Lipid oxidation and color changes of goose meat stored under vacuum and modified atmosphere conditions.

PubMed

Orkusz, A; Haraf, G; Okruszek, A; Werenska-Sudnik, M

2017-03-01

The objective of the work was to investigate the color and lipid oxidation changes of goose breast meat packaged in vacuum and modified atmosphere (MA) conditions consisting of 80% O2, 20% CO2, and stored in refrigerated conditions at 4°C. Color stability was monitored by determining total heme pigments concentration; relative concentration of myoglobin, oxymyoglobin, and metmyoglobin; parameters of color L*, a*, b*, and sensory evaluation of the surface color. Lipid stability was measured by determining thiobarbituric acid reactive substances (TBARS). The samples were examined in 24 h after slaughter (unpacked muscles) and on d 4, 7, 9, 11 of storage (muscles packed in vacuum and in MA). Through the time of storage, samples packed in MA had higher TBARS values in comparison to the meat packed in vacuum. For samples packed in two types of atmospheres, the total pigments concentration decreased gradually within 11 d of storage. It was observed that relative metmyoglobin concentration increased whereas relative oxymyoglobin concentration decreased in total heme pigments in the MA stored muscle. The relative concentration of all three myoglobin forms sample packed in vacuum remained unchanged. The color parameters (L*, a*, b*) did not change for 11 d of storage for the vacuum packed meat. The value of the color parameter a* decreased and the value of the color parameters L* and b* increased in the samples packaged in MA. The data prove that if you store goose meat in MA (consisting of 80% O2, 20% CO2) or vacuum, the unchanged surface color is preserved for 9 and 11 day, respectively.Vacuum appears to be a better method as regards the maintaining of lipid stability in goose meat. © 2016 Poultry Science Association Inc.

Stabilizing shallow color centers in diamond created by nitrogen delta-doping using SF{sub 6} plasma treatment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Osterkamp, Christian; Lang, Johannes; Scharpf, Jochen

2015-03-16

Here we report the fabrication of stable, shallow (<5 nm) nitrogen-vacancy (NV) centers in diamond by nitrogen delta doping at the last stage of the chemical vapor deposition growth process. The NVs are stabilized after treating the diamond in SF{sub 6} plasma, otherwise the color centers are not observed, suggesting a strong influence from the surface. X-ray photoelectron spectroscopy measurements show the presence of only fluorine atoms on the surface, in contrast to previous studies, indicating very good surface coverage. We managed to detect hydrogen nuclear magnetic resonance signal from protons in the immersion oil, revealing a depth of the NVsmore » of about 5 nm.« less

Radiochromic film dosimetry for UV-C treatments of apple fruit

USDA-ARS?s Scientific Manuscript database

Radiochromic films were evaluated for their suitability to estimate UV-C doses and dose uniformity on apple fruit surface. Parameters investigated included film type, color changes of the films in response to different UV-C doses, color stability of films, UV-C light intensity, and temperature. In...

The effect of background and illumination on color identification of real, 3D objects.

PubMed

Allred, Sarah R; Olkkonen, Maria

2013-01-01

For the surface reflectance of an object to be a useful cue to object identity, judgments of its color should remain stable across changes in the object's environment. In 2D scenes, there is general consensus that color judgments are much more stable across illumination changes than background changes. Here we investigate whether these findings generalize to real 3D objects. Observers made color matches to cubes as we independently varied both the illumination impinging on the cube and the 3D background of the cube. As in 2D scenes, we found relatively high but imperfect stability of color judgments under an illuminant shift. In contrast to 2D scenes, we found that background had little effect on average color judgments. In addition, variability of color judgments was increased by an illuminant shift and decreased by embedding the cube within a background. Taken together, these results suggest that in real 3D scenes with ample cues to object segregation, the addition of a background may improve stability of color identification.

Efficacy of polishing kits on the surface roughness and color stability of different composite resins.

PubMed

Kocaagaoglu, H; Aslan, T; Gürbulak, A; Albayrak, H; Taşdemir, Z; Gumus, H

2017-05-01

Different polishing kits may have different effects on the composite resin surfaces. The aim of this study was to evaluate the surface roughness and color stability of four different composites which was applied different polishing technique. Thirty specimens were made for each composite resin group (nanohybrid, GrandioSo-GS; nanohybrid, Clearfil Majesty Esthetic-CME; hybrid, Valux Plus-VP; micro-hybrid, Ruby Comp-RC; [15 mm in diameter and 2 mm height]), with the different monomer composition and particle size from a total of 120 specimens. Each composite group was divided into three subgroups (n = 10). The first subgroup of the each composite subgroups served as control (C) and had no surface treatment. The second subgroup of the each composite resin groups was polished with finishing discs (Bisco Finishing Discs; Bisco Inc., Schaumburg, IL, USA). The third subgroup of the each composite resin was polished with polishing wheel (Enhance and PoGo, Dentsply, Konstanz, Germany). The surface roughness and the color differences measurement of the specimens were made and recorded. The data were compared using Kruskal-Wallis test, and regression analysis was used in order to examine the correlation between surface roughness and color differences of the specimens (α = 0.05). The Kruskal-Wallis test indicated significant difference among the composite resins in terms of ΔE (P < 0.05), and there was no statistically significant difference among composite resins in terms of surface roughness (P > 0.05). Result of the regression analysis indicated statistically significant correlation between Ra and ΔE values (P < 0.05, r2 = 0.74). The findings of the present study have clinical relevance in the choice of polishing kits used.

Considerations Regarding the Optical Properties of the Composite Resin Restorative Materials

PubMed Central

Manolea, H.; Râcă, R.; Coleş, Evantia; Preotu, Gabriela; Mărăşescu, P.

2011-01-01

The purpose of this study has been to investigate the effects of certain substances frequently used in alimentation on the color stability of the composite resin restorative materials. The research hypothesis was that color stability of the composite resin is affected by the type of composite material used and by the polishing procedure. 14 samples of 5X15X2mm have been prepared from seven universal light curing restorative composite resins. The materials have manipulated and cured using LA 500 Blue Light lamp. A first color determination was done before the introduction of the samples in the dyeing agent with the help of an Easy Shade device. The samples have been splited into two lots each with seven samples. The samples from the first lot have been sectioned into three equal segments. The samples from the second lot have also been sectioned into three equal segments, and in addition to the previous group, their exterior surfaces were processed with a diamond burr. For each type of composite we have introduced a sample in one of the three chosen dyes: red alimentary colorant, coffee and red wine. The color of the samples has been determined again using the Vita Easy Shade device. From clinical point of view the results of this study shows that there are three important factors that matter when we talk about durable aesthetic results: the type of composite resin used for the restoration, the finishing and polishing procedures and the pacients’ alimentation habits. The composite resins with a good representation of the anorganic structure are easier to be polished, therefore they have only slight color modifications. Using plastic matrixes for shaping the exterior surface of the restoration is the best solution for obtaining a very smooth surface. The most significant color modifications have been done by the red wine. Coffee and to a smaller extent the red alimentary colorant have modified the color of the restoration material in a smaller degree. PMID:24778835

Bleaching agent action on color stability, surface roughness and microhardness of composites submitted to accelerated artificial aging.

PubMed

Rattacaso, Raphael Mendes Bezerra; da Fonseca Roberti Garcia, Lucas; Aguilar, Fabiano Gamero; Consani, Simonides; de Carvalho Panzeri Pires-de-Souza, Fernanda

2011-04-01

The purpose of this study was to evaluate the bleaching agent action on color stability, surface roughness and microhardness of composites (Charisma, Filtek Supreme and Heliomolar - A2) submitted to accelerated artificial aging (AAA). A Teflon matrix (12 x 2 mm) was used to fabricate 18 specimens (n=6) which, after polishing (Sof-Lex), were submitted to initial color reading (ΔE), Knoop microhardness (KHN) (50 g/15 s load) and roughness (R(a)) (cut-off 0.25 mm) tests. Afterwards, the samples were submitted to AAA for 384 hours and new color, microhardness and roughness readings were performed. After this, the samples were submitted to daily application (4 weeks) of 16% Carbamide Peroxide (NiteWhite ACP) for 8 hours and kept in artificial saliva for 16 hours. New color, microhardness and roughness readings were made at the end of the cycle, and 15 days after bleaching. Comparison of the ΔE means (2-way ANOVA, Bonferroni, P<.05) indicated clinically unacceptable color alteration for all composites after AAA, but without significant difference. Statistically significant increase in the KHN values after AAA was observed, but without significant alterations 15 days after bleaching. For R(a) there was no statistically significant difference after AAA and 15 days after bleaching. The alterations promoted by the bleaching agent and AAA are material dependent.

Effect of Children's Drinks on Color Stability of Different Dental Composites: An in vitro Study.

PubMed

Habib, Ahmed Nour El-Din Ahmed; Abdelmoniem, Soad Abdelmoniem; Mahmoud, Sara Ahmed

To assess the effect of four different children's drinks on color stability of resin dental composites. A total of one hundred and twenty specimens were prepared from Grandio SO, Filtek Z350 XT and Filtek Z250 XT (forty specimens each). Specimens were thermocycled, then each group was further subdivided into four subgroups (n=10) according to the immersion media which were chocolate milk, mango juice, orange fizzy drink, and water (control). The initial color parameters of each specimen were recorded before immersion (baseline) and color change values were recorded three and seven days after immersion in each solution using a digital spectrophotometer. Atomic force microscope was used to measure the surface roughness in randomly selected samples after one week immersion in children's drinks. All the children's drinks produced color changes in the examined resin dental composites, yet there was no statistical significant difference between the effects of tested drinks on the color changes (mean ΔE) of the three different dental composites (P>0.05). All tested children's drinks caused clinically unacceptable color changes of the tested resin dental composites. Immersion in chocolate milk and orange fizzy led to the highest color changes in the tested resin dental composites.

Durability of switchable QR code carriers under hydrolytic and photolytic conditions

NASA Astrophysics Data System (ADS)

Ecker, Melanie; Pretsch, Thorsten

2013-09-01

Following a guest diffusion approach, the surface of a shape memory poly(ester urethane) (PEU) was either black or blue colored. Bowtie-shaped quick response (QR) code carriers were then obtained from laser engraving and cutting, before thermo-mechanical functionalization (programming) was applied to stabilize the PEU in a thermo-responsive (switchable) state. The stability of the dye within the polymer surface and long-term functionality of the polymer were investigated against UVA and hydrolytic ageing. Spectrophotometric investigations verified UVA ageing-related color shifts from black to yellow-brownish and blue to petrol-greenish whereas hydrolytically aged samples changed from black to greenish and blue to light blue. In the case of UVA ageing, color changes were accompanied by dye decolorization, whereas hydrolytic ageing led to contrast declines due to dye diffusion. The Michelson contrast could be identified as an effective tool to follow ageing-related contrast changes between surface-dyed and laser-ablated (undyed) polymer regions. As soon as the Michelson contrast fell below a crucial value of 0.1 due to ageing, the QR code was no longer decipherable with a scanning device. Remarkably, the PEU information carrier base material could even then be adequately fixed and recovered. Hence, the surface contrast turned out to be the decisive parameter for QR code carrier applicability.

Effect of Salivary pH on Color Stability of Different Flowable Composites - A Prospective In-vitro Study.

PubMed

Batra, Renu; Kataria, Pratik; Kapoor, Sonali

2016-10-01

Scientifically and clinically there has been lot of development in the field of aesthetic dentistry. However, there is limited or restricted information regarding the color stability of flowable composite materials. The aim of this study was to evaluate the spectrophotometric color stability of three different flowable composite materials with respect to three different pH of saliva. The study included 90 different samples. Thirty samples in each composite group; (Group A: G-aenial universal flo; Group B: Z 350 XT flowable; Group C: Esthet x flow). All samples from each group were immersed in distilled water for 24 hours. Total color difference (ΔE) was recorded for each sample. After this 10 samples from each group were respectively immersed in 6.5, 7 and 7.5 pH of artificial saliva. All samples were kept in dark room for seven days and then ΔE for each sample was recorded and was compared to previous recorded ΔE for the same sample. Maximum color change was seen irrespective of material in 6.5 pH of saliva. G-aenial universal flo showed least change irrespective of pH of saliva. Thus, the present study reveals that acidic pH level affects the coloration of composite resins by affecting the surface integrity and as reported in previous studies, various coloring agents in beverages and other dietary components assists the process due to absorption of these coloring substances into the resin matrix.

Surface Color Perception and Equivalent Illumination Models

PubMed Central

Brainard, David H.; Maloney, Laurence T.

2011-01-01

Vision provides information about the properties and identity of objects. The ease with which we make such judgments belies the difficulty of the information-processing task that accomplishes it. In the case of object color, retinal information about object reflectance is confounded with information about the illumination as well as about the object’s shape and pose. Because of these factors, there is no obvious rule that allows transformation of the retinal images of an object to a color representation that depends primarily on the object’s surface reflectance properties. Despite the difficulty of this task, however, under many circumstances object color appearance is remarkably stable across scenes in which the object is viewed. Here we review experiments and theory that aim to understand how the visual system stabilizes the color appearance of object surfaces. Our emphasis is on a class of models derived from explicit analysis of the computational problem of estimating the physical properties of illuminants and surfaces from the information available in the retinal image and experiments that test these models. We argue that this approach has considerable promise for allowing generalization from simplified laboratory experiments to richer scenes that more closely approximate natural viewing. PMID:21536727

Effect of various teas on color stability of resin composites.

PubMed

Dinç Ata, Gül; Gokay, Osman; Müjdeci, Arzu; Kivrak, Tugba Congara; Mokhtari Tavana, Armin

2017-12-01

To investigate the effect of various teas on color stability of resin composites. Two methacrylate-based (Arabesk Top, Grandio) and a silorane-based (Filtek Silorane) resin composites were used. 110 cylindrical samples of each resin composite were prepared (2 mm thickness and 8 mm diameter), polished and stored in distilled water (37°C for 24 hours). They were randomly divided into 11 groups (n= 10) and color measurements were taken. Then the samples were immersed in tap water (control), a black tea, a green tea or one of the eight herbal-fruit teas (37°C for 1 week) and subsequently subjected to the final color measurements. The color change of samples (ΔE*) was calculated, data were subjected to two-way ANOVA and Tukey's HSD tests. Teas, resin composites and their interactions were significant (P= 0.000). All the teas and control caused color changes in all three resin composites. Rosehip tea caused the most color changes, while tap water showed the least in all resin composites. Arabesk Top had the most staining potential in all the teas and control, whereas Filtek Silorane was the most stain resistant except Grandio immersed in sage tea. Color stability of all resin composites used were affected from both structure of resin materials and constituents of teas used. All resin composites were susceptible to staining by all teas especially rosehip tea. Arabesk Top composite showed the greatest color susceptibility in all teas and Filtek Silorane the least with one exception. Color of resin composites can be negatively affected from teas consumed. Clinicians should advise patients that drinking different kind of teas could intensify surface staining of resin based restorations.

Influence of Different Types of Resin Luting Agents on Color Stability of Ceramic Laminate Veneers Subjected to Accelerated Artificial Aging.

PubMed

Silami, Francisca Daniele Jardilino; Tonani, Rafaella; Alandia-Román, Carla Cecilia; Pires-de-Souza, Fernanda de Carvalho Panzeri

2016-01-01

The aim of this study was to evaluate the influence of accelerated aging (AAA) on the color stability of resin cements for bonding ceramic laminate veneers of different thicknesses. The occlusal surfaces of 80 healthy human molars were flattened. Ceramic laminate veneers (IPS e-max Ceram) of two thicknesses (0.5 and 1.0 mm) were bonded with three types of luting agents: light-cured, conventional dual and self-adhesive dual cement. Teeth without restorations and cement samples (0.5 mm) were used as control. After initial color evaluations, the samples were subjected to AAA for 580 h. After this, new color readouts were made, and the color stability (ΔE) and luminosity (ΔL) data were analyzed. The greatest color changes (p<0.05) occurred when 0.5 mm veneers were fixed with light-cured cement and the lowest when 1.0 mm veneers were fixed with conventional dual cement. There was no influence of the restoration thickness when the self-adhesive dual cement was used. When veneers were compared with the control groups, it was verified that the cement samples presented the greatest alterations (p<0.05) in comparison with both substrates and restored teeth. Therefore, it was concluded that the thickness of the restoration influences color and luminosity changes for conventional dual and light-cured cements. The changes in self-adhesive cement do not depend on restoration thickness.

Quantum computing with Majorana fermion codes

NASA Astrophysics Data System (ADS)

Litinski, Daniel; von Oppen, Felix

2018-05-01

We establish a unified framework for Majorana-based fault-tolerant quantum computation with Majorana surface codes and Majorana color codes. All logical Clifford gates are implemented with zero-time overhead. This is done by introducing a protocol for Pauli product measurements with tetrons and hexons which only requires local 4-Majorana parity measurements. An analogous protocol is used in the fault-tolerant setting, where tetrons and hexons are replaced by Majorana surface code patches, and parity measurements are replaced by lattice surgery, still only requiring local few-Majorana parity measurements. To this end, we discuss twist defects in Majorana fermion surface codes and adapt the technique of twist-based lattice surgery to fermionic codes. Moreover, we propose a family of codes that we refer to as Majorana color codes, which are obtained by concatenating Majorana surface codes with small Majorana fermion codes. Majorana surface and color codes can be used to decrease the space overhead and stabilizer weight compared to their bosonic counterparts.

Effects of the peracetic acid and sodium hypochlorite on the colour stability and surface roughness of the denture base acrylic resins polymerised by microwave and water bath methods.

PubMed

Fernandes, Flavio H C N; Orsi, Iara A; Villabona, Camilo A

2013-03-01

This study evaluated the surface roughness (Ra) and color stability of acrylic resin colors (Lucitone 550, QC-20 and Vipi-Wave) used for fabricating bases for complete, removable dentures, overdentures and prosthetic protocol after immersion in chemical disinfectants (1% sodium hypochlorite and 2% peracetic acid) for 30 and 60 minutes. Sixty specimens were made of each commercial brand of resin composite, and divided into 2 groups according to the chemical disinfectants. Specimens had undergone the finishing and polishing procedures, the initial color and roughness measurements were taken (t=0), and after this, ten test specimens of each commercial brand of resin composite were immersed in sodium hypochlorite and ten in peracetic acid, for 30 and 60 minutes, with measurements being taken after each immersion period. These data were submitted to statistical analysis. There was evidence of an increase in Ra after 30 minutes immersion in the disinfectants in all the resins, with QC-20 presenting the highest Ra values, and Vipi-Wave the lowest. After 60 minutes immersion in the disinfectants all the resins presented statistically significant color alteration. Disinfection with 1% sodium hypochlorite and peracetic acid altered the properties of roughness and color of the resins. © 2012 The Gerodontology Society and John Wiley & Sons A/S.

Gold Nanorods as Surface-Enhanced Raman Spectroscopy Substrates for Rapid and Sensitive Analysis of Allura Red and Sunset Yellow in Beverages.

PubMed

Ou, Yiming; Wang, Xiaohui; Lai, Keqiang; Huang, Yiqun; Rasco, Barbara A; Fan, Yuxia

2018-03-21

Synthetic colorants in food can be a potential threat to human health. In this study, surface-enhanced Raman spectroscopy (SERS) coupled with gold nanorods as substrates is proposed to analyze allura red and sunset yellow in beverages. The gold nanorods with different aspect ratios were synthesized, and their long-term stability, SERS activity, and the effect of the different salts on the SERS signal were investigated. The results demonstrate that gold nanorods have a satisfactory stability (stored up to 28 days). SERS coupled with gold nanorods exhibit stronger sensitivity. MgSO 4 was chosen to improve the SERS signal of sunset yellow, and no salts could enhance the SERS signal of allura red. The lowest concentration was 0.10 mg/L for both colorant standard solutions. The successful prediction results using SERS were much closer to those obtained by high-performance liquid chromatography for the sample in beverages. SERS combined with gold nanorods shows potential for analyzing food colorants and other food additives as a rapid, convenient, and sensitive method.

Effect of glucuronosylation on anthocyanin color stability.

PubMed

Osmani, Sarah Anne; Hansen, Esben Halkjaer; Malien-Aubert, Céline; Olsen, Carl-Erik; Bak, Søren; Møller, Birger Lindberg

2009-04-22

The effect of glucuronosylation on the color stability of anthocyanins was investigated using glucuronosylated anthocyanins isolated from the flower petals of the red daisy (Bellis perennis) or obtained by enzymatic in vitro synthesis using heterologously expressed red daisy glucuronosyltransferase BpUGT94B1. Color stability toward light and heat stress was assessed by monitoring CIELAB color coordinates and stability at pH 7.0 by A(550). Cyanidin-3-O-2''-O-glucuronosylglucoside showed improved color stability in response to light compared to both cyanidin 3-O-glucoside and cyanidin 3-O-2''-O-diglucoside. A similar increase in color stability was not observed following heat treatment. Glucuronosylation did not increase the stability of anthocyanins at pH 7.0 as determined by A(550). To test for a possible effect of glucuronosylation on the color stability of anthocyanins in plant extracts used for food coloration, an elderberry (Sambucus nigra) extract was glucuronosylated in vitro. Glucuronosylation of approximately 50% of total anthocyanins proceeded fast and resulted in increased color stability in response to both heat and light. The data show that glucuronosylation may be used to stabilize industrially used extracts of natural colorants.

Surface gloss and color perception of 3D objects.

PubMed

Xiao, Bei; Brainard, David H

2008-01-01

Two experiments explore the color perception of objects in complex scenes. The first experiment examines the color perception of objects across variation in surface gloss. Observers adjusted the color appearance of a matte sphere to match that of a test sphere. Across conditions we varied the body color and glossiness of the test sphere. The data indicate that observers do not simply match the average light reflected from the test. Indeed, the visual system compensates for the physical effect of varying the gloss, so that appearance is stabilized relative to what is predicted by the spatial average. The second experiment examines how people perceive color across locations on an object. We replaced the test sphere with a soccer ball that had one of its hexagonal faces colored. Observers were asked to adjust the match sphere have the same color appearance as this test patch. The test patch could be located at either an upper or lower location on the soccer ball. In addition, we varied the surface gloss of the entire soccer ball (including the test patch). The data show that there is an effect of test patch location on observers' color matching, but this effect is small compared to the physical change in the average light reflected from the test patch across the two locations. In addition, the effect of glossy highlights on the color appearance of the test patch was consistent with the results from Experiment 1.

Surface gloss and color perception of 3D objects

PubMed Central

Xiao, Bei; Brainard, David H.

2008-01-01

Two experiments explore the color perception of objects in complex scenes. The first experiment examines the color perception of objects across variation in surface gloss. Observers adjusted the color appearance of a matte sphere to match that of a test sphere. Across conditions we varied the body color and glossiness of the test sphere. The data indicate that observers do not simply match the average light reflected from the test. Indeed, the visual system compensates for the physical effect of varying the gloss, so that appearance is stabilized relative to what is predicted by the spatial average. The second experiment examines how people perceive color across locations on an object. We replaced the test sphere with a soccer ball that had one of its hexagonal faces colored. Observers were asked to adjust the match sphere have the same color appearance as this test patch. The test patch could be located at either an upper or lower location on the soccer ball. In addition, we varied the surface gloss of the entire soccer ball (including the test patch). The data show that there is an effect of test patch location on observers’ color matching, but this effect is small compared to the physical change in the average light reflected from the test patch across the two locations. In addition, the effect of glossy highlights on the color appearance of the test patch was consistent with the results from Experiment 1. PMID:18598406

Effects of lactate and modified atmospheric packaging on premature browning in cooked ground beef patties.

PubMed

Mancini, R A; Ramanathan, R; Suman, S P; Konda, M K R; Joseph, P; Dady, G A; Naveena, B M; López-López, I

2010-06-01

Our objectives were to determine the effects of lactate and modified atmosphere packaging on raw surface color, lipid oxidation, and internal cooked color of ground beef patties. Eight chubs (85% lean) were divided in half and each half was either assigned to the control (no lactate) or mixed with 2.5% lactate (w/w). Following treatment, patties were prepared and packaged in either vacuum, PVC (atmospheric oxygen level), high-oxygen (80% O(2)+20% CO(2)), or 0.4% CO (30% CO(2)+69.6% N(2)) and stored for 0, 2, or 4days at 2 degrees C. After storage, raw surface color and lipid oxidation were measured and patties were cooked to either 66 degrees C or 71 degrees C. Lactate improved (p<0.05) color stability of PVC, high-oxygen, and vacuum packaged raw patties, but had no effect (p>0.05) on the a * values and visual color scores of patties in 0.4% CO. Lactate decreased (p<0.05) lipid oxidation in all packaging atmospheres. Nevertheless, high-oxygen and PVC-packaged patties had more (p<0.05) lipid oxidation than patties in CO and vacuum. Lactate had no effect (p>0.05) on premature browning, whereas patties packaged in high-oxygen demonstrated premature browning. Conversely, cooked patties in 0.4% CO and vacuum were more red (p<0.05) than both high-oxygen and PVC-packaged patties. Although lactate improved raw color stability, it did not minimize premature browning in cooked ground beef patties. Copyright 2010 Elsevier Ltd. All rights reserved.

Comparative profiling of sarcoplasmic phosphoproteins in ovine muscle with different color stability.

PubMed

Li, Meng; Li, Zheng; Li, Xin; Xin, Jianzeng; Wang, Ying; Li, Guixia; Wu, Liguo; Shen, Qingwu W; Zhang, Dequan

2018-02-01

The phosphorylation of sarcoplasmic proteins in postmortem muscles was investigated in relationship to color stability in the present study. Although no difference was observed in the global phosphorylation level of sarcoplasmic proteins, difference was determined in the phosphorylation levels of individual protein bands from muscles with different color stability. Correlation analysis and liquid chromatography - tandem mass spectrometry (LC-MS/MS) identification of phosphoproteins showed that most of the color stability-related proteins were glycolytic enzymes. Interestingly, the phosphorylation level of myoglobin was inversely related to meat color stability. As the phosphorylation of myoglobin increased, color stability based on a ∗ value decreased and metMb content increased. In summary, the study revealed that protein phosphorylation might play a role in the regulation of meat color stability probably by regulating glycolysis and the redox stability of myoglobin, which might be affected by the phosphorylation of myoglobin. Copyright © 2017 Elsevier Ltd. All rights reserved.

Simultaneous enhancement of photo- and electroluminescence in white organic light-emitting devices by localized surface plasmons of silver nanoclusters

NASA Astrophysics Data System (ADS)

Yu, Jingting; Zhu, Wenqing; Shi, Guanjie; Zhai, Guangsheng; Qian, Bingjie; Li, Jun

2017-02-01

White organic light-emitting devices (WOLEDs) with enhanced current efficiency and negligible color shifting equipped with an internal color conversion layer (CCL) were fabricated. They were attained by embedding a single layer of silver nanoclusters (SNCs) between the CCL and light-emitting layer (EML). The simultaneous enhancement of the photoluminescence (PL) of the CCL and electroluminescence (EL) of the EML were realized by controlling the thickness and size of the SNCs to match the localized surface plasmon resonance spectrum with the PL spectrum of the CCL and the EL spectrum of the EML. The WOLED with optimal SNCs demonstrated a 25.81% enhancement in current efficiency at 60 mA cm-2 and good color stability over the entire range of current density.

Effect of different surface finishing/polishing procedures on color stability of esthetic restorative materials: A spectrophotometric evaluation

PubMed Central

Beltrami, Riccardo; Ceci, Matteo; De Pani, Gabriele; Vialba, Lodovico; Federico, Ricaldone; Poggio, Claudio; Colombo, Marco

2018-01-01

Objective: To evaluate the color stability of different esthetic restorative materials after surface finishing/polishing with different procedures. Materials and Methods: All materials were polymerized into silicone rubber rings to obtain specimens identical in size. Samples were randomly assigned into four groups (10 specimens of each composite for each group), and they were finished with different procedures: Control group (Group 1), three or two polishers interspersed with diamond grit (Groups 3 and 2, respectively), and one tungsten carbide bur + one polisher interspersed with diamond grit (Group 4). After staining process in coffee, a colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, and 28 days. Shapiro–Wilk test and Kruskal–Wallis analysis of variance were applied to assess significant differences among restorative materials. Means of the different polishing/finishing groups were compared with Scheffe's multiple comparison test at the 0.05 level of significance. Results: In control group, significant lower discolorations were recorded for Essentia, Admira Fusion, and Estelite. After finishing, Filtek Supreme XTE and Ceram.X Universal showed a significantly lower degree of staining. The finishing technique used for Group 4 produced higher color changes. Conclusions: Tungsten carbide burs produced the higher color variations; after finishing, the nanofilled composites showed lower discoloration than nanohybrid ones, and the time of exposure to the staining agent and the polishing/finishing technique influenced the color change. PMID:29657525

Braiding by Majorana tracking and long-range CNOT gates with color codes

NASA Astrophysics Data System (ADS)

Litinski, Daniel; von Oppen, Felix

2017-11-01

Color-code quantum computation seamlessly combines Majorana-based hardware with topological error correction. Specifically, as Clifford gates are transversal in two-dimensional color codes, they enable the use of the Majoranas' non-Abelian statistics for gate operations at the code level. Here, we discuss the implementation of color codes in arrays of Majorana nanowires that avoid branched networks such as T junctions, thereby simplifying their realization. We show that, in such implementations, non-Abelian statistics can be exploited without ever performing physical braiding operations. Physical braiding operations are replaced by Majorana tracking, an entirely software-based protocol which appropriately updates the Majoranas involved in the color-code stabilizer measurements. This approach minimizes the required hardware operations for single-qubit Clifford gates. For Clifford completeness, we combine color codes with surface codes, and use color-to-surface-code lattice surgery for long-range multitarget CNOT gates which have a time overhead that grows only logarithmically with the physical distance separating control and target qubits. With the addition of magic state distillation, our architecture describes a fault-tolerant universal quantum computer in systems such as networks of tetrons, hexons, or Majorana box qubits, but can also be applied to nontopological qubit platforms.

Effect of Heat Treatment on the Physical Properties of Provisional Crowns during Polymerization: An in Vitro Study

PubMed Central

Mei, May L.; So, Sam Y. C.; Li, Hao; Chu, Chun-Hung

2015-01-01

This study concerned the effect of heat treatment during setting on the physical properties of four resin-based provisional restorative materials: Duralay (polymethyl methacrylate), Trim II (polyethyl methacrylate), Luxatemp (bis-acrylic composite), and Protemp 4 (bis-acrylic composite). Specimens were prepared at 23, 37, or 60 °C for evaluation of flexural strength, surface roughness, color change and marginal discrepancy. Flexural strength was determined by a three-point bending test. Surface profile was studied using atomic force microscopy. Color change was evaluated by comparing the color of the materials before and after placement in coffee. A travelling microscope helped prepare standardized crowns for assessment of marginal discrepancy. Flexural strength of all tested materials cured at 23 °C or 37 °C did not significantly change. The surface roughness and marginal discrepancy of the materials increased at 60 °C curing temperature. Marginal discrepancies, color stability, and other physical properties of materials cured at 23 °C or 37 °C did not significantly change. Flexural strength of certain provisional materials cured at 60 °C increased, but there was also an increase in surface roughness and marginal discrepancy. PMID:28788031

Effect of nanofillers' size on surface properties after toothbrush abrasion.

PubMed

Cavalcante, Larissa M; Masouras, Konstantinos; Watts, David C; Pimenta, Luiz A; Silikas, Nick

2009-02-01

To investigate the effect of filler-particle size of experimental and commercial resin composites, undergoing toothbrush abrasion, on three surface properties: surface roughness (SR), surface gloss (G) and color stability (CS). Four model (Ivoclar/Vivadent) and one commercial resin composite (Tokuyama) with varying filler-size from 100-1000 nm were examined. Six discs (10 mm x 2 mm) from each product were prepared and mechanically polished. The samples were then submitted to 20,000 brushing strokes in a toothbrush abrasion machine. SR parameters (Ra, Rt and RSm), G, and CS were measured before and after toothbrush abrasion. Changes in SR and G were analyzed by 2-way ANOVA, with Bonferroni post hoc test. CS values were submitted to one-way ANOVA and Bonferroni post hoc test (alpha=0.05). Initial G values ranged between 73-87 gloss units (GU) and were reduced after toothbrush abrasion to a range of 8-64 GU. Toothbrush abrasion resulted in significant modifications in SR and G amongst the materials tested, attributed to filler sizes. There was statistically significant difference in color (delta E* ranged from 0.38-0.88). Filler size did not affect color stability. Toothbrush abrasion resulted in rougher and matte surfaces for all materials tested. Although the individual differences in surface roughness among filler sizes were not always significant, the correlation showed a trend that larger filler sizes resulted in higher surface roughness after abrasion for the SR parameters Ra and Rt (r = 0.95; r = 0.93, respectively). RSm showed an increase after toothbrush abrasion for all resin composites, however no significant correlation was detected (r = 0.21).There was a significant correlation between G and Ra ratios (r = - 0.95).

Resin cement color stability and its influence on the final shade of all-ceramics.

PubMed

Kilinc, Evren; Antonson, Sibel A; Hardigan, Patrick C; Kesercioglu, Atilla

2011-07-01

Adhesive resin cements may go through internal discoloration, which may show-through and affect the appearance of translucent all-ceramic restorations. This in vitro study evaluated the amount of resin cement color change and its effect on the final shade of the all-ceramics. Three different resin cements in both light and dual-cure forms were included in the study (Nexus-2/Kerr; Appeal/Ivoclar Vivadent; Calibra/Dentsply). All resin cements contained veneered (IPS Empress Esthetic, ETC1 shade, 20 mm × 1 mm ingot discs) and uncovered groups (n=10/group), all luted on white backgrounds (acetalpolyoxymethylene/Delrin(®)). Curing was performed according to ISO standards with a calibrated LED curing-light (Flashlite 1401). Samples were stored in 37°C distilled water at dark. Spectrophotometric baseline color measurements (Color Eye 7000A) were performed from the samples' top surfaces at 24h (D65 illuminator). Samples were subjected to 65 h of accelerated ageing (Atlas Ci4000). Further color measurements from the same areas were recorded in CIEL*a*b* coordinates where a ΔE data above 3 was accepted as visible discoloration (OptiviewLite-1.9software). Statistical analysis was performed using a nested random effects model and Tukey's post hoc analysis. Light-cure groups showed better color stability in all three resins but only in Appeal resin cement, the dual-cure group discolored significantly more (p<0.001). More discoloration was recorded on uncovered cement groups that represented the exposed cement at the margins. There was no visible color change (ΔE>3) through the ceramic surface on any veneered group. All resin cements showed varying degrees of discoloration after accelerated ageing however their actual color change was partially masked by the ceramic. Dual-cure resin cements may affect aesthetics on restoration margins if directly exposed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Effect of vitamin C concentration and co-injection with calcium chloride on beef retail display color.

PubMed

Wheeler, T L; Koohmaraie, M; Shackelford, S D

1996-08-01

The objectives of these experiments were to determine 1) the most effective vitamin C concentration to stabilize color of beef cuts during retail display and 2) the effect on color of incorporating vitamin C into a calcium chloride (CaCl2) injection solution. Top round cuts (semimembranosus and adductor) were injected with 5% by weight of a 0, .25, .5, 1, 2, or 4% sodium ascorbate solution (Exp. 1) or a 0, .5, 1, or 1.5% sodium ascorbate solution (Exp. 2). In Exp. 1, vitamin C resulted in more (P < .05) stable lean color during 9 degrees C display, and .5, 1, and 2% vitamin C were most (P < .05) effective. In Exp. 2, all concentrations of vitamin C maintained redder (P < .05) steaks after 3, 5, and 7 d of display than control steaks and had a lower (P < .05) percentage of surface discoloration after 5 and 7 d of display at 1 degree C. Experiment 3 used beef bottom round cuts (biceps femoris) to compare control, vitamin C- (1%), CaCl2-(200 mM) and vitamin C + CaCl2-treated steaks displayed at 1 degree C. Calcium chloride-treated steaks were more (P < .05) brown and had a higher (P < .05) percentage of surface discoloration on d 5 and 7 than control steaks, whereas steaks treated with vitamin C or vitamin C + CaCl2 were more (P < .05) red and had lower (P < .05) discoloration on d 5 and 7 than control steaks. Vitamin C can be injected into beef subprimals to enhance lean color stability and extend retail display life. Vitamin C also can be used in combination with CaCl2 to offset potential color deterioration, after 5 d of display, due to salt-induced oxidation.

Thermal Stability Results of a Fischer-Tropsch Fuel With Various Blends of Aromatic Solution

NASA Technical Reports Server (NTRS)

Lindsey, Jennifer; Klettlinger, Suder

2013-01-01

Fischer-Tropsch (F-T) jet fuel composition differs from petroleum-based, conventional commercial jet fuel because of differences in feedstock and production methodology. F-T fuel typically has a lower aromatic and sulfur content and consists primarily of iso and normal paraffins. The ASTM D3241 specification for Jet Fuel Thermal Oxidation Test (JFTOT) break point testing method was used to test the breakpoint of a baseline commercial grade F-T jet fuel, and various blends of this F-T fuel with an aromatic solution. The goal of this research is to determine the effect of aromatic content on the thermal stability of F-T fuel. The testing completed in this report was supported by the NASA Fundamental Aeronautics Subsonic Fixed Wing Project. Two different aromatic content fuels from Rentech, as well as these fuels with added aromatic blend were analyzed for thermal stability using the JFTOT method. Preliminary results indicate a reduction in thermal stability occurs upon increasing the aromatic content to 10% by adding an aromatic blend to the neat fuel. These results do not specify a failure based on pressure drop, but only on tube color. It is unclear whether tube color correlates to more deposition on the tube surface or not. Further research is necessary in order to determine if these failures are true failures based on tube color. Research using ellipsometry to determine tube deposit thickness rather than color will be continued in follow-up of this study.

Effect of various de-anodizing techniques on the surface stability of non-colored and colored nanoporous AAO films in acidic solution

NASA Astrophysics Data System (ADS)

Awad, Ahmed M.; Shehata, Omnia S.; Heakal, Fakiha El-Taib

2015-12-01

Anodic aluminum oxide (AAO) is well known as an important nanostructured material, and a useful template in the fabrication of nanostructures. Nanoporous anodic alumina (PAA) with high open porosity was prepared by adopting three de-anodizing regimes following the first anodizing step and preceding the second one. The de-anodizing methods include electrolytic etching (EE) and chemical etching using either phosphoric acid (PE) or sodium hydroxide (HE) solutions. Three of the obtained AAO samples were black colored by electrodeposition of copper nanoparticles in their pores. Electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques were used to characterize the electrochemical performance of the two sets of the prepared samples. In general, the data obtained in aggressive aerated 0.5 M HCl solution demonstrated dissimilar behavior for the three prepared samples despite that the second anodizing step was the same for all of them. The data indicated that the resistance and thickness of the inner barrier part of nano-PAA film, are the main controlling factors determining its stability. On the other hand, coloring the film decreased its stability due to the galvanic effect. The difference in the electrochemical behavior of the three colored samples was discussed based on the difference in both the pore size and thickness of the outer porous part of PAA film as supported by SEM, TEM and cross-sectional micrographs. These results can thus contribute for better engineering applications of nanoporous AAO.

Evaluation of mechanical and thermal properties of commonly used denture base resins.

PubMed

Phoenix, Rodney D; Mansueto, Michael A; Ackerman, Neal A; Jones, Robert E

2004-03-01

The purpose of this investigation was to evaluate and compare the mechanical and thermal properties of 6 commonly used polymethyl methacrylate denture base resins. Sorption, solubility, color stability, adaptation, flexural stiffness, and hardness were assessed to determine compliance with ADA Specification No. 12. Thermal assessments were performed using differential scanning calorimetry and dynamic mechanical analysis. Results were assessed using statistical and observational analyses. All materials satisfied ADA requirements for sorption, solubility, and color stability. Adaptation testing indicated that microwave-activated systems provided better adaptation to associated casts than conventional heat-activated resins. According to flexural testing results, microwaveable resins were relatively stiff, while rubber-modified resins were more flexible. Differential scanning calorimetry indicated that microwave-activated systems were more completely polymerized than conventional heat-activated materials. The microwaveable resins displayed better adaptation, greater stiffness, and greater surface hardness than other denture base resins included in this investigation. Elastomeric toughening agents yielded decreased stiffness, decreased surface hardness, and decreased glass transition temperatures.

Wood surface modification by in-situ sol-gel deposition of hybrid inorganic-organic thin films

Treesearch

Mandla A. Tshabalala; Li-Piin Sung

2007-01-01

Interest in the use of nanoparticles of iron, titanium, aluminum, and zinc oxides in transparent coatings for wood is increasing. Such nano-composite coatings have the potential of not only preserving the natural color of the wood, but also stabilizing the wood surface against the combined degradative effects of sunlight and moisture. The nanoparticles can be used as...

LEACHING BOUNDARY MOVEMENT IN SOLIDIFIED/STABILIZED WASTE FORMS

EPA Science Inventory

Investigation of the leaching of cement-based waste forms in acetic acid solutions found that acids attacked the waste form from the surface toward the center. A sharp leaching boundary was identified in every leached sample, using pH color indica- tors. The movement of the leach...

Effects of organic acid-surfactant mixtures on levels of bacteria and beef quality traits

USDA-ARS?s Scientific Manuscript database

Introduction: Organic acid efficacy as an antimicrobial treatment of beef carcass surfaces may be increased through the addition of surfactants. However, the effects of antimicrobial-surfactant mixtures on beef quality traits such as flavor and color stability may make their use unacceptable. Purp...

Towards muscle-specific meat color stability of Chinese Luxi yellow cattle: A proteomic insight into post-mortem storage.

PubMed

Wu, Wei; Yu, Qian-Qian; Fu, Yu; Tian, Xiao-Jing; Jia, Fei; Li, Xing-Min; Dai, Rui-Tong

2016-09-16

Searching for potential predictors of meat color is a challenging task for the meat industry. In this study, the relationship between meat color parameters and the sarcoplasmic proteome of M. longissimuss lumborum (LL) and M. psoas major (PM) from Chinese Luxi yellow cattle during post-mortem storage (0, 5, 10 and 15days) were explored with the aid of the integrated proteomics and bioinformatics approaches. Meat color attributes revealed that LL displayed better color stability than PM during storage. Furthermore, sarcoplasmic proteins of these two muscles were compared between days 5, 10, 15 and day 0. Several proteins were closely correlated with meat color attributes and they were muscle-specific and responsible for the meat color stability at different storage periods. Glycerol-3-phosphate dehydrogenase, fructose-bisphosphate aldolase A isoform, glycogen phosphorylase, peroxiredoxin-2, phosphoglucomutase-1, superoxide dismutase [Cu-Zn], heat shock cognate protein (71kDa) might serve as the candidate predictors of meat color stability during post-mortem storage. In addition, bioinformatics analyses indicated that more proteins were involved in glycolytic metabolism of LL, which contributed to better meat color stability of LL than PM. The present results could provide a proteomic insight into muscle-specific meat color stability of Chinese Luxi yellow cattle during post-mortem storage. Copyright © 2015 Elsevier B.V. All rights reserved.

Effect of 2 Bleaching Agents with a Content of High Concentrated Hydrogen Peroxide on Stained 2 CAD/CAM Blocks and a Nanohybrid Composite Resin: An AFM Evaluation

PubMed Central

Cengiz, Esra

2017-01-01

The aim of this study was to evaluate color stability of 3 restorative materials, discoloration ability of different solutions, efficacy of 2 office bleaching agents, and surface roughness and topography. Sixty specimens for Clearfil Majesty Esthetic (CME), Lava Ultimate (LU), and Vita Enamic (VE) were prepared. They were immersed into 3 staining solutions for 2 weeks and then they were bleached. According to the measured L⁎, a⁎, and b⁎ parameters described by CIELAB system, color changes (ΔE00), translucency parameters (TP), whiteness index values (W⁎), and changes in closeness to pure white (ΔW⁎) were calculated. Then 3 specimens from each group were scanned with an atomic force microscope for surface analysis. After staining, CME groups and control groups of LU and VE showed clinically acceptable color changes (ΔE00 < 1,8). After bleaching, while a reverse effect on color was observed, VE showed the furthest color values to pure white. There was no statistically significant difference between whiteness index values of LU and CME. LU was the most translucent material during the study and TP values of materials showed minimal differences. Most of the VE groups and a control group of LU showed surface roughness (Ra) values higher than critical value for biofilm accumulation (0,2 μm). PMID:28804719

Effect of low-temperature degradation on the mechanical and microstructural properties of tooth-colored 3Y-TZP ceramics.

PubMed

Nakamura, K; Harada, A; Ono, M; Shibasaki, H; Kanno, T; Niwano, Y; Adolfsson, E; Milleding, P; Örtengren, U

2016-01-01

The aim of the present study was to evaluate the effects of low-temperature degradation (LTD) induced by autoclaving on the mechanical and microstructural properties of tooth-colored 3 mol% yttria-stabilized tetragonal zirconia polycrystals (3Y-TZP). In total, 162 disc-shaped 3Y-TZP specimens were prepared. Two-thirds of the specimens were shaded by either the infiltration or powder mixing methods while the remaining specimens were used without coloring. The specimens were autoclaved at 134 °C for 0, 10, and 100 h to induce LTD (n=18 for each group). Chemical compositions were analyzed with X-ray fluorescence spectroscopy. Biaxial flexural strength was measured using a piston-on-three-ball test. The surface fraction and penetration depth of the monoclinic phase were examined using X-ray diffraction and scanning electron microscopy, respectively. The tooth-colored 3Y-TZP specimens contained Fe2O3 and Er2O3 (infiltration technique), and Fe2O3 (powder mixing method) at concentrations of<0.5 wt%. The tooth-colored 3Y-TZP had higher strength than the non-colored material after 100 h of autoclaving. In terms of surface fraction and penetration depth, the generation of monoclinic phase was significantly lower in the tooth-colored 3Y-TZP than in the non-colored material. The tooth-colored 3Y-TZP possessed equivalent biaxial flexural strength to that of the non-colored material and higher resistance to LTD regardless of the coloring technique (infiltration technique or powder mixing method) when the coloring pigments were contained at concentrations used in the present study. Copyright © 2015 Elsevier Ltd. All rights reserved.

Optimization of stabilized leachate treatment using ozone/persulfate in the advanced oxidation process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abu Amr, Salem S.; Aziz, Hamidi Abdul, E-mail: cehamidi@eng.usm.my; Adlan, Mohd Nordin

Highlights: ► Ozone and persulfate reagent (O{sub 3}/S{sub 2}O{sub 8}{sup 2-}) was used to treat stabilized leachate. ► Central composite design (CCD) with response surface methodology (RSM) was applied. ► Operating variables including ozone and persulfate dosage, pH variance, and reaction time. ► Optimum removal of COD, color, and NH{sub 3}–N was 72%, 96%, and 76%, respectively. ► A good value of ozone consumption (OC) obtained with 0.60 (kg O{sub 3}/kg COD). - Abstract: The objective of this study was to investigate the performance of employing persulfate reagent in the advanced oxidation of ozone to treat stabilized landfill leachate inmore » an ozone reactor. A central composite design (CCD) with response surface methodology (RSM) was applied to evaluate the relationships between operating variables, such as ozone and persulfate dosages, pH, and reaction time, to identify the optimum operating conditions. Quadratic models for the following four responses proved to be significant with very low probabilities (<0.0001): COD, color, NH{sub 3}–N, and ozone consumption (OC). The obtained optimum conditions included a reaction time of 210 min, 30 g/m{sup 3} ozone, 1 g/1 g COD{sub 0}/S{sub 2}O{sub 8}{sup 2-} ratio, and pH 10. The experimental results were corresponded well with predicted models (COD, color, and NH{sub 3}–N removal rates of 72%, 96%, and 76%, respectively, and 0.60 (kg O{sub 3}/kg COD OC). The results obtained in the stabilized leachate treatment were compared with those from other treatment processes, such as ozone only and persulfate S{sub 2}O{sub 8}{sup 2-} only, to evaluate its effectiveness. The combined method (i.e., O{sub 3}/S{sub 2}O{sub 8}{sup 2-}) achieved higher removal efficiencies for COD, color, and NH{sub 3}–N compared with other studied applications. Furthermore, the new method is more efficient than ozone/Fenton in advanced oxidation process in the treatment of the same studied leachate.« less

Range and stability of structural colors generated by Morpho-inspired color reflectors.

PubMed

Chung, Kyungjae; Shin, Jung H

2013-05-01

The range and stability of structural colors generated by Morpho-inspired color reflectors are investigated. We find that despite the internal randomness of such structures that gives rise to their Morpho-like angle-independent iridescence, their colors under ambient lighting condition can be predicted by simple transfer-matrix calculations of corresponding planar multilayer structures. By calculating the possible range of colors generated by multilayers of different structures and material combinations using such transfer-matrix methods, we find that low-refractive index multilayers with intrastructure absorption, such as the melanin-containing chitin/air multilayer structure from the Morpho butterflies, can provide not only the most pure structural colors with the largest color gamut, but also the highest stability of color against variations in multilayer structure.

Biochemical and physical factors affecting discoloration characteristics of 19 bovine muscles.

PubMed

McKenna, D R; Mies, P D; Baird, B E; Pfeiffer, K D; Ellebracht, J W; Savell, J W

2005-08-01

Steaks from muscles (n=19 from nine beef carcasses) were evaluated over the course of retail display (0-, 1-, 2-, 3-, 4- or 5-d) for objective measures of discoloration (metmyoglobin, oxymyoglobin, L*-, a*-, and b*-values), reducing ability (metmyoglobin reductase activity (MRA), resistance to induced metmyoglobin formation (RIMF), and nitric oxide metmyoglobin reducing ability (NORA)), oxygen consumption rate (OCR), oxygen penetration depth, myoglobin content, oxidative rancidity, and pH. Muscles were grouped according to objective color measures of discoloration. M. longissimus lumborum, M. longissimus thoracis, M. semitendinosus, and M. tensor fasciae latae were grouped as "high" color stability muscles, M. semimembranosus, M. rectus femoris, and M. vastus lateralis were grouped as "moderate" color stability muscles, M. trapezius, M. gluteus medius, and M. latissimus dorsi were grouped as "intermediate" color stability muscles, M. triceps brachi - long head, M. biceps femoris, M. pectoralis profundus, M. adductor, M. triceps brachi - lateral head, and M. serratus ventralis were grouped as "low" color stability muscles, and M. supraspinatus, M. infraspinatus, and M. psoas major were grouped as "very low" color stability muscles. Generally, muscles of high color stability had high RIMF, nitric oxide reducing ability, and oxygen penetration depth and possessed low OCRs, myoglobin content, and oxidative rancidity. In contrast, muscles of low color stability had high MRA, OCRs, myoglobin content, and oxidative rancidity and low RIMF, NORA, and oxygen penetration depth. Data indicate that discoloration differences between muscles are related to the amount of reducing activity relative to the OCR.

Facile Synthesis of Monodispersed Polysulfide Spheres for Building Structural Colors with High Color Visibility and Broad Viewing Angle.

PubMed

Li, Feihu; Tang, Bingtao; Wu, Suli; Zhang, Shufen

2017-01-01

The synthesis and assembly of monodispersed colloidal spheres are currently the subject of extensive investigation to fabricate artificial structural color materials. However, artificial structural colors from general colloidal crystals still suffer from the low color visibility and strong viewing angle dependence which seriously hinder their practical application in paints, colorimetric sensors, and color displays. Herein, monodispersed polysulfide (PSF) spheres with intrinsic high refractive index (as high as 1.858) and light-absorbing characteristics are designed, synthesized through a facile polycondensation and crosslinking process between sodium disulfide and 1,2,3-trichloropropane. Owing to their high monodispersity, sufficient surface charge, and good dispersion stability, the PSF spheres can be assembled into large-scale and high-quality 3D photonic crystals. More importantly, high structural color visibility and broad viewing angle are easily achieved because the unique features of PSF can remarkably enhance the relative reflectivity and eliminate the disturbance of scattering and background light. The results of this study provide a simple and efficient strategy to create structural colors with high color visibility, which is very important for their practical application. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

The Surface Properties of Teeth Treated with Resin Infiltration or Amorphous Calcium Phosphate

DTIC Science & Technology

2012-05-04

properties of color stability and surface roughness of demineralized enamel treated with resin infiltration (ICON) or with casein phosphopeptide...amorphous calcium phosphate (MI Paste, CPP-ACP). Methods: Fifty human enamel blocks (4 x 4 mm2) were prepared. Each block was treated with 1M HCl (pH...and 5 (see Figure 2). Conclusion: The results of this study do not provide conclusive evidence that the standard of care for enamel

Effects of protein phosphorylation on color stability of ground meat.

PubMed

Li, Meng; Li, Xin; Xin, Jianzeng; Li, Zheng; Li, Guixia; Zhang, Yan; Du, Manting; Shen, Qingwu W; Zhang, Dequan

2017-03-15

The influence of protein phosphorylation on meat color stability was investigated in this study. Phosphatase and protein kinase inhibitors were added to minced ovine Longissimus thoracis et lumborum (LTL) muscle to manipulate the global phosphorylation of sarcoplasmic proteins. The data obtained show that the rate and extent of pH decline, along with lactate accumulation in postmortem muscle, were related to protein phosphorylation. Analysis of meat color and the relative content of myoglobin redox forms revealed that meat color stability was inversely related to the phosphorylation of sarcoplasmic proteins. Thus, this study suggests that protein phosphorylation may be involved in meat color development by regulating glycolysis and the redox stability of myoglobin. Copyright © 2016 Elsevier Ltd. All rights reserved.

Leaching boundary movement in solidified/stabilized waste forms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuang Ye Cheng; Bishop, P.L.

1992-02-01

Investigation of the leaching of cement-based waste forms in acetic acid solutions found that acids attacked the waste form from the surface toward the center. A sharp leaching boundary was identified in every leached sample, using pH color indicators. The movement of the leaching boundary was found to be a single diffusion-controlled process.

Color stability comparison of silicone facial prostheses following disinfection.

PubMed

Goiato, Marcelo Coelho; Pesqueira, Aldiéris Alves; dos Santos, Daniela Micheline; Zavanelli, Adriana Cristina; Ribeiro, Paula do Prado

2009-04-01

The purpose of this study was to evaluate the color stability of two silicones for use in facial prostheses, under the influence of chemical disinfection and storage time. Twenty-eight specimens were obtained half made from Silastic MDX 4-4210 silicone and the other half from Silastic 732 RTV silicone. The specimens were divided into four groups: Silastic 732 RTV and MDX 4-4210 with disinfection three times a week with Efferdent and Sliastic 732 RTV and MDX 4-4210 disinfected with neutral soap. Color stability was analyzed by spectrophotometry, immediately and 2 months after making the specimens. After obtaining the results, ANOVA and Tukey test with 1% reliability were used for statistical analysis. Statistical differences between mean color values were observed. Disinfection with Efferdent did not statistically influence the mean color values. The factors of storage time and disinfection statistically influenced color stability; disinfection acts as a bleaching agent in silicone materials.

Color stability of laboratory glass-fiber-reinforced plastics for esthetic orthodontic wires

PubMed Central

Inami, Toshihiro; Minami, Naomi; Yamaguchi, Masaru; Kasai, Kazutaka

2015-01-01

Objective In our previous study, glass-fiber-reinforced plastics (GFRPs) made from polycarbonate and glass fibers were prepared for esthetic orthodontic wires using pultrusion. These laboratory GFRP wires are more transparent than the commercially available nickel-titanium wire; however, an investigation of the color stability of GFRP during orthodontic treatment is needed. Accordingly, in the present study, the color stability of GFRP was assessed using colorimetry. Methods Preparation of GFRP esthetic round wires (diameter: 0.45 mm [0.018 inch]) using pultrusion was described previously. Here, to investigate how the diameter of fiber reinforcement affects color stability, GFRPs were prepared by incorporating either 13-µm (GFRP-13) or 7-µm glass (GFRP-7) fibers. The color changes of GFRPs after 24 h, and following 1, 2, and 4 weeks of coffee immersion at 37℃, were measured by colorimetry. We evaluated the color stability of GFRPs by two evaluating units: the color difference (ΔE*) and National Bureau of Standards (NBS). Results After immersion, both GFRPs showed almost no visible color change. According to the colorimetry measurements, the ΔE* values of GFRP-13 and GFRP-7 were 0.73-1.16, and 0.62-1.10, respectively. In accordance with NBS units, both GFRPs showed "slight" color changes. As a result, there were no significant differences in the ΔE* values or NBS units for GFRP-13 or GFRP-7. Moreover, for both GFRPs, no significant differences were observed in any of the immersion periods. Conclusions Our findings suggest that the GFRPs will maintain high color stability during orthodontic treatment, and are an attractive prospect as esthetic orthodontic wires. PMID:26023541

Maceration enzymes and mannoproteins: a possible strategy to increase colloidal stability and color extraction in red wines.

