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101.
Daisuke Saio Toru Amaya Toshikazu Hirao 《Advanced Synthesis \u0026amp; Catalysis》2010,352(13):2177-2182
The hybrid consisting of gold nanoparticles and poly(2‐methoxyaniline‐5‐sulfonic acid), which works as a redox mediator for transferring protons and electrons, catalyzed the oxidation reaction of various alcohols in water under molecular oxygen. 相似文献
102.
103.
Yang Gao Junya Iihama Daiki Hamana Ryo Iwasaki Sawao Honda Toru Asaka Munni Kumari Tomokatsu Hayakawa Samuel Bernard Philippe Thomas Yuji Iwamoto 《International Journal of Applied Ceramic Technology》2023,20(2):768-779
A series of β-SiAlON:Eu2+ phosphors were synthesized from single-source precursors, perhydropolysilazane chemically modified with Al(OCH(CH3)2)3, AlCl3, and EuCl2. The single-source precursors were converted to β-SiAlON:Eu2+ phosphors by pyrolysis under flowing N2 or NH3 at 1000°C, followed by heat treatment at 1800°C under an N2 gas pressure at 980 kPa. By varying the molar ratio of the chemical modifiers, β-SiAlON:Eu2+ with the compositions close to the theoretical ones expressed as Si6−zAlzOz−2yN8−z+2y:yEu2+ were synthesized, where the z values and Eu2+ contents were controlled in the ranges of .44–.78 and .35–1.48 mol%, respectively. The polymer-derived β-SiAlON:Eu2+ phosphors exhibited green emission under excitation at 460 nm attributed to the 4f7–4f6(7f3)5d1 transition of dopant Eu2+. High-angle annular dark-field-scanning transmission microscopy analysis confirmed that the doped-Eu2+ existed interstitially within the channels along the c axis of host β-SiAlON. Compared with the conventional powder metallurgy route, the polymer-derived ceramic route in this study offers some advantages in the grain growth of host β-SiAlON and photoluminescence properties in terms of green emission intensity under excitation at 460 nm, and the highest intensity was achieved for the polymer-derived β-SiAlON:Eu2+ with z = .64 and .37 mol% Eu2+. 相似文献
104.
Role of Heavy Meromyosin in Heat‐Induced Gelation in Low Ionic Strength Solution Containing l‐Histidine 下载免费PDF全文
Toru Hayakawa Yuri Yoshida Masanori Yasui Toshiaki Ito Jun‐ichi Wakamatsu Akihito Hattori Takanori Nishimura 《Journal of food science》2015,80(8):C1641-C1645
The gelation of myosin has a very important role in meat products. We have already shown that myosin in low ionic strength solution containing l ‐histidine forms a transparent gel after heating. To clarify the mechanism of this unique gelation, we investigated the changes in the nature of myosin subfragments during heating in solutions with low and high ionic strengths with and without l ‐histidine. The hydrophobicity of myosin and heavy meromyosin (HMM) in low ionic strength solution containing l ‐histidine was lower than in high ionic strength solution. The SH contents of myosin and HMM in low ionic strength solution containing l ‐histidine did not change during the heating process, whereas in high ionic strength solution they decreased slightly. The heat‐induced globular masses of HMM in low ionic strength solution containing l ‐histidine were smaller than those in high ionic strength solution. These findings suggested that the polymerization of HMM molecules by heating was suppressed in low ionic strength solution containing l ‐histidine, resulting in formation of the unique gel. 相似文献
105.
In this paper, we study the existence of cycles of all lengths in the recursive circulant graphs, and we show a necessary and sufficient condition for the graph being pancyclic and bipancyclic. 相似文献
106.
For systems with uncertainties, lots of PID parameter tuning methods have been proposed from the view point of the robust stability theory. However, the control performance becomes conservative using robust PID controllers. In this paper, a new two‐degree‐of‐freedom (2DOF) controller, which can improve the tracking properties, is proposed for nonlinear systems. According to the proposed method, the prefilter is designed as the PD compensator whose control parameters are tuned by the idea of a memory‐based modeling (MBM) method. Since the MBM method is a type of local modeling methods for nonlinear systems, PD parameters can be tuned adequately in an online manner corresponding to nonlinear properties. Finally, the effectiveness of the newly proposed control scheme is numerically evaluated on a simulation example. Copyright © 2008 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society 相似文献
107.
