材料期刊网

渗透结晶型防护剂浸涂对钢筋混凝土耐久性影响研究

萧彧星1 , 王树宗1 , 王利锋2 , 萧弘烨3

腐蚀学报（英文）

    分析了钢筋混凝土腐蚀破坏的主要原因是钢筋腐蚀导致的混凝土胀裂.为保护钢筋混凝土研制了一种水性硅酸盐溶胶型涂料并研究了该涂料对混凝土内置网筋的保护作用及经涂料涂覆的混凝土氯离子渗透性和高压渗水性能.结果表明，涂履水性硅酸盐溶胶型涂料可明显提高与改善混凝土的耐久性.

关键词: 钢筋混凝土 , hydrophilic silicate sol , paint

台湾烨联钢铁公司订购二十辊轧机

魏立群

上海金属 doi:10.3969/j.issn.1001-7208.2000.06.017

关键词:

台湾烨和联合钢公司又建一套20辊轧机

上海金属

关键词:

火焰原子吸收光谱法测定云冈石窟风化岩石中钙铜铁锰

刘月成 , 王尚芝 , 李海 , 杨成全 , 樊俊莉

冶金分析 doi:10.3969/j.issn.1000-7571.2010.02.008

采用HF-HNO_3-HClO_4混酸消化样品,HNO_3溶解盐类,火焰原子吸收光谱法直接测定试液中钙、铜、铁、锰的含量.对共存离子的干扰情况进行了考察,发现大量的Si对测定有干扰,在处理样品时通过生成SiF_4除去;磷、铝、钛等元素对钙的化学干扰,通过加入释放剂SrCl_2消除.背景吸收使用氘灯扣除.采用标准曲线法测定,Ca、Cu、Fe、Mn的校准曲线的线性范围分别为0.00～20.00μg/mL、0.00～6.00弘g/mL、0.00～10.00 μg/mL、0.00～6.00μg/mL,检出限分别为0.000 3μg/mL、0.001 3 μg/mL、0.002 6μg/mL、0.006 9 μg/mL.方法用于云冈石窟风化岩石中钙、铜、铁、锰的测定,相对标准偏差分别为2.8%、3.0%、1.4%、2.9%,加标回收率在96%～110%之间.

关键词: 火焰原子吸收光谱法 , 钙 , 铜 , 铁 , 锰 , 风化岩石 , 云冈石窟

Dy3+在Ba3La(BO3)3 中的光致发光

彭夷安 , 曹小妹 , 雷春华 , 刘利民 , 李其华 , 廉世勋

中国稀土学报

研究了Ba3La(BO3)3 基质中Dy3+ 的光致发光特性; 探讨了RE3+的电荷半径比(z/r)和Ce3+, Dy3+ 含量对Dy3+ 发光强度及发光颜色的影响; 分析了Ba3La(BO3)3 中Ce3+ 对Dy3+ 发光的敏化作用; 确定了Dy3+ 的 4F9/2→6H15/2及4F9/2→6H13/2跃迁发射的浓度猝灭机制均为电偶极-电四极相互作用.

关键词: 发光学 , Dy3+ , Ba3La(BO3)3 , 光致发光 , 浓度猝灭 , 稀土

Optical spectra of Ln(3+)(Nd3+, Sm3+, Dy3+, Ho3+, Er3+)-doped Y3GaO6

Journal of Luminescence

Ln(3+) (Ln = Nd, Sm, Eu, Gd, Dy, Ho, Er)-doped Y3GaO6 compounds were prepared by solid-state reaction, and their optical spectra such as absorption, photoluminescence, excitation and time-resolved spectra have been measured for Ln Nd, Sm, Dy, Ho, Er. X-ray powder diffraction shows that the lattice parameters of the compounds (Y(0.96)Ln(0.04))(3)GaO6 decrease with the decrease of the radii of trivalent Ln(3+) ions, indicating that Ln(3+) ions have substituted for y(3+) ions in the lattice. Optical spectra show that there are obvious absorptions at ultraviolet to visible region. The strong emissions in visible and infra-red region show that Y3GaO6 is a suitable host for rare-earth-doped laser crystal and phosphor materials. (C) 2004 Elsevier B.V. All rights reserved.

