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排序方式: 共有380条查询结果,搜索用时 15 毫秒
91.
We investigate effects of oxygen vacancies on adhesion behavior of incoherent Ni/MgO(0 0 1) interface with large misfit, based on the density functional theory. We demonstrate that oxygen vacancies at any local atomic configuration of the incoherent geometry enhance the image-chargelike interaction between the ions in MgO and the ion-induced images in Ni, and stabilize adhesion of the Ni/MgO(0 0 1) interface. The adhesion energy of the defective interface is remarkably larger than that of the perfect interface. We also show that force constants of the adhesive interactions near the oxygen vacancies are comparable to the Ni-Mg bond at the perfect interface. The vacancy-induced enhancement of the image electron accumulation hardly contributes to the interfacial stiffness, while it is reduced by losing the covalent Ni-O interaction due to an ontop oxygen vacancy. 相似文献
92.
Jespersgaard C Larsen LA Baba S Kukita Y Tahira T Christiansen M Vuust J Hayashi K Andersen PS 《Electrophoresis》2006,27(19):3816-3822
Mutation screening is widely used for molecular diagnostics of inherited disorders. Furthermore, it is anticipated that the present and future identification of genetic risk factors for complex disorders will increase the need for high-throughput mutation screening technologies. Capillary array electrophoresis (CAE) SSCP analysis is a low-cost, automated method with a high throughput and high reproducibility. Thus, the method fulfills many of the demands to be met for application in routine molecular diagnostics. However, the need for performing the electrophoresis at three temperatures between 18 degrees C and 35 degrees C for achievement of high sensitivity is a disadvantage of the method. Using a panel of 185 mutant samples, we have analyzed the effect of sample purification, sample medium and separation matrix on the sensitivity of CAE-SSCP analysis to optimize the method for molecular diagnostic use. We observed different effects from sample purification and sample medium at different electrophoresis temperatures, probably reflecting the complex interplay between sequence composition, electrophoresis conditions and sensitivity in SSCP analysis. The effect on assay sensitivity from three different polymers was tested using a single electrophoresis temperature of 27 degrees C. The data suggest that a sensitivity of 98-99% can be obtained using a 10% long chain poly-N,N-dimethylacrylamide polymer. 相似文献
93.
Akutsu M Koyasu K Atobe J Hosoya N Miyajima K Mitsui M Nakajima A 《The journal of physical chemistry. A》2006,110(44):12073-12076
The geometric and electronic structures of aluminum binary clusters, AlnX (X = Si and P), have been investigated, using mass spectrometry, anion photoelectron spectroscopy, photoionization spectroscopy, and theoretical calculations. Both experimental and theoretical results show that Al12Si has a high ionization energy and low electron affinity and Al12P has a low ionization energy, both with the icosahedral structure having a central Si or P atom, revealing that Al12Si and Al12P exhibit rare-gas-like and alkali superatoms, respectively. Experiments confirmed the possibility that the change in the total number of valence electrons on substitution could produce ionically bound binary superatom complexes, the binary cluster salts Al12P+ F- and Al12B- Cs+. 相似文献
94.
Shinya Miyajima 《Journal of Computational and Applied Mathematics》2010,234(12):3436-3444
Fast algorithms for enclosing minimal 2-norm solutions in underdetermined systems are proposed. For developing these algorithms, theory for computing error bounds for numerical solutions is established. Moreover techniques for accelerating the enclosure and obtaining smaller error bounds are introduced. Numerical results show the properties of the proposed algorithms. 相似文献
95.
Jordan and alternative tori are the coordinate algebras of extended affine Lie algebras of types and . In this paper we show that the derivation algebra of a Jordan torus is a semidirect product of the ideal of inner derivations and the subalgebra of central derivations. In the course of proving this result, we investigate derivations of the more general class of division graded Jordan and alternative algebras. We also describe invariant forms of these algebras.
96.
Seiji Yamaguchi Mika Yoshida Izumi Miyajima Toshikatsu Araki Yoshiro Hirai 《Journal of heterocyclic chemistry》1995,32(5):1517-1519
Condensation of salicylonitrile with ethyl α-bromo-α-(o-ethoxycarbonylphenyl)acetate (4) effectively gave 5 (6H)-benzofuro[3,2-c]isoquinolinone (2) , which was converted to some 5-substituted benzofuro-[3,2-c]isoquinoline derivatives 1a-g. 相似文献
97.
98.
Stefan Machill Takahisa Shodai Yoji Sakurai Jun-ichi Yamaki 《Journal of Solid State Electrochemistry》1999,3(2):97-103
Tin-based composite oxide materials have received considerable attention as potential anode materials for rechargeable lithium
batteries. In this contribution we present the results of our investigations of the SnOB2O3P2O5 system. We have investigated its electrochemical properties and especially its cycling performance. A focus of our interest
was to explain the structural changes which occur during lithium cycling and their strong dependence on the preparation method.
A part of the SnO component was converted into a very stable metallic phase. In addition, a decrease was observed in capacity
owing to the formation of isolated and inactive tin grains. We also report on structural changes in the B2O3P2O5 matrix.
Received: 2 October 1997 / Accepted: 3 July 1998 相似文献
99.
V. A. Kul’bachinskii A. Yu. Kaminskii N. Miyajima M. Sasaki H. Negishi M. Inoue H. Kadomatsu 《JETP Letters》1999,70(11):767-771
The quantization of the Hall resistivity ρxy in the form of plateaus in the dependence of ρxy on the magnetic field B is observed in the semiconductors Bi2Te3 and Sb2Te3; the minima of the transverse magnetoresistivity ρxx correspond to the start of the plateaus. The quantization of ρxy is due to the presence of a current-carrier reservoir. An impurity band with a high density of states or a different band
with a much higher current-carrier effective mass serves as the reservoir.
Pis’ma Zh. éksp. Teor. Fiz. 70, No. 11, 754–758 (10 December 1999) 相似文献
100.
Osamu Tanaike Hitoshi Kawabuchi Hiroaki Hatori Ryohei Asakura Naoya Miyajima Yoshio Yamada 《Journal of Non》2009,355(48-49):2405-2409
Two types of perfluorocarbon compounds, aliphatic perfluorooctane and aromatic octafluorotoluene, were co-defluorinated using sodium metal, and amorphous carbons were deposited from the vapor phase at very low temperature, 423 K. The products showed morphologies composed of fibrous, platelet, and spherical forms, which were dependent on the mixing ratio of the two. The BET surface areas also correlated well with the ratio of the starting mixtures, indicating that the surface area could be adjusted by changing the mixing ratio of these two compounds. However, when the carbonaceous product was further annealed in situ at 573 or 673 K, the porosities also modified. First the porosity decreased at 573 K, then increased greatly at 673 K, where radical interaction to shrink the pores and crystal growth of template fluoride occurred at 573 K and 673 K, respectively. 相似文献