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101.
Y Katsuragi Y Mitsui T Umeda K Otsuji S Yamasawa K Kurihara 《Canadian Metallurgical Quarterly》1997,14(6):720-724
PURPOSE: We examined the effects of phospholipids such as phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol (PI), and phosphatidic acid (PA) on human taste sensation to various substances. METHODS: The effects were evaluated psychophysically using paid volunteers. RESULTS: PA inhibited the bitterness of various substances dissolved in water without affecting sweetness, saltiness, and sourness, although its inhibitory activity was less than that of PA-LG. PI also showed inhibitory activity on bitterness, although its activity was less than PA. A soybean lecithin fraction containing high contents of PA and PI also demonstrated inhibitory activity on the bitterness of various substances. Both the incorporation of either PA or the lecithin fraction into granules containing quinine and the coating of the granules with PA or the fraction effectively inhibited the bitterness of quinine. CONCLUSIONS: The lecithin fraction is permitted for use as an additive to drugs and food and can be produced on an industrial scale. It is expected that the lecithin fraction will be used safely as a bitterness inhibitor for practical applications. 相似文献
102.
THz Induced Nonlinear Effects in Materials at Intensities above 26 GW/cm<Superscript>2</Superscript>
A. Woldegeorgis T. Kurihara B. Beleites J. Bossert R. Grosse G. G. Paulus F. Ronneberger A. Gopal 《Journal of Infrared, Millimeter and Terahertz Waves》2018,39(7):667-680
Nonlinear refractive index and absorption coefficient are measured for common semiconductor material such as silicon and organic molecule such as lactose in the terahertz (THz) spectral regime extending from 0.1 to 3 THz. Terahertz pulses with field strengths in excess of 4.4 MV/cm have been employed. Transmittance and the transmitted spectrum were measured with Z-scan and single shot noncollinear electro-optic pump-probe techniques. The THz-induced change in the refractive index (Δn) shows frequency-dependence and a maximum change of \(-~0.128\) at 1.37 THz in lactose and up to \(+~0.169\) at 0.15 THz in silicon was measured for a peak incident THz intensity of 26 GW/cm2. Furthermore, the refractive index variation shows a quadratic dependence on the incident THz field, implying the dominance of third-order nonlinearity. 相似文献
103.
A polypropylene film was stretched at 100–160°C., quenched to room temperature, and then restretched at the same temperature perpendicularly to the first stretching. The reorientation behavior was investigated by using optical and x-ray methods. During the restretching the monoaxial orientation caused by the stretching is converted into a new monoaxial orientation through a balanced state, where npp = nps < nss. The more or less parallel orientation to the film surface of the polypropylene molecules, brought about by the first stretching, proceeds further on restretching. nss is a linear function of the degree of stretching in area vA. The inclination of this line is independent of the type of deformation, stretching, or restretching, provided the temperature is kept constant. At 160°C. the plot of nss versus thickness is less steep than it is at 100 or 130°C. The overall reorientation apparently proceeds according to Kratky's first deformation law. The x-ray pattern of a res?tretched film is a four-point diagram which indicates the existence of a pair of reorientation axes inclined symmetrically against the stretching axis. The inclination grows larger with restretching, and the axes merge into the restretching axis at extreme restretching. This phenomenon is less pronounced when the restretching is carried out at higher temperatures. The density of the restretched film is determined mainly by the stretching temperature, but extreme restretching has a tendency to lower it very slightly. 相似文献
104.
The ring‐shaped styrene‐butadiene rubbers (SBRs) test pieces ran on a rotating stainless‐steel ring using an abrasion tester to evaluate the changes in the mechanical properties, such as the tensile storage modulus and tan δ values, the modulus at 300% elongation, and the strength and extension ratio at the breaking point, after a mechanical aging process. The surface of the SBR test pieces and the formed rubber debris after the running experiment was investigated using scanning electron microscopy. A change in the crosslinking density of the SBRs and the analysis of the isolated free polymers showed the occurrence of bond scission of the copolymer chains. On the other hand, the mechanical properties of whole SBR samples showed only a small change during the mechanical aging test. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
105.
