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Optical Nanolithography
Published in Bruce W. Smith, Kazuaki Suzuki, Microlithography, 2020
An optical density (OD) of a masking layer above 2.0 is desirable where target of 3.0 is common, which can be achieved with film thicknesses above about 80 nm. Optical density is a logarithmic measure of opacity, allowing for the scaling of transmitted light with film thickness: OD=−log(1T)
Testing and Spectrometric Characterization of Polymers
Published in Charles E. Carraher, Carraher's Polymer Chemistry, 2017
Colorless materials range from being almost totally transparent to opaque. The opacity is related to the light-scattering process occurring within the material. Incident radiation passes through nonabsorbing, isotropic, optically homogeneous samples with essentially little loss in radiation intensity. Actually, all materials scatter some light. The angular distribution of the scattered light is complex because of the scattering due to micromolecular differences.
Systematic study of phase transformation, wide-to-narrow electronic band transition and optical properties of barium zirconium Oxynitrate: Ab initio calculations
Published in Molecular Physics, 2022
S. S. A. Gillani, Musaddaq Mukhtar, I. Zeba, M. Shakil, Tousif Hussain, Riaz Ahmad
Figure 6(d) shows that the complex refractive index of pure and doped BZO depends on frequency. Traits of material such as transparency or opacity can be explored with the help of refractive index ‘n’. It was evaluated nearly identical for both systems. However, the static refractive index (at 0 eV), the value of ‘n’ for N2-doped BZO is increased a little bit as compared to that for the pure one (from 2.196 to 2.988). The main peak of ‘n’ for the pure and N2-doped BZO is 2.783 which is at 4.26 eV. Specific peak energy values show inverse behavior with respect to each other in absorption and n spectra. K(ω) represents the excitation coefficient, which explains the absorption capacity of a material like . The spectra of absorption and excitation coefficients (Figure 7) match one another. Thus, this can compute the quantity of energy received by BZO. At 2 eV, the extension coefficient is zero and the element has annihilation energy of up to 2 eV.
Maturation processes in glass-ionomer dental cements
Published in Acta Biomaterialia Odontologica Scandinavica, 2018
In principle it is possible to measure opacity in the laboratory. Opacity is not a material property, because it depends on other features of the measurement conditions, notably background colour [32]. It can be quantified in terms of the contrast ratio, Cr defined as: where the R values are measures of reflected light when a specimen of material of defined thickness, in this case 1 mm, is placed on a background surface. R0 is the value when the specimen is on a black background and Rr is the value on a white background. For dental cements, the reflectivity of the white surface used is 0.7 (i.e. 70%) of that of a “pure” white surface, so these values are known as C0.7 values.
Effect of varying 9-Octadecenoic acid (oleic fatty acid) content in biofuel on the performance and emission of a compression ignition engine at varying compression ratio
Published in Biofuels, 2018
P. Dinesha, K. Jagannath, P. Mohanan
The engine exhaust emissions were measured with a smoke meter and an exhaust gas analyzer; OPTRANS 1600(MRU GmbH) & HFA 101 combination measures the opacity of exhaust gas in a measurement chamber of a defined measurement length. The opacity is the extinction of light between light source and receiver, and is a measure of the proportion of particulates present in the exhaust gas. An exhaust gas analyzer – DELTA 1600L (MRU-GmbH) – was used for the measurement of NOX with an electrochemical cell. The details of the uncertainty analysis of the measuring devices and other equipment are given in Table 2.