Protein import into the nucleus is generally considered to involve specific nuclear localization signals (NLS) though it is becoming increasingly clear that efficient and well controlled import of proteins which lack a canonical NLS also occurs in cells. Human immunodeficiency virus type 1 (HIV-1) Vpr is one such protein which does not have an identifiable canonical NLS and yet efficiently localizes to the nuclear compartment. Here, we use confocal microscopy to demonstrate that mutations in the putative central hydrophobic helix of Vpr result in the retention of the protein in highly localized ring-like structures around the nuclear periphery with striking impairment in their ability to enter the nuclear interior. By characterizing other biological activities associated with this protein, such as its ability to incorporate into budding virions and its ability to arrest cells in G2, we show that this helical domain is specific for the nuclear translocation of the protein with very little effect on these other functions. Interestingly, however, perturbation of this helical motif also perturbs the protein's ability to augment viral replication in primary human macrophages indicating that the integrity of this secondary structure is essential for optimal infection in these non-dividing cells. 相似文献
108.
Nguyen Tien Phong Mohamed H. Gabr Le Hoai Anh Vu Minh Duc Andrea Betti Kazuya Okubo Bui Chuong Toru Fujii 《Journal of Materials Science》2013,48(17):6039-6047
In this study, core–shell rubber (CSR) nanoparticles with approximate particle size of 35 nm were used as a modifier for the epoxy polymer. The effects of various CSR contents in the epoxy matrix on mode I interlaminar fracture toughness, tensile strength, and fatigue life of the carbon fabric reinforced epoxy (CF/EP) composites were investigated. The experimental results showed that the mode I interlaminar fracture toughness at crack initiation and propagation significantly improved by 71.21 and 58.47 %, respectively, when 8.0 wt% CSR was dispersed in the epoxy matrix. The fatigue life of the modified CF/EP composites at all of CSR contents dramatically increased 75–100 times longer than that of the unmodified CF/EP composites at high cycle fatigue while tensile strength slightly increased by about 10 %. Field emission scanning electron microcopy (FESEM) observations of the fracture surfaces were conducted to explain failure mechanisms of CSR addition to the CF/EP composites. The evidences of the rubber nanoparticle debonding, plastic void growth, and microshear banding were credited for delaying the onset of matrix crack, and reducing the crack growth rate, as a result, attributed to increase in the mechanical properties of the CF/EP composites. 相似文献
109.
The enantiomeric composition of the monounsaturated triacylglycerols (TG) from cocoa butter was estimated. The monounsaturated
TG were separated into three fractions by reversed-phase high-performance liquid chromatography (HPLC), and each fraction
was subjected to the stereospecific analysis with chiral-phase HPLC. The results indicated that the major TG consisted of
equal amounts of 1-stearoyl-2-oleoyl-3-palmitoyl-sn-glycerol (SOP-sn-TG) and POS-sn-TG (47 mol%), 1,3-distearoyl-2-oleoyl-glycerol (SOS-TG) (33 mol%), and POP-TG (19 mol%). The contents of SOP-sn-TG and POS-sn-TG are 1.30 times that of the POP-TG content, and the SOS-TG content is 1.302 times that of the POP-TG content. The term “priority factor” is proposed for the ratio of the stearoyl group/palmitoyl group,
1:30 at thesn-1 andsn-3 or 1(3)-position. It shows a distinct specificity for particular fatty acids or their Coenzyme A esters in random esterification
at each position of the glycerol moiety in the biosynthesis of cocoa butter TG. 相似文献
110.
The effect of small dose of topiroxostat on serum uric acid in patients receiving hemodialysis 下载免费PDF全文
Yume Nagaoka Yoshiko Tanaka Hiroshi Yoshimoto Rie Suzuki Kakei Ryu Mio Ueda Minako Akiyama Miho Nagai Yoshitaka Miyaoka Eiichiro Kanda Shinnichi Iwai Michio Nagaoka Yoshihiko Kanno 《Hemodialysis international. International Symposium on Home Hemodialysis》2018,22(3):388-393
Introduction : Topiroxostat, a recently developed xanthine oxidase inhibitor, is expected to have fewer adverse effects than allopurinol because it has different mechanism of action from alloprinol. However, its dosage, usage and safety have not been established in patients with impaired renal function or those undergoing dialysis at the development since no studies was conducted in these patients. Methods : Cross over clinical trial using 3 months of allopurinol and topiroxostat on 27 maintain Japanese HD patients were carried out. The effects on oxidative stress status of both drugs were also evaluated by measuring oxidation reduction potential. Findings : Twenty‐five of twenty‐seven patients completed study. The mean serum uric acid levels in the topiroxostat‐treated arm was significantly lower than it in the allopurinol‐treated arm time‐dependently (P < 0.0001). Corrected oxidative stress ratio defined as biological antioxidant potential/diacron reactive oxygen metabolites was significantly increased in topiroxostat‐arm (*P = 0.0035), but not in allopurinol‐arm (P = 0.1429). No significant difference was seen in diacron reactive oxygen metabolites, biological antioxidant potential, static oxidation‐reduction potential, and capacity oxidation‐reduction potential between pre and post treatment of both drugs. Discussion : It is suggested that a low dose of topiroxostat decreased serum uric acid sufficiently to maintain it below 7.0 mg/dL in patients receiving hemodialysis. 相似文献