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排序方式: 共有338条查询结果,搜索用时 625 毫秒
91.
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93.
B. N. Gikal S. N. Dmitriev G. G. Gul’bekyan P. Yu. Apel’ V. V. Bashevoi S. L. Bogomolov O. N. Borisov V. A. Buzmakov I. A. Ivanenko O. M. Ivanov N. Yu. Kazarinov I. V. Kolesov V. I. Mironov A. I. Papash S. V. Pashchenko V. A. Skuratov A. V. Tikhomirov M. V. Khabarov A. P. Cherevatenko N. Yu. Yazvitskii 《Physics of Particles and Nuclei Letters》2008,5(1):33-48
Industrial production of nuclear filters has been implemented at the IC-100 cyclotron complex of the Laboratory of Nuclear Reactions at the Joint Institute for Nuclear Research. After the complete upgrade, the cyclotron was equipped with the superconducting ECR ion source and the system of external axial beam injection. The implantation complex was equipped with the special transportation channel with the beam scanning system and the setup for irradiation of polymer films. Intense beams of heavy ions Ne, Ar, Fe, Kr, Xe, I, and W with an energy of ~1 MeV/nucleon were obtained. the properties of irradiated crystals were studied, different polymer films were irradiated, and several thousands of square meters of track membranes with pore densities varying in a wide range were produced. Other scientific and applied problems can be solved at the cyclotron complex. 相似文献
94.
We report true left-handed (LH) behavior in a composite metamaterial consisting of a periodically arranged split ring resonator (SRR) and wire structures. We demonstrate the magnetic resonance of the SRR structure by comparing the transmission spectra of SRRs with those of closed SRRs. We have confirmed experimentally that the effective plasma frequency of the LH material composed of SRRs and wires is lower than the plasma frequency of the wires. A well-defined LH transmission band with a peak value of -1.2 dB (-0.3 dB/cm) was obtained. The experimental results agree extremely well with the theoretical calculations. 相似文献
95.
We present a class of exact ground states of a three-dimensional periodic Anderson model at 3/4 filling. Hopping and hybridization of d and f electrons extend over the unit cell of a general Bravais lattice. Employing novel composite operators combined with 55 matching conditions the Hamiltonian is cast into positive semidefinite form. A product wave function in position space allows one to identify stability regions of an insulating and a conducting ground state. The metallic phase is a non-Fermi liquid with one dispersing and one flat band. 相似文献
96.
Manzur-ul-Haque Hashmi Gul Akhtar Minhas Mohammad Iqbal Durrani Riaz-ur-Rehman 《Mikrochimica acta》1969,57(2):286-289
Summary A method for the preparation of ore solutions by grinding the ore with distilled water is developed for the analysis of minerals and ores in the field by the circular thin-layer Chromatographic technique.
Zusammenfassung Die Herstellung von Erzlösungen durch Mahlen des Erzes mit dest. Wasser zur Feldanalyse von Mineralen und Erzen durch Ring-Dünnschichtchromatographie wird empfohlen.相似文献
97.
V. E. Gul 《Mechanics of Composite Materials》1968,4(3):380-385
The results of an experimental verification of the activation concept of strength, first proposed by the author in 1952, are described. The theoretical conclusions are confirmed by tests on various vulcanizates, polystyrene, polymethyl methacrylate, cellophane, and polypropylene, New means of improving the strength of polymers are suggested.Mekhanika Polimerov, Vol. 4, No. 3, pp. 474–482, 1968 相似文献
98.
The effect of bond strength on over-all tensile strength has been investigated in relation to two-layer materials consisting of cellophane film cut in the longitudinal and transverse directions and bonded with polyisobutylene. It is shown that there is a linear correlation between the bond strength and the combination hardening effect. The breaking stress of two-layer materials is higher than that of the individual films. A possible explanation of this effect is proposed.Mekhanika Polimerov, Vol. 3, No. 1, pp. 89–94, 1967 相似文献
99.
Recep Özen Kutalmis Guven Hatice Can Metin Balci 《Journal of chemical crystallography》2004,34(7):477-481
The title compound 6-phenyl-4,6,8-triazatetracyclo[9.2.1.02,10.04,8]tetradec-2(10)-ene-5,7-dione (6) has been synthesized by the addition of 4-phenyl-1,2,4-triazole-3,5-dione (PTAD) to 2,3-dimethylenebicyclo[2.2.1]heptane. The cell parameters are a = 9.991(5), b = 11.754(9), c = 6.549(5) Å, = 101.08(7)°, = 103.31(5)°, = 98.24(5)°. The crystal structure of 6 was determined. The obtained geometrical parameters were highly correlated with the DFT calculations. The experimentally determined folding angle of the double bond was found to be 8.44°. The effect of the electron-withdrawing ability of nitrogen atom on the degree of pyramidalization is discussed. 相似文献
100.