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Thermal optical measurement

TERA (see tera in alphabetical listings) TOM thermal optical measurement... [Pg.614]

Polarization which can be induced in nonconducting materials by means of an externally appHed electric field is one of the most important parameters in the theory of insulators, which are called dielectrics when their polarizabiUty is under consideration (1). Experimental investigations have shown that these materials can be divided into linear and nonlinear dielectrics in accordance with their behavior in a realizable range of the electric field. The electric polarization PI of linear dielectrics depends linearly on the electric field E, whereas that of nonlinear dielectrics is a nonlinear function of the electric field (2). The polarization values which can be measured in linear (normal) dielectrics upon appHcation of experimentally attainable electric fields are usually small. However, a certain group of nonlinear dielectrics exhibit polarization values which are several orders of magnitude larger than those observed in normal dielectrics (3). Consequentiy, a number of useful physical properties related to the polarization of the materials, such as elastic, thermal, optical, electromechanical, etc, are observed in these groups of nonlinear dielectrics (4). [Pg.202]

Improved heat-resistant UV compositions for optical fiber applications These compositions are nonurethane UV cure compositions that have neither carbamate moieties nor long-chain poly(alkylene oxide) soft segments and exhibit inherently better thermal stability measured by thermogravimetric analysis (TGA) than typical coatings for optical fibers based on urethane acrylate oligomers. [Pg.245]

Organic carbon (OC) and elemental carbon (EC) concentrations in smoke aerosol can be measured by using a semicontinuous thermal-optical OC/EC instruments [18]. Water-soluble organic carbon (WSOC) and water-soluble ions can be detected in smoke plumes with a PILS combined with a total organic carbon analyzer [30] and IC [19]. Besides smoke-specific tracers, the HR-ToF-AMS enables to study the concentrations of organic matter (OM), nitrate, ammonium, sulfate, and chloride in smoke particles [30]. Black carbon (BC) can be measured in real-time with several instruments, e.g., with aethalometer [19], multi-angle absorption photometer [29], and particle soot absorption photometer [25]. [Pg.108]

The transport of thermal energy can be broken down into one or more of three mechanisms conduction--heat transfer via atomic vibrations in solids or kinetic interaction amongst atoms in gases1 convection - - heat rapidly removed from a surface by a mobile fluid or gas and radiation—heat transferred through a vacuum by electromagnetic waves. The discussion will begin with brief explanations of each. These concepts are important background in the optical measurement of temperature (optical pyrometry) and in experimental measurement of the thermally conductive behavior of materials. [Pg.199]

Ion implantation is widely used in semiconductor device technology to locally alter the electrical properties of materials. Since only the electrical properties are generally of interest, the optical properties of implanted semiconductors are not often reported in detail, despite the excellent sensitivity of optical investigation to the removal of damage by post-implantation thermal annealing. Optical measurements could be useful to GaN researchers seeking an optimal post-implant annealing procedure. [Pg.466]

A different approach was taken by Kumar and associates [61]. Fie also embedded metals in polymers, but used as his precursor the polymer and not the monomer. In his first study a composite material containing amorphous Cu nanoparticles and nanocrystalline CU2O embedded in polyanUine matrices was prepared by a sonochemical method. These composite materials were obtained from the soni-cation of copper (II) acetate when aniline or 1% v/v aniline-water was used as the solvent. Mechanisms for the formation of these products are proposed and discussed. The physical and thermal properties of the as-prepared composite materials are presented. A band gap of 2.61 eV is estimated from optical measurements for the as-prepared CU2O in polyaniline. [Pg.126]

In this chapter we investigate and discuss the thermal, optical, electrical properties of the oligothiophene derivatives by means of differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA), and UV-Vis spectroscopy. The thin films of these compounds produced by solution cast and vacuum deposition methods are characterised by AFM measurements in contact and non-contact mode, and by X-ray diffraction. Finally, an ultra-thin OFET is built, and the transistor characteristics are determined. [Pg.680]

A variety of methods have been applied to the measurement of EC and OC in aerosol samples with the thermal, thermal optical reflectance (TOR), and thermal manganese oxidation (TMO) methods being the most popular. Understanding the operational principles of these methods is often necessary for the interpretation of reported EC and OC data. [Pg.675]

In this work, erbium doped strontium barium niobate glasses have been irradiated with a femtosecond laser. The properties of these glasses and the changes induced by a cw laser have been studied in a previous paper . Optical measurements show the changes of the local structure in a localized area after the irradiation and they arc compared with the bulk glass ceramic sample obtained by thermal treatment with a furnace. [Pg.573]

Thermal band gaps and first exciton levels are deduced from optical measurements by using the appropriate Kq/k for each azide. Values in kJ/mole. 0 = photoelectric work function Handbook of Physics and Chemistry Chemical Rubber Co., 1972). Values in kJ/mole. [Pg.255]

The transducer transforms the chemical information into a measurable signal it can take many forms depending upon the parameters being measured. The most common are electrochemical, optical, mass and thermal. The measured parameters may be converted into an electrical signal, depending on the type and application of the biosensor. Figure 1 indicates potential bio-receptors and their applications. [Pg.210]


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Optical measurements

Thermal measurements

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