Preparation, Structure, Optical and Morphological Properties of Co, Ga2O3 Co-Doped ZnS/Se

2019 ◽  
Vol 962 ◽  
pp. 22-28
Author(s):  
Yong Pan ◽  
Li Wang ◽  
Dong Wen Gao ◽  
Shu Feng Li ◽  
Xiao Wei Han
Keyword(s):  
Mass Loss Rate ◽  
Base Material ◽  
Optical Loss ◽  
Morphological Properties ◽  
Mid Infrared ◽  
Application Range ◽  
Zinc Blende ◽  
Ceramic Targets ◽  
Chalcogenide Compound ◽  
Optimum Doping Concentration

The material of doping transition metal (TM) in chalcogenide compound such as ZnS and ZnSe can be used in sensors, nonlinear optics, optical thin-films and mid-infrared area because of their faster optical response time, wider transparency range of mid-infrared and higher mid-infrared transmittance, low optical loss and phonon energy. In this paper, the ceramic targets of (ZnS/Se)0.4(Co)x(Ga2O3)0.6-x(x=0.1, 0.3 and 0.5) were prepared by high temperature solid state reaction. The mass loss rate, shrinkage rate and molar ration were calculated. XRD, absorption spectrum and AFM&OM were investigated. All of the results are shown that the optimum doping concentration is (ZnS/Se)0.4(Co)0.5(Ga2O3)0.1(namely x=0.5), and the optimum intering temperature are in the range 1000~1200°C. Besides, the zinc-blende structure on ceramics targets was confirmed by XRD. A broad application range from VIS to Mid-infrared was suggested by absorption spectra. The optimal base material ZnSe was proved by AFM and OM. All these results indicate that bulks of (ZnS/Se)0.4(Co)x(Ga2O3)0.6-xare most promising materials in future

scholarly journals 1.16. 4.5 to 11.7 microns spectrophotometric observations of the Galactic bulge by the MIRS/IRTS

1998 ◽  
Vol 184 ◽  
pp. 47-47
Author(s):  
Kin-Wing Chan ◽  
T. L. Roellig ◽  
T. Onaka ◽  
I. Yamamura ◽  
T. Tanabé
Keyword(s):  
Interstellar Medium ◽  
Mass Loss Rate ◽  
Life Time ◽  
High Mass ◽  
Galactic Latitude ◽  
Galactic Bulge ◽  
Stellar Content ◽  
Mid Infrared ◽  
Evolved Stars ◽  
Infrared Background

Using the Mid-Infrared (MIRS) on board the Infrared Telescope in Space (IRTS) we obtained the 4.5 to 11.7 μm spectra of the stellar populations and diffuse interstellar medium in the Galactic bulge (l ≈ 8.7°, b ≈ 2.9, 4.0, 4.7, and 5.7°). Below galactic latitute of 4.0° the mid-infrared background spectra in the bulge are similar to the spectrum of M and K giants. The UIR bands (6.2, 7.7, 8.6, and 11.3 μm) are also detected in these regions and they are likely arising from the diffuse interstellar medium in the bulge. Above galactic latitude of 4.0°, the mid-infrared background spectra are similar to the spectrum of those evolved stars with high mass-loss rate detected by IRAS. One likely interpretation is that this background emission arises predominantly from these stars with very low luminosities that have not been detected by IRAS. The main-sequence life time for such low luminosity evolved stars is at least 10 Gyr, even in the metal poor cases. If these low luminosity evolved stars are metal-rich then the age would be much older. Thus, the existence of a large number (~ 75) of such low luminosity evolved stars in a small region (8′ × 8′) in the bulge would have significant impact on our understanding of the stellar content and the age of the Galactic bulge.

scholarly journals Experimental Study on Slope Deformation Monitoring Based on a Combined Optical Fiber Transducer

2017 ◽  
Vol 2017 ◽  
pp. 1-11 ◽  
Author(s):  
Yong Zheng ◽  
Dong-Yan Liu ◽  
Zheng-Wei Zhu ◽  
Hong-Lin Liu ◽  
Bang Liu
Keyword(s):  
Optical Fiber ◽  
Empirical Formula ◽  
Large Scale ◽  
Base Material ◽  
Optical Loss ◽  
Deformation Monitoring ◽  
Landslide Monitoring ◽  
Sandy Clay ◽  
Measured Displacement ◽  
Clay Slopes

