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51.
Characterization of the chemical conversion films that form on Mg−Al alloy in colloidal silica solution 总被引:1,自引:0,他引:1
Seong?-Jong?KimEmail author Ying?Zhou Ryoichi?Ichino Masazumi?Okido Shoji?Tanikawa 《Metals and Materials International》2003,9(2):207-213
Chemical conversion treatment of Mg−Al alloy (AZ91) using colloidal silica as an alternative to chromate conversion was investigated
as a function of solution pH, temperature, solution conditions, and treatment time. The solution used for the colloidal silica
coating consisted of colloidal silica, titanium sulfate, and cobalt ions to maintain good anti-corrosion and adhesion properties.
Adding CoSO4 to the colloidal silica solution enhanced the adhesion force between the silica film and magnesium substrate. The optimum
conditions for the chemical conversion treatment solution were pH 2, 90-sec treatment, and 25°C. 相似文献
52.
Satoh M Sakaguchi M Kobata M Sakaguchi Y Tanizawa H Miura Y Sasano R Nakanishi Y 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2003,44(1):7-12
We studied the effect of cleaning and cooking on the residues of flutolanil, fenobucarb, silafluofen and buprofezin in rice. The rice had been sprayed in a paddy field in Wakayama city, with 3 kinds of pesticide application protocols: spraying once at the usual concentration of pesticides, repeated spraying (3 times) with the usual concentration of pesticides and spraying once with 3 times the usual concentration of pesticides. The residue levels of pesticide decreased during the rice cleaning process. Silafluofen, which has a higher log Pow value, remained in the hull of the rice. Fenobucarb, which has a lower log Pow value, penetrated inside the rice. The residue concentration of pesticide in polished rice was higher than that in pre-washed rice processed ready for cooking. During the cooking procedure, the reduction of pesticides in polished rice was higher than that in brown rice. 相似文献
53.
Horiuchi S Hamanaka T Aoki T Miyakawa T Narita R Wakabayashi H 《Journal of electron microscopy》2003,52(3):255-266
Energy-filtering transmission electron microscopy (EFTEM) was applied for investigating interfaces between a polymer and an adhesive. The sample employed in this work is polybutylene terephtharate (PBT) sheets laminated with an epoxy adhesive. It was found that heat aging of the PBT at 180 degrees C in air for > 9 h prior to adhesion decreases the adhesion strength drastically. To investigate this unfavourable aging effect on the adhesion strength, we performed elemental mapping and image EELS using EFTEM. A weak boundary layer with a thickness of < 50 nm was visualized at the PBT-adhesive interface by elemental mapping in the sample subjected to the heat aging and image EELS revealed the origin of this layer. Thus, we clearly correlated the nanoscale interfacial structure with the adhesion strength by EFTEM. 相似文献
54.
Production of L-erythrose via L-erythrulose from erythritol using microbial and enzymatic reactions 总被引:4,自引:0,他引:4
Mizanur RM Takeshita K Moshino H Takada G Izumori K 《Journal of Bioscience and Bioengineering》2001,92(3):237-241
A rare aldotetrose, L-erythrose, was produced from erythritol via a two-step reaction. In the first step, complete oxidation of erythritol to L-erythrulose was achieved by using Gluconobacter frateurii IFO 3254. Washed cell suspension of the strain grown on tryptic soy broth (TSB) supplemented with 1% d-sorbitol was used to carry out the transformation reaction at 30 degrees C with shaking at 170 rpm. At 10% substrate concentration, 98% erythritol was converted to L-erythrulose within 48 h. The produced L-erythrulose was then used as a substrate for the production of L-erythrose. The isomerization of L-erythrulose to L-erythrose was carried out using constitutively produced L-ribose isomerase (l-RI) from the mutant strain Acinetobacter sp. DL-28 grown on D-lyxose mineral salt medium. At equilibrium, the yield of L-erythrose from L-erythrulose was 18% and finally 1.7 g L-erythrose was obtained from 10 g erythritol. After a number of simple purification steps, the product was isolated from the reaction mixture by ion-exchange column chromatography (Dowex 50W-X2, Ca2+). The structure of the product was determined after NaBH4 reduction from Infrared (IR) and 13C nuclear magnetic resonance (NMR) spectra. 相似文献
55.
Yosuke Kimura Masaharu Asano Ryoichi Katakai 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2007,263(2):463-467
Poly(ethylene-co-tetrafluoroethylene) (ETFE) films were irradiated by swift heavy ion-beams of 129Xe23+ with fluences of 0, 3 × 106, 3 × 107, 3 × 108 and 3 × 109 ions/cm2, followed by γ-ray pre-irradiation for radiation grafting of styrene onto the ETFE films and sulfonation of the grafted ETFE films to prepare highly anisotropic proton-conducting membranes. The fluence of Xe ions and the addition of water in the grafting solvent were examined to determine their effect on the proton conductivity of the resultant membranes. It was found that the polymer electrolyte membrane prepared by grafting the styrene monomer in a mixture of 67% isopropanol and 33% water to the ETFE film with an ion-beam irradiation fluence of 3.0 × 106 ions/cm2 was a highly anisotropic proton-conducting material, as the proton conductivity was three or more times higher in the thickness direction than in the surface direction of the membrane. 相似文献
56.
