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排序方式: 共有896条查询结果,搜索用时 15 毫秒
31.
Kurokawa M Masuda Y Noda M Usuda M Takeda S Hasegawa M Homma Y Sugano M 《Journal of oleo science》2008,57(1):35-45
In a placebo-controlled double-blind study, we examined the effects of dressing containing plant sterol (PS) on blood lipids and the safety in Japanese borderline or mildly hypercholesterolemic subjects. Fifty-nine subjects [total cholesterol (TC) concentration > or = 200 mg/dL] were randomly divided into two groups and were given daily 15 g of dressing containing 800 mg of PS [PS(+)-group] or without PS [PS(-)-group] for 12 weeks. Every 4 weeks, fasting blood was examined and subjective symptoms were analyzed. Serum TC, low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (ApoB) concentrations did not change in the PS(-)-group, while TC and ApoB significantly decreased in the PS(+)-group at 8 and 12 weeks and LDL-C at 4, 8 and 12 weeks. Moreover, serum TC, LDL-C and ApoB concentrations were significantly lower than those of PS(-)-group at 8 and 12 weeks. Other laboratory tests were all in normal ranges and no adverse events were observed. The results indicated that PS-containing dressing decreased serum TC, LDL-C and ApoB concentrations in borderline or mildly hypercholesterolemic subjects. It is therefore proved that the dressing containing PS is helpful in maintaining blood cholesterol level normal and hence, the health of Japanese. 相似文献
32.
Takayuki Komatsu Kazuya Aida Tuyoshi Honma Yasuhiko Benino Ryuji Sato 《Journal of the American Ceramic Society》2002,85(1):193-199
The structural relaxation kinetics at the glass transition in tellurium oxide (TeO2 )-based glasses has been examined from viscosity and heat-capacity measurements to clarify the features of the structural relaxation in fragile oxide glass-forming liquids. A large decoupling between enthalpy relaxation and viscous flow, i.e., a large discrepancy between the activation energies for the enthalpy relaxation (recovery), Δ H , and viscous flow, E η , has been demonstrated in TeO2 -based glasses. The values in x K2 O· x MgO·(100 − 2 x )TeO2 glasses, for example, are ∼919–1051 kJ/mol for Δ H and ∼ 577–701 kJ/mol for E η , given the ratio of Δ H/E η ≈ 1.44–1.59. Some viscosity and heat-capacity data (all data have been reported previously) obtained from similar experiments in Sb2 O3 –B2 O3 glasses belonging to the category of strong glass-forming liquids have been reanalyzed in this paper for comparison; a strong coupling was found to exist between Δ H and E η , i.e., Δ H/E η ≈ 0.98–1.18. An origin of decoupling between Δ H and E η in fragile glass-forming systems such as TeO2 -based glasses has been discussed by considering the glass structure model for fragile glasses; strongly bonded correlated (highly constrained) regions are surrounded or connected by weakly bonded noncorrelated (unconstrained) parts. 相似文献
33.
Preparation of sharp-melting hard palm midfraction and its use as hard butter in chocolate 总被引:1,自引:0,他引:1
Satsuki Hashimoto Toru Nezu Hiroshi Arakawa Tomonori Ito Shoji Maruzeni 《Journal of the American Oil Chemists' Society》2001,78(5):455-460
Preparation of hard palm midfractions (PMF) and its use as a cocoa butter equivalent ingredient were studied. Hard PMF is
obtained by multistep fractionation of palm oil involving dry fractionation (DF) and/or solvent fractionation (SF), usually
using hexane or acetone. From our experience, in acetone, a polar solvent, symmetrical 1,3-disaturated triacylglycerols tend
to selectively crystallize more than nonsymmetrical 1,2- or 2,3-disaturated triacylglycerols, making it suitable for obtaining
the solid midfraction. Unfortunately, triacylglycerols are very soluble in hexane, and temperatures at least 15 degrees lower
than those required for acetone must be used for equivalent crystal yields. On the other hand, DF is a less expensive and
safer process. Thus, multistep fractionation combining DF and SF using acetone was developed to achieve sufficient removal
of high-melting components, and further enrichment of 1,3-dipalmitoyl-2-oleoylglycerol and the hard PMF was obtained by triple-step
fractionation of palm olein or double-step fractionation of soft PMF. Compared to conventional hard PMF, this hard PMF had
a steeper melting curve and better snapping and sharp-melting qualities when used in chocolate. Heat resistance of the hard
PMF chocolate was similar to the conventional hard PMF chocolate, and its bloom resistance could be improved by adding polyglycerol
fatty acid esters. 相似文献
34.
