Al2O3和P2O5共同掺杂的SiO2玻璃的溶胶-凝胶法制备及其光学性质研究

以磷酸三乙酯、硝酸铝和正硅酸乙酯为原料，采用溶胶－凝胶法成功地制备了掺杂有Ａｌ２Ｏ３和Ｐ２Ｏ５的ＳｉＯ２玻璃。通过热分析和表面分析研究了凝胶向玻璃的转化过程，解释了热处理过程中的碳化现象，确定了热处理的适宜温度和时间。研究了掺杂有Ａｌ２Ｏ３和Ｐ２Ｏ５的ＳｉＯ２玻璃的光学性质。     

Cul微晶掺杂硅凝胶玻璃及其薄膜的制备与光谱性质

采用溶胶－凝胶工艺制成ＣｕＩ微晶掺杂硅凝胶玻璃及其薄膜。通过Ｘ射线粉末衍射（ＸＲＤ）和高分辨透射电镜（ＨＲＴＥＭ）分析观察到玻璃中的晶相及其分布；由薄膜的室温透射光谱发现，随着热处理温度提高和时间延长，薄膜的特征透射谱谷向长波方向移动（红移），并源于玻璃中的量子尺寸效应。     

Controlling ion release from bioactive glass foam scaffolds with antibacterial properties

Bioactive glass scaffolds have been produced, which meet many of the criteria for an ideal scaffold for bone tissue engineering applications, by foaming sol-gel derived bioactive glasses. The scaffolds have a hierarchical pore structure that is very similar to that of cancellous bone. The degradation products of bioactive glasses have been found to stimulate the genes in osteoblasts. This effect has been found to be dose dependent. The addition of silver ions to bioactive glasses has also been investigated to produce glasses with bactericidal properties. This paper discusses how changes in the hierarchical pore structure affect the dissolution of the glass and therefore its bioactivity and rate of ion delivery and demonstrates that silver containing bioactive glass foam scaffolds can be synthesised. It was found that the rate of release of Si and Ca ions was more rapid for pore structures with a larger modal pore diameter, although the effect of tailoring the textural porosity on the rate of ion release was more pronounced. Bioactive glass scaffolds, containing 2 mol% silver, released silver ions at a rate that was similar to that which has previously been found to be bactericidal but not high enough to be cytotoxic to bone cells.     

CuI微晶掺杂硅凝胶玻璃及其薄膜的制备与光谱性质

抄采用溶胶-凝胶工艺制成Cul微晶掺杂硅凝胶玻璃及其薄膜。通过X射线粉末衍射（XRD）和高分辨透射电镜（HRTEM）分析观察到玻璃中的晶相及其分布；由薄膜的室温透射光谱发现，随着热处理温度提高和时间延长，薄膜的特征透射谱谷向长彼方向移动（红移），并源于玻璃中的量子尺寸效应。     

Sol-gel processing of materials for electronic and related applications

Various techniques of sol-gel processing for the preparation of electronic and related materials are described and reviewed. Typical examples are chosen from thin films and coatings of gels, crystalline materials and glasses as also bulk glasses to illustrate the variations in processing parameters and material properties.     

Preparation of glass by sintering

Preparation of glass articles by sintering of glass and amorphous powders is considered. The classification of sintering processes includes: (a) sintering of premelted and pulverized glasses; (b) sintering of premelted chemically treated glasses; (c) sintering without melting; (d) sintering with melting. The most interesting class of processes is sintering without, or simultaneously with, melting and it includes preparation of preforms for optical fibres and the sol-gel route for glass preparation. This last route is reviewed in detail. Two main versions are considered: preparation of gels by hydrolysis and polymerization of alkoxides, and sintering of amorphous colloidal powder compacts. The sol-gel processes represent an embryo of a new technology for the production of high-melting glasses (including quartz glass) at relatively low temperatures.     

碘化亚铜微晶掺杂硼硅酸盐玻璃的制备及其电致二阶非线性光学效应

采用可分相的Na2－Al2O3－B2O3－SiO2系为基础玻璃，以CuO／SnO、NaI为原料；分别引入Cu 、I－，成功地制备出CuI微晶掺杂硼硅酸盐玻璃·通过X射线粉末衍射（XRD）和高分辨透射电镜（HRTEM）分析观察到了玻璃中的晶相及其分布；由玻璃的室温透射光谱研究了玻璃的热处理条件与光吸收性的关系．首次报道了该半导体微晶掺杂玻璃中的电致二次谐波发生，并讨论了该效应的机理．     

The use of advanced diffraction methods in the study of the structure of a bioactive calcia: silica sol-gel glass

