移动加热器法生长CdMnTe晶体的生长界面（英文）

研究了移动加热器法生长CdMnTe晶体的生长界面。采用传统摇摆炉和垂直Bridgman炉合成多晶原料,并比较了不同多晶原料对移动加热器法生长界面的影响。结果显示,采用垂直Bridgman法合成多晶生长的CdMnTe晶体(CMT2)相对于传统摇摆炉合成多晶生长的晶体(CMT1),其生长界面较为光滑且凹面曲率更低。分析了生长界面对CdMnTe晶体的Mn成分和Te夹杂相分布的影响。CMT2晶体Mn的径向成分分凝和Te夹杂相密度及尺寸均小于CMT1晶体。总之,垂直Bridgman法合成多晶原料能明显改善生长界面的形态,有利于降低移动加热器法生长Cd Mn Te晶体的Te夹杂相和Mn的成分分凝,提高晶体的质量。     

纳米四方多晶氧化锆粉末的超强碱共沉淀法制备及性能表征

采用引入有机添加剂的超强碱共沉淀法可制备出粉末粒子尺寸为10nm左右的高纯纳米多晶氧化锆粉末。通过控制适当的工艺条件，得到了室温稳定的纳米四方／立方多晶氧化锆粉末。用X射线荧光光谱、X射线衍射、透射电镜、粒度分析仪等手段对粉末性能进行了表征。实验结果表明：超强碱共沉淀法所制备的粉末具有纯度高、氯离子等杂质少等特点；该粉末在室温和小于873K热处理时，均以稳定的立方或四方相存在；经873K处理的粉末粒子尺寸为10nm左右；在1123K处理后，形成固溶完全的稳定纳米四方多晶氧化锆粉末，粒子尺寸小，分散性好，粒度分布窄。与其它湿化学方法相比，添加聚合物的超强碱共沉淀法具有工艺操作简单、节约资源和环境污染小的优点。     

(Pb_(0.5)Sr_(0.5))TiO_3粉体与薄膜的合成、结构与电性能研究(英文)

使用溶胶凝胶法合成(Pb0.50Sr0.50)TiO3(缩写为PST)粉体和薄膜。用X射线衍射(XRD)和扫面电镜(SEM)观察PST粉体的相形成和形貌特征。结果表明,800℃退火处理的凝胶样品还有中间相碳酸盐存在;850℃退火的干凝胶样品,晶化完成后为多晶钙钛矿结构,而650℃经快速热处理的薄膜样品为多晶结构,平均晶粒尺寸为60nm。PST薄膜在100kHz频率测量情况下,介电常数与损耗分别为561.5和0.022。     

沉积和退火温度对多晶ZnO薄膜结构特性的影响

采用RF反应溅射法在Si（111）衬底上制备出了沿C轴高度取向的多晶ZnO薄膜。通过对ZnO薄膜的X射线衍射（XRD）分析，研究了沉积温度及退火对多晶ZnO薄膜取向性、晶粒大小和应力的影响。结果表明，衬底温度和退火温度对多晶ZnO薄膜的晶体结构影响显著。适当的提高衬底温度或适当的增加退火温度都能有效地改善ZnO薄膜的结构特性，但增加退火温度更有优势。同时原子力显微镜观察表明，退火能有效地降低ZnO薄膜的表面粗糙程度。     

稀土La对导电陶瓷BaPbO3组织和电性能的影响

采用化学液相共沉淀法制备了掺稀土La的BaPbO3导电陶瓷；用XRD及SEM对粉末的结构和组织进行了研究，从而确定了液相共沉淀法制取Ba1-xLaxPbO3的合成温度：同时讨论了稀土La对BaPbO3粉末合成过程及其电性能的影响。结果表明：采用液相共沉淀法能明显降低BamLaxPbO3粉末的合成温度，提高粉体的合成率，其合成温度大约在650℃左右：添加稀土La对BaPbO3的电阻率的影响呈“W”形状变化，当x=10％mol时Ba1-xLaxPbO3的焙烧温度、组织、电阻率均达到最佳。     

油酸对化学共沉淀法制备La0.7（Ca0．53Sr0．47）0.3MnO3多晶的电阻温度系数的影响

研究了化学共沉淀法制备La0.7(Ca0.53Sr0.47)0.3MnO3多晶过程中添加油酸作分散剂的工艺,用DTG/TA、XRD和R-T(电阻-温度)系统测试了所制样品的性能.结果表明:添加油酸,共沉淀法制备La0.7(Ca0.53Sr0.47)0.3MnO3多晶比不添加的烧结温度低,也比同相反应法低.油酸的用量为0.1～O.2L/mol能明显提高La0.7(Ca0.53Sr0.47)0.3MnO3的电阻一温度转变点和电阻温度系数.     

