scholarly journals The Amber Project: A Survey of Methods and Inks for the Reproduction of the Color of Translucent Objects

2022 ◽  
Vol 12 (2) ◽  
pp. 793
Author(s):  
Abigail Trujillo-Vazquez ◽  
Harrie Fuller ◽  
Susanne Klein ◽  
Carinna Parraman
Keyword(s):  
Optical Properties ◽  
Light Absorption ◽  
Screen Printing ◽  
Structural Color ◽  
Color Management ◽  
Standard Process ◽  
Color Coordinates ◽  
Black Paper ◽  
Optical Appearance

Unlike regular pigments based on selective light absorption, the so-called “effect pigments″ are based on the phenomena of structural color, or selective reflectance. Structural color has appealing aesthetic qualities, such as angle-dependent hue, and is able to produce lightfast colors. When used as a pigment, however, the gamut of the print is more limited, the color is difficult to measure, and therefore color management and preprint process become challenging. The aim of this paper is to compare the behavior of effect pigments in the processes of lithographic and screen printing with standard pigments used in so-called process inks, and to analyze their optical properties when used on their own or in combination with absorption pigments. An image of amber beads was printed as screen prints and lithographs. Three sets of inks were used: Set one: Standard process inks in the colors cyan, magenta, yellow and black (CMYK); set two: RGB inks formulated with Merck Spectraval™ pearlescent pigments which allow additive red, green, blue printing on a black substrate; and set three: golden inks formulated with pigments from the Merck Iriodin™ and Pyrisma™ effect pigment range. The image was printed on white and black paper. The optical appearance was assessed visually, and spectra and color coordinates were measured.

Recent Advances and the Design Criteria of Metal Sulfide Photocathode and Photoanode for Photoelectrocatalysis

2021 ◽  
Author(s):  
Cui Ying Toe ◽  
Shujie Zhou ◽  
Michael Gunawan ◽  
Xinxin Lu ◽  
Yun Hau Ng ◽  
...  
Keyword(s):  
Optical Properties ◽  
Light Absorption ◽  
Rapid Development ◽  
Metal Sulfide ◽  
Metal Sulfides ◽  
Design Criteria ◽  
Structural And Optical Properties ◽  
Recent Advances ◽  
Favorable Light

Metal sulfides have emerged as promising materials for photoelectrochemical (PEC) applications due to their favorable light absorption ability, tunable structural and optical properties. With the rapid development of PEC systems,...

High electron mobility, controllable magnetism and anomalous light absorption in a monolayered tin mononitride semiconductor

2020 ◽  
Vol 8 (19) ◽  
pp. 6396-6402
Author(s):  
Shuqing Zhang ◽  
Xiaolong Zou
Keyword(s):  
Optical Properties ◽  
Electron Mobility ◽  
Light Absorption ◽  
High Electron ◽  
High Electron Mobility

A monolayered tin mononitride semiconductor with ultrahigh electron mobility, controllable magnetism and outstanding optical properties was predicted.

scholarly journals Hydrothermal Synthesis of Rare-Earth Modified Titania: Influence on Phase Composition, Optical Properties, and Photocatalytic Activity

Materials ◽  
2019 ◽  
Vol 12 (5) ◽  
pp. 713 ◽  
Author(s):  
Nejc Rozman ◽  
David Tobaldi ◽  
Uroš Cvelbar ◽  
Harinarayanan Puliyalil ◽  
João Labrincha ◽  
...  
Keyword(s):  
Optical Properties ◽  
Photocatalytic Activity ◽  
Rare Earth ◽  
Hydrothermal Synthesis ◽  
Rare Earth Elements ◽  
Rare Earths ◽  
Light Absorption ◽  
Pure Tio2 ◽  
X Ray ◽  
Hydroxyl Oxygen

