n(B2O3)/n(SiO2)对硼硅酸盐玻璃结构和性能的影响

采用热膨胀仪、扫描电镜和红外光谱仪研究了硼硅酸盐玻璃的结构与性能随n(B2O3)/n(SiO2)和n(B2O3)/n(Na2O)的变化规律,深入探讨了结构对分相、热膨胀系数和膨胀软化温度的影响规律。结果表明:热膨胀系数取决于玻璃中[BO3]、[BO4]和[SiO4]的数量变化;玻璃的转变温度和软化温度主要由SiO2决定;[BO3]对玻璃的分相有着重要的影响;不论n(B2O3)/n(Na2O)比值多少,玻璃结构中均存在[BO3]和被破坏的[SiO4]。     

n（SiO2）／n（B2O3）比对无公害熔剂性能的影响

以碱一硼一硅系统为研究体系,探讨了n(SiO2)/n(B2O3)比对无公害熔剂光泽度、耐蚀性、膨胀系数等性能的影响规律。用高温显微镜、热膨胀仪、光泽度仪、显微硬度仪测试了不同硼硅比的无公害熔剂的主要性能,分析了其性能变化的原因。实验结果表明,n(SiO2)/n(B2O3)为1.6～2.0时,熔剂的各种性能与彩烤效果较好。     

MgO/(CaO+MgO)对碱硼硅酸盐系统低温熔剂耐磨性的影响

通过调整MgO/(CaO+MgO)摩尔比(简写为:RMg),探讨了混合碱土金属效应对ABS无铅低温熔剂的耐磨性及相关的光泽度、光泽损失、维氏硬度、热膨胀系数等性能的影响规律;对样品进行了 XRD、FTIR、SEM及热膨胀分析,从结构上阐释了其性能变化的原因.结果表明:在ABS熔剂结构中存在[SiO4]、[BO4]、[B...     

无碱铝硼硅系玻璃结构的红外光谱

用熔融退火方法制备无碱SiO2-B2O3-A12O3-RO(R=Mg,Ca,Sr,Ba)系玻璃.玻璃的成分范围以摩尔计为:SiO2,64.17%～70%;B2O3,7%～14.12%;Al2O3,9.88%～16.94%;RO总量,12%(2.4%MgO,4.8?O,2.4%SrO,2.4?O).用Fourier变换红外光谱研究了上述玻璃系统结构随成分的变化规律,同时,对玻璃结构与热膨胀系数、密度等物理性质的关系也进行了研究.结果表明:在Al含量较高的铝硼硅系玻璃中,B更多的以[BO3]形态存在.随着SiO2和B2O3摩尔比的增大,[BO3]的量有所减少,而热膨胀系数呈增加趋势,密度出现极大值.随着Al2O3和B2O3摩尔比的增大,[BO3]的量出现极值,热膨胀系数也出现极值,密度总体趋势是增加的.铝硼硅系玻璃的热膨胀系数、密度等物理性质与玻璃结构密切相关.     

组分对(K,Na)2O-CaO-Al2O3-B2O3-SiO2系分相乳浊釉性能的影响

采用正交试验法探究组分对(K,Na)2 O-CaO-Al2 O3-B2 O3-SiO2系分相乳浊釉性能的影响,结果表明,(K,Na)2 O/CaO、Al2 O3的变化致使釉的熔融温度和表面张力发生改变,对釉面光泽度影响较大,而Al2 O3、SiO2含量的变化主要改变Al、Si在釉中的配位多面体状态以及Si对游离氧的争夺,因此对釉面乳浊白度有较大影响.(K,Na)2 O/CaO值的变化影响了釉中网络改性剂的含量,B2 O3摩尔含量的变化影响了釉中[BO3]、[BO4]的相对含量,因此两者改变了釉玻璃的结构致密程度进而影响釉面硬度.最优条件下制得釉样白度高于正交试验所有试样,釉式为0.5mol(K,Na)2 O-0.5molCaO-0.4molAl2 O3-0.4molB2 O3-6molSiO2,全熔块制备工艺条件下,釉样白度为58.2％,光泽度为89.3％,维式硬度为669.33 HV,釉面针孔缺陷得到显著改善.     