Sol-gel derived calcium silicate glasses may be useful for the regeneration of damaged bone. The mechanism of bioactivity is as yet only partially understood but has been strongly linked to calcium dissolution from the glass matrix. In addition to the usual laboratory-based characterisation methods, we have used neutron diffraction with isotopic substitution to gain new insights into the nature of the atomic-scale calcium environment in bioactive sol-gel glasses, and have also used high energy X-ray total diffraction to probe the nature of the processes initiated when bioactive glass is immersed in vitro in simulated body fluid. The data obtained point to a complex calcium environment in which calcium is loosely bound within the glass network and may therefore be regarded as facile. Complex multi-stage dissolution and mineral growth phases were observed as a function of reaction time between 1 min and 30 days, leading eventually, via octacalcium phosphate, to the formation of a disordered hydroxyapatite (HA) layer on the glass surface. This methodology provides insight into the structure of key sites in these materials and key stages involved in their reactions, and thereby more generally into the behaviour of bone-regenerative materials that may facilitate improvements in tissue engineering applications.     

含Zn、Mg生物玻璃的制备及性能研究

采用溶胶-凝胶法,在58S生物玻璃的基础上,分别用0.5wt％的氧化镁和氧化锌取代氧化钙制备了含镁和含锌的生物玻璃.压制的试样分别在600、700和800℃煅烧以做强度测试,并分析了600和800℃煅烧后的物相组成.结果表明,三种试样煅烧至800℃仍为玻璃态,而镁锌的掺入大幅度提高了生物玻璃的强度,这主要是因为Mg-O和Zn-O具有比Ca-O高的键能.模拟体液浸泡试验表明,镁和锌降低了羟基磷灰石的早期成核速度,但并不影响其后期的生长.浸泡三天后所有样品表面都被羟基磷灰石覆盖,表明了样品具有良好的生物活性.     

Antibacterial and bioactive silver-containing Na2O·CaO·2SiO2 glass prepared by sol–gel method

The antibacterial effect of addition of silver oxide to Na2O x CaO x 2SiO2 glass have been studied. Silver containing and silver free Na2O x CaO x 2SiO2 glasses have been prepared by sol-gel synthesis using tetramethil orthosilicate, sodium ethoxide, calcium nitrate tetrahydrate and silver nitrate as starting materials and methyl ethyl ketone as solvent. The gel was examined by differential thermal analysis, thermo gravimetric analysis, FTIR spectroscopy and X-ray diffraction analysis. Antibacterial and bioactive tests on gel glass powders, obtained after a heat treatment of 2 h at 600 degrees C of the dried gel, were carried out. High antimicrobial effects of samples against Escherichia coli and Streptococcus mutans were found. FTIR measurements and SEM micrographs have ascertained the formation of a hydroxyapatite layer on the surface of samples soaked in a simulated body fluid for different times.     

Effect of calcination temperature on the luminescent properties of Tb-doped borosilicate glasses

The luminescent properties of Tb³⁺ have been studied for borosilicate glasses prepared by a sol-gel method. Gel bodies were formed from solutions consisting of silicon tetraethoxide, triethyl borate, ethanol, water and terbium nitrate, then sintered into a bulk glass. The Tb³⁺ luminescence in glasses mostly shows green light under UV excitation, because the emission line at 545 nm occupies the main part of the energy emitted. The observed luminescence consisted of four main emission lines originating from the ⁵D₄ level. However, a remarkable spectral change has been observed for the Tb³⁺ luminescence in borosilicate glasses after firing at about 800°C. This spectral change due to heat treatment was found to be large enough to show yellow or red luminescence, suggesting that the crystal field acting on Tb³⁺ is very strong. The spectral energy distribution of Tb³⁺ luminescence in sol-gel derived borosilicate glasses were investigated in relation to the effects of calcination temperature.     

溶胶-凝胶法制备生物微晶玻璃的研究进展

溶胶-凝胶法是一种材料合成新工艺,现已广泛用作生物植入体、组织工程支架及药物载体的生物活性玻璃粉体、块体玻璃、多孔生物微晶玻璃与涂层的制备.简要介绍了溶胺-凝胶法制备生物微晶玻璃的工艺原理和优缺点,着重分析了其研究和应用现状,并阐述了其发展前景.     

SiO2凝胶玻璃中Eu^＋,Tb^3＋与1,10—邻菲罗啉配合物的原位化学？…

应用原位化学复合方法，将Ｅｕ＾３＋、Ｔｂ＾３＋与，１，１０－邻菲罗啉配合光学均匀复合到ＳｉＯ２凝胶玻璃中，解决了国稀土含氮配合物易水解而难以用溶胶－凝胶工艺将其均匀掺入无机基质的问题。研究了原位配合物的荧光和热学性能。结果表明，由于配合物的形成使稀土离子特征荧光强度显著增加，而无机基质的保护作用则使原位配合物热稳性提高２００℃以上。化学合成纯配合物Ｅｕ（Ｐｈｅｎ）２Ｃｌ３·２Ｈ２Ｏ的高分辨荧光谱表     

