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911.
Cross-sections of the(n,2n) reactions for neodymium(Nd) isotopes induced by 14 MeV neutrons were measured in this work by using the activation and relative methods. The measured cross-sections of the ~(150)Nd(n,2n)~(149)Nd,~(148)Nd(n,2n)~(147)Nd, and ~(142)Nd(n,2 n)~(141)Nd reactions were 1854 ± 81, 1789 ± 119, and 1559 ± 98 mb, respectively, at a neutron energy of 14.2 ± 0.2 MeV,and 1485 ± 74, 1726 ± 85, and 1670 ± 119 mb, respectively, at 14.9 ± 0.2 MeV. The results were compared with the experimental values from the reported literature, with the evaluated data from the ENDF/B-VII.1, CENDL-3.1, and JENDL-4.0 libraries, and with the curves calculated by the Talys-1.8 code. 相似文献
912.
The nuclear data of n+~(240;242;244)Pu reactions for incident energy below 200 MeV are calculated and evaluated to meet the requirement in the design of an accelerator-driven subcritical system. The optical model is used to calculate the total, nonelastic, shape elastic cross sections, shape elastic scattering angular distributions, and transmission coefficients. The distorted-wave Born approximation is applied to calculate the direct inelastic scatterings to the discrete excited states. The nuclear reaction statistical models and fission theory are applied to describe neutron, proton, deuteron, triton, helium-3, alpha and c emissions, and fission consistently. The results thus obtained are compared with experimental data and the evaluated data obtained from ENDF/B-VII.1 and JENDL-4.0. 相似文献
913.
The thorium molten salt reactor–liquid fuel(TMSR-LF1) has inherent safety features. The accident occurrence possibility and their consequences are much lower for the TMSR-LF1 than that of traditional reactors.Based on accident analysis, the maximum credible accident and the radioactive source terms of the TMSR-LF1 were first estimated. Then, the total effective dose of the maximum credible accident was calculated. Based on calculations, the cover gas flow rate can significantly affect the radiation consequences of the maximum credible accident when it changes from 0 to 10 L/min. If no cover gas is flowing, a site-area emergency would be required within the range of 50–73 m from the reactor. In the case of cover gas flow, only an abnormal notification and an alert two emergency class would be required within the range of 50 m. 相似文献
914.
A series of inorganic yellow pigments with general formula Y_(4-x)A_xMoO_(9+δ)(A = Ta, Tb), where x = 0,0.05,0.1,0.2, 0.4 for Ta and χ = 0, 0.005, 0.01.0.03, 0.05 for Tb,were synthesized by a conventional ceramic method at 1400 ℃ for 6 h in air. The samples were characterized by XRD,EDS,XPS,SEM,TG-DSC,UV-vis-NIR reflectance spectroscopy and CIE L*a*b* color scales. It is found that the substitution of A(A = Ta, Tb) for Y~(3+) in Y_4 MoO_9 decreases the NIR reflectance of the pigment samples, but the developed pigments Y_(4-x)A_xMoO_(9+δ)(A = Ta, Tb) still exhibit impressive NIR solar reflectance. The brighter yellow color of inorganic pigments Y_(4-x)A_xMoO_(9+δ)(A = Ta, Tb) is available when x is about 0.1 for Ta and 0.01 for Tb. The results make them a series of potential candidates as ecological yellow pigments because of their high reflectance, lightness, intense coloration and excellent thermal and chemical stability. 相似文献
915.
Yang Jian Wang Qi Zhang Jianqiang Ostrovski Oleg Zhang Chen Cai Dexiang 《Metallurgical and Materials Transactions B》2019,50(6):2794-2803
Metallurgical and Materials Transactions B - CaO-Al2O3-based mold fluxes, which are under development for the continuous casting of high-Al steel, contain fluxing compounds, such as Na2O and B2O3.... 相似文献
916.
917.
空预器作为我国大型火力发电厂重要组成部分,其高效、稳定的运行对于火电机组而言具有十分重大的意义.当前,我国大部分火电机组均存在空预器堵塞现象,严重影响到锅炉安全、经济运行,为此,本文基于宝庆发电公司660MW机组三分仓容克氏空预器吹灰改造展开研究,对变工况下空预器吹灰改造前后差压变化做出对比分析,以及对定工况下空预器烟... 相似文献
918.
Qing-Chao Li Bo Wang Yan-Hua Zeng Zhong-Hua Cai Jin Zhou 《International journal of molecular sciences》2022,23(7)
Marine biofouling is a worldwide problem in coastal areas and affects the maritime industry primarily by attachment of fouling organisms to solid immersed surfaces. Biofilm formation by microbes is the main cause of biofouling. Currently, application of antibacterial materials is an important strategy for preventing bacterial colonization and biofilm formation. A natural three-dimensional carbon skeleton material, TRP (treated rape pollen), attracted our attention owing to its visible-light-driven photocatalytic disinfection property. Based on this, we hypothesized that TRP, which is eco-friendly, would show antifouling performance and could be used for marine antifouling. We then assessed its physiochemical characteristics, oxidant potential, and antifouling ability. The results showed that TRP had excellent photosensitivity and oxidant ability, as well as strong anti-bacterial colonization capability under light-driven conditions. Confocal laser scanning microscopy showed that TRP could disperse pre-established biofilms on stainless steel surfaces in natural seawater. The biodiversity and taxonomic composition of biofilms were significantly altered by TRP (p < 0.05). Moreover, metagenomics analysis showed that functional classes involved in the antioxidant system, environmental stress, glucose–lipid metabolism, and membrane-associated functions were changed after TRP exposure. Co-occurrence model analysis further revealed that TRP markedly increased the complexity of the biofilm microbial network under light irradiation. Taken together, these results demonstrate that TRP with light irradiation can inhibit bacterial colonization and prevent initial biofilm formation. Thus, TRP is a potential nature-based green material for marine antifouling. 相似文献
919.
Fear memory helps animals and humans avoid harm from certain stimuli and coordinate adaptive behavior. However, excessive consolidation of fear memory, caused by the dysfunction of cellular mechanisms and neural circuits in the brain, is responsible for post-traumatic stress disorder and anxiety-related disorders. Dysregulation of specific brain regions and neural circuits, particularly the hippocampus, amygdala, and medial prefrontal cortex, have been demonstrated in patients with these disorders. These regions are involved in learning, memory, consolidation, and extinction. These are also the brain regions where new neurons are generated and are crucial for memory formation and integration. Therefore, these three brain regions and neural circuits have contributed greatly to studies on neural plasticity and structural remodeling in patients with psychiatric disorders. In this review, we provide an understanding of fear memory and its underlying cellular mechanisms and describe how neural circuits are involved in fear memory. Additionally, we discuss therapeutic interventions for these disorders based on their proneurogenic efficacy and the neural circuits involved in fear memory. 相似文献
920.