Seiji Inaba Yasuhiko Benino Shinji Kohara Hideo Hosono Setsuro Ito 《Journal of the American Ceramic Society》2020,103(6):3631-3641
Orientation anisotropy, which is well known in organic polymers with appropriate network structures, is less common in oxide glasses. We present the intermediate-range order in anisotropic alkali metaphosphate glass which consists of oriented PO4 tetrahedral chains and intervening alkali cations along the elongation direction. The X-ray total structure factor S(Q) indicates that the inter-chain spacing depends on the size of alkali cations and varies from 5.03 to 6.28 Å. The mixed alkali effect is primarily related to an increase of the separation. The total correlation function T(r) provides the first definite evidence that the anisotropic structure is composed of phosphorus-bridging oxygen bonds (P–OB) lying along the elongation direction and phosphorus-non-bridging oxygen bonds (P–OT) oriented perpendicular to the elongation direction. The present result unveils fundamental aspects of the anisotropic structure of an oxide glass and provides essential information for the development of oxide glasses to control structural anisotropy. 相似文献
35.
Liposome‐Based in Vitro Evolution of Aminoacyl‐tRNA Synthetase for Enhanced Pyrrolysine Derivative Incorporation 下载免费PDF全文
Dr. Atsuko Uyeda Dr. Takayoshi Watanabe Dr. Yasuhiko Kato Prof. Hajime Watanabe Prof. Tetsuya Yomo Prof. Takahiro Hohsaka Dr. Tomoaki Matsuura 《Chembiochem : a European journal of chemical biology》2015,16(12):1797-1802
Methanosarcina species pyrrolysyl‐tRNA synthetase (PylRS) attaches Pyl to its cognate amber suppressor tRNA. The introduction of two mutations (Y384F and Y306A) into PylRS was previously shown to generate a mutant, designated LysZ‐RS, that was able to attach N‐benzyloxycarbonyl‐L ‐lysine (LysZ) to its cognate tRNA. Despite the potential of LysZ derivatives, further LysZ‐RS engineering has not been performed; consequently, we aimed to generate LysZ‐RS mutants with improved LysZ incorporation activity through in vitro directed evolution. Using a liposome‐based in vitro compartmentalization (IVC) approach, we screened a randomly mutagenized gene library of LysZ‐RS and obtained a mutant that showed increased LysZ incorporation activity both in vitro and in vivo. The ease and high flexibility of liposome‐based IVC should enable the evolution of not only LysZ‐RS that can attach various LysZ derivatives but also of other enzymes involved in protein translation. 相似文献
36.
Takahiro Ohkubo Eiji Tsuchida Kenzo Deguchi Shinobu Ohki Tadashi Shimizu Toshiya Otomo Yasuhiko Iwadate 《Journal of the American Ceramic Society》2018,101(3):1122-1134
It remains a challenge to establish structural models of multicomponent oxide glass systems. In this study, we have investigated 68.3SiO2–16.1B2O3–4.2Al2O3–11.4Na2O glass and melt structures by ab initio molecular dynamics (AIMD) simulations. The atomic configurations obtained from AIMD simulations were validated against 17O solid‐state NMR spectrum under 24.0 T and neutron diffraction data, and excellent agreement was achieved. The bond lengths, angles, and coordination geometries were statistically analyzed for each atomic species. Here we particularly address the role of minor atomic species such as five‐coordinate Si (SiV) and Al (AlV). The SiV–O bond lengths and O–SiV–O angle distribution in the glass indicated 1.718 Å and three peaks at 90°, 120°, and 175°, which are assigned to a coordination geometry of the trigonal bipyramidal structure. Ring statistic analysis revealed that SiV and AlV were found to preferentially contribute to the formation of small ring sizes. 相似文献
37.