PubMed

Guadalupe, Zenaida; Palacios, Antonio; Ayestaran, Belén

2007-06-13

Different strategies were adopted to achieve increases in color stability in Tempranillo wines: (i) addition of maceration enzymes directly to the must, (ii) addition of commercial mannoproteins to the must, and (iii) inoculation of must with yeast overexpressed of mannoproteins. The addition of enzymes favored color extraction, and the wines obtained presented higher values of wine color, color intensity, bisulfite-stable color, and visually enhanced color intensity. The enzyme hydrolytic activity produced an increase in the acid polysaccharide content and polyphenol index and yielded to wines with more astringency, tannin, and length. Added mannoproteins had clearer effects on the analyzed parameters than yeast. Contrary to what may be thought, mannoproteins did not maintain the extracted polyphenols in colloidal dispersion and neither ensured color stability. These compounds clearly modified the gustative structure of the wines, enhancing the sweetness and roundness.

Stability improvement of natural food colors: Impact of amino acid and peptide addition on anthocyanin stability in model beverages.

PubMed

Chung, Cheryl; Rojanasasithara, Thananunt; Mutilangi, William; McClements, David Julian

2017-03-01

Anthocyanins are prone to chemical degradation and color fading in the presence of vitamin C. The potential of three amino acids (l-phenylalanine, l-tyrosine, l-tryptophan) and a polypeptide (ε-poly-l-lysine) in prolonging the color stability of purple carrot anthocyanins (0.025%) in model beverages (0.05% l-ascorbic acid, citric acid, pH 3.0) stored at elevated temperature (40°C/7 days) was examined. In the absence of amino acids or peptides, anthocyanin degraded at first-order reaction rate. Addition of amino acids or peptide (0.1%) increased the color stability of anthocyanins, with the most significant improvement observed for l-tryptophan. The average half-life of anthocyanin color increased from 2 days to 6 days with l-tryptophan addition. Fluorescence quenching measurements revealed that the l-tryptophan interacted with anthocyanins mainly through hydrogen bonding, although some hydrophobic interaction may also have been involved. Overall, this study suggests that amino acid or peptide addition may prolong the color stability of anthocyanin in beverage products. Copyright © 2016 Elsevier Ltd. All rights reserved.

Structural coloration of chitosan-cationized cotton fabric using photonic crystals

NASA Astrophysics Data System (ADS)

Yavuz, G.; Zille, A.; Seventekin, N.; Souto, A. P.

2017-10-01

In this work, poly (styrene-methyl methacrylate-acrylic acid) P(St-MMA-AA) composite nanospheres were deposited onto chitosan-cationized woven cotton fabrics followed by a second layer of chitosan. The deposited photonic crystals (PCs) on the fabrics were evaluated for coating efficiency and resistance, chemical analysis and color variation by optical and SEM microscopy, ATR-FTIR, diffuse reflectance spectroscopy and washing fastness. Chitosan deposition on cotton fabric provided cationic groups on the fiber surface promoting electrostatic interaction with photonic crystals. SEM images of the washed samples indicate that the PCs are firmly coated on the cotton surface only in the chitosan treated sample. The photonic nanospheres show an average diameter of 280 nm and display a face-centered cubic closepacking structure with an average thickness of 10 μm. A further chitosan post-treatment enhances color yield of the samples due to the chitosan transparent covering layer that induce bright reflections where the angles of incidence and reflection are the same. After washing, no photonic crystal can be detected on control fabric surface. However, the sample that received a chitosan post-treatment showed a good washing fastness maintaining a reasonable degree of iridescence. Chitosan fills the spaces between the polymer spheres in the matrix stabilizing the photonic structure. Sizeable variations in lattice spacing will allow color variations using more flexible non-close-packed photonic crystal arrays in chitosan hydrogels matrices.

UV resistance and dimensional stability of wood modified with isopropenyl acetate.

PubMed

Nagarajappa, Giridhar B; Pandey, Krishna K

2016-02-01

Chemical modification of Rubberwood (Hevea brasiliensis Müll.Arg) with isopropenyl acetate (IPA) in the presence of anhydrous aluminum chloride as a catalyst has been carried out under solvent free conditions. The level of modification was estimated by determining the weight percent gain and modified wood was characterized by FTIR-ATR and CP/MAS (13)C NMR spectroscopy. The effect of catalyst concentration on WPG was studied. UV resistance, moisture adsorption and dimensional stability of modified wood were evaluated. UV resistance of modified wood was evaluated by exposing unmodified and modified wood to UV irradiation in a QUV accelerated weathering tester. Unmodified wood showed rapid color changes and degradation of lignin upon exposure to UV light. Chemical modification of wood polymers with IPA was effective in reducing light induced color changes (photo-yellowing) at wood surfaces. In contrast to unmodified wood, modified wood exhibited bleaching. FTIR analysis of modified wood exposed to UV light indicated stabilization of wood polymers against UV degradation. Modified wood showed good dimensional stability and hydrophobicity. Thermogravimetric analysis showed that modification with IPA improved thermal stability of wood. Improved dimensional stability and UV resistance of modified wood indicates IPA as a promising reagent since there is no acid byproduct of reaction as observed in case of other esterification reactions. Copyright © 2015 Elsevier B.V. All rights reserved.

Degradation Potential of Bulk Versus Incrementally Applied and Indirect Composites: Color, Microhardness, and Surface Deterioration.

PubMed

El Gezawi, M; Kaisarly, D; Al-Saleh, H; ArRejaie, A; Al-Harbi, F; Kunzelmann, K H

This study investigated the color stability and microhardness of five composites exposed to four beverages with different pH values. Composite discs were produced (n=10); Filtek Z250 (3M ESPE) and Filtek P90 (3M ESPE) were applied in two layers (2 mm, 20 seconds), and Tetric N-Ceram Bulk Fill (TetricBF, Ivoclar Vivadent) and SonicFill (Kerr) were applied in bulk (4 mm) and then light cured (40 seconds, Ortholux-LED, 1600 mW/cm 2 ). Indirect composite Sinfony (3M ESPE) was applied in two layers (2 mm) and cured (Visio system, 3M ESPE). The specimens were polished and tested for color stability; ΔE was calculated using spectrophotometer readings. Vickers microhardness (50 g, dwell time=45 seconds) was assessed on the top and bottom surfaces at baseline, 40 days of storage, subsequent repolishing, and 60 days of immersion in distilled water (pH=7.0), Coca-Cola (pH=2.3), orange juice (pH=3.75), or anise (pH=8.5) using scanning electron microscopy (SEM). The materials had similar ΔE values (40 days, p>0.05), but TetricBF had a significantly greater ΔE than P90 or SF (40 days). The ΔE was less for P90 and TetricBF than for Z250, SonicFill, and Sinfony (60 days). Repolishing and further immersion significantly affected the ΔE (p<0.05) except for P90. All composites had significantly different top vs bottom baseline microhardnesses. This was insignificant for the Z250/water, P90/orange juice (40 days), and Sinfony groups (40 and 60 days). Immersion produced variable time-dependent deterioration of microhardness in all groups. Multivariate repeated measures analysis of variance with post hoc Bonferroni tests were used to compare the results. ΔE and microhardness changes were significantly inversely correlated at 40 days, but this relationship was insignificant at 60 days (Pearson test). SEM showed degradation (40 days) that worsened (60 days). Bulk-fill composites differ regarding color-stability and top-to-bottom microhardness changes compared with those of other composites. P90 showed better surface degradation resistance. In conclusion, bulk-fill composites are not promising alternatives to incremental and indirect composites regarding biodegradation.

Antioxidant Activity, Total Phenolics Content, Anthocyanin, and Color Stability of Isotonic Model Beverages Colored with Andes Berry (Rubus glaucus Benth) Anthocyanin Powder

PubMed Central

Estupiñan, D.C.; Schwartz, S.J.; Garzón, G.A.

2013-01-01

The stability of anthocyanin (ACN) freeze-dried powders from Andes berry (Rubus glaucus Benth) as affected by storage, addition of maltodextrin as a carrier agent, and illumination was evaluated in isotonic model beverages. The ethanolic ACN extract was freeze dried with and without maltodextrin DE 20. Isotonic model beverages were colored with freeze-dried ACN powder (FDA), freeze-dried ACN powder with maltodextrin (MFDA), and red nr 40. Beverages were stored in the dark and under the effect of illumination. Half life of the ACNs, changes in color, total phenolics content (TPC), and antioxidant activity were analyzed for 71 d. Addition of maltodextrin and absence of light stabilized the color of beverages and improved ACN and TPC stability during storage. The antioxidant activity of the beverages was higher when they were colored with MFDA and highly correlated with ACN content. There was no correlation between antioxidant activity and TPC. It is concluded that addition of maltodextrin DE 20 as a carrier agent during freeze-drying improves the color and stability of nutraceutical antioxidants present in Andes berry extract. This suggests a protective enclosing of ACNs within a maltodextrin matrix with a resulting powder that could serve as a supplement or additive to naturally color and to enhance the antioxidant capacity of isotonic beverages. PMID:21535712

Antioxidant activity, total phenolics content, anthocyanin, and color stability of isotonic model beverages colored with Andes berry (Rubus glaucus Benth) anthocyanin powder.

PubMed

Estupiñan, D C; Schwartz, S J; Garzón, G A

2011-01-01

The stability of anthocyanin (ACN) freeze-dried powders from Andes berry (Rubus glaucus Benth) as affected by storage, addition of maltodextrin as a carrier agent, and illumination was evaluated in isotonic model beverages. The ethanolic ACN extract was freeze dried with and without maltodextrin DE 20. Isotonic model beverages were colored with freeze-dried ACN powder (FDA), freeze-dried ACN powder with maltodextrin (MFDA), and red nr 40. Beverages were stored in the dark and under the effect of illumination. Half life of the ACNs, changes in color, total phenolics content (TPC), and antioxidant activity were analyzed for 71 d. Addition of maltodextrin and absence of light stabilized the color of beverages and improved ACN and TPC stability during storage. The antioxidant activity of the beverages was higher when they were colored with MFDA and highly correlated with ACN content. There was no correlation between antioxidant activity and TPC. It is concluded that addition of maltodextrin DE 20 as a carrier agent during freeze-drying improves the color and stability of nutraceutical antioxidants present in Andes berry extract. This suggests a protective enclosing of ACNs within a maltodextrin matrix with a resulting powder that could serve as a supplement or additive to naturally color and to enhance the antioxidant capacity of isotonic beverages.

Sol-gel modification of wood substrates to retard weathering

Treesearch

Mandla A Tshabalala; Sam Williams

2008-01-01

Wood specimens were treated with sol-gel systems based on metalorganic precursors of silicon (Si), iron (Fe), zirconium (Zr), and titanium (Ti). The effect of these sol-gel systems on weathering properties of wood was investigated. These sol-gel systems were found to have a positive effect on surface color stability and water vapor resistance of the specimens. Under...

Durable antibacterial and cross-linking cotton with colloidal silver nanoparticles and butane tetracarboxylic acid without yellowing.

PubMed

Montazer, Majid; Alimohammadi, Farbod; Shamei, Ali; Rahimi, Mohammad Karim

2012-01-01

Colloidal nano silver was applied on the surface of cotton fabric and stabilized using 1,2,3,4-butanetetracarboxylic acid (BTCA). The two properties of antimicrobial activity and resistance against creasing were imparted to the samples of fabric as a result of the treatment with silver nano colloid and BTCA. The antimicrobial property of samples was evaluated using two pathogenic bacteria including Escherichia coli and Staphylococcus aureus as outstanding barometers in this field. The durability of applied nanoparticles, color variation, wettability and wrinkle recovery angle of the treated samples were investigated employing related credible standards. The presence of nano silver particles on the surface of treated cotton fabric was proved using EDS spectrum as well as the SEM images. Furthermore, the creation of cross-links was confirmed by the means of both ATR-FTIR and Raman spectra. In conclusion, it was observed that BTCA plays a prominent role in stabilizing silver nanoparticle. Besides, Wettability and winkle recovery angle of finished samples decreased and increased, respectively. In addition, it is noteworthy that no obvious color variation was observed. Copyright © 2011 Elsevier B.V. All rights reserved.

Effects of protective resin coating on the surface roughness and color stability of resin-based restorative materials.

PubMed

Bagis, Bora; Tüzüner, Tamer; Turgut, Sedanur; Korkmaz, Fatih Mehmet; Baygın, Özgül; Bağış, Yıldırım Hakan

2014-01-01

The aim of this study was to evaluate the effects of nanofilled protective resin coating (RC) on the surface roughness (Ra) and color stability (ΔE) of resin-based restorative materials (RM) (compomer (C), nanofilled composite (NF), and microhybrid composite (MH)) after being submitted to the ultraviolet aging (UV) method. Thirty-six specimens were prepared (n = 6 for each group). The Ra and (ΔE) values and SEM images were obtained before and after UV. Significant interactions were found among the RM-RC-UV procedures for Ra (P < 0.001). After the specimens were submitted to UV, the Ra values were significantly increased, regardless of the RC procedure (with RC; P < 0.01 for all, without RC; C (P < 0.01), NF (P < 0.001), and MH (P < 0.001)) for each RM. Significant interactions were found between the RM-RC (P < 0.001) procedures for the ΔE values. The ΔE values were increased in each group after applying the RC procedures (P < 0.001). Protective RC usage for RM could result in material-related differences in Ra and ΔE as with used UV method.

Effects of Protective Resin Coating on the Surface Roughness and Color Stability of Resin-Based Restorative Materials

PubMed Central

Tüzüner, Tamer; Korkmaz, Fatih Mehmet; Baygın, Özgül; Bağış, Yıldırım Hakan

2014-01-01

The aim of this study was to evaluate the effects of nanofilled protective resin coating (RC) on the surface roughness (Ra) and color stability (ΔE) of resin-based restorative materials (RM) (compomer (C), nanofilled composite (NF), and microhybrid composite (MH)) after being submitted to the ultraviolet aging (UV) method. Thirty-six specimens were prepared (n = 6 for each group). The Ra and (ΔE) values and SEM images were obtained before and after UV. Significant interactions were found among the RM-RC-UV procedures for Ra (P < 0.001). After the specimens were submitted to UV, the Ra values were significantly increased, regardless of the RC procedure (with RC; P < 0.01 for all, without RC; C (P < 0.01), NF (P < 0.001), and MH (P < 0.001)) for each RM. Significant interactions were found between the RM-RC (P < 0.001) procedures for the ΔE values. The ΔE values were increased in each group after applying the RC procedures (P < 0.001). Protective RC usage for RM could result in material-related differences in Ra and ΔE as with used UV method. PMID:25162066

Integrating tristimulus colorimetry into pharmaceutical development for color selection and physical appearance control: a quality-by-design approach.

PubMed

Hetrick, Evan M; Vannoy, Jeffrey; Montgomery, Laura L; Pack, Brian W

2013-08-01

The color of pharmaceutical dosage forms can be an important aspect of product branding and patient compliance with a dosing regimen. During the development of drug products, it is important to understand the stability of not only the active pharmaceutical ingredient but also the color and appearance of the tablet or capsule. Currently, the most common method to ensure color stability is to conduct a visual test throughout a stability study. This visual test is subjective and can be expensive, especially if there is a failure late in development or after marketing approval. This work describes a series of studies using accelerated conditions (i.e., heat, humidity, and light) and logistic regression analyses that have been developed to determine the relative stability ranking of multiple color coatings early in development to provide an increased probability of technical success on long-term stability studies and to avoid coatings whose visual appearance may change over time. Once this relative stability ranking has been established, the stability advantages can be assessed versus any manufacturing/processing liabilities of the selected coating in order to make a data-driven decision around coating selection. This work reviews the basic fundamentals of colorimetry, followed by the description of a consistent experimental approach to correlate a visual rating with an instrumental measurement (e.g., dE(*) from a colorimeter) to remove the subjectivity from the assessment. This approach represents a novel strategy for establishing a probabilized correlation between the quantitative instrumental color measurement and the visual rating of the same color change. Copyright © 2013 Wiley Periodicals, Inc.

Quantification and analysis of color stability based on thermal transient behavior in white LED lamps.

PubMed

Nisa Khan, M

2017-09-20

We present measurement and analysis of color stability over time for two categories of white LED lamps based on their thermal management scheme, which also affects their transient lumen depreciation. We previously reported that lumen depreciation in LED lamps can be minimized by properly designing the heat sink configuration that allows lamps to reach a thermal equilibrium condition quickly. Although it is well known that lumen depreciation degrades color stability of white light since color coordinates vary with total lumen power by definition, quantification and characterization of color shifts based on thermal transient behavior have not been previously reported in literature for LED lamps. Here we provide experimental data and analysis of transient color shifts for two categories of household LED lamps (from a total of six lamps in two categories) and demonstrate that reaching thermal equilibrium more quickly provides better stability for color rendering, color temperature, and less deviation of color coordinates from the Planckian blackbody locus line, which are all very important characterization parameters of color for white light. We report for the first time that a lamp's color degradation from the turn-on time primarily depends on thermal transient behavior of the semiconductor LED chip, which experiences a wavelength shift as well as a decrease in its dominant wavelength peak value with time, which in turn degrades the phosphor conversion. For the first time, we also provide a comprehensive quantitative analysis that differentiates color degradation due to the heat rise in GaN/GaInN LED chips and subsequently the boards these chips are mounted on-from that caused by phosphor heating in a white LED module. Finally, we briefly discuss why there are some inevitable trade-offs between omnidirectionality and color and luminous output stability in current household LED lamps and what will help eliminate these trade-offs in future lamp designs.

Resistance to abrasion of extrinsic porcelain esthetic characterization techniques.

PubMed

Chi, Woo J; Browning, William; Looney, Stephen; Mackert, J Rodway; Windhorn, Richard J; Rueggeberg, Frederick

2017-01-01

A novel esthetic porcelain characterization technique involves mixing an appropriate amount of ceramic colorants with clear, low-fusing porcelain (LFP), applying the mixture on the external surfaces, and firing the combined components onto the surface of restorations in a porcelain oven. This method may provide better esthetic qualities and toothbrush abrasion resistance compared to the conventional techniques of applying color-corrective porcelain colorants alone, or applying a clear glaze layer over the colorants. However, there is no scientific literature to support this claim. This research evaluated toothbrush abrasion resistance of a novel porcelain esthetic characterization technique by subjecting specimens to various durations of simulated toothbrush abrasion. The results were compared to those obtained using the conventional characterization techniques of colorant application only or colorant followed by placement of a clear over-glaze. Four experimental groups, all of which were a leucite reinforced ceramic of E TC1 (Vita A1) shade, were prepared and fired in a porcelain oven according to the manufacturer's instructions. Group S (stain only) was characterized by application of surface colorants to provide a definitive shade of Vita A3.5. Group GS (glaze over stain) was characterized by application of a layer of glaze over the existing colorant layer as used for Group S. Group SL (stain+LFP) was characterized by application of a mixture of colorants and clear low-fusing add-on porcelain to provide a definitive shade of Vita A3.5. Group C (Control) was used as a control without any surface characterization. The 4 groups were subjected to mechanical toothbrushing using a 1:1 water-to-toothpaste solution for a simulated duration of 32 years of clinical use. The amount of wear was measured at time intervals simulating every 4 years of toothbrushing. These parameters were evaluated longitudinally for all groups as well as compared at similar time points among groups. In this study, the novel external characterization technique (stain+LFP: Group SL) did not significantly enhance the wear resistance against toothbrush abrasion. Instead, the average wear of the applied extrinsic porcelain was 2 to 3 times more than Group S (stain only) and Group GS (glaze over stain). Application of a glaze layer over the colorants (Group GS) showed a significant improvement on wear resistance. Despite its superior physical properties, the leucite reinforced ceramic core (Group C) showed 2 to 4 times more wear when compared with other test groups. A conventional external esthetic characterization technique of applying a glaze layer over the colorants (Group GS) significantly enhanced the surface wear resistance to toothbrush abrasion when compared with other techniques involving application of colorants only (Group S) or mixture of colorant and LFP (Group SL). The underlying core ceramic had significantly less wear resistance compared with all externally characterized specimens. The novel esthetic characterization technique showed more wear and less color stability, and is thus not advocated as the "best" method for surface characterization. Application of a glaze layer provides a more wear-resistant surface from toothbrush abrasion when adjusting or extrinsically characterizing leucite reinforced ceramic restorations. Without the glaze layer, the restoration is subjected to a 2 to 4 times faster rate and amount of wear leading to possible shade mismatch.

Improving Defect-Based Quantum Emitters in Silicon Carbide via Inorganic Passivation.

PubMed

Polking, Mark J; Dibos, Alan M; de Leon, Nathalie P; Park, Hongkun

2018-01-01

Defect-based color centers in wide-bandgap crystalline solids are actively being explored for quantum information science, sensing, and imaging. Unfortunately, the luminescent properties of these emitters are frequently degraded by blinking and photobleaching that arise from poorly passivated host crystal surfaces. Here, a new method for stabilizing the photoluminescence and charge state of color centers based on epitaxial growth of an inorganic passivation layer is presented. Specifically, carbon antisite-vacancy pairs (CAV centers) in 4H-SiC, which serve as single-photon emitters at visible wavelengths, are used as a model system to demonstrate the power of this inorganic passivation scheme. Analysis of CAV centers with scanning confocal microscopy indicates a dramatic improvement in photostability and an enhancement in emission after growth of an epitaxial AlN passivation layer. Permanent, spatially selective control of the defect charge state can also be achieved by exploiting the mismatch in spontaneous polarization at the AlN/SiC interface. These results demonstrate that epitaxial inorganic passivation of defect-based quantum emitters provides a new method for enhancing photostability, emission, and charge state stability of these color centers. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Color profiles and stability of acylated and nonacylated anthocyanins as novel pigment sources in a lipstick model: A viable alternative to synthetic colorants.

PubMed

Westfall, Alexandra; Giusti, Mónica

Cosmetics, such as lipstick, can affect an individual's perception of attractiveness and morale. Consumer concern with the safety of synthetic colorants has made the need for alternative natural color sources increasingly urgent. Our goal was to evaluate the feasibility of anthocyanin (ACN) extracts as colorants in lipstick formulations. Lipstick formulations were colored with ACN-rich materials. Accelerated environmental testing typical of the cosmetic industry were used: incubation at 20°, 37°, and 45°C for 12 weeks and temperature abuse cycles between 20°/37°C or -20°/20°C. Color (CIELab) and total monomeric ACN (pH-differential) changes were monitored to determine shelf stability of the product. All formulations exhibited acceptable color for lipsticks. Shelf stability was determined to exceed 2 year based on the accelerated testing conditions. Formulations containing cyanidin as their main ACN were the most stable (elderberry, purple corn, and purple sweet potato). ACNs could be used as suitable alternatives to synthetic colorants in lipid-based topical formulations.

Influence of light and oxygen on the color stability of five calcium silicate-based materials.

PubMed

Vallés, Marta; Mercadé, Montse; Duran-Sindreu, Fernando; Bourdelande, Jose L; Roig, Miguel

2013-04-01

Difficult handling, long setting time, and potential discoloration are important drawbacks of white mineral trioxide aggregate (WMTA). The development of Biodentine, a recently developed calcium silicate-based material (CSM), has overcome some of these shortcomings; however, there are no available data on its color stability. A previous study showed that WMTA discolors under light irradiation in an oxygen-free environment. The present study evaluated the influence of light irradiation and oxygen on the color stability of 5 CSMs. Fifteen samples of 5 CSMs (ProRoot WMTA, Angelus WMTA, White Portland Cement [PC], PC with bismuth oxide, and Biodentine) were divided into 5 groups. Each group was exposed to different oxygen and light conditions. A spectrophotometer was used to determine the color of each specimen at 0, 120 seconds, and 5 days. Data were analyzed by using analysis of variance and Tukey honestly significant difference test. The materials PC with bismuth oxide, Angelus WMTA, and ProRoot WMTA showed dark discoloration after light irradiation in an oxygen-free environment, which was statistically significantly different from Biodentine and PC. In groups that were exposed to no light irradiation or to an oxygen atmosphere, all materials showed color stability over time, and no significant differences were observed among them. PC and Biodentine maintained color stability in all conditions over time and showed no significant differences. The combination of light and anaerobic conditions (similar to those in clinical situations) results in differences in color of the tested CSMs during a period of 5 days, of which Biodentine and PC demonstrated color stability. Copyright © 2013 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

[Color stability of porcelain-fused-to-titanium restorations after repeated firings].

PubMed

Wu, Xiao-min; Zhou, Zheng

2004-08-01

To study the effect of repeated firings on color of porcelain-fused-to-titanium restorations. Twenty standard porcelain-fused-to-titanium specimens were made with Dentsply DETREY TiBond C3 and Dentaurum rematitan Til. Then they were fired 1, 2, 4, 7, and 10 times. Color measurement was done after each firing. Most of the color parameters had no significant difference after firing except for a* and Hab. All the color difference among groups were smaller than 1.0 (deltaE < 1.0). Repeated firings will not affect the color stability of porcelain-fused-to-titanium restorations.

An in-vitro evaluation of mechanical and esthetic properties of orthodontic sealants

PubMed Central

Premaraj, Thyagaseely Sheela; Rohani, Nima; Covey, David; Premaraj, Sundaralingam; Hua, Yi; Watanabe, Hidehiko

2014-01-01

Objective: To evaluate mechanical and esthetic Properties of two commercially available orthodontic sealants: Opal®Seal (OS) and L.E.D. Pro Seal (PS). Materials and Methods: Discs of each sealant were prepared to test the following properties: Micro hardness, wear resistance and color stability. Samples were randomly selected after the wear test for SEM imaging to analyze surface morphology. Results: OS was significantly harder than PS (P < 0.001). PS was significantly more wear resistant than OS (P < 0.05). PS showed a greater ∆E*ab (increased staining) when placed in wine or coffee showing a significant difference (P < 0.05). SEM showed particle size, shape and distribution were different for PS and OS reflecting the pattern seen on wear surfaces. Conclusion: Both orthodontic sealants are beneficial for protecting enamel. However with better wear properties PS was superior in resisting mechanical stresses. OS was more color stable. PMID:25512729

Accurate chromatic control and color rendering optimization in LED lighting systems using junction temperature feedback

NASA Astrophysics Data System (ADS)

Sisto, Marco Michele; Gauvin, Jonny

2014-09-01

Accurate color control of LED lighting systems is a challenging task: noticeable chromaticity shifts are commonly observed in mixed-color and phosphor converted LEDs due to intensity dimming. Furthermore, the emitted color varies with the LED temperature. We present a novel color control method for tri-chromatic and tetra-chromatic LEDs, which enable to set and maintain the LED emission at a target color, or combination of correlated color temperature (CCT) and intensity. The LED color point is maintained over variations in the LED junctions' temperatures and intensity dimming levels. The method does not require color feedback sensors, so to minimize system complexity and cost, but relies on estimation of the LED junctions' temperatures from the junction voltages. If operated with tetra-chromatic LEDs, the method allows meeting an additional optimization criterion: for example, the maximization of a color rendering metric like the Color Rendering Index (CRI) or the Color Quality Scale (CQS), thus providing a high quality and clarity of colors on the surface illuminated by the LED. We demonstrate the control of a RGBW LED at target D65 white point with CIELAB color difference metric triangle;a,bE < 1 for simultaneous variations of flux from approximately 30 lm to 100 lm and LED heat sink temperature from 25°C to 58°C. In the same conditions, we demonstrate a CCT error <1%. Furthermore, the method allows varying the LED CCT from 5500K to 8000K while maintaining luminance within 1% of target. Further work is ongoing to evaluate the stability of the method over LED aging.

Microencapsulation by freeze-drying of potassium norbixinate and curcumin with maltodextrin: stability, solubility, and food application.

PubMed

Sousdaleff, Mirian; Baesso, Mauro Luciano; Medina Neto, Antonio; Nogueira, Ana Cláudia; Marcolino, Vanessa Aparecida; Matioli, Graciette

2013-01-30

Stability of potassium norbixinate and curcumin by microencapsulation with maltodextrin DE20 and freeze-drying was evaluated as a function of exposition to light, air, different pH, water solubility, and in food applications. The best results were obtained with microencapsulated potassium norbixinate 1:20, which, when vacuum-packed and in the presence of natural light, showed color retention of 78%, while microencapsulated curcumin 1:20 showed color retention of 71%. Differential scanning calorimetry and thermogravimetry provided an indication of interaction between colorants and maltodextrin. Photoacoustic spectroscopy (PAS) showed that free and microencapsulated colorants exhibited high rates of absorption throughout the measured spectral region. This work evidenced that the freeze-drying process is favorable for microencapsulation of curcumin by maltodextrin, providing improved solubility to the microencapsulated colorant. Both microencapsulated colorants showed relevant results for use in a wide range of pH and food applications. The PAS technique was useful for the evaluation of the stability of free and microencapsulated colorants.

Comparative Thermal Degradation Patterns of Natural Yellow Colorants Used in Foods.

PubMed

Giménez, Pedro J; Fernández-López, José A; Angosto, José M; Obón, José M

2015-12-01

There is a great interest in natural yellow colorants due to warnings issued about certain yellow food colorings of synthetic origin. However, no comparative studies have been reported of their thermal stability. For this reason, the thermal stabilities of six natural yellow colorants used in foods--lutein, riboflavin, curcumin, ß-carotene, gardenia yellow and Opuntia betaxanthins--were studied in simple solutions over a temperature range 30-90 °C. Spectral properties and visual color were investigated during 6 h of heat treatment. Visual color was monitored from the CIEL*a*b* parameters. The remaining absorbance at maximum wavelength and the total color difference were used to quantify color degradation. The rate of color degradation increased as the temperature rose. The results showed that the thermal degradation of the colorants followed a first-order reaction kinetics. The reaction rate constants and half-life periods were determined as being central to understanding the color degradation kinetics. The temperature-dependent degradation was adequately modeled on the Arrhenius equation. Activation energies ranged from 3.2 kJmol(-1) (lutein) to 43.7 kJmol(-1) (Opuntia betaxanthins). ß-carotene and lutein exhibited high thermal stability, while betaxanthins and riboflavin degraded rapidly as temperature increased. Gardenia yellow and curcumin were in an intermediate position.

Effects of cold light bleaching on the color stability of composite resins

PubMed Central

Cao, Liqun; Huang, Lijuan; Wu, Meisheng; Wei, Hua; Zhao, Shouliang

2015-01-01

To evaluate the effects of cold light bleaching on the color stability of four restorations using a thermocycling stain challenge. 160 specimens (10 mm in diameter and 2 mm thick) were fabricated from 4 composite resins (Gradia Direct-A, Z350XT, Premisa, and Précis) and divided into 4 subgroups. Color was assessed according to the CIEL*a*b* color scale at baseline, after the first cycle of bleaching, after thermocycling stain challenges, and after the second cycle of bleaching. Mean values were compared using three-way analysis of variance, and multiple comparisons of the mean values were performed using the Tukey-Kramer test. All groups showed significant color changes after stain challenge, the color change was more significant in Gradia Direct and Z350XT than in Premisa and Précis. After the second cycle of bleaching, color mostly recovered to its original values. The color stability of Gradia Direct and Z350XT was inferior to that of Premisa and Précis. The discoloration of composite resin materials can be partly removed after cold light bleaching. PMID:26309549

12-month color stability of enamel, dentine, and enamel-dentine samples after bleaching.

PubMed

Wiegand, Annette; Drebenstedt, Steffi; Roos, Malgorzata; Magalhães, Ana Carolina; Attin, Thomas

2008-12-01

The study aimed to quantify the color regression of enamel (E), dentine (D), and combined enamel-dentine (ED) of differently bleached ED specimens over a period of 12 months in vitro. Two ED samples were obtained from the labial surfaces of bovine teeth and prepared to a standardized thickness with the enamel and dentine layer each 1 mm. The ED samples were distributed on four groups (each n = 80), in which the different bleaching products were applied on enamel (1, Whitestrips; 2, Illuminé 15%; 3, Opalescence Xtra Boost) or dentine surfaces (4, mixture of sodium perborate/distilled water). Eighty ED samples were not bleached (control). Color (L*a*b*) of ED was assessed at baseline, subsequently after bleaching and at 3, 6, and 12 months of storage after bleaching (each 20 samples/group). E and D samples were prepared by removing the dentine or enamel layer of ED samples to allow for separate color analysis. Bleaching resulted in a significant color change (Delta E) of ED specimens. Within the observation period, Delta L but not Delta b declined to baseline. L* values of E and D samples also declined and were not significantly different from control samples after 12 months, while b* values did not decrease to baseline. Generally, no differences between the bleaching agents could be observed. Color change of enamel, dentine, and combined ED of in vitro bleached tooth samples is not stable over time with regard to lightness. However, yellowness did not return to baseline within 1 year.

Color stability and lipid oxidation of broiler breast meat from animals raised on organic versus non-organic production systems.

PubMed

Viana, F M; Canto, A C V C S; Costa-Lima, B R C; Salim, A P A A; Conte-Junior, C A

2017-03-01

The aim of the present research was to evaluate the influence of organic and non-organic production systems on color stability and lipid oxidation of broiler meat Pectoralis major (PM) stored under refrigeration (4°C) for 9 days. PM samples from organic (ORG) and non-organic (NORG) production systems were compared based on physicochemical analyses (instrumental color, myoglobin concentration, metmyoglobin reducing activity (MRA), pH, and lipid oxidation) performed in 4 different trials (n = 4). In general, NORG broilers demonstrated higher (P < 0.05) b* and lipid oxidation values than ORG, whereas ORG samples exhibited increased (P < 0.05) MRA, ratio of reflectance at 630 per 580 nanometers (R 630/580), and a* values. The lower color stability observed in NORG samples can be partly due to lipid oxidation. Therefore, the production system can affect color and lipid stability of broiler breast meat during storage. © 2016 Poultry Science Association Inc.

Optimization of supercritical carbon dioxide treatment for the inactivation of the natural microbial flora in cubed cooked ham.

PubMed

Ferrentino, Giovanna; Balzan, Sara; Spilimbergo, Sara

2013-02-15

This study aims to investigate the effects of supercritical carbon dioxide (SC-CO₂) treatment on the inactivation of the natural microbial flora in cubed cooked ham. Response surface methodology with a central composite design was applied to determine the optimal process conditions and investigate the effect of three independent variables (pressure, temperature and treatment time). Additionally, analyses of texture, pH and color together with a storage study of the product were performed to determine its microbial and qualitative stability. Response surface analysis revealed that 12 MPa, 50 °C, 5 min were the optimal conditions to obtain about 3.0, 1.6, and 2.5 Log(CFU/g) reductions of mesophilic aerobic bacteria, psychrophilic bacteria and lactic acid bacteria respectively. Inactivation to undetectable levels of yeasts and molds and coliforms was also obtained. A storage study of 30 days at 4 °C was carried out on the treated product (12 MPa, 50 °C, 5 min) monitoring microbial growth, pH, texture, and color parameters (L*, a*, b* and ΔE). Microbial loads slightly increased and after 30 days of storage reached the same levels detected in the fresh product. Color parameters (L*, a*, b*) showed slight variations while pH and texture did not change significantly. On the basis of the results obtained, SC-CO₂ can be considered a promising technique to microbiologically stabilize cubed cooked ham and, in general, cut/sliced meat products without affecting its quality attributes. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of time of measurement on the relationship between metmyoglobin reducing activity and oxygen consumption to instrumental measures of beef longissimus color stability

USDA-ARS?s Scientific Manuscript database

The contribution of initial and retained levels of oxygen consumption and reducing capacity to animal variation in color stability were evaluated. Instrumental color values were determined on longissimus thoracis steaks (n=257) during 6 d of display. Oxygen consumption (OC), nitric oxide metmyoglo...

A novel pyrophosphate BaCr2(P2O7)2 as green pigment with high NIR solar reflectance and durable chemical stability

NASA Astrophysics Data System (ADS)

Tao, Zhengxu; Zhang, Wanqi; Huang, Yanlin; Wei, Donglei; Seo, Hyo Jin

2014-08-01

A novel pyrophosphate BaCr2(P2O7)2 was synthesized by the conventional solid-state reaction. The X-ray diffraction (XRD), FTIR spectrum, scanning electron microscopy (SEM) and ultraviolet-visible (UV-Vis) near infrared (NIR) reflectance spectra were applied to characterize the powders. The refractive indexes and nature of the VB and CB were determined. The structure, color properties and application were investigated. The results reveal that the anomalist bodies with smooth surfaces were obtained at 1200 °C with a mean size of 3 μm. A high reflectance peak at 535 nm was observed in the visible region, which is associated with the brilliant and deep green color of this pigment. With all the acids, alkali and deionized water treatment, the polycrystalline pigment BaCr2(P2O7)2 was found to be durable in chemical stability. The significantly high NIR solar reflectance of BaCr2(P2O7)2 is 90.0%, a higher cooling ability, so it has been selected to be tested as cool green pigment in ceramics. Moreover, this novel pyrophosphate pigment has great potential as cool pigment for surface coating applications.

Effect of one-step polishing system on the color stability of nanocomposites.

PubMed

Alawjali, S S; Lui, J L

2013-08-01

This study was to compare the effect of three different one-step polishing systems on the color stability of three different types of nanocomposites after immersion in coffee for one day and seven days and determine which nanocomposite material has the best color stability following polishing with each of the one-step polishing system. The nanocomposites tested were Tetric EvoCeram, Grandio and Herculite Précis. A total of 120 discs (40/nanocomposite, 8mm×2mm) were fabricated. Ten specimens for each nanocomposite cured under Mylar strips served as the control. The other specimens were polished with OptraPol, OneGloss and Occlubrush immersed in coffee (Nescafé) up to seven days. Color measurements were made with a spectrophotometer at baseline and after one and seven days. Two way repeated measure ANOVA, two way ANOVA and Bonferroni tests were used for statistical analyses (P<0.05). The immersion time was a significant factor in the discoloration of the nanocomposites. The effect of three one-step polishing systems on the color stability was also significant. The color change values of the materials cured against Mylar strips were the greatest. The lowest mean color change values were from the Occlubrush polished groups. The effect of the three different types of nanocomposite on the color change was significant. The highest color change values were with Tetric EvoCeram groups. The lowest color change values were with Herculite Précis groups. The color change of nanocomposite resins is affected by the type of composite, polishing procedure and the period of immersion in the staining agent. Copyright © 2012 Elsevier Ltd. All rights reserved.

2013 Early Career Achievement Award--Proteomics of muscle- and species-specificity in meat color stability.

PubMed

Suman, S P; Rentfrow, G; Nair, M N; Joseph, P

2014-03-01

Meat color is the most important quality trait influencing consumer purchase decisions. The interinfluential interactions between myoglobin and biomolecules govern color stability in meat. The advances in proteomics, such as high throughput analytical tools in mass spectrometry, 2-dimensional electrophoresis, and bioinformatics, offer themselves as robust techniques to characterize the proteome basis of muscle- and species-specific meat color phenomena. Differential abundance of chaperones and antioxidant proteins contributes to muscle-specific color stability in beef; the greater abundance of chaperones and antioxidant proteins in color-stable Longissimus lumborum than in color-labile Psoas major protects myoglobin and contributes to superior color stability of beef Longissimus steaks. Lipid oxidation-induced myoglobin oxidation is more critical to beef color than pork color due to the inherent differences in myoglobin chemistry; the number of nucleophilic histidine residues adducted by reactive aldehydes is greater in beef myoglobin than in pork myoglobin. Preferential adduction of secondary products of lipid oxidation to beef myoglobin accelerates metmyoglobin formation at a greater degree than in its pork counterpart. Mass spectrometric investigations revealed that although cherry-red carboxymyoglobin is more stable than oxymyoglobin, both redox forms undergo lipid oxidation-induced oxidation in model systems. The accuracy of mass spectrometry to detect the molecular mass of proteins has been applied to differentiate myoglobins from closely related meat animals, such as goats and sheep or emu and ostrich. In addition, this approach indicated that turkey myoglobin is 350 Da greater in molecular mass than beef myoglobin, and the unique biochemistry of turkey myoglobin could be responsible for its greater thermostability in model systems as well as the pink color defect observed in fully cooked uncured turkey products.

Effect of brushing and thermocycling on the shade and surface roughness of CAD-CAM ceramic restorations.

PubMed

Yuan, Judy Chia-Chun; Barão, Valentim Adelino Ricardo; Wee, Alvin G; Alfaro, Maria F; Afshari, Fatemeh S; Sukotjo, Cortino

2017-09-29

The effects of toothbrushing (B) and thermocycling (TC) on the surface texture of different materials with various fabrication processes have been investigated. However, studies of computer-aided design and computer-aided manufacturing (CAD-CAM) ceramic restorations are limited. The purpose of this in vitro study was to evaluate the effect of B and TC on the color stability and surface roughness of extrinsically characterized and glazed CAD-CAM ceramic restorations. Lithium disilicate CAD ceramic (n=90) and zirconia ceramic (n=90) were studied. All specimens were crystallized/sintered, characterized, and glazed following the manufacturer's recommendation. The specimens were divided into 9 different groups: B, TC, and a combination of B plus TC (B+TC). Brushing was performed at 50 000, 100 000, and 150 000 cycles, simulating an oral environment of 5, 10, and 15 years. Thermocycling was performed at 6000, 12 000, and 18 000 cycles, simulating an oral environment of 5, 10, and 15 years. Brushing plus TC was performed with the combination of the 50 000 cycles of B, then 6000 cycles of TC, and 10 000 cycles of B, then 12 000 cycles of TC, and 15 000 cycles of B, then 18 000 cycles of TC. The color and surface roughness of each specimen were measured before and after all interventions with simulated cycles. Color differences (ΔE) and surface roughness (ΔR a ) data were analyzed using 2-way ANOVA, followed by the least significant difference test (α=.05). The correlation between ΔE and ΔR a was statistically analyzed using the Pearson correlation analysis. Within the lithium disilicate CAD groups, intervention did not result in any significant differences in color change (P>.05). Within the zirconia groups, a 15-year clinical simulation revealed significantly higher ΔE values than a simulated 5-year exposure (P=.017). Increased simulated cycles showed significantly higher R a values for all groups. Within the zirconia groups, B revealed significantly smoother surfaces than TC (P<.001) and B+TC interventions (P<.001). For the zirconia, simulating B+TC for15 years revealed significantly higher R a values than the groups of B+TC for 5 years (P<.001) and B+TC for 10 years (P=.003). No correlation (lithium disilicate CAD, r=.079; P=.462; zirconia, r=.001; P=.989) was found between the color change and surface roughness. For both lithium disilicate CAD and zirconia, color changes were below the selected clinical perceptible threshold (ΔE=2.6) after all intervention and simulated cycles. All mean surface roughness measurements were below 0.2 μm. Generally, the surface of both lithium disilicate CAD and zirconia became rougher. No correlation was found between color difference and surface roughness for either material. Published by Elsevier Inc.

Enhanced color purity of blue OLEDs based on well-design structure

NASA Astrophysics Data System (ADS)

Du, Qianqian; Wang, Wenjun; Li, Shuhong; Wang, Qingru; Xia, Shuzhen; Zhang, Bingyuan; Wang, Minghong; Fan, Quli

2016-09-01

We have fabricated blue organic light-emitting devices (OLEDs) with higher color purity and stability by optimizing the structure of the Glass/ITO/NPB(50 nm)/ BCzVBi (30 nm)/ TPBi (x nm)/Alq3(20 nm)/LiF/Al. The results show that the introducing of hole blocking layer(HBL) TPBi greatly can improve not only the color purity but the color stability, which owe to its higher the Highest Occupied Molecular Orbital (HOMO) energy levels of 6.2 eV. We expect our work will be useful to optimizing the blue OLEDs structure to enhancing the color property.

Effect of different photoinitiators and reducing agents on cure efficiency and color stability of resin-based composites using different LED wavelengths.

PubMed

de Oliveira, Dayane Carvalho Ramos Salles; Rocha, Mateus Garcia; Gatti, Alexandre; Correr, Americo Bortolazzo; Ferracane, Jack Liborio; Sinhoret, Mario Alexandre Coelho

2015-12-01

To evaluate the effect of photoinitiators and reducing agents on cure efficiency and color stability of resin-based composites using different LED wavelengths. Model resin-based composites were associated with diphenyl(2,4,6-trimethylbenzoyl) phosphine oxide (TPO), phenylbis(2,4,6-trimethylbenzoyl) phosphine oxide (BAPO) or camphorquinone (CQ) associated with 2-(dimethylamino) ethyl methacrylate (DMAEMA), ethyl 4-(dimethyamino) benzoate (EDMAB) or 4-(N,N-dimethylamino) phenethyl alcohol (DMPOH). A narrow (Smartlite, Dentisply) and a broad spectrum (Bluephase G2, Ivoclar Vivadent) LEDs were used for photo-activation (20 J/cm(2)). Fourier transform infrared spectroscopy (FT-IR) was used to evaluate the cure efficiency for each composite, and CIELab parameters to evaluated color stability (ΔE00) after aging. The UV-vis absorption spectrophotometric analysis of each photoinitiator and reducing agent was determined. Data were analyzed using two-way ANOVA and Tukey's test for multiple comparisons (α=0.05). Higher cure efficiency was found for type-I photoinitiators photo-activated with a broad spectrum light, and for CQ-systems with a narrow band spectrum light, except when combined with an aliphatic amine (DMAEMA). Also, when combined with aromatic amines (EDMAB and DMPOH), similar cure efficiency with both wavelength LEDs was found. TPO had no cure efficiency when light-cured exclusively with a blue narrowband spectrum. CQ-systems presented higher color stability than type-I photoinitiators, especially when combined with DMPOH. After aging, CQ-based composites became more yellow and BAPO and TPO lighter and less yellow. However, CQ-systems presented higher color stability than type-I photoinitiators, as BAPO- and TPO-, despite their higher cure efficiency when photo-activated with corresponding wavelength range. Color matching is initially important, but color change over time will be one of the major reasons for replacing esthetic restorations; despite the less yellowing of these alternative photoinitiators, camphorquinone presented higher color stability. Copyright © 2015 Elsevier Ltd. All rights reserved.

Chlorophyll extraction from suji leaf (Pleomele angustifolia Roxb.) with ZnCl2 stabilizer.

PubMed

Rahayuningsih, Edia; Pamungkas, Mukmin Sapto; Olvianas, Muhammad; Putera, Andreas Diga Pratama

2018-03-01

Suji ( Pleomele angustifolia Roxb .) leaves are a prominent source of chlorophyll and well-known for their ability to produce green color for food ingredients. However, chlorophyll is suspectible to color degradation at high temperature. Color degradation occurred because porphyrin loses magnesium in its ring and it can be avoided by adding zinc. The aim of this work was to investigate the combined effect of independent variables on chlorophyll extraction process using ZnCl 2 as a stabilizer. Suji leaves were blanched with boiling water for 2 min, Zn-chlorophyll synthesis was done by varying concentration of ZnCl 2 , Zn-chlorophyll extraction with ethanol, and UV-Vis spectrophotometry analysis of the final extracted solutions. A full three-level factorial design under response surface methodology was used to obtain the optimum condition of extraction process. The experimental data were analyzed by analysis of variance and fitted with second order polynomial equation. The coefficient of determination (R 2 ) was found to be 81.99%. The optimum operating conditions were obtained at pH 7, ZnCl 2 concentration of 700 ppm and temperature of 85 °C with desirability value of 1.0000. At the optimum conditions, the total chlorophyll content (TCC) was found to be 47.2975 mg/100 g fresh weight.

Contribution of genetic influences to animal-to-animal variation in myoglobin content and beef lean color stability.

PubMed

King, D A; Shackelford, S D; Kuehn, L A; Kemp, C M; Rodriguez, A B; Thallman, R M; Wheeler, T L

2010-03-01

Longissimus thoracis steaks from steers (n = 464) with 0 to 50% inheritance of Angus, Charolais, Gelbvieh, Hereford, Limousin, Red Angus, and Simmental were evaluated during 6 d of display to assess genetic contributions to color stability. Color space values [CIE L* (lightness), a* (redness), b* (yellowness)], chroma, color change (DeltaE), and surface metmyoglobin (K/S 572/525) were determined on d 0 and 6 of display. Myoglobin concentration was highly heritable (0.85), but ultimate pH was weakly heritable (0.06). Day 0 L* values were moderately heritable (0.24). Variation in metmyoglobin, L*, and DeltaE on d 6 was moderately explained by genetic factors (41, 40, and 29%, respectively). Change during display was moderately heritable for a* (0.31), b* (0.23), chroma (0.35), and surface metmyoglobin (0.29). At the start of display, Angus steaks had greater (P < 0.05) L* values than those from all breeds except Charolais. On d 6, Angus steaks had greater (P < 0.05) L* (50.0) values than Gelbvieh, Hereford, and Simmental steaks (46.1, 44.0, and 44.5, respectively). Day 0 values for a*, b*, chroma, and DeltaE were not affected by breed (P > 0.05). On d 6, a* values were greater (P < 0.05) for Charolais and Limousin steaks (31.1 and 30.5) than Angus, Hereford, and Red Angus steaks (27.4, 27.7, and 26.3, respectively). Thus, a* changed less (P < 0.05) in Charolais and Limousin steaks (1.8 and 2.6, respectively) vs. steaks from other breeds. Day 6 b* values were greater (P < 0.05) in Charolais (24.5) and Limousin steaks (24.0) vs. Gelbvieh (22.2), Hereford (21.9), and Red Angus steaks (21.4). Thus, b* values changed less (P < 0.05) in Charolais and Limousin steaks (1.5 and 1.7, respectively) than in Angus, Gelbvieh, Hereford, and Red Angus steaks (4.3, 3.8, 4.4, and 5.1, respectively). After 6 d of display, Charolais and Limousin steaks had greater chroma (P < 0.05; 39.5 and 38.8, respectively) compared with Angus, Hereford, and Red Angus steaks (35.4, 35.3, and 33.9, respectively). Less (P < 0.05) change in chroma occurred for Charolais and Limousin (2.1 and 2.8, respectively) than in Angus, Gelbvieh, Hereford, and Red Angus steaks (7.1, 6.6, 7.4, and 9.0, respectively). Myoglobin concentration was less for Charolais and Limousin (P < 0.05; 2.77 and 2.72, respectively) compared with Gelbvieh, Red Angus, and Simmental steaks (3.62, 3.43, and 3.71, respectively). Breeds did not differ in pH (P > 0.05). These data suggest Charolais- and Limousin-carcasses produced steaks with greater lean color stability than Angus, Hereford, and Red Angus carcasses. Furthermore, these findings suggest that genetics contribute substantially to animal-to-animal variation in lean color, particularly in maintaining color.

Wipes, Coatings, and Patches for Detecting Hydrazines

NASA Technical Reports Server (NTRS)

Young, Rebecca; Buttner, William

2005-01-01

Three color-indicating devices have been conceived as simple, rapid, inexpensive means of detecting hazardous liquid and gaseous substances in settings in which safety is of paramount concern and it would be too time-consuming or otherwise impractical to perform detection by use of such instruments as mass spectrometers. More specifically, these devices are designed for detecting hypergolic fuels (in particular, hydrazines) and hypergolic oxidizers in spacecraft settings, where occasional leakage of these substances in liquid or vapor form occurs and it is imperative to take early corrective action to minimize adverse health effects. With suitable redesign, including reformulation of their color indicator chemicals, these devices could be adapted to detection of other hazardous substances in terrestrial settings (e.g., industrial and military ones). One of the devices is a pad of a commercially available absorbent material doped with a color indicator. The absorbent material is made from 70 percent polyester and 30 percent nylon and can absorb about eight times its own weight of liquid. The color indicator is a mixture of conventional pH color indicator chemicals. Hydrazine and monomethyl hydrazine, which are basic, cause the color indicator to turn green. In the original intended application, the pad is wiped on a space suit that is suspected of having been exposed to leaking monomethyl hydrazine during a space walk, before the wearer returns to the interior of the spacecraft. If the wiped surface is contaminated with hydrazine, the pad turns green. In addition, the pad absorbs hydrazine from the wiped surface, thereby reducing or eliminating the hazard. Used pads, including ones that show contamination by hydrazine, can be stored in a sealed plastic bag for subsequent disposal. The second device, which has been proposed but not yet developed, would comprise a color indicator material in the form of either a coating on a space suit (or other protective garment) or a coating on a sheet that could be easily attached to and detached from the protective garment. The coating material would be a hydrogel doped with a suitable pH indicator. The hydrogel would also serve to maintain a level of moisture needed to support the chemical reaction mentioned in the next sentence. In addition to changing color to indicate the presence of any hypergolic fuel (which is basic) or hypergolic oxidizer (which is acidic) that might splash on the space suit, the pH indicator would also react with the hypergolic fuel or oxidizer and thereby bind it. The third device is a color dosimeter for detecting hydrazine liquid or vapor coming from microscopic leaks. This device is designed to satisfy several requirements specific to its original intended use in the auxiliary power unit of the space shuttle. These requirements include stability under vacuum, stability at moderate temperature, fast and irreversible change in color upon exposure to hydrazine, and visibility of the color change through polyimide tape.

Color Stability Assessment of Two Different Composite Resins with Variable Immersion Time Using Various Beverages: An In vitro Study

PubMed Central

Kumar, M. Senthil; Ajay, R.; Miskeen Sahib, S. A.; Chittrarasu, M.; Navarasu, M.; Ragavendran, N.; Burhanuddin Mohammed, Omar Farooq

2017-01-01

Purpose of the Study: The aim of the study was to evaluate the difference in the color of microhybrid (MH) and nanofilled (NF) composite resins after 24 and 48 h in beverages such as red wine (RW), Coca-Cola, and distilled water. The specific objective of this study was to investigate the cumulative effect of the colorant solutions on the dental composites. Materials and Methods: MH and NF composite resins (A2 shade) were used in this current study. Sixty disk-shaped material specimens (10 mm in diameter × 2 mm in thickness) were prepared using a fiber mold (ring), with the desired dimensions. The specimen surfaces were polished using super-snap polishing system. Sixty specimens were divided into two groups of 30 each (Group I: MH resin composite; Group II: NF resin composite). Both the groups divided into six subgroups (Subgroup I: RW for 24 h [RW-24]; Subgroup II: RW for 48 h; Subgroup III: Coca-Cola for 24 h [CC-24]; Subgroup IV: Coca-Cola for 48 h [CC-48]; Subgroup V: Distilled water for 24 h [DW-24]; Subgroup VI: Distilled water for 48 h [DW-48]). All the samples were immersed in respective drinks for a period of 24 h, and color differences were measured using ultraviolet spectrophotometer. Once again, all the samples were immersed for another 24 h in the same drinks. After 48 h, the color change of the samples was measured. Measurements were made according to the CIE L × a × b × color space relative to the CIE standard illuminant D65. The color changes of the specimens were evaluated using the following formula: Statistical analysis was performed. The data were analyzed using the one-way ANOVA and t-test at a significance level of 0.05. Conclusion: Color stability of MH composite resin was found to be inferior than the NF resin composite irrespective of immersion medium and time. In RW, the color change observed was maximum for both composite resins followed by Coca-Cola. Immersing the resin composites in distilled water for 24 and 48 h had negligible color change. A 48-h immersion of both composite resins in all three immersion mediums showed greater color change than 24 h immersion. PMID:29284957

Color Stability Assessment of Two Different Composite Resins with Variable Immersion Time Using Various Beverages: An In vitro Study.

PubMed

Kumar, M Senthil; Ajay, R; Miskeen Sahib, S A; Chittrarasu, M; Navarasu, M; Ragavendran, N; Burhanuddin Mohammed, Omar Farooq

2017-11-01

The aim of the study was to evaluate the difference in the color of microhybrid (MH) and nanofilled (NF) composite resins after 24 and 48 h in beverages such as red wine (RW), Coca-Cola, and distilled water. The specific objective of this study was to investigate the cumulative effect of the colorant solutions on the dental composites. MH and NF composite resins (A2 shade) were used in this current study. Sixty disk-shaped material specimens (10 mm in diameter × 2 mm in thickness) were prepared using a fiber mold (ring), with the desired dimensions. The specimen surfaces were polished using super-snap polishing system. Sixty specimens were divided into two groups of 30 each (Group I: MH resin composite; Group II: NF resin composite). Both the groups divided into six subgroups (Subgroup I: RW for 24 h [RW-24]; Subgroup II: RW for 48 h; Subgroup III: Coca-Cola for 24 h [CC-24]; Subgroup IV: Coca-Cola for 48 h [CC-48]; Subgroup V: Distilled water for 24 h [DW-24]; Subgroup VI: Distilled water for 48 h [DW-48]). All the samples were immersed in respective drinks for a period of 24 h, and color differences were measured using ultraviolet spectrophotometer. Once again, all the samples were immersed for another 24 h in the same drinks. After 48 h, the color change of the samples was measured. Measurements were made according to the CIE L × a × b × color space relative to the CIE standard illuminant D65. The color changes of the specimens were evaluated using the following formula: Statistical analysis was performed. The data were analyzed using the one-way ANOVA and t -test at a significance level of 0.05. Color stability of MH composite resin was found to be inferior than the NF resin composite irrespective of immersion medium and time. In RW, the color change observed was maximum for both composite resins followed by Coca-Cola. Immersing the resin composites in distilled water for 24 and 48 h had negligible color change. A 48-h immersion of both composite resins in all three immersion mediums showed greater color change than 24 h immersion.

