CaO—Al2O3—SiO2系统玻璃晶化时首析晶相及TiO2的作用机理预测和…

通过ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２系统玻璃的结构分析预测玻璃晶化时首析晶相是钙长石。选取ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２三元相图成玻璃区内的某点作为基础玻璃的组成，在基础玻璃吕加入ＴｉＯ２。用ＤＴＡ，ＸＲＤ和ＳＥＭ方法的研究结果表明，不玻璃中加ＴｉＯ２与否，晶化时首先析出的晶相都是钙长石，且均为从表面向内部生长，驰预测相符。     

中,高温钛乳浊釉显微结构的研究

应用ＸＲＤ、ＴＥＭ、ＳＡＤ及ＥＤＳ等测试技术，系统地研究了ＴｉＯ２及烧成温度对Ｋ２Ｏ－Ｎａ２Ｏ－ＣａＯ－ＭｇＯ－ＺｎＯ－Ａｌ２Ｏ３－ＳｉＯ２系瓷釉显微结构的作用。结果表明，在１１４０－１２２０℃烧 ，瓷釉中都存在分相与析晶现象，液滴相富含Ｔｉ＾４＋、Ｃａ＾２＋、Ｚｎ＾２＋而基体玻璃相富含Ｓｉ＾４＋，析出的晶体主要为钛榍石。随烧成温度的提高，析出晶体的数量不断减少。另外，当ＴｉＯ２加入量增加时瓷釉的     

中,高温钛乳浊釉显微结构的研究

应用ＸＲＤ、ＴＥＭ、ＳＡＤ及ＥＤＳ等测试技术，系统地研究了ＴｉＯ２及烧成温度对Ｋ２Ｏ－Ｎａ２Ｏ－ＣａＯ－ＭｇＯ－ＺｎＯ－Ａｌ２Ｏ３－ＳｉＯ２系瓷釉显微结构的作用。结果表明，在１１８０℃—１２２０℃烧成时，瓷釉中都存在分相与析晶现象，液滴相富含Ｔｉ４＋、Ｃａ２＋、Ｚｎ２＋，而基体玻璃相富含Ｓｉ４＋，析出的晶体主要为钛榍石。随烧成温度的提高，析出晶体的数量不断减少。另外，当ＴｉＯ２加入量增加时瓷釉的分相程度、液滴数量及尺寸将随之增大。     

CaO-Al_2O_3-SiO_2系统玻璃晶化时首析晶相及TiO_2的作用机理预测和研究

通过ＣａＯＡｌ２Ｏ３ＳｉＯ２系统玻璃的结构分析预测玻璃晶化时首析晶相是钙长石。选取ＣａＯＡｌ２Ｏ３ＳｉＯ２三元相图成玻璃区内的某点作为基础玻璃的组成，在基础玻璃中加入ＴｉＯ２。用ＤＴＡ，ＸＲＤ和ＳＥＭ方法的研究结果表明，不管玻璃中加ＴｉＯ２与否，晶化时首先析出的晶相都是钙长石，且均为从表面向内部生长，与预测相符。ＴｉＯ２作为晶核剂，效果不太明显，在高温时ＴｉＯ２只能使玻璃网络结构松弛，粘度降低，促进玻璃中晶相的成核和生长。     

CeO2对CaO—MgO—Fe2O3—Al2O3—SiO2系玻璃晶化的影响

本文阐述了制备以ＣｅＯ２为晶核剂的ＣａＯ－ＭｇＯ－Ｆｅ２Ｏ３－Ａｌ２Ｏ３－ＳｉＯ２系微晶玻璃,采用ＳＥＭ,ＸＲＤ和ＤＴＡ等技术,研究了ＣｅＯ２对玻璃成核与晶化的影响,确定了析出的晶相,讨论了加入ＣｅＯ２后玻璃析晶活化能的变化,结果表明,ＣｅＯ２的加入能降低玻璃晶化活化能,促进玻璃相分离使制得的微晶玻璃强度增大,但析出的主晶相仍为钙铁辉石。     

TiO2对堇青石基微晶玻璃的分相与晶化的影响

采用Ｘ射线衍射分析、透射电镜、扫描电镜差热分析等测试技术、研究了ＴｉＯ２在ＭｇＯ－Ａｌ２Ｏ３－ＳｉＯ２系堇青石基玻璃晶化过程中的作用。发现ＴｉＯ２的加入,改变了系统析出初晶相的类型,降低了析晶活化能,促进了玻璃的整体折晶。而且ＴｉＯ２的引入,还有利于玻璃的分相,进一步促进了系统的核化和晶倾无ＴｉＯ２引入的情况下,同一组成的ＭｇＯ－Ａｌ２Ｏ３－ＳｉＯ２系玻璃为表面析晶。     

