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1.
Masafumi Itoh Osamu Sakurada Minoru Hashiba Kouichi Hiramatsu Yukio Nurishi 《Journal of Materials Science》1996,31(12):3321-3324
An average shell volume occupied in the adsorption layer on alumina by a polyacrylic acid ammonium salts molecule (PAA) defined as the average area occupied by an adsorbed PAA on alumina multiplied by the average thickness of the water layer at the limit of thickening, has been calculated from the adsorbed amount of PAA and from the flow points of alumina in the presence of PAA of different molecular weights. A steric effect of the PAA dispersant on the dispersion of alumina resulted in a flow with no yield stress. This was due to the change of the extension of PAA in the adsorption shell from a sphere to an ellipsoid with a long axis which exceeded the effective distance that the van der Waals attraction force reaches at a molecular weight for the PAA of between 10 000–20 000. 相似文献
2.
Takakazu Yamamoto Kouichi ShiraishiMahmut Abla Isao YamaguchiL.“Bert” Groenendaal 《Polymer》2002,43(3):711-719
Neutral and non-doped poly(3,4-ethylenedioxythiophene), PEDOTh(Ni), and its hexyl derivative, PEDOTh-C6(Ni), have been prepared by organometallic dehalogenation polycondensation of 2,5-dichloro-3,4-ethylenedioxythiophene and its hexyl derivative with a zerovalent nickel complex. PEDOTh-C6(Ni) was soluble in organic solvents and 1H NMR data indicated that it had an Mn of 11,000. MALDI-TOF mass analysis of PEDOTh(Ni) gave Mn and Mw of about 1700 and 2400, respectively. PEDOTh-C6(Ni) showed a UV-Vis absorption peak at 546 nm in CHCl3. Electrochemical oxidation of PEDOTh-C6(Ni) started at about −0.40 V vs Ag+/Ag and gave a peak at 0.20 V vs Ag+/Ag. Chemical and electrochemical oxidation (or p-doping) of PEDOTh-C6(Ni), both in solutions and in a solid state, led to weakening of the original π-π∗ peaks and rise of new peak(s) in a region of 800-1500 nm. The p-doping of PEDOTh-C6(Ni) caused not only a decrease in the intensity of 1H NMR signals of the bridging ethylene hydrogens but also a decrease in that of the hexyl side chain, suggesting a strong interaction of the p-dopant with the side chain. NMR data of poly(3-methoxythiophene-2,5-diyl) also supported an assumption that p-doping brings about a severe change in electronic state of the substituent attached to the polythiophene main chain. PEDOTh(Ni) had a density of 1.71 g cm−3; the molecular packing mode of PEDOTh(Ni) is discussed based on the density of the polymer and its XRD data. 相似文献
3.
Akira Ishizaki Kazuhiko Takasaki Shoji Shimomura Kouichi Masaki Kanji Kitazawa 《Electrical Engineering in Japan》1996,116(5):128-137
Although brushless resolvers have been used widely as angular position transducers, they are expensive due to their intricate construction, involving a rotary transformer to supply the exciting coils wound on the rotor poles with the current. It is shown theoretically in this paper that the resolver without rotary transformer or brushes can be realized by simple construction, which consists of the stator core with both 4-poles exciting windings and 2-poles output ones and the rotor core carrying no windings. In this resolver the rotor core has minimum gap at one side and a maximum gap at another side of the diameter. It is characterized by an outer surface form that makes the fluctuation part of gap permeance very in proportion to cos θ, where θ represents the angular position of a point in the air gap with respect to the origin on the rotor, the point of minimum air gap. The method determining the rotor form to embody the aforementioned gap permeance variation is also shown. It has been confirmed not only by simulation but also experiment that the 2-phase output voltages of a model designed based on the theory have sinusoidal waveforms with very small harmonic contents. Moreover, the rotor position detected by processing the output voltages through the conventional resolver/digital converter was within acceptable engineering accuracy. 相似文献
4.
Masahiro Takehara Ippei Yoshimura Kouichi Takizawa Ryonosuke Yoshida 《Journal of the American Oil Chemists' Society》1972,49(3):157-161
Long chain N-acylglutamic acid was prepared in a high yield by a reaction of glutamic acid with fatty acid chloride in a mixed
solvent of water and a water miscible organic solvent such as acetone, methyl ethyl ketone, dioxane, tetrahydrofuran,t-butyl alcohol or cyclohexanone. In this reaction the composition of the mixed solvent influenced the yield of N-acylated
glutamic acid and the best yield was obtained when the reaction was carried out in the mixed solvent comprising 30–60% v/v
of the organic solvent. Long chain N-acylaspartic acid was also obtained in a high yield by the same method. As the other
method to obtain N-lauroyl-D L-glutamic acid, it was examined that N-acyl-α-aminoglutarodinitrile which was obtained by a reaction of α-aminoglutarodinitrile
with fatty acid chloride was hydrolyzed with an aqueous alkaline solution. The salts of long chain N-acylglutamic acid are
known as the surface active agents that react mildly on the human skin. 相似文献
5.
Cholesterol having a reactive hydroxyl group at C3-position can react with fatty acids to give the corresponding cholesteryl esters. Most of the natural cholesteryl esters consist of straight alkyl chain fatty acids with a high melting point. In oleochemistry it is well known that alkyl branched fatty acids, which are derived from petroleum or the fat and oil industry, have low melting points (mp.) and are chemically more stable if they are saturated acids. We designed alkyl branched fatty acid cholesteryl esters by means of common esterification and found some esters having a low mp. (mostly as a liquid). They had no irritative effect on both animal and human skin. They showed characteristic emulsification properties, namely the formation of either O/W or W/O emulsion coexistence together with other lipid components. Applying them onto human skin, they were able to penetrate towards the stratum corneum and improve the water-retaining ability and the barrier function of the stratum corneum. Based on these properties we have been applying the alkyl branched fatty acid cholesteryl ester, especially the methyl branched isostearic acid cholesteryl ester (IS-CE), to a shampoo and a rinse as hair cosmetics, skin care cosmetics and bath-additive products in the past decade. 相似文献
6.