Natural Colorants: Food Colorants from Natural Sources.

PubMed

Sigurdson, Gregory T; Tang, Peipei; Giusti, M Mónica

2017-02-28

The color of food is often associated with the flavor, safety, and nutritional value of the product. Synthetic food colorants have been used because of their high stability and low cost. However, consumer perception and demand have driven the replacement of synthetic colorants with naturally derived alternatives. Natural pigment applications can be limited by lower stability, weaker tinctorial strength, interactions with food ingredients, and inability to match desired hues. Therefore, no single naturally derived colorant can serve as a universal alternative for a specified synthetic colorant in all applications. This review summarizes major environmental and biological sources for natural colorants as well as nature-identical counterparts. Chemical characteristics of prevalent pigments, including anthocyanins, carotenoids, betalains, and chlorophylls, are described. The possible applications and hues (warm, cool, and achromatic) of currently used natural pigments, such as anthocyanins as red and blue colorants, and possible future alternatives, such as purple violacein and red pyranoanthocyanins, are also discussed.

Noise enhanced stability of a metastable state containing coupled Brownian particles

NASA Astrophysics Data System (ADS)

Singh, R. K.

2017-05-01

Dynamics of coupled Brownian particles with color correlated additive Gaussian colored noises in a metastable state is analyzed to study the phenomenon of noise enhanced stability. The lifetime of such a metastable state is found to depend on the noise correlations and initial conditions. Dynamics of the slow variable is analyzed using the method of adiabatic elimination in the weak color limit.

Color attributes and oxidative stability of longissimus lumborum and psoas major muscles from Nellore bulls.

PubMed

Canto, Anna C V C S; Costa-Lima, Bruno R C; Suman, Surendranath P; Monteiro, Maria Lucia G; Viana, Fernanda M; Salim, Ana Paula A A; Nair, Mahesh N; Silva, Teofilo J P; Conte-Junior, Carlos A

2016-11-01

The influence of muscle source on color stability of fresh beef from purebred Bos indicus cattle was investigated. Longissimus lumborum (LL) and psoas major (PM) muscles obtained from twelve (n=12) Nellore bull carcasses (24h post-mortem) were fabricated into 2.54-cm steaks, aerobically packaged, and stored at 4°C for nine days. Steaks were analyzed on day 0 for proximate composition and myoglobin concentration, whereas pH, instrumental color, metmyoglobin reducing activity (MRA), lipid oxidation, and protein oxidation were evaluated on days 0, 3, 6, and 9. LL steaks exhibited greater (P<0.05) redness, color stability, and MRA than PM counterparts. On the other hand, PM steaks demonstrated greater (P<0.05) myoglobin content, lipid oxidation, and protein oxidation than LL steaks. These results indicated the critical influence of muscle source on discoloration of fresh beef from Bos indicus animals and suggested the necessity to engineer muscle-specific strategies to improve color stability and marketability of beef from Bos indicus cattle. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Interaction between Surface Color and Color Knowledge: Behavioral and Electrophysiological Evidence

ERIC Educational Resources Information Center

Bramao, Ines; Faisca, Luis; Forkstam, Christian; Inacio, Filomena; Araujo, Susana; Petersson, Karl Magnus; Reis, Alexandra

2012-01-01

In this study, we used event-related potentials (ERPs) to evaluate the contribution of surface color and color knowledge information in object identification. We constructed two color-object verification tasks--a surface and a knowledge verification task--using high color diagnostic objects; both typical and atypical color versions of the same…

Color constancy for an unseen surface.

PubMed

Norman, Liam J; Akins, Kathleen; Heywood, Charles A; Kentridge, Robert W

2014-12-01

The illumination of a scene strongly affects our perception of objects in that scene, e.g., the pages of a book illuminated by candlelight will appear quite yellow relative to other types of artificial illuminants. Yet at the same time, the reader still judges the pages as white, their surface color unaffected by the interplay of paper and illuminant. It has been shown empirically that we can indeed report two quite different interpretations of "color": one is dependent on the constant surface spectral reflectance of an object (surface color) and the other on the power of light of different wavelengths reflected from that object (reflected color). How then are these two representations related? The common view, dating from Aristotle, is that our experience of surface color is derived from reflected color or, in more familiar terms, that color perception follows from color sensation. By definition, color constancy requires that vision "discounts the illuminant"; thus, it seems reasonable that vision begins with the color of objects as they naively appear and that we infer from their appearances their surface color. Here, we question this classic view. We use metacontrast-masked priming and, by presenting the unseen prime and the visible mask under different illuminants, dissociate two ways in which the prime matched the mask: in surface color or in reflected color. We find that priming of the mask occurs when it matches the prime in surface color, not reflected color. It follows that color perception can arise without prior color sensation. Copyright © 2014 Elsevier Ltd. All rights reserved.

[Structure and properties of colored dental tetragonal zirconia stabilized by yttrium ceramics].

PubMed

Yi, Yuan-fu; Wang, Chen; Wen, Ning; Lin, Yong-zhao; Tian, Jie-mo

2009-10-01

To investigate the structure, mechanical and low temperature aging properties of colored dental zirconia ceramics. 5 graded colored dental zirconia ceramics were made by adding colorants and their combinations into a 3Y-TZP (tetragonal zirconia stabilized by 3mol% yttrium) powder, the green body were compacted at 200 MPa, pre-sinter at 1,050 degrees C and maintained for 2 h, then densely sintered at 1,500 degrees C for 2 h. Specimens were cut from each of the 5 graded colored blocks. Physical, mechanical properties as well as chemical stability were tested, microstructure were observed, crystalline phase were identified by X-ray diffraction (XRD), aging properties were assessed by measurement of the relative content of monoclinic phase and bending strength testing. The overall density of colored zirconia ceramics was over 99.7%, linear shrinkage was about 20%, while thermal expansion coefficient was about 11 x 10(-6) x degrees C(-1), the crystalline phase was tetragonal, bending strength was over 900 MPa which was slightly lowered than that of the uncolored zirconia, fracture toughness was slightly higher. Good chemical stability in acetic acid was observed. After aging treatment, tetragonal-to-monoclinic phase transformation was detected up to 40%, while bending strength was not significantly degraded. The results showed that colored 3Y-TZP ceramics presented good mechanical properties even after aging treatments, and was suitable for dental clinical use.

Alteration of blue pigment in artificial iris in ocular prosthesis: effect of paint, drying method and artificial aging.

PubMed

Goiato, Marcelo Coelho; Fernandes, Aline Úrsula Rocha; dos Santos, Daniela Micheline; Hadadd, Marcela Filié; Moreno, Amália; Pesqueira, Aldiéris Alves

2011-02-01

The artificial iris is the structure responsible for the dissimulation and aesthetics of ocular prosthesis. The objective of the present study was to evaluate the color stability of artificial iris of microwaveable polymerized ocular prosthesis, as a function of paint type, drying method and accelerated aging. A total of 40 discs of microwaveable polymerized acrylic resin were fabricated, and divided according to the blue paint type (n = 5): hydrosoluble acrylic, nitrocellulose automotive, hydrosoluble gouache and oil paints. Paints where dried either at natural or at infrared light bulb method. Each specimen was constituted of one disc in colorless acrylic resin and another colored with a basic sclera pigment. Painting was performed in one surface of one of the discs. The specimens were submitted to an artificial aging chamber under ultraviolet light, during 1008 h. A reflective spectrophotometer was used to evaluate color changes. Data were evaluated by 3-way repeated-measures ANOVA and the Tukey HSD test (α = 0.05). All paints suffered color alteration. The oil paint presented the highest color resistance to artificial aging regardless of drying method. Copyright © 2010 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

Nitrite spray treatment to promote red color stability of vacuum packaged beef.

PubMed

Song, Xiao; Cornforth, Daren; Whittier, Dick; Luo, Xin

2015-01-01

Sodium nitrite solutions were sprayed on select grade boneless rib (M. longissimus thoracis) and bottom round (mainly M. biceps femoris) steaks individually, to form bright red nitric oxide myoglobin (NO-Mb) in vacuum packages. Our objective was to determine the optimum level of nitrite in spray for stable raw steak redness, low or no residual nitrite, and low surface pinking (ham-like cured color) after cooking. Results showed that steaks sprayed with 100-350 ppm nitrite solutions had 3.0-3.6g weight gain and a calculated level of 1.3-5.3mg nitrite added/kg steak, but very low (<1 ppm) residual nitrite. Nitrite sprays of 250-350 ppm were optimum for raw steak color during 21 days of storage at 1°C (a*>10; chroma C*>16). Raw steak redness was less stable in round than rib. Visual scores for pinkness after cooking were low, indicating that cooked color at even the highest nitrite treatment (350 ppm) was acceptable. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nitrite-embedded packaging film effects on fresh and frozen beef color development and stability as influenced by meat age and muscle type.

PubMed

Claus, James R; Du, Chen

2013-11-01

Muscles (Longissimus lumborum, LL; Psoas major, PM, semitendinosus, ST) were aged (2, 9d postmortem), cut into steaks, anaerobically packaged (nitrite-embedded film, NEF), and displayed (fresh, 19d; frozen, 39d). Fresh NEF increased (P<0.05) in redness (first 48h). Upon opening fresh NEF (d 6) and overwrapping in PVC film, redness declined (P<0.05). NEF cooked LL had more red surface compared to non-NEF. Meat age influenced NEF color. Intact NEF maintained acceptable red color throughout display. Residual nitrite and nitrate associated with fresh NEF and nitrate in NEF cooked LL were found (P<0.05) in the outer layer. Consideration should be given to providing sufficient time for nitric oxide myoglobin development when using NEF which may be influenced by meat age and muscle differences. NEF packaging has potential to extend fresh beef color display life. NEF appears to offer the opportunity to display bright red beef in frozen display by limiting typical effects of photooxidation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Slope-aspect color shading for parametric surfaces

NASA Technical Reports Server (NTRS)

Moellering, Harold J. (Inventor); Kimerling, A. Jon (Inventor)

1991-01-01

The invention is a method for generating an image of a parametric surface, such as the compass direction toward which each surface element of terrain faces, commonly called the slope-aspect azimuth of the surface element. The method maximizes color contrast to permit easy discrimination of the magnitude, ranges, intervals or classes of a surface parameter while making it easy for the user to visualize the form of the surface, such as a landscape. The four pole colors of the opponent process color theory are utilized to represent intervals or classes at 90 degree angles. The color perceived as having maximum measured luminance is selected to portray the color having an azimuth of an assumed light source and the color showing minimum measured luminance portrays the diametrically opposite azimuth. The 90 degree intermediate azimuths are portrayed by unique colors of intermediate measured luminance, such as red and green. Colors between these four pole colors are used which are perceived as mixtures or combinations of their bounding colors and are arranged progressively between their bounding colors to have perceived proportional mixtures of the bounding colors which are proportional to the interval's angular distance from its bounding colors.

Development of the RGB LEDs color mixing mechanism for stability the color temperature at different projection distances.

PubMed

Hung, Chih-Ching

2015-01-01

In lighting application, the color mixing of the RGB LEDs can provide more color selection in correlated color temperature and color rendering. Therefore, the purpose of this study is to propose a RGB color mixing mechanism by applying the mechanism design. Three sets of lamp-type RGB LEDs are individually installed on three four-bar linkages. A crank is used to drive three groups of RGB LEDs lamp-type to project lights onto a single plane in order to mix the lights. And, simulations of the illuminance and associated color temperatures are conducted by changing the distance to the projection plane, under the assumption that the stability of the color temperature of the projected light does not change according to the projecting height. Thus, the effect of change in the color temperature on color determination by the humans' eyes was avoided. The success of the proposed method will allow medical personnel to choose suitable wavelengths and color temperatures according to the particular requirements of their medical-examination environments.

Spectrophotometric determination of L-cysteine by using polyvinylpyrrolidone-stabilized silver nanoparticles in the presence of barium ions.

PubMed

Bamdad, Farzad; Khorram, Fateme; Samet, Maryam; Bamdad, Kourosh; Sangi, Mohammad Reza; Allahbakhshi, Fateme

2016-05-15

In this article a simple and selective colorimetric probe for cysteine determination using silver nano particles (AgNPS) is described. The determination process was based upon the surface plasmon resonance properties of polyvinylpyrrolidone-stabilized AgNPS. Interaction of AgNPS with cysteine molecules in the presence of barium ions induced a red shift in the surface plasmon resonance (SPR) maximum of AgNPs, as a result of nanoparticle aggregation. Consequently, yellow color of AgNP solution was changed to pink. The linear range for the determination of cysteine was 3.2-8.2 μM (R=0.9965) with a limit of detection equal to 2.8 μM (3σ). The proposed method was successfully applied to the determination of cysteine in human plasma samples. Acceptable recovery results of the spiked samples confirmed the validity of the proposed method. Copyright © 2016 Elsevier B.V. All rights reserved.

Spectrophotometric determination of L-cysteine by using polyvinylpyrrolidone-stabilized silver nanoparticles in the presence of barium ions

NASA Astrophysics Data System (ADS)

Bamdad, Farzad; Khorram, Fateme; Samet, Maryam; Bamdad, Kourosh; Sangi, Mohammad Reza; Allahbakhshi, Fateme

2016-05-01

In this article a simple and selective colorimetric probe for cysteine determination using silver nano particles (AgNPS) is described. The determination process was based upon the surface plasmon resonance properties of polyvinylpyrrolidone-stabilized AgNPS. Interaction of AgNPS with cysteine molecules in the presence of barium ions induced a red shift in the surface plasmon resonance (SPR) maximum of AgNPs, as a result of nanoparticle aggregation. Consequently, yellow color of AgNP solution was changed to pink. The linear range for the determination of cysteine was 3.2-8.2 μM (R = 0.9965) with a limit of detection equal to 2.8 μM (3σ). The proposed method was successfully applied to the determination of cysteine in human plasma samples. Acceptable recovery results of the spiked samples confirmed the validity of the proposed method.

Illusory color mixing upon perceptual fading and filling-in does not result in 'forbidden colors'.

PubMed

Hsieh, P-J; Tse, P U

2006-07-01

A retinally stabilized object readily undergoes perceptual fading. It is commonly believed that the color of the apparently vanished object is filled in with the color of the background because the features of the filled-in area are determined by features located outside the stabilized boundary. Crane, H. D., & Piantanida, T. P. (1983) (On seeing reddish green and yellowish blue. Science, 221, 1078-1080) reported that the colors that are perceived upon full or partial perceptual fading can be 'forbidden' in the sense that they violate color opponency theory. For example, they claimed that their subjects could perceive "reddish greens" and "yellowish blues." Here we use visual stimuli composed of spatially alternating stripes of two different colors to investigate the characteristics of color mixing during perceptual filling-in, and to determine whether 'forbidden colors' really occur. Our results show that (1) the filled-in color is not solely determined by the background color, but can be the mixture of the background and the foreground color; (2) apparent color mixing can occur even when the two colors are presented to different eyes, implying that color mixing during filling-in is in part a cortical phenomenon; and (3) perceived colors are not 'forbidden colors' at all, but rather intermediate colors.

In vitro evaluation of color change in maxillofacial elastomer through the use of an ultraviolet light absorber and a hindered amine light stabilizer.

PubMed

Tran, Ngoc H; Scarbecz, Mark; Gary, John J

2004-05-01

External prostheses composed of silicone elastomers exhibit an unwanted color change over time. This study evaluated color stability when an ultraviolet light absorber and hindered amine light stabilizer were mixed in the maxillofacial elastomer containing either organic or inorganic pigments. The materials used were an RTV silicone elastomer, 1 natural inorganic dry-earth pigment (burnt sienna) and 2 synthesized organic pigments (hansa yellow and alizarin red), ultraviolet light absorber (UVA) and hindered amine light stabilizer (HALS). Specimens (n=160) were fabricated in a custom mold and randomly assigned and exposed to weathering sites in Miami and Phoenix for approximately 3 months. Eight test groups (2 of each 4 material types with or without additives) of 10 specimens each were assigned to each site. L*, a*, b* readings were obtained before and after weathering from a spectrocolorimeter. Nonpigmented elastomers served as the control. Three-factor ANOVA was conducted to examine interaction effects between weathering sites, specimen type, and the presence of additive (alpha=.05). Overall color change (Delta E) and change in color coordinates (Delta L*, Delta a*, Delta b*) of specimen groups with and without additive were analyzed with independent sample t tests. In specimen groups with the additives (UVA and HALS), color change decreased significantly (P<.05) in burnt sienna and hansa yellow in Phoenix and in the control and hansa yellow in Miami. Additives did not affect color change in the alizarin red group. UVA and HALS were shown to be effective in retarding color change in some circumstances.

Color stability of resin used for caries infiltration after exposure to different staining solutions.

PubMed

Borges, Ab; Caneppele, Tmf; Luz, M; Pucci, Cr; Torres, Crg

2014-01-01

PURPOSE : The aim of this study was to investigate the staining behavior of demineralized enamel infiltrated by low-viscosity resin. METHODS AND MATERIALS : Bovine enamel/dentin cylindrical samples (3 × 2 mm) were assigned into four groups (n=45) according to the enamel treatment: sound enamel (control), demineralization + artificial saliva, demineralization + daily application of 0.05% NaF, demineralization + resin infiltration (Icon, DMG). Artificial white spot lesions were produced in groups with demineralization. After the treatments, color was assessed by spectrophotometry, using the CIE L*a*b* system. The specimens (n=15) were then immersed in deionized water, red wine, or coffee for 10 minutes daily for eight days. Color was measured again, and the specimens were repolished with sandpaper discs. The final color was assessed. Data were analyzed by two-way analysis of variance and Tukey tests (α=0.05). A paired t-test was used for comparison between staining and repolishing conditions. RESULTS : There were significant differences for surface treatment and dye after staining and repolishing. Immersion in wine and coffee resulted in significantly increased color alteration (ΔE) compared with water (p=0.001). The resin-infiltrated group exhibited the highest staining values (p=0.001). The repolishing procedures resulted in significantly decreased color change. The exposure of specimens to colored solutions resulted in significant color alteration. The demineralized enamel treated with resin infiltration showed significantly higher staining than all other tested groups; however, the repolishing of the specimens minimized the staining effect.

The combined effect of food-simulating solutions, brushing and staining on color stability of composite resins

PubMed Central

Silva, Tânia Mara Da; Sales, Ana Luísa Leme Simões; Pucci, Cesar Rogerio; Borges, Alessandra Bühler; Torres, Carlos Rocha Gomes

2017-01-01

Abstract Objective: This study evaluated the effect of food-simulating media associated with brushing and coffee staining on color stability of different composite resins. Materials and methods: Eighty specimens were prepared for each composite: Grandio SO (Voco), Amaris (Voco), Filtek Z350XT (3M/ESPE), Filtek P90 (3M/ESPE). They were divided into four groups according to food-simulating media for 7 days: artificial saliva (control), heptane, citric acid and ethanol. The composite surface was submitted to 10,950 brushing cycles (200 g load) in an automatic toothbrushing machine. The specimens were darkened with coffee solution at 37 °C for 24 h. After each treatment, color measurements were assessed by spectrophotometry, using CIE L*a*b* system. The overall color change (ΔE) was determined for each specimen at baseline (C1) and after the treatments (food-simulating media immersion/C2, brushing/C3 and dye solution/C4). Data were analyzed by two-way repeated measures ANOVA and Tukey’s tests (p < .05). Results: The results of RM-ANOVA showed significant differences for composites (p = .001), time (p = .001) and chemical degradation (p = .002). The mean of ΔE for composites were: Z350XT (5.39)a, Amaris (3.89)b, Grandio (3.75)bc, P90 (3.36)c. According to food-simulating media: heptane (4.41)a, citric acid (4.24)a, ethanol (4.02)ab, artificial saliva (3.76)b. For the treatments: dye solution (4.53)a, brushing (4.26)a, after food-simulating media (3.52)b. Conclusions: The composite resin Filtek Z350XT showed significantly higher staining than all other composite resin tested. The immersion in heptane and citric acid produced the highest color alteration than other food-simulating media. The exposure of samples to brushing protocols and darkening in coffee solution resulted in significant color alteration of the composite resins. PMID:28642926

Heat stability of strawberry anthocyanins in model solutions containing natural copigments extracted from rose (Rosa damascena Mill.) petals.

PubMed

Shikov, Vasil; Kammerer, Dietmar R; Mihalev, Kiril; Mollov, Plamen; Carle, Reinhold

2008-09-24

Thermal degradation and color changes of purified strawberry anthocyanins in model solutions were studied upon heating at 85 degrees C by HPLC-DAD analyses and CIELCh measurements, respectively. The anthocyanin half-life values increased significantly due to the addition of rose (Rosa damascena Mill.) petal extracts enriched in natural copigments. Correspondingly, the color stability increased as the total color difference values were smaller for anthocyanins upon copigment addition, especially after extended heating. Furthermore, the stabilizing effect of rose petal polyphenols was compared with that of well-known copigments such as isolated kaempferol, quercetin, and sinapic acid. The purified rose petal extract was found to be a most effective anthocyanin-stabilizing agent at a molar pigment/copigment ratio of 1:2. The results obtained demonstrate that the addition of rose petal polyphenols slows the thermal degradation of strawberry anthocyanins, thus resulting in improved color retention without affecting the gustatory quality of the product.

Effect of slaughter age on the antioxidant enzyme activity, color, and oxidative stability of Korean Hanwoo (Bos taurus coreanae) cow beef.

PubMed

Cho, Soohyun; Kang, Geunho; Seong, Pil-Nam; Park, Beomyoung; Kang, Sun Moon

2015-10-01

This study investigated the effect of slaughter age on the antioxidant enzyme activity, lipid and protein oxidation, and color stability in striploins (M. longissimus lumborum) from Korean Hanwoo (Bos taurus coreanae) cows of different age groups (1.9 to 3.7, 4.0 to 4.8, 5.0 to 5.7, 6.0 to 6.9, and 7.5 to 11.5yr). Myoglobin content and the activities of catalase, superoxide dismutase, and glutathione peroxidase were significantly (P<0.05) increased in older cow beef. During refrigerated storage, 2-thiobarbituric acid reactive substances and protein carbonyls were significantly (P<0.05) increased in the meat from the older cows. The beef from older cows was darker and had lower color stability. These findings suggest that slaughter age has a negative effect on the color and lipid stability of Hanwoo cow beef. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of extended aging and modified atmospheric packaging on beef top loin steak color.

PubMed

English, A R; Mafi, G G; VanOverbeke, D L; Ramanathan, R

2016-04-01

The objective of this study was to evaluate the effects of extended aging and modified atmospheric packaging on beef LM color. Using a randomized complete block design, each beef longissimus lumborum muscle ( = 10; USDA Choice, 3 d postmortem) was equally divided into 3 sections and randomly assigned to 1 of 3 aging periods (21, 42, or 62 d at 2°C). After respective aging, each loin section was cut into four 2.5-cm-thick steaks and randomly assigned to 1 of 3 packaging types (PVC, HiOx-MAP [80% oxygen and 20% carbon dioxide], or CO-MAP [0.4% carbon monoxide, 69.6% nitrogen, and 30% carbon dioxide]). The steaks were displayed under continuous fluorescent lighting for 6 d, and surface color was determined daily using a HunterLab Miniscan XE Plus spectrophotometer and a visual panel. The fourth steak was used to characterize oxygen consumption (OC), lipid oxidation, and metmyoglobin reducing activity (MRA) on 21, 42, and 62 d (before display). On d 6 display, MRA, OC, and lipid oxidation also were measured. An increase in aging time decreased ( < 0.0001) muscle pH. Loin sections aged for 42 and 62 d had a lower ( < 0.0002) pH compared with loin sections aged for 21 d. An aging period × packaging × display time interaction ( < 0.0001) resulted for a* values (redness), chroma, and visual color (muscle color and surface discoloration). As aging time increased, HiOx-MAP had the most discoloration ( < 0.0001) compared with other packaging types on d 6. At all aging periods, steaks packaged in CO-MAP had greater ( < 0.0001) MRA on d 6 than PVC and HiOx-MAP, whereas steaks packaged in HiOx-MAP had the least MRA ( < 0.0001). There were no differences ( = 0.34) in thiobarbituric acid reactive substances values between steaks aged for 21 and 42 d when steaks were packaged in CO-MAP and displayed for 6 d. However, steaks packaged in HiOx-MAP and displayed 6 d had greater ( < 0.0001) lipid oxidation than CO-MAP. Steaks packaged in HiOx-MAP had a lower ( < 0.0001) OC compared with PVC and CO-MAP when aged for 42 and 62 d. There were no differences ( = 0.49) in OC between steaks packaged in PVC and HiOx-MAP when aged for 21 d and displayed 6 d. The results indicate that extended aging is detrimental to color stability when packaged in PVC and HiOx-MAP. However, steaks in CO-MAP had stable red color during display. Decreased color stability in PVC and HiOx-MAP could be associated, in part, with decreased MRA and OC.

Evaluation of the color stability of two techniques for reproducing artificial irides after microwave polymerization

PubMed Central

GOIATO, Marcelo Coelho; dos SANTOS, Daniela Micheline; MORENO, Amália; GENNARI-FILHO, Humberto; PELLIZZER, Eduardo Piza

2011-01-01

The use of ocular prostheses for ophthalmic patients aims to rebuild facial aesthetics and provide an artificial substitute to the visual organ. Natural intemperate conditions promote discoloration of artificial irides and many studies have attempted to produce irides with greater chromatic paint durability using different paint materials. Objectives The present study evaluated the color stability of artificial irides obtained with two techniques (oil painting and digital image) and submitted to microwave polymerization. Material and Methods Forty samples were fabricated simulating ocular prostheses. Each sample was constituted by one disc of acrylic resin N1 and one disc of colorless acrylic resin with the iris interposed between the discs. The irides in brown and blue color were obtained by oil painting or digital image. The color stability was determined by a reflection spectrophotometer and measurements were taken before and after microwave polymerization. Statistical analysis of the techniques for reproducing artificial irides was performed by applying the normal data distribution test followed by 2-way ANOVA and Tukey HSD test (α=.05). Results Chromatic alterations occurred in all specimens and statistically significant differences were observed between the oil-painted samples and those obtained by digital imaging. There was no statistical difference between the brown and blue colors. Independently of technique, all samples suffered color alterations after microwave polymerization. Conclusion The digital imaging technique for reproducing irides presented better color stability after microwave polymerization. PMID:21625733

Number of perceptually distinct surface colors in natural scenes.

PubMed

Marín-Franch, Iván; Foster, David H

2010-09-30

The ability to perceptually identify distinct surfaces in natural scenes by virtue of their color depends not only on the relative frequency of surface colors but also on the probabilistic nature of observer judgments. Previous methods of estimating the number of discriminable surface colors, whether based on theoretical color gamuts or recorded from real scenes, have taken a deterministic approach. Thus, a three-dimensional representation of the gamut of colors is divided into elementary cells or points which are spaced at one discrimination-threshold unit intervals and which are then counted. In this study, information-theoretic methods were used to take into account both differing surface-color frequencies and observer response uncertainty. Spectral radiances were calculated from 50 hyperspectral images of natural scenes and were represented in a perceptually almost uniform color space. The average number of perceptually distinct surface colors was estimated as 7.3 × 10(3), much smaller than that based on counting methods. This number is also much smaller than the number of distinct points in a scene that are, in principle, available for reliable identification under illuminant changes, suggesting that color constancy, or the lack of it, does not generally determine the limit on the use of color for surface identification.

Modulation of the photoluminescence in carbon dots through surface modification: from mechanism to white light-emitting diodes.

PubMed

Zhu, Jinyang; Shao, He; Bai, Xue; Zhai, Yue; Zhu, Yongsheng; Chen, Xu; Pan, Gencai; Dong, Biao; Xu, Lin; Zhang, Hanzhuang; Song, Hongwei

2018-06-15

Carbon dots (CDs) have emerged as a new type of fluorescent material because of their unique optical advantages, such as high photoluminescence quantum yields (QYs), excellent photo-stability, excitation-dependent emissions, and low toxicity. However, the photoluminescence mechanism for CDs remains unclear, which limits their further practical application. Here, CDs were synthesized via a solvothermal route from citric acid and urea. Through the oxidation and reduction treatment of pristine CDs, the origin of the photoluminescence and the involved mechanism were revealed. We found that the blue/green/red emissions originated from three diverse emitting states, i.e. the intrinsic state, and C=O- and C=N-related surface states, respectively. Based on the as-prepared CDs, a pH sensor depending on the radiometric luminescence detection was developed. Furthermore, we constructed CD/PVP (PVP, polyvinylpyrrolidone) composite films, which exhibited white light emission with photoluminescence QYs of 15.3%. The white light emission with different correlated color temperatures (CCTs), from 4807 K to 3319 K, was obtained by simply changing the amount of PVP solution. Benefiting from the white light-emitting solid-state films, single-component white light-emitting diodes were fabricated with an average color rendering index value (Ra) of 80.0, luminous efficiency of 10.2 lm W -1 , and good working stability, thus indicating a promising potential for practical lighting applications.

Modulation of the photoluminescence in carbon dots through surface modification: from mechanism to white light-emitting diodes

NASA Astrophysics Data System (ADS)

Zhu, Jinyang; Shao, He; Bai, Xue; Zhai, Yue; Zhu, Yongsheng; Chen, Xu; Pan, Gencai; Dong, Biao; Xu, Lin; Zhang, Hanzhuang; Song, Hongwei

2018-06-01

Carbon dots (CDs) have emerged as a new type of fluorescent material because of their unique optical advantages, such as high photoluminescence quantum yields (QYs), excellent photo-stability, excitation-dependent emissions, and low toxicity. However, the photoluminescence mechanism for CDs remains unclear, which limits their further practical application. Here, CDs were synthesized via a solvothermal route from citric acid and urea. Through the oxidation and reduction treatment of pristine CDs, the origin of the photoluminescence and the involved mechanism were revealed. We found that the blue/green/red emissions originated from three diverse emitting states, i.e. the intrinsic state, and C=O- and C=N-related surface states, respectively. Based on the as-prepared CDs, a pH sensor depending on the radiometric luminescence detection was developed. Furthermore, we constructed CD/PVP (PVP, polyvinylpyrrolidone) composite films, which exhibited white light emission with photoluminescence QYs of 15.3%. The white light emission with different correlated color temperatures (CCTs), from 4807 K to 3319 K, was obtained by simply changing the amount of PVP solution. Benefiting from the white light-emitting solid-state films, single-component white light-emitting diodes were fabricated with an average color rendering index value (Ra) of 80.0, luminous efficiency of 10.2 lm W‑1, and good working stability, thus indicating a promising potential for practical lighting applications.

Proteomic analysis to investigate color changes of chilled beef longissimus steaks held under carbon monoxide and high oxygen packaging.

PubMed

Yang, Xiaoyin; Wu, Shuang; Hopkins, David L; Liang, Rongrong; Zhu, Lixian; Zhang, Yimin; Luo, Xin

2018-08-01

This study investigated the proteome basis for color stability variations in beef steaks packaged under two modified atmosphere packaging (MAP) methods: HiOx-MAP (80% O 2 /20% CO 2 ) and CO-MAP (0.4% CO/30% CO 2 /69.6% N 2 ) during 15 days of storage. The color stability, pH, and sarcoplasmic proteome analysis of steaks were evaluated on days 0, 5, 10 and 15 of storage. Proteomic results revealed that the differential expression of the sarcoplasmic proteome during storage contributed to the variations in meat color stability between the two MAP methods. Compared with HiOx-MAP steaks, some glycolytic and energy metabolic enzymes important in NADH regeneration and antioxidant processes, antioxidant peroxiredoxins (thioredoxin-dependent peroxide reductase, peroxiredoxin-2, peroxiredoxin-6) and protein DJ-1 were more abundant in CO-MAP steaks. The over-expression of these proteins could induce CO-MAP steaks to maintain high levels of metmyoglobin reducing activity and oxygen consumption rate, resulting in CO-MAP steaks exhibiting better color stability than HiOx-MAP steaks during storage. Copyright © 2018 Elsevier Ltd. All rights reserved.

Optimization of palm oil physical refining process for reduction of 3-monochloropropane-1,2-diol (3-MCPD) ester formation.

PubMed

Zulkurnain, Musfirah; Lai, Oi Ming; Tan, Soo Choon; Abdul Latip, Razam; Tan, Chin Ping

2013-04-03

The reduction of 3-monochloropropane-1,2-diol (3-MCPD) ester formation in refined palm oil was achieved by incorporation of additional processing steps in the physical refining process to remove chloroester precursors prior to the deodorization step. The modified refining process was optimized for the least 3-MCPD ester formation and acceptable refined palm oil quality using response surface methodology (RSM) with five processing parameters: water dosage, phosphoric acid dosage, degumming temperature, activated clay dosage, and deodorization temperature. The removal of chloroester precursors was largely accomplished by increasing the water dosage, while the reduction of 3-MCPD esters was a compromise in oxidative stability and color of the refined palm oil because some factors such as acid dosage, degumming temperature, and deodorization temperature showed contradictory effects. The optimization resulted in 87.2% reduction of 3-MCPD esters from 2.9 mg/kg in the conventional refining process to 0.4 mg/kg, with color and oil stability index values of 2.4 R and 14.3 h, respectively.

Color Stability of Composites After Short-term Oral Simulation: An in vitro Study

PubMed Central

Özdaş, Didem Öner; Kazak, Mağrur; Çilingir, Aylin; Subaşı, Meryem Gülce; Tiryaki, Murat; Günal, Şölen

2016-01-01

Background: Although most of the studies investigated color stability of different restorative materials, evaluation of color stability of composites after immersion in multiple beverages in the same day by an in vitro oral simulation study is unclear. Objective: To assess color change of different restorative materials at the end of days 1, 14, and 30 of immersion in multiple liquid types to mimic the oral environment in vitro. Method: Ten disc-shaped specimens were made from each of four different resin composites (Filtek Z250, Voco x-tra base, Beautifil Flow Plus, Beautifil II). Baseline color value of each sample was measured using a spectrophotometer. Each composite was respectively immersed in coffee, an orange/pomegranate juice mixture, black tea, and a mouth rinse on the same day to mimic daily liquid consumption of individuals. Color measurements were taken after 1, 14, and 30 days by spectrophotometer and color change values were calculated. Statistical analyses were executed by one-way ANOVA/Tukey HSD and repeated-measures ANOVA. Results: All materials showed significant color change after 1, 14, and 30 days (P < 0.01) of immersion in liquids, with the lowest color alteration observed at the 1st day and the highest observed after the 30th day. Among the materials tested, at each time point (1, 14, and 30 days), the lowest color alteration was detected in Filtek Z250 and the highest color alteration was detected in Beautifil II. Conclusion: Color alteration of composite resins is affected by composite type and storage time. With the exception of 1 day of storage, color changes of all materials were substantial and clinically unacceptable. PMID:27733871

Black bean anthocyanin-rich extracts as food colorants: Physicochemical stability and antidiabetes potential

USDA-ARS?s Scientific Manuscript database

Black beans contain anthocyanins that could be used as colorants in foods with associated health benefits. The objective was to optimize anthocyanins extraction from black bean coats and evaluate their physicochemical stability and antidiabetes potential. Optimal extraction conditions were 24% ethan...

Discoloration of different esthetic restorative materials: A spectrophotometric evaluation

PubMed Central

Ceci, Matteo; Viola, Matteo; Rattalino, Davide; Beltrami, Riccardo; Colombo, Marco; Poggio, Claudio

2017-01-01

Objective: A crucial property of esthetic restorative materials is their long-term color stability. The aim of this in vitro study was to evaluate the color stability of esthetic restorative materials (one microfilled flowable composite, one nanofilled composite, one nanoybrid composite, one microfilled composite, and one nanoybrid ormocer-based composite) after surface roughening with cola and exposure to different staining solutions (coffee and red wine). Materials and Methods: All materials were polymerized into silicone rubber rings (2 mm × 6 mm × 8 mm) to obtain 150 specimens identical in size. Seventy-five specimens of Group A were first exposed to cola for 24 h, and then samples were immersed in coffee or red wine over a 28-day test period. A colorimetric evaluation, according to the CIE L*a*b* system, was performed at 7, 14, 21, 28 days. Shapiro–Wilk test and Kruskal–Wallis analysis of variance were applied to assess significant differences among restorative materials. Means were compared with Scheffe's multiple comparison test at the 0.05 level of significance. Results: Specimens of Group A showed higher variations when compared with Group B's specimens (P < 0.05). After 28 days, the immersion protocols caused a clinically perceivable color change for all materials tested (P < 0.05). CeramX Universal and Admira Fusion showed the lowest ΔE variations (P < 0.05). Conclusions: Staining beverages caused significant discolorations for all the materials tested. The first exposure to cola enhanced the subsequent staining with coffee or red wine. Nanohybrid composites reported the lowest color variations. PMID:28729784

Effects of electrolytes and surfactants on the morphology and stability of advanced silver nano-materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Obaid, Abdullah Yousif; AL-Thabaiti, Shaeel Ahmed; El-Mossalamy, E.H.

2013-03-15

Highlights: ► Stoichiometric ratio of S{sub 2}O{sub 3}{sup 2−} and Ag{sup +} ions are responsible to the formation of prefect transparent yellow colored silver sol. ► Higher S{sub 2}O{sub 3}{sup 2−} concentrations has damping effect. ► Head group of the surfactants and nature of the electrolytes have significant effect on the stability of silver nanoparticles. - Abstract: The impact of electrolytes, stabilizing and/or capping agents on morphology of colloidal silver nano-materials (AgNPs) has been studied spectroscopically. Sodium thiosulfate acts as reducing-, stabilizing- and damping-agents. Stoichiometric ratios of S{sub 2}O{sub 3}{sup 2−} and Ag{sup +} ions were responsible to the formationmore » stable and prefect transparent dark yellow colored AgNPs. The S{sub 2}O{sub 3}{sup 2−}-stabilized AgNPs were significantly more stable in inorganic electrolytes (NaNO{sub 3}, Na{sub 2}SO{sub 4}, Na{sub 2}CO{sub 3} and KBr). S{sub 2}O{sub 3}{sup 2−} is adsorbed more strongly than the used other anions. The addition of cetyltrimethylammonium bromide (CTAB) and sodium dodecylsulfate (SDS) has significant effects on the absorbance of S{sub 2}O{sub 3}{sup 2−}-stabilized AgNPs which can be rationalized in terms of electrostatic attraction and repulsion between the adsorbed S{sub 2}O{sub 3}{sup 2−} ions on to the surface of AgNPs and cationic and/or anionic head groups of used surfactants, respectively. Transmission electron microscopy images suggest that AgNPs are polydispersed, spherical and exhibiting an interesting irregular morphology.« less

Color in the corners: ITO-free white OLEDs with angular color stability.

PubMed

Gaynor, Whitney; Hofmann, Simone; Christoforo, M Greyson; Sachse, Christoph; Mehra, Saahil; Salleo, Alberto; McGehee, Michael D; Gather, Malte C; Lüssem, Björn; Müller-Meskamp, Lars; Peumans, Peter; Leo, Karl

2013-08-07

High-efficiency white OLEDs fabricated on silver nanowire-based composite transparent electrodes show almost perfectly Lambertian emission and superior angular color stability, imparted by electrode light scattering. The OLED efficiencies are comparable to those fabricated using indium tin oxide. The transparent electrodes are fully solution-processable, thin-film compatible, and have a figure of merit suitable for large-area devices. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

QCD pairing in primordial nuggets

NASA Astrophysics Data System (ADS)

Lugones, G.; Horvath, J. E.

2003-08-01

We analyze the problem of boiling and surface evaporation of quark nuggets in the cosmological quark-hadron transition. Recently, it has been shown that QCD pairing modifies the stability properties of strange quark matter. More specifically, strange quark matter in a color-flavor locked state was found to be absolutely stable for a much wider range of the parameters than ordinary unpaired strange quark matter (G. Lugones and J. E. Horvath, Phys. Rev. D, 66, 074017 (2002)). Assuming that primordial quark nuggets are actually formed we analyze the consequences of pairing on the rates of boiling and surface evaporation in order to determine whether they could have survived.

Prediction of Pork Longissimus Lean Color Stability Using VIS/NIR

USDA-ARS?s Scientific Manuscript database

Insufficient case-life is a costly problem facing pork processors. To assess Visible and Near-Infrared (VIS/NIR) spectroscopy as a technology to sort pork loins according to lean color stability, center-cut pork loins (n = 1208) were selected from the boning lines of four large-scale pork processor...

Influence of mitochondrial efficiency on beef lean color stability

USDA-ARS?s Scientific Manuscript database

Loss of electrons in the electron transport chain has been implicated as a source of variation in feed efficiency of meat producing animals. The present study was conducted to evaluate the effects of electron loss during electron transport on beef lean color stability. Beef carcasses (n = 91) were...

Color Stability Behavior of Methacrylate-based Resin Composites Polymerized with Light-emitting Diodes and Quartz-Tungsten-Halogen.

PubMed

Sabatini, C

2015-01-01

Despite significant developments in improving the optical properties of resin composite materials, their color stability remains a challenge. This study aimed to evaluate the shade stability of light-polymerized, methacrylate-based resin composites with different filler particle composition (microfill, minifill, nanohybrids, and microhybrids) polymerized with quartz-tungsten-halogen (QTH) and light-emitting diodes (LED). Composite discs were fabricated from Tetric EvoCeram, Premise, Artiste, and Beautifil II (nanohybrids); Filtek Supreme Plus and Vit-l-escence (microhybrids); Heliomolar (microfill); and Estelite Sigma Quick (minifill) using a Teflon mold. The specimens were irradiated either with QTH (Elipar 2500; 600 mW/cm(2)) for 40 seconds or with LED (Bluephase G2; 1200 mW/cm(2)) for 20 seconds. Color parameters were measured with a colorimeter before and after polymerization and at 24 hours, one week, one month, and three months. Color change was calculated among the different storage periods. There was a significant effect of the composite, time, and their interaction (p<0.001) but no effect of the polymerization unit on the color stability. Color changes immediately after polymerization and at 24 hours (4.22 and 3.88 for LED; and 4.08 and 3.82 for QTH) were not significantly different from each other but were both significantly higher than changes after one week (0.96 and 0.78), one month (1.12 and 1.02), and three months (1.27 and 1.11) for LED and QTH, respectively (p<0.001). Color changes were observed for all the materials that were dependent on the type of composite but not on the polymerization unit. These color shifts took place primarily immediately after polymerization and after 24 hours and were additive in nature.

Color stability and marginal integrity of interim crowns: An in vitro study

PubMed Central

Elagra, Marwa I.; Rayyan, Mohammad R.; Alhomaidhi, Maisam M.; Alanaziy, Areej A.; Alnefaie, Mona O.

2017-01-01

Objective: Many commercial dental materials are used to fabricate interim restorations. This study aimed to compare the color stability and the marginal integrity of four different interim crown materials. Materials and Methods: An ivorine right maxillary central incisor was prepared for a full coverage all-ceramic restoration. A total of 36 specimens in the form of crowns were fabricated on the master die using four different materials (n = 9); Polymethyl methacrylate (PMMA) resin (TrimPLUS), PMMA computer-aided design, and computer-aided manufacturing (CAD-CAM) blocks (Ceramill TEMP), cold cure bis-acryl resin (Success CD), and bis-acryl resin dual-cure composite (TempSpan). Color change ΔE for each sample was calculated by measuring its color as Commission Internationale de l’Eclairage L* a* b* with a spectrophotometer before and after immersing in a concentrated tea solution for 7 days. Marginal gap was measured at four reference points using stereomicroscope at ×40. One-way ANOVA and the Tukey multiple comparisons test were used to determine any statistically significant difference between the four groups, (α = 0.05). Results: Success CD showed significantly the greatest color change (7.7) among all the tested materials, while no significant difference was found between the other three materials. TempSpan showed significantly the highest marginal gap formation (430.15 μm), while no significant difference was found between the three other materials. Conclusions: Bis-acryl resin composite materials demonstrated clinically noticeable change in color while PMMA materials demonstrated superior color stability. Dual cure interim materials exhibited significantly higher marginal discrepancy in comparison to PMMA and cold cure bis-acrylic resin materials. CAD-CAM PMMA material exhibited the best color stability and marginal integrity. PMID:28932142

Effect of Various Packaging Methods on Small-Scale Hanwoo (Korean Native Cattle) during Refrigerated Storage

PubMed Central

Yu, Hwan Hee; Song, Myung Wook; Kim, Tae-Kyung; Choi, Yun-Sang; Cho, Gyu Yong; Lee, Na-Kyoung; Paik, Hyun-Dong

2018-01-01

Abstract The objective of this study was to investigate comparison of physicochemical, microbiological, and sensory characteristics of Hanwoo eye of round by various packaging methods [wrapped packaging (WP), modified atmosphere packaging (MAP), vacuum packaging (VP) with three different vacuum films, and vacuum skin packaging (VSP)] at a small scale. Packaged Hanwoo beef samples were stored in refrigerated conditions (4±1°C) for 28 days. Packaged beef was sampled on days 0, 7, 14, 21, and 28. Physicochemical [pH, surface color, thiobarbituric acid reactive substances (TBARS), and volatile basic nitrogen (VBN) values], microbiological, and sensory analysis of packaged beef samples were performed. VP and VSP samples showed low TBARS and VBN values, and pH and surface color did not change substantially during the 28-day period. For VSP, total viable bacteria, psychrotrophic bacteria, lactic acid bacteria, and coliform counts were lower than those for other packaging systems. Salmonella spp. and Escherichia coli O157:H7 were not detected in any packaged beef samples. A sensory analysis showed that the scores for appearance, flavor, color, and overall acceptability did not change significantly until day 7. In total, VSP was effective with respect to significantly higher a* values, physicochemical stability, and microbial safety in Hanwoo packaging (p<0.05). PMID:29805283

Colorimetric detection of trivalent chromium in aqueous solution using tartrate-capped silver nanoparticles as probe.

PubMed

Xu, Yunbo; Dong, Yangjun; Jiang, Xue; Zhu, Ningning

2013-10-01

This study describes a simple and highly selective method for the colorimetric detection of trivalent chromium (Cr3+) using tartrate-capped silver nanoparticles (AgNPs) as probe. The addition of tartrate to the initially prepared AgNPs gives tartrate-stabilized AgNPs ascribing to the electrostatic repulsion of the highly negatively charged tartrate ions covered on the surface of AgNPs. It is found that, in the presence of Cr3+ in aqueous solution, the aggregation of tartrate-stabilized AgNPs occurs. The color of AgNPs suspension changes from yellow to pink and the surface plasmon absorption band broadens and red shifts, which could be applied for the colorimetric detection of Cr3+ in aqueous solution. The utilization of tartrate-stabilized AgNPs as probe substantially increases the selectivity and sensitivity for colorimetric detection of Cr3+. Control experiments with the addition of over 14 other metal ions, such as Pb2+, Zn2+, Cr2O7(2-), Cd2+, Co2+, Cu2+, Al3+, Ni2+, Mn2+, Ba2+, Fe3+, Ca2+, Mg2+, Sr+ do not result in a distinct change in the color or in the spectrum of the suspension, indicating that these metal ions do not interfere with the colorimetric detection of Cr3+. Under the conditions employed here, A502/A393 (ratio of absorption value at 502 nm to 393 nm) is linear with the concentration of Cr3+ within a concentration range from 0.1 to 1.17 microM with a detection limit of 0.06 microM. This study may offer a simple, rapid and sensitive approach to colorimetric detection of Cr3+ in aqueous solution.

Effect of mouthwash and accelerated aging on the color stability of esthetic restorative materials.

PubMed

Lee, Y K; El Zawahry, M; Noaman, K M; Powers, J M

2000-06-01

To evaluate the color stability of esthetic restorative materials after immersion in mouthwashes and accelerated aging. Compomers and resin-based composites (RBC) were measured at baseline and repeatedly after immersion in three kinds of mouthwash (Listerine, Peridex, Rembrandt Age Defying) for 24 hrs and 7 days, and after aging for 150 kJ/m2. Color was measured according to CIE L*a*b* color scale on a reflection spectrophotometer. After immersion for 7 days, the mouthwash groups did not produce significantly higher color changes than the distilled water group, except with some mouthwashes used with Tetric-Ceram. After immersion for 7 days and aging for 150 kJ/m2, the mouthwash groups did not produce significantly higher color changes than the distilled water group. Aging in weathering chamber produced color change (deltaE*) of 1.1-3.9, which was mainly influenced by the material. With some exceptions, the color changes from immersion of the RBCs and compomers in mouthwashes were not perceptible (deltaE*<3.3).

Difference in the color stability of direct and indirect resin composites

PubMed Central

LEE, Yong-Keun; YU, Bin; LIM, Ho-Nam; LIM, Jin Ik

2011-01-01

Indirect resin composites are generally regarded to have better color stability than direct resin composites since they possess higher conversion degree Objective The present study aimed at comparing the changes in color (∆E) and color coordinates (∆L, ∆a and ∆b) of one direct (Estelite Sigma: 16 shades) and 2 indirect resin composites (BelleGlass NG: 16 shades; Sinfony: 26 shades) after thermocycling. Material and Methods Resins were packed into a mold and light cured; post-curing was performed on indirect resins. Changes in color and color coordinates of 1-mm-thick specimens were determined after 5,000 cycles of thermocycling on a spectrophotometer. Results ∆E values were in the range of 0.3 to 1.2 units for direct resins, and 0.3 to 1.5 units for indirect resins, which were clinically acceptable (∆E<3.3). Based on t-test, ∆E values were not significantly different by the type of resins (p>0.05), while ∆L, ∆a and ∆b values were significantly different by the type of resins (p<0.05). For indirect resins, ∆E values were influenced by the brand, shade group and shade designation based on three-way ANOVA (p<0.05). Conclusion Direct and indirect resin composites showed similar color stability after 5,000 cycles of thermocycling; however, their changes in the color coordinates were different. PMID:21552717

Color stability of microfilled, microhybrid and nanocomposite resins--an in vitro study.

PubMed

Nasim, Iffat; Neelakantan, Prasanna; Sujeer, R; Subbarao, C V

2010-01-01

The aim of this study was to evaluate the effect of two beverages-Tea and Pepsi on the color stability of three different composite resins after a period of 7 and 30 days. Color stability of a microfilled, microhybrid and nanocomposite was evaluated after storage in Tea, a carbonated drink or Distilled Water for 7 and 30 days. Color measurement was done using reflectance spectrophotometer based on the CIE L*a*b* color scale. Mean values of the different groups were compared using three-way analysis of variance and multiple comparisons of the mean values were done using Tukey-Kramer test with 0.05 as significance level. All tested resin composites showed color change after a period of 7 and 30 days. The color change exhibited by all three groups was significantly different for all three beverages studied, at both time periods (p<0.05). Amongst the resin composites studied microhybrid composite was found to be more color stable. The microfilled composite discolored most in Distilled Water and Pepsi at the 7th and 30th day. The nanocomposite discolored most in Tea at 7th and 30th day. All efforts should be made to minimize discoloration of composite restorations by adopting excellent polishing techniques. Patients should also be educated on the possibility of the restoration to undergo staining under the influence of beverages. Copyright © 2010 Elsevier Ltd. All rights reserved.

Effects of short-term immersion and brushing with different denture cleansers on the roughness, hardness, and color of two types of acrylic resin.

PubMed

Panariello, Beatriz Helena Dias; Izumida, Fernanda Emiko; Moffa, Eduardo Buozi; Pavarina, Ana Claudia; Jorge, Janaina Habib; Giampaolo, Eunice Teresinha

2015-06-01

To investigate the cumulative effects of brushing (B) or immersion (I), using different cleansing agents, on the surface roughness, hardness and color stability of a heat-polymerized denture resin, Lucitone 550 (L), and a hard chairside reline resin, Tokuyama Rebase Fast II (T). A total of 316 specimens (10 x 2 mm) were fabricated. The specimens (n = 9) were divided into brushing or immersion groups according to the following agents: dentifrice/distilled water (D), 1% sodium hypochlorite (NaOCl), Corega Tabs (Pb), 1% chlorhexidine gluconate (Chx), and 0.2% peracetic acid (Ac). Brushing and immersion were tested independently. Assays were performed after 1, 3, 21, 45 and 90 brushing cycles or immersion of 10 seconds each. Data were evaluated statistically by repeated measures ANOVA. Tukey's honestly significant difference (HSD) post-hoc test was used to determine differences between means (α = 0.05). For L there was no statistically significant difference in roughness, except a significant decrease in roughness by brushing with D. T showed a significant effect on the roughness after 90 immersions with Ac. Hardness values decreased for L when specimens were immersed or brushed in NaOCl and Pb. The hardness of T decreased with increases in the repetitions (immersion or brushing), regardless of the cleaning method. Values of color stability for L resin showed significant color change after brushing with and immersion in Ac and Pb. Brushing with D exhibited a higher incidence of color change. For T there were no significant differences between cleaning agents and repetitions in immersion. A color change was noted after three brushings with the Ac, Chx, and D. Brushing with dentifrice decreased roughness of L. Immersion in or brushing with NaOCl and Pb decreased the hardness of L. For T, hardness decreased with increases in immersions or brushing. Color changes after the immersion in or brushing with cleaning agents were clinically acceptable according to National Bureau of Standards parameters for both resins.

Simple single-emitting layer hybrid white organic light emitting with high color stability

NASA Astrophysics Data System (ADS)

Nguyen, C.; Lu, Z. H.

2017-10-01

Simultaneously achieving a high efficiency and color quality at luminance levels required for solid-state lighting has been difficult for white organic light emitting diodes (OLEDs). Single-emitting layer (SEL) white OLEDs, in particular, exhibit a significant tradeoff between efficiency and color stability. Furthermore, despite the simplicity of SEL white OLEDs being its main advantage, the reported device structures are often complicated by the use of multiple blocking layers. In this paper, we report a highly simplified three-layered white OLED that achieves a low turn-on voltage of 2.7 V, an external quantum efficiency of 18.9% and power efficiency of 30 lm/W at 1000 cd/cm2. This simple white OLED also shows good color quality with a color rendering index of 75, CIE coordinates (0.42, 0.46), and little color shifting at high luminance. The device consists of a SEL sandwiched between a hole transport layer and an electron transport layer. The SEL comprises a thermally activated delayer fluorescent molecule having dual functions as a blue emitter and as a host for other lower energy emitters. The improved color stability and efficiency in such a simple device structure is explained as due to the elimination of significant energy barriers at various organic-organic interfaces in the traditional devices having multiple blocking layers.

Effect of bleaching on color stability and roughness of composite resins aged in staining beverage.

PubMed

Rodrigues, Camila Silva; Mozzaquatro, Lisandra Rossato; Dala Nora, Bárbara; Jacques, Letícia Borges; Mallmann, André

2017-01-01

Composite resin properties can be affected by contact with gel during bleaching procedures; however, there is no consensus about the effect of this contact on resin susceptibility to color change. This study aimed to evaluate staining susceptibility and surface roughness changes in 2 composite resins (Filtek Z250 XT and Filtek Z350 XT) after application of bleaching peroxides and storage in different media. Forty-two disc-shaped specimens of each composite were made, polished, and divided into 3 groups according to treatment type (35% hydrogen peroxide, 16% carbamide peroxide, or deionized water as a control group). These groups were subdivided into 2 groups according to immersion media (n = 7): deionized water or red wine. Color and average roughness (Ra) measurements were taken 24 hours after specimen preparation (T0), immediately after bleaching procedures (T1), and immediately after aging (staining; T2). Statistical analyses were performed using 2-way analyses of variance for repeated measurements and the Tukey test (P < 0.05). Bleaching resulted in minimal color change (ΔE* < 1) in all groups. Filtek Z350 XT specimens presented greater mean values of color change. The Ra values did not increase significantly after bleaching procedures or aging (staining) in all groups. Thus, bleaching agents did not significantly change the color or roughness of the composite resins used in this study.

Categorical color constancy for simulated surfaces.

PubMed

Olkkonen, Maria; Hansen, Thorsten; Gegenfurtner, Karl R

2009-11-12

Color constancy is the ability to perceive constant surface colors under varying lighting conditions. Color constancy has traditionally been investigated with asymmetric matching, where stimuli are matched over two different contexts, or with achromatic settings, where a stimulus is made to appear gray. These methods deliver accurate information on the transformations of single points of color space under illuminant changes, but can be cumbersome and unintuitive for observers. Color naming is a fast and intuitive alternative to matching, allowing data collection from a large portion of color space. We asked observers to name the colors of 469 Munsell surfaces with known reflectance spectra simulated under five different illuminants. Observers were generally as consistent in naming the colors of surfaces under different illuminants as they were naming the colors of the same surfaces over time. The transformations in category boundaries caused by illuminant changes were generally small and could be explained well with simple linear models. Finally, an analysis of the pattern of naming consistency across color space revealed that largely the same hues were named consistently across illuminants and across observers even after correcting for category size effects. This indicates a possible relationship between perceptual color constancy and the ability to consistently communicate colors.

