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131.
Dr. M. Tanaka Prof. Dr. M. Hamada Prof. Dr. Y. Iwata 《Archive of Applied Mechanics (Ingenieur Archiv)》1982,52(1-2):95-104
Summary This paper presents a boundary element formulation for elastostatic problems. The formulation is expressed in terms of the matrix notation, so that it is easily applicable to an available system of matrix structural analysis. A computer program developed is used to calculate the stress intensity factor K
I for some example problems in plane elasticity. Comparison is made between the boundary element calculations and other solutions, whereby the effectiveness of the boundary element method is demonstrated.
Berechnung eines zweidimensionalen Spannungsintensitätsfaktors mit der Methode der Bandelemente
Übersicht Dieser Aufsatz bietet eine Formulierung elastostatischer Probleme durch die Methode der Randelemente an. Die Formulierung benutzt eine Darstellung in Matrizenbezeichnung, so daß sie auf ein verfügbares System für Matrizenstrukturberechnung einfach anwendbar ist. Ein ausgebautes Computerprogramm wird auf die Berechnung des Spannungsintensitätsfaktors K i für einige Beispiele in der ebenen Elastizität angewendet. Die mittels der Randelemente erhaltenen Ergebnisse werden mit anderen Lösungen verglichen. Dadurch zeigt sich die Wirksamkeit der Methode der Randelemente.相似文献
132.
Ezzat Hany G. Bayoumi Ashraf H. Sherbiny Farag F. El-Morsy Ahmed M. Ghiaty Adel Alswah Mohamed Abulkhair Hamada S. 《Molecular diversity》2021,25(1):291-306
Molecular Diversity - Many shreds of evidence have recently correlated A2B receptor antagonism with anticancer activity. Hence, the search for an efficient A2B antagonist may help in the... 相似文献
133.
AbdElAziz A. Nayl Hamada Mohamed Ibrahim Kamal M. Dawood Wael A. A. Arafa Ahmed I. Abd-Elhamid Ismail M. Ahmed Mohamed A. Abdelgawad Hazim M. Ali Ibrahim Hotan Alsohaimi Ashraf A. Aly Stefan Brse Asmaa Kamal Mourad 《Molecules (Basel, Switzerland)》2022,27(19)
An appropriate and efficient Q-tube-assisted ammonium acetate-mediated protocol for the assembly of the hitherto unreported 5-arylazopyrazolo[3,4-b]pyridines was demonstrated. This methodology comprises the cyclocondensation reaction of 5-amino-2-phenyl-4H-pyrazol-3-one with an assortment of arylhydrazonals in an NH4OAc/AcOH buffer solution operating a Q-tube reactor. This versatile protocol exhibited several outstanding merits: easy work-up, mild conditions, scalability, broad substrate scope, safety (the Q-tube kit is simply for pressing and sealing), and a high atom economy. Consequently, performing such reactions under elevated pressures and utilizing the Q-tube reactor seemed preferable for achieving the required products in comparison to the conventional conditions. Diverse spectroscopic methods and X-ray single-crystal techniques were applied to confirm the proposed structure of the targeted compounds. 相似文献
134.
Hiroaki Koga Takeyuki Arai Taisuke Hamada Shigeyoshi Sakaki 《Journal of molecular catalysis. A, Chemical》2003,200(1-2):223-228
In the two-electron reduction of diphenylsulfoxide to diphenylsulfide, which is considered a model reaction of sulfite reduction catalyzed by sulfite reductase, methylviologen-pendent iron(III) porphyrin exhibits much higher catalytic activity than usual iron(III) and manganese(III) tetraphenylporphyrins, while cobalt(II) tetraphenylporphyrin exhibits much less catalytic activity than the others. Discussion about the active species and the reason of the acceleration by methylviologen-pendent is presented. 相似文献
135.
T. Ocho S. Kubo M. Ikeda T. Saito Y. Terumichi Y. Hamada S. Tanaka 《Physics letters. A》1980,77(5):318-320
When ohmic heating power is applied during the microwave discharge at the electron cyclotron resonance, the plasma current and density build-up become fast and the loop voltage required to start the tokamak discharge decreases. The micro-wave burst observed in the initial stage is reduced and the burst of hard X-rays, occurring at the quasi-steady stage of discharge in the case of no microwave injection, disappears, suggesting that the production of run-away electrons is suppressed strongly. 相似文献
136.
137.
Koji Ishida Tomoshige Morita Takeshi Hamada 《Fresenius' Journal of Analytical Chemistry》1981,305(4):257-261
Summary The thin-layer chromatographic behaviour of the noble metals on ECTEOLA-cellulose has been examined in HCl and aqueous chloride solutions of Li, Na, Mg, Ca, Sr and Al. The Rf-values decrease in the order Ir(III) Rh(III) > Ru(III) > Pd(II) > Pt(IV) > Ir(IV) > Au(III) in all of the media of higher chloride concentrations (3M to 5M), in which there are sufficiently large differences in Rf-values of adjacent metals to resolve them clearly. Especially, the HCl solutions with or without H2O2 are very suitable for multi-component separations of the noble metals.
DC-Trennung von Edelmetallen auf ECTEOLA-Cellulose in salzsauren und wäßrigen Chloridlösungen
Zusammenfassung Das Verhalten von Edelmetallen wurde in salzsauren Lösungen sowie in Lösungen der Chloride von Li, Na, Mg, Ca, Sr und Al geprüft. Die Rf-Werte nehmen in allen Medien mit höherer Chlorid-konzentration (3M bis 5M) in folgender Reihenfolge ab: Ir(III) Rh(III) > Ru(III) > Pd(II) > Pt(IV) > Ir(IV) > Au(III). Die Unterschiede in den Rf-Werten sind groß genug, um eine deutliche Trennung zu gewährleisten. Salzsaure Lösungen mit oder ohne H2O2-Zusatz sind besonders gut für die Trennung von Vielkomponenten-Gemischen geeignet.相似文献
138.
The problem of constructing a maximal t-linearly independent set in V(r; s) (called a maximal Lt(r, s)-set in this paper) is a very important one (called a packing problem) concerning a fractional factorial design and an error correcting code where V(r; s) is an r-dimensional vector space over a Galois field GF(s) and s is a prime or a prime power. But it is very difficult to solve it and attempts made by several research workers have been successful only in special cases.In this paper, we introduce the concept of a {Σα=1kwα, m; t, s}-min · hyper with weight (w1, w2,…, wk) and using this concept and the structure of a finite projective geometry PG(n ? 1, s), we shall give a geometrical method of constructing a maximal Lt(t + r, s)-set with length t + r + n for any integers r, n, and s such that n ? 3, n ? 1 ? r0 ? n + s ? 2 and r1 ? 1, where r = (r1 + 1)vn?1 ? r0 and . 相似文献
139.
Yoshiaki Amatatsu Yoshiaki Hamada Masamichi Tsuboi Masaaki Sugie 《Journal of Molecular Spectroscopy》1985,111(1):29-41
The infrared spectrum of N-methylvinylamine was observed for the first time in the gas phase by the pyrolysis of propyleneimine. The half-life of this molecule was about 40 sec under our experimental conditions, and the molecule isomerized immediately into its tautomer, N-methylethylideneimine. The absorption bands were assigned by the help of an ab initio MO calculation. 相似文献
140.
An ab initio Mo method was applied to analyse the vibrational spectra of amines and their pyrolytic products. The result was useful to predict the frequencies of group vibrations, and to explain the characteristics of molecular parameters. The relative populations of rotational conformers were calculated and the results were found to be in qualitative agreement with what were observed. 相似文献