Über Glasbildung und Eigenschaften von Chalkogenidsystemen. XIX. Zur Glasbildung von HgSe mit Germaniumseleniden

Glass Formation and Properties of Chalcogenide Systems. XIX. Glass Formation of HgSe with Germanium Selenides Glass formation is found in the System HgSe? GeSe? GeSe₂ in a large range of composition. The dependence of properties such as glass transition temperature, mole volume, mole polarization, and electrical conductivity on composition suggests a remarkably lower modifier function of HgSe on the germanium selenide glasses in comparison to PbSe. Two regions which are characterized by different structural units in the glass can be deduced from the curves. Annealing results in the formation of the new compound Hg₂ GeSe₃ as well as of two phases which could not be identified up to now. In special limits of composition HgSe/GeSe melts form glasses, too.     

Influence of Al2O3 and P2O5 contents in sol-gel ionomer glass system on the structure and their cement properties

Journal of Sol-Gel Science and Technology - Glass ionomer dental cement (GIC) is commonly used as a restorative material. The sol-gel synthesis of the ionomer glass is an alternative method, which...     

Properties and application of graphite fluoride, (C2F)n

Graphite fluoride is classified into (CF)_n and (C₂F)_n types from the structure and composition. (CF)_n has been already synthesized industrially in fairly large quantities and utilized as an excellent cathodic depolarizer in lithium organic electrolyte batteries. Furthermore, many researches on the application have been carried out in comprehensive industrial fields such as lubricant, water repellent, mold release agent, etc.On the other hand, a new type of graphite fluoride, (C₂F)_n, is also expected as the promising new material in a wide variety of industrial fields. However, it had been not produced to date on an industrial scale.Central Glass Co., Ltd. has further developed the industrial technology for mass production of (C₂F)_n and has been brought it to the stage of plant construction, in addition to (CF)_n.In this paper, the properties and the applications of (C₂F)_n will be reported in comparison with those of (CF)_n.     

Gas chromatographic analysis of estrogens from pregnant mares' urine using glass capillary columns

Glass capillary columns coated with OV-225 and Silar 10C were used to analyze estrogens (as their trimethylsilyl derivatives) present in pregnant mares' urine. Such columns provide better resolution in a shorter time than the corresponding packed columns, as exemplified by the separation of estrone from equilin.     

Coated microsphere as spherical cavity Raman laser

Glass spheres of high refractive index n _D = 1.93 were coated with hybrid film of n _D = 1.49 by the sol-gel technique for Raman lasers. Glass spheres dispersed in acetone solvent with silicone oligomer were sprayed by an air-spray equipment on a Teflon sheet. On the sheet terrace-shaped coated spheres were obtained. Stimulated Raman emission of WGM was demonstrated by pumping terrace portion of the coated spheres with Ar⁺ laser (514.5 nm wavelength).     

Evidence for the change of inner-sphere hydration number of rare earth ions in the middle of the series

Glass transition temperatures of aqueous solutions of rare earth chlorides and perchlorates have been measured. The anomalous T_g change in the middle of the senes is interpreted as evidence for the coordination number change of rare earth ions, in accordance with the views expressed by Spedding et al. in 1966.     

Quelques caracteristiques morphologiques de melanges de polymeres a base de propene et de butene

This paper reports a study of the morphology of blends of polypropene with polybutene as a function of composition. Techniques such as differential thermal analysis, thermomechanical analysis and dilatometry were used. The “compatibility” of these polyolefines is considered. Glass transition temperatures of the homopolymers are detectable when using the various techniques.     

Glass Wool Catalysed Regioselective Isomerization of Styrene Oxides

Glass wool is widely used as an insulating material. Here we report for the first time, the function of glass wool as a mild heterogeneous catalyst under vapor phase conditions — particularly for the rearrangement of styrene oxides including halogen‐substituted styrene oxides to the corresponding phenyl acetaldehydes. Using this methodology, 4‐isobutyl‐α‐methyl styrene oxide is smoothly converted to 4‐isobutyl‐α‐methyl phenyl acetaldehyde which is the precursor of the API “Ibuprofen” — an important pharmaceutical agent.     