Ni3P／Ni复相纳米材料晶格畸变的热回复行为研究

对采用非晶晶化法制备的Ｎｉ－Ｐ合金复相纳米晶体样品在不同温度下进行等温退火处理,利用Ｘ射线衍射分别对样品中Ｎｉ固溶体和Ｎｉ３Ｐ化合物的晶格参数随退火温度,退火材料的变化进行了测试。发现退火处理可使晶格畸变有所回复,但退火温度的高低使得两纳米晶体相的微观结构变化行为明显不同,利用纳米晶体的热力学状态对这种效应进行了解释。     

二氧化锆合成宝石产业现状和发展

对二氧化锆合成宝石（ZrO2晶体）的生产工艺及发展现状进行了综述。目前，我国人工合成立方ZrO2宝石的生产工艺采用先进的冷坩埚凝壳熔炼法，单炉产量达到800kg，年产ZrO2晶体4500t，已成为亚洲乃至世界人工ZrO2宝石的制造中心。但是，产品质量仍属于中低档范围，且生产能力饱和，因此，发展ZrO2单晶、多晶等用于电子工业等行业的高端产品，是合成宝石行业今后重要的发展方向。     

浸渍型钡钨阴极用高性能铝酸盐研究

采用固相反应法和化学液相共沉淀法合成钡钨阴极电子发射材料铝酸盐.XRD,TG-DSC分析表明:液相共沉淀法最佳合成温度为1100℃,比高温固相反应法的合成温度降低了150℃;产物主晶相为Ba5CaAl4O12合成的盐制备成阴极,化学液相共沉淀法的脉冲发射电流密度25.3865 A/cm2,是固相反应法的2倍;平均蒸散速率为Vevap=5.04×10-8(g·cm-2)·s-1.液相法合成的铝酸盐满足了钡钨阴极的使用要求.     

强磁场对非线性光学晶体ZnGeP_2生长及性能的影响

按化学计量比并富P2%配料,通过改进的单温区合成法合成出高纯、单相的ZnGeP2多晶原料,在无磁场、6 T匀强磁场和上、下梯度磁场条件下,使用坩埚下降法成功生长出ZnGeP2单晶。研究表明,施加6 T匀强磁场和上、下梯度磁场后,ZnGeP2晶体依次沿(116)、(112)和(220)取向,与无磁场下晶体取向不同;ZnGeP2晶体成分沿纵向方向在强磁场中比无磁场中波动明显;红外透过率在匀强和上梯度磁场中均有明显提高,下梯度磁场中变化不明显;电阻率在匀强和上梯度磁场中有所下降,而下梯度磁场中则有所升高。     

Effects of Post-weld Heat Treatment on Microstructure,Mechanical Properties and the Role of Weld Reinforcement in 2219 Aluminum Alloy TIG-Welded Joints

In as-welded state, each region of 2219 aluminum alloy TIG-welded joint shows diff erent microstructure and microhardness due to the diff erent welding heat cycles and the resulting evolution of second phases. After the post-weld heat treatment, both the amount and the size of the eutectic structure or θ phases decreased. Correspondingly, both the Cu content in α-Al matrix and the microhardness increased to a similar level in each region of the joint, and the tensile strength of the entire joint was greatly improved. Post-weld heat treatment played the role of solid solution strengthening and aging strengthening. After the post-weld heat treatment, the weld performance became similar to other regions, but weld reinforcements lost their reinforcing eff ect on the weld and their existence was more of an adverse eff ect. The joint without weld reinforcements after the post-weld heat treatment had the optimal tensile properties, and the specimens randomly crack in the weld zone.     

The First Phase of the SRIF Industrialized Base in ＂West Area＂ Has Been Put into Operation

After nearly two years＇ tense construction, the first phase of industrialized base of Shenyang Research Institute of Foundry （SRIF）, located at the Tiexi Casting and Forging Industrial Park in the west of Tiexi District, has now been completed and formally put into operation.     

