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氦对LaNi5晶体结构的影响及其扩散特性研究

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物理学报 2008年第7期57卷 4379-4385页

作者：张传瑜高涛张云光周晶晶朱正和陈波四川大学原子与分子物理研究所中国工程物理研究院核物理与化学研究所绵阳621900

从密度泛函理论为基础的第一性原理出发,运用全势能线性缀加平面波(FLAPW)方法,对氚衰变后氦在合金中的占位以及LaNi5He晶体结构进行了理论计算,并系统给出了氦在间隙间的迁移曲线.结果表明,氦原子在十二面体(1b)格位最稳定,并且氦从6m... 详细信息

从密度泛函理论为基础的第一性原理出发,运用全势能线性缀加平面波(FLAPW)方法,对氚衰变后氦在合金中的占位以及LaNi5He晶体结构进行了理论计算,并系统给出了氦在间隙间的迁移曲线.结果表明,氦原子在十二面体(1b)格位最稳定,并且氦从6m格位向1b格位迁移不存在势垒,而从2d格位向1b格位迁移则需越过1.55eV高的势垒.另外,氦从12n格位穿过12o格位最后到达6m格位也无明显势垒存在,并且处于4h格位之间的氦原子可以自由迁移,而相应12n格位之间的直接迁移则需跨越13.6eV高的势垒.最后还计算给出了氚衰变后合金的态密度、电子密度以及势能分布图,并与相应的LaNi5H结构作了详细比较.

关键词：全势能线性缀加平面波(FLAPW) LaNi5He 态密度扩散

Trace tritium recovery from the residue of liquid Li_(17)Pb_(83) alloy

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Science china chemistry 2010年第8期53卷 1825-1828页

作者： XIE Bo,YANG TongZai & WENG KuiPing institute of nuclear physics and chemistry,china academy of engineering physics,mianyang 621900,china institute of nuclear physics and chemistry China Academy of Engineering Physics Mianyang China

The liquid Li17Pb83 alloy is a prominent breeder material for use in a fusion *** the design of an effective tritium extraction system for the liquid lithium lead bubbler of the test blanket module of such a reactor,finding ways to strictly limit the losses of tritium and to minimize radioactive risks is very *** this purpose,the isotope exchange process has been investigated as a means of trace tritium recovery from a model of the residue from Li17Pb83 *** results indicate that the isotope exchange process is an effective means of tritium recovery from the residue of Li17Pb83 alloy,and the optimum composition of the exchange carrier gas is He + 0.1% *** exchange temperature and number of exchange steps are the main factors influencing the efficiency of tritium recovery from the *** tritium recovery efficiency increases with increasing exchange temperature and number of times of *** recovery efficiency can approach 80% when the residue is treated six times at 823 K.A gas-liquid two-phase contact model to describe the proceeding of tritium release from the liquid Li17Pb83 alloy has been derived on the basis of this experiment.

关键词： Li17Pb83 alloy tritium recovery isotope exchange carrier

^(188)Re-HEDTMP在羟基磷灰石上的吸附效应

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同位素 2002年第4期15卷 207-209页

作者：邴文增罗顺忠蒋树斌杨玉青姜林何佳恒中国工程物理研究院核物理与化学研究所四川绵阳621900

在制备188Re-HEDTMP的基础上,研究了吸附时间、反应温度、配体羟乙基乙二胺三亚甲基膦酸(HEDTMP)用量、pH等因素对配合物在羟基磷灰石(HA)上吸附的影响。结果表明,吸附时间t=10min,n(HEDTMP)∶n(Re)=50∶1,pH=1.5时,可以得到最佳吸附结... 详细信息

在制备188Re-HEDTMP的基础上,研究了吸附时间、反应温度、配体羟乙基乙二胺三亚甲基膦酸(HEDTMP)用量、pH等因素对配合物在羟基磷灰石(HA)上吸附的影响。结果表明,吸附时间t=10min,n(HEDTMP)∶n(Re)=50∶1,pH=1.5时,可以得到最佳吸附结果,温度对吸附几乎没有影响;吸附产物体外稳定性较好。

关键词： ^188Re-HEDTMP 吸附效应羟基磷灰石铼188 放射性核素标记羟乙基二胺三亚甲基膦酸

Large-eddy simulations of the Richtmyer-Meshkov instability of rectangular interfaces accelerated by shock waves