Yasuhiko Otsuki Toshihisa Kajiwara Kazumori Funatsu 《Polymer Engineering and Science》1997,37(7):1171-1181
Numerical viscoelastic simulations were carried out using a K-BKZ type of separable integral constitutive equation. Both reversible and irreversible models were tried for several types of damping functions to calculate the annular extrudate behavior of high-density polyethylene (HDPE). There are two aims in this study; first, to clarify the properties of these dumping functions, and second, to investigate the influence of rheological characteristics on annular extrudate swell. In these numerical simulations, relaxation spectrum and shear viscosity were fixed, and the other characteristics were varied. The reversional response of the damping function mainly has an effect on the magnitude of the area swell even if the die is straight. The irreversible model expresses the experimental results of annular extrudate swell better than the reversible model. The accurate fitting of N1 by the damping model is important for predicting it. The magnitude of N1 predicted from the Wagner exponential model is lower than that of the PSM model, and the area swell shows the same tendency as N1. A modified PSM model that allows the N1 curve to shift can fit the magnitude of area swell. The relationship between the diameter and thickness of the extrudate depends on N2/N1, and it was estimated by simple linear elasticity of solids. The time dependent viscosity varies with the type of damping function, and it influences the time-dependent swell. 相似文献
38.
Kazuya Aida Yasuhiko Benino Vesselin Dimitrov Takayuki Komatsu Ryuji Sato 《Journal of the American Ceramic Society》2000,83(5):1192-1198
The kinetics of enthalpy relaxation (recovery) at the glass transition in x K2 O·(20− x )MgO·80TeO2 glasses has been examined from heat capacity measurements using differential scanning calorimetry to clarify the features of the structural relaxation in ternary TeO2 -based glasses. Ternary glasses such as 10K2 O·10MgO·80TeO2 show high thermal resistance against crystallization compared with binary glasses. The degree of fragility m estimated from the activation energy for viscous flow E η and the glass transition temperature T g is m = 55–62, indicating a fragile character in TeO2 -based glasses. Large heat capacity changes of 43.1–48.2 J·mol−1 ·K−1 are also observed at the glass transition. The activation energy for enthalpy relaxation Δ H is evaluated from the cooling rate dependence of the limiting fictive temperature, and values of Δ H = 897–1268 kJ·mol−1 are obtained. Negative deviation from additivity in Δ H is also observed. Values of the Kovacs–Aklonis–Huchinson–Ramos (KAHR) parameter θ estimated from Δ H and T g are 0.33–0.42 K−1 . It has been proposed that ternary glasses have more homogeneous and constrained glass structure compared with binary glasses. 相似文献
39.
Tomoo Yamamura Tomonori Mori Ki Chul Park Yasuhiko Fujii Hiroshi Tomiyasu 《The Journal of Supercritical Fluids》2009,51(1):43-49
Catalytic reduction gasification in the presence of ruthenium(IV) dioxide (RuO2) in supercritical water was used to decompose intractable biomass. The gasification of model biomass samples (glucose, cellulose, and heterocyclic compounds), and low-purity biomass samples obtained from a paper-recycling facility (paper sludge) and from a sewage treatment plant (sewage sludge) were studied. In clear contrast to another catalysts, the RuO2 catalyst completely gasified cellulose to produce mainly hydrogen, methane, and carbon dioxide under various conditions (e.g., 673 K at 30 MPa and 773 K at 50 MPa). As for heterocyclic compounds, nitrogen compounds did not deactivate the RuO2 catalyst; the gasification of carbazole proceeded completely. Furthermore, paper sludge was almost completely decomposed in supercritical water with RuO2 at 723 K. 相似文献
40.
Makoto Miyazawa Yasuhiko Irie Kazuki Kashimoto Naoko Nishina Mitsuru Kondo Sachiko Yasue Kenji Maeda Fumio Uchida 《Inorganic chemistry communications》2009,12(4):336-339
Three new complexes, [Zn(dbsf)2(dmf)2] · 5.5dmf (dbsf = 4,4′-sulfonyldibenzoate) (1β), [Cu(tdsa)(phen)2] · 1.5EtOH (tdsa = 5,5′-thiodisalicylate, phen = 1,10-phenanthroline) (2), and [Cu(sdp)(phen) · Cu(Hsdp)(phen)(CH3COO)] · 3EtOH (sdp = 4,4′-sulfonyldiphenolate) (3) were prepared and structurally characterized. Complex 1β shows a one-dimensional coordination framework constructed from bridges between Zn(II) centers with two ligands. Complex 2 is a monomeric complex, which assembles by π–π interactions. Complex 3 shows a unique two-dimensional coordination framework that is constructed from two Cu(II) centers, sdp, and Hsdp. The redox properties of these three complexes were characterized by solid-state cyclic voltammetry. Complexes 1β and 3 show irreversible reduction waves because of the reduction of their sulfone sites. Complex 2 shows an irreversible oxidation wave because of oxidation of the sulfide site. 相似文献