In order to expand the use of titania indoor as well as to increase its overall performance, narrowing the band gap is one of the possibilities to achieve this. Modifying with rare earths (REs) has been relatively unexplored, especially the modification of rutile with rare earth cations. The aim of this study was to find the influence of the modification of TiO2 with rare earths on its structural, optical, morphological, and photocatalytic properties. Titania was synthesized using TiOSO4 as the source of titanium via hydrothermal synthesis procedure at low temperature (200 °C) and modified with selected rare earth elements, namely, Ce, La, and Gd. Structural properties of samples were determined by X-ray powder diffraction (XRD), and the phase ratio was calculated using the Rietveld method. Optical properties were analyzed by ultraviolet and visible light (UV-Vis) spectroscopy. Field emission scanning electron microscope (FE-SEM) was used to determine the morphological properties of samples and to estimate the size of primary crystals. X-ray photoelectron spectroscopy (XPS) was used to determine the chemical bonding properties of samples. Photocatalytic activity of the prepared photocatalysts as well as the titania available on the market (P25) was measured in three different setups, assessing volatile organic compound (VOC) degradation, NOx abatement, and water purification. It was found out that modification with rare earth elements slows down the transformation of anatase and brookite to rutile. Whereas the unmodified sample was composed of only rutile, La- and Gd-modified samples contained anatase and rutile, and Ce-modified samples consisted of anatase, brookite, and rutile. Modification with rare earth metals has turned out to be detrimental to photocatalytic activity. In all cases, pure TiO2 outperformed the modified samples. Cerium-modified TiO2 was the least active sample, despite having a light absorption tail up to 585 nm wavelength. La- and Gd-modified samples did not show a significant shift in light absorption when compared to the pure TiO2 sample. The reason for the lower activity of modified samples was attributed to a greater Ti3+/Ti4+ ratio and a large amount of hydroxyl oxygen found in pure TiO2. All the modified samples had a smaller Ti3+/Ti4+ ratio and less hydroxyl oxygen.

scholarly journals The Effect of Carbon Defects in the Coal–Pyrite Vacancy on the Electronic Structure and Optical Properties: A DFT + U Study

Minerals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 815
Author(s):  
Wei Cheng ◽  
Chen Cheng ◽  
Baolin Ke
Keyword(s):  
Optical Properties ◽  
Electronic Structure ◽  
Absorption Coefficient ◽  
Light Absorption ◽  
Density Functional ◽  
Doping Concentration ◽  
Carbon Doping ◽  
Photovoltaic Materials ◽  
Light Absorption Coefficient ◽  
Carbon Impurities

Pyrite is a mineral often associated with coal in coal seams and is a major source of sulfur in coal. Coal–pyrite is widely distributed, easily available, low-cost, and non-toxic, and has high light absorption coefficient. So, it shows potential for various applications. In this paper, the density-functional theory (DFT + U) is used to construct coal–pyrite with carbon doped in the sulfur and iron vacancies of pyrite. The effects of different carbon defects, different carbon doping concentrations, and different doping distributions in the same concentration on the electronic structure and optical properties of coal–pyrite were studied. The results show that the absorption coefficient and reflectivity of coal–pyrite, when its carbon atom substitutes the iron and sulfur atoms in the sulfur and iron vacancies, are significantly higher than those of the perfect pyrite, indicating that coal–pyrite has potential for application in the field of photovoltaic materials. When carbon is doped in the sulfur vacancy, this impurity state reduces the width of the forbidden band; with the increase in the doping concentration, the width of the forbidden band decreases and the visible-light absorption coefficient increases. The distribution of carbon impurities impacts the band gap but has almost no effect on the light absorption coefficient, complex dielectric function, and reflectivity, indicating that the application of coal–pyrite to photovoltaic materials should mainly consider the carbon doping concentration instead of the distribution of carbon impurities. The research results provide a theoretical reference for the application of coal–pyrite in the field of photoelectric materials.

scholarly journals Attribution of aerosol light absorption to black carbon, brown carbon, and dust in China – interpretations of atmospheric measurements during EAST-AIRE

2009 ◽  
Vol 9 (6) ◽  
pp. 2035-2050 ◽  
Author(s):  
M. Yang ◽  
S. G. Howell ◽  
J. Zhuang ◽  
B. J. Huebert
Keyword(s):  
Optical Properties ◽  
Black Carbon ◽  
Light Absorption ◽  
Northern China ◽  
Wavelength Dependence ◽  
Atmospheric Measurements ◽  
Brown Carbon ◽  
Mass Distributions ◽  
Limit Value ◽  
Light Absorbers

