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141.
The ambitious nuclear power program motivates the Chinese nuclear community to develop advanced reactor concepts of generation IV, in order to ensure the longterm, stable and sustainable development of nuclear power. The supercritical watercooled reactor (SCWR) has favorable features in economics, sustainability and technology availability. It is the logical extension of the existing PWR technology and has very promising perspectives in largescale power generation in China. This paper describes the main features of SCWR. New designs of SCWR core structure and fuel assemblies are proposed. Preliminary analysis using a coupled neutronphysics/thermalhydraulics method is carried out and shows a good feasibility of the new design proposal. 相似文献
142.
Camille Flament Joël Ribis Jérôme Garnier Thierry Vandenberghe Jean Henry Alexis Deschamps 《哲学杂志》2015,95(8):906-917
The age hardening 6061-T6 aluminium alloy has been chosen as structural material for the core vessel of the material testing Jules Horowitz nuclear reactor. The alloy contains incoherent Al(Cr, Fe, Mn)Si dispersoids whose characterization by energy-filtered transmission electron microscopy (EFTEM) analysis shows a core/shell organization tendency where the core is (Mn, Fe) rich, and the shell is Cr rich. The present work studies the stability of this organization under irradiation. TEM characterization on the same particles, before and after 1 MeV electron irradiation, reveals that the core/shell organization is enhanced after irradiation. It is proposed that the high level of point defects, created by irradiation, ensures a radiation-enhanced diffusion process favourable to the unmixing forces between (Fe, Mn) and Cr. Shell formation may result in the low-energy interface segregation of Cr atoms within the (Fe, Mn) system combined with the unmixing of Cr, Fe and Mn components. 相似文献
143.
《Current Applied Physics》2015,15(9):1036-1041
Spatial distributions of the effective electron temperature (Teff) and plasma potential were studied from the measurement of an electron energy probability function in a side type ferrite-core inductively coupled plasma with an argon–helium mixture. As the helium gas was diluted at the fixed total gas pressure of 5 mTorr in an argon discharge, the distribution of the plasma density and plasma potential changed from a concave to a flat profile, and finally became a convex profile, while all spatial profiles of Teff were hollow shapes with helium dilution in the argon discharge. This evolution of the plasma potential with helium gas could be explained by the increased energy relaxation length (λε), indicating the transition of electron kinetics from local to non-local kinetics. 相似文献
144.
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146.
Fei Lv Jianfeng Fan Jiarong Huang Liming Cao Xuesong Yan Ling Ge Saifudin Abubakar Yukun Chen 《先进技术聚合物》2020,31(10):2161-2171
As the most successful commercialized thermoplastic vulcanizates (TPVs), polypropylene (PP)/ethylene propylene rubber (EPDM) TPVs exhibit poor oil resistance. In this work, we prepared PP/EPDM/butadiene acrylonitrile rubber (NBR) ternary TPVs with good oil resistance using core‐shell dynamic vulcanization. According to the theoretical analysis of the spreading coefficient and the transmission electron microscopy results, the rubber phases exhibited a special core‐shell structure, in which the cross‐linkedNBR‐core was encapsulated by the EPDM‐shell. The core‐shell structure effectively improved the interfacial compatibility between PP and NBR phase as the EPDM‐shell could avoid the direct contact of them, thus improving the mechanical properties of the TPVs. For example, the PP/EPDM/NBR (40/30/30) ternary TPV showed enhanced tensile strength of 12.57 MPa, compared with 10.71 MPa of PP/EPDM (40/60) TPV and 11.11 MPa of PP/NBR (40/60) TPV, respectively. Moreover, the oil resistance of the TPVs was also improved. Compared with PP/EPDM TPV, the change rates in mass, volume, tensile strength and elongation at break of PP/EPDM/NBR TPV after oil immersion decreased by 42.18%, 48.69%, 52.68% and 28.77%, respectively. 相似文献
147.
Starch nanoparticle (SNP)‐based pressure sensitive adhesives (PSAs) with core‐shell particle morphology (starch nanoparticle core/acrylic polymer shell) are produced via seeded, semi‐batch emulsion polymerization at 15 wt% SNP loading (relative to total polymer weight) and 40 wt% latex solids. Crosslinker and chain transfer agent (CTA) are introduced to the acrylic shell polymer formulation at a range of concentrations according to a 32 factorial design to tailor the latex and adhesive properties of SNP‐based latexes. The crosslinker and CTA show no significant effect on polymerization kinetics, particle size, and viscosity. Latex gel content is predicted using an empirical model, which is a function of crosslinker and CTA concentration. Both the gel content and glass transition temperature strongly affect the adhesive properties (tack, peel strength, and shear strength) of the SNP‐based latex films. 3D response surfaces for the adhesive properties are constructed to facilitate the design of SNP‐based PSAs with desired properties. 相似文献
148.
高新技术企业核心能力体系研究 总被引:1,自引:0,他引:1
从高新技术企业竞争力的形成层次为研究视角,在比较研究了不同学派对企业核心竞争能力的理解和偏差基础上,立足产业组织理论角度从企业绩效决定因素来建立企业的行为———结构———绩效模型,从而分析高新技术企业的核心竞争力体系。 相似文献
149.
浅谈高校图书馆管理工作中的人本核心因素 总被引:2,自引:1,他引:1
李满秀 《科技情报开发与经济》2006,16(12):16-17
指出图书馆管理工作的核心必须以人为本,图书馆一切管理工作都应围绕人展开,图书馆的管理实质是人的管理,包括对图书馆职工的管理和对图书馆读者的管理。 相似文献
150.
论如何应用信息技术提升企业核心竞争力 总被引:4,自引:0,他引:4
董西梅 《科技情报开发与经济》2006,16(6):77-78
论述了信息技术在企业中的运用及对企业竞争力的影响,给出了利用信息技术提升企业核心竞争力的设想。 相似文献