高应变率下U-Nb合金的断裂组织特征

利用内部爆炸加载方法对U-Nb合金进行爆破试验，对爆破试验产生的破片进行回收，并对U-Nb合金破片进行一些微观检测分析，从而初步研究在爆炸加载下U-Nb合金的微观断裂机制。     

YBCO涂层导体用Ni5W基带的制备和立方织构的发展

为了制作能满足YBCO涂层导体（coated conductor）所需要的高强度、低磁性的立方织构基带，本工作用粉末冶金方法制作了Ni-5at％W合金基带．为评估基带中立方织构的发展，用March-Dollase函数对各种热处理样品的择优取向度进行了研究，结果与用X射线极图法和电子背散射衍射法得到的结果基本一致．研究结果表明，在实验中所用的工艺参数范围内，随总加工率和热处理温度的提高，基带中立方织构百分数明显增高．提高总加工率实际增加了冷加工样品中立方织构晶粒或立方核心的数量．实验中得到了较好的和实用的工艺制度，用这种工艺可以制作出具有99％～100％立方织构百分数，并具有很好一致取向度的Ni5W基带．     

The structural,elastic, and electronic properties of ZrxNbl-xC alloys from first principle calculations＊

The structural, elastic, electronic, and thermodynamic properties of ZrxNbl xC alloys are investigated using the first principles method based on the density functional theory. The results show that the structural properties of Zr~.Nb1 xC alloys vary continuously with the increase of Zr composition. The alloy possesses both the highest shear modulus （215 GPa） and a higher bulk modulus （294 GPa）, with a Zr composition of 0.21. Meanwhile, the Zr0.2! Nb0.79C alloy shows metallic conductivity based on the analysis of the density of states. In addition, the thermodynamic stability of the designed alloys is estimated using the calculated enthalpy of mixing.     

第一性原理研究Hg2CuTi型Heusler合金Ti2FeB的磁性和半金属性

基于密度泛函理论的GGA计算,我们具体研究了Hg2 CuTi型Heusler合金Ti2 FeB的电子结构和磁性质,结果发现Ti2FeB合金在其费米面处存在100％的自旋极化,并在5.1～6.2(A)晶格范围内被保留.Ti2FeB具有大约0.5 eV的半金属带隙和1μB的原胞总磁矩,是一个稳定的半金属铁磁体.此外,我们的研究也表明RKKY型间接交换和d电子杂化在决定合金磁性质中起决定性作用.     

西北旱田黄土对Pb(Ⅱ)和氯吡硫磷复合污染的共吸附机制研究

通过静态批次实验研究旱田黄土对Pb(Ⅱ)和氯吡硫磷的共吸附行为,使用SEM,FTIR,XRD和理论分析揭示共吸附机制。实验结果发现:黄土对Pb(Ⅱ)和氯吡硫磷的共吸附符合Langmuir等温线方程,经计算得出的理论吸附容量qm分别为12.5和0.64mg.g-1,准二级动力学方程能更好地描述反应行为。吸附反应后,黄土表面形貌变化很小,FTIR图谱中的某些波峰红移、消失或强度减弱,综合XRD图谱及理论分析,认为:旱田黄土对Pb(Ⅱ)的吸附为表面配位络合和范德华力的作用,以化学吸附为主;而氯吡硫磷的去除涉及到黄土有机质对氯吡硫磷大分子的截留作用,以及氢键、范德华力的作用,以物理吸附为主,兼有化学吸附的贡献。旱田黄土有机质对Pb(Ⅱ)和氯吡硫磷的吸附有重要贡献。     

ICP-AES测定铜合金中的铜及10种杂质元素

建立了ICP-AES同时测定铜合金中铜及杂质元素磷、硅、锰、铁、镍、钴、锌、铅、铝、锡11种元素的分析方法,通过对样品溶解方法、元素分析谱线的选择和仪器分析参数进行试验比较,确定了实验条件,并对铜合金标准样品进行了精密度和回收率实验.结果表明,相对标准偏差小于3.0％,回收率在90％-110％之间.该方法快速简便,准确度高,可以满足日常检验的分析要求.     