新型的治疗阿尔茨海默氏症药物(1-二甲基磷酰基-2,2,2-三氯)-乙基-1-醇烟酸醋对体外神经细胞的作用

目的: 观察本实验室合成的一种治疗阿尔茨海默氏症(AD)的药物(1-二甲基磷酰基-2, 2, 2 -三氯)-乙基^-1-醇烟酸醋(NMF),对体外培养的皮层神经细胞活性的影响以及对海人藻酸(KA)所致的神经损伤的保护作用。方法: 采用体外培养皮层神经元的方法,解剖分离 15 d胚胎小鼠皮层神经细胞, 接种于 96孔板,48 h 后加药并培养 72 h,以 MIT 法 观察 NMF 对小鼠皮层神经细胞活性的影响;同时将接种于 24 孔板的细胞预先给予 NMF,d 3 时加或不加KA处理后,以台盼蓝染色鉴别并计数死、活细胞,可得出细胞的存活率。结果: NMF 明显促进胎鼠皮层神经元活性,其中 NMF1、0. 1、10nmol·L^-1促进神经元活性增殖率分别高达 34.7%、37.4%、36. 7%, NMF 明显促进正常胎鼠皮层神经元存活卒,与对照组比较,10nmol·L^-1 NMF 对皮层神经元的存活率分别提高 39.3%、73.5%。 NMF能显著 对抗 KA 所致的神经元损伤,与 KA 损伤组相比, NMF0.1、10、10nmol·L^-1对损伤皮层神经元的保护率分别为 77.30%、80.10%、84.15%。结论: NMF 明 显促进胎鼠皮层神经元的洁性、提高正常皮层神经元,的存活卒,并能有效地保护KA所致的神经元损伤,提示 NMF 是一种很有潜力的治疗 AD 的药物。     

THERMODYNAMICS STUDY ON THE DECOMPOSITION OF CHROMITE WITH KOH

Institute of Process Engineering, Chinese Academy of Sciences, China, has proposed a method for oxidative leaching of chromite with potassium hydroxide. Understanding the mechanism of chromite decomposition, especially in the potassium hydroxide fusion, is important for the optimization of the operating parameters of the oxidative leaching process. A traditional thermodynamic method is proposed and the thermal decomposition and the reaction decomposition during the oxidative leaching of chromite with KOH and oxygen is discussed, which suggests that chromite is mainly destroyed by reactions with KOH and oxygen. Meanwhile, equilibrium of the main reactions of the above process was calculated at different temperatures and oxygen partial pressures. The stable zones of productions, namely, K2CrO4 and Fe2O3, increase with the decrease of temperature, which indicates that higher temperature is not beneficial to thermodynamic reactions. In addition, a comparison of the general alkali methods is carried out, and it is concluded that the KOH leaching process is thermodynamically superior to the conventional chromate production process.     

INFLUENCE OF HEAT TREATMENT ON DAMPING BEHAVIOUR OF THE MAGNESIUM WROUGHT ALLOY AZ61

The effect of isochronal heat treatments for 1h on variation of damping, hardness and microstructural change of the magnesium wrought alloy AZ61 was investigated. Damping and hardness behaviour could be attributed to the evolution of precipitation process. The influence of precipitation on damping behaviour was explained in the framework of the dislocation string model of Granato and Lücke.     

Three-Dimensional Growth of Coherent Ferrite in Austenite: A Molecular Dynamics Study

Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases. As a key feature of microstructure, the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys. This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation. We found that the ferrite grain tends to grow into an elongated plate-like shape, independent of its initial confi guration. The fi nal shape of the ferrite is closely related to the misfi t between the two phases, with the longest direction and the broad facet of the plate being, respectively, consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC) method. The strain energy calculation in the framework of Eshelby's inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable. It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems.     

