Improvement of the chemical composition and founding technology of high-lead glass in a high-efficiency furnace

1995 ◽  
Vol 52 (8) ◽  
pp. 199-202
Author(s):  
A. P. Sivko ◽  
V. V. Lityushkin ◽  
V. I. Uvarov ◽  
A. I. Zyuzin ◽  
M. V. Yakovleva
1998 ◽  
Vol 22 (1) ◽  
pp. 12-16
Author(s):  
Gerhard Eggert
Keyword(s):  

2009 ◽  
Vol 5 (H15) ◽  
pp. 331-343
Author(s):  
K.N. Nagendra ◽  
P. Bonifacio ◽  
H.-G. Ludwig

Much of what we know about the chemical composition of the Universe actually stems from the chemical composition of stars, which is often deciphered from the spectra emerging from their atmospheres. Cool, low-mass and long-living stars allow to study the evolution of the Universe's chemistry from a time shortly after the big bang until today. The observation and interpretation of stellar spectra is a classical field in astronomy but is still undergoing vivid developments. The enormous increase in available computational resources opened-up possibilities which led to a revolution in the degree of realism to which modelers can mimic Nature. High-resolution, high-stability, high-efficiency spectrographs are now routinely providing stellar spectra whose full information content can only be exploited if a very much refined description of a stellar atmosphere is at hand.


1994 ◽  
Vol 9 (9) ◽  
pp. 2304-2313 ◽  
Author(s):  
M. Prudenziati ◽  
B. Morten ◽  
P. Savigni ◽  
G. Guizzetti

Seven batches of a high-lead glass were used for the preparation of RuO2-based thick film resistors. Investigation of their electrical properties showed a lack of reproducibility of results whose origin was related to changes of the physicochemical properties of the glassy matrix. A systematic investigation of the glass batches, both in form of frit powders and screen printed and fired layers, was carried out with several spectroscopies to detect changes in composition and structure. The spectroscopic methods included x-ray Energy Dispersive Fluorescence (EDS), Scanning Electron Microscopy (SEM), Atomic Absorption (AA), diffuse optical reflection of the powders and specular reflection of the layers, optical transmission, and other complementary methods. The dissolution of Al, due to interaction between the glasses and the alumina substrate, as well as the diffusivity and solubility of Ag due to interaction with the Ag-bearing terminations were measured. The results demonstrated that, apart from small compositional differences, the various batches were characterized by differences in residual stresses, redox reactions, and “microstructure.” The latter was responsible for very notable differences in the optical properties of the glasses, which in turn are closely related with the difference in atomic solubility and diffusivity. Optical spectroscopies have been found to be a suitable means for testing reproducible preparation methods of glass frits for thick-film hybrid microelectronics.


2000 ◽  
Vol 321-324 ◽  
pp. 1051-1055
Author(s):  
B. Fortin ◽  
A.F. Gualtieri ◽  
Matteo Leoni ◽  
M. Prudenziati ◽  
C.C. Tang

Author(s):  
V.A. Ushkov ◽  
O.L. Figovsky

In the present work we have studied the thermal stability, flammability, fume evolution of epoxy matrix composites with different types and amounts of hardeners, fillers, plasticizers and fire retardants. It is shown that chemical composition of fillers has little effect on the flammability of epoxy composites when the content of mineral fillers is less than 45% by mass. Smoke formation decreases linearly with increasing the degree of filling. It is shown that to obtain low-combustible materials the oxygen index should exceed 31%. It was found that the optimal concentration of industrial brominated fire retardants is 8-10% by mass. To reduce the flammability of epoxy composites, additive brominated fire retardants in the form of a solution in N,N-dimethyl-2,4,6-tribromoaniline have been proposed. The high efficiency of acetyl-and α-hydroxyethyl ferrocene as a smoke suppressor of epoxy composites is shown.