Structural, electronic, and optical properties of ZnOl_xSex alloys using first-principles calculations

The structural, electronic, and optical properties of binary ZnO, ZnSe compounds, and their ternary ZnOl_xSex alloys are computed using the accurate full potential linearized augmented plane wave plus local orbital （FP-LAPW ＋ lo） method in the rocksalt （B 1） and zincblende （B3） crystallographic phases. The electronic band structures, fundamental energy band gaps, and densities of states for ZnO1_xSex are evaluated in the range 0 〈 x 〈 1 using Wu-Cohen （WC） generalized gradient approximation （GGA） for the exchange-correlation potential. Our calculated results of lattice parameters and bulk modulus reveal a nonlinear variation for pseudo-binary and their ternary alloys in both phases and show a considerable deviation from Vegard＇s law. It is observed that the predicted lattice parameter and bulk modulus are in good agreement with the available experimental and theoretical data. We establish that the composition dependence of band gap is semi-metallic in B1 phase, while a direct band gap is observed in B3 phase. The calculated density of states is described by taking into account the contribution of Zn 3d, O 2p, and Se 4s, and the optical properties are studied in terms of dielectric functions, refractive index, reflectivity, and energy loss function for the B3 phase and are compared with the available experimental data.     

CuCrZr合金质子辐照效应的模拟研究

基于Monte Carlo方法,跟踪一大批入射粒子的运动,模拟1~10 Me V质子辐照下质子与CuCrZr合金的相互作用,计算出合金的阻止本领、能量传递、能量损失、射程、空位分布情况以及合金的辐照损伤分别与辐照深度、质子能量的关系,通过模拟CuCrZr合金在聚变反应中的工作环境,分析热沉材料的失效机理.研究结果表明:质子能量在1~10 Me V时,质子与CuCrZr合金发生非弹性碰撞,能量损失以电离能损失为主,表现出很好的抗辐照性能;质子在合金中的峰值深度随质子能量增加而增加,且近似指数关系,峰值深度为2~250μm;入射质子能量达到Me V级别时,溅射产额为零,CuCrZr合金可以很好的避免器壁的侵蚀;合金中空位的个数与入射质子能量呈线性关系,合金中空位和质子在合金中的分布具有同步性;质子损伤效率在合金深度方向呈现高斯分布,损伤最大值位置与辐照深度接近,随着入射质子能量的增加损伤效率最大值不断减小.     

偏磷酸根(PO-3)对氟铝酸盐玻璃透光性能影响

在氟铝酸盐玻璃（AMCSBY）中引入Ba(PO3）2替代BaF2,替代公式为10MgF2-20CaF2-(10-x)BaF2-10SrF2-15YF3-35AlF3-xBa(PO3)2(x=,2,4,6,8)。对玻璃进行了差热分析，结果表明，在氟铝酸盐玻璃中引入偏磷酸盐使玻璃形成能力大大提高；测量了玻璃从紫外到红外的透过光谱和紫外吸收光谱，在玻璃中引入偏磷酸钡使玻璃中红外透过能力下降，红外吸收边带移向短波段，玻璃紫外透过能力得到提高。紫外吸收边带移向紫外波段，由于PO3^-的影响，O－H吸收峰由2830nm移到3145nm。     

Phase transition and pitting corrosion behaviour for Mo—implanted aluminium

Molybdenum ions are implanted into aluminium with high ion flux and high dose at elevated temperatures of 200℃, 400℃ and 500℃. Due to the high temperature and high flux of vacancies and interstitial atoms, the atom diffusion and chemical effects are enhanced during the ion implantation. The effects increase with increasing ion flux and dose, so that new phase formation and phase transition emerge noticeably. X-ray diffraction analysis shows that when the aluminium is implanted with Mo ions at a low ion flux (25μA/cm²), the Al₅Mo alloy is formed. The atomic ratio of Mo/Al of the Al₅Mo phase is close to 20%. When the aluminium is implanted with Mo ions at a high ion flux (50μA/cm²), the phase transition from Al₅Mo to Al₁₂Mo appears, and the latter is dominant, which is determined to be the final phase. The ratio of Mo/Al in Al₁₂Mo is 7.7%. Rutherford backscattering spectroscopy indicates also that the Mo/Al atom ratio is ～7% to ～8% in Mo-implanted aluminium. The atomic ratios of the constituents in Al₅Mo and Al₁₂Mo are of stoichiometric composition for these alloys. The thicknesses of the Al₁₂Mo alloy layers for Mo-implanted Al with ion doses of 3×10¹⁷/cm² and 1×10¹⁸/cm² are 550nm and 2000nm, respectively. The pitting corrosion potential V_p increases obviously. It is clear that due to the formation of Al₁₂Mo alloy layer, the pitting corrosion resistance is enhanced.