Landslide monitoring is very important in predicting the behavior of landslides, thereby ensuring environment, life, and property safety. On the basis of our previous studies, a novel combined optic fiber transducer (COFT) for landslides monitoring and the related analysis methods are presented. Based on the principles of optical fiber microbending loss, the empirical formula of the shearing displacement of sliding body versus optical loss was established through a stretching test of optical fiber bowknot. Then the COFT grouting direct shearing tests, a large-scale landslide model test, and numerical modeling verification with FLAC3D are carried out. According to the results, the initial measurement precision of the designed COFT in sandy clay is 1 mm; its monitoring sliding distance is larger than 26.5 mm. The calculated values based on empirical formula are in good agreement with the laboratory tests and numerical simulation results. When the ratio of cement and sand in mortar is 1 : 5, the error between the calculated displacement and the measured displacement of sliding surface is the smallest. The COFT with expandable polystyrene (EPS) as its base material performs better in monitoring sandy clay slopes because both the error and the mean square deviation of the empirical formula are smaller.

scholarly journals Investigation of Ultrasonic Treatment on Physicochemical, Structural and Morphological Properties of Sodium Alginate/AgNPs/Apple Polyphenol Films and Its Preservation Effect on Strawberry

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 2096
Author(s):  
Wenting Lan ◽  
Siying Li ◽  
Shiti Shama ◽  
Yuqing Zhao ◽  
Dur E. Sameen ◽  
...  
Keyword(s):  
Antibacterial Activity ◽  
Composite Film ◽  
Sodium Alginate ◽  
Food Packaging ◽  
Base Material ◽  
Morphological Properties ◽  
Vapor Permeability ◽  
Sem Images ◽  
Active Food Packaging ◽  
Ultrasonic Time

An antibacterial and anti-oxidation composite film was prepared by a casting method using sodium alginate (SA) and apple polyphenols (APPs) as the base material and glycerol as the plasticizer. Silver nanoparticles (AgNPs) were deposited by ultrasonic-assisted electrospray method. The degree of influence of the addition ratio of SA and AgNPs and different ultrasonic time on the mechanical properties, barrier properties, optical properties, and hydrophilicity of the composite film was explored. The composite films were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the SA: AgNPs ratio of 7:3 and the ultrasonic time for 30 min have the best comprehensive performance, and SA/AgNPs/APP films showed the lowest water vapor permeability value of 0.75 × 10−11 g/m·s·Pa. The composite film has good strength and softness, with tensile strength (TS) and elongation at break (E) at 23.94 MPa and 29.18%, respectively. SEM images showed that the surface of the composite film was smooth and the AgNPs’ distribution was uniform. The composite film showed broad antibacterial activity, and the antibacterial activity of Escherichia coli (92.01%) was higher than that of Staphylococcus aureus (91.26%). However, due to the addition of APP, its antioxidant activity can reach 98.39%, which has a synergistic effect on antibacterial activity. For strawberry as a model, the results showed that this composite film can prolong the shelf life of strawberries for about 8 days at 4 °C, effectively maintaining their storage quality. Compared with the commonly used PE(Polyethylene film) film on the market, it has a greater fresh-keeping effect and can be used as an active food packaging material.

scholarly journals Dielectric Metasurface-Based High-Efficiency Mid-Infrared Optical Filter

Nanomaterials ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 938 ◽  
Author(s):  
Fei Shen ◽  
Qianlong Kang ◽  
Jingjing Wang ◽  
Kai Guo ◽  
Qingfeng Zhou ◽  
...  
Keyword(s):  
High Efficiency ◽  
Incident Angle ◽  
Optical Filter ◽  
Optical Loss ◽  
Mid Infrared ◽  
Dipole Resonance ◽  
Mode Decomposition ◽  
Wide Range ◽  
Si Nanodisk ◽  
Dielectric Metasurface

Dielectric nanoresonantors may generate both electric and magnetic Mie resonances with low optical loss, thereby offering highly efficient paths for obtaining integrated optical devices. In this paper, we propose and design an optical filter with a high working efficiency in the mid-infrared (mid-IR) range, based on an all-dielectric metasurface composed of silicon (Si) nanodisk arrays. We numerically demonstrate that, by increasing the diameter of the Si nanodisk, the range of the proposed reflective optical filter could effectively cover a wide range of operation wavelengths, from 3.8 μm to 4.7 μm, with the reflection efficiencies reaching to almost 100%. The electromagnetic eigen-mode decomposition of the silicon nanodisk shows that the proposed optical filter is based on the excitation of the electric dipole resonance. In addition, we demonstrate that the proposed filter has other important advantages of polarization-independence and incident-angle independence, ranging from 0° to 20° at the resonance dip, which can be used in a broad range of applications, such as sensing, imaging, and energy harvesting.

