湿法锑白的晶型转变

研究了湿法锑白的白度和光敏性。通过真空干燥试验研究，对样品进次了Ｘ射线衍射定量分析，首次发现真空干燥可以使湿法锑白发生晶型转变，由斜方晶体转变为立方晶体。在适宜条件下，其转变率可达９９．６％。转变为立方晶的锑白白度高且见光稳定，光敏性消失。     

爆炸固结加自蔓延高温合成Ti／Al2O3梯度功能材料

采用爆炸固结加自蔓延高温合成（ＳＨＳ）法制备了Ｔｉ／Ａｌ２Ｏ３梯度功能材料（ＦＧＭ），并对所制备的ＦＧＭ的成分、组织和性能进行了研究。实验结果表明，采用该法可制备成分、组织和性能呈梯度分布、且符合设计要求的致密ＦＧＭ。此外还研究了Ｔｉ／Ａｌ２Ｏ３ＦＧＭ合成过程中的反应模式     

Synthesis and crystal structure of an organic-inorganic complex [Cu(DMF)3(H2O)2]2[SiMo12O40]·2H2O

The synthesis and crystal structure of an polyoxometalate-based organic-inorganic complex [Cu(DMF)3(H2O)2]2[SiMo12O40]·2H2O (DMF = N, N-dimethyl formamide) is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper(Ⅱ) centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.     

Synthesis and crystal structure of an organic-inorganic complex [Cu（DMF）3（H2O）2]2[SiMo12O40]·2H2O

The synthesis and crystal smacture of an polyoxometalate-based organic-inorganic complex [Cu（DMF）3（H2O）212[SiMo12O40].2H2O （DMF = N, N-dimethyl formamide） is described in this article. It was characterized using elemental analysis, thermal analysis, infrared, ultraviolet, and electron spin resonance spectroscopic studies. The X-ray crystallography analysis showed that the copper centers are pentacoordinated to show the square pyramidal geometry, and the polyanion [SiMo12O40]4- which is semi-coordinated to the copper（I/） centers prevents the existence of a sixth ligand. In addition, the intracationic hydrogen interaction enhanced the stability of the copper coordination cation.     

燃烧合成—热压制备Al2O3—TiC—ZrO2纳米复合隐瓷的力学性能与显微结构

以TiO2,Al,C,纳米ZrO2粒子为原料,利用燃烧合成-热压工艺制备了Al2O3-TiC-ZrO2纳米复合陶瓷.添加ZrO2可使Al2O3-TiC断裂方式由沿晶断裂转变为穿晶断裂.ZrO2纳米粒子弥散于基体中,其周围产生的应力集中可引发位错,起到亚晶界的作用,并可使位错钉扎、堆积,阻碍位错运动,从而使复合陶瓷的力学性能得到明显改善抗弯强度为706 MPa,提高幅度达19.8%;断裂韧性为6.3 MPa@m1/2,提高幅度18.9%;洛氏硬度为94.4.     

铝热还原氮化法制备TiN-Al2O3复合粉体

本文用Al作还原剂还原氮化TiO2制备了TiN—Al2O3复合粉体。通过对比不同温度下的含氮率和理论含氮率，可以判断反应进行的程度；通过XRD分析研究不同温度下的相变化；通过SEM、EDS分析观察晶粒的形貌和成分。研究结果发现，TiN在1100℃开始生成，1450℃TiN生成反应结束。SEM照片显示细小、不规则的TiN晶粒和多面体Al2O3晶粒相互交叉均匀分布，Al2O3晶粒尺寸10μm左右，TiN晶粒尺寸2μa左右。表明用此方法可以在比较低的温度下合成颗粒细小分散均匀的TiN-Al2O3复合粉体。     

PARTICLES ANALYSIS OF Al_2O_3 PARTICLE REINFORCED ZL202 MATRIX COMPOSITES PREPARED BY IN-SITU REACTION

ZL202 matrix composite reinforced by Al2O3 particles was prepared by combining in-situ reaction and casting techniques. Particles' size in the composites was from 1 to 5 microns in diameter. X-ray diffraction analysis verified that the reinforcing particleswere δ-Al2O3 which belong to γ-Al2O3 series. The wetting angle between matrix andreinforcement was less than 90°. Energy spectrum analysis indicated that the reactionin bell cover pressing process took place not so completely as in flouring stir process. When the reaction was finished, the matrix was still ZL202 alloy in both.processes.     