Abstract. Black carbon, brown carbon, and mineral dust are three of the most important light absorbing aerosols. Their optical properties differ greatly and are distinctive functions of the wavelength of light. Most optical instruments that quantify light absorption, however, are unable to distinguish one type of absorbing aerosol from another. It is thus instructive to separate total absorption from these different light absorbers to gain a better understanding of the optical characteristics of each aerosol type. During the EAST-AIRE (East Asian Study of Tropospheric Aerosols: an International Regional Experiment) campaign near Beijing, we measured light scattering using a nephelometer, and light absorption using an aethalometer and a particulate soot absorption photometer. We also measured the total mass concentrations of carbonaceous (elemental and organic carbon) and inorganic particulates, as well as aerosol number and mass distributions. We were able to identify periods during the campaign that were dominated by dust, biomass burning, fresh (industrial) chimney plumes, other coal burning pollution, and relatively clean (background) air for Northern China. Each of these air masses possessed distinct intensive optical properties, including the single scatter albedo and Ångstrom exponents. Based on the wavelength-dependence and particle size distribution, we apportioned total light absorption to black carbon, brown carbon, and dust; their mass absorption efficiencies at 550 nm were estimated to be 9.5, 0.5 (a lower limit value), and 0.03 m2/g, respectively. While agreeing with the common consensus that black carbon is the most important light absorber in the mid-visible, we demonstrated that brown carbon and dust could also cause significant absorption, especially at shorter wavelengths.

scholarly journals Biomass burning and urban emission impacts in the Andes Cordillera region based on in situ measurements from the Chacaltaya observatory, Bolivia (5240 m a.s.l.)

2019 ◽  
Vol 19 (23) ◽  
pp. 14805-14824
Author(s):  
Aurélien Chauvigné ◽  
Diego Aliaga ◽  
Karine Sellegri ◽  
Nadège Montoux ◽  
Radovan Krejci ◽  
...  
Keyword(s):  
Optical Properties ◽  
Biomass Burning ◽  
Light Absorption ◽  
Amazon Basin ◽  
Dry Season ◽  
La Paz ◽  
Extinction Coefficients ◽  
Aerosol Emission ◽  
El Alto ◽  
The Impact

Abstract. This study documents and analyses a 4-year continuous record of aerosol optical properties measured at the Global Atmosphere Watch (GAW) station of Chacaltaya (CHC; 5240 m a.s.l.), in Bolivia. Records of particle light scattering and particle light absorption coefficients are used to investigate how the high Andean Cordillera is affected by both long-range transport and by the fast-growing agglomeration of La Paz–El Alto, located approximately 20 km away and 1.5 km below the sampling site. The extended multi-year record allows us to study the properties of aerosol particles for different air mass types, during wet and dry seasons, also covering periods when the site was affected by biomass burning in the Bolivian lowlands and the Amazon Basin. The absorption, scattering, and extinction coefficients (median annual values of 0.74, 12.14, and 12.96 Mm−1 respectively) show a clear seasonal variation with low values during the wet season (0.57, 7.94, and 8.68 Mm−1 respectively) and higher values during the dry season (0.80, 11.23, and 14.51 Mm−1 respectively). The record is driven by variability at both seasonal and diurnal scales. At a diurnal scale, all records of intensive and extensive aerosol properties show a pronounced variation (daytime maximum, night-time minimum), as a result of the dynamic and convective effects. The particle light absorption, scattering, and extinction coefficients are on average 1.94, 1.49, and 1.55 times higher respectively in the turbulent thermally driven conditions than the more stable conditions, due to more efficient transport from the boundary layer. Retrieved intensive optical properties are significantly different from one season to the other, reflecting the changing aerosol emission sources of aerosol at a larger scale. Using the wavelength dependence of aerosol particle optical properties, we discriminated between contributions from natural (mainly mineral dust) and anthropogenic (mainly biomass burning and urban transport or industries) emissions according to seasons and local circulation. The main sources influencing measurements at CHC are from the urban area of La Paz–El Alto in the Altiplano and from regional biomass burning in the Amazon Basin. Results show a 28 % to 80 % increase in the extinction coefficients during the biomass burning season with respect to the dry season, which is observed in both tropospheric dynamic conditions. From this analysis, long-term observations at CHC provide the first direct evidence of the impact of biomass burning emissions of the Amazon Basin and urban emissions from the La Paz area on atmospheric optical properties at a remote site all the way to the free troposphere.

scholarly journals Structural color printing based on plasmonic metasurfaces of perfect light absorption

2015 ◽  
Vol 5 (1) ◽  
Author(s):  
Fei Cheng ◽  
Jie Gao ◽  
Ting S. Luk ◽  
Xiaodong Yang
Keyword(s):  
Light Absorption ◽  
Structural Color ◽  
Color Printing

Photo-induced linkage isomerization in the gas phase probed by tandem ion mobility and laser spectroscopy