关键词: crystal-field;absorption-spectra;luminescence;y3ga5o12;glasses;garnet;y2o3;ions;laf3;tb3

Subsolidus phase relations in the ZnO-MoO3-B2O3, ZnO-MoO3-WO3 and ZnO-WO3-B2O3 ternary systems

Journal of Alloys and Compounds

The subsolidus phase relations in the ZnO-MoO3-B2O3, ZnO-MoO3-WO3 and ZnO-WO3-B2O3 ternary systems have been investigated by the means of X-ray powder diffraction (XRD). There is no ternary compound in all the systems. There are five binary compounds and five tie lines in the ZnO-MoO3-B2O3 system. This system can be divided into six 3-phase regions. There are three binary compounds and three tie lines in the ZnO-MoO3-WO3 system. This system can be divided into four 3-phase regions. There are four binary compounds and four tie lines in the ZnO-WO3-B2O3 system. This system can be divided into five 3-phase regions. The possible component regions for ZnO single crystal flux growth were discussed. The phase diagram of Zn3B2O6-ZnWO4 pseudo-binary system has been constructed, and the result reveals this system is eutectic system. The eutectic temperature is 1007 degrees C and eutectic point component is 70 mol% Zn3B2O6. (c) 2007 Elsevier B.V. All rights reserved.

关键词: ZnO-MoO3-B2O3;ZnO-MoO3-WO3;ZnO-WO3-B2O3;Zn3B2O6-ZnWO4;phase relation;zno single-crystals;zinc oxide;growth;moo3-wo3

Gibbs Free Energy of Formation of 3Y_2O_3·5Al_2O_3

XU Xiuguang WANG Changzhen TU Ganfeng Northeast University of Technology , Shenyang , China.

材料科学技术（英文）

Thermodynamic properties of 3Y_2O_3·5Al_2O_3 double compound have been determined with CaF_2 single crystal electrolyte galvanic cell at 1049 K to 1230 K.The galvanic cell used can be expressed as: Pt,O_2(g)丨Y_2O_3(s),YOF_((s))丨CaF_2丨YOF_((s)), 3Y_2O_3·5Al_2O_(3(s))丨Al_2O_(3(s))丨O_2(g),Pt, of which the cell reaction is; 3Y_2O_(3(s))+SAl_2O_(3(s))=3Y_2O_3·SAl_2O_(3(s)) The following result is obtained: A_fG°(3Y_2O_3·5Al_2O_3)=-939500+765.90T±710J/mol where,△fG°(3Y_2O_3·5Al_2O_3)is the free energy of formation of 3Y_2O_3·5Al_2O_3 from Y_2O_3 and Al_2O_3.

关键词: rare earth , null , null

Synthesis, microstructure, and mechanical properties of Al(3)BC(3)

Journal of the American Ceramic Society

In situ synthesis of bulk Al(3)BC(3) was achieved via a reactive hot-pressing method using Al, B(4)C, and graphite powders at 1800 degrees C for 2 h. The reaction path for synthesizing Al(3)BC(3) was investigated. It was found that Al(3)BC(3) formed via the reaction of C, B(4)C, and Al(4)C(3) above 1180 degrees C. Dense Al(3)BC(3) was prepared with a little B(4)C and graphite remained. Microstructure observations revealed the plate-like morphology of Al(3)BC(3) grains. Moreover, the mechanical properties of Al(3)BC(3) were characterized (Vickers hardness of 11.1 GPa, bending strength of 185 MPa, fracture toughness of 2.3 MPa.m(1/2), and Young's modulus of 163 GPa). Young's modulus decreased slowly with increasing temperature, and at 1600 degrees C remained 79% of that at ambient temperature. These results show that Al(3)BC(3) is a promising lightweight high temperature structural material.

关键词: boron-carbide;high-temperature;youngs modulus;aluminum;al8b4c7;friction;ti3alc2;ti3sic2;composites;ceramics

Theoretical Explanations of the g Factors for Ni(3+) Ions in KMgF(3) and CsCaF(3) Crystals

Spectroscopy Letters

By using the optical spectral parameters of (NiF6)3- clusters in KMgF3:Ni3+ and CsCaF3:Ni3+ crystals estimated from the observed values in pure K3NiF6 crystal, the electron paramagnetic resonance (EPR) g factors for KMgF3:Ni3+ and CsCaF3:Ni3+ are calculated from the second-order perturbation formula (with the high-spin ground orbital state) based on the cluster approach. The results are in reasonable agreement with the observed values. The spin transition from the low-spin state in pure K3NiF6 crystal to the high-spin state in KMgF3:Ni3+ and CsCaF3:Ni3+ crystals owing to the slight increase of Ni3+ - F- distance is discussed.

关键词: crystal- and ligand-field theory;CsCaF3;electron paramagnetic;resonance;KMgF3;Ni3+;spin transition;spin-hamiltonian parameters;atomic screening constants;other-orbit;interactions;electronic spectra;scf functions;field;mgo;transition;distortion;complexes