Stress optical behaviour of ammonium pentaborate under linear and hydrostatic stresses

: 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.

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Polarimetric Properties of Blazars Caught by the WEBT

Galaxies ◽

10.3390/galaxies9020042 ◽

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.

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

Materials Chemistry and Physics ◽

10.1016/j.matchemphys.2021.124787 ◽

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

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

Liquid Crystals ◽

10.1080/02678292.2021.1931972 ◽

2021 ◽

pp. 1-10

Author(s):

Ravi K. Shukla ◽

Ashok Chaudhary ◽

K. K. Raina

Keyword(s):

Silicone Oil ◽

Optical Behaviour

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Use of the AE Effect to Determine the Stresses State in AAC Masonry Walls under Compression

Materials ◽

10.3390/ma14133459 ◽

2021 ◽

Vol 14 (13) ◽

pp. 3459

Author(s):

Radosław Jasiński ◽

Krzysztof Stebel ◽

Paweł Kielan

Keyword(s):

Ultrasonic Waves ◽

Image Correlation ◽

Masonry Walls ◽

Acceptable Error ◽

Compressive Stresses ◽

Deformation State ◽

Hydrostatic Stresses ◽

Stress States ◽

The Impact ◽

Masonry Units

Safety and reliability of constructions operated are predicted using the known mechanical properties of materials and geometry of cross-sections, and also the known internal forces. The extensometry technique (electro-resistant tensometers, wire gauges, sensor systems) is a common method applied under laboratory conditions to determine the deformation state of a material. The construction sector rarely uses ultrasonic extensometry with the acoustoelastic (AE) method which is based on the relation between the direction of ultrasonic waves and the direction of normal stresses. It is generally used to identify stress states of machine or vehicles parts, mainly made of steel, characterized by high homogeneity and a lack of inherent internal defects. The AE effect was detected in autoclaved aerated concrete (AAC), which is usually used in masonry units. The acoustoelastic effect was used in the tests described to identify the complex stress state in masonry walls (masonry units) made of AAC. At first, the relationships were determined for mean hydrostatic stresses P and mean compressive stresses σ3 with relation to velocities of the longitudinal ultrasonic wave cp. These stresses were used to determine stresses σ3. The discrete approach was used which consists in analyzing single masonry units. Changes in velocity of longitudinal waves were identified at a test stand to control the stress states of an element tested by the digital image correlation (DIC) technique. The analyses involved density and the impact of moisture content of AAC. Then, the method was verified on nine walls subjected to axial compression and the model was validated with the FEM micromodel. It was demonstrated that mean compressive stresses σ3 and hydrostatic stresses, which were determined for the masonry using the method considered, could be determined even up to ca. 75% of failure stresses at the acceptable error level of 15%. Stresses σ1 parallel to bed joints were calculated using the known mean hydrostatic stresses and mean compressive stresses σ3.

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Theoretical insight into electronic and optical behaviour of H-adsorbed Zn-terminated Zn3N2-(100)-non-polar surface

Vacuum ◽

10.1016/j.vacuum.2021.110467 ◽

2021 ◽

pp. 110467

Author(s):

M. Kaur ◽

K. Kabra ◽

M. Rérat ◽

G. Sharma

Keyword(s):

Optical Behaviour ◽

Polar Surface ◽

Theoretical Insight ◽

Insight Into

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Optical behaviour of VTE treated near stoichiometric LiNbO3 crystals

Solid State Communications ◽

10.1016/j.ssc.2005.11.042 ◽

2006 ◽

Vol 137 (6) ◽

pp. 283-287 ◽

Cited By ~ 17

Author(s):

S. Kar ◽

R. Bhatt ◽

V. Shukla ◽

R.K. Choubey ◽

P. Sen ◽

...

Keyword(s):

Optical Behaviour

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The optical behaviour of snow during a melting season at Ny Ålesund (Svalbard, Norway)

10.5194/egusphere-egu21-14667 ◽

2021 ◽

Author(s):

Roberto Salzano ◽

Christian Lanconelli ◽

Giulio Esposito ◽

Marco Giusto ◽

Mauro Montagnoli ◽

...

Keyword(s):

Climate Change ◽

Snow Cover ◽

Full Range ◽

Time Lapse ◽

Test Site ◽

Remotely Sensed ◽

Optical Behaviour ◽

Remotely Sensed Data ◽

Snow Cover Area ◽

Significant Information

Polar areas are the most sensitive targets of the climate change and the continuous monitoring of the cryosphere represents a critical issue. The satellite remote sensing can fill this gap but further integration between remotely-sensed multi-spectral images and field data is crucial to validate retrieval algorithms and climatological models. The optical behaviour of snow, at different wavelengths, provides significant information about the micro-physical characteristics of the surface and this allow to discriminate different snow/ice covers. The aim of this work is to present an approach based on combining unmanned observations on spectral albedo and on the analysis of time-lapse images of sky and ground conditions in an Arctic test-site (Svalbard, Norway). Terrestrial photography can provide, in fact, important information about the cloud cover and support the discrimination between white-sky or clear-sky illuminating conditions. Similarly, time-lapse cameras can provide a detailed description of the snow cover, estimating the fractional snow cover area. The spectral albedo was obtained by a narrow band device that was compared to a full-range commercial system and to remotely sensed data acquired during the 2015 spring/summer period at the Amundsen - Nobile Climate Change Tower (Ny &#197;lesund). The results confirmed the possibility to have continuous observations of the snow surface (microphisical) characteristics and highlighted the opportunity to monitor the spectral variations of snowed surfaces during the melting period. It was possible, therefore, to estimate spectral indexes, such as NDSI and SWIR albedo, and to found interesting links between both features and air/ground temperatures, wind-speed and precipitations. Different melting phases were detected and different processes were associated with the observed spectral variations.

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