Na2O—Al2O3—B2O3—SiO2系统溶胶,凝胶涂层的振动光谱研究

本文用振动光谱分析了Ｎａ２Ｏ－Ａｌ２Ｏ３－Ｂ２Ｏ３－ＳｉＯ２系统溶胶中的化学反应和用浸渍法制备的凝胶涂层结构。结果表明：部分硼、铝在溶胶陈化初期就与Ｓｉ（ＯＣ２Ｈ５）４的水解或缩聚产物反应形成线性聚合物，宜于浸涂。热处理时涂层中继续形成Ｓｉ－Ｏ－Ｓｉ、Ｓｉ－Ｏ－Ａｌ和Ｓｉ－Ｏ－Ｂ键；基本结构单元为［ＳｉＯ４］、［ＢＯ４］、［ＢＯ３］和［ＡｌＯ４］。     

复合晶核剂（MoO3＋CaF2）对铝硅酸盐玻璃析晶行为的影响作用研究

采用ＤＴＡ，ＳＥＭ，ＥＤＡＸ，ＳＡＤＰ和ＸＲＤ等测试方法研究了含复合晶核剂（ＭｏＯ３＋ＣａＦ２）的铝硅酸盐玻璃的分相与析晶行为。实验结果表明，含单一晶核剂ＣａＦ２或ＭｏＯ３的玻璃仪产生表面析晶，而ＣａＦ２和ＭｏＯ３共同引入时能诱导玻璃的体内核化，ＣａＦ２和ＭｏＯ３均能降低基玻璃的析晶温度，整体析晶的机理是ＣａＦ２促进了玻璃的分相，ＭｏＯ３富集子分相玻璃的富钙相中，热处理过程中优先析出了ＣａＭｏＯ４     

国外期刊陶瓷文摘

国外期刊陶瓷文摘含不同填料的耐磨玻璃陶瓷复合材料［俄］／ＨＭ等／／ＣＴＥｐａ－１９９５，（３）．－１４～１５对含不同填料─—工业氧化物（Ａｌ２Ｏ３，ＺｒＯ２，Ｃｒ２Ｏ３）的ＣａＯ—ＢａＯ—Ａｌ２Ｏ３－ＴｉＯ２－ＳｉＯ２系硅微晶玻璃基复合材料的物理机械...     

Na2O和K2O对CaO—Al2O3—SiO2—R2O—ZnO红色微晶玻璃若干性能的影响

研究了碱金属Ｎａ２Ｏ和Ｋ２Ｏ对ＣａＯ－Ａｌ２Ｏ３－ＳｉＯ２－Ｒ２Ｏ－ＺｎＯ红色微晶玻璃着色及烧结和折晶的影响及作用,以及微晶玻璃烧结和析晶随热处理温度变化的规律。     

多卤代吡啶选择性合成醚类的反应

以KOH为碱,DMSO为溶剂,在空气中,温度为50℃的条件下,多卤代吡啶和苯酚类化合物反应,形成相应的醚类化合物,该反应具有很好的收率以及区域选择性,是一种有效构建C-O键的方法;以K_2CO_3为碱,DMSO和H_2O为溶剂,在空气中,室温下,多卤代吡啶和苯硫酚类化合物反应,形成相应的的吡啶硫醚化合物,该反应也具有很好的收率以及区域选择性,是一种有效构建C-S键的方法。     

Electronic Structure and Properties of the O2+2, SO2+ and S2+2 Diatomic Dications

Multiply charged ions show novel energetic features which can potentially have useful photophysical properties. In order to investigate these interesting type systems, energy interaction curves for the ground and excited electronic states of O²⁺₂, SO²⁺, and S²⁺₂ have been generated by the ab initio complete active space multiconfiguration self-consistent field (CAS-MCSCF) method. The calculations were carried out in a triple-zeta sp plus double-zeta d Gaussian function basis set using compact effective potentials to replace the core electrons. In order to gauge the accuracy of the results, analogous calculations were carried out on the valence isoelectronic N₂ and NO⁺ systems for which experimental information is available for comparison of geometric and spectroscopic properties. Diverse high energy spectroscopy experiments on O²⁺₂ are interpreted and reconciled using the calculated ground and excited state energy interaction curves. Special attention is paid to the ₃Σ₊^u state, whose location and character have been particularly puzzling. Almost all the dication molecular states studied show the characteristic avoided crossing of diabatic states which gives a trapped equilibrium structure and a barrier to dissociation. These features make the dication kinetically stable, but thermodynamically unstable with an exothermic dissociation energy. The spectroscopy experiments on O²⁺₂ show that these states are experimentally attainable.     