NMR Wool Tube: a novel method for NMR solution analysis of derivatized glass surfaces

Glass wool was placed within an NMR tube as a solid support for the covalent attachment of a molecule to allow for a simple one-dimensional 1H FT NMR solution analysis. This novel procedure avoids the use of expensive sample tubes or platforms, as required for magic angle or fast spinning, exotic pulse sequences, isotopic labeling or the use of a large number of scans to provide the ability to analyze the structure, mobility, ligand binding, and solvent interactions of the surface bound molecule.     

Affinity Chromatography-Based Assays for the Screening of Potential Ligands Selective for G-Quadruplex Structures

DNA G-quadruplexes (G4s) are key structures for the development of targeted anticancer therapies. In this context, ligands selectively interacting with G4s can represent valuable anticancer drugs. Aiming at speeding up the identification of G4-targeting synthetic or natural compounds, we developed an affinity chromatography-based assay, named G-quadruplex on Oligo Affinity Support (G4-OAS), by synthesizing G4-forming sequences on commercially available polystyrene OAS. Then, due to unspecific binding of several hydrophobic ligands on nude OAS, we moved to Controlled Pore Glass (CPG). We thus conceived an ad hoc functionalized, universal support on which both the on-support elongation and deprotection of the G4-forming oligonucleotides can be performed, along with the successive affinity chromatography-based assay, renamed as G-quadruplex on Controlled Pore Glass (G4-CPG) assay. Here we describe these assays and their applications to the screening of several libraries of chemically different putative G4 ligands. Finally, ongoing studies and outlook of our G4-CPG assay are reported.     

Sequential Injection System with Modified Glass Capillary for Automation in Immunoassay of Chondroitin Sulfate

Sequential injection was introduced to perform a multi-step immunoassay. Modified low cost hematocrit glass capillary was employed as the immobilization surface for a competitive immunoassay of chondroitin sulfate (CS), a potential biomarker for cancer. Glass capillary is low cost and adapts well to the flow system without causing back pressure. The analysis time per sample run with automation of the multi-step immunoassay is improved as compared to the conventional batch-wise micro-plate format. The performance of the sequential injection capillary immunoassay (SI-CI) system for CS was evaluated with spiked human serum samples.     

Direct analysis of glass powder samples by radio frequency glow discharge atomic emission spectrometry (rf-GD-AES)

A method is described for the elemental analysis of glass powder samples by rf-GD-AES. Glass powder samples were pressed without binder to form sample disks. A brass sample holder was designed to hold the pellet onto the source and provide a good vacuum seal. Sample preparation conditions and particle sizes are shown to influence spectral characteristics and plasma stabilization times. The discharge operating parameters were optimized based on both raw analyte signal intensity (S) and signal-to-background ratio (S/B), the latter was found more useful in terms of sample-to-sample precision and quantification. A NIST Standard Reference Material (SRM 89 Lead-Barium Glass) was used to evaluate the method. The limits of detection for trace components ranged from 1–10 g/g for several elements, depending on the concentrations of the analytes in the SRM. Sample-to-sample reproducibilities were better than 10% RSD and linear calibration curves were obtained using either the Si (I) optical emission as an internal standard or the individual analyte's S/B characteristics.     

Neue Entwicklungen in der Glaschemie

Glass, although known for thousands years, has been heavily investigated in the past few years. This was mainly caused by the demand on advanced materials for optics and optoelectronics. Here, active laser glasses and glasses for laser optics especially for the deep W-range played an important part. Other important developments were glass fibres for various wavelengths and optoelectronic devices, such as waveguides. Additionally, new glass ceramics have focused a great deal of interest. Besides those glass ceramics possessing extremely low thermal expansion, glass ceramics for biomedical applications, e.g. as material for human bone replacement as well as oriented glassceramics have intensively been studied.     