Al2O3对硼硅酸盐玻璃热膨胀和分相的影响

通过红外光谱分析了Al2O3取代SiO2后硼硅酸盐玻璃结构的变化,测试了玻璃的热膨胀系数和膨胀软化温度,通过扫描电子显微镜分析硼硅酸盐玻璃的分相,并结合X射线能谱分析了富硅相的组成.结果表明:硼硅酸盐玻璃中引入Al2O3后,随着Al2O3取代量的增加,玻璃结构中[BO3]增多,[BO4]减少;玻璃的热膨胀系数增大,转变温度和软化温度提高;硼硅酸盐玻璃中引入Al2O3后对玻璃的分相没有明显的改善作用.     

Na2O含量对日用玻璃贴花装饰用无铅熔剂性能的影响

以R2O-ZnO-B2O3-SiO2(ZBS)体系为日用玻璃贴花装饰用无铅熔剂的基础配方,通过调整Na2O的含量,探讨Na2O含量对熔剂性能的影响。采用热膨胀仪、光泽度仪、SEM及FT-IR对样品的热膨胀系数、光泽度及显微结构进行表征,分析熔剂组成-结构-性能之间的关系和变化规律。结果表明:样品的热膨胀系数α随Na2O的增加先增大后减小;光泽度、耐碱性随Na2O的增加而增大;耐酸性、彩烤温度随Na2O的增加而降低。当w(Na2O)=9.07%时,ZBS系统熔剂的α与玻璃基板的匹配性最好,光泽度能达到82,耐酸性最好,耐碱性甚至可以达到商业标准的4～5级。     

Al2 O3对硼硅酸盐玻璃结构和性能的影响

硼硅酸盐玻璃具有优良的抗热冲击性能和优异的光学性能。主要探讨了Al2 O3对硼硅酸盐玻璃的结构和性能的影响。通过红外光谱测试分析了Al2 O3含量不同时玻璃的结构变化,测试了玻璃的热膨胀系数,转变温度、膨胀软化温度、粘度和化学稳定性。研究结果表明：Al2 O3的加入使得玻璃结构中[ BO4]减少,[ BO3]相应增加,从而使得玻璃结构疏松。玻璃的热膨胀系数增大,Tg 和膨胀软化点Td 降低,化学稳定性减弱;但玻璃的软化点Tf 在Al2 O3含量小于3%时,随Al2 O3含量增加有降低趋势,大于3%时随Al2 O3含量增加有增大的趋势。玻璃的高温粘度随Al2 O3的加入增大,但低温粘度减小。     

ZrO2对中硼硅医药玻璃结构与性能的影响

采用熔融冷却法制备中硼硅医药玻璃,以ZrO2等质量替代Al2O3.通过红外光谱分析玻璃结构,测试玻璃密度、热膨胀系数、高温粘度以及化学稳定性.研究结果表明:随着ZrO2替代Al2O3质量增加,玻璃结构中[BO3]增多,[BO4]减少,密度逐渐增加,玻璃的热膨胀系数先增大后减小;高温粘度呈现先降低后增大趋势,ZrO2增加对玻璃颗粒耐水和耐酸性能影响不大,而对玻璃颗粒耐碱性能有显著提升作用.     