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Science china(physics,Mechanics & Astronomy) 2010年第12期53卷 905-914页

作者： WANG Tao,BAI JingSong,LI Ping & LIU Kun institute of Fluid physics,china academy of engineering physics,mianyang 621900,china institute of Fluid physics China Academy of Engineering Physics Mianyang China

A parallel algorithm and code MVFT(multi-viscous-fluid and turbulence) of large-eddy simulation(LES) is developed from our MVPPM(multi-viscous-fluid piecewise parabolic method),and performed to solve the multi compressible Navier-Stokes(N-S) *** effect of the unresolved subgrid-scale(SGS) motions on the large scales is represented by different SGS stress models in LES.A Richtmyer-Meshkov instability experiment of the evolution of a rectangular block of SF6,which occupies half of the height of the shock tube test section,following the interaction with a planar shock wave,is numerically and exhaustively simulated by this *** comparison between experimental and simulated images of the evolving SF6 block shows that they are *** numerical simulations reproduce the complex developing process of SF6 block,which grows *** geometric quantities that characterize the extents of SF6 block are also compared in detail between numerical simulations and experiment with good agreements between them,a quantitative demonstration of the developing law of SF6 *** is an evident discrepancy between the three numerical simulations for the maximum position of the right edge of block at the late stage,because the right interface grows complicated and the dissipation is different for different SGS *** SGS turbulent dissipation,molecular viscosity dissipation and SGS turbulent kinetic energy have been studied and *** have a similar distribution to the large eddy *** SGS turbulent dissipation is much greater than the molecular viscosity dissipation;the SGS turbulent dissipation of Vreman model is smaller than the Smagorinsky *** general,the simulated results of Vreman SGS model are better compared with the dynamic viscosity and Smagorinsky SGS *** vorticity and circulation deposition on the block interface have also been investigated.

关键词： large-eddy simulation Navier-Stokes equations subgrid-scale Richtmyer-Meshkov instability turbulent dissipation turbulent kinetic energy circulation deposition

Ab initio Calculation of Intermolecular Dispersion Energy and Induction Energy of Nitramide Dimer

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chinese Journal of chemistry 2004年第11期22卷 1377-1381页

作者：宋华杰肖鹤鸣董海山institute of Chemical Materials china academy of engineering physics mianyang Sichuan 621900 china 黄奕刚institute of Chemical Materials china academy of engineering physics mianyang Sichuan 621900 china 龙新平institute of Chemical Materials china academy of engineering physics mianyang Sichuan 621900 china 汤业鹏institute of Chemical Materials china academy of engineering physics mianyang Sichuan 621900 china Department of chemistry Nanjing University of Science and Technology Nanjing Jiangsu 210094 China institute of Chemical Materials China Academy of Engineering Physics Mianyang Sichuan 621900 China

The dispersion energies, induction energies and their exchange counterparts (exchange-dispersion and ex-change-induction energies) between two interacting nitramide molecules at several separations are derived based upon symmetry-adapted perturbation theory (SAPT). The results show that (1) the effect of intramonomer electron correlation on dispersion energies and induction energies for nitramide dimer system is remarkable especially in the region near the van der Waals minimum distance (0.42 nm). (2) At smaller separations the dispersion energies and the induction energies are largely quenched by their exchange counterparts, and this case in induction interaction is much more remarkable than in dispersion interaction. (3) Since at shorter distances there exists the strong short-range interaction due to electron transfer which quickly decays and even disappears at larger separations, the two different R-dependency formulae of induction energies were found: one is ca. R-12.7 at short distances, and the other ca. R-7.0 at large separations. The latter R-dependency is similar to that (ca. R-7.2) of dispersion. (4) In the case of strong polar interaction existing in nitramide dimer, the true induction correlation terms of higher order than t(22)indE may be important.