碘化亚铜微晶掺杂硼硅酸盐玻璃的制备及其电致二阶非线性光学效应

采用可分相的Ｎａ２－Ａｌ２Ｏ３－Ｂ２Ｏ３－ＳｉＯ２系为基础玻璃，以ＣｕＯ／ＳｎＯ、ＮａＩ为原料，分别引入Ｃｕ＾＋、Ｉ＾－，成功地制备出ＣｕＩ微晶掺杂硼硅酸盐玻璃。通过Ｘ射线粉末衍射（ＸＲＤ）和高分辨透射电镜（ＨＲＴＥＭ）分析观察到了玻璃中的晶相及其分布；由玻璃的室温透射光谱研究了玻璃的热处理条件下光吸收性的关系。首次报道了该半导体微昌掺杂玻璃中的电致二次谱波发生，并讨论了该效应的机理。     

Antireflective coatings based on SiO<Subscript>2</Subscript> nanoparticles

Single-layer antireflective coatings, produced by sol-gel method on soda-lime glass substrates, were studied. Optimal parameters of the silica sols synthesis and coating procedure of the antireflective coatings based on SiO₂ nanoparticles on soda-lime glasses for producing composite glasses with high optical transmittance within the visible range of wavelengths were obtained.     

Sol-gel synthesis of luminescent InP nanocrystals embedded in silica glasses

III-V semiconductor nanocrystals rarely exist as spherical inclusions inside glasses, due to difficulties during their preparation, such as high toxic reagents or fast oxidation under usual glass technology temperatures. In this letter a sol-gel method for synthesis of InP nanocrystals embedded in silica glasses was described. Gels were synthesized by hydrolysis of a complex solution of Si(OC2H5)4, InCl3.4H2O, and PO(OC2H5)3. Then, the gels were heated at 600 degrees C in the presence of H2 gas to form fine cubic InP crystallites. Raman spectrum showed an InP longitudinal-optic mode (342 cm(-1)) and a transverse-optic mode (303 cm(-1)). The size of InP nanocrystals was found to be from 2 to 8 nm in diameter by transmission electron microscopy. A strong photoluminescence with a peak at 856 nm was observed from InP nanocrystals embedded in silica glasses. The results suggest that it might be possible to synthesize other III-V semiconductor nanocrystals embedded in silica glasses through the sol-gel process.     

Optical behaviour of tetracyanoplatinate (MCP) encapsulated sol-gel glasses

The photoluminescence spectra at atmospheric pressure and high pressure photoluminescence spectra of the tetracyanoplatinate salts (MCP) KLiCP·2H₂O, KNaCP·3H₂O, Cs₂Ca(CP)₂·nH₂O and Cs₂CP·H₂O encapsulated sol-gel glasses are reported. In all these sol-gel glass systems we have found large pressure dependent shift of the photoluminescence maxima under hydrostatic high pressure condition (up to 13 nm/kbar) and therefore, prove to be as most sensitive probes to enable us to calculate pressure at different stages of gelation, aging and drying of the gel glass. The pressure dependent shift, along with the position of the peak maxima and band width at half height, are measured for the photoluminescence spectra at atmospheric pressure as well as at high pressure. Concentration effect has also been studied in the present system to arrive at more conclusive picture of the dopant matrix and dopant-dopant interaction. The fluorescence life time, as well as integrated emission intensity as a function of concentration, have also been studied in all the four glass systems which allows us to identify the dimer and cluster spectra.     

Glass formation in the system PbO-PbCl2

The preparation of glasses in the system PbO-PbCl₂ is described. The behaviour of the glass transition temperatures, heat capacities and microhardnesses as a function of glass composition has been investigated. The variations are discussed in terms of the structural features of the glasses.Communication No. 256 from the Solid State and Structure Chemistry Unit.     

Effect of addition of chloride on the crystallization behaviour of fluoride glasses in ZrF4-BaF2-CsF system

Fluoride glasses based on ZrF₄-BaF₂-CsF doped with BaCl₂ up to 10 mol% have been prepared. Crystallization behaviour of these glasses has been investigated by means of DTA and XRD. Addition of 5 mol% BaCl₂ into the fluoride glass of the ZrF₄-BaF₂-CsF system enhances the glass forming ability and the thermal stability against crystallization, but the glass forming ability is decreased for glass containing 10 mol % of BaCl₂. The results have been discussed from the view point of thermodynamics and the dynamics of glass formation.     

Sintering and microstructure development of glass-bonded silver thick films

The sintering of glass-bonded silver thick films has been studied by dilatometry and microscopic analysis. Effects of particulate characteristics of silver and glass frit powders, glass composition, silver/glass ratio, and substrate materials have been discussed. It is shown that the silver-glass interaction is one of the most important factors responsible for the microstructure. Most of all, glasses promoted the densification of the thick film. Microstructure development has been understood by the stage of sintering as determined by the combined effects of temperature and silver/glass ratio.