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71.
Soo‐Na Ahn Hwa‐Jeong Lee Bang‐Jun Kim Loon‐Seng Tan Jong‐Beom Baek 《Journal of polymer science. Part A, Polymer chemistry》2008,46(22):7473-7482
Short length vapor‐grown carbon nanofibers (VGCNFs) were functionalized with 4‐aminobenzoic acid in polyphosphoric acid/phosphorous phentoxide medium via “direct” Friedel‐Crafts acylation reaction to afford aminobenzoyl‐functionalized VGCNFs (AF‐VGCNFs). The AF‐VGCNFs as a cocuring agent were mixed with epoxy resin by simple mechanical stirring in methanol which was added to help efficient mixing. After evaporation of methanol, 4,4′‐methylenedianiline as a curing agent was added to the mixture, which was then cured at elevated temperatures. The resultant composites displayed uniform dispersion of AF‐VGCNFs into cured epoxy matrix. During curing process, the amine functionalities on AF‐VGCNF together with 4,4′‐methylenedianiline were expected to be involved in covalent attachment to the epoxy resin. As a result, both tensile modulus and strength of the composites were improved when compared with those of pure epoxy resin. Thus, the AF‐VGCNFs play a role as an outstanding functional additive, which could resolve both dispersion and interfacial adhesion issues at the same time by functionalization of VGCNFs and covalent bonding between the additive and matrix, respectively. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7473–7482, 2008 相似文献
72.
73.
The total binding energy of nuclei is determined by means of many-body field theory. The problem is then reduced to finding the energy-dependent average potential (mass operator) and solving the single-particle equations of motion. Such a potential can be established phenomenologically by using data on low excitations and reactions knocking out nucleons from deep “hole” levels. Calculations of the total binding energy of the nuclei 16O, 40Ca and 58Ni with this potential are in satisfactory agreement with experiment. 相似文献
74.
Ha Huy Bang 《International Journal of Theoretical Physics》1996,35(4):747-753
Generalized deformed commutation relations for a single-mode para-Bose oscillator are constructed. The connection of generalized
deformed para-Bose oscillators with para-Bose oscillators is determined. From these, the energy spectrum of generalized deformed
para-Bose oscillators and the coherent states of the annihilation operators are discussed.
On leave from Department of Physics, Hanoi National University, 90 Nguyen Trai, Hanoi, Vietnam. 相似文献
75.
A tournament T on any set X is a dyadic relation such that for any x, y ∈ X (a) (x, x) ? T and (b) if x ≠ y then (x, y) ∈ T iff (y, x) ? T. The score vector of T is the cardinal valued function defined by R(x) = |{y ∈ X : (x, y) ∈ T}|. We present theorems for infinite tournaments analogous to Landau's necessary and sufficient conditions that a vector be the score vector for some finite tournament. Included also is a new proof of Landau's theorem based on a simple application of the “marriage” theorem. 相似文献
76.
J. M. Bang V. V. Flambaum J. M. Hansteen 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(4):431-432
Attention is drawn to a mechanism ofe + e ? pair production which may lead to peaks in the energy distribution of the pairs. 相似文献
77.
78.
Bang JK Naka H Teruya K Aimoto S Konno H Nosaka K Tatsumi T Akaji K 《The Journal of organic chemistry》2005,70(25):10596-10599
[reaction: see text] The solid-phase Horner-Emmons reaction was successfully applied for the convenient syntheses of olefin-containing protease inhibitors. The isomerization during the solid-phase Horner-Emmons reaction can be minimized simply by the use of an appropriate amount of the base. The synthesized olefin peptides, which have an olefin gamma-amino acid at the scissile site, were found to act as effective inhibitors for the HTLV-1 protease for the first time. 相似文献
79.
D.V. Aleksandrov Yu.A. Glukhov A.S. Demyanova A.A. Ogloblln S.B. Sakuta V.V. Sukharevsky S.V. Tolokonnikov S.A. Fayans F.A. Gareev S.N. Ershov I.N. Borzov J. Bang 《Nuclear Physics A》1985,436(2):338-364
The reaction 14C(6Li, 6He)14N was investigated with 93 MeV 6Li ions in an angular interval of 7–26°. Angular distributions were analysed for the four most intense groups of 6He nuclei, corresponding to transitions to the ground (11+) and the excited (12+, 21?, 41?) states of 14N. In the theoretical analysis a mechanism of the spin-isospin excitation was suggested in the DWBA frame with the finite range of interaction and recoil in the light system (6Li6He) taken into account. In the calculations both shell-model wave functions and transition densities obtained in the theory of finite Fermi systems (FFS) were used. From the comparison between theory and experiment the Landau-Migdal force constant g′ is estimated in order to obtain some information on the degree of nuclear proximity to the threshold of pion condensation. 相似文献
80.
The convergence of a Neumann-series solution of the Marchenko equation in L
2[x, ∞) is proved and an explicit expression of the series solution is given. 相似文献