Thermal, structural and optical behaviour of Eu3+ ions in Zinc Alumino Boro-Silicate glasses for bright red emissions

2021 ◽  
pp. 124787
Author(s):  
M. Monisha ◽  
M.S. Murari ◽  
M.I. Sayyed ◽  
Hanan Al-Ghamdi ◽  
Aljawhara H. Almuqrin ◽  
...  
Keyword(s):  
Silicate Glasses ◽  
Optical Behaviour

Direct observations of radiation-enhanced transformations in glass

1983 ◽  
Vol 41 ◽  
pp. 354-355
Author(s):  
J. F. DeNatale ◽  
D. G. Howitt
Keyword(s):  
Glass Matrix ◽  
Diffusion Mechanism ◽  
Bubble Formation ◽  
Silicate Glasses ◽  
Phase Decomposition ◽  
Direct Observations ◽  
Thin Foils ◽  
Oxygen Bubble ◽  
Electron Energy Loss ◽  
Kinetics Of

The electron irradiation of silicate glasses containing metal cations produces various types of phase separation and decomposition which includes oxygen bubble formation at intermediate temperatures figure I. The kinetics of bubble formation are too rapid to be accounted for by oxygen diffusion but the behavior is consistent with a cation diffusion mechanism if the amount of oxygen in the bubble is not significantly different from that in the same volume of silicate glass. The formation of oxygen bubbles is often accompanied by precipitation of crystalline phases and/or amorphous phase decomposition in the regions between the bubbles and the detection of differences in oxygen concentration between the bubble and matrix by electron energy loss spectroscopy cannot be discerned (figure 2) even when the bubble occupies the majority of the foil depth.The oxygen bubbles are stable, even in the thin foils, months after irradiation and if van der Waals behavior of the interior gas is assumed an oxygen pressure of about 4000 atmospheres must be sustained for a 100 bubble if the surface tension with the glass matrix is to balance against it at intermediate temperatures.

Coloration of Ce-doped Multicomponent Silicate Glasses by Electron Irradiation

2014 ◽  
Vol 29 (10) ◽  
pp. 1018
Author(s):  
FU Xin-Jie ◽  
SONG Li-Xin ◽  
LI Jia-Cheng
Keyword(s):  
Electron Irradiation ◽  
Silicate Glasses

Nanoemulsions- A better Approach for Anti Diabeticdrugs Delivering

2020 ◽  
Vol 17 ◽  
Author(s):  
V. Manimaran ◽  
Ponnurengam Malliappan Sivakumar ◽  
J. Narayanan ◽  
Shanmugam Parthasarathi ◽  
Pranav Kumar Prabhakar
Keyword(s):  
Aqueous Phase ◽  
Therapeutic Agent ◽  
Antidiabetic Drugs ◽  
Optical Behaviour ◽  
Antimicrobial Drugs ◽  
Drug Degradation ◽  
Oil In Water ◽  
Drug Technology ◽  
Human Use ◽  
Poor Absorption

: Conventional delivery of antidiabetic drugs faces many problems like poor absorption, low bioavailability, and drug degradation. Nanoemulsion is a unique drug technology which is very suitable for the delivery of antidiabetic drugs. In recent years the flaws of delivering anti-hypoglycaemic drugs have been overcome by choosing nanoemulsion drug technology. They are thermodynamically stable and also deliver the therapeutic agent for a longer duration. Generally, Nanoemulsions are made up of either oil-in-water or water-in-oil and size of the droplets is from fifty to thousand nanometer. Surfactants are critical substances which are added in the manufacturing of nanoemulsions. Only the surfactants which are approved for human use can be utilized in the manufacturing of nanoemulsions. Generally, the preparation of emulsions includes mixing of the aqueous phase and organic phase and using surfactant with proper agitation. Nanoemulsions are used for antimicrobial drugs, and they are also used in the prophylaxis of cancer, diabetics. Reduction in the droplet size may cause variation in the elastic and optical behaviour of nanoemulsions.