Ultrastable, highly luminescent quantum dot composites based on advanced surface manipulation strategy for flexible lighting-emitting.

PubMed

Kong, Lingqing; Zhang, Lin; Meng, Zhaohui; Xu, Chuan; Lin, Naibo; Liu, Xiang-Yang

2018-08-03

Although quantum dots (QDs) have remarkable potential application in flexible light emitting diodes (LED), the loss of solvent-protected QDs leads to low quantum yield (QY) and poor stability, severely restricting the development. Flexible QD LEDs (Q-LEDs) with three primary colors were fabricated by mixing CdS/ZnS, CdSe@ZnS/ZnS, and CdSe/CdS QDs with polydimethylsiloxane (PDMS) by in situ hydrosilylation based surface manipulation strategy, which endows the device with highly ultrastable and luminescent performance. The surface manipulation strategy mainly includes the control of solvent dosage, purification times of QDs, concentration of QDs in PDMS, and oxidation on the preparation process of the QDs and PDMS composites. The highest QY of CdSe@ZnS/ZnS-PDMS composite is 82.03%, higher than the QY (80%) of the QD solution. After UV bleaching, organic solvents (acetone, ethanol and water), and heating treatment, the QYs of the QDs and PDMS maintain a high value, manifesting their good stability. Q-LED hybrid light-emitting devices were further fabricated by a molding technique demonstrating satisfied current and thermal stability. Flexible Q-LEDs can be expended to other shapes, such as fibers and blocks, indicating the huge potential of QD-polymer composites for light sources and displays etc.

Sample-Based Surface Coloring

PubMed Central

Bürger, Kai; Krüger, Jens; Westermann, Rüdiger

2011-01-01

In this paper, we present a sample-based approach for surface coloring, which is independent of the original surface resolution and representation. To achieve this, we introduce the Orthogonal Fragment Buffer (OFB)—an extension of the Layered Depth Cube—as a high-resolution view-independent surface representation. The OFB is a data structure that stores surface samples at a nearly uniform distribution over the surface, and it is specifically designed to support efficient random read/write access to these samples. The data access operations have a complexity that is logarithmic in the depth complexity of the surface. Thus, compared to data access operations in tree data structures like octrees, data-dependent memory access patterns are greatly reduced. Due to the particular sampling strategy that is employed to generate an OFB, it also maintains sample coherence, and thus, exhibits very good spatial access locality. Therefore, OFB-based surface coloring performs significantly faster than sample-based approaches using tree structures. In addition, since in an OFB, the surface samples are internally stored in uniform 2D grids, OFB-based surface coloring can efficiently be realized on the GPU to enable interactive coloring of high-resolution surfaces. On the OFB, we introduce novel algorithms for color painting using volumetric and surface-aligned brushes, and we present new approaches for particle-based color advection along surfaces in real time. Due to the intermediate surface representation we choose, our method can be used to color polygonal surfaces as well as any other type of surface that can be sampled. PMID:20616392

Morphology and pH changes in leached solidified/stabilized waste forms

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cheng, K.Y.; Bishop, P.L.

1996-12-31

Leaching of cement-based waste forms in acetic acid solutions with different acidic strengths has been investigated in this work. The examination of the morphology and pH profile along the acid penetration route by an optical microscope and various pH color indicators is reported. A clear-cut leaching boundary, where the pH changes from below 6 in the leached surface layers to above 12 in the unleached waste form, was observed in every leached sample.

No Measured Effect of a Familiar Contextual Object on Color Constancy.

PubMed

Kanematsu, Erika; Brainard, David H

2014-08-01

Some familiar objects have a typical color, such as the yellow of a banana. The presence of such objects in a scene is a potential cue to the scene illumination, since the light reflected from them should on average be consistent with their typical surface reflectance. Although there are many studies on how the identity of an object affects how its color is perceived, little is known about whether the presence of a familiar object in a scene helps the visual system stabilize the color appearance of other objects with respect to changes in illumination. We used a successive color matching procedure in three experiments designed to address this question. Across the experiments we studied a total of 6 subjects (2 in Experiment 1, 3 in Experiment 2, and 4 in Experiment 3) with partial overlap of subjects between experiments. We compared measured color constancy across conditions in which a familiar object cue to the illuminant was available with conditions in which such a cue was not present. Overall, our results do not reveal a reliable improvement in color constancy with the addition of a familiar object to a scene. An analysis of the experimental power of our data suggests that if there is such an effect, it is small: less than approximately a change of 0.09 in a constancy index where an absence of constancy corresponds to an index value of 0 and perfect constancy corresponds to an index value of 1.

No Measured Effect of a Familiar Contextual Object on Color Constancy

PubMed Central

Kanematsu, Erika; Brainard, David H.

2013-01-01

Some familiar objects have a typical color, such as the yellow of a banana. The presence of such objects in a scene is a potential cue to the scene illumination, since the light reflected from them should on average be consistent with their typical surface reflectance. Although there are many studies on how the identity of an object affects how its color is perceived, little is known about whether the presence of a familiar object in a scene helps the visual system stabilize the color appearance of other objects with respect to changes in illumination. We used a successive color matching procedure in three experiments designed to address this question. Across the experiments we studied a total of 6 subjects (2 in Experiment 1, 3 in Experiment 2, and 4 in Experiment 3) with partial overlap of subjects between experiments. We compared measured color constancy across conditions in which a familiar object cue to the illuminant was available with conditions in which such a cue was not present. Overall, our results do not reveal a reliable improvement in color constancy with the addition of a familiar object to a scene. An analysis of the experimental power of our data suggests that if there is such an effect, it is small: less than approximately a change of 0.09 in a constancy index where an absence of constancy corresponds to an index value of 0 and perfect constancy corresponds to an index value of 1. PMID:25313267

Lithographically Encrypted Inverse Opals for Anti-Counterfeiting Applications.

PubMed

Heo, Yongjoon; Kang, Hyelim; Lee, Joon-Seok; Oh, You-Kwan; Kim, Shin-Hyun

2016-07-01

Colloidal photonic crystals possess inimitable optical properties of iridescent structural colors and unique spectral shape, which render them useful for security materials. This work reports a novel method to encrypt graphical and spectral codes in polymeric inverse opals to provide advanced security. To accomplish this, this study prepares lithographically featured micropatterns on the top surface of hydrophobic inverse opals, which serve as shadow masks against the surface modification of air cavities to achieve hydrophilicity. The resultant inverse opals allow rapid infiltration of aqueous solution into the hydrophilic cavities while retaining air in the hydrophobic cavities. Therefore, the structural color of inverse opals is regioselectively red-shifted, disclosing the encrypted graphical codes. The decoded inverse opals also deliver unique reflectance spectral codes originated from two distinct regions. The combinatorial code composed of graphical and optical codes is revealed only when the aqueous solution agreed in advance is used for decoding. In addition, the encrypted inverse opals are chemically stable, providing invariant codes with high reproducibility. In addition, high mechanical stability enables the transfer of the films onto any surfaces. This novel encryption technology will provide a new opportunity in a wide range of security applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Natural pigments: carotenoids, anthocyanins, and betalains--characteristics, biosynthesis, processing, and stability.

PubMed

Delgado-Vargas, F; Jiménez, A R; Paredes-López, O

2000-05-01

Pigments are present in all living matter and provide attractive colors and play basic roles in the development of organisms. Human beings, like most animals, come in contact with their surroundings through color, and things can or cannot be acceptable based on their color characteristics. This review presents the basic information about pigments focusing attention on the natural ones; it emphasizes the principal plant pigments: carotenoids, anthocyanins, and betalains. Special considerations are given to their salient characteristics; to their biosynthesis, taking into account the biochemical and molecular biology information generated in their elucidation; and to the processing and stability properties of these compounds as food colorants.

Color stabilization of porcine hemoglobin during spray-drying and powder storage by combining chelating and reducing agents.

PubMed

Salvador, P; Toldrà, M; Parés, D; Carretero, C; Saguer, E

2009-10-01

This work focuses on the effects of adding a chelating agent - such as nicotinic acid (NA, 2% w/v) or nicotinamide (Nam, 2.5% w/v) - along with glucose as a reducing agent (G, 10% w/v) to fresh porcine hemoglobin in order to stabilize its red color during spray-drying and powder storage at room temperature. Correlations between the CIELAB color parameters and the relative percentages of the different hemoglobin derivatives (liganded and deliganded ferrohemoglobin, and methemoglobin) were analyzed. The results indicate that, although little effects could be observed for any of the combined treatments on fresh hemoglobin, they were effective against pigment autoxidation during dehydration and subsequent storage. From the results, it can also be concluded that glucose was the main contributor to the color stabilization of the hemoglobin powder, probably due to its high water retention capacity.

Color stabilization of red wines. A chemical and colloidal approach.

PubMed

Alcalde-Eon, Cristina; García-Estévez, Ignacio; Puente, Victor; Rivas-Gonzalo, Julián C; Escribano-Bailón, M Teresa

2014-07-23

The effects of cold treatment and time on CIELAB color parameters and on anthocyanin and anthocyanin-derived pigments composition have been evaluated as has been the effectiveness of either an enological tannin or a mannoprotein (M) on their stabilization. With respect to color, hue (hab) was increased in the wines treated with both enological products. Furthermore, the color changes induced by cold treatment were lessened by the addition of these two enological products, although the protective effect was higher for the wines treated with M. The pigment analysis revealed higher percentages of anthocyanin-derived pigments in tannin and M-treated samples (in both cold treated and not) in relation to control ones. The addition of the enological tannin may favor the synthesis of anthocyanin-derived pigments, which are chemically more stable than native anthocyanins, whereas M seems to stabilize anthocyanin-derived pigments from a colloidal point of view, avoiding their aggregation and further precipitation.

Continuous hierarchical slope-aspect color display for parametric surfaces

NASA Technical Reports Server (NTRS)

Moellering, Harold J. (Inventor); Kimerling, A. Jon (Inventor)

1994-01-01

A method for generating an image of a parametric surface, such as the aspect of terrain which maximizes color contrast to permit easy discrimination of the magnitude, ranges, intervals or classes of a surface parameter while making it easy for the user to visualize the form of the surface, such as a landscape. The four pole colors of the opponent process color theory are utilized to represent intervals or classes at 90 degree angles. The color perceived as having maximum measured luminance is selected to portray the color having an azimuth of an assumed light source and the color showing minimum measured luminance portrays the diametrically opposite azimuth. The 90 degree intermediate azimuths are portrayed by unique colors of intermediate measured luminance, such as red and green. Colors between these four pole colors are used which are perceived as mixtures or combinations of their bounding colors and are arranged progressively between their bounding colors to have perceived proportional mixtures of the bounding colors which are proportional to the interval's angular distance from its bounding colors.

Scanning Electron Microscopy Findings With Energy-Dispersive X-ray Investigations of Cosmetically Tinted Contact Lenses

PubMed Central

Hotta, Fumika; Imai, Shoji; Miyamoto, Tatsuro; Mitamura-Aizawa, Sayaka; Mitamura, Yoshinori

2015-01-01

Objective: To investigate the surfaces and principal elements of the colorants of cosmetically tinted contact lenses (Cos-CLs). Methods: We analyzed the surfaces and principal elements of the colorants of five commercially available Cos-CLs using scanning electron microscopy with energy-dispersive x-ray analysis. Results: In two Cos-CLs, the anterior and posterior surfaces were smooth, and colorants were found inside the lens. One lens showed colorants located to a depth of 8 to 14 μm from the anterior side of the lens. In the other lens, colorants were found in the most superficial layer on the posterior surface, although a coated layer was observed. The colorants in the other three lenses were deposited on either lens surface. Although a print pattern was uniform in embedded type lenses, uneven patterns were apparent in dot-matrix design lenses. Colorants used in all lenses contained chlorine, iron, and titanium. In the magnified scanning electron microscopy images of a certain lens, chlorine is exuded and spread. Conclusions: Cosmetically tinted contact lenses have a wide variety of lens surfaces and colorants. Colorants may be deposited on the lens surface and consist of an element that has tissue toxicity. PMID:25799458

Memory color of natural familiar objects: effects of surface texture and 3-D shape.

PubMed

Vurro, Milena; Ling, Yazhu; Hurlbert, Anya C

2013-06-28

Natural objects typically possess characteristic contours, chromatic surface textures, and three-dimensional shapes. These diagnostic features aid object recognition, as does memory color, the color most associated in memory with a particular object. Here we aim to determine whether polychromatic surface texture, 3-D shape, and contour diagnosticity improve memory color for familiar objects, separately and in combination. We use solid three-dimensional familiar objects rendered with their natural texture, which participants adjust in real time to match their memory color for the object. We analyze mean, accuracy, and precision of the memory color settings relative to the natural color of the objects under the same conditions. We find that in all conditions, memory colors deviate slightly but significantly in the same direction from the natural color. Surface polychromaticity, shape diagnosticity, and three dimensionality each improve memory color accuracy, relative to uniformly colored, generic, or two-dimensional shapes, respectively. Shape diagnosticity improves the precision of memory color also, and there is a trend for polychromaticity to do so as well. Differently from other studies, we find that the object contour alone also improves memory color. Thus, enhancing the naturalness of the stimulus, in terms of either surface or shape properties, enhances the accuracy and precision of memory color. The results support the hypothesis that memory color representations are polychromatic and are synergistically linked with diagnostic shape representations.

Structural coloration of metallic surfaces with micro/nano-structures induced by elliptical vibration texturing

NASA Astrophysics Data System (ADS)

Yang, Yang; Pan, Yayue; Guo, Ping

2017-04-01

Creating orderly periodic micro/nano-structures on metallic surfaces, or structural coloration, for control of surface apparent color and optical reflectivity has been an exciting research topic over the years. The direct applications of structural coloration include color marking, display devices, and invisibility cloak. This paper presents an efficient method to colorize metallic surfaces with periodic micro/nano-gratings using elliptical vibration texturing. When the tool vibration is coupled with a constant cutting velocity, controlled periodic ripples can be generated due to the overlapping tool trajectory. These periodic ripples with a wavelength near visible spectrum can act as micro-gratings to introduce iridescent colors. The proposed technique also provides a flexible method for color marking of metallic surfaces with arbitrary patterns and images by precise control of the spacing distance and orientation of induced micro/nano-ripples. Theoretical analysis and experimental results are given to demonstrate structural coloration of metals by a direct mechanical machining technique.

Visual and surface plasmon resonance sensor for zirconium based on zirconium-induced aggregation of adenosine triphosphate-stabilized gold nanoparticles.

PubMed

Qi, Wenjing; Zhao, Jianming; Zhang, Wei; Liu, Zhongyuan; Xu, Min; Anjum, Saima; Majeed, Saadat; Xu, Guobao

2013-07-17

Owing to its high affinity with phosphate, Zr(IV) can induce the aggregation of adenosine 5'-triphosphate (ATP)-stabilized AuNPs, leading to the change of surface plasmon resonance (SPR) absorption spectra and color of ATP-stabilized AuNP solutions. Based on these phenomena, visual and SPR sensors for Zr(IV) have been developed for the first time. The A(660 nm)/A(518 nm) values of ATP-stabilized AuNPs in SPR absorption spectra increase linearly with the concentrations of Zr(IV) from 0.5 μM to 100 μM (r=0.9971) with a detection limit of 95 nM. A visual Zr(IV) detection is achieved with a detection limit of 30 μM. The sensor shows excellent selectivity against other metal ions, such as Cu(2+), Fe(3+), Cd(2+), and Pb(2+). The recoveries for the detection of 5 μM, 10 μM, 25 μM and 75 μM Zr(IV) in lake water samples are 96.0%, 97.0%, 95.6% and 102.4%, respectively. The recoveries of the proposed SPR method are comparable with those of ICP-OES method. Copyright © 2013 Elsevier B.V. All rights reserved.

Uncertainty of sensory signal explains variation of color constancy.

PubMed

Witzel, Christoph; van Alphen, Carlijn; Godau, Christoph; O'Regan, J Kevin

2016-12-01

Color constancy is the ability to recognize the color of an object (or more generally of a surface) under different illuminations. Without color constancy, surface color as a perceptual attribute would not be meaningful in the visual environment, where illumination changes all the time. Nevertheless, it is not obvious how color constancy is possible in the light of metamer mismatching. Surfaces that produce exactly the same sensory color signal under one illumination (metamerism) may produce utterly different sensory signals under another illumination (metamer mismatching). Here we show that this phenomenon explains to a large extent the variation of color constancy across different colors. For this purpose, color constancy was measured for different colors in an asymmetric matching task with photorealistic images. Color constancy performance was strongly correlated to the size of metamer mismatch volumes, which describe the uncertainty of the sensory signal due to metamer mismatching for a given color. The higher the uncertainty of the sensory signal, the lower the observers' color constancy. At the same time, sensory singularities, color categories, and cone ratios did not affect color constancy. The present findings do not only provide considerable insight into the determinants of color constancy, they also show that metamer mismatch volumes must be taken into account when investigating color as a perceptual property of objects and surfaces.

Current Developments in Colour Microform Technology.

ERIC Educational Resources Information Center

Gunn, Michael J.

1985-01-01

Addresses some lingering problems with production and use of color microforms, e.g., reliable microfilm emulsion, color temperature, and image fading; and reports on recent advances in color stability and accuracy and international efforts to standardize production. (MBR)

Study on the fabrication of composite photonic crystals with high structural stability by co-sedimentation self-assembly on fabric substrates

NASA Astrophysics Data System (ADS)

Li, Yichen; Zhou, Lan; Liu, Guojin; Chai, Liqin; Fan, Qinguo; Shao, Jianzhong

2018-06-01

The Silica/Poly(methylmethacrylate-butylacrylate)[SiO2/P(MMA-BA)] photonic crystals(PCs) with brilliant structural colors were fabricated on fabric substrates by co-sedimentation self-assembly, in which the relatively smaller P(MMA-BA) copolymer particles filled in the interstices among the larger SiO2 microspheres. The fabricated composite PCs were mechanically robust and strongly bonded to the substrate because of the cementing effect caused by the soft P(MMA-BA) copolymer particles filling in the interstices of the SiO2 microspheres like cement filling in the gap and tightly holding stones in a sturdy cement wall. The volume fraction and the size ratios of the two components significantly influenced the structural colors of the composite PCs, and the larger volume fraction could improve the structural stability of the composite PCs, while the smaller size ratios could enhance the brightness of the structural colors of the composite PCs. The composite PCs with both high structural stability and brilliant structural colors have great application prospect for structural coloration of textiles.

Locality-preserving logical operators in topological stabilizer codes

NASA Astrophysics Data System (ADS)

Webster, Paul; Bartlett, Stephen D.

2018-01-01

Locality-preserving logical operators in topological codes are naturally fault tolerant, since they preserve the correctability of local errors. Using a correspondence between such operators and gapped domain walls, we describe a procedure for finding all locality-preserving logical operators admitted by a large and important class of topological stabilizer codes. In particular, we focus on those equivalent to a stack of a finite number of surface codes of any spatial dimension, where our procedure fully specifies the group of locality-preserving logical operators. We also present examples of how our procedure applies to codes with different boundary conditions, including color codes and toric codes, as well as more general codes such as Abelian quantum double models and codes with fermionic excitations in more than two dimensions.

Disruptive Effects of Colorful vs. Non-colorful Play Area on Structured Play-A Pilot Study with Preschoolers.

PubMed

Stern-Ellran, Keren; Zilcha-Mano, Sigal; Sebba, Rachel; Levit Binnun, Nava

2016-01-01

To contribute to young children's development, sensory enrichment is often provided via colorful play areas. However, little is known about the effects of colorful environments on children while they engage in age-appropriate tasks and games. Studies in adults suggest that aspects of color can distract attention and impair performance, and children are known to have less developed attentional and executive abilities than adults. Preliminary studies conducted in children aged 5-8 suggest that the colorfulness of both distal (e.g., wall decorations) and proximal (e.g., the surface of the desktop) environments can have a disruptive effect on children's performance. The present research seeks to extend the previous studies to an even younger age group and focus on proximal colorfulness. With a sample of 15 pre-schoolers (3-4 years old) we examined whether a colorful play surface compared to a non-colorful (white) play surface would affect engagement in developmentally appropriate structured play. Our pilot findings suggest that a colorful play surface interfered with preschoolers' structured play, inducing more behaviors indicating disruption in task execution compared with a non-colorful play surface. The implications of the current study for practice and further research are discussed.

Effect of enamel sealants on tooth bleaching and on the color stability of the result.

PubMed

Corcodel, N; Hassel, A J; Sen, S; Saure, D; Rammelsberg, P; Lux, C J; Zingler, S

2017-04-01

The purpose of this in vitro study was to evaluate the effect of enamel sealants on bleaching of natural teeth by use of 40 % hydrogen peroxide in a dental surgery. The color stability of the results from bleaching was, furthermore, determined 10 months after the bleaching procedure. In a standardized setting, four sealants (Pro Seal ® , Light Bond™ Sealant, Protecto ® , and Clinpro™ XT Varnish) were applied to and removed from human teeth in accordance with the manufacturer's instructions. Natural teeth served as medium; half of the teeth were sealed and the others served as controls. Hydrogen peroxide gel (40 %; Opalescence Boost; Ultradent Products, South Jordan, UT, USA) was used as bleaching agent. Color measurement was performed with a spectroradiometer (Photoresearch PR670) before the bleaching process (T1) and 24 h (T2) and 10 months (T3) after bleaching. The spectroradiometer results were expressed by use of the Commission Internationale de l'Éclairage (CIE) L*a*b* color notation. The L*, a*, and b* values of the sealed and the unsealed surfaces were not significantly different at any time during the study (p > 0.05), irrespective of the sealant used. Ten months after the bleaching process, mean L*, a*, and b* values were lower than at 1-day post-bleaching; the mean value of ΔE between 1-day post-bleaching and 10 months post-bleaching was 2.46 (±3.1). The results of the study suggest that the effectiveness of professional tooth whitening is not appreciably affected by the application of the four sealants tested.

Influence of composite type and light irradiance on color stability after immersion in different beverages.

PubMed

Alberton Da Silva, Victória; Alberton Da Silva, Simone; Pecho, Oscar E; Bacchi, Atais

2018-06-19

The aim of this study was to evaluate the color stability of two resin-based composites photo-activated by two light curing units (LCU) with different irradiances. Hundred disc-shaped specimens (2-mm thick) of a nanofilled (FZ- Filtek TM Z350 XT, 3M ESPE) and a microhybrid (ED-Empress ® Direct, Ivoclar Vivadent) composites were photo-activated with two LCU: Valo ® Cordless, Ultradent (VA-1800 mW/cm 2 ) or Radii-cal, SDI (RA-900 mW/cm 2 ). Samples (n = 5) were immersed during 12 days in distilled water (WT), orange juice (OJ), red wine (RW), coffee (CF), or Brazilian tea (BT). CIELAB coordinates were obtained using a spectrophotometer (Easyshade 4.0, Vita Zahnfabrik) before (T 0 ) and after (T 1 ) immersion. CIEDE2000 color difference (ΔE 00 ) and whiteness index for dentistry (WI D ) were calculated. Data was analyzed by two-way ANOVA and Tukey's test (α = 0.05%). FZ light-activated by VA showed higher L* and WI D values (T 0 ) and lower ΔE 00 values after immersion in WT, OJ, and RW. However, there was no effect of both factors on ΔE 00 when samples were immersed in BT and CF. ED light-activated by RA showed significant higher C* values (p ≤ .05). The nanofilled composite photo-activated with higher irradiance showed greater L* and WI D values and better color stability. However, all samples immersed in colored beverages showed ΔE 00 values above the acceptability threshold. Initial color of resin-based composites can change after immersion in staining beverages. However, the best color stability was obtained by the nanocomposite photo-activated by a light-curing unit of higher irradiance. © 2018 Wiley Periodicals, Inc.

Effect of different polishing systems and drinks on the color stability of resin composite.

PubMed

Berber, Asll; Cakir, Filiz Yalcin; Baseren, Meserret; Gurgan, Sevil

2013-07-01

The purpose of this study was to evaluate the color stability of resin composit using different finishing systems and drinks. Composit disks (5 mm diameter, 2 mm thickness) were prepared for each nanofilled composite using a brass mold. The specimens were divided into 5 finishing system groups Mylar strip (Mylar, DuPont, Wilmington, Del., USA), Soft Lex (3M(™) ESPE(™) St. Paul, MN, USA), Enhance (Dentsply-DeTrey GmbHD Konstanz, Germany), Hiluster (KerrHawe, Bioggio, Switzerland), Opti Disc (KerrHawe, Bioggio, Switzerland) and each group was divided into 10 subgroups (n = 10) and stored for 24 hours at 37°C in different drinks water coffee, coffee with sugar, tea, tea with sugar, diet coke, coke, light sour cherry juice or sour cherry juice. Color of all specimens was measured before and after exposure with a spectrophotometer using CIE L*a*b* relative, and color changes (ΔE*) were then calculated. The data were analyzed with a twoway analysis of variance (ANOVA), and mean values were compared by the Tukey HSD test (p = 0.05). For the drinks, the lowest ΔE* values were observed in the water and highest ΔE* values were observed in sour cherry juice. When drinks with and without sugar were compared, all groups with sugar demonstrated a higher color difference than without sugar. For the different finishing systems, Mylar strip group demonstrated significantly highest color change; Enhance groups demonstrated significantly lowest color change. Finishing treatments and storage solutions significantly affect the color stability of resin composite. The presence of sugar in drinks increased the color difference compared to drinks without composit. Polishing techniques and drinking drinks with sugar may affect the color of esthetic restorations.

Influence of whitening and regular dentifrices on orthodontic clear ligature color stability.

PubMed

Oliveira, Adauê S; Kaizer, Marina R; Salgado, Vinícius E; Soldati, Dener C; Silva, Roberta C; Moraes, Rafael R

2015-01-01

This study evaluated the effect of brushing orthodontic clear ligatures with a whitening dentifrice containing a blue pigment (Close Up White Now, Unilever, London, UK) on their color stability, when exposed to a staining agent. Ligatures from 3M Unitek (Monrovia, CA, USA) and Morelli (Sorocaba, SP, Brazil) were tested. Baseline color measurements were performed and nonstained groups (control) were stored in distilled water whereas test groups were exposed for 1 hour daily to red wine. Specimens were brushed daily using regular or whitening dentifrice. Color measurements were repeated after 7, 14, 21, and 28 days using a spectrophotometer based on the CIE L*a*b* system. Decreased luminosity (CIE L*), increased red discoloration (CIE a* axis), and increased yellow discoloration (CIE b* axis) were generally observed for ligatures exposed to the staining agent. Color variation was generally lower in specimens brushed with regular dentifrice, but ligatures brushed with whitening dentifrice were generally less red and less yellow than regular dentifrice. The whitening dentifrice led to blue discoloration trend, with visually detectable differences particularly apparent according to storage condition and ligature brand. The whitening dentifrice containing blue pigment did not improve the ligature color stability, but it decreased yellow discoloration and increased a blue coloration. The use of a whitening dentifrice containing blue pigment during orthodontic treatment might decrease the yellow discoloration of elastic ligatures. © 2015 Wiley Periodicals, Inc.

Spectral reflectance properties of minerals exposed to simulated Mars surface conditions

NASA Astrophysics Data System (ADS)

Cloutis, E. A.; Craig, M. A.; Kruzelecky, R. V.; Jamroz, W. R.; Scott, A.; Hawthorne, F. C.; Mertzman, S. A.

2008-05-01

A number of mineral species were exposed to martian surface conditions of atmospheric pressure and composition, temperature, and UV light regime, and their evolution was monitored using reflectance spectroscopy. The stabilities for different groups varied widely. Phyllosilicate spectra all showed measurable losses of interlayer H 2O, with some structural groups showing more rapid H 2O loss than others. Loss of OH from the phyllosilicates is not always accompanied by a change in metal-OH overtone absorption bands. OH-bearing sulfates, such as jarosite and alunite, show no measurable change in spectral properties, suggesting that they should be spectrally detectable on Mars on the basis of diagnostic absorption bands in the 0.4-2.5 μm region. Fe 3+- and H 2O-bearing sulfates all showed changes in the appearance and/or reduction in depths of hydroxo-bridged Fe 3+ absorption bands, particularly at 0.43 μm. The spectral changes were often accompanied by visible color changes, suggesting that subsurface sulfates exposed to the martian surface environment may undergo measurable changes in reflectance spectra and color over short periods of time (days to weeks). Organic-bearing geological materials showed no measurable change in C sbnd H related absorption bands, while carbonates and hydroxides also showed no systematic changes in spectral properties. The addition of ultraviolet irradiation did not seem to affect mineral stability or rate of spectral change, with one exception (hexahydrite). In some cases, spectral changes could be related to the formation of specific new phases. The data also suggest that hydrated minerals detected on Mars to date retain their diagnostic spectral properties that allow their unique identification.

Two-year evaluation indicates zirconia bridges acceptable alternative to PFMs.

PubMed

Perry, Ronald D; Kugel, Gerard; Sharma, Shradha; Ferreira, Susana; Magnuson, Britta

2012-01-01

The aim of this in-vivo study was to evaluate the 2-year clinical performance of zirconia computer-aided design/computer-aided manufacturing (CAD/CAM)-generated bridges. A total of 16 three- or four-unit Lava zirconia bridges were done on 15 subjects. The bridges were cemented using RelyX™ Unicem Self-Adhesive Universal Resin Cement. Evaluation was done at 6-month, 1-year, and 2-year recall visits. Evaluation criteria were color stability and matching, marginal integrity, marginal discoloration, incidence of caries, changes in restoration-tooth interface, changes in surface texture, postoperative sensitivity, maintenance of periodontal health, changes in proximal and opposing teeth, and maintenance of anatomic form. In each of these parameters, the bridges were rated in one of three possible categories: "A" (alpha)--ideal; "B" (bravo)--acceptable; and "C" (charlie)--unacceptable. After 2 years, 100% of the bridges were rated "A" for color stability and matching, marginal discoloration, incidence of caries, changes in restoration-tooth interface, changes in surface texture, postoperative sensitivity, and change in proximal or opposing teeth. In the parameter of marginal integrity, 6.25% of the bridges were rated "B;" the remaining 93.75% were rated "A." Maintenance of periodontal health was rated "B" for 6.25% of the bridges and "A" for 93.75%. At 2 years, 12.5% of the bridges rated "C" in maintenance of anatomic form and 87.5% rated "A." The overall clinical outcome was that the CAD/CAM-generated zirconia bridges were clinically acceptable.

Scalable Inkjet-Based Structural Color Printing by Molding Transparent Gratings on Multilayer Nanostructured Surfaces.

PubMed

Jiang, Hao; Kaminska, Bozena

2018-04-24

To enable customized manufacturing of structural colors for commercial applications, up-scalable, low-cost, rapid, and versatile printing techniques are highly demanded. In this paper, we introduce a viable strategy for scaling up production of custom-input images by patterning individual structural colors on separate layers, which are then vertically stacked and recombined into full-color images. By applying this strategy on molded-ink-on-nanostructured-surface printing, we present an industry-applicable inkjet structural color printing technique termed multilayer molded-ink-on-nanostructured-surface (M-MIONS) printing, in which structural color pixels are molded on multiple layers of nanostructured surfaces. Transparent colorless titanium dioxide nanoparticles were inkjet-printed onto three separate transparent polymer substrates, and each substrate surface has one specific subwavelength grating pattern for molding the deposited nanoparticles into structural color pixels of red, green, or blue primary color. After index-matching lamination, the three layers were vertically stacked and bonded to display a color image. Each primary color can be printed into a range of different shades controlled through a half-tone process, and full colors were achieved by mixing primary colors from three layers. In our experiments, an image size as big as 10 cm by 10 cm was effortlessly achieved, and even larger images can potentially be printed on recombined grating surfaces. In one application example, the M-MIONS technique was used for printing customizable transparent color optical variable devices for protecting personalized security documents. In another example, a transparent diffractive color image printed with the M-MIONS technique was pasted onto a transparent panel for overlaying colorful information onto one's view of reality.

Potential mechanisms of carbon monoxide and high oxygen packaging in maintaining color stability of different bovine muscles.

PubMed

Liu, Chenglong; Zhang, Yimin; Yang, Xiaoyin; Liang, Rongrong; Mao, Yanwei; Hou, Xu; Lu, Xiao; Luo, Xin

2014-06-01

The objectives were to compare the effects of packaging methods on color stability, metmyoglobin-reducing-activity (MRA), total-reducing-activity and NADH concentration of different bovine muscles and to explore potential mechanisms in the enhanced color stability by carbon monoxide modified atmosphere packaging (CO-MAP, 0.4% CO/30% CO2/69.6% N2). Steaks from longissimus lumborum (LL), psoas major (PM) and longissimus thoracis (LT) packaged in CO-MAP, high-oxygen modified atmosphere packaging (HiOx-MAP, 80% O2/20% CO2) or vacuum packaging were stored for 0day, 4days, 9days, and 14days or stored for 9days then displayed in air for 0day, 1day, or 3days. The CO-MAP significantly increased red color stability of all muscles, and especially for PM. The PM and LT were more red than LL in CO-MAP, whereas PM had lowest redness in HiOx-MAP. The content of MetMb in CO-MAP was lower than in HiOx-MAP. Steaks in CO-MAP maintained a higher MRA compared with those in HiOx-MAP during storage. After opening packages, the red color of steaks in CO-MAP deteriorated more slowly compared with that of steaks in HiOx-MAP. Copyright © 2014 Elsevier Ltd. All rights reserved.

Luminescent properties and energy transfer of luminescent carbon dots assembled mesoporous Al(2)O(3): Eu(3) co-doped materials for temperature sensing.

PubMed

He, Youling; He, Jiangling; Zhang, Haoran; Liu, Yingliang; Lei, Bingfu

2017-06-15

Owning to the hydrogen-band interactions, blue-light-emitting luminescent carbon dots (CDs) synthesized by one-pot hydrothermal treatment were successfully assembled into Eu 3+ doped mesoporous aluminas (MAs). Interesting, dual-emissive CDs/MAs co-doped materials with higher quantum yield (QY), long-term stability, mesoporous structure, high thermal stability, and large surface areas were obtained. Furthermore, the obtained CDs/MAs co-doped materials possessed tunable color, and excellent temperature sensitivity due to the existing of energy transfer between CDs and Eu 3+ ion. The energy transfer efficiency (η) and energy transfer probability (P) for CDs/Eu 3+ co-doped materials possessed a monotonous tendency with the change of Eu 3+ content. More importantly, the dual-emissive colors can be regularly adjusted through regulating their excitation wavelength or relative mass ratio. In addition, the emission intensity of the CDs/MAs co-doped materials gradually decreased with increasing temperature showing the clear temperature dependence, this dual-emissive thermometer was with high sensitivity, owning a great fitted curve in the range from 100 to 360K under a single wavelength excitation. Copyright © 2017 Elsevier Inc. All rights reserved.

Ternary rare earth sulfide CaCe2S4: Synthesis and characterization of stability, structure, and photoelectrochemical properties in aqueous media

NASA Astrophysics Data System (ADS)

Sotelo, Paola; Orr, Melissa; Galante, Miguel Tayar; Hossain, Mohammad Kabir; Firouzan, Farinaz; Vali, Abbas; Li, Jun; Subramanian, Mas; Longo, Claudia; Rajeshwar, Krishnan; Macaluso, Robin T.

2018-06-01

A red-orange rare earth ternary chalcogenide, CaCe2S4, was prepared in powder form by solid-state synthesis. The structural details of this compound were determined by powder X-ray diffraction. The optical band gap of CaCe2S4 was determined by diffuse reflectance spectroscopy (DRS) to be 2.1 eV, consistent with the observed red-orange color. Quantitative colorimetry measurements also support the observed color and band gap of CaCe2S4. Both direct and indirect optical transitions were gleaned from Tauc analyses of the DRS data. Photoelectrochemistry experiments on CaCe2S4 films showed n-type semiconductor behavior. Analyses of these data via the Butler-Gärtner model afforded a flat-band potential of - 0.33 V (vs. Ag/AgCl/KCl 4 M) in pH 9 aqueous sulfite electrolyte. The potential and limitations of this material for solar water splitting and photocatalytic environmental remediation (e.g., dye photodegradation) are finally presented against the backdrop of its photoelectrochemical stability and surface hole transfer kinetics in aqueous electrolytes.

Color stability of nanocomposites polished with one-step systems.

PubMed

Ergücü, Zeynep; Türkün, L Sebnem; Aladag, Akin

2008-01-01

This study compared the color changes of five novel resin composites polished with two one-step polishing systems when exposed to coffee solution. The resin composites tested were Filtek Supreme XT, Grandio, CeramX, Premise and Tetric EvoCeram. A total of 150 discs (30/resin composites, 10 x 2 mm) were fabricated. Ten specimens/resin composites cured under Mylar strips served as the control. The other samples were polished with PoGo and OptraPol discs for 30 seconds using a slow speed handpiece and immersed in coffee (Nescafé) for seven days. Color measurements were made with Vita Easyshade at baseline and after one and seven days. Repeated Measures ANOVA and Bonferroni tests were used for statistical analyses (p< or =0.05). The differences between the mean DeltaE* values for the resin composites polished with two different one-step systems were statistically significant (p<0.05). After one week, all materials exhibited significant color changes compared to baseline. All Mylar finished specimens showed the most intense staining (p<0.05). There were no significant differences between the OptraPol and PoGo polished groups. Mylar-finished specimens of CeramX, Tetric EvoCeram, Premise and Filtek Supreme XT presented the greatest staining (p<0.05). For Grandio, there were no significant differences between the Mylar and PoGo groups, while the most stain resistant surfaces were attained with OptraPol. Removing the outermost resin layer by polishing procedures is essential to achieving a stain resistant, more esthetically stable surface. One-step polishing systems can be used successfully for polishing nanocomposites.

Smart textile framework: Photochromic and fluorescent cellulosic fabric printed by strontium aluminate pigment.

PubMed

Khattab, Tawfik A; Rehan, Mohamed; Hamouda, Tamer

2018-09-01

Smart clothing can be defined as textiles that respond to a certain stimulus accompanied by a change in their properties. A specific class herein is the photochromic and fluorescent textiles that change color with light. A photochromic and fluorescent cotton fabric based on pigment printing is obtained. Such fabric is prepared by aqueous-based pigment-binder printing formulation containing inorganic pigment phosphor characterized by good photo- and thermal stability. It exhibits optimal excitation wavelength (365 nm) results in color and fluorescence change of the fabric surface. To prepare the transparent pigment-binder composite film, the phosphor pigment must be well-dispersed via physical immobilization without their aggregation. The pigment-binder paste is applied successfully onto cotton fabric using screen printing technique followed by thermal fixation. After screen-printing, a homogenous photochromic film is assembled on a cotton substrate surface, which represents substantial greenish-yellow color development as indicated by CIE Lab color space measurements under ultraviolet light, even at a pigment concentration of 0.08 wt% of the printing paste. The photochromic cotton fabric exhibit three excitation peaks at 272, 325 and 365 nm and three emission peaks at 418, 495 and 520 nm. The fluorescent optical microscope, scanning electron microscope, elemental mapping, energy dispersive X-ray spectroscopy, fluorescence emission and UV/Vis absorption spectroscopic data of the printed cotton fabric are described. The printed fabric showed a reversible and rapid photochromic response during ultra-violet excitation without fatigue. The fastness properties including washing, crocking, perspiration, sublimation/heat, and light are described. Copyright © 2018 Elsevier Ltd. All rights reserved.

Investigation on stability and moisture absorption of superhydrophobic wood under alternating humidity and temperature conditions

NASA Astrophysics Data System (ADS)

Qing, Yan; Liu, Ming; Wu, Yiqiang; Jia, Shanshan; Wang, Shuang; Li, Xingong

The application of superhydrophobic wood is majorly limited by its durability when subjected to natural conditions. Herein, the stability of two representative superhydrophobic woods (i.e., Poplar (Populus tomentosa) and Chinese fir (Cunninghamia lanceolata)), were prepared via a one-step hydrothermal process using tetrabutyltitanate (Ti(OC4H9)4, TBOT) and vinyltriethoxysilane (CH2CHSi(OC2H5)3, VTES) as a co-precursor and sequentially tested under different humidity and temperature conditions. The variables including morphology, water contact angle (WCA), color parameter, chemical components of the surface, and moisture absorption property were characterized using a scanning electron microscope (SEM), WCA measurement, a colorimeter, a Fourier transform infrared (FTIR) spectroscopy, and a moisture absorption test, respectively. It was found that initial static WCAs of superhydrophobic wood were larger than 150°. Micron-sized cracks were formed on the coatings after the alternating humidity and temperature aging cycles. This lowered the water repellency, but the WCA was still greater than 140°. There was nearly no chemical change of wood after the aging test; the color change between the same species of untreated and superhydrophobic wood was very small, only with a difference of 0.42 and 4.05 in overall color change ΔE∗ values for Chinese fir and poplar, respectively. The superhydrophobic coatings had a trivial influence on wood moisture absorption property, which only lowered 3% in poplar and 2% in Chinese fir, respectively.

2,3-Pyridine dicarboxylic acid functionalized gold nanoparticles: Insight into experimental conditions for Cr3 + sensing

NASA Astrophysics Data System (ADS)

Shaikh, Ruqaya; Memon, Najma; Solangi, Amber R.; Shaikh, Huma I.; Agheem, Muhammad Hassan; Ali, Syed Abid; Shah, Muhammad Raza; Kandhro, Aftab

2017-02-01

Selectivity of gold nanoparticles (AuNPs) depends upon surface functionality; small changes in structure or concentration bring significant changes in the behavior of AuNPs. In this study, citrate-capped AuNPs were functionalized with ortho-dicarboxylate substituted pyridine (2,3-PDCA) and detailed studies on experimental conditions were carried out to check the stability of AuNPs and response for Cr3 +. Stability of PDCA-AuNPs was found sensitive to the pH, ionic strength of buffer and its type. Capping behavior of PDCA on C-AuNPs was examined by FTIR spectroscopy. Surface morphology and size of synthesized AuNPs were confirmed by AFM, XRD, and DLS techniques where particles were found 11 nm in size, monodisperse and spherical in shape. Interaction of stabilized AuNPs was tested with various metal ions; where Cr3 + induced the changes in localized surface plasmon band (LSPR) of PDCA-AuNPs which leads to a color change from wine red to violet blue. The phenomenon is explained as cooperative effect of citrate and pyridine nitrogen on surface of AuNPs in contrary to meta-dicarboxylate substituted pyridine derivatives. Further, under optimized and controlled conditions Cr3 + shows linear response with decrease in absorbance at LSPR intensity of AuNPs (518 nm). Moreover, to demonstrate the applicability of method, Cr3 + was determined in the presence of Cr (VI) which shows 96% recovery.

Jagua blue derived from Genipa americana L. fruit: A natural alternative to commonly used blue food colorants?

PubMed

Brauch, J E; Zapata-Porras, S P; Buchweitz, M; Aschoff, J K; Carle, R

2016-11-01

Due to consumers' increasing health awareness, food industry aims at replacing synthetic dyes by natural counterparts. The substitution of blue synthetic dyes is particularly challenging since current natural alternatives such as phycocyanin (Spirulina) suffer from poor stability. Jagua blue (produced from Genipa americana L. fruit) might represent a potential novel blue pigment source. However, only little is known about its color properties, and application in food systems. Therefore, the blue color and the stability of Jagua blue were assessed for the first time and compared to commonly used colorants, namely, Spirulina, brilliant blue FCF (Blue no. 1), and indigo carmine (Blue no. 2). The reaction rate of Jagua blue was independent of its concentration, confirming thermal degradation to follow first-order kinetics. Between pH 3.6 and 5.0, the color hue of Jagua blue solutions was similar to that of Blue no. 2. However, Jagua blue revealed markedly higher storage stabilities (t 1/2 =86-105days) than Blue no. 2 (t 1 /2 ≤9days) and was less susceptible to acidic pH of 3.6 (t 1 /2 =86days) than Spirulina (t 1 /2 =70days). High negative b* values (blueness) of colored gelatin gels were only obtained for Jagua blue and Spirulina, and the former exhibited higher light stabilities (t 1 /2 =15days) than Spirulina gels (t 1 /2 =4days). Our findings indicate Jagua blue to be a most promising alternative to synthetic dyes, providing relevant information regarding potential food applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Color stability of esthetic restorative materials: a spectrophotometric analysis.

PubMed

Poggio, Claudio; Ceci, Matteo; Beltrami, Riccardo; Mirando, Maria; Wassim, Jaffal; Colombo, Marco

2016-12-01

Objective: The aim of this in vitro study was to evaluate the color stability of different restorative materials (one microfilled composite, one nanofilled composite, one nanohybrid composite and one Ormocer-based composite) after exposure to different staining solutions (coffee, coca-cola and red wine). Material and methods: All materials were polymerized into silicon rings (2 mm ×6 mm ×8 mm) to obtain specimens identical in size. Thirty cylindrical specimens of each material were prepared. They were immersed in staining solutions over a 28-day test period. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. The Shapiro-Wilk test and Kruskal-Wallis ANOVA were applied to assess significant differences among restorative materials. The paired t -test was applied to test which CIE L*a*b* parameters significantly changed after immersion in staining solutions. Results: All restorative materials showed clinically perceptible color differences after immersion in coffee. L* and b* values showed the highest variability. Coca cola and red wine did not influence the color stability for all restorative materials except for Filtek Supreme XTE. Conclusions: Coffee caused a significant color change in all types of tested composite resins. Filtek Supreme XTE demonstrated alone a staining susceptibility to red wine; no other significant differences among the materials were demonstrated. Long-term exposure to some food dyes (coffee in particular) can significantly affect the color stability of modern esthetic restorative materials regardless of materials' different composition.

Coherent double-color interference microscope for traceable optical surface metrology

NASA Astrophysics Data System (ADS)

Malinovski, I.; França, R. S.; Bessa, M. S.; Silva, C. R.; Couceiro, I. B.

2016-06-01

Interference microscopy is an important field of dimensional surface metrology because it provides direct traceability of the measurements to the SI base unit definition of the metre. With a typical measurement range from micrometres to nanometres interference microscopy (IM) covers the gap between classic metrology and nanometrology, providing continuous transfer of dimensional metrology into new areas of nanoscience and nanotechnology. Therefore IM is considered to be an indispensable tool for traceable transfer of the metre unit to different instruments. We report here the metrological study of an absolute Linnik interference microscope (IM) based on two frequency stabilized lasers. The design permits the flexible use of both lasers for measurements depending on the demand of the concrete measurement task. By principle of operation IM is combination of imaging and phase-shifting interferometry (PSI). The traceability is provided by the wavelength reference, that is, a He-Ne 633 nm stabilized laser. The second laser source, that is, a Blue-Green 488 nm grating stabilized laser diode, is used for improvements of resolution, and also for resolving integer fringe discontinuities on sharp features of the surface. The IM was optimized for surface height metrology. We have performed the study of the systematic effects of the measurements. This study allowed us to improve the hardware and software of IM and to find corrections for main systematic errors. The IM is purposed for 1D to 3D height metrology and surface topography in an extended range from nanometres to micrometres. The advantages and disadvantages of the design and developed methods are discussed.

Color stability, radiopacity, and chemical characteristics of white mineral trioxide aggregate associated with 2 different vehicles in contact with blood.

PubMed

Guimarães, Bruno Martini; Tartari, Talita; Marciano, Marina Angélica; Vivan, Rodrigo Ricci; Mondeli, Rafael Francisco Lia; Camilleri, Josette; Duarte, Marco Antonio Hungaro

2015-06-01

Discoloration of mineral trioxide aggregate (MTA) can be exacerbated by the interaction of the cement with body fluids such as blood. This study aimed to analyze the color alteration, chemical characteristics, and radiopacity of MTA manipulated with 2 different vehicles after immersion in blood or distilled water (DW). MTA mixed with 100% DW or 80% DW/20% propylene glycol (PG) as vehicles were placed into rubber rings and incubated at 37°C and 100% relative humidity until set. Color assessment and scanning electron microscopy/energy-dispersive spectroscopy analysis were performed after setting and repeated after 7, 15, and 30 days after immersion in blood and DW. Statistical analysis for color alteration and radiopacity was performed using nonparametric Kruskal-Wallis and Dunn tests (P < .05). When 80% DW/20% PG was used as the vehicle, significantly lower color alterations were observed for all time periods compared with 100% DW when immersed in blood (P < .05). All surfaces displayed morphologic changes after immersion in both media because of loss of bismuth. A decrease in radiopacity was observed over time in all groups, with a statistically significant difference after 30 days for groups DW immersed in blood and 80% DW/20% immersed in both media (P < .05). The ratio of 80% DW/20% PG as a vehicle for MTA results in a lower color alteration when in contact with blood. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

Optimization of antioxidant efficacy of a deflavored and decolorized rosemary extract: effect of carnosol content on the oxidative stability of paprika colored beef patties.

PubMed

Rajeev, P S; Johannah, N M; Gopakumar, G; Maliakel, Balu; Krishnakumar, I M

2017-05-01

Considering the significance of natural antioxidants to preserve meat, the present study was undertaken to evaluate the efficacy of a deflavored and decolorised extract of rosemary (StabilRose™) for the production and preservation of naturally colored fresh meat. Oxidative rancidity of meat and color degradation of paprika oleoresin were exploited as model systems and compared with butylated hydroxyanisole (BHA). The results showed similar efficacy for 3% carnosic acid extract and BHA, with further enhancement in efficacy with respect to the carnosic acid content. A synergetic antioxidant effect of carnosol on carnosic acid content was also noticed to an extent of 1:1 (w/w) ratio, and further increase in carnosol content showed no improvement in the antioxidant efficacy. Finally, stabilized paprika and optimized rosemary extract containing carnosic acid and carnosol in 1:1 (w/w) ratio was successfully applied to produce naturally colored meat suitable for storage at 4 ± 1 °C.

Color heterogeneity of the surface of Phobos - Relationships to geologic features and comparison to meteorite analogs

NASA Technical Reports Server (NTRS)

Murchie, Scott L.; Britt, Daniel T.; Head, James W.; Pratt, Stephen F.; Fisher, Paul C.

1991-01-01

Color ratio images created from multispectral observations of Phobos are analyzed in order to characterize the spectral properties of Phobos' surface, to assess their spatial distributions and relationships with geologic features, and to compare Phobos' surface materials with possible meteorite analogs. Data calibration and processing is briefly discussed, and the observed spectral properties of Phobos and their lateral variations are examined. Attention is then given to the color properties of different types of impact craters, the origin of lateral variations in surface color, the relation between the spatial distribution of color properties and independently identifiable geologic features, and the relevance of color variation spatial distribution to the origin of the grooves.

When visual perception causes feeling: enhanced cross-modal processing in grapheme-color synesthesia.

PubMed

Weiss, Peter H; Zilles, Karl; Fink, Gereon R

2005-12-01

In synesthesia, stimulation of one sensory modality (e.g., hearing) triggers a percept in another, non-stimulated sensory modality (e.g., vision). Likewise, perception of a form (e.g., a letter) may induce a color percept (i.e., grapheme-color synesthesia). To date, the neural mechanisms underlying synesthesia remain to be elucidated. We disclosed by fMRI, while controlling for surface color processing, enhanced activity in the left intraparietal cortex during the experience of grapheme-color synesthesia (n = 9). In contrast, the perception of surface color per se activated the color centers in the fusiform gyrus bilaterally. The data support theoretical accounts that grapheme-color synesthesia may originate from enhanced cross-modal binding of form and color. A mismatch of surface color and grapheme induced synesthetically felt color additionally activated the left dorsolateral prefrontal cortex (DLPFC). This suggests that cognitive control processes become active to resolve the perceptual conflict resulting from synesthesia.

Color Stability of Heat-cure Acrylic Resin Subjected to Simulated Short-term Immersion in Fast-acting Denture Cleansers.

PubMed

Lohitha, K; Prakash, M; Gopinadh, A; Sai Sankar, A J; Sandeep, C H; Sreedevi, B

2016-01-01

Regular usage of denture cleansers is recommended in complete denture wearers for effective plaque control, and these cleansers alter the physical properties of acrylic resin over a period of time. Thus, an in vitro study was carried out to assess the effect of denture cleansers on the color stability of heat-cure denture base resin. The aim of the present study was to evaluate the effect of commercially available fast-acting denture cleansers on the color stability of heat-cure denture base resin at different time intervals. Thirty-six heat-cure acrylic resin (Ivoclar Triplex Hot-V) specimens are randomly allocated into four groups - Group A (distilled water as control); Group B (polident - 3 min); Group C (fixodent scope plus); and Group D (stain away plus) comprising of nine samples each. After recording the baseline values, the specimens were immersed in their respective cleansing solutions for a prescribed time interval. This procedure was repeated daily, and the color change (ΔE) was evaluated after 90 and 180 days interval using a colorimeter in a standard "Commission International de l'Eclairage" color system. Paired t -test and Dunnett's T3 test. All the groups exhibited a variable color change (ΔE) for an immersion period of 90 days. However, significant color differences ( P = 0.001) were noticed among the test groups after 180 days. The color change of denture base resin was greater for Group D followed by Groups B, C, and A respectively after 180 days of immersion. The ΔE values of all test groups increased with time.

Color stability of shade guides after autoclave sterilization.

PubMed

Schmeling, Max; Sartori, Neimar; Monteiro, Sylvio; Baratieri, Luiz

2014-01-01

This study evaluated the influence of 120 autoclave sterilization cycles on the color stability of two commercial shade guides (Vita Classical and Vita System 3D-Master). The specimens were evaluated by spectrophotometer before and after the sterilization cycles. The color was described using the three-dimensional CIELab system. The statistical analysis was performed in three chromaticity coordinates, before and after sterilization cycles, using the paired samples t test. All specimens became darker after autoclave sterilization cycles. However, specimens of Vita Classical became redder, while those of the Vita System 3D-Master became more yellow. Repeated cycles of autoclave sterilization caused statistically significant changes in the color coordinates of the two shade guides. However, these differences are considered clinically acceptable.

Coloring attributes of betalains: a key emphasis on stability and future applications.

PubMed

Martins, Natália; Roriz, Custódio Lobo; Morales, Patricia; Barros, Lillian; Ferreira, Isabel C F R

2017-04-19

Organoleptic characteristics largely determine food acceptance, selection, and subsequent consumption. Therefore, food colorants are extremely important in the food industry. However, based on the latest findings related to the side effects and toxicity issues of some synthetic colorants, consumers worldwide have shown increasing interest in natural alternatives. Betalains are good examples of natural colorants and therefore the present study reviews the main sources of these pigments, their structural elucidation and biosynthetic pathways, their chemical instability to different environmental factors, as well as their potential uses at the industrial level and also for pharmaceutical and cosmetic purposes, due to their ability to act as functional ingredients and health enhancers/promoters. Betalain natural pigments represent a promising and safe alternative to synthetic dyes, but their chemical instability has limited their widespread use. Temperature, pH, water activity, oxygen, light, chelating agents, the presence of other compounds, pigment concentration, storage, and processing conditions are the most important factors affecting their stability. It is, therefore, very important to establish optimum processing conditions to maximize the stability of betalains and their extraction yields, focusing on their effective use as natural food colorants, functional ingredients and value-added food products.

Visual wetness perception based on image color statistics.

PubMed

Sawayama, Masataka; Adelson, Edward H; Nishida, Shin'ya

2017-05-01

Color vision provides humans and animals with the abilities to discriminate colors based on the wavelength composition of light and to determine the location and identity of objects of interest in cluttered scenes (e.g., ripe fruit among foliage). However, we argue that color vision can inform us about much more than color alone. Since a trichromatic image carries more information about the optical properties of a scene than a monochromatic image does, color can help us recognize complex material qualities. Here we show that human vision uses color statistics of an image for the perception of an ecologically important surface condition (i.e., wetness). Psychophysical experiments showed that overall enhancement of chromatic saturation, combined with a luminance tone change that increases the darkness and glossiness of the image, tended to make dry scenes look wetter. Theoretical analysis along with image analysis of real objects indicated that our image transformation, which we call the wetness enhancing transformation, is consistent with actual optical changes produced by surface wetting. Furthermore, we found that the wetness enhancing transformation operator was more effective for the images with many colors (large hue entropy) than for those with few colors (small hue entropy). The hue entropy may be used to separate surface wetness from other surface states having similar optical properties. While surface wetness and surface color might seem to be independent, there are higher order color statistics that can influence wetness judgments, in accord with the ecological statistics. The present findings indicate that the visual system uses color image statistics in an elegant way to help estimate the complex physical status of a scene.

Starch, inulin and maltodextrin as encapsulating agents affect the quality and stability of jussara pulp microparticles.