Effect of Rare Earth Doping on Impedance,Modulus and Conductivity Properties of Multiferroic Composites:0.5(BiLa_xFe_(1-x)O_3)–0.5(PbTiO_3)

The Lanthanum-doped bismuth ferrite–lead titanate compositions of 0.5(Bi LaxFe1-xO3)–0.5(Pb Ti O3)(x = 0.05,0.10,0.15,0.20)(BLxF1-x-PT) were prepared by mixed oxide method.Structural characterization was performed by X-ray diffraction and shows a tetragonal structure at room temperature.The lattice parameter c/a ratio decreases with increasing of La(x = 0.05–0.20) concentration of the composites.The effect of charge carrier/ion hopping mechanism,conductivity,relaxation process and impedance parameters was studied using an impedance analyzer in a wide frequency range(102–106Hz) at different temperatures.The nature of Nyquist plot confirms the presence of bulk effects only,and non-Debye type of relaxation processes occurs in the composites.The electrical modulus exhibits an important role of the hopping mechanism in the electrical transport process of the materials.The ac conductivity and dc conductivity of the materials were studied,and the activation energy found to be 0.81,0.77,0.76 and 0.74 e V for all compositions of x = 0.05–0.20 at different temperatures(200–300 °C).     

Using Finite Element and Contour Method to Evaluate Residual Stress in Thick Ti-6Al-4V Alloy Welded by Electron Beam Welding

This work was to reveal the residual stress profile in electron beam welded Ti-6Al-4V alloy plates(50 mm thick) by using finite element and contour measurement methods.A three-dimensional finite element model of 50-mmthick titanium component was proposed,in which a column–cone combined heat source model was used to simulate the temperature field and a thermo-elastic–plastic model to analyze residual stress in a weld joint based on ABAQUS software.Considering the uncertainty of welding simulation,the computation was calibrated by experimental data of contour measurement method.Both test and simulated results show that residual stresses on the surface and inside the weld zone are significantly different and present a narrow and large gradient feature in the weld joint.The peak tensile stress exceeds the yield strength of base materials inside weld,which are distinctly different from residual stress of the thin Ti-6Al-4V alloy plates presented in references before.     

Microstructures and Tensile Properties of Ultrafine-Grained Ni–(1–3.5) wt% SiC_(NP) Composites Prepared by a Powder Metallurgy Route

Silicon carbide nanoparticle-reinforced nickel-based composites(Ni–Si CNP),with a Si CNPcontent ranged from1 to 3.5 wt%,were prepared using mechanical alloying and spark plasma sintering.In addition,unreinforced pure nickel samples were also prepared for comparative purposes.To characterize the microstructural properties of both the unreinforced pure nickel and the Ni–Si CNPcomposites transmission electron microscopy(TEM) was used,while their mechanical behavior was investigated using the Vickers pyramid method for hardness measurements and a universal tensile testing machine for tensile tests.TEM results showed an array of dislocation lines decorated in the sintered pure nickel sample,whereas,for the Ni–Si CNPcomposites,the presence of nano-dispersed Si CNPand twinning crystals was observed.These homogeneously distributed Si CNPwere found located either within the matrix,between twins or on grain boundaries.For the Ni–Si CNPcomposites,coerced coarsening of the Si CNPassembly occurred with increasing Si CNPcontent.Furthermore,the grain sizes of the Ni–Si CNPcomposites were much finer than that of the unreinforced pure nickel,which was considered to be due to the composite ball milling process.In all cases,the Ni–Si CNPcomposites showed higher strengths and hardness values than the unreinforced pure nickel,likely due to a combination of dispersion strengthening(Orowan effects) and particle strengthening(Hall–Petch effects).For the Ni–Si CNPcomposites,the strength increased initially and then decreased as a function of Si CNPcontent,whereas their elongation percentages decreased linearly.Compared to all materials tested,the Ni–Si CNPcomposite containing 1.5% Si C was found more superior considering both their strength and plastic properties.     

Directional Growth of Tin Crystals Controlled by Combined Solute Concentration Gradient Field and Static Magnetic Field

A new method was introduced to achieve directional growth of Sn crystals. Microstructures in liquid(Pb)/liquid(Sn) diffusion couples were investigated under various static magnetic fields. Results show that the β-Sn crystals mainly reveal an irregular dendritic morphology without or with a relatively low static magnetic field(B0.3 T). When the magnetic field is increased to 0.5 T, the β-Sn dendrites close to the final stage of growth begin to show some directional character. With a further increase in the magnetic field to a higher level(0.8–5 T), the β-Sn dendrites have an enhanced directional growth character, but the dendrites show a certain deflection. As the magnetic field is increased to 12 T, the directional growth of the β-Sn dendrites in the center of the couple is severely destroyed. The mechanism of the directional growth of the β-Sn crystals and the deflection of the β-Sn crystals with the application of static magnetic field was tentatively discussed.