Effect of P2O5 Impurities and Fluoride Ions on The Rheological Properties of Porous Glasses and Bismuth-Containing Composites Based on Them

Abstract The results of a study of the rheological properties (shrinkage on heating, viscosity) of porous glasses (PGs) obtained as a result of through acid leaching of two-phase sodium borosilicate glass doped with small additives of P2O5 and fluoride ions, as well as bismuth-containing PGs and quartzoid glasses based on them, depending on the temperature of the heat treatment of the PG and in comparison with the characteristics of the samples obtained from sodium borosilicate glass without additives, are presented. It is found that doping glass with the indicated impurities leads to a decrease in the thermal resistance of the obtained PGs and bismuth-containing PGs. The introduction of bismuth nitrate into PG in the case of the low-temperature treatment (at 120°C) lowers the temperature for the same viscosity values of quartzoid glasses by 15–20°C, in contrast to samples without additives, as well as from higher-temperature treatment (at 650°C) PGs with additives.

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Direct Observation of the Phase Separated Microstructure of a Sodium Borosilicate Glass and Its Development During Heat Treatment

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097168 ◽

1981 ◽

Vol 39 ◽

pp. 90-91

Author(s):

D. Imeson ◽

J. B. Vander Sande

Keyword(s):

Heat Treatment ◽

Borosilicate Glass ◽

Mechanical Grinding ◽

Sodium Borosilicate Glass ◽

Two Phase ◽

Immiscibility Region ◽

Corning Glass ◽

Chemical Etch ◽

Carbon Coated ◽

Full Investigation

By treating Corning code 7740 sodium borosilicate glass (composition by weight 80.5% SiO2, 13% B2O3, 3.8% Na2O, 2.2% Al2O3, 0.4% K2O) with a process consisting of heat treatment within the immiscibility region followed by a chemical etch, it is possible to produce a thin surface layer on the glass giving a low total optical reflectivity over the entire visual spectrum. In the course of a full investigation into this phenomenon, an attempt has been made to fully characterize the nature and development of the two-phase structure produced by the heat treatment.Coupons of glass 3 x 3 x 0.125 inches, as received from Corning Glass Works, were heated for times ranging between 1-1/2 and 1000 hours at 600°C (well below the phase transition temperature, about 650°C for this glass). It is known that a three-hour heat treatment maximizes the antireflective property. Electron microscope specimens were conventionally prepared by mechanical grinding and ion thinning. However, after ion thinning, specimens were chemically etched by floating them on a drop of 0.1 wt% NH4.HF in 1.6N HNO3 solution, for typically 2 to 5 minutes. Specimens were rinsed by repeated flushing with distilled water, dried, and then carbon coated to prevent charging effects.

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Features of the anomalous scattering of light in two-phase sodium borosilicate glass

Journal of Optical Technology ◽

10.1364/jot.80.000706 ◽

2013 ◽

Vol 80 (11) ◽

pp. 706 ◽

Cited By ~ 7

Author(s):

M. P. Shepilov ◽

O. S. Dymshits ◽

A. A. Zhilin ◽

A. E. Kalmykov ◽

G. A. Sycheva

Keyword(s):

Borosilicate Glass ◽

Anomalous Scattering ◽

Sodium Borosilicate Glass ◽

Two Phase ◽

Scattering Of Light

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Optical properties of sodium-borosilicate glass fibres

Electronics Letters ◽

10.1049/el:19740357 ◽

1974 ◽

Vol 10 (22) ◽

pp. 450 ◽

Cited By ~ 5

Author(s):

C.R. Day ◽

J.E. Midwinter ◽

G.R. Newns ◽

R.W.J. Uffen ◽

R. Worthington

Keyword(s):

Optical Properties ◽

Borosilicate Glass ◽

Sodium Borosilicate Glass ◽

Glass Fibres

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The Influence of Ocean Acidification and Warming on DMSP & DMS in New Zealand Coastal Water

Atmosphere ◽

10.3390/atmos12020181 ◽

2021 ◽

Vol 12 (2) ◽

pp. 181

Author(s):

Alexia D. Saint-Macary ◽

Neill Barr ◽

Evelyn Armstrong ◽

Karl Safi ◽

Andrew Marriner ◽

...