PubMed

Lacerda, Ellen Cristina Quirino; Calado, Verônica Maria de Araújo; Monteiro, Mariana; Finotelli, Priscilla Vanessa; Torres, Alexandre Guedes; Perrone, Daniel

2016-10-20

The influence of encapsulating carbohydrates (EC) with varying properties on the technological and functional properties of jussara pulp microparticles produced by spray drying were evaluated using experimental design. Microparticles produced with sodium octenyl succinate (OSA) starch at 0.5 core to EC ratio and with mixtures of inulin and maltodextrin at 1.0 and 2.0 core to EC ratio showed darker color, and higher anthocyanins contents and antioxidant activity. Seven microparticles showing high water solubility and desirable surface morphology. Hygroscopicity (10.7% and 11.5%) and wettability (41s and 43s) were improved when OSA starch and mixtures of inulin and maltodextrin were used. The anthocyanins contents and color of the microparticles did not change when exposed to light at 50°C for 38days. Finally, microparticles produced at 1.0 core to EC ratio with 2/3 OSA starch, 1/6 inulin and 1/6 maltodextrin were selected. These microparticles may be applied as colorant in numerous foods, whilst adding prebiotic fiber and anthocyanins. Copyright © 2016 Elsevier Ltd. All rights reserved.

A feedback control strategy for the airfoil system under non-Gaussian colored noise excitation.

PubMed

Huang, Yong; Tao, Gang

2014-09-01

The stability of a binary airfoil with feedback control under stochastic disturbances, a non-Gaussian colored noise, is studied in this paper. First, based on some approximated theories and methods the non-Gaussian colored noise is simplified to an Ornstein-Uhlenbeck process. Furthermore, via the stochastic averaging method and the logarithmic polar transformation, one dimensional diffusion process can be obtained. At last by applying the boundary conditions, the largest Lyapunov exponent which can determine the almost-sure stability of the system and the effective region of control parameters is calculated.

A feedback control strategy for the airfoil system under non-Gaussian colored noise excitation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Yong, E-mail: hy@njust.edu.cn, E-mail: taogang@njust.edu.cn; Tao, Gang, E-mail: hy@njust.edu.cn, E-mail: taogang@njust.edu.cn

2014-09-01

The stability of a binary airfoil with feedback control under stochastic disturbances, a non-Gaussian colored noise, is studied in this paper. First, based on some approximated theories and methods the non-Gaussian colored noise is simplified to an Ornstein-Uhlenbeck process. Furthermore, via the stochastic averaging method and the logarithmic polar transformation, one dimensional diffusion process can be obtained. At last by applying the boundary conditions, the largest Lyapunov exponent which can determine the almost-sure stability of the system and the effective region of control parameters is calculated.

Optimization of composite coagulant made from polyferric chloride and tapioca starch in landfill leachate treatment

NASA Astrophysics Data System (ADS)

Shaylinda, M. Z. N.; Hamidi, A. A.; Mohd, N. A.; Ariffin, A.; Irvan, D.; Hazreek, Z. A. M.; Nizam, Z. M.

2018-04-01

In this research, the performance of polyferric chloride and tapioca flour as composite coagulants for partially stabilized leachate was investigated. Response surface methodology (RSM) was used to optimize the coagulation and flocculation process of partially stabilized leachate. Central composite design a standard design tool in RSM was applied to evaluate the interactions and effects of dose and pH. Dose 0.2 g/L Fe and pH 4.71 were the optimum value suggested by RSM. Experimental test based on the optimum condition, resulted in 95.9%, 94.6% and 50.4% of SS, color and COD removals, respectively. The percentage difference recorded between experimental and model responses was <5%. Therefore, it can be concluded that RSM was an appropriate optimization tool for coagulation and flocculation process.

Influence of surface layer removal of shade guide tabs on the measured color by spectrophotometer and spectroradiometer.

PubMed

Kim, Jin-Cheol; Yu, Bin; Lee, Yong-Keun

2008-12-01

To determine the changes in color parameters of Vitapan 3D-Master shade guide tabs by a spectrophotometer (SP) or a spectroradiometer (SR), and by the removal of the surface layer of the tabs that was performed to make a flat measuring surface for the SP color measurement. Color of the shade tabs was measured before and after removing the surface layer of the tabs using SP and SR. Correlations between the color parameters between the original (OR) and the surface layer removed (RM) tabs and between the SP and the SR measurements were determined (alpha=0.05). Based on SP, the lightness, chroma, CIE a* and b* values measured after the surface layer removal were higher than those of the original tabs except a few cases. Based on SR, the chroma and CIE a* and b* values measured after surface layer removal were higher than those of the original tabs except a few cases; however, in case of the lightness, the changes varied by the shade designation. Type of instrument influenced the changes in color parameters based on paired t-test (p<0.05). The color parameters of the OR and RM tabs showed correlations based on both SP and SR measurements (r=0.952-0.997 and p<0.01); however, color difference between the SP-RM and SR-OR tabs was in the range of 18.1-27.0 DeltaE(ab)(*) units (mean: 23.3+/-2.2). When the color of tooth-shaped objects is measured with a spectrophotometer or a spectroradiometer, measurement protocols should be specified because color difference by the surface layer removal and the instrument was high.

Optical and color stabilities of paint-on resins for shade modification of restorative resins.

PubMed

Arikawa, Hiroyuki; Kanie, Takahito; Fujii, Koichi; Ban, Seiji; Homma, Tetsuya; Takahashi, Hideo

2004-06-01

The purpose of this study was to examine the optical and color stabilities of the paint-on resin used for shade modification of restorative resins. Three shades of paint-on resin and two crown and bridge resins were used. The light transmittance characteristics of the materials during accelerated aging tests such as water immersion, toothbrush abrasion, ultraviolet (UV) light irradiation, and staining tests were measured. Discolorations of materials resulting from tests were also determined. There were no significant effects of water immersion, toothbrush abrasion and UV light irradiation on the light transmittance and visible color change of paint-on resins, whereas the staining tests significantly decreased the light transmittance and increased color change of the translucent shades of materials. Our results indicate that the paint-on resins exhibit stable optical properties and color appearance, which are at least as good as the crown and bridge resins.

Plasmonic coloring of noble metals rendered by picosecond laser exposure

NASA Astrophysics Data System (ADS)

Guay, J.-M.; CalaLesina, A.; Gordon, P. G.; Baxter, J.; Barry, S. T.; Ramunno, L.; Berini, P.; Weck, A.

2017-02-01

We show the angle-independent coloring of metals in air arising from nanoparticle distributions on metal surfaces created via picosecond laser processing. Each of the colors is linked to a unique total accumulated fluence, rendering the process compatible with industry. We report the coating of the colored metal surfaces using atomic layer deposition which is shown to preserve colors and provide mechanical and chemical protection Laser bursts are composed of closely time-spaced pulses separated by 12.8 ns. The coloring of silver using burst versus non-burst is shown to increase the Chroma, or color saturation, by 50% and broaden the color Lightness range by up to 60%. The increase in Chroma and Lightness are accompanied by the creation of 3 kinds of different laser-induced periodic surface structures (LIPSS). One of these structures is measured to be 10 times the wavelength of light and are not yet explained by conventional theories. Two temperature model simulations of laser bursts interacting with the metal surface show a significant increase in the electron-phonon coupling responsible for the well-defined LIPSS observed on the surface of silver. Finite-difference time-domain simulations of nanoparticles distributed on the high-spatial frequency LIPSS (HSFL) explain the increase in color saturation (i.e. Chroma of the colors) by the enhanced absorption and enriched plasmon resonances.

Facile formation of biomimetic color-tuned superhydrophobic magnesium alloy with corrosion resistance.

PubMed

Ishizaki, Takahiro; Sakamoto, Michiru

2011-03-15

The design of color-tuned magnesium alloy with anticorrosive properties and damping capacity was created by means of a simple and inexpensive method. The vertically self-aligned nano- and microsheets were formed on magnesium alloy AZ31 by a chemical-free immersion process in ultrapure water at a temperature of 120 °C, resulting in the color expression. The color changed from silver with metallic luster to some specific colors such as orange, green, and orchid, depending on the immersion time. The color-tuned magnesium alloy showed anticorrosive performance and damping capacity. In addition, the colored surface with minute surface textures was modified with n-octadecyltrimethoxysilane (ODS), leading to the formation of color-tuned superhydrophobic surfaces. The corrosion resistance of the color-tuned superhydrophobic magnesium alloy was also investigated using electrochemical potentiodynamic measurements. Moreover, the color-tuned superhydrophobic magnesium alloy showed high hydrophobicity not just for pure water but also for corrosive liquids, such as acidic, basic, and some aqueous salt solutions. In addition, the American Society for Testing and Materials (ASTM) standard D 3359-02 cross cut tape test was performed to investigate the adhesion of the color-tuned superhydrophobic film to the magnesium alloy surface.

TiO2-Nanofillers Effects on Some Properties of Highly- Impact Resin Using Different Processing Techniques.

PubMed

Aziz, Hawraa Khalid

2018-01-01

The criteria of conventional curing of polymethyl methacrylate do not match the standard properties of the denture base materials. This research was conducted to investigate the addition of TiO 2 nano practical on impact strength, thermal conductivity and color stability of acrylic resin cured by microwave in comparison to the conventional cured of heat-polymerized acrylic resin. 120 specimens made of high impact acrylic resin were divided into two main groups according to the type of curing (water bath, microwave), then each group was subdivided into two groups according to the addition of 3% TiO 2 nano-fillers and control group (without the addition of TiO 2 0%). Each group was subdivided according to the type of test into 3 groups with 10 specimens for each group. Data were statistically analyzed using Student t-test to detect the significant differences between tested and control groups at significance level ( P <0.05). According to curing type methods, the results showed that there was a significant decrease in impact strength of microwaved cured resin, but there was no significant difference in the thermal conductivity and color stability of resin. In addition, by using nanofiller, there was a significant increase in the impact strength and color stability with the addition of 3% TiO 2 nanofillers, but no significant difference was found in the thermal conductivity of the acrylic resin. The microwave curing of acrylic resin had no change in the color stability and thermal conductivity in comparison to the water bath, but the impact strength was decreased. The addition of 3% TiO 2 improved the impact and the color stability, but the thermal conductivity did not change.

Pluto and Charon: Surface Colors and Compositions - A Hypothesis

NASA Technical Reports Server (NTRS)

Cruikshank, D. P.

2016-01-01

The surface of Pluto displays an array of colors ranging from yellow to red to brown, while the surface of Charon is largely gray with a north polar zone of red color similar to regions on Pluto. Pluto's surface shows layers of intensely colored material in tilted and transported blocks, and fractured geo-graphical units. This arrangement suggests episodes of formation or deposition of that material interspersed with episodes of emplacement of ices having little or no color. The ices identified on the surfaces of these two bodies (N2, CH4, CO, C2H6, H2O on Pluto, and H2O and NH3 on Charon) are colorless, as are nearly all ices in a powdery state. The colors on Pluto probably arise from the in situ formation of a macro-molecular carbonaceous material generated by energetic processing of the ices on the surface. Laboratory experiments producing refractory tholins particularly relevant to Pluto explored the chemistry of both UV and low-energy electron bombardment of a mix of Pluto ices (N2:CH4:CO = 100:1:1). We can term this Pluto ice tholin PIT. Water ice in the crystalline state characterizes Charon's surface, and while most of Charon's surface is neutral in color, with geometric albedo approximately 0.38, the polar zone and a light cover of fainter but similar reddish color over some surface regions suggest a common origin with the colored material on Pluto. NH3 or NH3 x nH2O was identified from disk-integrated Earth-based spectra, and a few concentrated NH3 exposures have been found in the New Horizons spectral images.

Effect of Surface-Modified TiO2 Nanoparticles on the Anti-Ultraviolet Aging Performance of Foamed Wheat Straw Fiber/Polypropylene Composites

PubMed Central

Xuan, Lihui; Han, Guangping; Wang, Dong; Cheng, Wanli; Gao, Xun; Chen, Feng; Li, Qingde

2017-01-01

Surface modification and characterization of titanium dioxide (TiO2) nanoparticles and their roles in thermal, mechanical, and accelerated aging behavior of foamed wheat straw fiber/polypropylene (PP) composites are investigated. To improve the dispersion of nanoparticles and increase the possible interactions between wheat straw fiber and the PP matrix, the surface of the TiO2 nanoparticles was modified with ethenyltrimethoxy silane (A171), a silane coupling agent. The grafting of A171 on the TiO2 nanoparticles’ surface was characterized by Fourier transform infrared spectroscopy (FTIR). The wheat straw fibers treated with A171 and modified TiO2 nanoparticles were characterized by FTIR and thermogravimetric analysis (TGA). FTIR spectra confirmed that the organic functional groups of A171 were successfully grafted onto the TiO2 nanoparticles and wheat straw fibers, and the modified TiO2 nanoparticles were adsorbed onto the wheat straw fibers. Thermogravimetric analysis showed that a higher thermal stability of the wheat straw fiber was obtained with the modified TiO2 nanoparticles. The flexural, tensile, and impact properties were improved. A higher ultraviolet (UV) stability of the samples treated with modified TiO2 nanoparticles was exhibited by the study of the color change and loss in mechanical properties. PMID:28772816

Lightness Constancy in Surface Visualization

PubMed Central

Szafir, Danielle Albers; Sarikaya, Alper; Gleicher, Michael

2016-01-01

Color is a common channel for displaying data in surface visualization, but is affected by the shadows and shading used to convey surface depth and shape. Understanding encoded data in the context of surface structure is critical for effective analysis in a variety of domains, such as in molecular biology. In the physical world, lightness constancy allows people to accurately perceive shadowed colors; however, its effectiveness in complex synthetic environments such as surface visualizations is not well understood. We report a series of crowdsourced and laboratory studies that confirm the existence of lightness constancy effects for molecular surface visualizations using ambient occlusion. We provide empirical evidence of how common visualization design decisions can impact viewers’ abilities to accurately identify encoded surface colors. These findings suggest that lightness constancy aids in understanding color encodings in surface visualization and reveal a correlation between visualization techniques that improve color interpretation in shadow and those that enhance perceptions of surface depth. These results collectively suggest that understanding constancy in practice can inform effective visualization design. PMID:26584495

Color stability and flexural strength of poly (methyl methacrylate) and bis-acrylic composite based provisional crown and bridge auto-polymerizing resins exposed to beverages and food dye: an in vitro study.

PubMed

Gujjari, Anil K; Bhatnagar, Vishrut M; Basavaraju, Ravi M

2013-01-01

To evaluate the color stability and flexural strength of poly (methyl methacrylate) (PMMA) and bis-acrylic composite based provisional crown and bridge auto-polymerizing resins exposed to tea, coffee, cola, and food dye. Two provisional crown and bridge resins, one DPI self-cure tooth molding powder (PMMA) (Group A), and one Protemp 4 Temporization Material (bis-acrylic composite) (Group B) were used. Disk-shaped specimens for color stability testing (n = 30 for each material) and bar-shaped specimens for flexural strength testing (n = 30 for each material) were fabricated using a metal mold. The specimens were immersed in artificial saliva, artificial saliva + tea, artificial saliva + coffee, artificial saliva + cola, and artificial saliva + food dye solutions and stored in an incubator at 37°C. Color measurements were taken before immersion, and then after 3 and 7 days of immersion. Flexural strength was evaluated after 7 days of immersion. Group A showed significantly higher color stability as compared to Group B, and artificial saliva + coffee solution had the most staining capacity for the resins. Test solutions had no effect on the flexural strength of Group A, but Group B specimens immersed in artificial saliva + cola showed significantly lower flexural strength values as compared to the control group. The findings of the study showed that for materials used in the study, PMMA was more color stable than bis-acrylic composite based resin. Also, material based on PMMA was more resistant to damage from dietary beverages as compared to bis-acrylic composite based provisional crown and bridge resin.

Selection of a chitosan gelatin-based edible coating for color preservation of beef in retail display.

PubMed

Cardoso, Giselle Pereira; Dutra, Monalisa Pereira; Fontes, Paulo Rogério; Ramos, Alcinéia de Lemos Souza; Gomide, Lúcio Alberto de Miranda; Ramos, Eduardo Mendes

2016-04-01

Chitosan gelatin-based coating films were applied to beef steaks, and their effects on color preservation and lipid oxidation during retail display were evaluated. Response surface methodology was used to model and describe the effects of different biopolymer concentrations (0 to 6% gelatin; 0.5 to 1.5% chitosan; and 0 to 12% glycerol based on dry gelatin+chitosan weight) in the coating film for optimizing the best combination for meat application. Film application reduced weight loss and lipid oxidation of the steaks after 5 days of storage, and films with higher gelatin concentrations were more effective. The percentage levels of different myoglobin-redox forms were not affected by coating, but myoglobin oxidation during retail display was reduced and the percentage of deoxymyoglobin increased with the gelatin content of the film. Steak color stability during retail display was promoted by film application; the steaks exhibited a darker, more intensely red color when coated in blends with higher gelatin and chitosan contents. Blends containing between 3% and 6% gelatin, between 0.5% and 1.0% chitosan and 6% glycerol exhibited the best results and provide a promising alternative to the preservation of beef in retail display. Copyright © 2015 Elsevier Ltd. All rights reserved.

The effect of repeated firings on the color change and surface roughness of dental ceramics

PubMed Central

Yılmaz, Kerem; Ozturk, Caner

2014-01-01

PURPOSE The color of the ceramic restorations is affected by various factors such as brand, thickness of the layered the ceramic, condensation techniques, smoothness of surface, number of firings, firing temperature and thickness of dentin. The aim of this study was to evaluate the color change and surface roughness in dental porcelain with different thicknesses during repeated firings. MATERIALS AND METHODS Disc-shaped (N=21) metal-ceramic samples (IPS Classic; Ivoclar Vivadent; Shaar, Liechtenstein) with different thickness were exposed to repeated firings. Color measurement of the samples was made using a colorimeter and profilometer was used to determine surface roughness. ANOVA and Tukey tests with repeated measurements were used for statistical analysis. RESULTS The total thickness of the ceramics which is less than 2 mm significantly have detrimental effect on the surface properties and color of porcelains during firings (P<.05). CONCLUSION Repeated firings have effects on the color change and surface roughness of the dental ceramics and should be avoided. PMID:25177475

Red pepper (Capsicum annuum) carotenoids as a source of natural food colors: analysis and stability-a review.

PubMed

Arimboor, Ranjith; Natarajan, Ramesh Babu; Menon, K Ramakrishna; Chandrasekhar, Lekshmi P; Moorkoth, Vidya

2015-03-01

Carotenoids are increasingly drawing the attention of researchers as a major natural food color due to their inherent nutritional characteristics and the implicated possible role in prevention and protection against degenerative diseases. In this report, we review the role of red pepper as a source for natural carotenoids. The composition of the carotenoids in red pepper and the application of different methodologies for their analysis were discussed in this report. The stability of red pepper carotenoids during post-harvest processing and storage is also reviewed. This review highlights the potential of red pepper carotenoids as a source of natural food colors and also discusses the need for a standardized approach for the analysis and reporting of composition of carotenoids in plant products and designing model systems for stability studies.

The Representation of Color across the Human Visual Cortex: Distinguishing Chromatic Signals Contributing to Object Form Versus Surface Color.

PubMed

Seymour, K J; Williams, M A; Rich, A N

2016-05-01

Many theories of visual object perception assume the visual system initially extracts borders between objects and their background and then "fills in" color to the resulting object surfaces. We investigated the transformation of chromatic signals across the human ventral visual stream, with particular interest in distinguishing representations of object surface color from representations of chromatic signals reflecting the retinal input. We used fMRI to measure brain activity while participants viewed figure-ground stimuli that differed either in the position or in the color contrast polarity of the foreground object (the figure). Multivariate pattern analysis revealed that classifiers were able to decode information about which color was presented at a particular retinal location from early visual areas, whereas regions further along the ventral stream exhibited biases for representing color as part of an object's surface, irrespective of its position on the retina. Additional analyses showed that although activity in V2 contained strong chromatic contrast information to support the early parsing of objects within a visual scene, activity in this area also signaled information about object surface color. These findings are consistent with the view that mechanisms underlying scene segmentation and the binding of color to object surfaces converge in V2. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

Effect of repeated immersion solution cycles on the color stability of denture tooth acrylic resins

PubMed Central

da SILVA, Paulo Maurício Batista; ACOSTA, Emílio José Tabaré Rodríguez; JACOBINA, Matheus; PINTO, Luciana de Rezende; PORTO, Vinícius Carvalho

2011-01-01

Objective Chemical solutions have been widely used for disinfection of dentures, but their effect on color stability of denture tooth acrylic resins after repeated procedures is still unclear. The aim of this in vitro study was to evaluate whether repeated cycles of chemical disinfectants affected the color stability of two denture tooth acrylic resins. Material and Methods Sixty disc-shaped specimens (40 mm x 3 mm) were fabricated from two different brands (Artiplus and Trilux) of denture tooth acrylic resin. The specimens from each brand (n=30) were randomly divided into 6 groups (n=5) and immersed in the following solutions: distilled water (control group) and 5 disinfecting solutions (1% sodium hypochlorite, 2% sodium hypochlorite, 5.25% sodium hypochlorite, 2% glutaraldehyde, and 4% chlorhexidine gluconate). Tooth color measurements were made by spectrophotometry. Before disinfection, the initial color of each tooth was recorded. Further color measurements were determined after subjecting the specimens to 7, 21, 30, 45, 60, and 90 immersion cycles in each tested solution. Color differences (ΔE*) were determined using the CIE L*a*b* color system. Data were analyzed using two-way repeated measures analysis of variance (ANOVA) followed by Tukey tests. The significance level was set at 5%. Results There were statistically significant differences in ΔE* among the 5 disinfectants and water during the 90 cycles of immersion for both denture tooth acrylic resins. Distilled water promoted the greatest color change in both denture tooth acrylic resins, nevertheless none of tested disinfectants promoted ΔE* values higher than 1.0 on these acrylic materials during the 90 cycles of disinfection. Conclusions Repeated immersion cycles in disinfecting solutions alter ∆E* values, however these values do not compromise the color of the tested denture tooth acrylic resins because they are imperceptible to the human eye. PMID:22230997

Europa Stunning Surface

NASA Image and Video Library

2014-11-21

The puzzling, fascinating surface of Jupiter icy moon Europa looms large in this newly-reprocessed [sic] color view, made from images taken by NASA Galileo spacecraft in the late 1990s. This is the color view of Europa from Galileo that shows the largest portion of the moon's surface at the highest resolution. The view was previously released as a mosaic with lower resolution and strongly enhanced color (see PIA02590). To create this new version, the images were assembled into a realistic color view of the surface that approximates how Europa would appear to the human eye. The scene shows the stunning diversity of Europa's surface geology. Long, linear cracks and ridges crisscross the surface, interrupted by regions of disrupted terrain where the surface ice crust has been broken up and re-frozen into new patterns. Color variations across the surface are associated with differences in geologic feature type and location. For example, areas that appear blue or white contain relatively pure water ice, while reddish and brownish areas include non-ice components in higher concentrations. The polar regions, visible at the left and right of this view, are noticeably bluer than the more equatorial latitudes, which look more white. This color variation is thought to be due to differences in ice grain size in the two locations. Images taken through near-infrared, green and violet filters have been combined to produce this view. The images have been corrected for light scattered outside of the image, to provide a color correction that is calibrated by wavelength. Gaps in the images have been filled with simulated color based on the color of nearby surface areas with similar terrain types. This global color view consists of images acquired by the Galileo Solid-State Imaging (SSI) experiment on the spacecraft's first and fourteenth orbits through the Jupiter system, in 1995 and 1998, respectively. Image scale is 1 mile (1.6 kilometers) per pixel. North on Europa is at right. http://photojournal.jpl.nasa.gov/catalog/PIA19048

Shear-Sensitive Liquid Crystal Coating Method Applied Through Transparent Test Surfaces

NASA Technical Reports Server (NTRS)

Reda, Daniel C.; Wilder, Michael C.

1999-01-01

Research conducted at NASA Ames Research Center has shown that the color-change response of a shear-sensitive liquid crystal coating (SSLCC) to aerodynamic shear depends on both the magnitude of the local shear vector and its direction relative to the observer's in-plane line of sight. In conventional applications, the surface of the SSLCC exposed to aerodynamic shear is illuminated with white light from the normal direction and observed from an oblique above-plane view angle of order 30 deg. In this top-light/top-view mode, shear vectors with components directed away from the observer cause the SSLCC to exhibit color-change responses. At any surface point, the maximum color change (measured from the no-shear red or orange color) always occurs when the local vector is aligned with, and directed away from, the observer. The magnitude of the color change at this vector-observer-aligned orientation scales directly with shear stress magnitude. Conversely, any surface point exposed to a shear vector with a component directed toward the observer exhibits a non-color-change response, always characterized by a rusty-red or brown color, independent of both shear magnitude and direction. These unique, highly directional color-change responses of SSLCCs to aerodynamic shear allow for the full-surface visualization and measurement of continuous shear stress vector distributions. The objective of the present research was to investigate application of the SSLCC method through a transparent test surface. In this new back-light/back-view mode, the exposed surface of the SSLCC would be subjected to aerodynamic shear stress while the contact surface between the SSLCC and the solid, transparent wall would be illuminated and viewed in the same geometrical arrangement as applied in conventional applications. It was unknown at the outset whether or not color-change responses would be observable from the contact surface of the SSLCC, and, if seen, how these color-change responses might relate to those observed in standard practice.

Effect of the atmosphere on the color coordinates of sunlit surfaces

NASA Astrophysics Data System (ADS)

Willers, Cornelius J.; Viljoen, Johan W.

2016-02-01

Aerosol attenuation in the atmosphere has a relatively weak spectral variation compared to molecular absorption. However, the solar spectral irradiance differs considerably for the sun at high zenith angles versus the sun at low zenith angles. The perceived color of a sunlit object depends on the object's spectral reflectivity as well as the irradiance spectrum. The color coordinates of the sunlit object, hence also the color balance in a scene, shift with changes in the solar zenith angle. The work reported here does not claim accurate color measurement. With proper calibration mobile phones may provide reasonably accurate color measurement, but the mobile phones used for taking these pictures and videos are not scientific instruments and were not calibrated. The focus here is on the relative shift of the observed colors, rather than absolute color. The work in this paper entails the theoretical analysis of color coordinates of surfaces and how they change for different colored surfaces. Then follows three separate investigations: (1) Analysis of a number of detailed atmospheric radiative transfer code (Modtran) runs to show from the theory how color coordinates should change. (2) Analysis of a still image showing how the colors of two sample surfaces vary between sunlit and shaded areas. (3) Time lapse video recordings showing how the color coordinates of a few surfaces change as a function of time of day. Both the theoretical and experimental work shows distinct shifts in color as function of atmospheric conditions. The Modtran simulations demonstrate the effect from clear atmospheric conditions (no aerosol) to low visibility conditions (5 km visibility). Even under moderate atmospheric conditions the effect was surprisingly large. The experimental work indicated significant shifts during the diurnal cycle.

Effect of different solutions on color stability of acrylic resin-based dentures.

PubMed

Goiato, Marcelo Coelho; Nóbrega, Adhara Smith; dos Santos, Daniela Micheline; Andreotti, Agda Marobo; Moreno, Amália

2014-01-01

The aim of this study was to evaluate the effect of thermocycling and immersion in mouthwash or beverage solutions on the color stability of four different acrylic resin-based dentures (Onda Cryl, OC; QC20, QC; Classico, CL; and Lucitone, LU). The factors evaluated were type of acrylic resin, immersion time, and solution (mouthwash or beverage). A total of 224 denture samples were fabricated. For each type of resin, eight samples were immersed in mouthwashes (Plax-Colgate, PC; Listerine, LI; and Oral-B, OB), beverages (coffee, CP; cola, C; and wine, W), and artificial saliva (AS; control). The color change (DE) was evaluated before (baseline) and after thermocycling (T1), and after immersion in solution for 1 h (T2), 3 h (T3), 24 h (T4), 48 h (T5), and 96 h (T6). The CIE Lab system was used to determine the color changes. The thermocycling test was performed for 5000 cycles. Data were submitted to three-way repeated-measures analysis of variance and Tukey's test (p<0.05). When the samples were immersed in each mouthwash, all assessed factors, associated or not, significantly influenced the color change values, except there was no association between the mouthwash and acrylic resin. Similarly, when the samples were immersed in each beverage, all studied factors influenced the color change values. In general, regardless of the solution, LU exhibited the greatest DE values in the period from T1 to T5; and QC presented the greatest DE values at T6. Thus, thermocycling and immersion in the various solutions influenced the color stability of acrylic resins and QC showed the greatest color alteration.

Colour Model for Outdoor Machine Vision for Tropical Regions and its Comparison with the CIE Model

NASA Astrophysics Data System (ADS)

Sahragard, Nasrolah; Ramli, Abdul Rahman B.; Hamiruce Marhaban, Mohammad; Mansor, Shattri B.

2011-02-01

Accurate modeling of daylight and surface reflectance are very useful for most outdoor machine vision applications specifically those which are based on color recognition. Existing daylight CIE model has drawbacks that limit its ability to predict the color of incident light. These limitations include lack of considering ambient light, effects of light reflected off the ground, and context specific information. Previously developed color model is only tested for a few geographical places in North America and its accountability is under question for other places in the world. Besides, existing surface reflectance models are not easily applied to outdoor images. A reflectance model with combined diffuse and specular reflection in normalized HSV color space could be used to predict color. In this paper, a new daylight color model showing the color of daylight for a broad range of sky conditions is developed which will suit weather conditions of tropical places such as Malaysia. A comparison of this daylight color model and daylight CIE model will be discussed. The colors of matte and specular surfaces have been estimated by use of the developed color model and surface reflection function in this paper. The results are shown to be highly reliable.

Effects of oxidation potential and retention time on electrochromic stability of poly (3-hexyl thiophene) films

NASA Astrophysics Data System (ADS)

Kim, Tae-Ho; Hyun Song, Seok; Kim, Hyo-Jae; Oh, Seong-Hyeon; Han, Song-Yi; Kim, Goung; Nah, Yoon-Chae

2018-06-01

Herein, we report the effects of applied voltage on the electrochromic (EC) stability of poly(3-hexylthiophene) (P3HT) films during EC reactions. The transmittance difference and cycling stability of these films were monitored to optimize the oxidation voltage, and their chemical compositions were analyzed by X-ray photoelectron spectroscopy after long-term electrochemical cycling. High oxidation voltages increased the color contrast of P3HT films but decreased their cycling stability due to facilitating chemical degradation. Furthermore, at an optimized oxidation voltage, the retention time during potential pulsing was adjusted utilizing the optical memory of P3HT, revealing that the decreased voltage application time reduced power consumption by 9.6% and enhanced EC stability without loss of color contrast.

Design of the scanning mode coated glass color difference online detection system

NASA Astrophysics Data System (ADS)

Bi, Weihong; Zhang, Yu; Wang, Dajiang; Zhang, Baojun; Fu, Guangwei

2008-03-01

A design of scanning mode coated glass color difference online detection system was introduced. The system consisted of color difference data acquirement part and orbit control part. The function of the color difference data acquirement part was to acquire glass spectral reflectance and then processed them to get the color difference value. Using fiber for light guiding, the reflected light from surface of glass was transmitted into light division part, and the dispersive light was imaged on linear CCD, and then the output signals from the CCD was sampled pixel by pixel, and the spectral reflectance of coated glass was obtained finally. Then, the acquired spectral reflectance signals was sent to industrial personal computer through USB interface, using standard color space and color difference formula nominated by International Commission on Illumination (CIE) in 1976 to process these signals, and the reflected color parameter and color difference of coated glass was gained in the end. The function of the orbit control part was to move the detection probe by way of transverse scanning mode above the glass strip, and control the measuring start-stop time of the color difference data acquirement part at the same time. The color difference data acquirement part of the system was put on the orbit which is after annealing area in coated glass production line, and the protected fiber probe was placed on slide of the orbit. Using single chip microcomputer to control transmission mechanism of the slide, which made the slide move by way of transverse scanning mode on the glass strip, meanwhile, the color difference data acquirement part of the system was also controlled by the single chip microcomputer, and it made the acquirement part measure color difference data when the probe reached the needed working speed and required place on the glass strip. The scanning mode coated glass color difference online detection system can measure color parameter and color difference of each transverse point on glass strip, it can also measure lengthways color stability on glass strip. Furthermore, the measuring results can be transmitted to coated control room through intranet, so it is very useful to improve producing technique in time. In addition, equipping necessary marking machine, this system can classify glass board automatically based on the measuring result.

Role of color memory in successive color constancy.

PubMed

Ling, Yazhu; Hurlbert, Anya

2008-06-01

We investigate color constancy for real 2D paper samples using a successive matching paradigm in which the observer memorizes a reference surface color under neutral illumination and after a temporal interval selects a matching test surface under the same or different illumination. We find significant effects of the illumination, reference surface, and their interaction on the matching error. We characterize the matching error in the absence of illumination change as the "pure color memory shift" and introduce a new index for successive color constancy that compares this shift against the matching error under changing illumination. The index also incorporates the vector direction of the matching errors in chromaticity space, unlike the traditional constancy index. With this index, we find that color constancy is nearly perfect.

Effect of packaging atmospheres on storage quality characteristics of heavily marbled beef longissimus steaks.

PubMed

Yang, Xiaoyin; Zhang, Yimin; Zhu, Lixian; Han, Mingshan; Gao, Shujuan; Luo, Xin

2016-07-01

The objective of this study was to investigate the effects of modified atmosphere packaging (MAP) systems on shelf-life and quality of beef steaks with high marbling. Four packaging types were used including 80% O2 MAP (80% O2+20% CO2), 50% O2 MAP (50% O2+30% CO2+20% N2), carbon monoxide MAP (0.4% CO+30% CO2+69.6% N2) and vacuum packaging (VP). Steaks were displayed under simulated retail conditions at 4°C for 12days. Purge loss, pH, color stability, oxidative stability and microbial counts were monitored. Aerobically packaged steaks exhibited a bright-red color at the first 4days. However, discoloration and oxidation became major factors limiting their shelf-life to 8days. Compared with aerobic packaging, anaerobic packaging extended shelf-life of heavily marbled beef steaks, due to better color stability, together with lower oxidation and microbial populations. Among all packaging methods, CO-MAP had the best preservation for steaks, with more red color than other packaging types. Copyright © 2016 Elsevier Ltd. All rights reserved.

PLUTO AND CHARON WITH THE HUBBLE SPACE TELESCOPE. II. RESOLVING CHANGES ON PLUTO'S SURFACE AND A MAP FOR CHARON

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buie, Marc W.; Young, Eliot F.; Young, Leslie A.

We present new imaging of the surface of Pluto and Charon obtained during 2002-2003 with the Hubble Space Telescope (HST) Advanced Camera for Surveys (ACS) instrument. Using these data, we construct two-color albedo maps for the surfaces of both Pluto and Charon. Similar mapping techniques are used to re-process HST/Faint Object Camera (FOC) images taken in 1994. The FOC data provide information in the ultraviolet and blue wavelengths that show a marked trend of UV-bright material toward the sunlit pole. The ACS data are taken at two optical wavelengths and show widespread albedo and color variegation on the surface ofmore » Pluto and hint at a latitudinal albedo trend on Charon. The ACS data also provide evidence for a decreasing albedo for Pluto at blue (435 nm) wavelengths, while the green (555 nm) data are consistent with a static surface over the one-year period of data collection. We use the two maps to synthesize a true visual color map of Pluto's surface and investigate trends in color. The mid- to high-latitude region on the sunlit pole is, on average, more neutral in color and generally higher albedo than the rest of the surface. Brighter surfaces also tend to be more neutral in color and show minimal color variations. The darker regions show considerable color diversity arguing that there must be a range of compositional units in the dark regions. Color variations are weak when sorted by longitude. These data are also used to constrain astrometric corrections that enable more accurate orbit fitting, both for the heliocentric orbit of the barycenter and the orbit of Pluto and Charon about their barycenter.« less

Streaks Of Colored Water Indicate Surface Airflows

NASA Technical Reports Server (NTRS)

Wilcox, Floyd J., Jr.

1994-01-01

Response faster and contamination less than in oil-flow technique. Flowing colored water provides accurate and clean way to reveal flows of air on surfaces of models in wind tunnels. Colored water flows from small orifices in model, forming streak lines under influence of air streaming over surface of model.

Control of rotting and browning of Longan fruit cv. Biew Kiew after harvested by sulphur dioxide treatment under various storage temperatures.

PubMed

Chitbanchong, W; Sardsud, V; Whangchai, K; Koslanund, R; Thobunluepop, P

2009-11-15

The experiment of Longan fruit cv. Biew Kiew, untreated (control) and treated with SO2 treatment were stored under 2 +/- 2 and 7 +/- 2 degrees C for 0, 2, 4, 6 and 8 weeks were studied. The treatment of fresh longan fruit with SO2 fumigation combined with the suitable storage condition improved the overall longan fruit quality, especially on inner and outer peel tissue and aril color than no SO2 treatment. Treatment stabilizes peel color with no subsequent loss of color during storage (fruit color were bright-yellowish color). When the fruit showed during SO2 treatment, increasing of storage duration and temperatures, the dark color of inner and outer peel of longan fruit was appeared, this was correlated with the increasing of PPO activity. The activity of PPO enzyme in control fruit (no SO2 treatment) gradually lower than SO2 treatments. Fruit exposed to cool storage temperature (2 degrees C) exhibited a lower PPO enzymatic activity compared to those kept in high storage temperature (7 degrees C). Moreover, PPO enzymatic activity significantly increased over the storage durations The additional SO2 treatment no subsequent loss of weight of longan fruit during storage. However, the sulphite residues could detect immediately after SO2 treatment in all part of longan fruit, especially on aril tissue. The SEM evaluation found that the surface cracking was also impair the physiological function of the cuticle and increasing water permeability, which may cause water soaking at the inner side of the peel. The injured cell would accelerate the oxidation of phenolic substances and the oxidative products resulted in dark color of inner and outer peel.

Environment and human friendly colored materials prepared using black and white components.

PubMed

Takeoka, Yukikazu

2018-05-10

Our lives in the present age are full of colorful items. However, when many coloring materials cannot be used due to environmental concerns, this colorful life that has been constructed will be diminished. Maintaining our rich lifestyle necessitates the development of technologies that can make safe and secure color materials from materials with less burden on people and the environment. Herein, the author reveals that structural colored materials with little angle dependence can be prepared using various materials with short-range order in the refractive index, which is comparable to the wavelength of visible light, and with the aid of a black substance. This approach enables the preparation of colorful materials from materials that have a low environmental burden and are non-toxic to living things; examples of such materials include silica, carbon black, and iron oxide. If we can achieve mechanical stabilization and hue stabilization of these coloring materials, we can develop new green pigments with low toxicity, good color development, and high durability. The use of conventional angular-dependent structural colored materials has been limited. However, structural colored materials with no angle dependence, such as those prepared by the author, can be used in fields where pigments have traditionally been used. For example, they could be used in coating materials for automobiles and buildings, and in pigments used by artists. Environmentally friendly green color materials are expected to promote sustainable development. In this review, I will describe how to prepare structural colored materials with less angle dependency using white and black substances previously reported by the author.

Color stability of maxillofacial silicone with nanoparticle pigment and opacifier submitted to disinfection and artificial aging.

PubMed

Filié Haddad, Marcela; Coelho Goiato, Marcelo; Micheline Dos Santos, Daniela; Moreno, Amália; Filipe D'almeida, Nuno; Alves Pesqueira, Aldiéris

2011-09-01

The purpose of this study was to evaluate the color stability of a maxillofacial elastomer with the addition of a nanoparticle pigment and∕or an opacifier submitted to chemical disinfection and artificial aging. Specimens were divided into four groups (n = 30): group I: silicone without pigment or opacifier, group II: ceramic powder pigment, group III: Barium sulfate (BaSO(4)) opacifier, and group IV: ceramic powder and BaSO(4) opacifier. Specimens of each group (n = 10) were disinfected with effervescent tablets, neutral soap, or 4% chlorhexidine gluconate. Disinfection was done three times a week during two months. Afterward, specimens were submitted to different periods of artificial aging. Color evaluation was initially done, after 60 days (disinfection period) and after 252, 504, and 1008 h of artificial aging with aid of a reflection spectrophotometer. Data were analyzed by three-way ANOVA and Tukey test (α = 0.05). The isolated factor disinfection did not statistically influence the values of color stability among groups. The association between pigment and BaSO(4) opacifier (GIV) was more stable in relationship to color change (△E). All values of △E obtained, independent of the disinfectant and the period of artificial aging, were considered acceptable in agreement with the norms presented in literature.

The characterization of electroplex generated from the interface between 2-(4-trifluoromethyl-2-hydroxyphenyl)benzothiazole] zinc and N,N'-diphenyl-N,N'- bis(1-naphthyl)-(1,1'-biphenyl)-4,4'-diamine

NASA Astrophysics Data System (ADS)

Zhang, Ye; Hao, Yuying; Meng, Weixin; Xu, Huixia; Wang, Hua; Xu, Bingshe

2012-03-01

The electroplex between (2-(4-trifluoromethyl-2-hydroxyphenyl)benzothiazole) zinc [Zn(4-TfmBTZ)2] as an electron-acceptor and N,N'-diphenyl-N,N'-bis(1-naphthyl)-(1,1'-biphenyl)-4,4'-diamine (NPB) as an electron-donor was characterized by bilayer, blend, and multilayer quantum-well (MQW) device, respectively. The blend composition and quantum-well number are effective parameters for tuning electroluminescence color. White light with high color purity and color rendering index (CRI) was observed from these devices based on Zn(4-TfmBTZ)2/NPB. Moreover, the blend and MQW devices all exhibit high operation stability, hence excellent color stability. For the device with 5 mol% NPB in blend layer, its Commission International Del'Eclairage (CIE) coordinate region is x=0.28-0.31, y=0.33-0.35 and CRI is 83.3-91.2 at 5-9 V. For MQW structure device with NPB of 60 nm thickness, its CIE coordinate region is x=0.29-0.32, y=0.31-0.34 and CRI=87.9-92.5 at 10-15 V. Such high color stability and purity and CRI, being close to ideal white light, are of current important for white OLED.

In Situ Crystallization Synthesis of CsPbBr3 Perovskite Quantum Dot-Embedded Glasses with Improved Stability for Solid-State Lighting and Random Upconverted Lasing.

PubMed

Yuan, Shuo; Chen, Daqin; Li, Xinyue; Zhong, Jiasong; Xu, Xuhui

2018-06-06

All-inorganic cesium lead bromide CsPbBr 3 perovskite quantum dots (QDs) are emerging as potential candidates for their applications in optoelectronic devices but they suffer from poor long-term stability due to their high sensitivity to UV irradiation, heat, and especially to moisture. Although great advances in improving stability of perovskite QDs have been achieved by surface modification or encapsulation in polymer and silica, they are not sufficiently refrained from external environment due to nondense structures of these protective layers. In this work, in situ nanocrystallization strategy is developed to directly grow CsPbBr 3 QDs among a specially designed TeO 2 -based glass matrix. As a result, QD-embedded glass shows typical bright green emission assigned to exciton recombination radiation and significant improvement of photon/thermal stability and water resistance due to the effective protecting role of dense structural glass. Particularly, ∼90% of emission intensity is even remained after immersing QD-embedded glass in water up to 120 h, enabling them to find promising applications in white-light-emitting device with superior color stability and low-threshold random upconverted laser under ambient air condition.

WhitebalPR: automatic white balance by polarized reflections

NASA Astrophysics Data System (ADS)

Fischer, Gregor; Kolbe, Karin; Sajjaa, Matthias

2008-02-01

This new color constancy method is based on the polarization degree of that light which is reflected at the surface of an object. The subtraction of at least two images taken under different polarization directions detects the polarization degree of the neutrally reflected portions and eliminates the remitted non-polarized colored portions. Two experiments have been designed to clarify the performance of the procedure, one to multicolored objects and another to objects of different surface characteristics. The results show that the mechanism of eliminating the remitted, non-polarized colored portions of light works very fine. Independent from its color, different color pigments seem to be suitable for measuring the color of the illumination. The intensity and also the polarization degree of the reflected light depend on the surface properties significantly. The results exhibit a high accuracy of measuring the color of the illumination for glossy and matt surfaces. Only strongly scattering surfaces account for a weak signal level of the difference image and a reduced accuracy. An embodiment is proposed to integrate the new method into digital cameras.

Quantitative Evaluation of Surface Color of Tomato Fruits Cultivated in Remote Farm Using Digital Camera Images

NASA Astrophysics Data System (ADS)

Hashimoto, Atsushi; Suehara, Ken-Ichiro; Kameoka, Takaharu

To measure the quantitative surface color information of agricultural products with the ambient information during cultivation, a color calibration method for digital camera images and a remote monitoring system of color imaging using the Web were developed. Single-lens reflex and web digital cameras were used for the image acquisitions. The tomato images through the post-ripening process were taken by the digital camera in both the standard image acquisition system and in the field conditions from the morning to evening. Several kinds of images were acquired with the standard RGB color chart set up just behind the tomato fruit on a black matte, and a color calibration was carried out. The influence of the sunlight could be experimentally eliminated, and the calibrated color information consistently agreed with the standard ones acquired in the system through the post-ripening process. Furthermore, the surface color change of the tomato on the tree in a greenhouse was remotely monitored during maturation using the digital cameras equipped with the Field Server. The acquired digital color images were sent from the Farm Station to the BIFE Laboratory of Mie University via VPN. The time behavior of the tomato surface color change during the maturing process could be measured using the color parameter calculated based on the obtained and calibrated color images along with the ambient atmospheric record. This study is a very important step in developing the surface color analysis for both the simple and rapid evaluation of the crop vigor in the field and to construct an ambient and networked remote monitoring system for food security, precision agriculture, and agricultural research.

The effect of high pressure and residual oxygen on the color stability of minced cured restructured ham at different levels of drying, pH, and NaCl.

PubMed

Bak, Kathrine Holmgaard; Lindahl, Gunilla; Karlsson, Anders H; Lloret, Elsa; Gou, Pere; Arnau, Jacint; Orlien, Vibeke

2013-10-01

Color stability of minced cured restructured ham was studied by considering the effects of high pressure (HP) (600 MPa, 13°C, 5 min), raw meat pH24 (low, normal, high), salt content (15, 30 g/kg), drying (20%, 50% weight loss), and residual oxygen level (0.02%-0.30%). Raw hams were selected by pH24 in Semimembranosus, mixed with additives, frozen, sliced, and dried by the Quick-Dry-Slice® (QDS) process followed by HP treatment or not (control). Packaging and storage simulated industrial packaging: modified atmosphere containing 80% N2, 20% CO2, and residual O2 in one of three intervals: <0.1%, 0.1%-0.2%, or 0.2%-0.3%, and retail storage conditions: chill storage, 12 h light, 12 h darkness. HP improved the stability of the redness of 20% QDS hams, while the stabilizing effect on 50% QDS hams was smaller, concluding that water has the dominating role. Raw meat pH24, salt content, and residual oxygen level had varying effects on the stability of the red color. Copyright © 2013 Elsevier Ltd. All rights reserved.

Adsorption behavior of natural anthocyanin dye on mesoporous silica

NASA Astrophysics Data System (ADS)

Kohno, Yoshiumi; Haga, Eriko; Yoda, Keiko; Shibata, Masashi; Fukuhara, Choji; Tomita, Yasumasa; Maeda, Yasuhisa; Kobayashi, Kenkichiro

2014-01-01

Because of its non-toxicity, naturally occurring anthocyanin is potentially suitable as a colorant for foods and cosmetics. To the wider use of the anthocyanin, the immobilization on the inorganic host for an easy handling as well as the improvement of the stability is required. This study is focused on the adsorption of significant amount of the natural anthocyanin dye onto mesoporous silica, and on the stability enhancement of the anthocyanin by the complexation. The anthocyanin has successfully been adsorbed on the HMS type mesoporous silica containing small amount of aluminum. The amount of the adsorbed anthocyanin has been increased by modifying the pore wall with n-propyl group to make the silica surface hydrophobic. The light fastness of the adsorbed anthocyanin has been improved by making the composite with the HMS samples containing aluminum, although the degree of the improvement is not so large. It has been proposed that incorporation of the anthocyanin molecule deep inside the mesopore is required for the further enhancement of the stability.

Running head: What color is it

NASA Technical Reports Server (NTRS)

Young, Andrew T.

1988-01-01

Color vision provides low-resolution spectrophotometric information about candidate materials for planetary surfaces that is comparable in precision to wideband photoelectric photometry, and considerably superior to Voyager TV data. Briefly explained are the basic concepts, teminology, and notation of color science. Also shown is how to convert a reflectance spectrum into a color specification. An Appendix lists a simple computer subroutine to convert spectral reflectance into CIE coordinates, and the text explains how to convert these to a surface color in a standard color atlas. Target and printed Solar System colors are compared to show how accurate are the printed colors.

Structural coloration of chitosan coated cellulose fabrics by electrostatic self-assembled poly (styrene-methyl methacrylate-acrylic acid) photonic crystals.

PubMed

Yavuz, Gönül; Zille, Andrea; Seventekin, Necdet; Souto, Antonio P

2018-08-01

The structural coloration of a chitosan-coated woven cotton fabric obtained by glutaraldehyde-stabilized deposition of electrostatic self-assembled monodisperse and spherically uniform (250 nm) poly (styrene-methyl methacrylate-acrylic acid) photonic crystal nanospheres (P(St-MMA-AA)) was investigated. Bright iridescent coatings displaying different colors in function of the viewing angle were obtained. The SEM, diffuse reflectance spectroscopy, TGA, DSC and FTIR analyses confirm the presence of structural color and the glutaraldehyde and chitosan ability to provide durable chemical bonding between cotton fabric and photonic crystal (PCs) coating with the highest degradation temperature and the lowest enthalpy. The coatings are characterized by a mixture of face-centered cubic and hexagonal close-packed arrays alternating random packing regions. For the first time a cost-efficient structural coloration with high washing and light fastness using self-assembled P(St-MMA-AA) photonic crystals was successfully developed onto woven cotton fabric using chitosan and/or glutaraldehyde as stabilizing agent opening new strategies for the development of dye-free coloration of textiles. Copyright © 2018 Elsevier Ltd. All rights reserved.

High-quality digital color xerography

NASA Astrophysics Data System (ADS)

Takiguchi, Koichi

1993-06-01

Image noise, tone reproduction, color reproduction, fine line reproduction, and OHP performance are the most important characteristics for a high quality color copier. Technologies enabling such quality are use of fine toner, halftone algorithm to ensure good highlight reproduction, soft roll fuser with good release performance, smooth surface and high thermal conductivity, white and smooth paper, and selection of a coating material for the surface layer of the OHP sheets. These technologies are integrated in the Fuji Xerox `A- Color' product. Utilizing 7 micrometers color toner, `A-Color' can make very high quality color copies.

Color selectivity of surface-plasmon holograms illuminated with white light.

PubMed

Ozaki, Miyu; Kato, Jun-ichi; Kawata, Satoshi

2013-09-20

By using the optical frequency dependence of surface-plasmon polaritons, color images can be reconstructed from holograms illuminated with white light. We report details on the color selectivity of the color holograms. The selectivity is tuned by the thickness of a dielectric film covering a plasmonic metal film. When the dielectric is SiO(2) and the metal is silver, the appropriate thicknesses are 25 and 55 nm, respectively. In terms of spatial color uniformity, holograms made of silver-film corrugations are better than holograms recorded on photographic film on a flat silver surface.

Microanalysis of organic pigments and glazes in polychrome works of art by surface-enhanced resonance Raman scattering

PubMed Central

Leona, Marco

2009-01-01

Scientific studies of works of art are usually limited by severe sampling restrictions. The identification of organic colorants, a class of compounds relevant for attribution and provenance studies, is further complicated by the low concentrations at which these compounds are used and by the interference of the protein-, gum-, or oil-binding media present in pigment and glaze samples. Surface-enhanced resonance Raman scattering (SERRS) was successfully used to identify natural organic colorants in archaeological objects, polychrome sculptures, and paintings from samples smaller than 25 μm in diameter. The key factors in achieving the necessary sensitivity were a highly active stabilized silver colloid, obtained by the reproducible microwave-supported reduction of silver sulfate with glucose and sodium citrate, and a non-extractive hydrolysis sample treatment procedure that maximizes dye adsorption on the colloid. Among the examples presented are the earliest so far found occurrence of madder lake (in a 4,000 years old Egyptian object dating to the Middle Kingdom period), and the earliest known occurrence in Europe of the South Asian dyestuff lac (in the Morgan Madonna, a 12th century polychrome sculpture from Auvergne, France). PMID:19667181

Microanalysis of organic pigments and glazes in polychrome works of art by surface-enhanced resonance Raman scattering.

PubMed

Leona, Marco

2009-09-01

Scientific studies of works of art are usually limited by severe sampling restrictions. The identification of organic colorants, a class of compounds relevant for attribution and provenance studies, is further complicated by the low concentrations at which these compounds are used and by the interference of the protein-, gum-, or oil-binding media present in pigment and glaze samples. Surface-enhanced resonance Raman scattering (SERRS) was successfully used to identify natural organic colorants in archaeological objects, polychrome sculptures, and paintings from samples smaller than 25 microm in diameter. The key factors in achieving the necessary sensitivity were a highly active stabilized silver colloid, obtained by the reproducible microwave-supported reduction of silver sulfate with glucose and sodium citrate, and a non-extractive hydrolysis sample treatment procedure that maximizes dye adsorption on the colloid. Among the examples presented are the earliest so far found occurrence of madder lake (in a 4,000 years old Egyptian object dating to the Middle Kingdom period), and the earliest known occurrence in Europe of the South Asian dyestuff lac (in the Morgan Madonna, a 12th century polychrome sculpture from Auvergne, France).

Color-Tunable ZnO/GaN Heterojunction LEDs Achieved by Coupling with Ag Nanowire Surface Plasmons.

PubMed

Yang, Liu; Wang, Yue; Xu, Haiyang; Liu, Weizhen; Zhang, Cen; Wang, Chunliang; Wang, Zhongqiang; Ma, Jiangang; Liu, Yichun

2018-05-09

Color-tunable light-emitting devices (LEDs) have a great impact on our daily life. Herein, LEDs with tunable electroluminescence (EL) color were achieved via introducing Ag nanowires surface plasmons into p-GaN/n-ZnO film heterostructures. By optimizing the surface coverage density of coated Ag nanowires, the EL color was changed continuously from yellow-green to blue-violet. Transient-state and temperature-variable fluorescence emission characterizations uncovered that the spontaneous emission rate and the internal quantum efficiency of the near-UV emission were increased as a consequence of the resonance coupling interaction between Ag nanowires surface plasmons and ZnO excitons. This effect induces the selective enhancement of the blue-violet EL component but suppresses the defect-related yellow-green emission, leading to the observed tunable EL color. The proposed strategy of introducing surface plasmons can be further applied to many other kinds of LEDs for their selective enhancement of EL intensity and effective adjustment of the emission color.

Analysis of ingredient functionality and formulation optimization of an instant peanut beverage mix.

PubMed

Howard, Brandy M; Hung, Yen-Con; McWatters, S Kay

2010-01-01

Powder for an instant shake-style beverage was created using partially defatted peanut flour (12% fat), granulated sugar, and nonfat dry milk (NFDM). The 3 main components, along with constant amounts of stabilizing gums and anti-caking silica, were mixed together and finely milled in a Super Wing Mill to further reduce the particle sizes. Drinks from each formula variation were prepared and analyzed for viscosity (digital viscometer), color (colorimeter), and separation rate. Each beverage was also analyzed by consumers to determine acceptability of flavor, mouth-feel, and color. Physical test results show that viscosity increased with increasing proportion of peanut flour in the formula, and viscosity decreased with increasing levels of sugar and NFDM. For each formula, the samples at refrigerated temperature (4 degrees C) were less viscous than those at ambient temperatures (23 to 25 degrees C). Color values show that the beverage powder color was mostly influenced by peanut flour percentage, becoming darker with increasing levels of peanut flour. Prepared beverage color was influenced by both NFDM and peanut flour percentage; lightness increased with increasing NFDM percentage and decreased with increasing peanut flour percentage. Separation rates were most affected by the proportion of NFDM in the formula; higher levels decreased the rate of separation. Refrigeration slowed the rate of separation in all samples. Response surface analysis of consumer test data showed that the most acceptable formulation for the peanut beverage included approximately equal amounts of peanut flour, sugar, and NFDM.

The Effect of Preventive Agents (Mouthwashes/Gels) on the Color Stability of Dental Resin-Based Composite Materials

PubMed Central

Al-Samadani, Khalid H.