Jun‐Hak Lee Takahiko Horiuchi Ryoichi Saito 《Journal of the Society for Information Display》2007,15(7):507-518
Abstract— The reduction of a structural pattern at specific gray levels caused by digital halftone methods is the subject of this paper. This problem is more severe in some flat‐panel displays because their black levels typically are brighter than other display blocks. A patented halftone algorithm, confined error diffusion (CED), that confines the error‐carry within the dither mask is described and extended. First, the CED algorithm that dynamically applies random error diffusion or the ordered‐dither method, depending upon image content, is described in detail. Finally, we propose an advanced CED algorithm for improving the gradation characteristics of the CED algorithm. The performance of the proposed algorithms is compared to the experimental results for natural test images. In order to verify the halftone quality, a structural similarity measure for color images by taking into account the interrelation between color channels is proposed, and the results based on the proposed method, the color similarity measure method, is given. 相似文献
57.
J. Chen H. T. Takeshita D. Chartouni N. Kuriyama T. Sakai 《Journal of Materials Science》2001,36(24):5829-5834
The stoichiometric mixture of 2MgH2 + Co was ball milled under a hydrogen atmosphere to synthesize nanocrystalline metal hydride Mg2CoH5. Upon milling, the mixture was analyzed by X-ray powder diffraction (XRD) and thermal methods employing the techniques of differential scanning calorimetry (DSC), thermogravimetry (TG) and differential thermal analysis (DTA). Hydrogen absorption and desorption measured by pressure-composition-temperature (P-C-T) curves indicated that the capacity loss was small after 20 consecutive cycling tests. The enthalpies associated with hydride formation and decomposition were measured to be –69.5 and –83.2 kJ mol–1 H2, respectively. At the temperatures of this study (553 to 653 K), hysteresis decreases with increasing temperature. 相似文献
58.
Sugita Y. Suzuki R. Ikeda T. Takeuchi T. Kodama N. Takeshita M. Imura R. Satoh T. Umezaki H. Koyama N. 《IEEE transactions on magnetics》1986,22(4):239-246
Hybrid bubble memory devices have been proposed and operated with the memory density of 4 Mbit/cm2. In the hybrid bubble memory devices, minor loops are composed of ion-implanted tracks with 4-µm period, and major lines and functional parts including block-replicate and swap gates are composed of Permalloy tracks with a longer period of 12 µm. Passive junctions between ion-implanted and Permalloy tracks have been developed, introducing the tapered ion-implantation technique. Improving the characteristics of the functional parts composed of Permalloy tracks, the hybrid bubble memory devices with block-replicate and swap gates have been operated, and the feasibility of the devices has been confirmed. In addition, the possibility of higher memory density has been shown. 相似文献
59.
Kouichi Asakura Ayuko Iida Ryoichi Kitagata Atsushi Yoshida Shuichi Osanai Akihiro Kuroda 《Journal of surfactants and detergents》2001,4(4):375-378
Adsorption properties of two types of dimethylpolysiloxane backbone derivatives, perfluoroalkyl polyoxyethylenated dimethylpolysiloxane
(FPD) and polyoxyethylenated dimethylpolysiloxane (PD), onto keratin surfaces were investigated. Both polymers are amphiphilic,
since they possess hydrophilic polyoxyethylene groups. FPD contains a perfluoroalkyl group that provides both water-and oil-repellent
properties, whereas PD lacks these groups. Adsorption properties of these polymers onto keratin surfaces are considered a
good index to evaluate these compounds as nonionics used in hair-coating agents, since keratin is a major component of hair.
FPD was more likely to be adsorbed and less likely to be eliminated from the keratin surface than PD. Once FPD had been adsorbed
onto the keratin surface, it was very slowly washed from the surface when it was immersed in stationary water, whereas PD
polymers were quickly washed from the keratin surface. Even in running water, rapid elimination of FPD was not observed. The
strong resistance to loss of FPD after washing with a large quantity of water may be due to the water-repellent nature of
the perfluoroalkyl groups. As a comparison, FPD adsorption onto a glass surface was also investigated. The affinity to the
glass surface was found to be less than to the keratin surface. 相似文献
60.
Yukitoshi Takeshita Takuya Kamisho Seizo Sakata Takashi Sawada Yoshikazu Watanuki Ryuichi Nishio Toshinobu Ueda 《Journal of Coatings Technology and Research》2013,10(4):503-514
To improve alkaline resistance, a newly mixed powder coating film using thermoplastic polyethylene terephthalate (PET) was investigated. Two kinds of polyvinyl butyral (PVB) and two kinds of polyamide (PA) were chosen as the secondary polymer. The melting temperatures (T ms) of these materials were lower than that of primary PET polymer so the mixed powder coating was able to form a dual phase film through a fluidized bed coating process. Microscope and Fourier transform infrared spectroscopy (FTIR) observations revealed that the dual phase structure was indeed successfully formed and there was a secondary layer over the entire surface area of the film. This mixed powder coating film significantly enhanced the alkaline resistance to an environment filled with NaOH solution at 40°C in which a secondary material would be effective in protecting the film. With regard to both alkaline resistance and film formability, PET/PVB was superior to the PET/PA mixture. 相似文献