Thermoelectric properties of p-type (Bi,Sb)2Te3 alloys fabricated by the hot pressing method

P-type (Bi_0.25Sb_0.75)₂Te₃ powders were fabricated by melting/grinding and mechanical alloying processes. Thermoelectric properties of the hot-pressed (Bi_0.25Sb_0.75)₂Te₃ were characterized with the powder processing method, powder size, hot pressing temperature, and the amount of excess-Te dopant. Specimens fabricated by melting/grinding exhibited lower Seebeck coefficient, lower electrical resistivity and higher thermal conductivity, compared to the specimens prepared by mechanical alloying. 3 wt.% excess Te-doped (Bi_0.25Sb_0.75)₂ Te₃, fabricated by melting/grinding and hot pressing at 550°C, exhibited a figure-merit of 3.2 x 10^-3/K. For 1 wt.% excess Te-doped specimen prepared by mechanical alloying and hot pressing at 550°C, a figure-merit of 3.05 x 10^-3/K was obtained.     

原位反应法制备Fe-Cr-Ni/TiC(p)复合材料的组织结构与抗氧化性

利用原位反应法制备了Fe-26Cr-14Ni+3 mass%TiC(p) 和Fe-26Cr-14Ni+6 mass%TiC(p)复合材料.复合材料由平均尺寸为05～5 μm的TiC颗粒与 γ基体组成，TiC中存在α/2［11〖DD(〗-〖DD)〗0］和α/2［01〖DD(〗-〖DD)〗1］型高 密度位错，TiC颗粒与γ相间界面为共格界面，二者存在下列位向关系：(2〖DD(〗-〖DD)〗 20)TiC∥(020)γ，［001］TiC‖［001］γ.1473K下的抗氧化性实验结 果表明，TiC颗粒的存在使复合材料的初始氧化阶段具有短路扩散效应，两种复合材料的氧 化动力学曲线分别符合抛物线和对数增长规律，在稳定氧化阶段，复合材料比基体合金具有 更优良的抗氧化性能，氧化膜主要由多面体状Cr2O3和FeCr2O4相构成.     

Microstructural Observations on 1:2 ordered domain boundaries in Ba(Mg1/3Ta2/3)O3

High resolution transmission electron microscopy (HRTEM) has been used to investigate the detailed microstructures of the antiphase boundaries (APBs) of 1:2 B-site ordered domsins in fully ordered Ba(Mg_1/3Ta_2/3)O₃ ceramic compound. The orientation relationship (102)_I // (012)_II, [010]_I // [100]_II was found between two domains. The ledged coherent interface has formed with (101) plane as an atomic habit plane. The growth ledge which possesses the kinks on ledge structure on the riser has the height of 1.22 nm which is equivalent to three (101) planes. The coalescence of the growth ledges and the genera~ion of these ledges at the structurally faulted region had been found experimentally. New interface model which was coherent and had a growth ledge was constructed based on the experimentally obtained diffraction pattern and HRTEM images and thereafter the lateral growth by the ledge mechanism in the coarsening of ordered phase boundaries was proposed.     

MICROSTRUCTURES AND MECHANICAL PROPERTIES OF IN-SITU Al2O3/TiAl COMPOSITES BY EXOTHERMIC DISPERSION METHOD

In-situ Al2O3/TiAl composites were fabricated by pressure-assisted exothermic disper-sion (PAXD) method from elemental powder mixtures of Ti, Al, TiO2, and Nb2O5.The microstructures and mechanical properties of the as-sintered composites are in-vestigated. The results show that the as-sintered products consist of γ-TiAl, α2-Ti3Al,Al2O3, and NbAl3 phases. Microstrueture analysis indicates that Al2O3 particles tend to disperse on the grain boundaries. Application of a moderate pressure of 35 Mpa at 1200℃ yields Ab2O3/TiAl composites with fine Al2O3 reinforcement and a dis-continuous network linking by Al2O3 particles. The aluminide component has a fine submicron γ+α2 larnellar rnicrostructure. With increasing Nb2O5 content, A1203 par-ticles are dispersed uniformly in the matrix. The hardness of the composites increases gradually, and the bending strength and fracture toughness of the composites reach to the maximum value, respectively.     