关键词： dispersion energy induction energy nitramide dimer symmetry-adapted perturbation theory

Investigation on oxidation states of rhenium in Re-HEDP

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nuclear Science and Techniques 2003年第3期14卷 174-177页

作者： WANG Wen-Jin, LUO Shun-Zhong, QIAO Jian, LIU Guo-Ping, LIU Ye-Bing (institute of nuclear physics and chemistry, china academy of engineering physics, mianyang 621900) institute of nuclear physics and chemistry China Academy of Engineering Physics Mianyang 621900

The oxidation states of rhenium in Re-HEDP (hydroxyethylidene diphosphonate) were measured bythe methods of extraction and potentiometric titration. The oxidation state of rhenium in Re-HEDP was mostly +4valence, and the Re(Ⅳ)-HEDP was oxidized to Re( Ⅴ)-HEDP when it was titrated by I3- at pH 2.0. In the reductionsystem of Vc+Sn2+ , ReO4- was only reduced by Sn2+, but Vc was oxidized earlier than Sn2+ when it was titrated by I3.

关键词：铼电势滴定氧化态化合价锡放射性同位素肿瘤治疗

In-vivo behavior of tin-radiopharmaceuticals

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nuclear Science and Techniques 2003年第2期14卷 127-130页

作者： HE Jia-Heng, LUO Shun-Zhong, WANG Guan-Quan, YANG Yu-Qing, PU Man-Fei, LIU Guo-Ping (institute of nuclear physics and chemistry, the chinese academy of engineering physics, mianyang 621900) institute of nuclear physics and chemistry the Chinese Academy of Engineering Physics Mianyang 621900

Tin is an essential ingredient of most technetium-99m radiopharmaceuticals but its in-vivo distribution and long-term fate are not well understood. This work describes distribution in mice of several tin-117m labeled compounds. The results indicate that stannic-HEDTMP appears to be the best overall bone localizing agent with very low blood, muscle, kidney, or liver uptake, and its binding to bone is higher than that of tin-117m-DTPA, which make it potentially useful as an agent for skeletal scintigraphy and radiotherapy of bone tumors.

关键词：放射性药品锡骨肿瘤闪烁扫描法放射线疗法

Inhibit the Porosity with Electron Beam Scanning Method in Welding LD10 Aluminum Alloy

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稀有金属材料与工程 2011年第S4期40卷 54-57页

作者： Mo Zhonghai,Wang Yarong,Huang Wenrong institute of Machinery Manufacturing Technology,china academy of engineering physics,mianyang 621900,china china Acad Engn Phys Inst Machinery Mfg Technol Mianyang 621900 Peoples R China

LD10 aluminum alloy is becoming widely used in aeronautics and astronautics industries for the advantages of high specific strength and good mechanical *** alloy is an active metal with low melting point and boiling *** porosity is apt to occur in the processing of electron beam *** this article,the author investigated the influence of electron beam scanning welding parameters (scanning figure,scanning frequency,focus,and welding speed) on porosity.10 mm thick LD10 aluminum alloy were welded and then tested by X-ray *** experiment results indicated that rational parameters would reduce the occurrence opportunity of *** the parameters of circle scanning,high scanning frequency,focus-out,and smaller welding speed,the porosity can be significantly reduced.

关键词： electron beam welding LD10 aluminum alloy porosity

Effects of Processing Parameters on Weld Geometries in Electron Beam Welding Based on Partial Correlation Analysis

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稀有金属材料与工程 2011年第S4期40卷 30-34页

作者： Shen X F,Huang W R,Zhang Y Z institute of Machinery Manufacturing Technology,china academy of engineering physics,mianyang 621900,china china Acad Engn Phys Inst Machinery Mfg Technol Mianyang 621900 Peoples R China

Accelerating voltage,electron beam current,welding speed constitutes the main electron beam welding process parameters,while the penetration depth and depth-width ratio are two of the most important characteristic parameters of the weld *** complex interactions exists between the five variables,so the analysis of a single process parameter on one of weld geometries is affected by the other process parameters,and the impact of these interference parameters should be excluded to find the real relationship between the variables where partial correlation analysis provides such a *** of the accelerating voltage,electron beam current,welding speed of electron beam welding process parameters on weld geometries is analyzed by using partial correlation *** priority order of adjustment of process parameters is obtained,namely:in order to obtain a larger depth-width ratio indicators,it should be taken firstly to increase the beam current and accelerating voltage,and then to raise the welding speed;in order to obtain greater penetration depth,it is preferred to increase the beam current,followed by increasing the accelerating voltage,and reducing the welding speed finally.

关键词： electron beam welding process parameters characteristic parameters of weld morphology partial correlation analysis