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51.
Supported by TGRC-KOSEF. 相似文献
52.
Global Convergence Properties of Nonlinear Conjugate Gradient Methods with Modified Secant Condition 总被引:2,自引:1,他引:1
Conjugate gradient methods are appealing for large scale nonlinear optimization problems. Recently, expecting the fast convergence of the methods, Dai and Liao (2001) used secant condition of quasi-Newton methods. In this paper, we make use of modified secant condition given by Zhang et al. (1999) and Zhang and Xu (2001) and propose a new conjugate gradient method following to Dai and Liao (2001). It is new features that this method takes both available gradient and function value information and achieves a high-order accuracy in approximating the second-order curvature of the objective function. The method is shown to be globally convergent under some assumptions. Numerical results are reported. 相似文献
53.
Shuichi Ban Yoshiki Takano Naoki Ohkubo Hisanobu Hoya Yumiko Takahashi Kouichi Takase Kazuko Sekizawa 《Hyperfine Interactions》2005,165(1-4):95-99
The transition metal phosphorus trichalcogenides MnPS3 and the FePS3 are CdCl2 type layered compounds, where the transition metal ions form a hexagonal lattice. While these compounds order anti-ferromagnetically at low temperature, the magnetic structures are different. We have reported that these mixtures Mn0.5Fe0.5PS3 is a spin glass with a glass transition temperature T g=33.7 K. Then, in this work, we report that the results of the temperature variation of the 57Fe Mössbauer spectra of FePS3 and Mn0.5Fe0.5PS3, in detail. In the anti-ferromagnetic state of FePS3, the hyperfine magnetic field H int increases with decreasing temperature and the Isomer shift I. S. increases slightly with decreasing temperature. However in Mn0.5Fe0.5PS3, the two broadened peaks are observed and the two peaks became a single peak with decreasing temperature at about 50.0 K, which is higher than T g=33.7 K. In the spin glass Mn0.5Fe0.5PS3, the Mössbauer spectra suggest that the magnetic interactions exist far above T g. 相似文献
54.
Yukio Kanda Masafumi Taira Kazuhiko Chimura Tomoyuki Takano Motoaki Sawabe 《Analytical sciences》2005,21(6):629-634
A reliable and convenient system to generate accurate and stable standard gas mixtures of various atmospheric compounds at parts-per-billion levels has been developed. The system is of simple design; the generator is a coil consisting of an inner tube of microporous polytetrafuluoroethylene (PTFE) membrane tubing and an outer tube of silicone tubing. An aqueous solution of the given compound continuously flows through the inner microporous tube and the purge gas flows through the annulus between the inner and outer tubes. In addition to the generation of gas mixtures based on Henry's law, the proposed flow-type system offers generation based on chemical reactions, leading to a distinct advantage of the availability of continuous sources of various compounds. The generation system was tested for preparing standard gas mixtures of HCHO and H2O2 on the basis of Henry's law, and those of HNO2, NO, and SO2 on the basis of chemical reactions. A stable generation of the desired low concentrations of various kinds of gas mixtures can be readily achieved by adjusting the concentration of the solution without the use of high-dilution flow. 相似文献
55.
Enhanced conformational sampling method for proteins based on the TaBoo SeArch algorithm: Application to the folding of a mini‐protein,chignolin 下载免费PDF全文
The conformational samplings are indispensible for obtaining reliable canonical ensembles, which provide statistical averages of physical quantities such as free energies. However, the samplings of vast conformational space of biomacromolecules by conventional molecular dynamics (MD) simulations might be insufficient, due to their inadequate accessible time‐scales for investigating biological functions. Therefore, the development of methodologies for enhancing the conformational sampling of biomacromolecules still remains as a challenging issue in computational biology. To tackle this problem, we newly propose an efficient conformational search method, which is referred as TaBoo SeArch (TBSA) algorithm. In TBSA, an inverse energy histogram is used to select seeds for the conformational resampling so that states with high frequencies are inhibited, while states with low frequencies are efficiently sampled to explore the unvisited conformational space. As a demonstration, TBSA was applied to the folding of a mini‐protein, chignolin, and automatically sampled the native structure (Cα root mean square deviation < 1.0 Å) with nanosecond order computational costs started from a completely extended structure, although a long‐time 1‐µs normal MD simulation failed to sample the native structure. Furthermore, a multiscale free energy landscape method based on the conformational sampling of TBSA were quantitatively evaluated through free energy calculations with both implicit and explicit solvent models, which enable us to find several metastable states on the folding landscape. © 2015 Wiley Periodicals, Inc. 相似文献
56.