Cis-[Pt(NH_3)_2(H_2O)_2](NO_3)_2与1,1-环丁烷二羧酸钠形成的一种新的Pt(Ⅱ)配合物(英文)

从Cis-[Pt(NH3)2(H2O)2](NO3)2 与1,1-环丁烷二羧酸钠的化学反应中,分离出一种新的Pt(II)配合物,通过元素分析、红外光谱, 质谱和高效液相色谱的分析测试,初步推测结构为顺式-四氨-μ-二(1,1-环丁烷二羧酸根-O1,O2)合二铂的新化学结构式.     

退火温度对Fe72.5Cu1Nb2V2Si13.5B9软磁合金微结构的影响

用Ｘ射线射,透射电子显微镜,数字图像分析等实验技术,系统研究了快淬制制备的Ｆｅ７２．５Ｃｕ１Ｎｂ２Ｖ２Ｓｉ１３．５Ｂ９非晶条带经５００－７５０℃０．５ｈ退火后合金的相组成,晶格参数和晶粒尺寸随温度的变化规律。结果表明,在５３０－５４５℃,退火０．５ｈ,电子数字定量金相测量得到的α－Ｆｅ纳米固溶相平均晶粒尺寸为１３．７－１４．９ｎｍ,当退火温度高于５６０℃时,晶粒体大速度显著磁特性。 时,α－Ｆｅ（     

MnO2和Nb2O5掺杂Pb（Mn1/3Sb2/3）0.05Zr0.47Ti0.48O3压电陶瓷性能的研究

探讨了MnO2和Nb2O5掺杂对Pb（Mn1/3Sb2/3）0.05Zr0.47Ti0.48O3（PMSZT）材料相组成、显微结构、电性能及温度稳定性的影响.结果发现：合成温度900℃,可以得到钙钛矿结构;随着掺杂量的增大,四方相的含量减少,准同型相界向三方相移动;当MnO2过量0.1%,Nb2O5掺杂0.05%（均为质量分数）时,εT33/ε0,d33和Kp达到最佳值;随着MnO2和Nb2O5掺杂量增加,Qm值下降,谐振频率变化率随温度变化由正到负.     

Thermodynamics of Cu(Ⅱ)-NH3-NH4Cl-H2O system

The thermodynamics of a complex solution system, Cu(Ⅱ)-NH3-NH4Cl-H2O, was presented both theoretically and experimentally. Firstly, according to the principles of simultaneous equilibrium and aqueous electronic charge neutrality of the system, a nonlinear mathematical thermodynamic model with multi-members was set up. In this model, there were six unknowns: pH value, concentration values of free Cl-, free NH3, total concentration values of Cu2 , Cl- and NH3, four equilibrium equations and three equilibrium equations of total quantum of Cu2 , Cl- and NH3, as well as an equilibrium equation of electric charge, were involved in the model. Then after specifying the values of total concentrate of NH3 and Cl-, the model was solved precisely using MATLAB language, and the other four unknowns were obtained. According to the values obtained above, various valuable figures regarding thermodynamic relation of the system were protracted also with MATLAB, including two and three dimensions figures. These figures and data can supply the theoretic conference for optimizing the ratio of leaching reagents in copper extraction through ammonia hydrometallurgy. Finally, the solubility of CuO were measured in the system of NH3-NH4Cl-H2O. The results show that the model and the thermodynamic data obtained are reliable.     