P2O5对Bi2O3-B2O3-ZnO体系玻璃结构及热性能的影响

采用传统的熔融冷却的方法制备了(40-x)Bi2O3-30B2O3-30ZnO-xP2O5(0≤x≤15mo1％)体系玻璃.使用红外光谱、拉曼光谱、DSC和热膨胀仪研究了封接玻璃的结构和热性能.红外光谱及拉曼光谱结果表明,P2O5作为网络形成体,以[PO4]进入到玻璃的网络结构中,玻璃的网络结构性增强.玻璃结构中[BO3]三角体结构单元相对含量有增多趋势,[BO4]四面体、[BiO3]三角体、[BiO6]八面体结构单元相对含量减少.随着P2 O5含量的增加,玻璃化转变温度和玻璃的初始析晶温度升高;玻璃的密度减小.Bi2O3-B2O3-ZnO-P2O5体系封接玻璃热膨胀系数减小,从8.289×10-6℃-1减小到6.354×10-6℃-1.玻璃的软化点逐渐增大,从416℃升高到524℃.     

减少H2O2干扰测定稳定性ClO2含量的方法

用碘量法测定稳定性ClO2溶液中的ClO2含量时,当稳定液中过碳酸盐过量,测定结果会偏高.作者提出将待测样酸化后加入稍过量的K2Cr2O7与其中的H2O2反应以消除其影响,再用碘量法测定的新方法.方法操作简便,结果可靠,为较准确地检测含过量过碳酸盐的稳定性ClO2溶液中的ClO2真实含量提供了新的途径.     

生产乙炔对电石的要求及乙炔清净

目前国内外乙炔大部分仍是由电石制得。然而由于工业电石除CaC2 外还含有很多杂质 ,所以生产乙炔不仅要求电石的纯度、粒度 ,还要求水温。一般电石的块度采用 8～ 2 5mm ,发生器温度控制在 85± 5℃ ,乙炔气体中含H2 S、H3 P、NH3 等气体会使氯乙烯合成氯化催化剂活性下降。因此 ,必须对乙炔气体进行清洁。采用次氯酸钠液体的氧化性将乙炔中的杂质氧化成酸性物质而除去。     

Combustion of the Ti-Zr-N2-H2 composition

Combustion ofTi andZr powders in nitrogen(10–70 atm) with subsequent burn-up of the produced -alloys in hydrogen and alsoTi-Zr powder combustion in anN ₂+H₂ mixture have been studied. The optimal conditions for producing monophase nitrogen-containing alloys and monophase hydronitrides with high hydrogen concentration have been found. The effect of the second metal(Zr) on the combustion regularities, on an increase in the hydrogen solubility in -alloys, and on the thermal stability of the hydronitrides produced has been elucidated. Hydrogen is shown to behave as a homogenizer in combustion of the above compositions.Translated from Fizika Goreniya i Vzryva, Vol. 32, No. 6, pp. 62–67, November–December 1996.     

Na-Ti-Si氧化物Ti元素的化学状态分析

利用熔融方法制备了Na2O-TiO2-SiO2系统玻璃样品，用IR以及XPS等测试手段对系统玻璃样品结构进行了分析。结果表明：Na2O-SiO2-SiO2系统玻璃中Ti^4 离子可以部分地取代Si^4 离子的位置而以网络形成体的形式参与成玻。此外，通过对该系统玻璃的XPS钛元素的化学状态分析，认为该系统玻璃中Ti^4 离子存在[TiO4],[TiO6]等几种不同的微结构单元，并且随着玻璃中TiO2含量的增加，该系统玻璃中四方双锥结构的[TiO6]与正四面体结构的[TiO4]之比增大。     

On the structure of glass of the PbO-B2O3-SiO2 and CdO-SiO2-B2O3 systems

Using the method of X-ray scattering at large angles, the structure of single-phase glass of the PbO-B₂O₃-SiO₂ and CdO-B₂O₃-SiO₂ systems has been studied. The glass of the two-component PbO-B₂O₃ and PbO-SiO₂ systems of the three-component PbO-B₂O₃-SiO₂ system, containing from 10 to 60 mol % of SiO₂ at equal fractions of B₂O₃ and PbO, and the glass of a number of compositions of the CdO-B₂O₃-SiO₂ system containing from 30 to 60% of CdO are investigated. A change in the prevailing interatomic spacings in the dependence on the glass composition is determined. The boron-oxygen network provides the orderliness in the distribution of ions-modifiers observed at distances on the order of 6 Å. It is found that in contrast to boron-oxygen network, the silicon-oxygen network does not have the ability to order the distribution of the ions-modifiers.     