2017-01-01

The color of dental restorative material should be maintained throughout its functional lifetime in an oral environment. However, the frequent use of mouthwash may affect the color stability of these composite restorations. The aim of this study is to assess the effects of using various mouthwashes on the color stability of various dental restorative composite materials. For this purpose, four mouthwashes/gels (Flocare gel (0.4% stannous fluoride), Pascal gel (topical APF fluoride), Pro-Relief mouthwash (sodium fluoride), and Plax Soin mouthwash (sodium fluoride)), and distilled water as a control, were selected. These were divided into five groups: Group 1: Flocare gel; Group 2: Pascal gel; Group 3: Pro-Relief mouthwash; Group 4: Plax Soin mouthwash; and Group 5: distilled water (control). Prepared restorative materials samples were immersed in the groups of mouthwashes/gels and the distilled water (control) for 24, 48, and 72 h. The discoloration that all materials exhibited with all immersion groups was significantly different at each of the three time periods for all groups (p < 0.05). Results from immersion in Flocare gel, Pascal gel, Pro-Relief mouthwash, and Plax Soin mouthwash were statistically significant (p < 0.05). The color change chroma was not significant for Pro-Relief and Plax Soin mouthwash (p > 0.05). Mouthwashes/gels affect color shifting for all composite resin materials, and changes are exaggerated over time. However, discoloration effects are not perceptible to the human eye. PMID:29563424

In vivo quantitative evaluation of tooth color with hand-held colorimeter and custom template.

PubMed

Shimada, Kazuki; Kakehashi, Yoshiyuki; Matsumura, Hideo; Tanoue, Naomi

2004-04-01

This article presents a technique for quantitatively evaluating the color of teeth, as well as color change in restorations and tooth surfaces. Through use of a custom template made of a thermoplastic polymer and a dental colorimeter, tooth surface color can be recorded periodically at the same location intraorally.

Neural representation of form-contingent color filling-in in the early visual cortex.

PubMed

Hong, Sang Wook; Tong, Frank

2017-11-01

Perceptual filling-in exemplifies the constructive nature of visual processing. Color, a prominent surface property of visual objects, can appear to spread to neighboring areas that lack any color. We investigated cortical responses to a color filling-in illusion that effectively dissociates perceived color from the retinal input (van Lier, Vergeer, & Anstis, 2009). Observers adapted to a star-shaped stimulus with alternating red- and cyan-colored points to elicit a complementary afterimage. By presenting an achromatic outline that enclosed one of the two afterimage colors, perceptual filling-in of that color was induced in the unadapted central region. Visual cortical activity was monitored with fMRI, and analyzed using multivariate pattern analysis. Activity patterns in early visual areas (V1-V4) reliably distinguished between the two color-induced filled-in conditions, but only higher extrastriate visual areas showed the predicted correspondence with color perception. Activity patterns allowed for reliable generalization between filled-in colors and physical presentations of perceptually matched colors in areas V3 and V4, but not in earlier visual areas. These findings suggest that the perception of filled-in surface color likely requires more extensive processing by extrastriate visual areas, in order for the neural representation of surface color to become aligned with perceptually matched real colors.

Effect of varying core thicknesses and artificial aging on the color difference of different all-ceramic materials.

PubMed

Dikicier, Sibel; Ayyildiz, Simel; Ozen, Julide; Sipahi, Cumhur

2014-11-01

Clinicians should reserve all-ceramics with high translucency for clinical applications in which high-level esthetics are required. Furthermore, it is unclear whether a correlation exists between core thickness and color change. The aim of this study was to examine the effects of different core thicknesses and artificial aging on the color stability of three all-ceramic systems. Ninety disc-shaped cores with different thicknesses (0.5 mm, 0.8 mm and 1.0 mm) were prepared from three all-ceramic systems, In-Ceram Alumina (IC), IPS e.max Press (EM) and Katana (K). The colors of the samples were measured with a spectrophotometer and the color parameters (L*, a*, b*, ΔE) were calculated according to the CIE L*a*b* (Commission Internationale de L'Eclairage) color system before and after aging. The effects of aging on color parameters were statistically significant (p < 0.001), regardless of core thickness. For all systems, the CIE a* values increased as the thickness of the core increased. Conversely, such increases in core porcelain thickness were correlated with decreasing CIE L* and b* values. Core thickness had a statistically significant effect on color change among the groups. Different core thicknesses (from 1.0-0.5 mm) and artificial aging affected color stability of the all-ceramic materials tested.

Influence of prefermentative cold maceration on the color and anthocyanic copigmentation of organic Tempranillo wines elaborated in a warm climate.

PubMed

Gordillo, Belen; López-Infante, M Isabel; Ramírez-Pérez, Pilar; González-Miret, M Lourdes; Heredia, Francisco J

2010-06-09

The stabilization of red wine color by the copigmentation phenomenon is a crucial process that does not always proceed favorably under natural conditions during the first stages of vinification. The impact of the prefermentative cold maceration technique on the phenolic composition and magnitude of the copigmentation level of organic Tempranillo wines elaborated in a warm climate have been studied as an enological alternative to the traditional maceration for obtaining highly colored wines. Tristimulus colorimetry was applied to study the color of wines during vinification, and a high-performance liquid chromatography (HPLC) procedure was used for the analysis of phenolic compounds. Spectrophotometric and colorimetric analyses were also performed to evaluate the copigmentation level of the wines. Significant chemical and color differences were found depending on the maceration technique applied. Prefermentative cold macerated wines were richer in those compounds accounting directly for the color of red wine (anthocyanins) and those involved in anthocyanin stabilization through copigmentation reactions (phenols), which was in accordance with the higher copigmentation degree and darker, more saturated and vivid bluish colors. The evaluation of the copigmentation based on colorimetric parameters in the CIELAB color space showed that prefermentative cold maceration caused greater effectiveness of copigmentation than traditional maceration since it induces more important and hence more easily perceptible color changes.

Face recognition using 3D facial shape and color map information: comparison and combination

NASA Astrophysics Data System (ADS)

Godil, Afzal; Ressler, Sandy; Grother, Patrick

2004-08-01

In this paper, we investigate the use of 3D surface geometry for face recognition and compare it to one based on color map information. The 3D surface and color map data are from the CAESAR anthropometric database. We find that the recognition performance is not very different between 3D surface and color map information using a principal component analysis algorithm. We also discuss the different techniques for the combination of the 3D surface and color map information for multi-modal recognition by using different fusion approaches and show that there is significant improvement in results. The effectiveness of various techniques is compared and evaluated on a dataset with 200 subjects in two different positions.

Comparison of spice-derived antioxidants and metal chelators on fresh beef color stability.

PubMed

Allen, Karin; Cornforth, Daren

2010-08-01

Effects of Type I antioxidants eugenol and rosmarinic acid were compared to those of Type II antioxidants milk mineral (MM), sodium tripolyphosphpate (STPP), and phytate in raw ground beef held for 14 days at 4 degrees C in oxygen-permeable polyvinylchloride. Meat color stability was measured as % oxymyoglobin, Hunter a * value, chroma, and hue angle. Significant correlations (P<0.0001) were observed between all color measurement methods. By day 14, STPP-treated patties lost more red color (P<0.05 for a* and hue angle) and had higher thiobarbituric acid values than other treatments. By day 14, MM was as effective as eugenol and rosmarinate at preventing oxymyoglobin oxidation (72, 76, and 71% retained, respectively) and red color loss as measured by a * (9.2, 9.4, and 10.9), hue angle (58.4, 56.2, and 53.5), and chroma (17, 17, and 18), but was unable to inhibit microbial growth as effectively as the spice-derived antioxidants. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

Evaluation of the effect of various beverages and food material on the color stability of provisional materials - An in vitro study.

PubMed

Gupta, Gaurav; Gupta, Tina

2011-07-01

THIS STUDY EVALUATED THE COLOR STABILITY OF FOUR PROVISIONAL MATERIALS: 1) Poly-methyl methacrylates (DPI); 2) Bis-acryl composite (ProtempTM II - 3M ESPE); 3) Bis-acryl composite (Systemp® c and b - Ivoclar Vivadent) and 4) Light polymerized composite resin (Revotek LC- GC). The color and color difference of each specimen after immersion in different staining solutions i.e. 1) tea and artificial saliva, 2) coffee and artificial saliva, 3) Pepsi and artificial saliva, 4) turmeric solution and artificial saliva was measured using reflectance spectrophotometer with CIELAB system before immersion and after immersion at 2, 5 ,7 , 10 and 15 days. Revotek LC- GC (light polymerized composite resin) was found to be the most color stable provisional restorative material followed by Protemp II (Bis-acryl composite), Systemp (Bis-acryl composite) and DPI (Methylmethacrylate resin). Turmeric solution had the maximum staining potential followed by coffee, tea and Pepsi.

Evaluation of the effect of various beverages and food material on the color stability of provisional materials – An in vitro study

PubMed Central

Gupta, Gaurav; Gupta, Tina

2011-01-01

Aim: This study evaluated the color stability of four provisional materials: 1) Poly-methyl methacrylates (DPI); 2) Bis-acryl composite (ProtempTM II – 3M ESPE); 3) Bis-acryl composite (Systemp® c and b – Ivoclar Vivadent) and 4) Light polymerized composite resin (Revotek LC- GC). Materials and Methods: The color and color difference of each specimen after immersion in different staining solutions i.e. 1) tea and artificial saliva, 2) coffee and artificial saliva, 3) Pepsi and artificial saliva, 4) turmeric solution and artificial saliva was measured using reflectance spectrophotometer with CIELAB system before immersion and after immersion at 2, 5 ,7 , 10 and 15 days. Results: Revotek LC- GC (light polymerized composite resin) was found to be the most color stable provisional restorative material followed by Protemp II (Bis-acryl composite), Systemp (Bis-acryl composite) and DPI (Methylmethacrylate resin). Turmeric solution had the maximum staining potential followed by coffee, tea and Pepsi. PMID:22025835

Color and chemistry on Triton

NASA Technical Reports Server (NTRS)

Thompson, W. Reid; Sagan, Carl

1990-01-01

The surface of Triton is very bright but shows subtle yellow to peach hues which probably arise from the production of colored organic compounds from CH4 + N2 and other simple species. In order to investigate possible relationships between chemical processes and the observed surface distribution of chromophores, the surface units are classified according to color/albedo properties, the rates of production of organic chromophores by the action of ultraviolet light and high-energy charged particles is estimated, and rates, spectral properties, and expected seasonal redistribution processes are compared to suggest possible origins of the colors seen on Triton's surface.

Bench-scale evaluation of drinking water treatment parameters on iron particles and water quality.

PubMed

Rahman, M Safiur; Gagnon, Graham A

2014-01-01

Discoloration of water resulting from suspended iron particles is one of the main customer complaints received by water suppliers. However, understanding of the mechanisms of discoloration as well as role of materials involved in the process is limited. In this study, an array of bench scale experiments were conducted to evaluate the impact of the most common variables (pH, PO4, Cl2 and DOM) on the properties of iron particles and suspensions derived from the oxygenation of Fe(II) ions in NaHCO3 buffered synthetic water systems. The most important factors as well as their rank influencing iron suspension color and turbidity formation were identified for a range of water quality parameters. This was accomplished using a 2(4) full factorial design approach at a 95% confidence level. The statistical analysis revealed that phosphate was found to be the most significant factor to alter color (contribution: 37.9%) and turbidity (contribution: 45.5%) in an iron-water system. A comprehensive study revealed that phosphate and chlorine produced iron suspension with reduced color and turbidity, made ζ-potential more negative, reduced the average particle size, and increased iron suspension stability. In the presence of DOM, color was observed to increase but a reverse trend was observed to decrease the turbidity and to alter particle size distribution. HPSEC results suggest that higher molecular weight fractions of DOM tend to adsorb onto the surfaces of iron particles at early stages, resulting in alteration of the surface charge of iron particles. This in turn limits particles aggregation and makes iron colloids highly stable. In the presence of a phosphate based corrosion inhibitor, this study demonstrated that color and turbidity resulting from suspended iron were lower at a pH value of 6.5 (compared to pH of 8.5). The same trend was observed in presence of DOM. This study also suggested that iron colloid suspension color and turbidity in chlorinated drinking water systems could be lower than non-chlorinated systems. Copyright © 2013 Elsevier Ltd. All rights reserved.

Color Constancy of Red-Green Dichromats and Anomalous Trichromats

PubMed Central

Foster, David H.; Amano, Kinjiro; Nascimento, Sérgio M. C.

2010-01-01

Purpose. Color-vision deficiency is associated with abnormalities in color matching and color discrimination, but its impact on the ability of people to judge the constancy of surface colors under different lights (color constancy) is less clear. This work had two aims: first, to quantify the degree of color constancy in subjects with congenital red-green color deficiency; second, to test whether the degree of color constancy in anomalous trichromats can be predicted from their Rayleigh anomaloscope matches. Methods. Color constancy of red-green color-deficient subjects was tested in a task requiring the discrimination of illuminant changes from surface-reflectance changes. Mondrian-like colored patterns, generated on the screen of a computer monitor, were used as stimuli to avoid the spatial cues provided by natural objects and scenes. Spectral reflectances were taken from the Munsell Book of Color and from natural scenes. Illuminants were taken from the daylight locus. Results. Protanopes and deuteranopes performed more poorly than normal trichromats with Munsell spectral reflectances but were less impaired with natural spectral reflectances. Protanomalous and deuteranomalous trichromats performed as well as, or almost as well as, normal trichromats, independent of the type of reflectance. Individual differences were not correlated with Rayleigh anomaloscope matches. Conclusions. Despite the evidence of clinical color-vision tests, red-green color-deficient persons are less disadvantaged than might be expected in their judgments of surface colors under different lights. PMID:19892868

Space weathering and the color indexes of minor bodies in the outer Solar System

NASA Astrophysics Data System (ADS)

Kaňuchová, Zuzana; Brunetto, Rosario; Melita, Mario; Strazzulla, Giovanni

2012-09-01

The surfaces of small bodies in the outer Solar System are rich in organic compounds and carbonaceous refractories mixed with ices and silicates. As made clear by dedicated laboratory experiments space weathering (e.g. energetic ion bombardment) can produce red colored materials starting from bright and spectrally flat ices. In a classical scenario, the space weathering processes “nurture” alter the small bodies surface spectra but are in competition with resurfacing agents that restore the original colors, and the result of these competing processes continuously modifying the surfaces is supposed to be responsible for the observed spectral variety of those small bodies. However an alternative point of view is that the different colors are due to “nature” i.e. to the different primordial composition of different objects. In this paper we present a model, based on laboratory results, that gives an original contribution to the “nature” vs. “nurture” debate by addressing the case of surfaces showing different fractions of rejuvenated vs. space weathered surface, and calculating the corresponding color variations. We will show how a combination of increasing dose coupled to different resurfacing can reproduce the whole range of observations of small outer Solar System bodies. Here we demonstrate, for the first time that objects having a fully weathered material turn back in the color-color diagrams. At the same time, object with the different ratio of pristine and weathered surface areas lay on specific lines in color-color diagrams, if exposed to the same amount of irradiation.

7 CFR 51.1860 - Color classification.

Code of Federal Regulations, 2010 CFR

2010-01-01

... variety: (1) Green. “Green” means that the surface of the tomato is completely green in color. The shade of green color may vary from light to dark; (2) Breakers. “Breakers” means that there is a definite break in color from green to tannish-yellow, pink or red on not more than 10 percent of the surface; (3...

Effects of polishing on surface roughness, gloss, and color of resin composites.

PubMed

Hosoya, Yumiko; Shiraishi, Takanobu; Odatsu, Tetsuro; Nagafuji, Junichi; Kotaku, Mayumi; Miyazaki, Masashi; Powers, John M

2011-09-01

This study evaluated the effects of polishing on surface roughness, gloss, and color of regular, opaque, and enamel shades for each of three resin composites. Two-mm-thick resin disks made with Estelite Σ Quick, Clearfil Majesty, and Beautifil II were final polished with 180-, 1000-, and 3000-grit silicon carbide paper. Surface roughness, gloss, and color were measured one week after curing. Estelite Σ Quick had significantly lower roughness values and significantly higher gloss values as compared with Clearfil Majesty and Beautifil II. The effects of surface roughness and gloss on color (L*a*b*) differed among resin composites and by shade. Correlation coefficients between surface roughness and L*a*b* color factors were generally high for Clearfil Majesty, partially high (i.e., between roughness and L*) for Beautifil II, and low for Estelite Σ Quick. Correlation coefficients between gloss and L*a*b* color parameters were generally high for Beautifil II and low for Estelite Σ Quick and Clearfil Majesty. However, for all resin composites, the values of the color differences between 3000-grit and 180-grit polishing groups for all shades were imperceptible by the naked eye.

Comparative evaluation of the stability of seven-transmembrane microbial rhodopsins to various physicochemical stimuli

NASA Astrophysics Data System (ADS)

Honda, Naoya; Tsukamoto, Takashi; Sudo, Yuki

2017-08-01

Rhodopsins are seven-transmembrane proteins that function as photoreceptors for a variety of biological processes. Their characteristic visible colors make rhodopsins a good model for membrane-embedded proteins. In this study, by utilizing their color changes, we performed comparative studies on the stability of five microbial rhodopsins using the same instruments, procedures and media. As denaturants, we employed four physicochemical stimuli: (i) thermal perturbation, (ii) the water-soluble reagent hydroxylamine, (iii) the detergent sodium dodecyl sulfate, and (iv) the organic solvent ethanol. On the basis of the results, models for stabilization mechanisms in rhodopsins against each stimulus is proposed.

Double channel emission from a redox active single component quantum dot complex.

PubMed

Bhandari, Satyapriya; Roy, Shilaj; Pramanik, Sabyasachi; Chattopadhyay, Arun

2015-01-13

Herein we report the generation and control of double channel emission from a single component system following a facile complexation reaction between a Mn(2+) doped ZnS colloidal quantum dot (Qdot) and an organic ligand (8-hydroxy quinoline; HQ). The double channel emission of the complexed quantum dot-called the quantum dot complex (QDC)-originates from two independent pathways: one from the complex (ZnQ2) formed on the surface of the Qdot and the other from the dopant Mn(2+) ions of the Qdot. Importantly, reaction of ZnQ2·2H2O with the Qdot resulted in the same QDC formation. The emission at 500 nm with an excitation maximum at 364 nm is assigned to the surface complex involving ZnQ2 and a dangling sulfide bond. On the other hand, the emission at 588 nm-with an excitation maximum at 330 nm-which is redox tunable, is ascribed to Mn(2+) dopant. The ZnQ2 complex while present in QDC has superior thermal stability in comparison to the bare complex. Interestingly, while the emission of Mn(2+) was quenched by an electron quencher (benzoquinone), that due to the surface complex remained unaffected. Further, excitation wavelength dependent tunability in chromaticity color coordinates makes the QDC a potential candidate for fabricating a light emitting device of desired color output.

Metal surface coloration by oxide periodic structures formed with nanosecond laser pulses

NASA Astrophysics Data System (ADS)

Veiko, Vadim; Karlagina, Yulia; Moskvin, Mikhail; Mikhailovskii, Vladimir; Odintsova, Galina; Olshin, Pavel; Pankin, Dmitry; Romanov, Valery; Yatsuk, Roman

2017-09-01

In this work, we studied a method of laser-induced coloration of metals, where small-scale spatially periodic structures play a key role in the process of color formation. The formation of such structures on a surface of AISI 304 stainless steel was demonstrated for the 1.06 μm fiber laser with nanosecond duration of pulses and random (elliptical) polarization. The color of the surface depends on the period, height and orientation of periodic surface structures. Adjustment of the polarization of the laser radiation or change of laser incidence angle can be used to control the orientation of the structures. The formation of markings that change their color under the different viewing angles becomes possible. The potential application of the method is metal product protection against falsification.

Use of visible and near-infrared spectroscopy to predict pork longissimus lean color stability.

PubMed

King, D A; Shackelford, S D; Wheeler, T L

2011-12-01

This study evaluated the use of visible and near-infrared (VISNIR) spectroscopy to predict lean color stability in pork loin chops. Spectra were collected immediately after and approximately 1 h after rib removal on 1,208 loins. Loins were aged for 14 d before a 2.54-cm chop was placed in simulated retail display. Spectra were collected on aged loins immediately after removal from the vacuum package and on chops 10 min after cutting. Instrumental color measurements [L*, a*, b*, hue angle, chroma, and E (overall color change)] were determined on d 0, 1, 7, 11, and 14 of display. Principal components analysis of display d 0 and 14 values of these traits identified a factor (first principal component; PC1) explaining 67% of the variance that was related to color change. Partial least squares regression was used to develop 3 models to predict PC1 values by using VISNIR spectra collected in the plant, on aged loins, and on chops. Loins with predicted PC1 values less than 0 were classified as having a stable color, whereas values greater than 0 were classified as having a labile lean color. Loins classified as stable by the in-plant model had smaller (P < 0.05) L* values than those classified as labile. Hue angle and ΔE values were less (P < 0.05) and a* and chroma values were greater (P < 0.05) after d 7 of display in loins predicted to have a stable color than in loins predicted to have a labile lean color. Similarly, chops from loins classified as stable using the aged loin model had smaller (P < 0.05) L* values than those from loins classified as labile. Furthermore, loins predicted to be stable had smaller (P < 0.05) hue angle and ΔE values and greater (P < 0.05) a* and chroma values after d 7 of display than did loins predicted to be labile. Results for the chop model were similar to those from the 2 loin models. Chops predicted to have a stable lean color had smaller (P < 0.05) L* values than did those predicted to have a labile lean color. Chops classified as stable had smaller (P < 0.05) hue angle and ΔE values and greater (P < 0.05) a* and chroma values after d 7 of display compared with chops classified as labile. All 3 models effectively segregated chops based on color stability, particularly with regard to redness. Regardless of the model being used, d 14 display values for a*, hue angle, and ΔE in loins classified as stable were similar to the d 7 values of loins classified as labile. Thus, these results suggest that VISNIR spectroscopy would be an effective technology for sorting pork loins with regard to lean color stability.

Color stability of CAD/CAM Zirconia ceramics following exposure to acidic and staining drinks

PubMed Central

Colombo, Marco; Cavallo, Marco; Miegge, Matteo; Dagna, Alberto; Beltrami, Riccardo; Chiesa, Marco

2017-01-01

Background The aim of this in vitro study was to evaluate the color stability of CAD/CAM Zirconia ceramics following exposure to acidic drink (Coca Cola) and after exposure to staining solution (coffee). Material and Methods All the samples were immersed in different staining solutions over a 28-day test period. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. Shapiro Wilk test and Kruskal-Wallis ANOVA were applied to assess significant differences among restorative materials. Paired t-test was applied to test which CIE L*a*b* parameters significantly changed after immersion in staining solutions. Results One week immersion in acidic drink did not cause a perceivable discoloration for all restorative materials (ΔE < 3.3). Subsequent immersion in coffee affected color stability of all Zirconia samples, even if Kruskal-Wallis ANOVA found significant differences among the various restorative materials. Conclusions The ∆Es of CAD/CAM Zirconia ceramics after immersion in coffee varied among the products, but color integrity is not affected by contact with acidic drinks. Key words:CAD/CAM restorative materials, CIE Lab, Zirconia ceramics. PMID:29302281

Color stability of CAD/CAM Zirconia ceramics following exposure to acidic and staining drinks.

PubMed

Colombo, Marco; Cavallo, Marco; Miegge, Matteo; Dagna, Alberto; Beltrami, Riccardo; Chiesa, Marco; Poggio, Claudio

2017-11-01

The aim of this in vitro study was to evaluate the color stability of CAD/CAM Zirconia ceramics following exposure to acidic drink (Coca Cola) and after exposure to staining solution (coffee). All the samples were immersed in different staining solutions over a 28-day test period. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. Shapiro Wilk test and Kruskal-Wallis ANOVA were applied to assess significant differences among restorative materials. Paired t-test was applied to test which CIE L*a*b* parameters significantly changed after immersion in staining solutions. One week immersion in acidic drink did not cause a perceivable discoloration for all restorative materials (ΔE < 3.3). Subsequent immersion in coffee affected color stability of all Zirconia samples, even if Kruskal-Wallis ANOVA found significant differences among the various restorative materials. The ∆Es of CAD/CAM Zirconia ceramics after immersion in coffee varied among the products, but color integrity is not affected by contact with acidic drinks. Key words: CAD/CAM restorative materials, CIE Lab, Zirconia ceramics.

Chemically-Tailored Surfaces of Silica Gel and Alumina Examined Using Color

ERIC Educational Resources Information Center

Taralp, Alpay; Buyukbayram, Gulen; Armagan, Onsel; Yalcin, Ender

2004-01-01

Color is used for studying the chemically-tailored surfaces of silica gel and alumina. When this technique of using color was applied by the students, they were able to grasp the principles of surface engineering and acquire an appreciation of its merits and at the same time they were able to learn the fundamentals of aldehyde chemistry,…

The effect of repeated firings on the color change of dental ceramics using different glazing methods

PubMed Central

Yılmaz, Kerem; Ozturk, Caner

2014-01-01

PURPOSE Surface color is one of the main criteria to obtain an ideal esthetic. Many factors such as the type of the material, surface specifications, number of firings, firing temperature and thickness of the porcelain are all important to provide an unchanged surface color in dental ceramics. The aim of this study was to evaluate the color changes in dental ceramics according to the material type and glazing methods, during the multiple firings. MATERIALS AND METHODS Three different types of dental ceramics (IPS Classical metal ceramic, Empress Esthetic and Empress 2 ceramics) were used in the study. Porcelains were evaluated under five main groups according to glaze and natural glaze methods. Color changes (ΔE) and changes in color parameters (ΔL, Δa, Δb) were determined using colorimeter during the control, the first, third, fifth, and seventh firings. The statistical analysis of the results was performed using ANOVA and Tukey test. RESULTS The color changes which occurred upon material-method-firing interaction were statistically significant (P<.05). ΔE, ΔL, Δa and Δb values also demonstrated a negative trend. The MC-G group was less affected in terms of color changes compared to other groups. In all-ceramic specimens, the surface color was significantly affected by multiple firings. CONCLUSION Firing detrimentally affected the structure of the porcelain surface and hence caused fading of the color and prominence of yellow and red characters. Compressible all-ceramics were remarkably affected by repeated firings due to their crystalline structure. PMID:25551001

Evaluation and improvement of micro-surfacing mix design method and modelling of asphalt emulsion mastic in terms of filler-emulsion interaction

NASA Astrophysics Data System (ADS)

Robati, Masoud

This Doctorate program focuses on the evaluation and improving the rutting resistance of micro-surfacing mixtures. There are many research problems related to the rutting resistance of micro-surfacing mixtures that still require further research to be solved. The main objective of this Ph.D. program is to experimentally and analytically study and improve rutting resistance of micro-surfacing mixtures. During this Ph.D. program major aspects related to the rutting resistance of micro-surfacing mixtures are investigated and presented as follow: 1) evaluation of a modification of current micro-surfacing mix design procedures: On the basis of this effort, a new mix design procedure is proposed for type III micro-surfacing mixtures as rut-fill materials on the road surface. Unlike the current mix design guidelines and specification, the new mix design is capable of selecting the optimum mix proportions for micro-surfacing mixtures; 2) evaluation of test methods and selection of aggregate grading for type III application of micro-surfacing: Within the term of this study, a new specification for selection of aggregate grading for type III application of micro-surfacing is proposed; 3) evaluation of repeatability and reproducibility of micro-surfacing mixture design tests: In this study, limits for repeatability and reproducibility of micro-surfacing mix design tests are presented; 4) a new conceptual model for filler stiffening effect on asphalt mastic of micro-surfacing: A new model is proposed, which is able to establish limits for minimum and maximum filler concentrations in the micro-surfacing mixture base on only the filler important physical and chemical properties; 5) incorporation of reclaimed asphalt pavement and post-fabrication asphalt shingles in micro-surfacing mixture: The effectiveness of newly developed mix design procedure for micro-surfacing mixtures is further validated using recycled materials. The results present the limits for the use of RAP and RAS amount in micro-surfacing mixtures; 6) new colored micro-surfacing formulations with improved durability and performance: The significant improvement of around 45% in rutting resistance of colored and conventional micro-surfacing mixtures is achieved through employing low penetration grade bitumen polymer modified asphalt emulsion stabilized using nanoparticles.

Improved data visualization techniques for analyzing macromolecule structural changes.

PubMed

Kim, Jae Hyun; Iyer, Vidyashankara; Joshi, Sangeeta B; Volkin, David B; Middaugh, C Russell

2012-10-01

The empirical phase diagram (EPD) is a colored representation of overall structural integrity and conformational stability of macromolecules in response to various environmental perturbations. Numerous proteins and macromolecular complexes have been analyzed by EPDs to summarize results from large data sets from multiple biophysical techniques. The current EPD method suffers from a number of deficiencies including lack of a meaningful relationship between color and actual molecular features, difficulties in identifying contributions from individual techniques, and a limited ability to be interpreted by color-blind individuals. In this work, three improved data visualization approaches are proposed as techniques complementary to the EPD. The secondary, tertiary, and quaternary structural changes of multiple proteins as a function of environmental stress were first measured using circular dichroism, intrinsic fluorescence spectroscopy, and static light scattering, respectively. Data sets were then visualized as (1) RGB colors using three-index EPDs, (2) equiangular polygons using radar charts, and (3) human facial features using Chernoff face diagrams. Data as a function of temperature and pH for bovine serum albumin, aldolase, and chymotrypsin as well as candidate protein vaccine antigens including a serine threonine kinase protein (SP1732) and surface antigen A (SP1650) from S. pneumoniae and hemagglutinin from an H1N1 influenza virus are used to illustrate the advantages and disadvantages of each type of data visualization technique. Copyright © 2012 The Protein Society.

Improved data visualization techniques for analyzing macromolecule structural changes

PubMed Central

Kim, Jae Hyun; Iyer, Vidyashankara; Joshi, Sangeeta B; Volkin, David B; Middaugh, C Russell

2012-01-01

The empirical phase diagram (EPD) is a colored representation of overall structural integrity and conformational stability of macromolecules in response to various environmental perturbations. Numerous proteins and macromolecular complexes have been analyzed by EPDs to summarize results from large data sets from multiple biophysical techniques. The current EPD method suffers from a number of deficiencies including lack of a meaningful relationship between color and actual molecular features, difficulties in identifying contributions from individual techniques, and a limited ability to be interpreted by color-blind individuals. In this work, three improved data visualization approaches are proposed as techniques complementary to the EPD. The secondary, tertiary, and quaternary structural changes of multiple proteins as a function of environmental stress were first measured using circular dichroism, intrinsic fluorescence spectroscopy, and static light scattering, respectively. Data sets were then visualized as (1) RGB colors using three-index EPDs, (2) equiangular polygons using radar charts, and (3) human facial features using Chernoff face diagrams. Data as a function of temperature and pH for bovine serum albumin, aldolase, and chymotrypsin as well as candidate protein vaccine antigens including a serine threonine kinase protein (SP1732) and surface antigen A (SP1650) from S. pneumoniae and hemagglutinin from an H1N1 influenza virus are used to illustrate the advantages and disadvantages of each type of data visualization technique. PMID:22898970

Completely open-foldable domes remaining cool in sunshine

NASA Astrophysics Data System (ADS)

Hammerschlag, Robert H.; Deelen, Sander; Hoogendoorn, Pieter W.; Kommers, Johannes N. M.; Sonner, Thomas; Simoes, Roberto; Grassin, Olivier; Fischer, Andreas; Visser, Simon; Thewissen, Kristof

2016-07-01

These open-foldable very light-weight domes, based on very strong textile membranes highly tensioned between steel bows, are designed for bad-weather protection and maintenance of instruments for astronomical, meteorological and civil-engineering measurements and have extremely high wind stability. The domes of the GREGOR telescope and the Dutch Open Telescope are the two existing prototypes. Improvements were developed with all parts light-colored to remain cool in solar light. The new specially made connection parts (eyes) between the textile parts are made from white-colored PETP, a very strong and UV-stable synthetic, and have a better geometrical shape giving higher stability. The rubber seal tubes on top of the dome were of black-colored chloride rubber CR (neoprene), strong and UV stable, but very warm in sunlight. New UV-stable EPDM rubber tubes were produced in natural light color. To get this rubber stiff enough to give good sealing, a black-colored stiff EPDM rubber is put inside the light-colored one. Tests were performed and the forces necessary for compression of the rubber tubes were measured. An inside black tube with a circa 1.3 times larger compression force than the original black tubes was applied. The assembling of the black tubes into the light-colored tubes was successfully applied at the DOT and GREGOR domes.

Pigment and color stability of beetroot betalains in cow milk during thermal treatment.

PubMed

Güneşer, Onur

2016-04-01

Thermal stability of beetroot betalains in cow milk was determined during heating at 70-90 °C. Changes in color values of colored milk were also investigated. Degradation of betalains followed first order kinetics while changes of L(∗), Hue angle and Chroma values fitted zero order and first order kinetic, respectively. Reaction rate for degradation of betalains, L(∗), Hue angle and Chroma values ranged between 1.588-30.975 × 10(-3) min(-1), 90.50-379.75 L(∗)min(-1), 0.581-5.008 Hue anglemin(-1) and 3.250-19.750 × 10(-3) min(-1), respectively. Between 70 and 90 °C, activation energy for the degradation of betalains was 42.449 kJ mol(-1). L(∗) values was more stable than Hue angle and Chroma color values in colored milk during heating. 74.150 kJ mol(-1), 111.174 kJ mol(-1) and 93.311 kJ mol(-1) of activation energy values were found for L(∗), Hue angle and Chroma values of milk, respectively. Significant positive and negative linear correlations were determined between betalains and color values. Multiple regression models were also established to predict the content of betalains in milk during thermal process by using color values. Copyright © 2015 Elsevier Ltd. All rights reserved.

Nanosecond laser coloration on stainless steel surface.

PubMed

Lu, Yan; Shi, Xinying; Huang, Zhongjia; Li, Taohai; Zhang, Meng; Czajkowski, Jakub; Fabritius, Tapio; Huttula, Marko; Cao, Wei

2017-08-02

In this work, we present laser coloration on 304 stainless steel using nanosecond laser. Surface modifications are tuned by adjusting laser parameters of scanning speed, repetition rate, and pulse width. A comprehensive study of the physical mechanism leading to the appearance is presented. Microscopic patterns are measured and employed as input to simulate light-matter interferences, while chemical states and crystal structures of composites to figure out intrinsic colors. Quantitative analysis clarifies the final colors and RGB values are the combinations of structural colors and intrinsic colors from the oxidized pigments, with the latter dominating. Therefore, the engineering and scientific insights of nanosecond laser coloration highlight large-scale utilization of the present route for colorful and resistant steels.

Signs of depth-luminance covariance in 3-D cluttered scenes.

PubMed

Scaccia, Milena; Langer, Michael S

2018-03-01

In three-dimensional (3-D) cluttered scenes such as foliage, deeper surfaces often are more shadowed and hence darker, and so depth and luminance often have negative covariance. We examined whether the sign of depth-luminance covariance plays a role in depth perception in 3-D clutter. We compared scenes rendered with negative and positive depth-luminance covariance where positive covariance means that deeper surfaces are brighter and negative covariance means deeper surfaces are darker. For each scene, the sign of the depth-luminance covariance was given by occlusion cues. We tested whether subjects could use this sign information to judge the depth order of two target surfaces embedded in 3-D clutter. The clutter consisted of distractor surfaces that were randomly distributed in a 3-D volume. We tested three independent variables: the sign of the depth-luminance covariance, the colors of the targets and distractors, and the background luminance. An analysis of variance showed two main effects: Subjects performed better when the deeper surfaces were darker and when the color of the target surfaces was the same as the color of the distractors. There was also a strong interaction: Subjects performed better under a negative depth-luminance covariance condition when targets and distractors had different colors than when they had the same color. Our results are consistent with a "dark means deep" rule, but the use of this rule depends on the similarity between the color of the targets and color of the 3-D clutter.

Hints at Ceres Composition from Color

NASA Image and Video Library

2015-09-30

This map-projected view of Ceres was created from images taken by NASA's Dawn spacecraft during its high-altitude mapping orbit, in August and September, 2015. Images taken using infrared (920 nanometers), red (750 nanometers) and blue (440 nanometers) spectral filters were combined to create this false-color view. Redder colors indicate places on Ceres' surface that reflect light strongly in the infrared, while bluish colors indicate enhanced reflectivity at short (bluer) wavelengths; green indicates places where albedo, or overall brightness, is strongly enhanced. Scientists use this technique in order to highlight subtle color differences across Ceres, which would appear fairly uniform in natural color. This can provide valuable insights into the mineral composition of the surface, as well as the relative ages of surface features. http://photojournal.jpl.nasa.gov/catalog/PIA19977

Short-term memory affects color perception in context.

PubMed

Olkkonen, Maria; Allred, Sarah R

2014-01-01

Color-based object selection - for instance, looking for ripe tomatoes in the market - places demands on both perceptual and memory processes: it is necessary to form a stable perceptual estimate of surface color from a variable visual signal, as well as to retain multiple perceptual estimates in memory while comparing objects. Nevertheless, perceptual and memory processes in the color domain are generally studied in separate research programs with the assumption that they are independent. Here, we demonstrate a strong failure of independence between color perception and memory: the effect of context on color appearance is substantially weakened by a short retention interval between a reference and test stimulus. This somewhat counterintuitive result is consistent with Bayesian estimation: as the precision of the representation of the reference surface and its context decays in memory, prior information gains more weight, causing the retained percepts to be drawn toward prior information about surface and context color. This interaction implies that to fully understand information processing in real-world color tasks, perception and memory need to be considered jointly.

Color stability of different denture teeth materials: an in vitro study.

PubMed

Mutlu-Sagesen, L; Ergün, G; Ozkan, Y; Bek, B

2001-09-01

The aim of this in vitro study was to compare the color stability of commercially available porcelain, reinforced acrylic, and conventional acrylic denture teeth materials used in removable prostheses. Two brands of porcelain (Unilux-Enta Lactona-Holland and Vivoperl-Ivoclar-Liechtenstein), 2 brands of reinforced acrylic (Optodent-Bayer-Germany and Ivolek-Ivoclar-Liechtenstein), and 2 brands of conventional acrylic (Isodent-Güney Diş Deposu-Turkey and Samed-Turkey), were made, for a total of 6 different denture teeth groups. Denture teeth were subjected to 3 staining solutions (filtered coffee, tea, and cola) and distilled water. From each group of denture teeth, 4 sets of maxillary anterior denture teeth were immersed in each of the 4 solutions. The color values of denture teeth were measured colorimetrically with the Gardner XL 20 Tristimulus Colorimeter (Gardner Lab. Inc., Bethesda, Maryland, USA). Color changes were characterized in the CIEL*a*b* color space. Color change values were determined after 1 day, 1 week, 2 weeks, and 4 weeks. The color difference values were calculated and then evaluated by two-way ANOVA statistically. The filtered coffee solution was found to be more chromogenic than the other 2 staining solutions, while porcelain denture teeth materials were more color stable. Assuming the color change of deltaE* < 1.0 as a discernible limit and deltaE* = 3.3 as an acceptable value, the filtered coffee, tea, and cola had slight staining effects on all 6 groups of denture teeth.

Serial-to-parallel color-TV converter

NASA Technical Reports Server (NTRS)

Doak, T. W.; Merwin, R. B.; Zuckswert, S. E.; Sepper, W.

1976-01-01

Solid analog-to-digital converter eliminates flicker and problems with time base stability and gain variation in sequential color TV cameras. Device includes 3-bit delta modulator; two-field memory; timing, switching, and sync network; and three 3-bit delta demodulators

Parallel detection of violations of color constancy

PubMed Central

Foster, David H.; Nascimento, Sérgio M. C.; Amano, Kinjiro; Arend, Larry; Linnell, Karina J.; Nieves, Juan Luis; Plet, Sabrina; Foster, Jeffrey S.

2001-01-01

The perceived colors of reflecting surfaces generally remain stable despite changes in the spectrum of the illuminating light. This color constancy can be measured operationally by asking observers to distinguish illuminant changes on a scene from changes in the reflecting properties of the surfaces comprising it. It is shown here that during fast illuminant changes, simultaneous changes in spectral reflectance of one or more surfaces in an array of other surfaces can be readily detected almost independent of the numbers of surfaces, suggesting a preattentive, spatially parallel process. This process, which is perfect over a spatial window delimited by the anatomical fovea, may form an early input to a multistage analysis of surface color, providing the visual system with information about a rapidly changing world in advance of the generation of a more elaborate and stable perceptual representation. PMID:11438751

The correlation between radiative surface defect states and high color rendering index from ZnO nanotubes

PubMed Central

2011-01-01

Combined surface, structural and opto-electrical investigations are drawn from the chemically fashioned ZnO nanotubes and its heterostructure with p-GaN film. A strong correlation has been found between the formation of radiative surface defect states in the nanotubes and the pure cool white light possessing averaged eight color rendering index value of 96 with appropriate color temperature. Highly important deep-red color index value has been realized > 95 which has the capability to render and reproduce natural and vivid colors accurately. Diverse types of deep defect states and their relative contribution to the corresponding wavelengths in the broad emission band is suggested. PMID:21878100

Effect of surface treatments and coffee thermocycling on the color and translucency of CAD-CAM monolithic glass-ceramic.

PubMed

Alp, Gulce; Subasi, Meryem Gulce; Johnston, William M; Yilmaz, Burak

2018-03-15

The effects of surface treatments and coffee thermocycling on the color and relative translucency of a recently introduced computer-aided design and computer-aided manufacturing (CAD-CAM) monolithic glass-ceramic are unknown. The purpose of this in vitro study was to evaluate the effect of coffee thermocycling on the color and relative translucency parameter (RTP) of CAD-CAM monolithic glass-ceramics after different surface treatments. Specimens (1.5-mm-thick) were sectioned from zirconia-reinforced lithium silicate glass-ceramic (ZLS) (n=18) and lithium disilicate glass-ceramic (LDS) blocks (n=18). Two different types of surface treatments (glazing or polishing) were applied to the specimens. The specimens were subjected to 5000 thermocycles in a coffee solution. The color coordinates of specimens were measured before and after coffee thermocycling by using a spectroradiometer, and color differences and relative translucency values were calculated by using CIEDE2000 color difference and RTP formulas. ANOVA was used to analyze the color difference and relative translucency values by using maximum likelihood estimation and the Satterthwaite degrees of freedom methods. Any significant interaction between surface subgroups was further analyzed by using the Tukey-Kramer adjustment (α=.05). Material type had a significant effect on color difference (P=.018). All color difference values of all materials were smaller than the clinical acceptability threshold (<1.8 units). For relative translucency, material (P<.001) and coffee thermocycling had a significant effect (P=.014), and an interaction was found between the surface treatments and materials (P<.001). The Tukey-Kramer test revealed significant differences between glazed and polished subgroups of LDS material, except for ZLS-glazed and ZLS-polished subgroups. Different surface treatments of CAD-CAM monolithic zirconia-reinforced lithium silicate and lithium disilicate glass-ceramics resulted in clinically acceptable color changes after coffee thermocycling. The color changes in all groups, except for LDS-polished, were not perceivable. Lithium disilicate was more translucent than zirconia-reinforced lithium silicate before and after coffee thermocycling. Coffee thermocycling decreased the translucency of both of the materials. Different surface treatments affected the translucency of only lithium disilicate for tested thickness. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

A color management system for multi-colored LED lighting

NASA Astrophysics Data System (ADS)

Chakrabarti, Maumita; Thorseth, Anders; Jepsen, Jørgen; Corell, Dennis D.; Dam-Hansen, Carsten

2015-09-01

A new color control system is described and implemented for a five-color LED light engine, covering a wide white gamut. The system combines a new way of using pre-calibrated lookup tables and a rule-based optimization of chromaticity distance from the Planckian locus with a calibrated color sensor. The color sensor monitors the chromaticity of the mixed light providing the correction factor for the current driver by using the generated lookup table. The long term stability and accuracy of the system will be experimentally investigated with target tolerance within a circle radius of 0.0013 in the uniform chromaticity diagram (CIE1976).

Synthesis and characterization of tetra phenoxy-substituted halogen-rich metallophthalocyanine derivatives: A study on their LCD color filter requirements

NASA Astrophysics Data System (ADS)

Muthukumar, Palanisamy; Kim, Hak-Soo; Jeong, Jong Woo; Son, Young-A.

2016-09-01

This study addresses the synthesis and characterization of new tetra phenoxy-substituted halogen-rich metallophthalocyanine derivatives (MPcs) 4-7 (M = Co, Ni, Cu and Zn). The synthesized new compounds were characterized using UV-Vis, FT-IR, MALDI-TOF, 1H NMR and elemental analyses. In addition, the basic requirements such as aggregation behavior, thermal stability, transmittance and solubility in propylene glycol monomethyl ether acetate (PGMEA) of MPcs 4-7 were investigated for their usage as a green color filter in Liquid Crystal Displays (LCDs). All of the MPcs showed thermal stability and sufficient solubility in PGMEA. However, the addition of binder into PGMEA solution of MPcs 5 and 6 leads to precipitation. Among the four MPcs, zinc phthalocyanine (7) showed higher transmittance. The higher transmittance of zinc phthalocyanine (7) along with its thermal stability and sufficient solubility in PGMEA are promising for its application as a green color filter in LCDs.

A model of color vision with a robot system

NASA Astrophysics Data System (ADS)

Wang, Haihui

2006-01-01

In this paper, we propose to generalize the saccade target method and state that perceptual stability in general arises by learning the effects one's actions have on sensor responses. The apparent visual stability of color percept across saccadic eye movements can be explained by positing that perception involves observing how sensory input changes in response to motor activities. The changes related to self-motion can be learned, and once learned, used to form stable percepts. The variation of sensor data in response to a motor act is therefore a requirement for stable perception rather than something that has to be compensated for in order to perceive a stable world. In this paper, we have provided a simple implementation of this sensory-motor contingency view of perceptual stability. We showed how a straightforward application of the temporal difference enhancement learning technique yielding color percepts that are stable across saccadic eye movements, even though the raw sensor input may change radically.

Stabilization of anthocyanins in blackberry juice by glutathione fortification.

PubMed

Stebbins, Nathan B; Howard, Luke R; Prior, Ronald L; Brownmiller, Cindi; Mauromoustakos, Andy

2017-10-18

Blackberry anthocyanins provide attractive color and antioxidant activity. However, anthocyanins degrade during juice processing and storage, so maintaining high anthocyanin concentrations in berry juices may lead to greater antioxidant and health benefits for the consumer. This study evaluated potential additives to stabilize anthocyanins during blackberry juice storage. The anthocyanin stabilizing agents used were: glutathione, galacturonic acid, diethylenetriaminepentaacetic acid and tannic acid, which were added at a level of 500 mg L -1 . Juice anthocyanin, flavonol, and ellagitannin content and percent polymeric color were measured over five weeks of accelerated storage at 30 °C. Glutathione had the greatest protective effect on total anthocyanins and polymeric color. Therefore a second study was performed with glutathione in combination with lipoic and ascorbic acids in an effort to use antioxidant recycling to achieve a synergistic effect. However, the antioxidant recycling system had no protective effect relative to glutathione alone. Glutathione appears to be a promising blackberry juice additive to protect against anthocyanin degradation during storage.

The Color of Pluto from New Horizons

NASA Astrophysics Data System (ADS)

Olkin, Catherine; Spencer, John R.; Grundy, William M.; Parker, Alex; Beyer, Ross A.; Reuter, Dennis; Schenk, Paul M.; Stern, S. Alan; Weaver, Harold A.; Young, Leslie; Ennico, Kimberly; Binzel, Richard P.; Buie, Marc W.; Cook, Jason C.; Cruikshank, Dale P.; Dalle Ore, Cristina M.; Earle, Alissa; Howett, Carly; Jennings, Donald E.; Singer, Kelsi N.; Linscott, Ivan; Lunsford, Allen; Protopapa, Silvia; Schmitt, Bernard; Weigle, Eddie; and the New Horizons Science Team

2017-10-01

The New Horizons flyby provided the first high-resolution color maps of Pluto. These maps show the color variegation across the surface from the very red terrain in the equatorial region, to the more neutral colors of the volatile ices in Sputnik Planitia, the blue terrain of east Tombaugh Regio and the yellow hue on Pluto's north pole. There are two distinct color mixing lines in the color-color diagrams derived from images of Pluto. Both mixing lines have an apparent starting point in common: the relatively neutral color volatile-ice covered terrain. One line extends to the dark red terrain exemplified by Cthulu Regio and the other extends to the yellow hue in the northern latitudes. The red color is consistent with a non-ice component on the surface and is consistent with tholins.

The Color of Pluto from New Horizons

NASA Astrophysics Data System (ADS)

Olkin, C.; Spencer, J. R.; Grundy, W. M.; Parker, A. H.; Beyer, R. A.; Reuter, D.; Schenk, P.; Stern, A.; Weaver, H. A., Jr.; Young, L. A.; Ennico Smith, K.

2017-12-01

The New Horizons flyby provided the first high-resolution color maps of Pluto. These maps show the color variegation across the surface from the very red terrain in the equatorial region, to the more neutral colors of the volatile ices in Sputnik Planitia, the blue terrain of east Tombaugh Regio and the yellow hue on Pluto's north pole. There are two distinct color mixing lines in the color-color diagrams derived from images of Pluto. Both mixing lines have an apparent starting point in common: the relatively neutral color volatile-ice covered terrain. One line extends to the dark red terrain exemplified by Cthulu Regio and the other extends to the yellow hue in the northern latitudes. The red color is consistent with a non-ice component on the surface and is consistent with tholins.

The Colors of Tethys I

NASA Image and Video Library

2015-07-29

This enhanced-color mosaic of Saturn's icy moon Tethys shows a range of features on the moon's trailing hemisphere. Tethys is tidally locked to Saturn, so the trailing hemisphere is the side of the moon that always faces opposite its direction of motion as it orbits the planet. Images taken using clear, green, infrared and ultraviolet spectral filters were combined to create the view, which highlights subtle color differences across Tethys' surface at wavelengths not visible to human eyes. The moon's surface is fairly uniform in natural color. The color of the surface changes conspicuously across the disk, from yellowish hues to nearly white. These broad color changes are affected by a number of external processes. First, Saturn's diffuse E-ring preferentially bombards Tethys' leading hemisphere, toward the right side of this image, with ice bright ice grains. At the same time, charged particles from Saturn's radiation belt bombard the surface on the trailing side, causing color changes due to chemical alteration of the materials there. The albedo -- a measure of the surface's reflectivity -- drops by 10 to 15 percent from the moon's leading side to the trailing side. Similar global color patterns exist on other Saturnian moons. On a much smaller scale, enigmatic, arc-shaped, reddish streaks also are faintly visible across the heavily-cratered surface, particularly if one enhances color saturation in the image (see PIA19637 for a close-up view of these features). The origin of this localized color contrast is not yet understood. Mountains on the floor of the 280 mile- (450 kilometer-) wide Odysseus impact basin are visible at upper right, around the two o'clock position. This mosaic is an orthographic projection constructed from 52 Cassini images obtained on April 11, 2015 with the Cassini spacecraft narrow-angle camera. Resolution is about 1,000 feet (300 meters) per pixel. The images were obtained at a distance of approximately 33,000 miles (53,000 kilometers) from Tethys. http://photojournal.jpl.nasa.gov/catalog/PIA19636

Effect of genuine non-anthocyanin phenolics and chlorogenic acid on color and stability of black carrot (Daucus carota ssp. sativus var. atrorubens Alef.) anthocyanins.

PubMed

Gras, Claudia C; Bogner, Hanna; Carle, Reinhold; Schweiggert, Ralf M

2016-07-01

This work aimed at studying the color intensity and stability of black carrot anthocyanins as influenced by intermolecular co-pigmentation. For this purpose, purified anthocyanin solutions were supplemented with purified genuine black carrot phenolics, chlorogenic acid, and an aqueous phenolic-rich green coffee bean extract at various anthocyanin:co-pigment ratios (1:0-1:162; pH 3.6). The hyperchromic co-pigmentation effect depended on the concentration of added co-pigments, resulting in an absorbance increase of up to 22% at the absorption maximum. Anthocyanin stability during heating (90°C, 5h) was barely improved unless the concentrations of co-pigments exceeded those of their natural source. When adding co-pigments at ratios above 1:9.4, anthocyanin heat stability was significantly improved. As acylated anthocyanins were most stable, breeders might aim at increasing their content in the future, while breeding for high levels of colorless polyphenols may be unreachable. Nevertheless, we provided proof-of-concept for the successful color enhancement by the addition of a phenolic-rich green coffee bean extract, being useful for food-grade applications. Copyright © 2016 Elsevier Ltd. All rights reserved.

Influence of nanoparticles on color stability, microhardness, and flexural strength of acrylic resins specific for ocular prosthesis.

PubMed

Andreotti, Agda Marobo; Goiato, Marcelo Coelho; Moreno, Amália; Nobrega, Adhara Smith; Pesqueira, Aldiéris Alves; dos Santos, Daniela Micheline

2014-01-01

The aim of this study was to assess the effect of adding nanoparticles to N1 acrylic resin intended for artificial sclera, in terms of the color stability, microhardness, and flexural strength of the resin. Three hundred samples of N1 acrylic resin were used: 100 samples for color stability and microhardness tests (each test was performed on the opposite side of each sample), and 200 samples for flexural strength testing (100 samples before and after 1,008 hours of accelerated aging). Samples for each test were separated into ten groups (n=10), ie, without nanoparticles (control group) or with nanoparticles of zinc oxide, titanium dioxide (TiO₂), and barium sulfate at weight concentrations of 1%, 2%, and 2.5% (nanoparticle groups). Data were subjected to statistical analysis with nested analysis of variance and Tukey's test (P<0.05 significance level). Among the nanoparticle groups, the TiO₂ groups showed better color stability at all concentrations. Microhardness values increased after artificial aging, except for the control and zinc oxide groups. After aging, the 1%-2% TiO₂ groups had significantly higher microhardness values compared with the other nanoparticle groups. Before aging, there was a significant difference in flexural strength between the control and nanoparticle groups. After aging, the control and TiO₂ groups, regardless of concentration, showed the lowest flexural strength values. Incorporation of nanoparticles directly influenced the acrylic resin properties, with TiO₂ being the most influential nanoparticle in terms of the evaluated properties.

Martian soil stratigraphy and rock coatings observed in color-enhanced Viking Lander images

NASA Technical Reports Server (NTRS)

Strickland, E. L., III

1979-01-01

Subtle color variations of martian surface materials were enhanced in eight Viking Lander (VL) color images. Well-defined soil units recognized at each site (six at VL-1 and four at VL-2), are identified on the basis of color, texture, morphology, and contact relations. The soil units at the Viking 2 site form a well-defined stratigraphic sequence, whereas the sequence at the Viking 1 site is only partially defined. The same relative soil colors occur at the two sites, suggesting that similar soil units are widespread on Mars. Several types of rock surface materials can be recognized at the two sites; dark, relatively 'blue' rock surfaces are probably minimally weathered igneous rock, whereas bright rock surfaces, with a green/(blue + red) ratio higher than that of any other surface material, are interpreted as a weathering product formed in situ on the rock. These rock surface types are common at both sites. Soil adhering to rocks is common at VL-2, but rare at VL-1. The mechanism that produces the weathering coating on rocks probably operates planet-wide.

Formation and transformation of the radiation-induced nearsurface color centers in sodium and lithium fluorides nanocrystals

NASA Astrophysics Data System (ADS)

Novikov, A. N.; Kalinov, V. S.; Radkevich, A. V.; Runets, L. P.; Stupak, A. P.; Voitovich, A. P.

2017-11-01

Near-surface color centers in sodium fluoride nanocrystals have been formed. At pre-irradiation annealing of sodium and lithium fluorides samples at temperatures of 623 K and above, the near-surface color centers in them have not been found after γ-irradiation. Annealing lithium fluoride nanocrystals with the near-surface defects leads to their transformation into bulk ones of the same composition.

Randomized clinical study of alterations in the color and surface roughness of dental enamel brushed with whitening toothpaste.

PubMed

de Moraes Rego Roselino, Lourenço; Tirapelli, Camila; de Carvalho Panzeri Pires-de-Souza, Fernanda

2018-03-30

This clinical study evaluated the influence of whitening toothpaste on color and surface roughness of dental enamel. Initially, the abrasiveness of the toothpastes used (Sorriso Dentes Brancos [SDB]; Colgate Luminous White and Close up White Now) was tested on 30 (n = 10) plexiglass acrylic plates that were submitted to mechanical tooth brushing totalizing 29,200 cycles. Subsequently, 30 participants were selected, and received a toothbrush and nonwhitening toothpaste (SDB). The participants used these products for 7 days and initial color readouts (Spectrophotometer) and surface roughness of one maxillary central incisors was performed after this period of time. For surface roughness readouts, one replica of the maxillary central incisor was obtained by a polyvinyl siloxane impression material (Express) and polyurethane resin. After baseline measurements, participants were separated into three groups (n = 10), according to the toothpaste used. The participants returned after 7, 30, and 90 days when new color readouts and surface roughness were recorded. The measured values were statistically analyzed (2-way-ANOVA, repeated measures, Tukey, P < .05). Whitening toothpastes did not promote significant (P > .05) color alteration and nor increased the surface roughness of the dental enamel in brushing time of the study. The abrasiveness of whitening toothpaste and the brushing trial period did not affect the surface roughness of dental enamel. However, color changes observed on enamel were above the perceptibility and acceptability thresholds reported in the literature. The over-the-counter toothpastes tested had an effect on dental enamel color above the perceptibility and acceptability thresholds but did not change the surface roughness of the teeth. © 2018 Wiley Periodicals, Inc.