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。     

Separation and purification of aflatoxins B1, B2, G1 and G2, and comparison of semi-synthetic aflatoxins B2 and G2 with naturally-occurring aflatoxins B2 and G2

A method is described for the isolation of highly purified aflatoxins B₁, B₂, G₁ and G₂ from extracts ofAspergillus flavus. The four aflatoxins, isolated from background impurities by rapid passage of the extracts through an acid alumina column, are separated from each other by chromatography on a silica gel column. Aflatoxins B₂ and G₂ are prepared by hydrogenation of the mixture of aflatoxins B₁, B₂, G₁ and G₂ and then separated by elution from a silica gel column with chloroform containing 0.7% ethanol. A comparison of semi-synthetic aflatoxins B₂ and G₂ with naturally-occurring aflatoxins B₂ and G₂ shows no significant difference in physical properties. Presented at the AOCS-AACC Meeting, Washington, D.C. April, 1968.     

Melting and dilatometric behavior of 2-Oleopalmitostearin and 2-Oleodistearin

The glycerides, 2-oleopalmitostearin and 2-oleodistearin, which are important components of confectionery fats, were synthesized, and their melting behavior and dilatometric properties were determined. Each glyceride was found to have four melting points: 18.2, 24.5, 33.0, and 37.4°C, for 2-oleopalmitostearin; 22.8, 30.0, 37.7, and 42.8°C, for 2-oleodistearin. The rate of transformation of the thermodynamically unstable polymorphs at temperatures just below their melting points was found to vary from a few seconds to more than eight days. For each glyceride, expansivities were determined for three polymorphs and melting dilations for two polymorphs. Mixtures of the two glycerides were examined dilatometrically and found to behave in some respects as single components. The mixtures were readily tempered so that both components were in the same polymorphic form, and expansivities and melting dilations were obtained for mixtures in three polymorphic forms. Dilatometric data also were obtained for a sample of cocoa butter and a sample of sweet milk chocolate of the coating type. Presented at the 32nd Fall Meeting, American Oil Chemists’ Society, Chicago, Ill., October 20–22, 1958. Fellow, National Confectioners’ Association. One of the laboratories of the Southern Utilization Research and Development Division, Agricultural Research Service, U. S. Department of Agriculture.     

纳米TiO2和微米SiO2改性及分散性能的研究

采用不同的分散工艺和改性剂对纳米TiO2和微米SiO2粉体进行处理,使用激光粒度仪、红外光谱(IR)、热失重(TG)等手段对粉体粒径,粉体表面结构进行表征,探讨了超微粉体在乙二醇(EG)中分散的最佳工艺.结果表明:钛酸酯偶联剂(NDZ-201)可在纳米TiO2表面接枝,接枝率约为6%;硅烷偶联剂(KH570)可在微米S...     

Thermal Expansion of HfO2 and ZrO2

The thermal expansion of a low symmetry crystal can be much more interesting than the lattice parameter expansion would suggest. Here, the complete thermal expansion tensors for monoclinic and tetragonal phases of ZrO₂ and HfO₂ have been measured in air, by high‐resolution, high‐temperature X‐ray diffraction. These results reveal the highly anisotropic nature of thermal expansion in the monoclinic phase as well as a cooperative movement of ions and the existence of a zero thermal expansion plane.     

氢氧直接合成法制过氧化氢技术进展

氢气和氧气直接合成过氧化氢是典型的原子经济性反应，因过程简单、产品清洁、生产成本低而成为催化领域研究开发的一个热点。总结了该法近年来在催化剂活性组分的选取及载体方面的进展；详细介绍了溶剂的选取和反应机理；讨论了各种反应器的安全性。指出今后的研究重点是提高氢气利用率、开发新型的反应器、提高过程的安全性。     

Eu~(2+)掺杂SrSi_2O_2N_2和Sr_(0.37)Ba_(0.60)Si_2O_2N_2荧光粉的发光性能及应用

采用高温固相法合成Sr_(0.97)Eu_(0.03)Si_2O_2N_2和Sr_(0.37)Ba_(0.60)Eu_(0.03)Si_2O_2N_2荧光粉,通过X射线衍射、激发光谱、发射光谱及转换后LED器件的性能等研究了荧光粉的结构、发光性能和稳定性。结果表明:在稀土Eu2+掺杂的Sr Si2O2N2荧光粉中,当部分Sr2+被Ba2+取代后,形成三斜晶系的Sr_(0.37)Ba_(0.60)Eu_(0.03)Si_2O_2N_2荧光粉,激发和发射光谱红移,在近紫外-蓝光区具有更高的激发效率。将2种荧光粉与Ga(N)In芯片封装,Sr0.37Ba0.60Eu0.03Si2O2N2荧光粉转换的白光LED器件,在光效、显色指数和光效维持特性方面均高于Sr_(0.97)Eu_(0.03)Si_2O_2N_2转换的LED器件。     

三氟乙醇的生产和应用前景

介绍了三氟乙醇的性质，生产方法和应用前景。