Preparation of basic nickel carbonate particles in solution system of Ni( Ⅱ )-NH3-CO2-3-H2O

Based on the principles of simultaneous equilibrium and mass balance, a series of thermodynamic equilibrium equations of Ni( Ⅱ )-NH3-CO2-3-H2O system at ambient temperature were deduced theoretically and the thermodynamic diagrams of lg[Ni]T versus pH at different solution compositions were drawn, which was quite effective to explain the formation mechanism of precipitation particles with different microscopic shapes. When pH of the solution is below 7.0, free nickel ions are dominant and when the precipitant is added, the fast coagulation will take place leading to the loose flocculation particles. While pH is above 7.0, because of the coordination of nickelion with ammonia, the precipitation proceeds slowly accompanying with the release of Ni2 from the multi-coordinated Ni(NH3)2 n (n= 1, 2, …, 6), which easily leads to the formation of the dense spherical particles.     

微波辐射Mg(OH)2制备轻质活性MgO新工艺

探讨了微波辐射Mg(OH)2制备轻质活性MgO的可行性，研究了微波功率、微波辐射时间、物料重量对Mg(OH)2分解率的影响，得到了微波辐射Mg(OH)2制备轻质活性MgO的最佳工艺：微波功率800W，微波辐射时间8分钟．物料重量4克，其煅烧时间只有传统方法的1／10，Mg(OH)2分解率为99．62％，氧化镁含量95．09％，碘吸附值为78．68mg／g，产品指标达到了沪Q/HGll-238-82一极标准。     

Sb2O3掺杂（Na0．84K0．16）0．5Bi0．5TiO3无铅压电陶瓷的压电与介电性能研究

采用传统陶瓷的制备方法，制备出Sb2O3掺杂的（Na0．84K0．16）0．5Bi0．5TiO3的无铅压电陶瓷。XRD分析表明，Sb2O3的掺杂量在0．1％～0．6％（质量分数）范围内都能够形成纯钙钛矿（ABO3）型固溶体。陶瓷材料的介电常数-温度曲线显示陶瓷在升温过程中存在两个介电常数温度峰，结合不同温度下的电滞回线观测，认为两个介电峰分别是材料的铁电-反铁电和反铁电-顺电相变，宽化的介电峰同时也表明所研究陶瓷具有驰豫铁电体特征。测试了不同组成陶瓷的压电性能，在Sb2O3掺杂量为0．1％时陶瓷的压电常数d33=124pC／N，为所研究组成中的最大值，平面机电耦合系数kp=24．87％，略有下降，材料的介电常数ε33^T／ε0和介质损耗tanδ则随掺杂量的增加而增加。     

燃烧合成Cr-(Al,Cr)2O3金属陶瓷的耐磨性能

用热爆燃烧合成法结合熔体施压致密化,制备了相对密度约90％的Cr-（Al,Cr）2O3金属陶瓷,金属Cr颗粒均匀弥散分布于陶瓷板片间或板片内,尺寸可达200nm左右．研究了金属陶瓷的耐磨性能．结果表明,干摩擦条件下,金属陶瓷具有优良的耐磨性能;磨损体积与稀释剂Al2O3加入量和过量Cr2O3的含量有关,两者合理搭配可使Cr-（Al,Cr）2O3的磨损体积小于粉末烧结氧化铝陶瓷的磨损体积．磨损机理主要是块状剥落．油润滑后,147N载荷下,金属陶瓷经6000m滑动距离仍基本无磨损体积损失;随载荷提高,磨损体积有所增大,但仍比Cr12MoV钢小一个数量级以上．     

复合体材料CuFe2O4-Pb(Mg1/3Nb2/3)O3的内耗和介电损耗

用传统的固相反应方法制备了CuFe2O4-Pb(Mg1／3Nb2／3)O3复合体材料陶瓷,用X射线衍射确定了复合体材料中各相的存在．用双端振动簧法研究了样品在-200—400℃的音频内耗谱,在37．6℃发现一个很大的内耗峰P1,并伴随着约9％的模量的软化,表明了相变的存在．在室温下,测量了介电常数ε′和介电损耗tanδ随频率变化的关系;同时,测量了复合体材料的介电常数和介电损耗随温度的变化关系,进一步验证P1峰由立方到四方的相变引起．最后给出样品的磁滞回线。