2018 ◽  
Vol 20 (17) ◽  
pp. 12223-12228 ◽  
Author(s):  
Chang Min Choi ◽  
Luke MacAleese ◽  
Philippe Dugourd ◽  
Myoung Choul Choi ◽  
Fabien Chirot
Keyword(s):  
Optical Properties ◽  
Gas Phase ◽  
Laser Spectroscopy ◽  
Ion Mobility ◽  
Light Absorption ◽  
Ruthenium Complexes ◽  
Linkage Isomerization

Ruthenium complexes involving sulfoxide ligands can undergo linkage isomerization upon light absorption, accompanied by dramatic changes in their optical properties.

scholarly journals Wavelength and NO<sub>x</sub> dependent complex refractive index of SOAs generated from the photooxidation of toluene

2012 ◽  
Vol 12 (6) ◽  
pp. 14551-14589 ◽  
Author(s):  
T. Nakayama ◽  
K. Sato ◽  
Y. Matsumi ◽  
T. Imamura ◽  
A. Yamazaki ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Organic Compounds ◽  
Cross Sections ◽  
Light Absorption ◽  
Complex Refractive Index ◽  
Urban Atmosphere ◽  
Radiation Balance ◽  
Limited Information ◽  
K Value

Abstract. Recently, secondary organic aerosols (SOAs) generated from anthropogenic volatile organic compounds have been proposed as a possible source of lightabsorbing organic compounds "brown carbon" in the urban atmosphere. However, the atmospheric importance of these SOAs remains unclear due to limited information about their optical properties. In this study, the complex refractive index (RI, m=n − ki) values at 405, 532, and 781 nm of the SOAs generated during the photooxidation of toluene (toluene-SOAs) under a variety of initial nitrogen oxide (NOx= NO + NO2) conditions were examined by photoacoustic spectroscopy (PAS) and cavity ring down spectroscopy (CRDS). The complex RI values obtained in the present study and reported in the literature indicate that the k value, which represents the light absorption of the toluene-SOAs steeply increased to shorter wavelengths at <405 nm, while the n value gradually increased to shorter wavelengths from 781 to 355 nm. The k values at 405 nm were found to increase from 1.8 × 10−3 to 7.2 × 10−3 with increasing initial NOx concentration from 109 to 571 ppbv. The nitrate to organics ratio of the SOAs determined using a highresolution time-of-flight aerosol mass spectrometer (H-ToF-AMS) also increased with increasing initial NOx concentration. The RI values of the SOAs generated during the photooxidation of 1,3,5-trimethylbenzene in the presence of NOx (1,3,5-TMB-SOAs) were also determined to investigate the influence of the chemical structure of the precursor on the optical properties of the SOAs, and it was found that the light absorption of the 1,3,5-TMB-SOAs is negligible at all of the wavelengths investigated (405, 532, and 781 nm). These results can be reasonably explained by the hypothesis that nitro-aromatic compounds such as nitro-cresols are the major contributors to the light absorption of the toluene-SOAs. Using the obtained RI values, mass absorption cross sections of the toluene-SOAs at 405 and 532 nm were estimated to be 0.08–0.48 and 0.002–0.081 m2 g−1, respectively, under typical conditions in an urban atmosphere during the daytime. These results indicate that light absorption by the SOAs potentially contributes to the radiation balance at ultraviolet wavelengths below ~400 nm, specifically when the mass concentrations of the anthropogenic SOAs are significant compared with those of black carbon particles.

scholarly journals Оптические свойства соединений YFe-=SUB=-2-=/SUB=- и TbFe-=SUB=-2-=/SUB=-

2020 ◽  
Vol 62 (7) ◽  
pp. 1004
Author(s):  
Ю.В. Князев ◽  
Ю.И. Кузьмин
Keyword(s):  
Optical Properties ◽  
Spectral Characteristic ◽  
Wavelength Range ◽  
Optical Conductivity ◽  
Light Absorption ◽  
Electronic States ◽  
Electron Transitions ◽  
Quantum Electron ◽  
Interband Light Absorption ◽  
Conductivity Spectra

Ellipsometric investigation of the optical properties of YFe2 and TbFe2 intermetalic compounds have been carried out in wavelength range of 0.22 –15 μm. A number of electronic and spectral characteristic was determined. Nature of interband light absorption in these materials is discussed on base of comparative analyses of experimental and theoretical optical conductivity spectra. Experimental optical conductivities of the compounds are shown to conform qualitatively to spectra calculated from densities of electronic states in the region of quantum electron transitions.

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