Kenji Imamoto Jianying Zhou Kouichi Sakurai 《International Journal of Information Security》2008,7(6):383-394
Certified email is a system which enables a sender to prove a receiver’s receipt of email. Such a system can be used for applications
related to electronic commerce on the Internet. This paper considers a situation where a sender or a receiver wants to change
his/her mind due to the change of mail content value (e.g., stock, auction, gambling) during the transaction. We point out
that no traditional certified email systems have been designed for such a case, thus one of the participants can be at a disadvantage.
To avoid this problem, we propose an evenhanded certified email system in which each participant can change his/her choice,
either cancel or finish the transaction, at any time during the transaction.
相似文献
Kouichi SakuraiEmail: |
7.
An advanced coded imaging system is described, and some results of phantom experiments are presented. The advanced method uses a pair of coherent codes (+ 1 and -1 codes) and has many advantages compared with conventional ones. One of the greatest advantages is that there are no sidelobes in the focal plane and only a few in other planes. Therefore, when an object can be regarded as two-dimensional, it is perfectly reconstructed with high detecting efficiency, and this is successfully simulated by a thyroid phantom with 99mTc. Moreover, this system has an ability to reconstruct tomograms, which is also shown by using ring phantoms piled on one another with some cold spots in their shells. From these experimental results it may be concluded that the new system is useful for practical applications, for example, to nuclear medicine. 相似文献
8.
Yuichiro Kanno Nao Saito Naoya Yamashita Kazuki Ota Ryota Shizu Takuomi Hosaka Kiyomitsu Nemoto Kouichi Yoshinari 《International journal of molecular sciences》2022,23(20)
Cancer stem cells (CSCs) contribute to the drug resistance, recurrence, and metastasis of breast cancers. Recently, we demonstrated that HER2 overexpression increases mammosphere formation via the activation of aryl hydrocarbon receptor (AHR). In this study, the objective was to identify the mechanism underlying mammosphere maintenance mediated by HER2 signaling-activated AHR. We compared the chromatin structure of AHR-knockout (AHRKO) HER2-overexpressing MCF-7 (HER2-5) cells with that of wild-type HER2-5 cells; subsequently, we identified TP63, a stemness factor, as a potential target gene of AHR. ΔNp63 mRNA and protein levels were higher in HER2-5 cells than in HER2-5/AHRKO cells. Activation of HER2/HER3 signaling by heregulin treatment increased ΔNp63 mRNA levels, and its induction was decreased by AHR knockdown in HER2-5 cells. The results of the chromatin immunoprecipitation assay revealed an interaction between AHR and the intronic region of TP63, which encodes ΔNp63. A luciferase reporter gene assay with the intronic region of TP63 showed that AHR expression increased reporter activity. Collectively, our findings suggest that HER2-activated AHR upregulates ΔNp63 expression and that this signaling cascade is involved in CSC maintenance in HER2-expressing breast cancers. 相似文献
9.
Konishi T Akaki K Hatano K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2008,49(4):266-271
A simple method was developed for the analysis of hyoscyamine and scopolamine in human serum and urine using liquid chromatography with tandem mass spectrometry (LC/MS/MS). Hyoscyamine and scopolamine in serum and urine were cleaned up with an Oasis HLB cartridge and a PSA cartridge. The LC separation was carried out on an ODS column, using linear gradient elution with 5 mmol/L IPCC-MS3-methanol as the mobile phase. The mass spectral acquisition was done in the positive ion mode by applying selected reaction monitoring (SRM). The recoveries of hyoscyamine and scopolamine were 86.0-105% from human serum and urine fortified at 0.2 ng/mL and 10 ng/mL. The detection limits of hyoscyamine and scopolamine were 0.02 ng/mL. Four serum and three urine samples of humans poisoned by eating Datura innoxia Mill. were analyzed by this method. Hyoscyamine and scopolamine were detected at the levels of 0.45-3.5 ng/mL in all serum samples and 170-670 ng/mL in all urine samples. 相似文献
10.
Kotaka A Bando H Kaya M Kato-Murai M Kuroda K Sahara H Hata Y Kondo A Ueda M 《Journal of Bioscience and Bioengineering》2008,105(6):622-627
Three beta-glucosidase- and two endoglucanase-encoding genes were cloned from Aspergillus oryzae, and their gene products were displayed on the cell surface of the sake yeast, Saccharomyces cerevisiae GRI-117-UK. GRI-117-UK/pUDB7 displaying beta-glucosidase AO090009000356 showed the highest activity against various substrates and efficiently produced ethanol from cellobiose. On the other hand, GRI-117-UK/pUDCB displaying endoglucanase AO090010000314 efficiently degraded barley beta-glucan to glucose and smaller cellooligosaccharides. GRI-117-UK/pUDB7CB codisplaying both beta-glucosidase AO090009000356 and endoglucanase AO090010000314 was constructed. When direct ethanol fermentation from 20 g/l barley beta-glucan as a model substrate was performed with the codisplaying strain, the ethanol concentration reached 7.94 g/l after 24 h of fermentation. The conversion ratio of ethanol from beta-glucan was 69.6% of the theoretical ethanol concentration produced from 20 g/l barley beta-glucan. These results showed that sake yeast displaying A. oryzae cellulolytic enzymes can be used to produce ethanol from cellulosic materials. Our constructs have higher ethanol production potential than the laboratory constructs previously reported. 相似文献