Compositional and Mechanical Properties of Peanuts Roasted to Equivalent Colors using Different Time/Temperature Combinations

USDA-ARS?s Scientific Manuscript database

Peanuts in North America and Europe are primarily consumed after dry roasting. Standard industry practice is to roast peanuts to a specific surface color (Hunter L-value) for a given application; however, equivalent surface colors can be attained using different roast temperature/time combinations,...

Naked-eye point-of-care testing platform based on a pH-responsive superwetting surface: toward the non-invasive detection of glucose

NASA Astrophysics Data System (ADS)

Gao, Zhong Feng; Sann, Ei Ei; Lou, Xiaoding; Liu, Renyi; Dai, Jun; Zuo, Xiaolei; Xia, Fan; Jiang, Lei

2018-04-01

Herein, we demonstrate a contact angle (CA)-based naked-eye point-of-care testing platform with rapid pH-responsive superwettability that can switch between superhydrophilic and superhydrophobic properties for quantitative biosensing. The CA of the droplet on the pH-responsive surface approached 0° at pH 1 and conversely reached 161.4° ± 6.2° at pH 13. We realized the sensitive detection of the pH, urea, and glucose by monitoring the changes in the CA. The traditional invasive diagnosis of diabetes causes pain and brings the risk of infections, such as acquired immune deficiency syndrome (AIDS), hepatitis B, hepatitis C, and syphilis, to the user. To address this issue, we implemented a method for the non-invasive diagnosis of diabetes in human saliva and urine, which avoided the significant drawbacks mentioned above. The accuracy of this method was demonstrated by comparing the results with those from commercial glucometers and theoretical calculations. Interestingly, we successfully monitored glucose levels in sweat before, during, and after cycling. The sensing performance was barely influenced by the temperature, elevation, and droplet color, illustrating promise for expansion to hundreds of millions of potential customers, especially those with color blindness or color weakness. Given its low cost, lack of instruments, and rapid response (within 1 s), this strategy might overcome the limitations of the mechanical stability and durability of superwettable materials and thus might extend the industrial-scale application of bioinspired superwettable systems.

Surface functionalization of polyamide fiber via dopamine polymerization

NASA Astrophysics Data System (ADS)

Kuang, Xiao-Hui; Guan, Jin-Ping; Tang, Ren-Cheng; Chen, Guo-Qiang

2017-09-01

The oxidative polymerization of dopamine for the functional surface modification of textile fibers has drawn great attention. In this work, the functionalization of polyamide fiber via dopamine polymerization was studied with the aim of the fabrication of hydrophilic and antistatic surface. The conditions of dopamine application were first discussed in the absence of specific oxidants in terms of the apparent color depth of polyamide fiber. Dopamine concentration, pH and time were found to exert great impact on color depth. The highest color depth was achieved at pH 8.5. In the process of modification, polydopamine was deposited onto the surface of polyamide fiber. The modified polyamide fiber displayed a yellowish brown color with excellent wash and light color fastness, and exhibited good hydrophilic, UV protection and antistatic effects. A disadvantage of the present approach was the slow rate of dopamine polymerization and functionalization.

Moment Lyapunov Exponent and Stochastic Stability of Binary Airfoil under Combined Harmonic and Non-Gaussian Colored Noise Excitations

NASA Astrophysics Data System (ADS)

Hu, D. L.; Liu, X. B.

Both periodic loading and random forces commonly co-exist in real engineering applications. However, the dynamic behavior, especially dynamic stability of systems under parametric periodic and random excitations has been reported little in the literature. In this study, the moment Lyapunov exponent and stochastic stability of binary airfoil under combined harmonic and non-Gaussian colored noise excitations are investigated. The noise is simplified to an Ornstein-Uhlenbeck process by applying the path-integral method. Via the singular perturbation method, the second-order expansions of the moment Lyapunov exponent are obtained, which agree well with the results obtained by the Monte Carlo simulation. Finally, the effects of the noise and parametric resonance (such as subharmonic resonance and combination additive resonance) on the stochastic stability of the binary airfoil system are discussed.

Zonally averaged thermal balance and stability models for nitrogen polar caps on Triton

NASA Technical Reports Server (NTRS)

Stansberry, John A.; Lunine, J. I.; Porco, C. C.; Mcewen, A. S.

1990-01-01

Voyager four-color imaging data of Triton are analyzed to calculate the bolometric hemispheric albedo as a function of latitude and longitude. Zonal averages of these data have been incorporated into a thermal balance model involving insolation, reradiation, and latent heat of sublimation of N2 ice for the surface. The current average bolometric albedo of Triton's polar caps is 0.8, implying an effective temperature of 34.2 K and a surface pressure of N2 of 1.6 microbar for unit emissivity. This pressure is an order of magnitude lower than the surface pressure of 18 microbar inferred from Voyager data (Broadfoot et al., 1989; Conrath et al., 1989), a discrepancy that can be reconciled if the emissivity of the N2 on Triton's surface is 0.66. The model predicts that Triton's surface north of 15 deg N latitude is experiencing deposition of N2 frosts, as are the bright portions of the south polar cap near the equator. This result explains why the south cap covers nearly the entire southern hemisphere of Triton.

Visual Determination of Industrial Color-Difference Tolerances Using Probit Analysis

DTIC Science & Technology

1991-06-01

determine the median tolerance values of 45 color-difference vectors in CIELAB color space using surface mode viewing of paint samples. Nine different...8 4. Distribution Design for Color Centers in CIELAB Color Space ............................. 13 5. CIE Recommended Color Centers...compared to a near neutral anchor color- difference stimulus. The experiment concentrated on nine color centers systematically distributed in CIELAB color

High-efficiency/CRI/color stability warm white organic light-emitting diodes by incorporating ultrathin phosphorescence layers in a blue fluorescence layer

NASA Astrophysics Data System (ADS)

Miao, Yanqin; Wang, Kexiang; Zhao, Bo; Gao, Long; Tao, Peng; Liu, Xuguang; Hao, Yuying; Wang, Hua; Xu, Bingshe; Zhu, Furong

2018-01-01

By incorporating ultrathin (<0.1 nm) green, yellow, and red phosphorescence layers with different sequence arrangements in a blue fluorescence layer, four unique and simplified fluorescence/phosphorescence (F/P) hybrid, white organic light-emitting diodes (WOLEDs) were obtained. All four devices realize good warm white light emission, with high color rending index (CRI) of >80, low correlated color temperature of <3600 K, and high color stability at a wide voltage range of 5 V-9 V. These hybrid WOLEDs also reveal high forward-viewing external quantum efficiencies (EQE) of 17.82%-19.34%, which are close to the theoretical value of 20%, indicating an almost complete exciton harvesting. In addition, the electroluminescence spectra of the hybrid WOLEDs can be easily improved by only changing the incorporating sequence of the ultrathin phosphorescence layers without device efficiency loss. For example, the hybrid WOLED with an incorporation sequence of ultrathin red/yellow/green phosphorescence layers exhibits an ultra-high CRI of 96 and a high EQE of 19.34%. To the best of our knowledge, this is the first WOLED with good tradeoff among device efficiency, CRI, and color stability. The introduction of ultrathin (<0.1 nm) phosphorescence layers can also greatly reduce the consumption of phosphorescent emitters as well as simplify device structures and fabrication process, thus leading to low cost. Such a finding is very meaningful for the potential commercialization of hybrid WOLEDs.

Color Stability of New Esthetic Restorative Materials: A Spectrophotometric Analysis

PubMed Central

Vialba, Lodovico; Federico, Ricaldone; Colombo, Marco; Beltrami, Riccardo

2017-01-01

The aim of this in vitro study was to evaluate and compare the color stability of different esthetic restorative materials (one microfilled composite, one nanofilled composite, one nanoceramic composite, one microfilled hybrid composite, one microfilled hybrid composite, one nanohybrid Ormocer based composite and one supra-nano spherical hybrid composite) after exposure to different staining solutions (physiological saline, red wine, coffee). All materials were prepared and polymerized into silicon rings (2 mm × 6 mm × 8 mm) to obtain specimens identical in size. Thirty cylindrical specimens of each material were prepared. Specimens were immersed in staining solutions (physiological saline, coffee and red wine) over a 28-day test period. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. The Shapiro–Wilk test and ANOVA were applied to assess significant differences among restorative materials. A paired t-test was applied to test which CIE L*a*b* parameters significantly changed after immersion in staining solutions. All restorative materials showed significant color differences after immersion in coffee. Coffee caused a significant color change in all types of tested composite resins. Only Filtek Supreme XTE demonstrated a staining susceptibility to red wine; no other significant differences among the materials were demonstrated. Long-term exposure to some food dyes (coffee in particular) can significantly affect the color stability of modern esthetic restorative materials regardless of materials’ different compositions. PMID:28684672

The effect of solvents on the stabilities (color and Fe) of anthocyanin isolated from the red-color-melinjo peels

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tarmizi, Ermiziar, E-mail: uph-ermi@yahoo.com, E-mail: ermitarmizi@gmail.com; Saragih, Raskita, E-mail: raskitasaragih@yahoo.com; Lalasari, Latifa Hanum, E-mail: ifa-sari@yahoo.com, E-mail: lati003@lipi.go.id

Anthocyanin from the red-color-melinjo peels could be isolated using a polar solvent (ethanol) [ermiziar, 2010]. The amount of hydrocarbons in the structure of anthocyanin might cause that anthocyanin could be isolated using a non polar solvent. The purpose of research is to isolate anthocyanin using non polar solvents (hexane and petroleum ether) with maceration steps for 24 hours and separate solvents using rotary evaporator equipment. The stability of anthocyanin could be observed every week (1,2,3 and 4 weeks) in various environmental conditions (with or without light in refrigerator and open or closed storage). The characterization of anthocyanin was analyzed withmore » visual (physic photo) and or using equipments such as Fourier Transform Infrared Spectroscopy (FTIR) for determining functional groups, Ultraviolet–Visible Spectroscopy (UV/Vis) with 500-550 nm wavelengths for deciding absorption of anthocyanin and atomic absorption spectroscopy (AAS) for analyzing Fe element. The result showed that anthocyanin isolation with hexane solvent has yield higher than petroleum eter solvent. From the results of physic observation for 4 weeks looked that there are changing colors of samples significant after 3 and 4 weeks in cooler with or without light. The stability of anthocyanin color was the best on the storage time until 2 weeks using hexane solvent in refrigerator and closed condition that it has absorption of 0.6740 with 500 nm wavelengths and Fe concentration 6.29 ppm.« less

Color Stability of New Esthetic Restorative Materials: A Spectrophotometric Analysis.

PubMed

Poggio, Claudio; Vialba, Lodovico; Berardengo, Anna; Federico, Ricaldone; Colombo, Marco; Beltrami, Riccardo; Scribante, Andrea

2017-07-06

The aim of this in vitro study was to evaluate and compare the color stability of different esthetic restorative materials (one microfilled composite, one nanofilled composite, one nanoceramic composite, one microfilled hybrid composite, one microfilled hybrid composite, one nanohybrid Ormocer based composite and one supra-nano spherical hybrid composite) after exposure to different staining solutions (physiological saline, red wine, coffee). All materials were prepared and polymerized into silicon rings (2 mm × 6 mm × 8 mm) to obtain specimens identical in size. Thirty cylindrical specimens of each material were prepared. Specimens were immersed in staining solutions (physiological saline, coffee and red wine) over a 28-day test period. A colorimetric evaluation according to the CIE L*a*b* system was performed by a blind trained operator at 7, 14, 21, 28 days of the staining process. The Shapiro-Wilk test and ANOVA were applied to assess significant differences among restorative materials. A paired t -test was applied to test which CIE L*a*b* parameters significantly changed after immersion in staining solutions. All restorative materials showed significant color differences after immersion in coffee. Coffee caused a significant color change in all types of tested composite resins. Only Filtek Supreme XTE demonstrated a staining susceptibility to red wine; no other significant differences among the materials were demonstrated. Long-term exposure to some food dyes (coffee in particular) can significantly affect the color stability of modern esthetic restorative materials regardless of materials' different compositions.

Step-wise addition of disulfide bridge in firefly luciferase controls color shift through a flexible loop: a thermodynamic perspective.

PubMed

Nazari, Mahboobeh; Hosseinkhani, Saman; Hassani, Leila

2013-02-01

Multi-color bioluminescence is developed using the introduction of single/double disulfide bridges in firefly luciferase. The bioluminescence reaction, which uses luciferin, Mg(2+)-ATP and molecular oxygen to yield an electronically excited oxyluciferin, is carried out by the luciferase and emits visible light. The bioluminescence color of firefly luciferases is determined by the luciferase sequence and assay conditions. It has been proposed that the stability of a protein may increase through the introduction of a disulfide bridge that decreases the configurational entropy of unfolding. Single and double disulfide bridges are introduced into Photinus pyralis firefly luciferase to make separate mutant enzymes with a single/double bridge (C(81)-A(105)C, L(306)C-L(309)C, P(451)C-V(469)C; C(81)-A(105)C/P(451)C-V(469)C, and A(296)C-A(326)C/P(451)C-V(469)C). By introduction of disulfide bridges using site-directed mutagenesis in Photinus pyralis luciferase the color of emitted light was changed to red or kept in different extents. The bioluminescence color shift occurred with displacement of a critical loop in the luciferase structure without any change in green emitter mutants. Thermodynamic analysis revealed that among mutants, L(306)C-L(309)C shows a remarkable stability against urea denaturation and also a considerable increase in kinetic stability and a clear shift in bioluminescence spectra towards red.

Plasmonic- and dielectric-based structural coloring: from fundamentals to practical applications

NASA Astrophysics Data System (ADS)

Lee, Taejun; Jang, Jaehyuck; Jeong, Heonyeong; Rho, Junsuk

2018-01-01

Structural coloring is production of color by surfaces that have microstructure fine enough to interfere with visible light; this phenomenon provides a novel paradigm for color printing. Plasmonic color is an emergent property of the interaction between light and metallic surfaces. This phenomenon can surpass the diffraction limit and achieve near unlimited lifetime. We categorize plasmonic color filters according to their designs (hole, rod, metal-insulator-metal, grating), and also describe structures supported by Mie resonance. We discuss the principles, and the merits and demerits of each color filter. We also discuss a new concept of color filters with tunability and reconfigurability, which enable printing of structural color to yield dynamic coloring at will. Approaches for dynamic coloring are classified as liquid crystal, chemical transition and mechanical deformation. At the end of review, we highlight a scale-up of fabrication methods, including nanoimprinting, self-assembly and laser-induced process that may enable real-world application of structural coloring.

Using antibrowning agents to enhance quality and safety of fresh-cut avocado treated with intense light pulses.

PubMed

Ramos-Villarroel, Ana Y; Martín-Belloso, Olga; Soliva-Fortuny, Robert

2011-01-01

The effect of antibrowning compounds on the color and firmness of fresh-cut avocado treated with intense light pulses (ILP), as well as their impact on the survival of Listeria innocua, was investigated in this study. Dipping solutions containing 2% (w/v) L-cysteine without ascorbic acid and combined with 1% (w/v) citric acid and 1% w/v calcium lactate most effectively preserved the initial color and texture of ILP-treated fresh-cut avocado. On the other hand, ILP treatments caused a reduction of more than 3 log cycles in the populations of L. innocua inoculated on fresh-cut avocado. Log reduction levels increased when antibrowning agents were combined with ILP treatments. In conclusion, the use of quality-stabilizing agents is a good option to guarantee both the microbiological safety of fresh-cut avocado treated with ILP as well as to improve its physical and chemical quality. Intense light pulses (ILP) have received considerable attention during the last years after its approval by the U.S. Food and Drug Administration (FDA) in 1996 as a decontamination method for food or food surfaces. This article presents relevant information regarding the effect of ILP treatments combined with quality-stabilizing compounds as a feasible alternative to improve the physical and chemical quality of fresh-cut avocado as well as to guarantee its microbiological safety. © 2011 Institute of Food Technologists®

Efficient color display using low-absorption in-pixel color filters

NASA Technical Reports Server (NTRS)

Wang, Yu (Inventor)

2000-01-01

A display system having a non-absorbing and reflective color filtering array and a reflector to improve light utilization efficiency. One implementation of the color filtering array uses a surface plasmon filter having two symmetric metal-dielectric interfaces coupled with each other to produce a transmission optical wave at a surface plasmon resonance wavelength at one interface from a p-polarized input beam on the other interface. Another implementation of the color filtering array uses a metal-film interference filter having two dielectric layers and three metallic films.

Method for determining shear direction using liquid crystal coatings

NASA Technical Reports Server (NTRS)

Reda, Daniel C.

1995-01-01

A method is provided for determining shear direction wherein a beam of white light is directed onto the surface of a liquid crystal coating to cause the white light to be dispersed (reflected) from the surface in a spectrum having bands of different colors in a fixed spatial 2 (angular) sequence. The system is calibrated by locating an observer, e.g., a video and movie camera, such that a particular color band (preferably at or near the center of the reflected spectrum) is observed to thereby provide a reference color band. Because the application of shear causes either clockwise or counterclockwise rotation of the reflected spectrum dependent on the direction of the shear, a determination is then made of the reflected color band observed by the observer when the surface of the liquid crystal is subjected to shear to thereby determine the direction of the shear based on the directional (rotation) relation of the observed color band with respect to the reference color band in the spatial sequence of color bands.

Short-Term Memory Affects Color Perception in Context

PubMed Central

Olkkonen, Maria; Allred, Sarah R.

2014-01-01

Color-based object selection — for instance, looking for ripe tomatoes in the market — places demands on both perceptual and memory processes: it is necessary to form a stable perceptual estimate of surface color from a variable visual signal, as well as to retain multiple perceptual estimates in memory while comparing objects. Nevertheless, perceptual and memory processes in the color domain are generally studied in separate research programs with the assumption that they are independent. Here, we demonstrate a strong failure of independence between color perception and memory: the effect of context on color appearance is substantially weakened by a short retention interval between a reference and test stimulus. This somewhat counterintuitive result is consistent with Bayesian estimation: as the precision of the representation of the reference surface and its context decays in memory, prior information gains more weight, causing the retained percepts to be drawn toward prior information about surface and context color. This interaction implies that to fully understand information processing in real-world color tasks, perception and memory need to be considered jointly. PMID:24475131

Alternating twist structures formed by electroconvection in the nematic phase of an achiral bent-core molecule.

PubMed

Tanaka, Shingo; Dhara, Surajit; Sadashiva, B K; Shimbo, Yoshio; Takanishi, Yoichi; Araoka, Fumito; Ishikawa, Ken; Takezoe, Hideo

2008-04-01

We report an unusual electroconvection in the nematic phase of a bent-core liquid crystal. In a voltage-frequency diagram, two frequency regions exhibiting prewavy stripe patterns were found, as reported by Wiant We found that these stripes never show extinction dark when cells were rotated under crossed polarizers. Based on the color interchange in between neighboring stripes by the rotation of the cells or an analyzer, twisted molecular orientation is suggested; i.e., the directors are alternately twisted from the top to the bottom surfaces with a pretilt angle in adjacent stripes, which is an analogue of the twisted (splayed) structure observed in surface-stabilized ferroelectric liquid crystal cells. The transmittance spectra calculated using the 4x4 matrix method from the model structure are consistent with the experimental observation.

Effect of two fluoride varnishes on the color stability of three resin-based restorative materials: an in vitro study.

PubMed

Tafaroji, Raha; Biria, Mina; Ameri, Farhad; Torabzadeh, Hassan; Qahari, Pasha; Akbarzadeh Baghban, Alireza

2016-11-01

The aim of the present study was to evaluate the effect of two fluoride varnishes on color stability of three resin-based restorative materials. Fifty-four discs (14.5 × 1.7 mm) were fabricated from A2 and A3 shades of a compomer (F2000), a flowable composite (Z350), and a hybrid composite (Z250), and incubated at 37°C for 48 h. Dura Shield (colored) and Fluor Protector (colorless) fluoride varnishes were applied onto the discs. The coating was cleaned using a low-speed handpiece and nylon bristle brush after 24 h of storage in distilled water. A second coating was then applied. A control group with no coating was immersed in distilled water and used. The CIE L*a*b* color scale was measured before the treatments and following each cleaning utilizing a spectrophotometer. The colored fluoride varnish exhibited the highest overall color change (∆E) after the first and the second cleaning procedures in all the materials. Among these, the greatest color change was observed in the A3 shade of F2000, followed by the A3 shade of Z-250. The ∆E was less than 3.3 in all groups, and was therefore clinically acceptable. Color changes following the application of fluoride varnishes were found to be clinically acceptable in all groups. © 2015 Wiley Publishing Asia Pty Ltd.

Estimating Advective Near-surface Currents from Ocean Color Satellite Images

DTIC Science & Technology

2015-01-01

of surface current information. The present study uses the sequential ocean color products provided by the Geostationary Ocean Color Imager (GOCI) and...on the SuomiNational Polar-Orbiting Partner- ship (S-NPP) satellite. The GOCI is the world’s first geostationary orbit satellite sensor over the...used to extract the near-surface currents by the MCC algorithm. We not only demonstrate the retrieval of currents from the geostationary satellite ocean

[The effect of firing times on the chroma of tetragonal zirconia polycrystal by adding rare-earth oxides].

PubMed

Gao, Yan; Zhang, Fu-qiang; Huang, Hui; Gui, Lin-hua

2010-10-01

The aim of this study is to evaluate whether the firing times affect the chroma of zirconia by adding rare-earth oxides. Six kinds (S1, S2, S3, S4, S5, S6) of tooth-like yttria stabilized tetragonal zirconia polycrystal (Y-TZP) were available by introducing internal colorating technology, the color were gauged with ShadeEye NCC chromatometry instrument, and one-way ANOVA was used to analysis the color of each kind of tooth-like zirconia after 1, 2, 3, 4, 5 times firing individually. After 1, 2, 3, 4, 5 times firing respectively, the chromatic aberration ranged between 0.10-1.47 merely. The luminosity of three kinds (S1, S2, S6) of tooth-like zirconia were decreased (P < 0.05), the luminosity of the other three kinds (S3, S4, S5) of tooth-like zirconia were not obviously changed (P > 0.05), as for the hue and chroma, no significant differences were found (P > 0.05). There are no significant influence on the color of tooth-like Y-TZP after 1, 2, 3, 4, 5 times firing respectively, the chroma of yttria stabilized tetragonal zirconia polycrystal by adding rare-earth oxides are with high stability.

1-butanethiol vapor sensing based on gold nanoparticle immobilized on glass slide by digital color analysis

NASA Astrophysics Data System (ADS)

Shokoufi, Nader; Adeleh, Sara

2017-12-01

We demonstrate that gold nanoparticles (GNPs) immobilized on silanized glass act as an optical sensor that is able to quantify 1-butanethiol vapor. GNPs optical properties in the visible region are dominated by the surface plasmon resonance (SPR). The high affinity between 1-butanethiol and GNPs through Au-s bond leads to change in plasmon feature of GNPs that immobilized on silanized glass and causes absorption decrease at 542 nm in SPR spectrum of GNPs. It can be used as an optical sensor for quantitative detection. In this research, the glass slide surface activated by aminopropyltriethoxysilane (APTES). Spherical GNPs immobilized on silanized glass by silanization agent. The sensor is based on the spectrophotometry and digital color analysis (DCA) through RGB. We monitored R value and linear range 50-700 µM (R 2  =  0.97) with 2.05% relative standard deviation and 26.5 µM value was achieved, for the limit of detection. This method represents advantages of metal gold nanoparticles and solid substrate stability in one package, being inexpensive and low time consuming is another advantage of our method that can be conducted in petrochemical, pharmaceutical industries, and for detection of rotten food in food industries.

25th anniversary article: scalable multiscale patterned structures inspired by nature: the role of hierarchy.

PubMed

Bae, Won-Gyu; Kim, Hong Nam; Kim, Doogon; Park, Suk-Hee; Jeong, Hoon Eui; Suh, Kahp-Yang

2014-02-01

Multiscale, hierarchically patterned surfaces, such as lotus leaves, butterfly wings, adhesion pads of gecko lizards are abundantly found in nature, where microstructures are usually used to strengthen the mechanical stability while nanostructures offer the main functionality, i.e., wettability, structural color, or dry adhesion. To emulate such hierarchical structures in nature, multiscale, multilevel patterning has been extensively utilized for the last few decades towards various applications ranging from wetting control, structural colors, to tissue scaffolds. In this review, we highlight recent advances in scalable multiscale patterning to bring about improved functions that can even surpass those found in nature, with particular focus on the analogy between natural and synthetic architectures in terms of the role of different length scales. This review is organized into four sections. First, the role and importance of multiscale, hierarchical structures is described with four representative examples. Second, recent achievements in multiscale patterning are introduced with their strengths and weaknesses. Third, four application areas of wetting control, dry adhesives, selectively filtrating membranes, and multiscale tissue scaffolds are overviewed by stressing out how and why multiscale structures need to be incorporated to carry out their performances. Finally, we present future directions and challenges for scalable, multiscale patterned surfaces. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Multiple Auto-Adapting Color Balancing for Large Number of Images

NASA Astrophysics Data System (ADS)

Zhou, X.

2015-04-01

This paper presents a powerful technology of color balance between images. It does not only work for small number of images but also work for unlimited large number of images. Multiple adaptive methods are used. To obtain color seamless mosaic dataset, local color is adjusted adaptively towards the target color. Local statistics of the source images are computed based on the so-called adaptive dodging window. The adaptive target colors are statistically computed according to multiple target models. The gamma function is derived from the adaptive target and the adaptive source local stats. It is applied to the source images to obtain the color balanced output images. Five target color surface models are proposed. They are color point (or single color), color grid, 1st, 2nd and 3rd 2D polynomials. Least Square Fitting is used to obtain the polynomial target color surfaces. Target color surfaces are automatically computed based on all source images or based on an external target image. Some special objects such as water and snow are filtered by percentage cut or a given mask. Excellent results are achieved. The performance is extremely fast to support on-the-fly color balancing for large number of images (possible of hundreds of thousands images). Detailed algorithm and formulae are described. Rich examples including big mosaic datasets (e.g., contains 36,006 images) are given. Excellent results and performance are presented. The results show that this technology can be successfully used in various imagery to obtain color seamless mosaic. This algorithm has been successfully using in ESRI ArcGis.

Impact of Xanthylium Derivatives on the Color of White Wine.

PubMed

Bührle, Franziska; Gohl, Anita; Weber, Fabian

2017-08-19

Xanthylium derivatives are yellow to orange pigments with a glyoxylic acid bridge formed by dimerization of flavanols, which are built by oxidative cleavage of tartaric acid. Although their structure and formation under wine-like conditions are well established, knowledge about their color properties and their occurrence and importance in wine is deficient. Xanthylium cations and their corresponding esters were synthesized in a model wine solution and isolated via high-performance countercurrent chromatography (HPCCC) and solid phase extraction (SPE). A Three-Alternative-Forced-Choice (3-AFC) test was applied to reveal the color perception threshold of the isolated compounds in white wine. Their presence and color impact was assessed in 70 different wines (58 white and 12 rosé wines) by UHPLC-DAD-ESI-MS n and the storage stability in wine was determined. The thresholds in young Riesling wine were 0.57 mg/L (cations), 1.04 mg/L (esters) and 0.67 mg/L (1:1 ( w / w ) mixture), respectively. The low thresholds suggest a possible impact on white wine color, but concentrations in wines were below the threshold. The stability study showed the degradation of the compounds during storage under several conditions. Despite the low perception threshold, xanthylium derivatives might have no direct impact on white wine color, but might play a role in color formation as intermediate products in polymerization and browning.

Stability of color in Spanish-style green table olives pasteurized and stored in plastic containers.

PubMed

Sánchez, Antonio Higinio; López-López, Antonio; Beato, Víctor Manuel; de Castro, Antonio; Montaño, Alfredo

2017-08-01

There is an increasing interest in the use of pasteurizable plastic packaging by the olive industry. In order to investigate the change from traditional glass or varnished can containers to plastic packaging, the proper plastic material that is compatible with fermented olives while maintaining color quality during pasteurization treatment and storage must be selected. This work is focused on color stability in two distinct pasteurizable plastic containers with different oxygen permeability. In PET + MDPE/EVOH (polyethylene terephthalate + medium-density polyethylene/ethylene vinyl alcohol) pouches, pasteurization provoked severe browning which drastically decreased their color shelf life (<6 weeks). However, this browning did not occur in the unpasteurized product without preservatives owing to the presence of microorganisms. In AlOx-coated PET + MDPE (aluminum oxide coating on polyethylene terephthalate + medium-density polyethylene) pouches, color changes were small or negligible throughout storage, especially if ascorbic acid was added to the packing solution (shelf life > 6.5 months). The plastic material had a significant effect on the retention of color of the pasteurized product. The use of AlOx-coated PET + MDPE pouches could be an alternative to traditional packaging for the pasteurization and storage of Spanish-style green olives from a color quality standpoint. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

Surface modification of polyester fabrics by atmospheric-pressure air/He plasma for color strength and adhesion enhancement

NASA Astrophysics Data System (ADS)

Zhang, Chunming; Zhao, Meihua; Wang, Libing; Qu, Lijun; Men, Yajing

2017-04-01

Surface properties of water-based pigmented inks for ink-jet printed polyester fabrics were modified with atmospheric-pressure air/He plasma to improve the color strength and pigment adhesion of the treated surfaces. The influence of various parameters, including the surface morphology, chemical compositions, surface energy and dynamic contact angles of the control and plasma treated samples was studied. Color strength and edge definition were used to evaluate the ink-jet printing performance of fabrics. The change in pigment adhesion to polyester fibers was analyzed by SEM (scanning electron microscopy). AFM (Atomic force microscope) and XPS (X-ray photoelectron spectroscopy) analyses indicated the increase in surface roughness and the oxygen-containing polar groups(Cdbnd O, Csbnd OH and COOH) reinforced the fixation of pigments on the fiber surface. The result from this study suggested that the improved pigment color yield was clearly affected by alteration of pigment adhesion enhanced by plasma surface modification. Polyester fabrics exhibited better surface property and ink-jet printing performance after the air/He mixture plasma treatment comparing with those after air plasma treatment.

Red pigment from Lithospermum erythrorhizon by supercritical CO2 extraction.

PubMed

Lee, Hwa-Young; Kim, Yoon-Jung; Kim, Eun-Jung; Song, Young-Keun; Byun, Sang Yo

2008-01-01

In this study, a stable red pigment was prepared from Lithospermum erythrorhizon via supercritical carbon dioxide extraction. The optimal extraction conditions were 400 bar and 60 degrees C. The patch tests indicated that up to 10% of the red pigment was acceptable from a skin irritation standpoint. According to the results of the CIE LAB chromaticity test, the color difference was acceptable when compared to commercial synthetic red pigments. The light-illuminated color stability test indicated that the pigment was more stable than the red pigment extracted with ethanol. The higher stability was also demonstrated in the DPPH antioxidant activity test. The supercritical red pigment harbored elevated amounts of shikonin and derivatives, and appears to be usable as a stable red pigment for cosmetic color products.

Bi-functional anodic TiO2 oxide: Nanotubes for wettability control and barrier oxide for uniform coloring

NASA Astrophysics Data System (ADS)

Kim, Sunkyu; Jung, Minkyeong; Kim, Moonsu; Choi, Jinsub

2017-06-01

A uniformly colored TiO2, on which the surface is functionalized with nanotubes to control wettability, was prepared by a two-step anodization; the first anodization was carried out to prepare nanotubes for a super-hydrophilic or -hydrophobic surface and the second anodization was performed to fabricate a thin film barrier oxide to ensure uniform coloring. The effect of the nanotubes on barrier oxide coloring was examined by spectrophotometry and UV-vis-IR spectroscopy. We found four different regimes governing the color changes in terms of anodization voltage, indicating that the color of the duplex TiO2 was primarily determined by the thickness of the barrier oxide layer formed during the second anodization step. The surface wettability, as confirmed by the water contact angle, revealed that the single barrier TiO2 yielded 74.6° ± 2.1, whereas the nanotubes on the barrier oxide imparted super-hydrophilic properties as a result of increasing surface roughness as well as imparting a higher hydrophobicity after organic acid treatment.

Europa Global Views in Natural and Enhanced Colors

NASA Image and Video Library

1998-05-08

This color composite view combines violet, green, and infrared images of Jupiter intriguing moon, Europa, for a view of the moon in natural color left and in enhanced color designed to bring out subtle color differences in the surface right.

Surface-Plasmon Holography with White-Light Illumination

NASA Astrophysics Data System (ADS)

Ozaki, Miyu; Kato, Jun-ichi; Kawata, Satoshi

2011-04-01

The recently emerging three-dimensional (3D) displays in the electronic shops imitate depth illusion by overlapping two parallax 2D images through either polarized glasses that viewers are required to wear or lenticular lenses fixed directly on the display. Holography, on the other hand, provides real 3D imaging, although usually limiting colors to monochrome. The so-called rainbow holograms—mounted, for example, on credit cards—are also produced from parallax images that change color with viewing angle. We report on a holographic technique based on surface plasmons that can reconstruct true 3D color images, where the colors are reconstructed by satisfying resonance conditions of surface plasmon polaritons for individual wavelengths. Such real 3D color images can be viewed from any angle, just like the original object.

Munsell color analysis of Landsat color-ratio-composite images of limonitic areas in southwest New Mexico

NASA Technical Reports Server (NTRS)

Kruse, F. A.

1985-01-01

The causes of color variations in the green areas on Landsat 4/5-4/6-6/7 (red-blue-green) color-ratio-composite (CRC) images, defined as limonitic areas, were investigated by analyzing the CRC images of the Lordsburg, New Mexico area. The red-blue-green additive color system was mathematically transformed into the cylindrical Munsell color coordinates (hue, saturation, and value), and selected areas were digitally analyzed for color variation. The obtained precise color characteristics were then correlated with properties of surface material. The amount of limonite (L) visible to the sensor was found to be the primary cause of the observed color differences. The visible L is, is turn, affected by the amount of L on the material's surface and by within-pixel mixing of limonitic and nonlimonitic materials. The secondary cause of variation was vegetation density, which shifted CRC hues towards yellow-green, decreased saturation, and increased value.

Basic Research of Intrinsic Tamper Indication Markings Defined by Pulsed Laser Irradiation (Quad Chart).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moody, Neville R.

Objective: We will research how short (ns) and ultrashort (fs) laser pulses interact with the surfaces of various materials to create complex color layers and morphological patterns. Method: We are investigating the site-specific, formation of microcolor features. Also, research includes a fundamental study of the physics underlying periodic ripple formation during femtosecond laser irradiation. Status of effort: Laser induced color markings were demonstrated on an increased number of materials (including metal thin films) and investigated for optical properties and microstructure. Technology that allows for marking curved surfaces (and large areas) has been implemented. We have used electro-magnetic solvers to modelmore » light-solid interactions leading to periodic surface ripple patterns. This includes identifying the roles of surface plasmon polaritons. Goals/Milestones: Research corrosion resistance of oxide color markings (salt spray, fog, polarization tests); Through modeling, investigate effects of multi-source scattering and interference on ripple patterns; Investigate microspectrophotometry for mapping color; and Investigate new methods for laser color marking curved surfaces and large areas.« less

Cellulose nanocrystals (CNC) as carriers for a spirooxazine dye and its effect on photochromic efficiency.

PubMed

Sun, Bo; Hou, Qingxi; He, Zhibin; Liu, Zehua; Ni, Yonghao

2014-10-13

Nanocrystalline cellulose (CNC) as a renewable/sustainable material, has received much attention. Herein we studied CNC as carriers for a hydrophobic spirooxazine (SO)-based dye, 1,3-dihydro-1,3,3-trimethylspiro[2H-indole-2,3'-[3H]naphtha[2,1-b][1,4]oxazine], which may have potential applications in reversible memory photo-devices, textiles, photo-sensitive paper coatings, and inkjet printing inks. Due to the high cost and water-insolubility of this dye, it is desirable to improve its coloration efficiency and water-dispersibility. The experimental approach was to use CNC as carriers for the SO dye, thus obtaining a stable photochromic dye in aqueous systems. Transmission electron microscope (TEM) observation confirmed that the SO dye adsorbed on the surface of the CNC, which functioned as carriers for the photochromic dye. An impregnation process was adopted to anchor the dye onto cellulosic paper. It was found that the use of CNC resulted in a significant improvement in the SO coloration efficiency. The color stability and fatigue resistance were also studied. The use of CNC as carriers for a hydrophobic compound, its enhancement of associated properties, and its subsequent application were demonstrated. Copyright © 2014 Elsevier Ltd. All rights reserved.

Extra-weak chemiluminescence produced by autoxidation of kampo extract preparations stored in heat-stressed conditions.

PubMed

Sato, H; Hirayama, H; Yamamoto, T; Ishizawa, F; Mizugaki, M

1998-06-01

The purpose of this study was to evaluate the usefulness of extra-weak chemiluminescence (CL) measurement as a rapid method to estimate the stability of Kampo extract preparations. It was found that the Kampo drugs that emit little CL were stable, while those with higher CL were comparatively unstable with regard to the various stability markers, including change of coloration (browning), contents of specific ingredients, high molecular compounds, amino acids and sugars under various conditions of heat storage. Excellent correlation existed between the CL of Kampo drugs and the coloration (delta E* (ab)) and the other above-mentioned evaluation markers. From this investigation, it was deduced that the CL of Kampo drugs originates in the early stage of the Maillard reaction and reflects the stability of the preparations, and that CL is useful for estimating the stability of Kampo drugs.

Colorful Hydrophobic Poly(Vinyl Butyral)/Cationic Dye Fibrous Membranes via a Colored Solution Electrospinning Process

NASA Astrophysics Data System (ADS)

Yan, Xu; You, Ming-Hao; Lou, Tao; Yu, Miao; Zhang, Jun-Cheng; Gong, Mao-Gang; Lv, Fu-Yan; Huang, Yuan-Yuan; Long, Yun-Ze

2016-12-01

Colorful nanofibrous membranes have attracted much attention for their visual varieties and various functionalities. In this article, a colored solution electrospinning process was used to fabricate colorful hydrophobic poly(vinyl butyral) (PVB)/cationic dye nanofibrous membranes (NFMs) successfully. The color and morphology of these as-spun nanofibrous membranes have been analyzed by colorimetry, spectroscopy, and scanning electron microscopy (SEM). It is shown that the as-spun colorful PVB-based membranes exhibit excellent level-dyeing property and color stability. Furthermore, the doping of cationic dye and the increase of dye concentration can decrease the diameter of the as-spun colored fibers, which results in better level-dyeing property and higher water contact angle more than 140°. The stained PVB fibrous membranes with excellent level-dyeing property and hydrophobicity are promising in some applications such as textiles, wallpapers, and anticorrosive coating/painting.

Color calibration of an RGB camera mounted in front of a microscope with strong color distortion.

PubMed

Charrière, Renée; Hébert, Mathieu; Trémeau, Alain; Destouches, Nathalie

2013-07-20

This paper aims at showing that performing color calibration of an RGB camera can be achieved even in the case where the optical system before the camera introduces strong color distortion. In the present case, the optical system is a microscope containing a halogen lamp, with a nonuniform irradiance on the viewed surface. The calibration method proposed in this work is based on an existing method, but it is preceded by a three-step preprocessing of the RGB images aiming at extracting relevant color information from the strongly distorted images, taking especially into account the nonuniform irradiance map and the perturbing texture due to the surface topology of the standard color calibration charts when observed at micrometric scale. The proposed color calibration process consists first in computing the average color of the color-chart patches viewed under the microscope; then computing white balance, gamma correction, and saturation enhancement; and finally applying a third-order polynomial regression color calibration transform. Despite the nonusual conditions for color calibration, fairly good performance is achieved from a 48 patch Lambertian color chart, since an average CIE-94 color difference on the color-chart colors lower than 2.5 units is obtained.

Glu311 and Arg337 Stabilize a Closed Active-site Conformation and Provide a Critical Catalytic Base and Countercation for Green Bioluminescence in Beetle Luciferases.

PubMed

Viviani, V R; Simões, A; Bevilaqua, V R; Gabriel, G V M; Arnoldi, F G C; Hirano, T

2016-08-30

Beetle luciferases elicit the emission of different bioluminescence colors from green to red. Whereas firefly luciferases emit yellow-green light and are pH-sensitive, undergoing a typical red-shift at acidic pH and higher temperatures and in the presence of divalent heavy metals, click beetle and railroadworm luciferases emit a wider range of colors from green to red but are pH-independent. Despite many decades of study, the structural determinants and mechanisms of bioluminescence colors and pH sensitivity remain enigmatic. Here, through modeling studies, site-directed mutagenesis, and spectral and kinetic studies using recombinant luciferases from the three main families of bioluminescent beetles that emit different colors of light (Macrolampis sp2 firefly, Phrixotrix hirtus railroadworm, and Pyrearinus termitilluminans click beetle), we investigated the role of E311 and R337 in bioluminescence color determination. All mutations of these residues in firefly luciferase produced red mutants, indicating that the preservation of opposite charges and the lengths of the side chains of E311 and R337 are essential for keeping a salt bridge that stabilizes a closed hydrophobic conformation favorable for green light emission. Kinetic studies indicate that residue R337 is important for binding luciferin and creating a positively charged environment around excited oxyluciferin phenolate. In Pyrearinus green-emitting luciferase, the R334A mutation causes a 27 nm red-shift, whereas in Phrixotrix red-emitting luciferase, the L334R mutation causes a blue-shift that is no longer affected by guanidine. These results provide compelling evidence that the presence of arginine at position 334 is essential for blue-shifting the emission spectra of most beetle luciferases. Therefore, residues E311 and R337 play both structural and catalytic roles in bioluminescence color determination, by stabilizing a closed hydrophobic conformation favorable for green light emission, and also providing a base to accept excited oxyluciferin phenol proton, and a countercation to shield the negative charge of E311 and to stabilize excited oxyluciferin phenolate, blue-shifting emission spectra in most beetle luciferases.

Highly Efficient Simplified Single-Emitting-Layer Hybrid WOLEDs with Low Roll-off and Good Color Stability through Enhanced Förster Energy Transfer.

PubMed

Zhang, Dongdong; Cai, Minghan; Zhang, Yunge; Zhang, Deqiang; Duan, Lian

2015-12-30

Single-emitting layer hybrid white organic light-emitting diodes (SEL-hybrid-WOLEDs) usually suffer from low efficiency, significant roll-off, and poor color stability, attributed to the incomplete energy transfer from the triplet states of the blue fluorophores to the phosphors. Here, we demonstrate highly efficient SEL-hybrid-WOLEDs with low roll-off and good color-stability utilizing blue thermally activated delayed fluorescence (TADF) materials as the host emitters. The triplet states of the blue TADF host emitter can be up-converted into its singlet states, and then the energy is transferred to the complementary phosphors through the long-range Förster energy transfer, enhancing the energy transfer from the host to the dopant. Simplified SEL-hybrid-WOLEDs achieve the highest forward-viewing external quantum efficiency (EQE) of 20.8% and power efficiency of 51.2 lm/W with CIE coordinates of (0.398, 0.456) at a luminance of 500 cd/m(2). The device EQE only slightly drops to 19.6% at a practical luminance of 1000 cd/m(2) with a power efficiency of 38.7 lm/W. Furthermore, the spectra of the device are rather stable with the raising voltage. The reason can be assigned to the enhanced Förster energy transfer, wide charge recombination zone, as well as the bipolar charge transporting ability of the host emitter. We believe that our work may shed light on the future development of highly efficient SEL-hybrid-WOLEDs with simultaneous low roll-off and good color stability.

The Colors of Tethys II

NASA Image and Video Library

2015-07-29

This enhanced-color mosaic of Saturn's icy moon Tethys shows a range of features on the moon's trailing hemisphere. Tethys is tidally locked to Saturn, so the trailing hemisphere is the side of the moon that always faces opposite its direction of motion as it orbits the planet. This view was obtained about two and a half hours earlier than PIA19636 and shows terrain slightly farther to the west and south of that view. Two versions of the mosaic are presented here: one with standard image processing (Figure 1), and one that strongly enhances the relief of craters and other surface features (Figure 2). Images taken using clear, green, infrared and ultraviolet spectral filters were combined to create the view, which highlights subtle color differences across Tethys' surface at wavelengths not visible to human eyes. The moon's surface is fairly uniform in natural color. The color of the surface can be seen to change across the disk, from yellowish hues to nearly white. These broad color changes are affected by a number of external processes. First, Saturn's diffuse E-ring preferentially bombards Tethys' leading hemisphere, toward the right side in this image, with ice bright ice grains. At the same time, charged particles from Saturn's radiation belt bombard the surface on the trailing side, causing color changes due to chemical alteration of the materials there. The albedo -- a measure of the surface's reflectivity -- drops by 10 to 15 percent from the moon's leading side to the trailing side. Similar global color patterns exist on other Saturnian moons. On a much smaller scale, enigmatic, arc-shaped reddish streaks are faintly visible across the heavily-cratered surface, particularly in the upper right quarter of the image (see PIA19637 for a close-up view of these features). The origin of this localized color contrast is not yet understood. This mosaic is an orthographic projection constructed from 52 Cassini images obtained on April 11, 2015 with the Cassini spacecraft narrow-angle camera. Image scale is about 1,000 feet (300 meters) per pixel. The images were obtained at a distance of approximately 33,000 miles (53,000 kilometers) from Tethys. http://photojournal.jpl.nasa.gov/catalog/PIA19638

Cholesteric metronomes with flexoelectrically programmable amplitude

NASA Astrophysics Data System (ADS)

Joshi, Vinay; Varanytsia, A.; Chang, Kai-Han; Paterson, Daniel A.; Storey, John M. D.; Imrie, Corrie T.; Chien, Liang-Chy

2018-02-01

We experimentally demonstrate fast flexoelectro-optic switching in a liquid crystal cell containing bimesogen-doped and polymer-stabilized cholesteric. The device exhibits a response time of less than 0.7 ms and with low hysteresis and color dispersion which is suitable for potential applications including field-sequential color displays.

21 CFR 169.115 - French dressing.

Code of Federal Regulations, 2012 CFR

2012-04-01

..., lecithin, or polyglycerol esters of fatty acids. (d) Nomenclature. The name of the food is “French dressing...) Monosodium glutamate. (5) Tomato paste, tomato puree, catsup, sherry wine. (6) Eggs and ingredients derived from eggs. (7) Color additives that will impart the color traditionally expected. (8) Stabilizers and...

21 CFR 169.115 - French dressing.

Code of Federal Regulations, 2013 CFR

2013-04-01

..., lecithin, or polyglycerol esters of fatty acids. (d) Nomenclature. The name of the food is “French dressing...) Monosodium glutamate. (5) Tomato paste, tomato puree, catsup, sherry wine. (6) Eggs and ingredients derived from eggs. (7) Color additives that will impart the color traditionally expected. (8) Stabilizers and...

21 CFR 169.115 - French dressing.

Code of Federal Regulations, 2014 CFR

2014-04-01

..., lecithin, or polyglycerol esters of fatty acids. (d) Nomenclature. The name of the food is “French dressing...) Monosodium glutamate. (5) Tomato paste, tomato puree, catsup, sherry wine. (6) Eggs and ingredients derived from eggs. (7) Color additives that will impart the color traditionally expected. (8) Stabilizers and...

Shaded-Color Picture Generation of Computer-Defined Arbitrary Shapes

NASA Technical Reports Server (NTRS)

Cozzolongo, J. V.; Hermstad, D. L.; Mccoy, D. S.; Clark, J.

1986-01-01

SHADE computer program generates realistic color-shaded pictures from computer-defined arbitrary shapes. Objects defined for computer representation displayed as smooth, color-shaded surfaces, including varying degrees of transparency. Results also used for presentation of computational results. By performing color mapping, SHADE colors model surface to display analysis results as pressures, stresses, and temperatures. NASA has used SHADE extensively in sign and analysis of high-performance aircraft. Industry should find applications for SHADE in computer-aided design and computer-aided manufacturing. SHADE written in VAX FORTRAN and MACRO Assembler for either interactive or batch execution.

Satellite Applications to Acoustic Prediction Systems.

DTIC Science & Technology

1982-10-01

Spin Scan Radiometer (VISSR) Channlization. . .1. . . . . . . . * 0 .0 35 III Coastal Zone Color Scanner (CZCS) Channelization. • .o . ... ....... 38...surface condit.ions observable remotely by satellite include sea surface temperature, ocean color , and topography. C. EXPERINENTAL BASIS FOR THIS...resolution at infrared wavelengths) . The limbus-7 spacecraft carries the Coastal Zone Color Scanner (CZCS), which is a visual radiation instrument

Separate channels for processing form, texture, and color: evidence from FMRI adaptation and visual object agnosia.

PubMed

Cavina-Pratesi, C; Kentridge, R W; Heywood, C A; Milner, A D

2010-10-01

Previous neuroimaging research suggests that although object shape is analyzed in the lateral occipital cortex, surface properties of objects, such as color and texture, are dealt with in more medial areas, close to the collateral sulcus (CoS). The present study sought to determine whether there is a single medial region concerned with surface properties in general or whether instead there are multiple foci independently extracting different surface properties. We used stimuli varying in their shape, texture, or color, and tested healthy participants and 2 object-agnosic patients, in both a discrimination task and a functional MR adaptation paradigm. We found a double dissociation between medial and lateral occipitotemporal cortices in processing surface (texture or color) versus geometric (shape) properties, respectively. In Experiment 2, we found that the medial occipitotemporal cortex houses separate foci for color (within anterior CoS and lingual gyrus) and texture (caudally within posterior CoS). In addition, we found that areas selective for shape, texture, and color individually were quite distinct from those that respond to all of these features together (shape and texture and color). These latter areas appear to correspond to those associated with the perception of complex stimuli such as faces and places.

Color Analysis

NASA Astrophysics Data System (ADS)

Wrolstad, Ronald E.; Smith, Daniel E.

Color, flavor, and texture are the three principal quality attributes that determine food acceptance, and color has a far greater influence on our judgment than most of us appreciate. We use color to determine if a banana is at our preferred ripeness level, and a discolored meat product can warn us that the product may be spoiled. The marketing departments of our food corporations know that, for their customers, the color must be "right." The University of California Davis scorecard for wine quality designates four points out of 20, or 20% of the total score, for color and appearance (1). Food scientists who establish quality control specifications for their product are very aware of the importance of color and appearance. While subjective visual assessment and use of visual color standards are still used in the food industry, instrumental color measurements are extensively employed. Objective measurement of color is desirable for both research and industrial applications, and the ruggedness, stability, and ease of use of today's color measurement instruments have resulted in their widespread adoption.

Influence of artificial accelerated aging on the color stability and opacity of composites of different shades.

PubMed

Mundim, F M; Da Fonseca Roberti Garcia, L; Silva Sousa, A B; Cruvinel, D R; De Carvalho Panzeri Pires-De-Souza, F

2010-10-01

The aim of this study was to evaluate the influence of artificial accelerated aging on the color stability and opacity of composites of different shades. Four composites for direct use (Heliomolar, 4 Seasons, Tetric EvoCeram; QuiXfil) and one for indirect use (SR Adoro) in two shades were used: light (A2) and dark (C3 for direct, and D4 for indirect composite). QuiXfil was obtained in Universal shade. A Teflon matrix (12 X 2 mm) was used to obtain 54 specimens (N=6), which were submitted to color and opacity analysis (Spectrophotometer PCB 6807, Byk Gardner) before and after artificial accelerated aging for 384 hours. After the statistical analysis (2-way ANOVA - Bonferroni - P<0.05), significant color alteration was observed in the light and dark composites studied (P<0.05), with the exception of QuiXfil. Composite 4 Seasons/C3 showed less color alteration (ΔE=0.91). The opacity alteration (ΔOP) was higher for light composites. Artificial accelerated aging interfered in the optical properties assessed; however, the alterations seemed to be more related to the composites composition than to their shade.

High performance flexible top-emitting warm-white organic light-emitting devices and chromaticity shift mechanism

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shi, Hongying; Deng, Lingling; Chen, Shufen, E-mail: iamsfchen@njupt.edu.cn, E-mail: wei-huang@njupt.edu.cn

2014-04-15

Flexible warm-white top-emitting organic light-emitting devices (TEOLEDs) are fabricated onto PET substrates with a simple semi-transparent cathode Sm/Ag and two-color phosphors respectively doped into a single host material TCTA. By adjusting the relative position of the orange-red EML sandwiched between the blue emitting layers, the optimized device exhibits the highest power/current efficiency of 8.07 lm/W and near 13 cd/A, with a correlated color temperature (CCT) of 4105 K and a color rendering index (CRI) of 70. In addition, a moderate chromaticity variation of (-0.025, +0.008) around warm white illumination coordinates (0.45, 0.44) is obtained over a large luminance range ofmore » 1000 to 10000 cd/m{sup 2}. The emission mechanism is discussed via delta-doping method and single-carrier device, which is summarized that the carrier trapping, the exciton quenching, the mobility change and the recombination zone alteration are negative to color stability while the energy transfer process and the blue/red/blue sandwiched structure are contributed to the color stability in our flexible white TEOLEDs.« less

Effects of postexsanguination vascular infusion of cattle with a solution of saccharides, sodium chloride, phosphates, and vitamins C, E, or C+E on meat display-color stability.

PubMed

Yancey, E J; Hunt, M C; Dikeman, M E; Addis, P B; Katsanidis, E

2001-10-01

Grain-finished, high-percentage Charolais steers (n = 36) were selected for uniformity. Immediately after jugular vein exsanguination, 27 steers were infused at 10% of live weight via the carotid artery with a solution developed by MPSC, Inc. (St. Paul, MN) consisting of 98.52% water, 0.97% saccharides, 0.23% sodium chloride, and 0.28% phosphate blend plus either 500 ppm vitamin C (MPSC+C; n = 9), 500 ppm vitamin E (MPSC+E; n = 9), or 500 ppm vitamin C + 500 ppm vitamin E (MPSC+C+E; n = 9). Uninfused controls (CON) were exsanguinated conventionally. Carcasses were fabricated at 48 h postmortem. Longissimus thoracis (LT), psoas major (PM), and semimembranosus (SM) muscles were removed, vacuum-packaged, and stored at 2 degrees C until 14 d postmortem. Then, steaks 2.54 cm thick were sliced from the three muscles, placed on foam trays, and overwrapped with polyvinyl chloride film. Ground beef (GB) was formulated from the quadriceps femoris to contain 20% fat, mounded into 0.45-kg portions, placed on styrofoam trays, and wrapped with polyvinyl chloride film. Steaks were visually evaluated for uniformity and initial color on display d 0. Instrumental color measurements of L*, a*, b* and trained sensory panel color evaluations were obtained daily for 4 d (PM and GB) or 5 d (LT and SM) of display. No display time x treatment interaction existed for L*, a*, or b* values. The LT from CON cattle had more uniform color (P < 0.05) and was more cherry red than that from all infused cattle on d 0. Visual scores indicated that GB from MPSC+E cattle was more red (P < 0.05) than that from MPSC+C infused cattle throughout display, and GB from MPSC+E cattle was more red (P < 0.05) than that from CON cattle for the last 3 d of display. The vascular infusion solutions generally did not improve color or display-color stability of steaks, but the infusion solution with vitamin E did improve display-color stability of GB.

Working Memory Is Related to Perceptual Processing: A Case from Color Perception

ERIC Educational Resources Information Center

Allen, Elizabeth C.; Beilock, Sian L.; Shevell, Steven K.

2011-01-01

We explored the relation between individual differences in working memory (WM) and color constancy, the phenomenon of color perception that allows us to perceive the color of an object as relatively stable under changes in illumination. Successive color constancy (measured by first viewing a colored surface under a particular illumination and…

Antioxidant effects of soy sauce on color stability and lipid oxidation of raw beef patties during cold storage.