Keyword(s):

Ocean Acidification ◽

Coastal Water ◽

Phytoplankton Community ◽

Dimethyl Sulfide ◽

Temperature Treatment ◽

Low Ph ◽

Trace Gas ◽

Mesocosm Experiments ◽

Future Warming ◽

Higher Temperature

The cycling of the trace gas dimethyl sulfide (DMS) and its precursor dimethylsulfoniopropionate (DMSP) may be affected by future ocean acidification and warming. DMSP and DMS concentrations were monitored over 20-days in four mesocosm experiments in which the temperature and pH of coastal water were manipulated to projected values for the year 2100 and 2150. This had no effect on DMSP in the two-initial nutrient-depleted experiments; however, in the two nutrient-amended experiments, warmer temperature combined with lower pH had a more significant effect on DMSP & DMS concentrations than lower pH alone. Overall, this indicates that future warming may have greater influence on DMS production than ocean acidification. The observed reduction in DMSP at warmer temperatures was associated with changes in phytoplankton community and in particular with small flagellate biomass. A small decrease in DMS concentration was measured in the treatments relative to other studies, from −2% in the nutrient-amended low pH treatment to −16% in the year 2150 pH and temperature conditions. Temporal variation was also observed with DMS concentration increasing earlier in the higher temperature treatment. Nutrient availability and community composition should be considered in models of future DMS.

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Effect of copper incorporation on phase transformation behavior of electroless nickel–phosphorous coating and its effect on the tribological behavior

Proceedings of the Institution of Mechanical Engineers Part L Journal of Materials Design and Applications ◽

10.1177/1464420720981602 ◽

2020 ◽

pp. 146442072098160

Author(s):

Abhijit Biswas ◽

Suman Kalyan Das ◽

Prasanta Sahoo

Keyword(s):

Heat Treatment ◽

Phase Transformation ◽

Tribological Behavior ◽

Electroless Nickel ◽

Two Phase ◽

Microstructural Changes ◽

Treatment Conditions ◽

Heat Treated ◽

Higher Temperature ◽

Effect Of Copper

The microstructural changes of electroless Ni–P–Cu coating at various heat-treatment conditions are investigated to understand its implications on the tribological behavior of the coating. Coatings are heat-treated at temperatures ranging between 200°C and 800 °C and for 1–4 h duration. Ni–P–Cu coatings exhibit two-phase transformations in the temperature range of 350–450 °C and the resulting microstructural changes are found to significantly affect their thermal stability and tribological attributes. Hardness of the coating doubles when heat-treated at 452 °C, due to the formation of harder Ni3P phase and crystalline NiCu. Better friction and wear performance are also noted upon heat treatment of the coating at the phase transformation regime, particularly at 400 °C. Wear mechanism is characterized by a mixed adhesive cum abrasive wear phenomena. Heat treatment at higher temperature (600 °C and above) and longer duration (4 h) results in grain coarsening phenomenon, which negatively influences the hardness and tribological characteristics of the coating. Besides, diffusion of iron from the ferrous substrate as well as greater oxide formation are noticed when the coating is heat-treated at higher temperatures and for longer durations (4 h).

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First Principles Calculations of Stress-Induced Structural Changes of Supercooled Borosilicate Glass

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.725.399 ◽

2016 ◽

Vol 725 ◽

pp. 399-404

Author(s):

Kausala Mylvaganam ◽

Wei Dong Liu ◽

Liang Chi Zhang

Keyword(s):

Uniaxial Compression ◽

Borosilicate Glass ◽

Structural Changes ◽

Mass Density ◽

Glass Network ◽

Borosilicate Glasses ◽

First Principles Calculations ◽

Sodium Borosilicate Glass ◽

Compression Direction ◽

Network Form

Unlike the traditional silicate glasses, borosilicate glasses behave differently because of the addition of boron atoms. Extensive studies have been carried out to understand the abnormal function of boron in glass network. However, it is not clear how the atomic structure of borosilicate glass changes under loading. This paper investigates the behaviour of borosilicate glass under uniaxial compression with the aid of ab initio simulations. Sodium borosilicate glass having 160 atoms and a mass density of 2.51 g/cm3 with composition 3Na2O-B2O3-6SiO2 were equilibrated first at 3500K, then at 2500K, 1500K, 1200K, 1000K, 825K and 625K. Structural analysis showed that at higher temperatures the sodium borosilicate liquid does not have a specific structure. At around 825 K (i.e. around Tg), boron network and silicon network form and remain stable even at a temperature of 625 K. When the supercooled sample at 825K was subjected to uniaxial compression, the stress along the compression direction first increases and then decreases with a change in boron structure, which could modify the behaviour of the borosilicate glass.

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