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The purpose of this study is to evaluate the effectiveness of nanocontainer solutions in removing deteriorated and aged polymers commonly used in coating and consolidating archaeological glass.

This study focused on characterizing glass surfaces coated with two commonly used polymeric materials in archaeological glass preservation. Furthermore, the study evaluates the elimination of these coatings from the surfaces by using innovative aqueous systems composed of micellar solutions (MS) and oil-in-water (O/W) Texapon-P microemulsions (TEX). Glass samples coated with selected polymers were subjected to thermal and photochemical aging to simulate natural degradation conditions. This study aimed to evaluate the effectiveness of nanocontainer aqueous systems compared to acetone (Ac), a conventional solvent commonly used for removal procedures. The characterization procedures involved transmission electron microscopy, USB digital microscopy, scanning electron microscopy, color alteration and gravimetric measurement.

The findings indicate that the effectiveness of novel techniques using aqueous nanocontainer systems is quite promising when considering a “green approach” to preserving cultural heritage. Microscopic examination demonstrated the efficacy of MS in effectively removing acrylic and vinyl polymers from the glass surface. Furthermore, TEX proved effective in removing polyvinyl acetate (PVA) over Paraloid B72 (B-72). In addition, the measurement of color alteration values revealed a decrease after using MS compared to the standard sample before applying the polymers, with values of ΔE = 1.48 and 1.82 for B-72 polymer and PVA, respectively.

This research provides nanocontainer solutions for removing aged polymers from the glass surface. This makes the current study a promising step for treating archaeological glass.

This study aims to develop and test a model of the antecedents, mediators and consequences of the glass cliff phenomenon through public sector service organizations in Iran to explore more insights on gender inequality in managerial positions.

The current research was conducted based on a mixed-method approach, using both qualitative and quantitative research designs. First, the qualitative method includes content analysis by conducting semi-structured interviews with 20 university professors and expert managers working in public sector service organizations in Iran. The outcomes of the qualitative phase lead to designing the conceptual framework and research hypothesis. Then, through a quantitative phase, 384 female managers working in public sector service organizations in Iran are selected using stratified random sampling and fill out the research questionnaire. The exploratory factor analysis was used to verify the model. Moreover, structural equation modeling, using AMOS 24, was used to test the research hypothesis.

The findings of the qualitative phase were represented in three categories including antecedents (e.g. the characteristics of women’s leadership, the selection of women based on meritocracy criteria, women’s preferences and organizational factors), mediation effect (e.g. succession planning, personal development planning and support networks) and consequences of the glass cliff phenomenon (e.g. positive and negative consequences). The results of the exploratory factor analysis show there are ten components, explaining 88.5% of variances. Moreover, the test of the structural model supports the direct effect of antecedents on the glass cliff phenomenon. The results also show the effect of the glass cliff phenomenon on consequences through mediation effects.

There are some limitations that can be addressed by other researchers. Accordingly, the limited number of female managers in Iran prevented larger quantitative research. Moreover, the current research only found casual and mediation consequences of the glass cliff phenomenon, and potential moderators were not considered in this study.

The present study’s innovations may include using a mixed-method approach to investigate the antecedents, mediators and consequences of the glass cliff phenomenon in this study and examining the model constructs in some public sector service organizations. This research may provide a deep understanding of the antecedents, mediators and consequences of the glass cliff phenomenon by finding new factors using a mixed-method approach.

Non‐woven glass epoxy laminates are compared with paper phenolic and woven glass epoxy, indicating the advantages and limitations of the newer materials. Certain electrical properties are compared together with thermal and dimensional stability performances. This paper was presented at the Institute of Metal Finishing Printed Circuit Group Symposium “Circuits 77” in London during March 1977.

To study the degradation behaviour of borosilicate glass, which is suitable for hermetic sealing with Molybdenum and Kovar (Fe/Co/Ni) alloys, as a function of concentration and temperature in both acidic and alkaline media for long durations, up to 160 h.

The degradation (weight loss in mg/cm² of the glass sample) was determined by immersing the glass sample in HCl and NaOH solutions at different temperatures for different periods extending up to 300 h. The damage to the glass surface was seen under an optical microscope and the chemical species on the corroded surface were identified by electron spectroscopy for chemical analysis.

The borosilicate glass, having the nominal composition 0.70 SiO₂, 0.039 Na₂O, 0.028 K₂O, 0.21 B₂O₃, 0.01 Al₂O₃ was synthesized by melt and quench techniques. Degradation (corrosion) behaviour of this glass was investigated by immersing glass samples in 5 and 10 per cent HCl and 5 per cent NaOH solutions at different temperatures up to 90°C, for different periods and measuring dissolution rate (weight loss in mg/cm² of the sample). Dissolution rates were found to be 5.47 mg/cm² and 46.77 mg/cm² in 5 per cent NaOH at 60 and 90°C, respectively, whereas they were comparatively low (2.59 and 5.80 mg/cm² at 60 and 90°C, respectively, in 5 per cent HCl medium) after 160 h of total immersion period. The plot of dissolution rates against the temperatures showed the nonlinear behaviour at higher temperatures, probably due to the change in mechanism of corrosion. XPS studies exhibited the chemical species on the corroded surfaces. The optical microscopy of the corroded surface revealed that the corrosion mechanisms were different in acid and alkali media.