玻璃成分分析标准物质的研究及应用

玻璃标准物质是用于比较的基准物质,在玻璃的生产和质量控制中是保证数值有效可靠的基础.分析了国内外玻璃标准物质的研究进展情况,论述了玻璃标准物质的作用,同时指出了现阶段玻璃标准物质研究中存在的问题,并指出了其未来的发展方向.     

Radiation‐grafted solid polymer electrolyte membrane: thermal and mechanical properties of sulfonated fluorinated ethylene propylene copolymer (FEP)‐graft‐acrylic acid membranes

Acrylic acid was grafted onto fluorinated ethylene propylene copolymer (FEP) using a simultaneous radiation technique and the resulting membranes were subsequently sulfonated. Thermal and mechanical properties of these membranes were investigated and were found to be strongly influenced by the degree of grafting. Thermogravimetric analysis (TGA) of these membranes showed that these membranes undergo multistep degradation unlike virgin FEP which degrades in a single step. Glass transition temperature and degree of crystallinity were determined by differential scanning calorimetry (DSC). Glass transition temperature increased while crystallinity decreased with increase in degree of grafting. Tensile strength and elongation at break were found to decrease on grafting and further on sulfonation. Copyright © 2004 John Wiley & Sons, Ltd.     

Glass transition temperature and stress relaxation of methanol equilibrated poly(methyl methacrylate)

Glass transition temperatures are reported for narrow MWD PMMA for a range of MW, where the polymer is (a) free of methanol, and (b) equilibrated with methanol. The relationship between the glass transition temperature and MW is discussed in terms of current empirical and thermodynamic theories.     

Identification and Classification of Iridescent Glass Artifacts with XRF and SEM/EDX

 Art Nouveau (Tiffany, Loetz) and modern (Jack Ink, Strini Art Glass) iridescent glass fragments were characterized using energy dispersive X-ray fluorescence analysis (EDXRF) and energy dispersive X-ray microanalysis in a scanning electron microscope (SEM/EDX) in combination with factor analysis in order to obtain clustring. A character istic of Tiffany glass fragments is leaded bulk glass, whereas in the case of Loetz K-Ca-Si bulk glass could be determined. Modern glass fragments show a high amount of Na (7 wt% in the bulk of Jack Ink) and 0.6–1.5 wt% Sr in the bulk of Strini Art Glass. The contents of Si and Ca are similar to Loetz glass. Furthermore, the differences in the structure of the glass artifacts could be determined. The cross-sections of Tiffany show a layered structure of the bulk without a specific surface layer whereas the cross-sections of Loetz glass reveal a homogeneous bulk material with one or two homogeneous surface layers in the BE-image. In the case of the Jack Ink a homogeneous bulk glass and an inhomogeneous multilayered surface could be determined. Strini Art Glass show a homogeneous bulk glass and a homogeneous surface layer in the backscattered electron image.     

Untersuchungen an elektronenleitenden Oxidsystemen. I. Zur Glasbildung im System K2O-SiO2-VO2

Investigations on Electronically Conducting Oxide Systems. I. Glass Formation in the System K₂O? SiO₂? VO₂ Glass formation in the system K₂O-SiO₂-VO₂ was investigated. The glass forming region is compared with the glass formation in the system K₂O-SiO₂-TiO₂. Density and electrical conductivity of the glasses are discussed in denpendence on the composition.     

Analysis of polar compounds on PEG-40M/KF glass capillary columns

The chromatographic properties of potassium fluoride as an additive to the polyethylene glycol stationary phase were investigated. This unique base in organic chemistry was shown to succeed in yielding good results for the analysis of polar compounds, including the primary amines. Glass capillary columns of high selectivity for primary and secondary aliphatic amines were obtained by the “hexane plug” procedure by which a thin layer of KF is deposited on the inner surface of glass capillary columns. Some possible types of donor-acceptor interactions occuring within the system PEG/KF/solute were considered.     

Effects of post-treatment on crystallization behavior of glass fiber-reinforced polyamide 66 composite with red phosphorus flame retardant

Journal of Thermal Analysis and Calorimetry - Glass fiber-reinforced polyamide 66 composite with red phosphorus flame retardant (PA66-GF FR (RP)) has excellent strength and flame retardant...