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51.
52.
Tadahiko Kawai Nobutoshi Yoshimura 《International journal for numerical methods in engineering》1969,1(1):123-133
The large deflection problem of a rectangular plate is analysed by using the finite element method and employing the iteration technique. In the present study, the stiffness matrix of a rectangular plate element for bending proposed by Greene is employed, and results of numerical examples duly justifies applicability of the present method. 相似文献
53.
54.
Pertiwiningrum A Ino Y Suzuki T Iwama T Kawai K 《Journal of Bioscience and Bioengineering》2004,98(3):214-216
The cells of Streptomyces sp. YB-1 adsorbed 4-6 mg ytterbium (Yb) per g dry weight. The Yb contents of the cell wall fraction, cell-free extract, and cell membrane fraction were 11%, 2%, and 87%, respectively. The Yb content in the cell membrane fraction was 20-25 mg per g dry weight. The adsorbed Yb could be quantitatively desorbed by treating the cell membrane fraction with 1 mM EDTA and 1 M HCl at 37 degrees C for 4 h. Treatment with 1 M NaOH caused Yb desorption to some extent. Treatments with proteinase K, lysozyme, 0.5% Triton X-100, 0.4% sodium dodecyl sulfate, and 1 M NaCl did not cause Yb desorption. Elemental analysis of Yb-adsorbed materials after removal of proteins and then extraction of lipids from the membrane fraction revealed that the molar ratio of Yb and P in the materials was about 1:1. The cells and the membrane fraction could be used repeatedly as a bioadsorbent for Yb. 相似文献
55.
A new beta-agarase was purified from an agarolytic bacterium, Bacillus sp. MK03. The enzyme was purified 129-fold from the culture supernatant by ammonium sulfate precipitation, anion exchange and gel filtration column chromatographic methods. The purified enzyme appeared as a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Estimation of the molecular mass by SDS-PAGE and gel filtration gave values of 92 kDa and 113 kDa, respectively. The N-terminal amino acid sequence of the enzyme showed no homology to those of other known agarases. The optimum pH and temperature for this enzyme were 7.6 and 40 degrees C, respectively. The predominant hydrolysis product of agarose by this enzyme was neoagarotetraose, indicating the cleavage of beta-1,4 linkage. This enzyme could hydrolyze neoagarohexaose to produce neoagarotetraose and neoagarobiose; it could not hydrolyze these products. The enzyme digested agarose by endo-type hydrolysis. 相似文献
56.
Effect of grain size distribution on the strength of porous Si3N4 ceramics composed of elongated β-Si3N4 grains 总被引:1,自引:0,他引:1
C. Kawai 《Journal of Materials Science》2001,36(23):5713-5717
The grain size distributions (diameter and aspect ratio) of porous Si3N4 ceramics composed of elongated -Si3N4 grains were evaluated statistically, and their effect on the pore size distribution and the flexural strength of the porous Si3N4 was investigated. Porous Si3N4 ceramics having porosities of 27 to 43% and median pore diameters of 0.56 to 0.96 m were used as specimens. The grain diameter distribution was well correlated to the pore size distribution of the porous Si3N4 ceramics. We concluded that the strength of the porous Si3N4 ceramics increased with increasing grain length of -Si3N4 as well as with decreasing porosity. 相似文献
57.
Organometallic Bonding in an Ullmann‐Type On‐Surface Chemical Reaction Studied by High‐Resolution Atomic Force Microscopy
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Shigeki Kawai Ali Sadeghi Toshihiro Okamoto Chikahiko Mitsui Rémy Pawlak Tobias Meier Jun Takeya Stefan Goedecker Ernst Meyer 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(38):5303-5311
The on‐surface Ullmann‐type chemical reaction synthesizes polymers by linking carbons of adjacent molecules on solid surfaces. Although an organometallic compound is recently identified as the reaction intermediate, little is known about the detailed structure of the bonded organometallic species and its influence on the molecule and the reaction. Herein atomic force microscopy at low temperature is used to study the reaction with 3,9‐diiododinaphtho[2,3‐b:2′,3′‐d]thiophene (I‐DNT‐VW), which is polymerized on Ag(111) in vacuum. Thermally sublimated I‐DNT‐VW picks up a Ag surface atom, forming a C? Ag bond at one end after removing an iodine. The C? Ag bond is usually short‐lived, and a C? Ag? C organometallic bond immediately forms with an adjacent molecule. The existence of the bonded Ag atoms strongly affects the bending angle and adsorption height of the molecular unit. Density functional theory calculations reveal the bending mechanism, which reveals that charge from the terminus of the molecule is transferred via the Ag atom into the organometallic bond and strengths the local adsorption to the substrate. Such deformations vanish when the Ag atoms are removed by annealing and C? C bonds are established. 相似文献
58.
Sylwia Nowakowska Aneliia Wäckerlin Ignacio Piquero‐Zulaica Jan Nowakowski Shigeki Kawai Christian Wäckerlin Manfred Matena Thomas Nijs Shadi Fatayer Olha Popova Aisha Ahsan S. Fatemeh Mousavi Toni Ivas Ernst Meyer Meike Stöhr J. Enrique Ortega Jonas Björk Lutz H. Gade Jorge Lobo‐Checa Thomas A. Jung 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(28):3757-3763
59.
DLC films were deposited by a new pulsed DC discharge plasma chemical vapour deposition (CVD) using hydrogen and methane gas mixture. When methane concentration (Cm) i.e. CH4/(H2 + CH4) was increased from 3 to 40%, the graphitization of the carbon film increases as evident from Raman study. When Cm was increased to 30%, DLC film shows photoconducting property. The white light photoconductivity (S = Il/Id, where Il is light current and Id is dark current) measured with solar simulator under AM 1.5 condition was approximately 20 at room temperature. The photoconductivity was not clear when Cm was lower than 20%. ESR measurements also show that the electron spin density was slightly decreased with decreasing concentration of methane. Thus we can conclude here that at higher concentrations of methane at 30%, Sp2 content of the film increases and the DLC film becomes photoconducting. 相似文献
60.
A formalization of graphical processes in computer graphics systems is presented in terms of functions and their system of axioms. The concept of the viewing pipeline is formalized as operation sequence which is a sequential composition of graphical elementary operations. The formalization includes two kinds of operation sequences which are used as the formal specifications of graphics systems and display devices. In order to generate a graphics system using a display device, we introduced the concept of functionality-preserving transformation of operation sequences in terms of various types of commutations among primitive operations. A type of transformation, which is called extraction, plays a central role in the generation algorithm. 相似文献