The degradation behaviour of borosilicate glass having a specific composition has been investigated as a function of concentration and temperature in both acid and alkaline media. The mixed alkali effect on the degradation behaviour may be studied by varying relative amount of Na₂O and K₂O in the glass composition.

The glass composition under the present study has been used for fabrication of matched type glass‐to‐metal (GM) seals with kovar alloy. In this respect the present study is significant in deciding the environmental conditions for its use.

The degradation behaviour of borosilicate glass having alkali and alkaline earth metal oxides has been investigated as a function of concentration and temperature in both acid and alkali media. The findings in this paper have the potential implications in deciding the environmental conditions for use of GM seals fabricated using this glass.

Examines the use of glass for glazing in buildings, concentrating on the four basic types: ordinary annealed glass; toughened glass, laminated glass and wired glass. Claims that, if the limitations of glass are understood, we have a wonderful, versatile, economic and durable material with as yet unexplored potential.

FOLLOWING extensive alterations to the aircraft‐glass department at the Kings Norton, Birmingham Factory of Triplex Safety Glass Company Limited, we were recently invited to witness the production of high‐strength glass panels for aircraft. The Triplex aircraft‐glass division, which was originally established to produce thick bullet‐proof glass for military aircraft during the last war, is now processing similar high‐strength glasses for such diverse uses as drive‐in banks, bullet‐proof vehicles, ships' bridges, diesel locomotives and, of course, military and civil aircraft clear vision panels. The Company at present supplies approximately 95 per cent of the aircraft glass used in this country, including panels for the V‐bombers, the VC.10, Trident, TSR.2, Buccaneer, Vanguard, Comet, Sea Vixen, Hunter and Viscount. Windscreens for the Bristol T.188 are also being produced.

The objective of the present work is to ascertain the failure modes under different loading speeds along with change in percentage of constituents of FRP composites.

This involves experimental investigation of FRP composites with woven roving fibers and matrix. Different types of composites, i.e. glass: epoxy, glass: polyester and (carbon+glass): epoxy are used in the investigation with change in percentage of constituents. The variability of fiber content of the composite is in the range of 0.55‐0.65 weight fractions. The matrix dominated property, like inter laminar shear strength (ILSS) has been studied by three point bend test using INSTRON 1195 material testing machine with increasing five cross head velocities.

The variation of ILSS of laminates of FRP composites is significant for low loading speed and is not so prominent for high speed. The variation of ILSS are observed to be dependent on the type and amount of constituents present in the composites. The laminates with carbon fiber shows higher ILSS than that of glass fiber composites. The laminates with epoxy matrix shows higher ILSS than polyester matrix composites for the same fiber. There is no significant variation of ILSS beyond loading speed 200 mm/min and this can be used for specifications of testing. Matrix resins such as polyester and epoxy are known to be highly rate sensitive. Carbon fiber are relatively rate independent and E‐glass fibers are rate sensitive. Woven roving carbon glass fiber reinforced polymer shows small rate dependence and woven roving glass fiber reinforced polymer shows significant rate sensitivity.

The findings are based on original experimental investigations in the laboratories of the institute and can be used for characterization of composites.

A developmental project has been initiated to create a new type of glass fabric, whose fibers are to be uniformly distributed in the laminate so as to comply with the requirement of homogeneity. As a result, various types of glass fiber fabrics have successfully woven through the uniquely developed “MS process”, and it has been verified that each of the glass fabrics possesses the most suitable structure to attain uniform distribution in the laminates. The laminates, using the newly developed glass fabrics, have proved that the micro‐diameter drilling, that is laser drilling and mechanical drilling with 0.1mm diameter, can be performed very easily with less drill bit breakage, and produces uniform drill holes. It has also been proved that the laminates with the new glass fabrics reveal improved mechanical properties such as lower CTE, decreased warp and twist and better dimensional stability compared with conventional laminates of glass epoxy. Various styles of new glass fabric cover the wide range of thickness from 100 microns down to 27 microns.

The mechanism of stress formation in glass under‐going conditions of rapid cooling, and the factors affecting the properties of the toughened glass produced are discussed. The application of techniques for measuring the temperature of glass, to the control and study of the toughening process are described.

The construction of windscreen panels for modern aircraft is described and the role of each component in meeting the requirements for pressure strength, bird resistance and optical performance is discussed. The influence of the physical properties of the windscreen components on the performance of complete laminated windscreens is discussed and the limitations imposed by these properties indicated. Silicone inter‐layers are beginning to replace polyvinyl butyral inter‐layers in high‐speed aircraft laminated transparencies when the temperatures reached are above the working limit of the conventional interlayers. New types of glass capable of withstanding prolonged exposure to higher temperatures than soda lime silica glass without loss of toughening stress, and also capable of withstanding more severe thermal shock without fracture, have been developed.