Effect of ZrO2 nanocrystals on the stabilization of the amorphous state of alumina and silica in the ZrO2-Al2O3 and ZrO2-SiO2 systems

Structural and chemical transformations in the ZrO₂-Al₂O₃ and ZrO₂-SiO₂ systems containing ZrO₂ nanocrystals are examined. It is shown that the presence of zirconia nanoparticles in the oxide mixture retards the processes of crystallization and phase formation. The revealed effect is explained by the space blocking of nucleation in the systems under consideration.     

Comparison of the reactivities of 2-mercaptoaniline and 2-hydroxyaniline with 2-chloronicotinoyl chloride

The reaction between equimolar 2-chloronicotinoyl chloride and 2-mercaptopyridine in ClCH₂CH₂Cl, after 30 minutes refluxing in ClCH₂CH₂Cl solution, produced pyrido[2,3,b][1,5]benzothiazepin-5(H)one 7, and 6-[3-(2-benzothiazolyl)pyridin-2-yl)thio]-N-[3-(2-benzothiazolyl)pyridin-2-yl]aniline 8. In contrast, the reaction using the same reaction conditions between equimolar 2-chloronico- tinoyl chloride and 2-hydroxypyridine, produced the simple amide, 2-chloro-N-(2-hydroxyphenyl) nicotinamide 9. 2-Chloro-N-(2-mercaptophenyl)nicotinamide was considered to be a common intermediate in the formation of 7 and 8. The characterizations of 7–9 were achieved by X-ray crystallography. The conformations of 7 and 8 in the solid state can be described as “U” and “V”-shaped, respectively.     

A coupled phase diagram experimental study and thermodynamic optimization of the Li2O-CaO-Al2O3 and Li2O-CaO-SiO2 systems,and prediction of the phase diagrams of the Li2O-CaO-Al2O3-SiO2 system

A coupled experimental phase diagram study and thermodynamic modeling of the Li₂O-CaO-Al₂O₃ and Li₂O-CaO-SiO₂ systems was conducted at 1 atm total pressure. Differential scanning calorimetry (DSC) measurements were performed in the Li₂O-CaO-Al₂O₃ and Li₂O-CaO-SiO₂ systems. In addition, the phase relations in the Li₂O-CaO-Al₂O₃ system were determined by equilibration/quenching experiments at 1643 and 1743 K, and the phases were characterized with X-ray diffraction (XRD) and Electron-probe micro analysis-wavelength dispersive spectroscopy (EPMA-WDS). The absence of ternary compounds or solid solutions was confirmed. Congruent melting of Li₂CaSiO₄ compound in the Li₂O-CaO-SiO₂ system was determined at 1350 ± 5 K. Thermodynamic optimization of the Li₂O-CaO-Al₂O₃ and Li₂O-CaO-SiO₂ systems was carried out based on new phase diagram experiments and critically evaluated literature data. The phase diagrams of the quaternary Li₂O-CaO-Al₂O₃-SiO₂ system were predicted using the thermodynamic models with optimized model parameters.     

SiO2-TiO2-Al2O3-R2O系统逆性玻璃中TiO2耐碱二重性的探讨

通过测定SiO2-TiO2-Al2O3-R2O系统逆性玻璃的耐碱性及由玻璃转入碱侵蚀液中的SiO2及TiO2的量,分析了TiO2在玻璃耐碱性上的二重性,得出氧化物自身的耐碱性与氧化物对玻璃耐碱性的影响是2个不同的概念.