Europium oxidation state and local structure in silicate glasses

2012 ◽  
Vol 97 (5-6) ◽  
pp. 918-929 ◽  
Author(s):  
M. R. Cicconi ◽  
G. Giuli ◽  
E. Paris ◽  
W. Ertel-Ingrisch ◽  
P. Ulmer ◽  
...  
Keyword(s):  
Oxidation State ◽  
Local Structure ◽  
Silicate Glasses ◽  
State And Local

scholarly journals Polarimetric Properties of Blazars Caught by the WEBT

Galaxies ◽  
2021 ◽  
Vol 9 (2) ◽  
pp. 42
Author(s):  
Claudia M. Raiteri ◽  
Massimo Villata
Keyword(s):  
Active Galactic Nuclei ◽  
Galactic Nuclei ◽  
Plasma Jets ◽  
Line Of Sight ◽  
Optical Behaviour ◽  
Relativistic Jets ◽  
Comprehensive Picture ◽  
Multi Wavelength ◽  
Extreme Variability ◽  
Continuous Range

Active galactic nuclei come in many varieties. A minority of them are radio-loud, and exhibit two opposite prominent plasma jets extending from the proximity of the supermassive black hole up to megaparsec distances. When one of the relativistic jets is oriented closely to the line of sight, its emission is Doppler beamed and these objects show extreme variability properties at all wavelengths. These are called “blazars”. The unpredictable blazar variability, occurring on a continuous range of time-scales, from minutes to years, is most effectively investigated in a multi-wavelength context. Ground-based and space observations together contribute to give us a comprehensive picture of the blazar emission properties from the radio to the γ-ray band. Moreover, in recent years, a lot of effort has been devoted to the observation and analysis of the blazar polarimetric radio and optical behaviour, showing strong variability of both the polarisation degree and angle. The Whole Earth Blazar Telescope (WEBT) Collaboration, involving many tens of astronomers all around the globe, has been monitoring several blazars since 1997. The results of the corresponding data analysis have contributed to the understanding of the blazar phenomenon, particularly stressing the viability of a geometrical interpretation of the blazar variability. We review here the most significant polarimetric results achieved in the WEBT studies.

scholarly journals Modeling the Nanoindentation Response of Silicate Glasses by Peridynamic Simulations

2021 ◽  
Author(s):  
Yuzhe Cao ◽  
Maryam Kazembeyki ◽  
Longwen Tang ◽  
NM Anoop Krishnan ◽  
Morten M. Smedskjaer ◽  
...  
Keyword(s):  
Silicate Glasses

Dielectric dynamics and optical behaviour of surfactant free LC/silicone oil based non-aqueous emulsions

2021 ◽  
pp. 1-10
Author(s):  
Ravi K. Shukla ◽  
Ashok Chaudhary ◽  
K. K. Raina
Keyword(s):  
Silicone Oil ◽  
Optical Behaviour

scholarly journals Low-temperature nucleation anomaly in silicate glasses shown to be artifact in a 5BaO·8SiO2 glass

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Xinsheng Xia ◽  
D. C. Van Hoesen ◽  
Matthew E. McKenzie ◽  
Randall E. Youngman ◽  
K. F. Kelton
Keyword(s):  
Nucleation Rate ◽  
Experimental Approach ◽  
Cluster Formation ◽  
Heating Time ◽  
Silicate Glasses ◽  
Nucleation Theory ◽  
Classical Nucleation Theory ◽  
Real Phenomenon ◽  
Satisfactory Answer ◽  
Over 40 Years

AbstractFor over 40 years, measurements of the nucleation rates in a large number of silicate glasses have indicated a breakdown in the Classical Nucleation Theory at temperatures below that of the peak nucleation rate. The data show that instead of steadily decreasing with decreasing temperature, the work of critical cluster formation enters a plateau and even starts to increase. Many explanations have been offered to explain this anomaly, but none have provided a satisfactory answer. We present an experimental approach to demonstrate explicitly for the example of a 5BaO ∙ 8SiO2 glass that the anomaly is not a real phenomenon, but instead an artifact arising from an insufficient heating time at low temperatures. Heating times much longer than previously used at a temperature 50 K below the peak nucleation rate temperature give results that are consistent with the predictions of the Classical Nucleation Theory. These results raise the question of whether the claimed anomaly is also an artifact in other glasses.

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