Functionalization of Surfaces with Optical Coatings Produced by PVD Magnetron Sputtering

2016 ◽  
pp. 170-207
Author(s):  
Walter Raniero ◽  
Gianantonio Della Mea ◽  
Matteo Campostrini
Keyword(s):  
Magnetron Sputtering ◽  
Optical Filters ◽  
Incident Radiation ◽  
Physical Principle ◽  
Research Field ◽  
Optical Responses ◽  
Inorganic Coatings ◽  
Materials Used ◽  
Good Homogeneity ◽  
Real Thickness

This chapter describes the functionalization of the surface of the glass through thin film inorganic coatings. Such filters called dichroic filters, following the physical principle of interference of light using the rules of optical physics. The design of the optical multilayer materials with high and low refractive index and optimizing the predetermined optical responses. The AFM quantify the real thickness and, calibrate the deposition plant, using as an input data for the simulation to evaluate the dispersion index refraction and absorption. The dichroic filters separate the incident radiation into two or more predetermined optical bands. The materials used are deposited using PVD Reactive Magnetron Sputtering, allows to increase the deposition rate, to obtain good homogeneity range of the surface deposited. The set point of deposition which allows to obtain stoichiometric oxides is analyzed with the technique RBS. These optical filters, also called dichroic are applied in the research field of the splitting photovoltaic concentration.

Piezoelectric Scanner

2021 ◽  
pp. 277-298
Author(s):  
C. Julian Chen
Keyword(s):  
Lead Zirconate Titanate ◽  
Piezoelectric Materials ◽  
Calibration Method ◽  
Lead Zirconate ◽  
Physical Principle ◽  
Electrical Measurements ◽  
Linear Behavior ◽  
Materials Used ◽  
Improved Design ◽  
Titanate Ceramics

This chapter discusses the physical principle, design, and characterization of piezoelectric scanners, which is the heart of STM and AFM. The concept of piezoelectricity is introduced at the elementary level. Two major piezoelectric materials used in STM and AFM, quartz and lead zirconate titanate ceramics (PZT), are described. After a brief discussion of the tripod scanner and the bimorph, much emphasis is on the most important scanner in STM and AFM: the tube scanner. A step-by-step derivation of the deflection formula is presented. The in-situ testing and calibration method based on pure electrical measurements is described. The formulas of the resonance frequencies are also presented. To compensate the non-linear behavior of the tube scanner, an improved design, the S-scanner, is described. Finally, a step-by-step procedure to repole a depoled piezo is presented.

scholarly journals Design, Implementation and Characterization of Cavity for Absolute Radiometer

2021 ◽  
Vol 9 ◽  
Author(s):  
Franciele Carlesso ◽  
Luis E. A. Vieira ◽  
Luiz A. Berni ◽  
Graziela da S. Savonov
Keyword(s):  
Specular Reflection ◽  
Electrical Power ◽  
Black Body ◽  
Incident Radiation ◽  
Total Solar Irradiance ◽  
Physical Principle ◽  
Angle Of Incidence ◽  
The Impact ◽  
Bidirectional Reflectance Distribution

Absolute radiometers are based on electrical substitution radiometers, which compare optical and electrical power. The same physical principle applies to standard reference detectors operating at cryogenic temperatures and room temperature radiometers for total solar irradiance (TSI) measurements. Both types rely on the cavity with an internal low-reflectance coating to absorb incident radiation similar to a black body. The cavity shape design requires an analysis of the coating reflection properties. Like many materials, ultra-black Ni-P exhibits a mixture of diffuse and specular reflection that depends on the angle of incidence of light in the pores. We employed ray-tracing software to study the impact of the geometry on the absorptivity and distribution of the scattered rays. We describe the scattering model of the black coating in terms of the bidirectional reflectance distribution function. Also, we examined the difficulties of Ni-P electroless deposition and blackening inside the cavity. The measured absorptance of the cavity showed some discrepancies of the simulated absorptance mostly probably due to Ni-P non-uniformity coating.

Guidelines for terminology for microtechnology in clinical laboratories (IUPAC Technical Report)

2006 ◽  
Vol 78 (3) ◽  
pp. 677-684
Author(s):  
Peter Wilding ◽  
Thomas Joos ◽  
Larry J. Kricka ◽  
Leming Shi
Keyword(s):  
Gene Expression ◽  
Clinical Laboratory ◽  
Physical Principle ◽  
High Density ◽  
Clinical Laboratories ◽  
Technical Report ◽  
Materials Used

There is no formal terminology used to describe the scope and use of microtechnology in the clinical laboratory. For many laboratory scientists, the word "microchip" is synonymous with high-density microarrays used primarily for investigating gene expression. The document proposes a system of "categories" and "descriptors" that facilitates the classification of a device in a way that communicates details of its function and analytical role, and describes the analytical principle involved and the methods and materials used for its manufacture. Adoption of this system would enable scientists to employ four descriptors that clearly delineate the function, analytical role, and chemical or physical principle involved in the device. Examples of existing commercial devices are given to illustrate the utility of the system.