Masaki Murata Takeo Hoshi Isao Matsuoka Takuya Nankawa Masato Kurihara Hiroshi Nishihara 《Journal of Inorganic and Organometallic Polymers》2000,10(4):209-219
The reaction of CpCo(PPh3)2, in which Cp=
5-cyclopentadienyl, with a -conjugated diacetylene, FcCC–o-C6H4–CCFc, in which Fc=ferrocenyl, was found to give a cyclobutadienecobalt mononuclear complex, {
4-C4Fc2(o-FcC6H4)2}CoCp (1), the crystal structure of which was determined by X-ray crystallography. In contrast, the reaction of CpCo(PPh3)2 with FcCC–p-C6H4–CCFc affords a cyclobutadienecobalt polymer, [p-C6H4(
4-C4Fc2)CoCp]
n
(2). The monocobalt complex 1 shows reversible 1e– and 3e– redox waves at E
0=0.116 and 0.350 V vs Ag/Ag+, and the polymer complex 2 shows two chemically reversible redox waves at E
0=0.143 and 0.219 V for the oxidation of the ferrocenyl moieties in the cyclic voltammogram. Crystal data are as follows: (1, C65H49CoFe4), triclinic, space group P\={1} (No. 2), a=13.547(4), b=16.197(4), c=11.763(4) Å, =106.79(2), =97.93(3), =97.12(3), V=2410(1) Å3, Z=2. 相似文献
106.
Kenji Ochi Yoshihisa Kato Tohru Saito Kiyofumi Kurihara Kazuo Kojima 《Korean Journal of Chemical Engineering》1997,14(5):365-368
A newly developed laser light scattering technique was used for the determination of mutual solubilities in the aniline+cydohexane
system at moderate pressures. The liquid-liquid equilibria (LLE) were measured from the region of solid-liquid equilibria
(SLE) to the upper critical solution temperature. Freezing points in this system were determined by a cooling curve method.
The solubility data were correlated with the NRTL equation. 相似文献
107.
Hiromichi Aono Takaaki Nishida Masato Kurihara Masatomi Sakamoto Yoshihiko Sadaoka 《Ceramics International》2012,38(3):2333-2338
New heteronuclear (NH4)REIII[FeII(CN)6]·nH2O complexes (RE = La, Ce, Pr, Nd, Sm, Gd, Dy, Y, Er, Lu) were synthesized and their thermal decomposition products were investigated. The crystal structure of (NH4)RE[FeII(CN)6]·nH2O would be a hexagonal unit cell (space group: P63/m), which was the same as that of La[FeIII(CN)6]·5H2O. The hydration number n = 4 was estimated by TG results for all the RE complexes. The lattice constants depended on the ionic radius of the RE3+ ion for the heteronuclear complexes. The single phase of the perovskite type materials was directly obtained by decomposition of the heteronuclear complexes for RE = La, Pr, Nd, Sm, and Gd. A mixture of CeO2 and Fe2O3 was formed for RE = Ce because of its oxidation to Ce4+. In the case of RE = Dy, Y, Er, and Lu complexes, the perovskite type materials formed at higher temperature via. mixed oxides such as RE2O3 and RE4Fe5O13 due to the small RE3+ ionic radius. 相似文献
108.
