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101.
Cross-section measurements of (n, 2n) and (n, p) reactions on 124,126,128,130,131,132Xe in the 14 MeV region and theoretical calculations of their excitation functions
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Junhua Luo Li Jiang Juncheng Liang Fei Tuo Long He Liang Zhou 《中国物理C(英文版)》2022,46(4):044001-044001-13
The reaction cross-sections of 124Xe(n, 2n)123Xe, 126Xe(n, 2n)125Xe, 128Xe(n, 2n)127Xe, 130Xe(n, 2n)129mXe, 132Xe(n, 2n)131mXe, 130Xe(n, p)130I, 131Xe(n, p)131I, and 132Xe(n, p)132I were measured at the 13.5, 13.8, 14.1, 14.4, and 14.8 MeV neutron energies. The monoenergetic neutrons were generated via the 3H(d,n)4He reaction at the China Academy of Engineering Physics using the K-400 Neutron Generator with a solid 3H-Ti target. A high-purity germanium detector was employed to measure the activities of the product. The reactions 93Nb(n, 2n)92mNb and 27Al(n, α)24Na were adopted for neutron flux calibration. The cross sections of the (n, 2n) and (n, p) reactions of the xenon isotopes were obtained within the 13–15 MeV neutron energy range. These cross-sections were then compared with the IAEA-exchange format (EXFOR) database-derived experimental data, together with the evaluation results of the CENDL-3, ENDF/B-VIII.0, JENDL-4.0, RUSFOND, and JEFF-3.3 data libraries, as well as the theoretical excitation function obtained using the TALYS-1.95 code. The cross-sections of the reactions (except for the 124Xe(n, 2n)123Xe and 132Xe(n, p)132I) at 13.5, 13.8, and 14.1 MeV are reported for the first time in this study. The obtained results are beneficial in providing better cross-section constraints for the reactions in the 13–15 MeV region, thus improving the quality of the corresponding database. Meanwhile, these data can also be used for the verification of relevant nuclear reaction model parameters. 相似文献
102.
自五十年代首次实现光抽运技术以来,人们用它已对多种原子进行了极化原子束制备的研究[1~5],但所有这些工作只是以相对简单的碱金属原子为对象,而对价电子数大于1的复杂原子的极化原子束的制备目前尚未见报道.描述了用一台连续波染料激光器对复杂原子Eu进行了弱场制备极化原子束的实验研究,得到了较满意的结果. 相似文献
103.
104.
We report a quantitative comparison of measured intensities of neutron powder diffraction data collected in a single-crystal diamond anvil cell and in large-volume sintered diamond anvils. As expected from the difference in sample volumes, the latter provides 1–2 orders of magnitude higher intensities, depending on the anvil material. The remaining differences are due to effects of absorption and angular aperture. 相似文献
105.
I. Kh. Abdukadyrova 《Journal of Applied Spectroscopy》2003,70(6):890-895
The characteristic features of the process of radiation-defect formation and of a change in the structural and optical properties of corundum crystals exposed to reactor radiation have been investigated by spectroscopic methods. The dose dependences of the generation of a number of color and luminescence centers, the regularities of their thermal and photodecoloration, and the energies of activation of the centers have been determined. The influence of the overlapping of the absorption and luminescence centers has been estimated. The radiation-induced change in the structural parameters of the crystal and in the characteristics of the main reflexes has been determined. It has been established that at large reactor radiation fluxes the processes of damage of the crystal are accelerated and a small halo appears at 12.5°. The possible mechanism of damage and disordering of the structure of corundum irradiated in the reactor with a fairly large flux is discussed. 相似文献
106.
Recently it has been proposed to use the 14-MeV neutrons produced in the muon-catalyzed dt fusion reaction for the thermonuclear reactors first wall materials testing. The results of the Monte Carlo computations of some of the most interesting conceptual schemes of such a source are presented. It was shown that a neutron flux of about 1014 n/cm2 s, can be achieved in the case of a scheme based on a mirror trap with strong magnetic fields, as proposed in this work. 相似文献
107.
Ole Buchardt 《Angewandte Chemie (International ed. in English)》1974,13(3):179-185
The reactions induced by circularly polarized light are reviewed and a general discussion of the induction of optical activity by circularly polarized light is presented. It is concluded that three different mechanisms, or their combinations, can cause asymmetric induction. In each case the optical yield is dependent on the optical anisotropy factor g, the ratio between the circular dichroism (Δ?) and the extinction coefficient (?). The results are discussed in terms of the presumed mechanisms, and particular attention is paid to the asymmetric synthesis of helicenes. It is concluded that this kind of photochemistry may have analytical importance. 相似文献
108.
P. S. Goyal 《Phase Transitions》2013,86(1-3):143-176
Small angle neutron scattering (SANS) is an ideal tool for studying structures of macromolecules and colloidal solutions. A number of micellar solutions have been studied in our laboratory using a home built SANS spectrometer. This paper gives an introduction to the technique of SANS and gives a brief survey of the results obtained at Trombay. 相似文献
109.
The new TOFLAR-method enables quasi-elastic and inelastic measurements in the picosecond to nanosecond regime. In this paper the principal idea of the technique is discussed and the results of some first measurements on the dynamics of acetone and water are shown. 相似文献
110.
Geminiano Martínez-Ponce Cristina SolanoCarlos Pérez-Barrios 《Optics and Lasers in Engineering》2011,49(6):723-728
Optical properties of matter as diattenuation, retardance and depolarization can be evaluated using polarimetric techniques. In this paper, the analysis and implementation of a complete Mueller polarimeter is presented. The system is constituted of a polarization state generator (PSG) and a polarization state analyzer (PSA), which are controlled and synchronized through a computer program. The PSG comprises a dual liquid crystal variable retarder system while the PSA is based on a two-photoelastic modulator setup. Using air and common polarizing optics as test samples for calibration at 633 nm, the hybrid instrument met a good precision when the Mueller matrices of those optical elements were measured. 相似文献