Effect of composition on thermal stability and microstructural behaviour of non-prototype material (CaO-Fe2O3)

2021 ◽  
Vol 15 (1) ◽  
pp. 7885-7893
Author(s):  
Vijay Kumar Pandey ◽  
Sunil Kumar Jatav ◽  
Upendra Pandel ◽  
Rajendra Kumar Duchaniya
Keyword(s):  
Heat Treatment ◽  
Thermal Stability ◽  
Research Field ◽  
Severe Accident ◽  
Liquid Form ◽  
Morphological Studies ◽  
Heat Treated ◽  
Before And After ◽  
Materials Used ◽  
Nuclear Severe Accidents

The role of simulant materials becomes necessary for the predictive study of the nuclear severe accident phenomena due to its similarity with corium (a liquid form of UO2 and steel). Since simulant material is eco-friendly and has similar properties to corium, it has been widely used in the research field of severe accident management. In this study, material CaO-Fe2O3 a non-eutectic binary mixture is considered for characterization purpose to address the thermophysical properties at different compositional ratios. The CaO-Fe2O3 powder mixture was prepared in mortar for 40 minutes manually to form a homogeneous mixture and then cylindrical pellets prepared at five different ratios with the help of the phase diagram. Further, these pellets were heat-treated at 1200°C for three hours soaking time to address its thermal stability in a programmable electric furnace. Finally, pellets ground into powder form manually for further characterization. Initially, the weight loss analysis was reported by measurement of dimensions of pellets before and after heat treatment. The thermal properties, phase analysis, and morphological studies have been carried out through DSC, XRD and FE-SEM in laboratory and results were discussed in the context of the property of ideal simulant materials used for the study of nuclear severe accidents. The melting point of all the samples were found stable (1200°C-1230°C) and values of activation energy and specific heat were well synchronized between with and without heat-treated samples. Dislocation density of samples increases significantly with increasing the proportion value of calcium oxide after heat treatment.

scholarly journals Optical properties of CdTe thin film obtained by high-frequency magnetron sputtering method

2021 ◽  
pp. 88-95
Author(s):  
Andrei I. Kashuba ◽  
Bogdan V. Andriyevsky ◽  
Hrigorii A. Ilchuk ◽  
Mikhal Piasecki ◽  
Igor’ V. Semkiv ◽  
...  
Keyword(s):  
Thin Film ◽  
Optical Properties ◽  
Solar Cells ◽  
Magnetron Sputtering ◽  
Raman Spectra ◽  
High Frequency ◽  
Research Field ◽  
Cdte Thin Film ◽  
Direct Energy ◽  
Absorbing Layer

Cadmium telluride (CdTe) thin films relate to AII BVI compounds and show semiconductor behaviour. They present an important research field because of their wide application in various optoelectronic devices. CdTe-based solar cells attract attention since CdTe is characterised by the direct energy bandgap Eg and high absorbance, which makes it an excellent light-absorbing layer of solar cells. Material evaporation in vacuum by using the high-frequency magnetron sputtering method is one of the most advantageous methods for obtaining uniform films. The present work is dedicated to the investigation of the optical properties of CdTe thin film, which is produced on quarts substrate by the high-frequency magnetro sputtering method. The optical transmission, reflectivity, and μ-Raman spectra of the CdTe thin film have been determined. Linearity of the spectral dependence of the coefficient of optical absorption α of CdTe thin film in the coordinates (αhν)2  vs hν indicates for the direct character of optical transitions corresponding to the long-wavelength edge of fundamental absorption. The optical bandgap of the studied CdTe thin film is found to be Eg = 1.53 eV. The peaks of the experimental m-Raman spectra at 121; 139; 142; 167 and 331 cm–1 are attributed to the phonons in crystalline CdTe and Te.

Study Regarding the Cavitation Erosion Behaviour and Residual Stresses of Impact Resistant Hardfacing Materials

2014 ◽  
Vol 1029 ◽  
pp. 146-151
Author(s):  
Evelina Roxana Secosan ◽  
Relu Costel Ciubotariu ◽  
Vasile Cojocaru ◽  
Doina Frunzaverde ◽  
Constantin Viorel Câmpian
Keyword(s):  
Residual Stresses ◽  
Cavitation Erosion ◽  
Hydraulic Turbine ◽  
Research Field ◽  
Operating Conditions ◽  
Hole Drilling ◽  
Hardfacing Alloy ◽  
Hardness Tests ◽  
Materials Used ◽  
Cavitation Erosion Resistance

In the last twenty years the cavitation erosion resistance of various welded materials was subject of extensive studies. Despite these, the research field is still opened. The multitude of materials used for the fabrication of hydraulic equipment and the variety of the operating conditions in hydropower units require adapted solutions. This paper presents the investigations made on welded overlays realized using an impact resistant hardfacing alloy, recommended by manufacturers for protection against cavitation erosion. The material was characterized by metallographic investigations (light microscopy, scanning electron microscopy and EDX–analyse), Vickers micro hardness tests, residual stresses measurements carried out by the hole-drilling strain-gage method and cavitation erosion tests using the vibratory method. The results of the cavitation erosion tests were correlated to the behaviour of the martensitic stainless steel 1.4313 (grade X3CrNiMo13-4 corresponding to EN 10088-3) frequently used for the manufacturing of the hydraulic turbine components.

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