Author(s):  
A. I. Zaitsev

The task of principal (multiple) increase of complex of service parameters (often being hard compatible) and steel quality under conditions of costs decrease becomes more and more actual. The solution is possible by creation and application of new principles and approaches based, first of all, on adequate physical and chemical predicting methods and effective technological skill of control non-metallic inclusions, forms of impurities, phase isolations, structure state, including homogeneity of the metal volume. A complex approach to prediction, analysis of phase composition, structure state and steel properties elaborated to implement this progressive direction. It has an important feature like elaborated in details scientific principles. The principles allow not only to make effective the development of new steel and technologies of their production at minimum costs, but also to reveal the content, directions and intensity of processes having place during metal processing. It was illustrated at the example of microalloyed (stabilized) by titanium super-high-carbon IF steel. Importance of accounting of regularity of phase isolations forming kinetics shown, that can result in considerable change of their characteristics and steel properties. This circumstance can be used for unification of chemical composition or development of cassette technologies production, for example, from IF-steels of the same chemical composition, of rolled products of different assortment or strength class. It was shown, that the complex phase isolations forming takes place with participation impurities and elements presented in the steel. Therefore there arose wide possibilities of considerable increase of complex of properties at decreasing of costs. Presence of deformation considerably accelerates the processes of nano-size phase isolations forming not only during rolling, but also during parts manufacturing by hot stamping, combined with steel quenching. This allows to increase their strength by 300–400 MPa additionally to martensitic structure. It is possible, apart from principal perfection of parameters of service characteristics stability, to reach considerable increase of composition homogeneity, structure and properties in the whole metal volume by non-metallic inclusions forming control. Forming of silicate glassy inclusions in low-alloyed steels improves principally the macro- and microstructure of CC billet and impact toughness of rolled products KCV–40 (420–445 J/сm2 ). Their presence in the steel stipulated by kinetic reasons. Additional substantial increase of composition homogeneity, structure and microalloyed steels properties can be reached during the rolling process by return redistribution of components from the axis zone to the surface of the rolled product. High efficiency of the above-mentioned approaches at present has been confirmed by development an array of pipe, structural, automobile steels and highly efficient technologies of their production.


2021 ◽  
pp. 1-20
Author(s):  
Elena Salinas ◽  
Jorge De Juan ◽  
Juan M. Piñero ◽  
M. Teresa Casal ◽  
Nadine Schibille ◽  
...  

It has long been assumed that lead glazing technology preceded glassmaking in the Western world and that the technological transfer was from glazes to glass. Here, we present new evidence for the reverse, the indigenous innovation of glassmaking and its transfer to glazes in early Islamic al-Andalus (Spain). Compositional analyses show that Islamic lead glazes from Córdoba are intimately related to a distinct type of high-lead glass, suggesting a connection between the two technologies. The archaeological remains from a pottery workshop indicate that the glazing process initially involved the production of a lead glass and is not linked to earlier Roman or other contemporary glazing technologies. The data also demonstrate that the potters not only used the same materials and techniques but borrowed stylistic and decorative models from glassmaking.


Author(s):  
Bernardo Farfan ◽  
William Reinhart ◽  
Scott Alexander

Abstract Equation of state properties were studied for the high-lead glass Corning 0120, which is a potash-soda-lead glass also referred to as G12. This glass, which contains approximately 30% PbO by weight and has a density, ρo, of 3.034 g/cm3 possesses properties suitable for many applications in industry such as optical components for space exploration instrumentation. Further understanding of its mechanical properties is desired for more complex applications in various fields, including applications where the glass may experience high-pressure shock loading. In this work plate impact experiments were conducted to determine the dynamic response of Corning 0120 at high stress levels. Tests were conducted over the pressure range from approximately 5 to 24 GPa utilizing the 90 mm bore single-stage powder driven gas gun at the Sandia National Laboratories STAR Facility. For this study, we used one-inch diameter Corning 0120 glass samples of two different thicknesses (3 mm and 7 mm) to use the evolution of the shock wave propagation through the material for analysis. The time-resolved material response was measured by means of a Velocity Interferometer System for Any Reflector system (VISAR). Results will be presented detailing the high-pressure shock loading response characteristics of the high-lead glass Corning 0120. Comparisons are made with similar results for lead free glass to assess the most prominent changes compared to lower density glasses and other lead filled glasses.


2001 ◽  
Vol 3 (7) ◽  
pp. 667-674 ◽  
Author(s):  
M Prudenziati ◽  
B Morten ◽  
B Forti ◽  
A.F Gualtieri ◽  
G Mihai Dilliway
Keyword(s):  

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