Yasuko Saito Hiroshi Kamitakahara Toshiyuki Takano 《Cellulose (London, England)》2017,24(9):3659-3669
The influences of two structural modifications on the photocurrent generation performance of the Langmuir–Blodgett (LB) film of the 6-O-phthalocyaninyl cellulose derivative were investigated. These structural modifications were the substituent groups at the O-2 and O-3 positions, and the central metal of the phthalocyanine moiety. Specifically, 6-O-Zn/phthalocyaninyl- (8a) and Pd/phthalocyaninyl (8b) -2,3-di-O-myristoylcelluloses were prepared instead of 6-O-Zn/phthalocyaninyl-2,3-di-O-myristylcellulose (2). The LB monolayer film of compound 8a on an indium thin oxide electrode showed higher photocurrent generation performance than that of compound 2. This suggested that myristoyl groups (C-14 acyl groups) were more beneficial to photocurrent generation than myristyl groups (C-14 alkyl groups), as the substituent at the O-2 and O-3 positions. The LB monolayer film of compound 8b showed photocurrent generation from 500 to 700 nm, although a blue-shift in the Q-band maximum was observed. The photocurrent generation performance of compound 8b was significantly higher than that of compound 8a. This indicated that Pd was more beneficial to photocurrent generation than Zn. The film of compound 8b prepared by the horizontal lifting method showed better photocurrent generation performance than that prepared by the vertical dipping method. Consequently, compound 8b is a complementary material to the porphyrin-appended cellulose derivative (1) for photocurrent generation system. 相似文献
57.
Takano Yuichi Ishii Nobuaki Muraki Masaaki 《Central European Journal of Operations Research》2017,25(2):303-323
Central European Journal of Operations Research - In competitive bidding for project contracts, contractors estimate the cost of completing a project and then determine the bid price. Accordingly,... 相似文献
58.
Otani M Taniguchi T Sakai A Seta J Kadoyama K Nakamura-Hirota T Matsuyama S Sano K Takano M 《Applied biochemistry and biotechnology》2011,164(6):804-818
We validated the novel PhosphoQUANTI SolidBlue Complex (PQSC) dye for the sensitive fluorescent detection of phosphorylated proteins in polyacrylamide- and two-dimensional gel electrophoresis (PAGE and 2DE, respectively). PQSC can detect as little as 15.6 ng of ß-casein, a pentaphosphorylated protein, and 61.3 ng of ovalbumin, a diphosphorylated protein. Fluorescence intensity correlates with the number of phosphorylated residues on the protein. To demonstrate the specificity of PQSC for phosphoproteins, enzymatically dephosphorylated lysates of Swiss 3T3 cells were separated in 2DE gels and stained by PQSC. The fluorescence signals in these gels were markedly reduced following dephosphorylation. When the phosphorylated proteins in Swiss 3T3 cell lysates were concentrated using a phosphoprotein enrichment column, the majority of phosphoproteins showed fluorescence signals in the pI 4–5 range. Finally, we performed phosphoproteome analysis to study differences in the protein phosphorylation profiles of proliferating and quiescent Swiss 3T3 cells. Over 135 discernible protein spots were detected, from which a selection of 15 spots were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF-MS). The PQSC staining procedure for phosphoprotein detection is simple, reversible, and fully compatible with MALDI TOF-MS. 相似文献
59.
Kanda M Sasamoto T Takeba K Hayashi H Kusano T Matsushima Y Nakajima T Kanai S Takano I 《Journal of AOAC International》2011,94(3):878-885
A new, rapid, and efficient method for determining the fumagillin residues in honey was developed. The samples extracted were analyzed using LC/MS/MS. Chromatographic separation of fumagillin was performed in gradient mode on a C8 column (100 x 2.0 mm, 5 microm) at 40 degrees C. The mobile phase consisted of a mixture of 2 mM ammonium formate-0.01% formic acid solution and methanol; the flow rate was set to 0.2 mL/min. Under these conditions, it was possible to measure fumagillin and its isomers as a single peak. The sample preparation procedure used is based on the QuEChERS (quick, easy, cheap, effective, rugged, and safe) method, which is fast (approximately 30 min) and uses less organic solvent. The fumagillin was extracted with acetonitrile containing 0.1% formic acid, then purified using a solid-phase extraction method with an Oasis mixed-mode weak anion-exchange cartridge. The overall recovery of fumagillin ranged from 88.1 to 99.4%; the intra- and interassay CVs were <4.5% and <4.9%, respectively. The LOQ was 0.1 microg/kg. LC/MS/MS coupled with the QuEChERS method showed strong potential as a method for determining fumagillin residues in honey. 相似文献
60.
H. Kuramochi J. Okabayashi F. Takano M. Mizuguchi T. Manago H. Akinaga 《Surface science》2004,550(1-3):192-198
Strong magnetic poles at characteristic rectangular defects have been observed using a magnetic force microscope on a MnAs(
1 0 0) thin film with the thickness of 30 nm. The MnAs thin film was epitaxially grown on a GaAs(0 0 1) substrate. The magnetic poles were in one-arranging direction, being independent of the magnetization direction of the film. The poles were pinned at the edges of the rectangular defects until just below the Curie temperature, and formed a stable magnetic-field loop on the MnAs surface. The stability of the magnetic pole pinning shows the distinctive feature of the magnetic domain structure on the surface with a strong anisotropy, which was built in the heterostructure of MnAs and GaAs. 相似文献