Does 3rd dredge-up reduce AGB mass-loss?

2018 ◽  
Vol 14 (S343) ◽  
pp. 529-530
Author(s):  
Stefan Uttenthaler ◽  
Iain McDonald ◽  
Klaus Bernhard ◽  
Sergio Cristallo ◽  
David Gobrecht
Keyword(s):  
Mass Loss ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Pulsation Period ◽  
Agb Stars ◽  
Mid Infrared ◽  
The Third ◽  
Previous Sample ◽  
Good Probe

AbstractWe follow up on a previous finding that Miras containing the third dredge-up (3DUP) indicator technetium (Tc) in their atmosphere form a different sequence of K – [22] colour as a function of pulsation period than Miras without Tc. A near-to-mid-infrared colour such as K – [22] is a good probe for the dust mass-loss rate (MLR) of these AGB stars. Contrary to what one might naïvely expect, Tc-poor Miras show redderK – [22] colours (i.e. higher dust MLRs) than Tc-rich Miras at a given period. In the follow-up work, the previous sample is extended and the analysis is expanded towards other colours and ISO dust spectra to check if the previous finding is due to a specific dust feature in the 22 μm band. We also investigate if the same two sequences can be revealed in the gas MLR. Different hypotheses to explain the observation of two sequences in the P vs. K – [22] diagram are discussed and tested, but so far none of them convincingly explains the observations.

Strength Class Prediction of Sardinia Grown Timber by Means of Non Destructive Parameters

2013 ◽  
Vol 778 ◽  
pp. 191-198 ◽  
Author(s):  
Giovanna Concu ◽  
Barbara de Nicolo ◽  
Nicoletta Trulli ◽  
Monica Valdés ◽  
Massimo Fragiacomo
Keyword(s):  
Mechanical Properties ◽  
Strength Class ◽  
Ring Width ◽  
Base Material ◽  
Ultrasonic Pulse Velocity ◽  
Pulse Velocity ◽  
Wood Products ◽  
Morphological Properties ◽  
Class Prediction ◽  
Non Destructive

In Italy timber and wood products are becoming increasingly used for building constructions due to their excellent physics and mechanical properties. International Codes require the use of wood previously graded according to the current regulation. This paper reports the preliminary results of an experimental campaign aimed at verifying the reliability of the use of Sardinian timber as structural material. For this purpose Maritime Pine boards from two different Sardinian areas have been analyzed and visual strength graded. Physical and morphological properties (density, knots, clusters knot, resin pockets, deviation of the grain, annual ring width position of board respect to the pith, humidity, etc.) along with mechanical and non destructive properties (elastic modulus, tensile strength, ultrasonic pulse velocity) have been checked. Timber properties have been statistically evaluated in order to identify the performance of the base material. Regression analyses have been carried out by studying the correlation between non destructive parameters and mechanical properties in order to define a criterion for predicting the strength class of the base material.

scholarly journals Bow shocks, bow waves, and dust waves – III. Diagnostics

2019 ◽  
Vol 489 (2) ◽  
pp. 2142-2158 ◽  
Author(s):  
William J Henney ◽  
S J Arthur
Keyword(s):  
Mass Loss ◽  
Loss Rate ◽  
Mass Loss Rate ◽  
Previous Method ◽  
Radiative Energy ◽  
Mid Infrared ◽  
Bow Waves ◽  
Bow Shocks ◽  
Infrared Wavelengths ◽  
Loss Rates

ABSTRACT Stellar bow shocks, bow waves, and dust waves all result from the action of a star’s wind and radiation pressure on a stream of dusty plasma that flows past it. The dust in these bows emits prominently at mid-infrared wavelengths in the range 8 to   60 $\mu$m. We propose a novel diagnostic method, the τ–η diagram, for analysing these bows, which is based on comparing the fractions of stellar radiative energy and stellar radiative momentum that is trapped by the bow shell. This diagram allows the discrimination of wind-supported bow shocks, radiation-supported bow waves, and dust waves in which grains decouple from the gas. For the wind-supported bow shocks, it allows the stellar wind mass-loss rate to be determined. We critically compare our method with a previous method that has been proposed for determining wind mass-loss rates from bow shock observations. This comparison points to ways in which both methods can be improved and suggests a downward revision by a factor of two with respect to previously reported mass-loss rates. From a sample of 23 mid-infrared bow-shaped sources, we identify at least four strong candidates for radiation-supported bow waves, which need to be confirmed by more detailed studies, but no strong candidates for dust waves.

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