the fabrication of arrayed waveguide gratings on upconversion luminescent layers for flexible transparent displays is reported. Ho³⁺‐ and Yb³⁺‐codoped NaYF₄ nanoparticles are synthesized by hydrothermal techniques. Transparent films consisting of two transparent polymers on the NaYF₄ nanoparticle films exhibit mechanical flexibility and high transparence in visible region. Patterned NaYF₄ nanoparticle films are fabricated by calcination‐free micromolding in capillaries. Arrayed waveguide gratings consisting of the two transparent polymers are formed on the patterned NaYF₄ nanoparticle films by micromolding in capillaries. Green and red luminescence is observed from the upconversion luminescent layers of the NaYF₄ nanoparticle films in the arrayed waveguide gratings under excitation at 980 nm laser light. Arrayed waveguide gratings on the upconversion luminescent layers are fabricated with Er³⁺‐doped NaYF₄ nanoparticles which can convert two photons at 850 and 1500 nm into single photon at 550 nm. These results demonstrate that flexible transparent displays can be fabricated by constructing arrayed waveguide gratings on upconversion luminescent layers, which can operate in nonprojection mode without mirrors, transparent electrodes, and electric circuits.     

Photo atomic layer deposition of transparent conductive ZnO films

Low-resistivity ZnO films were grown by photo atomic layer deposition (photo-ALD) technique using diethylzinc (DEZ) and H₂O as reactant gases. Self-limiting growth was achieved for the temperature range from 105°C to 235°C. It was found that UV light irradiation was very effective to increase the electron concentration of the films and the electron concentration of 5 × 10²⁰ cm⁻³ was achieved even in undoped ZnO. Thus, the resistivity of the films grown with UV irradiation was one order of magnitude less than that grown without UV irradiation. The minimum resistivity of 6.9 × 10⁻⁴Ω cm was obtained by photo- ALD method without any intentional doping.