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271.
Tran Duc Thiep Truong Thi An Nguyen Tuan Khai Nguyen The Vinh Phan Viet Cuong I. P. Gangrski I. E. Penhionzkevich G. V. Mishinski V. I. Zemenhik 《Journal of Radioanalytical and Nuclear Chemistry》2010,285(3):511-517
The ratio of the probabilities of population of the isomeric and ground states, so called the isomeric ratio is closely connected to the angular momentum of the initial fission fragments that is dissipated at the later stages of gamma ray cascade. This ratio also provides important information on the nuclear level structure as well as the nuclear reaction mechanism involved. In this work, the isomeric ratio in fission fragment 135Xe from photofission of 233U induced by 23.5 MeV bremsstrahlung has been determined by the method that uses inert gaseous flow. The results have been discussed and compared with that of other authors. 相似文献
272.
Tran Thi Viet NgaNguyen Phuc Duong Than Duc Hien 《Journal of magnetism and magnetic materials》2012,324(6):1141-1146
Ultrafine aluminum-substituted strontium hexaferrite particles have been prepared via citrate sol-gel route. Gels were synthesized with molar ratios [Al3+]:[Fe3+] of 0.4:11.6, 1:11, 1.5:10.5 and 2:10 and the ferrite particles were obtained by annealing the gels at 950 °C for 2 and 24 h. Electron energy dispersive X-ray spectroscopy (EDX) verified the presence of Al in the substituted samples. X-ray diffraction (XRD) confirmed the formation of the M-type hexaferrite phase in the samples with some indication of α-Fe2O3. Scanning electron microscope showed that the hexaferrite powder consists hexagonal crystals with average diameter Dav (80-186 nm) that decreases with increasing Al content and increases with increasing annealing time. Magnetic properties were determined using a pulsed-field magnetometer and a vibrating sample magnetometer (VSM). The saturation magnetization at room temperature and the Curie temperature were found to decrease while the coercivity increases with increasing the Al content. The highest coercivity of 10.1 kOe was achieved for the sample with the molar ratio [Al3+]:[Fe3+]=2:10 annealed for 24 h. The influences of the particle size, composition and impurity on the magnetic properties were discussed. 相似文献
273.
Angle Chiaroni Claude Riche Qui Khuong‐Huu Hanh Nguyen‐Ngoc Kinh Nguyen‐Viet Franoise Khuong‐Huu 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):711-713
Two minor compounds were isolated from a sample of Harrisonia perforata leaves collected in central Vietnam, namely haperforin B1, C27H32O9, and haperforin D, C27H34O10. Biogenetically, haperforin D and haperforin B1 can be derived from each other by addition or elimination of water. 相似文献
274.
Journal of Nanoparticle Research - Silicon nanocrystals (Si-NC) in silicon oxide is a promising material for many applications in micro- and nanoelectronics. This article develops a theory of the... 相似文献
275.
Nguyen Xuan Viet Nhan 《Mathematische Nachrichten》2023,296(7):2958-2974
It is known by a result of Mendes and Sampaio that the Lipschitz normal embedding of a subanalytic germ is fully characterized by the Lipschitz normal embedding of its link. In this note, we show that the result still holds for definable germs in any o-minimal structure on . We give an example showing that for homomorphisms between MD-homologies induced by the identity map, being isomorphic is not enough to ensure that the given germ is Lipschitz normally embedded. This is a negative answer to the question asked by Bobadilla et al. in their paper about moderately discontinuous homology. 相似文献