Hiroko Yamashita Prof. Makoto Oba Dr. Takashi Misawa Prof. Masakazu Tanaka Dr. Takayuki Hattori Dr. Mikihiko Naito Dr. Masaaki Kurihara Dr. Yosuke Demizu 《Chembiochem : a European journal of chemical biology》2016,17(2):137-140
Two types of cationic cyclic α,α‐disubstituted α‐amino acids: Api (which possesses a lysine mimic side chain) and ApiC2Gu (which possesses an arginine mimic side chain), were developed. These amino acids were incorporated into an arginine‐based peptide sequence [(l ‐Arg‐l ‐Arg‐dAA)3: dAA=Api or ApiC2Gu], and the relationship between the secondary structures of the resulting peptides and their ability to pass through cell membranes was investigated. The peptide containing ApiC2Gu formed a stable α‐helical structure and was more effective at penetrating cells than the nonhelical Arg nonapeptide (R9). Furthermore, the peptide was able to deliver plasmid DNA into various types of cells in a highly efficient manner. 相似文献
109.
L Kulakova A Galkin T Kurihara T Yoshimura N Esaki 《Canadian Metallurgical Quarterly》1999,65(2):611-617
The gene encoding serine alkaline protease (SapSh) of the psychrotrophic bacterium Shewanella strain Ac10 was cloned in Escherichia coli. The amino acid sequence deduced from the 2,442-bp nucleotide sequence revealed that the protein was 814 amino acids long and had an estimated molecular weight of 85,113. SapSh exhibited sequence similarities with members of the subtilisin family of proteases, and there was a high level of conservation in the regions around a putative catalytic triad consisting of Asp-30, His-65, and Ser-369. The amino acid sequence contained the following regions which were assigned on the basis of homology to previously described sequences: a signal peptide (26 residues), a propeptide (117 residues), and an extension up to the C terminus (about 250 residues). Another feature of SapSh is the fact that the space between His-65 and Ser-369 is approximately 150 residues longer than the corresponding spaces in other proteases belonging to the subtilisin family. SapSh was purified to homogeneity from the culture supernatant of E. coli recombinant cells by affinity chromatography with a bacitracin-Sepharose column. The recombinant SapSh (rSapSh) was found to have a molecular weight of about 44,000 and to be highly active in the alkaline region (optimum pH, around 9.0) when azocasein and synthetic peptides were used as substrates. rSapSh was characterized by its high levels of activity at low temperatures; it was five times more active than subtilisin Carlsberg at temperatures ranging from 5 to 15 degreesC. The activation energy for hydrolysis of azocasein by rSapSh was much lower than the activation energy for hydrolysis of azocasein by the subtilisin. However, rSapSh was far less stable than the subtilisin. 相似文献
110.
H Morita H Kurihara T Sugiyama C Hamada Y Kurihara T Shindo Y Oh-hashi Y Yazaki 《Canadian Metallurgical Quarterly》1999,19(2):298-302
Methionine synthase and 5,10-methylenetetrahydrofolate reductase (MTHFR) sequentially catalyze the remethylation of homocysteine to methionine. A point mutation in the encoding region of the methionine synthase gene, which results in substitution of an aspartic acid for a glycine residue (D919G), has been identified in patients of the cblG genetic complementation group; these patients exhibit significantly decreased methionine synthase activity. Nevertheless, the D919G mutation has also been reported to be common in the general population. In this study, we analyzed the distribution of methionine synthase D/G polymorphism in the Japanese population and examined the extent to which it is associated with altered homocysteine metabolism and late-onset vascular diseases. We studied 215 patients with coronary artery disease, 251 patients with histories of ischemic stroke, and 257 control subjects. The methionine synthase genotype was analyzed by polymerase chain reaction followed by HaeIII digestion; allele frequencies for the D919G variant of the enzyme proved to be similar in all 3 subject groups (control subjects, 0.17; coronary artery disease patients, 0. 17; and ischemic stroke patients, 0.19). Furthermore, in patients with ischemic stroke, plasma levels of homocyst(e)ine and folate were similar, irrespective of methionine synthase genotype. Thus, the methionine synthase D919G mutation was found to be common in the Japanese general population, and it appears unlikely that this polymorphism has a major effect on homocysteine metabolism and/or the onset of vascular diseases. 相似文献