PubMed

Kim, Hyun-Wook; Choi, Yun-Sang; Choi, Ji-Hun; Kim, Hack-Youn; Hwang, Ko-Eun; Song, Dong-Heon; Lee, Soo-Yoen; Lee, Mi-Ai; Kim, Cheon-Jei

2013-11-01

This study was conducted to evaluate the antioxidant effects of soy sauce on lipid oxidation and color stability of raw beef patties. Raw beef patties were formulated with four solutions such as NaCl (sodium chloride solution), NaCl/SS (1:1 ratio of sodium chloride and soy sauce solution), SS (soy sauce solution), or SS/A (soy sauce solution combined with 0.05% ascorbic acid) in the same salt concentration. Addition of soy sauce resulted in the decreased pH, lightness, and increased yellowness. Treatment SS/A had the lowest percent of metmyoglobin during storage (P<0.05). A reduction (P<0.05) in the 2-thiobarbituric acid, peroxide, and conjugated diene concentration as result of soy sauce addition were observed in treatments SS and SS/A at the end of the storage period. There were no differences (P>0.05) in free fatty acid concentration at the end of storage. The combined addition of soy sauce and ascorbic acid greatly improved (P<0.05) color stability and retarded lipid oxidation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Natural colorants: Pigment stability and extraction yield enhancement via utilization of appropriate pretreatment and extraction methods.

PubMed

Ngamwonglumlert, Luxsika; Devahastin, Sakamon; Chiewchan, Naphaporn

2017-10-13

Natural colorants from plant-based materials have gained increasing popularity due to health consciousness of consumers. Among the many steps involved in the production of natural colorants, pigment extraction is one of the most important. Soxhlet extraction, maceration, and hydrodistillation are conventional methods that have been widely used in industry and laboratory for such a purpose. Recently, various non-conventional methods, such as supercritical fluid extraction, pressurized liquid extraction, microwave-assisted extraction, ultrasound-assisted extraction, pulsed-electric field extraction, and enzyme-assisted extraction have emerged as alternatives to conventional methods due to the advantages of the former in terms of smaller solvent consumption, shorter extraction time, and more environment-friendliness. Prior to the extraction step, pretreatment of plant materials to enhance the stability of natural pigments is another important step that must be carefully taken care of. In this paper, a comprehensive review of appropriate pretreatment and extraction methods for chlorophylls, carotenoids, betalains, and anthocyanins, which are major classes of plant pigments, is provided by using pigment stability and extraction yield as assessment criteria.

Color surface-flow visualization of fin-generated shock wave boundary-layer interactions

NASA Technical Reports Server (NTRS)

Lu, F. K.; Settles, G. S.

1990-01-01

Kerosene-lampblack mixtures with addition of a ground colored chalk were used in an experiment on visualizing surface flows of swept shock boundary-layer interactions. The results show that contrasting colors intensify the visualization of different regions of the interaction surface, and help the eye in following the fine streaks to locate the upstream influence. The study confirms observations of the separation occurring at shock strength below accepted values. The superiority of the reported technique over the previous monochrome technique is demonstrated.

Enhancing the chroma of pigmented polymers using antireflective surface structures.

PubMed

Clausen, Jeppe S; Christiansen, Alexander B; Kristensen, Anders; Mortensen, N Asger

2013-11-10

In this paper we investigate how the color of a pigmented polymer is affected by reduction of the reflectance at the air-polymer interface. Both theoretical and experimental investigations show modified diffuse-direct reflectance spectra when the reflectance of the surface is lowered. Specifically it is found that the color change is manifested as an increase in chroma, leading to a clearer color experience. The experimental implementation is done using random tapered surface structures replicated in polymer from silicon masters using hot embossing.

Color surface-flow visualization of fin-generated shock wave boundary-layer interactions

NASA Astrophysics Data System (ADS)

Lu, F. K.; Settles, G. S.

1990-03-01

Kerosene-lampblack mixtures with addition of a ground colored chalk were used in an experiment on visualizing surface flows of swept shock boundary-layer interactions. The results show that contrasting colors intensify the visualization of different regions of the interaction surface, and help the eye in following the fine streaks to locate the upstream influence. The study confirms observations of the separation occurring at shock strength below accepted values. The superiority of the reported technique over the previous monochrome technique is demonstrated.

Fabrication of multicolor fluorescent polyvinyl alcohol through surface modification with conjugated polymers by oxidative polymerization

NASA Astrophysics Data System (ADS)

Hai, Thien An Phung; Sugimoto, Ryuichi

2018-06-01

A simple method for the preparation of multicolor polyvinyl alcohol (PVA) by chemical oxidative polymerization is introduced. The PVA surface was successfully modified with conjugated polymers composed of 3-hexylthiophene (3HT) and fluorene (F). The incorporation of the 3HT/F copolymer onto the PVA surface was confirmed by Fourier-transform infrared (FT-IR), ultraviolet-visible (UV-vis), and fluorescence spectroscopies, X-ray diffraction (XRD), as well as thermogravimetric analysis (TGA), contact angle, and field-emission scanning electron microscopy (FE-SEM) coupled with energy dispersive X-ray (EDX) analysis. Different 3HT/F ratios on the PVA surface result in optical properties that include multicolor-emission and absorption behavior. The color of the resultant (3HT/F)-g-PVA shifted from red to blue, and the quantum yield increased with increasing F content. The surface hydrophobicity of the modified PVA increased significantly through grafting with the conjugated polymers, with the water contact angle increasing by 30° compared to pristine PVA. The PVA XRD peaks were less intense following surface modification. Thermogravimetric analyses reveal that the thermal stability of the PVA decreases as a result of grafting with the 3HT/F copolymers.

Science and engineering of nanodiamond particle surfaces for biological applications (Review).

PubMed

Shenderova, Olga A; McGuire, Gary E

2015-09-05

Diamond has outstanding bulk properties such as super hardness, chemical inertness, biocompatibility, luminescence, to name just a few. In the nanoworld, in order to exploit these outstanding bulk properties, the surfaces of nanodiamond (ND) particles must be accordingly engineered for specific applications. Modification of functional groups on the ND's surface and the corresponding electrostatic properties determine their colloidal stability in solvents, formation of photonic crystals, controlled adsorption and release of cargo molecules, conjugation with biomolecules and polymers, and cellular uptake. The optical activity of the luminescent color centers in NDs depends on their proximity to the ND's surface and surface termination. In order to engineer the ND surface, a fundamental understanding of the specific structural features and sp(3)-sp(2) phase transformations on the surface of ND particles is required. In the case of ND particles produced by detonation of carbon containing explosives (detonation ND), it should also be taken into account that its structure depends on the synthesis parameters and subsequent processing. Thus, for development of a strategy of surface modification of detonation ND, it is imperative to know details of its production. In this review, the authors discuss ND particles structure, strategies for surface modification, electrokinetic properties of NDs in suspensions, and conclude with a brief overview of the relevant bioapplications.

Method for Estimating the Charge Density Distribution on a Dielectric Surface.

PubMed

Nakashima, Takuya; Suhara, Hiroyuki; Murata, Hidekazu; Shimoyama, Hiroshi

2017-06-01

High-quality color output from digital photocopiers and laser printers is in strong demand, motivating attempts to achieve fine dot reproducibility and stability. The resolution of a digital photocopier depends on the charge density distribution on the organic photoconductor surface; however, directly measuring the charge density distribution is impossible. In this study, we propose a new electron optical instrument that can rapidly measure the electrostatic latent image on an organic photoconductor surface, which is a dielectric surface, as well as a novel method to quantitatively estimate the charge density distribution on a dielectric surface by combining experimental data obtained from the apparatus via a computer simulation. In the computer simulation, an improved three-dimensional boundary charge density method (BCM) is used for electric field analysis in the vicinity of the dielectric material with a charge density distribution. This method enables us to estimate the profile and quantity of the charge density distribution on a dielectric surface with a resolution of the order of microns. Furthermore, the surface potential on the dielectric surface can be immediately calculated using the obtained charge density. This method enables the relation between the charge pattern on the organic photoconductor surface and toner particle behavior to be studied; an understanding regarding the same may lead to the development of a new generation of higher resolution photocopiers.

Working memory is related to perceptual processing: a case from color perception.

PubMed

Allen, Elizabeth C; Beilock, Sian L; Shevell, Steven K

2011-07-01

We explored the relation between individual differences in working memory (WM) and color constancy, the phenomenon of color perception that allows us to perceive the color of an object as relatively stable under changes in illumination. Successive color constancy (measured by first viewing a colored surface under a particular illumination and later recalling it under a new illumination) was better for higher WM individuals than for lower WM individuals. Moreover, the magnitude of this WM difference depended on how much contextual information was available in the scene, which typically improves color constancy. By contrast, simple color memory, measured by viewing and recalling a colored surface under the same illumination, showed no significant relation to WM. This study reveals a relation between WM and a low-level perceptual process not previously thought to operate within the confines of attentional control, and it provides a first account of the individual differences in color constancy known about for decades.

Optimal color design of psychological counseling room by design of experiments and response surface methodology.

PubMed

Liu, Wenjuan; Ji, Jianlin; Chen, Hua; Ye, Chenyu

2014-01-01

Color is one of the most powerful aspects of a psychological counseling environment. Little scientific research has been conducted on color design and much of the existing literature is based on observational studies. Using design of experiments and response surface methodology, this paper proposes an optimal color design approach for transforming patients' perception into color elements. Six indices, pleasant-unpleasant, interesting-uninteresting, exciting-boring, relaxing-distressing, safe-fearful, and active-inactive, were used to assess patients' impression. A total of 75 patients participated, including 42 for Experiment 1 and 33 for Experiment 2. 27 representative color samples were designed in Experiment 1, and the color sample (L = 75, a = 0, b = -60) was the most preferred one. In Experiment 2, this color sample was set as the 'central point', and three color attributes were optimized to maximize the patients' satisfaction. The experimental results show that the proposed method can get the optimal solution for color design of a counseling room.

Resonant laser printing of structural colors on high-index dielectric metasurfaces

PubMed Central

Zhu, Xiaolong; Yan, Wei; Levy, Uriel; Mortensen, N. Asger; Kristensen, Anders

2017-01-01

Man-made structural colors, which originate from resonant interactions between visible light and manufactured nanostructures, are emerging as a solution for ink-free color printing. We show that non-iridescent structural colors can be conveniently produced by nanostructures made from high-index dielectric materials. Compared to plasmonic analogs, color surfaces with high-index dielectrics, such as germanium (Ge), have a lower reflectance, yielding a superior color contrast. Taking advantage of band-to-band absorption in Ge, we laser-postprocess Ge color metasurfaces with morphology-dependent resonances. Strong on-resonance energy absorption under pulsed laser irradiation locally elevates the lattice temperature (exceeding 1200 K) in an ultrashort time scale (1 ns). This forms the basis for resonant laser printing, where rapid melting allows for surface energy–driven morphology changes with associated modification of color appearance. Laser-printable high-index dielectric color metasurfaces are scalable to a large area and open a new paradigm for printing and decoration with nonfading and vibrant colors. PMID:28508062

Optimal Color Design of Psychological Counseling Room by Design of Experiments and Response Surface Methodology

PubMed Central

Chen, Hua; Ye, Chenyu

2014-01-01

Color is one of the most powerful aspects of a psychological counseling environment. Little scientific research has been conducted on color design and much of the existing literature is based on observational studies. Using design of experiments and response surface methodology, this paper proposes an optimal color design approach for transforming patients’ perception into color elements. Six indices, pleasant-unpleasant, interesting-uninteresting, exciting-boring, relaxing-distressing, safe-fearful, and active-inactive, were used to assess patients’ impression. A total of 75 patients participated, including 42 for Experiment 1 and 33 for Experiment 2. 27 representative color samples were designed in Experiment 1, and the color sample (L = 75, a = 0, b = -60) was the most preferred one. In Experiment 2, this color sample was set as the ‘central point’, and three color attributes were optimized to maximize the patients’ satisfaction. The experimental results show that the proposed method can get the optimal solution for color design of a counseling room. PMID:24594683

Working memory is related to perceptual processing: A case from color perception

PubMed Central

Allen, Elizabeth C.; Beilock, Sian L.; Shevell, Steven K.

2011-01-01

We explored the relation between individual differences in working memory (WM) and color constancy, the phenomenon of color perception that allows us to perceive the color of an object as relatively stable under changes in illumination. Successive color constancy (measured by first viewing a colored surface under a particular illumination and later recalling it under a new illumination) was better for higher-WM individuals than for lower-WM individuals. Moreover, the magnitude of this WM difference depended on how much contextual information was available in the scene, which typically improves color constancy. By contrast, simple color memory, measured by viewing and recalling a colored surface under the same illumination, showed no significant relation to WM. This study reveals a relation between WM and a low-level perceptual process not previously thought to operate within the confines of attentional control, and provides a first account of the individual differences in color constancy known about for decades. PMID:21480748

Separate whitening effects on enamel and dentin after fourteen days.

PubMed

Kugel, Gerard; Petkevis, Jason; Gurgan, Sevil; Doherty, Eileen

2007-01-01

The purpose of this study was to investigate the mechanism of action of a bleaching agent, as it relates to enamel and dentin. Twenty-six extracted human molar teeth were sectioned at the cemento-enamel junction and were randomly assigned to two groups. L*a*b* readings were taken with a spectrophotometer: on buccal surfaces of the crown, at enamel and dentin. The teeth were exposed to carbamide peroxide or placebo gel and L*a*b* scores were again recorded to determine color changes. Treatments were compared using ancova test with baseline color as the covariate. Relative to placebo, buccal surfaces exhibited the greatest Deltab* and DeltaL* color change. On buccal surfaces, the adjusted mean (SE) treatment differences were -7.8 (1.00) for Deltab* and 5.7 (0.97) for DeltaL, with groups differing significantly (p < 0.0001). On enamel surfaces, treatment differences were -3.6 (0.61) for Deltab* and 4.6 (0.80) for DeltaL* (p < 0.0001). Dentin exhibited the least color improvement. Adjusted mean (SE) treatment differences were -1.9 (0.87) for Deltab* and 2.4 (1.10) for DeltaL*, with groups differing significantly (p < 0.02) on dentin color change. The majority of color change seen on the buccal surface of tooth crowns exposed to carbamide peroxide 15% was because of the color change in enamel. As compared to enamel, dentin was less affected after 14 days.

[Aging of silorane- and methacrylate-based composite resins: effects on color and translucency].

PubMed

Liu, Chang; Pan, Jie; Lin, Hong; Shen, Song

2015-10-01

To evaluate the color stability and translucency of silorane-based low shrinkage composite after in vitro aging procedures of thermal cycling and water storage respectively, and to compare with those of conventional methacrylate-based posterior composite. Three light-cured composite resins, dimethacrylate-based composite A (Filtek™ Z350), B (Filtek™ P60) and silorane-based composite C (Filtek™ P90), were tested in this study. Ten specimens (10 mm in diameter, 1 mm in height) of each composite were prepared. The ten specimens in each group were then divided into two subgroups (n = 5). One subgroup underwent thermal cycling [(5.0 ± 0.5)~(55.0 ± 1.0) °C, 10 000 cycles] and the other was stored in 37 C° distilled water for 180 days. With a spectrophotometer, the CIE L * a * b * parameters of the specimens were tested before and after artificial aging against white, medium grey and black backgrounds, respectively. △E, TP and △TP were calculated and data were analyzed using independent-samples t test and partial analysis (P < 0.05). With regard to color stability, silorane-based composite showed color alteration above the clinically acceptable levels (△E > 3.3), and also showed higher △E with a statistically significant difference in comparison with the other composites (B and C) (P < 0.05) after artificial aging. With regard to translucency, composite C showed more alteration compared with composite B (P < 0.05) after thermal cycling. It may be concluded that the silorane-based composite underwent greater alteration with regard to color stability and translucency.

Conjugated polymer dots for ultra-stable full-color fluorescence patterning.

PubMed

Chang, Kaiwen; Liu, Zhihe; Chen, Haobin; Sheng, Lan; Zhang, Sean Xiao-An; Chiu, Daniel T; Yin, Shengyan; Wu, Changfeng; Qin, Weiping

2014-11-12

Stable full-color fluorescence patterning are achieved by multicolor polymer-dot inks. The fluorescent patterns show extraordinary stability upon various treatments, offering a superior combination of bright fluorescence, excellent photostability, chemical resistance, and eco-friendship. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Color Stability of Nanofilled and Microhybrid Resin-Based Composites Following Exposure to Chlorhexidine Mouthrinses: An In Vitro Study

PubMed Central

Khosravi, Mahmood; Esmaeili, Behnaz; Nikzad, Forough; Khafri, Soraya

2016-01-01

Objectives: This study aimed to evaluate the effects of chlorhexidine mouthrinses on color stability of nanofilled and micro-hybrid resin-based composites. Materials and Methods: In this in-vitro study, 160 disc-shaped specimens (7x2mm) were fabricated of Filtek Z250 and Filtek Z350XT Enamel (A2 shade). The samples of each group were randomly divided into eight subgroups (n=10). The specimens were incubated in artificial saliva at 37°C for 24 hours. The baseline color values (L*, a*, b*) of each specimen were measured according to CIE LAB system using a reflection spectrophotometer. After baseline color measurements, the control samples were immersed in saliva and the test groups were immersed in Kin (Cosmodent), Vi-One (Rozhin), Epimax (Emad), Hexodine (Donyaye Behdasht), Chlorhexidine (Shahrdaru), Najo (Najo) and Behsa (Behsa) mouthrinses once a day for two minutes. The specimens were then immersed again in saliva. This process was repeated for two weeks. Color measurements were made on days seven and 14. Two-way and one-way ANOVA and Tukey's post hoc test, t-test and paired t-test were used to analyze data at a significance level of 0.05. Results: All specimens displayed color change after immersion in the mouthrinses. Significant interactions were found between the effects of materials and mouthrinses on color change. Conclusions: All composite resins tested showed acceptable color change after immersion in different mouthrinses. Filtek Z350XT showed less color change than Filtek Z250. Mouthrinses containing alcohol (Behsa and Najo) and citric acid (Vi-One) caused greater discoloration of composites. PMID:27928240

[A preliminary study on the color effect of IPS Empress all-ceramic veneers].

PubMed

Li, Zhi-yong; Cheng, Xiang-rong; Wang, Yi-ning

2004-09-01

To evaluate the opaquing capacity, color compatibility and stability of IPS Empress all-ceramic veneers. A total of 86 IPS Empress all-ceramic veneers were made for 18 patients. The patients were divided into three groups: Group A was tetracycline teeth, 64 veneers for 5 patients; Group B was non-tetracycline teeth, 22 veneers for 13 patients; Group C was 22 natural vital teeth with normal color as control group. Before and after veneers were inserted, ShadeEye NCC was employed to obtain L * a * b * values of each tooth. The values of cemented veneers used as the baseline, the L * a * b * values of each veneer were measured half a year, 1 year, and 2 years after restoration respectively. All L * a * b * values at different evaluation times were analyzed by SPSS 10.0. Before and after veneers were restored, the L * a * b * values of both Group A and Group B were significantly different, the color difference being 5.01 and 4.15 respectively. The color difference between Group A and selected shade guides was 2.45. Compared with the baseline value, the L * value of Group A significantly decreased 2 years after restoration, but the DeltaE of different evaluation times was not significantly different. The color difference between Group B and Group C was 0.22 and there was no significant color difference after restoration. IPS Empress all-ceramic veneers have excellent opaquing capacity, color compatibility and stability to non-tetracycline teeth. To tetracycline teeth IPS Empress all-ceramic veneers have a certain opaquing capacity, but they cannot completely match with shade guides; the L * value is significantly different after restoration and further studies are needed to evaluate its color effect.

Association between modification of phenolic profiling and development of wine color during alcohol fermentation.

PubMed

Li, Si-Yu; Liu, Pei-Tong; Pan, Qiu-Hong; Shi, Ying; Duan, Chang-Qing

2015-04-01

To solve the problem of wine color instability in western China, different additives (the maceration enzymes Vinozym G and Ex-color, yeasts VR5 and Red Star, and commercial tannins) were added during alcoholic fermentation of Syrah (Vitis vinifera L.). The phenolic profile and color characteristics of wine were examined using high performance liquid chromatography mass spectrometry and CIELAB, respectively. The results showed that the combination of the enzyme Ex-color with the Red Star yeast eased the release of non-anthocyanins from grape berries into wine, whereas the use of enzyme Vinozym G and VR5 yeast enhanced the concentration of anthocyanins and achieved a higher red hue (a* value) and a lower yellow hue (b* value) in the wine. The addition of commercial tannins greatly promoted the level of gallic acid in the wine and led to a relatively higher concentration of anthocyanins. Partial least-squares regression analysis was used to find out the major phenolics, which were in close relation with color parameters; principal component analysis was used to evaluate the contribution of different winemaking techniques to wine color. The combination of these 2 analytic methods indicated that Vinozym G and VR5 yeast together with commercial tannins should be an appropriate combination to enhance the stability of wine color during alcohol fermentation, which was related to a significant increase in cyanidin-3-O-(6-O-acetyl)-glucoside, cyanidin-3-O-(6-O-coumaryl)-glucoside, trans-peonidin-3-O-(6-O-coumaryl)-glucoside, trans-malvidin-3-O-(6-O-coumaryl)-glucoside, and malvidin-3-O-(6-O-acetyl)-glucoside-pyruvic acid, all of which played an important role in stabilizing wine color. © 2015 Institute of Food Technologists®

Hair treatment process providing dispersed colors by light diffraction

DOEpatents

Sutton, Richard Matthew Charles; Lamartine, Bruce Carvell; Orler, E. Bruce; Song, Shuangqi

2015-12-22

A hair treatment process for providing dispersed colors by light diffraction including (a) coating the hair with a material comprising a polymer, (b) pressing the hair with a pressing device including one or more surfaces, and (c) forming a secondary nanostructured surface pattern on the hair that is complementary to the primary nanostructured surface pattern on the one or more surfaces of the pressing device. The secondary nanostructured surface pattern diffracts light into dispersed colors that are visible on the hair. The section of the hair is pressed with the pressing device for from about 1 to 55 seconds. The polymer has a glass transition temperature from about 55.degree. C. to about 90.degree. C. The one or more surfaces include a primary nanostructured surface pattern.

Synthesis of Zn1- x Co x Al2O4 Spinel Nanoparticles by Liquid-Feed Flame Spray Pyrolysis: Ceramic Pigments Application

NASA Astrophysics Data System (ADS)

Betancur Granados, Natalia; Yi, Eongyu; Laine, Richard M.; Restrepo Baena, Oscar Jaime

2016-01-01

Zn1- x Co x Al2O4 ( x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) spinel nanoparticles were synthesized by a liquid-feed flame spray pyrolysis (LF-FSP) method by combusting metallorganic precursor solutions to produce nanopowders with precise composition control. The precursor solutions were aerosolized into a methane/oxygen flame where it was combusted in an oxygen-rich environment to result in nanopowders at a single step. The nanopowders were analyzed by x-ray diffraction, Fourier transform infrared spectroscopy, colorimetry, field emission scanning electron microscopy, transmission electron microscopy, and BET (Brunauer-Emmett-Teller) N2 adsorption. Results show formation of spherical nanopowders with specific surface areas of 42 m2/g to 50 m2/g, which correspond to average particle sizes of 26 nm to 31 nm. Single-phase materials were obtained with a high control of composition, which indicates that LF-FSP is an excellent method to produce mixed-metal oxides for applications in which powder homogeneity is crucial. The products were evaluated for ceramic pigment application, where the ratio of Zn to Co was gradually changed to observe the color change in the structure with the increase of cobalt concentration. The resulting pigments were calcined at 1200°C, which aimed to identify the color stability after a high-temperature process, whereby the colors were measured using the color space CIE L*a*b* under standardized light, D65. Finally, the powders were tested for ceramic decoration using transparent glazes and ceramic bodies. The application was carried out at 1250°C to evaluate the color performance after a decoration process.

In vitro study of color stability of polycrystalline and monocrystalline ceramic brackets

PubMed Central

de Oliveira, Cibele Braga; Maia, Luiz Guilherme Martins; Santos-Pinto, Ary; Gandini Júnior, Luiz Gonzaga

2014-01-01

Objective The aim of this in vitro study was to analyze color stability of monocrystalline and polycrystalline ceramic brackets after immersion in dye solutions. Methods Seven ceramic brackets of four commercial brands were tested: Two monocrystalline and two polycrystalline. The brackets were immersed in four dye solutions (coffee, red wine, Coke and black tea) and in artificial saliva for the following times: 24 hours, 7, 14 and 21 days, respectively. Color changes were measured by a spectrophotometer. Data were assessed by Multivariate Profile Analysis, Analysis of Variance (ANOVA) and Multiple Comparison Tests of means. Results There was a perceptible change of color in all ceramic brackets immersed in coffee (ΔE* Allure = 7.61, Inspire Ice = 6.09, Radiance = 6.69, Transcend = 7.44), black tea (ΔE* Allure = 6.24, Inspire Ice = 5.21, Radiance = 6.51, Transcend = 6.14) and red wine (ΔE* Allure = 6.49, Inspire Ice = 4.76, Radiance = 5.19, Transcend = 5.64), but no change was noticed in Coke and artificial saliva (ΔE < 3.7). Conclusion Ceramic brackets undergo color change when exposed to solutions of coffee, black tea and red wine. However, the same crystalline structure, either monocrystalline or polycrystalline, do not follow the same or a similar pattern in color change, varying according to the bracket fabrication, which shows a lack of standardization in the manufacturing process. Coffee dye produced the most marked color changes after 21 days of immersion for most ceramic brackets evaluated. PMID:25279530

Color Stability of the Bulk-Fill Composite Resins with Different Thickness in Response to Coffee/Water Immersion

PubMed Central

Sheikh-Al-Eslamian, Seyedeh Mahsa; Hasani, Elham; Abrandabadi, Ahmad Najafi

2016-01-01

We aimed to evaluate the color stability of bulk-fill and conventional composite resin with respect to thickness and storage media. Twenty specimens of a conventional composite resin (6 mm diameter and 2 mm thick) and 40 specimens of the bulk-fill Tetric EvoCeram composite resin at two different thicknesses (6 mm diameter and 2 mm thick or 4 mm thick, n = 20) were prepared. The specimens were stored in distilled water during the study period (28 d). Half of the specimens were remained in distilled water and the other half were immersed in coffee solution 20 min/d and kept in distilled water between the cycles. Color changes (ΔE) were measured using the CIE L ⁎ a ⁎ b ⁎ color space and a digital imaging system at 1, 7, 14, and 28 days of storage. Data were analyzed using Two-way ANOVA and Tukey's HSD post hoc test (P < 0.05). Composite resins showed significant increase in color changes by time (bulk-fill > conventional; P < 0.001). Coffee exhibited significantly more staining susceptibility than that of distilled water (P < 0.001). There was greater color changes with increasing the increment thickness, which was significant at 14 (P < 0.001) and 28 d (P < 0.01). Color change of bulk-fill composite resin was greater than that of the conventional one after coffee staining and is also a function of increment thicknesses. PMID:27403163

In vitro study of color stability of polycrystalline and monocrystalline ceramic brackets.

PubMed

de Oliveira, Cibele Braga; Maia, Luiz Guilherme Martins; Santos-Pinto, Ary; Gandini Junior, Luiz Gonzaga

2014-01-01

The aim of this in vitro study was to analyze color stability of monocrystalline and polycrystalline ceramic brackets after immersion in dye solutions. Seven ceramic brackets of four commercial brands were tested: Two monocrystalline and two polycrystalline. The brackets were immersed in four dye solutions (coffee, red wine, Coke and black tea) and in artificial saliva for the following times: 24 hours, 7, 14 and 21 days, respectively. Color changes were measured by a spectrophotometer. Data were assessed by Multivariate Profile Analysis, Analysis of Variance (ANOVA) and Multiple Comparison Tests of means. There was a perceptible change of color in all ceramic brackets immersed in coffee (ΔE* Allure = 7.61, Inspire Ice = 6.09, Radiance = 6.69, Transcend = 7.44), black tea (ΔE* Allure = 6.24, Inspire Ice = 5.21, Radiance = 6.51, Transcend = 6.14) and red wine (ΔE* Allure = 6.49, Inspire Ice = 4.76, Radiance = 5.19, Transcend = 5.64), but no change was noticed in Coke and artificial saliva (ΔE < 3.7). Ceramic brackets undergo color change when exposed to solutions of coffee, black tea and red wine. However, the same crystalline structure, either monocrystalline or polycrystalline, do not follow the same or a similar pattern in color change, varying according to the bracket fabrication, which shows a lack of standardization in the manufacturing process. Coffee dye produced the most marked color changes after 21 days of immersion for most ceramic brackets evaluated.

Effect of preheat repetition on color stability of methacrylate- and silorane-based composite resins.

PubMed

Abed Kahnamouei, Mehdi; Gholizadeh, Sarah; Rikhtegaran, Sahand; Daneshpooy, Mehdi; Kimyai, Soodabeh; Alizadeh Oskoee, Parnian; Rezaei, Yashar

2017-01-01

Background. The aim of this study was to investigate the effect of preheating methacrylate- and silorane-based composite resins on their color stability up to 40 times at 55‒60°C. Methods. Seventy-six methacrylate and silorane-based composite resin samples, with a diameter of 10 mm and a height of 2 mm, were divided into 4 groups (n=19). After the samples were prepared, their color parameters were determined using a reflective spectrophotometer. The composite resin samples were separately stored in a solution of tea for 40 consecutive days. Then the samples underwent a color determination procedure again using a spectrophotometer and color changes were recorded. Finally two-way ANOVA was used to study the effect of composite temperature on its staining (P<0.05). Independent-samples t-test was used to evaluate changes in conversion rates of preheated composite resin samples compared to non-heated samples at P=0.005 and P=0.029 for silorane-based and Z250 composite resin samples, respectively. Results. Both composite resin type (P=0.014) and preheating (P<0.001) had significant effects on ΔE. Conclusion. Repeated preheating of methacrylate- and silorane-based composite resin samples, up to 55‒60°C for 40 rounds, resulted in more color changes compared with unheated composite resin samples. After storage in a solution of tea the color change rate in the composite resin samples of silorane-based was higher than the Z250 composite resin samples.

Effect of preheat repetition on color stability of methacrylate- and silorane-based composite resins

PubMed Central

Abed Kahnamouei, Mehdi; Gholizadeh, Sarah; Rikhtegaran, Sahand; Daneshpooy, Mehdi; Kimyai, Soodabeh; Alizadeh Oskoee, Parnian; Rezaei, Yashar

2017-01-01

Background. The aim of this study was to investigate the effect of preheating methacrylate- and silorane-based composite resins on their color stability up to 40 times at 55‒60°C. Methods. Seventy-six methacrylate and silorane-based composite resin samples, with a diameter of 10 mm and a height of 2 mm, were divided into 4 groups (n=19). After the samples were prepared, their color parameters were determined using a reflective spectrophotometer. The composite resin samples were separately stored in a solution of tea for 40 consecutive days. Then the samples underwent a color determination procedure again using a spectrophotometer and color changes were recorded. Finally two-way ANOVA was used to study the effect of composite temperature on its staining (P<0.05). Independent-samples t-test was used to evaluate changes in conversion rates of preheated composite resin samples compared to non-heated samples at P=0.005 and P=0.029 for silorane-based and Z250 composite resin samples, respectively. Results. Both composite resin type (P=0.014) and preheating (P<0.001) had significant effects on ΔE. Conclusion. Repeated preheating of methacrylate- and silorane-based composite resin samples, up to 55‒60°C for 40 rounds, resulted in more color changes compared with unheated composite resin samples. After storage in a solution of tea the color change rate in the composite resin samples of silorane-based was higher than the Z250 composite resin samples. PMID:29354248

Low levels of specularity support operational color constancy, particularly when surface and illumination geometry can be inferred

PubMed Central

Lee, Robert J.; Smithson, Hannah E.

2016-01-01

We tested whether surface specularity alone supports operational color constancy – the ability to discriminate changes in illumination or reflectance. Observers viewed short animations of illuminant or reflectance changes in rendered scenes containing a single spherical surface, and were asked to classify the change. Performance improved with increasing specularity, as predicted from regularities in chromatic statistics. Peak performance was impaired by spatial rearrangements of image pixels that disrupted the perception of illuminated surfaces, but was maintained with increased surface complexity. The characteristic chromatic transformations that are available with non-zero specularity are useful for operational color constancy, particularly if accompanied by appropriate perceptual organisation. PMID:26974938

Theoretical colours and isochrones for some Hubble Space Telescope colour systems. II

NASA Technical Reports Server (NTRS)

Paltoglou, G.; Bell, R. A.

1991-01-01

A grid of synthetic surface brightness magnitudes for 14 bandpasses of the Hubble Space Telescope Faint Object Camera is presented, as well as a grid of UBV, uvby, and Faint Object Camera surface brightness magnitudes derived from the Gunn-Stryker spectrophotometric atlas. The synthetic colors are used to examine the transformations between the ground-based Johnson UBV and Stromgren uvby systems and the Faint Object Camera UBV and uvby. Two new four-color systems, similar to the Stromgren system, are proposed for the determination of abundance, temperature, and surface gravity. The synthetic colors are also used to calculate color-magnitude isochrones from the list of theoretical tracks provided by VandenBerg and Bell (1990). It is shown that by using the appropriate filters it is possible to minimize the dependence of this color difference on metallicity. The effects of interstellar reddening on various Faint Object Camera colors are analyzed as well as the observational requirements for obtaining data of a given signal-to-noise for each of the 14 bandpasses.

Water color and circulation southern Chesapeake Bay, part 1

NASA Technical Reports Server (NTRS)

Nichols, M. M.; Gordon, H. H.

1975-01-01

Satellite imagery from two EREP passes over the Rappahannock Estuary of the Chesapeake region is analyzed to chart colored water types, to delineate color boundaries and define circulatory patterns. Surface observations from boats and helicopters concurrent with Skylab overpass define the distributions of suspended sediment, transparency, temperature, salinity, phytoplankton, color of suspended material and optical ratio. Important features recorded by the imagery are a large-scale turbidity maximum and massive red tide blooms. Water movement is revealed by small-scale mixing patterns and tidal plumes of apparent sediment-laden water. The color patterns broadly reflect the bottom topography and the seaward gradient of suspended material between the river and the bay. Analyses of red, green and natural color photos by microdensitometry demonstrate the utility of charting water color types of potential use for managing estuarine water quality. The Skylab imagery is superior to aerial photography and surface observations for charting water color.

Iridescence of a shell of mollusk Haliotis Glabra

NASA Astrophysics Data System (ADS)

Tan, T. L.; Wong, D.; Lee, Paul

2004-10-01

Pearls and shells of some mollusks are attractive inorganic materials primarily owing to the beauty of their natural lustrous and iridescent surface. The iridescent colors can be explained by diffraction or interference or both, depending on the microstructure of the surface. Strong iridescent colors are very evident on the polished shell of the mollusk Haliotis Glabra, commonly known as abalone. It would be interesting to study how these colors are produced on the surface of the shell. By using a scanning electron microscope (SEM), the surface of the shell is found to have a fine-scale diffraction grating structure, and stacks of thin crystalline nacreous layers or platelets are found below the surface. These observations suggest that the iridescent colors are caused by both diffraction and interference. From measurements done on the diffraction patterns that were obtained using a He-Ne laser illuminating the shell, the groove width of the grating structure was derived. Good agreement was found between the derived groove density by diffraction and that measured directly using the SEM. The crystalline structure of the nacreous layers of the shell is studied using Fourier transform infrared spectroscopy and SEM observations. The infrared absorption peaks of 700, 713, 862 and 1083 cm-1 confirmed that the nacre of the shell is basically aragonite. The strong iridescent colors of the shell are the result of high groove density on the surface which causes diffraction. The uniform stacking of layers of nacre below the surface of the shell also causes interference effects that contribute to the iridescent colors.

Effect of bleaching on color change and surface topography of composite restorations.

PubMed

Pruthi, Gunjan; Jain, Veena; Kandpal, H C; Mathur, Vijay Prakash; Shah, Naseem

2010-01-01

This study was conducted to determine the effect of 15% carbamide peroxide bleaching agent on color change and surface topography of different composite veneering materials (Filtek Z350 (3M ESPE), Esthet X (Dentsply India), and Admira (Voco, Germany). Methods. 30 samples were fabricated for evaluation of color change using CIELAB color system and Gonioreflectometer (GK 311/M, ZEISS). 45 disc-shaped specimens were made for evaluation of surface topography after bleaching (Nupro White Gold; Dentsply) using SEM. Statistical analysis. One way ANOVA and Multiple comparison tests were used to analyze the data. Statistical significance was declared if the P value was .05 or less. Results and conclusion. All the specimens showed significant discoloration (ΔE > 3.3) after their immersion in solutions representing food and beverages. The total color change after bleaching as compared to baseline color was significant in Filtek Z350 (P = .000) and Esthet X (P = .002), while it was insignificant for Admira (P = .18). Esthet X showed maximum surface roughness followed by Admira and Filtek Z350. Bleaching was effective in reducing the discoloration to a clinically acceptable value in all the three groups (ΔE < 3.3).

True Color and Chromaticity of the Martian Surface and Sky from Mars Exploration Rover Pancam Observations

NASA Astrophysics Data System (ADS)

Savransky, D.; Bell, J. F.

2004-12-01

We calculate the quantitative color of Mars using calibrated data from the Panoramic Cameras (Pancams) on the Mars Exploration Rovers Spirit and Opportunity. Measured color values allow us to directly compare the color properties of the rover landing sites with the Mars Pathfinder and Viking Lander sites, to quantify systematic changes in color over time, and to increase our perceptual understanding of conditions on the Martian surface. By converting calculated color values to the sRGB color space employed by the majority of modern computer monitors and printers, "true color" representations of the martian surface and sky are produced. Initial colorimetry values are calculated as CIE tristimulus values (the red, green, and blue components of human color vision). Calibrated radiance images from the six discrete left eye Pancam narrow band filters (centered at 753, 673, 601, 535, 482, and 432 nm) are splined to estimate an entire human visible spectrum (360 to 830 nm) for each pixel. Tristimulus values are found by discretely summing over the products of the spectra and 3 CIE color matching functions, allowing chromaticities (normalized tristimulus values) to be calculated. CIE tristimulus values are convolved with a transformation matrix to create sRGB tristimulus values which are then fit to a 2.2 gamma curve and scaled to the range of 0 to 255, 24 bit encoding (8 bits/channel) used by the majority of color displays. An average normalized surface spectrum is used to approximate chromaticities for images with only partial left eye filter sets. Chromaticity values of the martian sky and surface at various points throughout the mission generally match those from the Pathfinder and Viking landing sites. Using the color designation method defined by the ISCC-NBS, the martian sky is "light to moderate yellowish brown," while average rocks and soil vary between "dark grayish yellowish brown" to "moderate brown". Study of changes in the colors of the rover calibration targets over the first 200 sols of each mission show that the chromaticities are trending towards the "dark yellowish brown" portion of the color space, indicating that the calibration targets are getting covered by martian dust as the mission progresses and allowing a quantitative estimate of dust deposition rates. A similar study of sky chromaticities throughout the missions shows trends in the color of the sky towards "very light yellowish brown." Comparing these trends with measured dust opacities throughout the missions would predict that, to the human eye, the "true" martian sky (with no suspended dust) would appear a very light yellowish brown color - almost directly opposite from the color of Earth's sky. However, this hypothesis needs to be tested against multiple scattering radiative transfer models of the martian sky radiance field.

Breaking object correspondence across saccades impairs object recognition: The role of color and luminance.

PubMed

Poth, Christian H; Schneider, Werner X

2016-09-01

Rapid saccadic eye movements bring the foveal region of the eye's retina onto objects for high-acuity vision. Saccades change the location and resolution of objects' retinal images. To perceive objects as visually stable across saccades, correspondence between the objects before and after the saccade must be established. We have previously shown that breaking object correspondence across the saccade causes a decrement in object recognition (Poth, Herwig, & Schneider, 2015). Color and luminance can establish object correspondence, but it is unknown how these surface features contribute to transsaccadic visual processing. Here, we investigated whether changing the surface features color-and-luminance and color alone across saccades impairs postsaccadic object recognition. Participants made saccades to peripheral objects, which either maintained or changed their surface features across the saccade. After the saccade, participants briefly viewed a letter within the saccade target object (terminated by a pattern mask). Postsaccadic object recognition was assessed as participants' accuracy in reporting the letter. Experiment A used the colors green and red with different luminances as surface features, Experiment B blue and yellow with approximately the same luminances. Changing the surface features across the saccade deteriorated postsaccadic object recognition in both experiments. These findings reveal a link between object recognition and object correspondence relying on the surface features colors and luminance, which is currently not addressed in theories of transsaccadic perception. We interpret the findings within a recent theory ascribing this link to visual attention (Schneider, 2013).

Self-Assembly Driven Aggregation-Induced Emission of Copper Nanoclusters: A Novel Technology for Lighting.

PubMed

Liu, Yi; Yao, Dong; Zhang, Hao

2018-04-18

Because of the specific properties including HOMO-LUMO electronic transition, size-dependent fluorescent emission, and intense light absorption, metal nanoclusters (NCs) have been considered to be one of the most competitive color conversion materials in light-emitting diodes (LEDs). However, the monotonous emission color and the low emission stability and intensity of individual metal NCs strongly limit their universal application. Inspired by the concept of "aggregation-induced emission" (AIE), the utilization of highly ordered metal NC assemblies opens a door to resolve these problems. After self-assembly, the emission stability and intensity of metal NC assemblies are enhanced. At the same time, the emission color of metal NC assemblies become tunable. We termed this process as self-assembly driven AIE of metal NCs. In this review, we use Cu NCs as the example to convey the concept that the compact and ordered arrangement can efficiently improve the metal NCs' emission stability, tunability, and intensity. We first introduce the synthesis of 2D Cu NC self-assemblies and their emissions. We further summarize some of the factors that can affect the emissions of 2D Cu NC self-assemblies. We then discuss the utilization of 2D Cu NC self-assemblies as color conversion materials for LEDs. At last, we outline current challenges and our perspectives on the development of this area.

New iridium dopants forg white phosphorescent devices: enhancement of efficiency and color stability by an energy-harvesting layer.

PubMed

Chou, Ho-Hsiu; Li, Yi-Kai; Chen, Yu-Han; Chang, Ching-Chih; Liao, Chuang-Yi; Cheng, Chien-Hong

2013-07-10

A new light blue complex (fmoppy)2Ir(tfpypz) [bis(4'-fluoro-6'-methoxylphenyl pyridinato)-iridium(III)-3-(trifluoromethyl)-5-(pyridin-2-yl)-1,2,4-triazolate] and a new orange complex (dpiq)2Ir(acac) [bis(3,4-diphenylisoquinoline)-iridium(III)-acetylacetonate] were synthesized. These two complexes were used as the dopants for the fabrication of two-element white phosphorescent devices. Via the introduction of a thin energy-harvesting layer (EHL) to harvest the extra energy and exciton from the emission zone, highly efficient two-element white devices with excellent color stability were created. One of the best devices shows yellow-white color emission with an extremely high external quantum efficiency (EQE) of 21.5% and a current efficiency of 68.8 cd/A. The other device gave a pure white emission with an external quantum efficiency of 19.2% and a current efficiency of 53.2 cd/A. At a high brightness of 1000 cd/m(2), the EQE still remains as high as 18.9 and 17.2%. With a brightness of 1000-10000 cd/m(2), the CIE coordinates of these two devices shift by only (0.02, ≤0.01). The white phosphorescent devices with the EHL showed much higher efficiency and better color stability than the one without the EHL.

Storage ring two-color free-electron laser

DOE PAGES

Yan, J.; Hao, H.; Li, J. Y.; ...

2016-07-05

We report a systematic experimental study of a storage ring two-color free-electron laser (FEL) operating simultaneously in the infrared (IR) and ultraviolet (UV) wavelength regions. The two-color FEL lasing has been realized using a pair of dual-band high-reflectivity FEL mirrors with two different undulator configurations. We have demonstrated independent wavelength tuning in a wide range for each lasing color, as well as harmonically locked wavelength tuning when the UV lasing occurs at the second harmonic of the IR lasing. Precise power control of two-color lasing with good power stability has also been achieved. In addition, the impact of the degradationmore » of FEL mirrors on the two-color FEL operation is reported. Moreover, we have investigated the temporal structures of the two-color FEL beams, showing simultaneous two-color micropulses with their intensity modulations displayed as FEL macropulses.« less

The "Chocolate Experiment"--A Demonstration of Radiation Absorption by Different Colored Surfaces

ERIC Educational Resources Information Center

Fung, Dennis

2015-01-01

In the typical "cookbook" experiment comparing the radiation absorption rates of different colored surfaces, students' hands are commonly used as a measurement instrument to demonstrate that dull black and silvery surfaces are good and poor absorbers of radiation, respectively. However, college students are often skeptical about using…

7 CFR 51.1830 - Fairly well colored.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Fairly well colored. 51.1830 Section 51.1830... STANDARDS) United States Standards for Grades of Florida Tangerines Definitions § 51.1830 Fairly well colored. Fairly well colored means that the surface of the fruit may have green color which does not...

7 CFR 51.1830 - Fairly well colored.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly well colored. 51.1830 Section 51.1830... STANDARDS) United States Standards for Grades of Florida Tangerines Definitions § 51.1830 Fairly well colored. Fairly well colored means that the surface of the fruit may have green color which does not...

Simultaneous Luminescence Pressure and Temperature Measurement System for Hypersonic Wind Tunnels

NASA Technical Reports Server (NTRS)

Buck, Gregory M.

1995-01-01

Surface pressures and temperatures are determined from visible emission brightness and green-to-red color ratioing of induced luminescence from a ceramic surface with an organic dye coating. A ceramic-dye matrix of porous silica ceramic with an adsorbed dye is developed for high-temperature pressure sensitivity and stability (up to 150 C). Induced luminescence may be excited using a broad range of incident radiation from visible blue light (488-nm wavelength) to the near ultraviolet (365 nm). Ceramic research models and test samples are fabricated using net-form slip-casting and sintering techniques. Methods of preparation and effects of adsorption film thickness on measurement sensitivity are discussed. With the present 8-bit imaging system a 10% pressure measurement uncertainty from 50 to 760 torr is estimated, with an improvement to 5% from 3 to 1500 torr with a 12-bit imaging system.

Interaction of aromatic amines with iron oxides: implications for prebiotic chemistry.

PubMed

Shanker, Uma; Singh, Gurinder; Kamaluddin

2013-06-01

The interaction of aromatic amines (aniline, p-chloroaniline, p-toludine and p-anisidine) with iron oxides (goethite, akaganeite and hematite) has been studied. Maximum uptake of amines was observed around pH 7. The adsorption data obtained at neutral pH were found to follow Langmuir adsorption. Anisidine was found to be a better adsorbate probably due to its higher basicity. In alkaline medium (pH > 8), amines reacted on goethite and akaganeite to give colored products. Analysis of the products by GC-MS showed benzoquinone and azobenzene as the reaction products of aniline while p-anisidine afforded a dimer. IR analysis of the amine-iron oxide hydroxide adduct suggests that the surface acidity of iron oxide hydroxides is responsible for the interaction. The present study suggests that iron oxide hydroxides might have played a role in the stabilization of organic molecules through their surface activity and in prebiotic condensation reactions.

Controlled oxide films formation by nanosecond laser pulses for color marking.

PubMed

Veiko, Vadim; Odintsova, Galina; Ageev, Eduard; Karlagina, Yulia; Loginov, Anatoliy; Skuratova, Alexandra; Gorbunova, Elena

2014-10-06

A technology of laser-induced coloration of metals by surface oxidation is demonstrated. Each color of the oxide film corresponds to a technologic chromacity coefficient, which takes into account the temperature of the sample after exposure by sequence of laser pulses with nanosecond duration and effective time of action. The coefficient can be used for the calculation of laser exposure regimes for the development of a specific color on the metal. A correlation between the composition of the films obtained on the surface of stainless steel AISI 304 and commercial titanium Grade 2 and its color and chromacity coordinates is shown.

Amplification of interference color by using liquid crystal for protein detection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Qingdi; Yang, Kun-Lin, E-mail: cheyk@nus.edu.sg

Micrometer-sized, periodic protein lines printed on a solid surface cause interference color which is invisible to the naked eye. However, the interference color can be amplified by using a thin layer of liquid crystal (LC) covered on the surface to form a phase diffraction grating. Strong interference color can thus be observed under ambient light. By using the LC-amplified interference color, we demonstrate naked-eye detection of a model protein—immunoglobulin G (IgG). Limit of detection can reach 20 μg/ml of IgG without using any instrumentation. This detection method is potentially useful for the development of low-cost and portable biosensors.

Effects of polishing on surface roughness, gloss and color of surface reaction type pre-reacted glass-ionomer filled resin composite.

PubMed

Hosoya, Yumiko; Shiraishi, Takanobu; Odatsu, Tetsuro; Miyazaki, Masashi; García-Godoy, Franklin

2011-06-01

To evaluate the effects of polishing on surface roughness, gloss and color of different shades of surface reaction type pre-reacted glass-ionomer (S-PRG) filled nano-hybrid resin composite. Resin disks of 15 mm diameter and 2 mm thickness and final polish with 1000-grit SiC paper, super fine cut diamond (FG) point, silicon (MFR) point and Super-Snap mini-disk red (SNAP) were made with Beautifil II shades: A2, A20, Inc). One week after curing, the surface roughness, gloss and color were measured. Data was analyzed with ANOVA and Fisher's PLSD with alpha= 0.05 For all shades, the order of roughness (Ra) ranked according to groups of 1000-grit SiC > FG > MFR > SNAP with significant differences among all groups. For all shades, the order of gloss ranked according to groups of SNAP > MFR > FG > 1000-grit SiC with significant differences among the groups except for between MFR and FG without significant difference. The influence of the surface roughness on color differed among the polishing groups and shades. However, the values of the color differences (deltaE*ab) between the polishing groups of all shades were imperceptible to the naked eye.

Colorimetric Sensor for Label Free Detection of Porcine PCR Product (ID: 18)

NASA Astrophysics Data System (ADS)

Ali, M. E.; Hashim, U.; Bari, M. F.; Dhahi, Th. S.

2011-05-01

This report described the use of 40±5 nm in diameter citrate-coated gold nanoparticles (GNPs) as colorimetric sensor to visually detect the presence of a 17-base swine specific conserved sequence and nucleotide mismatch in the mixed PCR products of pig, deer and shad cytochrome b genes. The size of these PCR amplicons was 109 base-pair and was amplified with a pair of common primers. Colloidal GNPs changed color from pinkish- red to purple-gray in 2 mM PBS buffer by losing its characteristic surface plasmon resonance peak at 530 nm and gaining new features between 620 and 800 nm in the absorption spectrum indicating strong aggregation. The particles were stabilized against salt induced aggregation, retained spectral features and characteristic color upon adsorption of single-stranded DNA. The PCR products without any additional processing were hybridized with a 17-nucleotide swine probe prior to exposure to GNPs. At a critical annealing temperature (55° C) that differentiated between the match and mismatch pairing, the probe was hybridized with the pig PCR product and dehybridized from the deer's and shad's. The interaction of dehybridized probe to GNPs prevented them from salt-induced aggregation, retaining their characteristic red color. The assay did not need any surface modification chemistry or labeling steps. The results were determined visually and validated by absorption spectroscopy. The entire assay (hybridization plus visual detection) was performed in less than 10 min. The assay obviated the need of complex RFLP, sequencing or blotting to differentiate the same size PCR products. We find the application of the assay for species assignment in food analysis, mismatch detection in genetic screening and homology study among closely related species.

Biological soil crusts exhibit a dynamic response to seasonal rain and release from grazing with implications for soil stability

USGS Publications Warehouse

Jimenez, Aguilar A.; Huber-Sannwald, E.; Belnap, J.; Smart, D.R.; Arredondo, Moreno J.T.

2009-01-01

In Northern Mexico, long-term grazing has substantially degraded semiarid landscapes. In semiarid systems, ecological and hydrological processes are strongly coupled by patchy plant distribution and biological soil crust (BSC) cover in plant-free interspaces. In this study, we asked: 1) how responsive are BSC cover/composition to a drying/wetting cycle and two-year grazing removal, and 2) what are the implications for soil erosion? We characterized BSC morphotypes and their influence on soil stability under grazed/non-grazed conditions during a dry and wet season. Light- and dark-colored cyanobacteria were dominant at the plant tussock and community level. Cover changes in these two groups differed after a rainy season and in response to grazing removal. Lichens with continuous thalli were more vulnerable to grazing than those with semi-continuous/discontinuous thalli after the dry season. Microsites around tussocks facilitated BSC colonization compared to interspaces. Lichen and cyanobacteria morphotypes differentially enhanced resistance to soil erosion; consequently, surface soil stability depends on the spatial distribution of BSC morphotypes, suggesting soil stability may be as dynamic as changes in the type of BSC cover. Longer-term spatially detailed studies are necessary to elicit spatiotemporal dynamics of BSC communities and their functional role in biotically and abiotically variable environments. ?? 2009 Elsevier Ltd.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yan, J.; Hao, H.; Li, J. Y.

We report a systematic experimental study of a storage ring two-color free-electron laser (FEL) operating simultaneously in the infrared (IR) and ultraviolet (UV) wavelength regions. The two-color FEL lasing has been realized using a pair of dual-band high-reflectivity FEL mirrors with two different undulator configurations. We have demonstrated independent wavelength tuning in a wide range for each lasing color, as well as harmonically locked wavelength tuning when the UV lasing occurs at the second harmonic of the IR lasing. Precise power control of two-color lasing with good power stability has also been achieved. In addition, the impact of the degradationmore » of FEL mirrors on the two-color FEL operation is reported. Moreover, we have investigated the temporal structures of the two-color FEL beams, showing simultaneous two-color micropulses with their intensity modulations displayed as FEL macropulses.« less

Color Image of Phoenix Lander on Mars Surface

NASA Image and Video Library

2008-05-27

This is an enhanced-color image from Mars Reconnaissance Orbiter High Resolution Imaging Science Experiment HiRISE camera. It shows the NASA Mars Phoenix lander with its solar panels deployed on the Mars surface

Effects of adhesive used as modeling liquid on the stability of the color and opacity of composites.

PubMed

Araujo, Fernanda Santos; Barros, Mellany Cristie Ramos; Santana, Márcia Luciana Carregosa; de Jesus Oliveira, Ludmila Smith; Silva, Paula Fernanda Damasceno; Lima, Giana da Silveira; Faria-E-Silva, André Luis

2018-04-01

This study evaluated the effects of adhesive type used as modeling liquid on the stability of the color and opacity of composites submitted to thermal cycling in staining solutions followed by a bleaching procedure. Thirty cylinder-shaped composite specimens (10 mm diameter × 1.5 mm thickness) were built using or not using (control) an adhesive (Adper Universal or Scotchbond Multipurpose) as the modeling liquid. After polishing procedures, the color and opacity were measured, and the specimens were submitted to 200 thermal cycles with 10 s of dwell time in baths of grape juice at 5°C, water at 37°C, and coffee at 55°C. Changes in opacity and color caused by the staining solutions were measured. Then, the specimens were bleached with 35% hydrogen peroxide for 45 minutes followed by color/opacity measurements. Data were analyzed by ANOVA and Tukey's test (α = 0.05). The use of modeling liquids did not affect the initial color and opacity of composite. Reduced changes to color (E 00  = 3.44) and opacity (+2.67%) were observed for specimens modeled using Adper Universal. Bleaching procedures reduced the color (E 00  = 1.9-3.8) and opacity (-2.3 to 3.1%) alterations caused by staining solutions but were unable to restore the values observed at baseline. The use of universal adhesive as modeling liquid significantly reduced the color and opacity changes caused by staining solutions, and the bleaching procedure partially re-established the opacity and color of the composites. This study evaluates whether using adhesive systems for modeling a composite affects the color and opacity changes caused by staining solutions followed by a bleaching procedure. The findings suggest that the use of a universal adhesive as modeling liquid can reduce the alterations in optical properties caused by staining solutions, and the application of high-concentrated hydrogen peroxide over the composite reduce the color changes without fully recover the initial color. © 2018 Wiley Periodicals, Inc.

Effect of Pre-Irradiation Annealing and Laser Modification on the Formation of Radiation-Induced Surface Color Centers in Lithium Fluoride

NASA Astrophysics Data System (ADS)

Voitovich, A. P.; Kalinov, V. S.; Novikov, A. N.; Radkevich, A. V.; Runets, L. P.; Stupak, A. P.; Tarasenko, N. V.

2017-01-01

It is shown that surface color centers of the same type are formed in the surface layer and in regions with damaged crystal structure inside crystalline lithium fluoride after γ-irradiation. Results are presented from a study of the effect of pre-irradiation annealing on the efficiency with which surface centers are formed in lithium fluoride nanocrystals. Raising the temperature for pre-irradiation annealing from room temperature to 250°C leads to a substantial reduction in the efficiency with which these centers are created. Surface color centers are not detected after γ-irradiation for pre-irradiation annealing temperatures of 300°C and above. Adsorption of atmospheric gases on the crystal surface cannot be regarded as a necessary condition for the formation of radiation-induced surface centers.

Biocontamination and particulate detection system

NASA Technical Reports Server (NTRS)

Jacobs, J. M. (Inventor)

1979-01-01

A method for determining the characteristics and amount of microscopic contaminants lodged on a photographed surface is disclosed. An image enhanced full color photographic negative and print are taken of the contaminated surface. Three black and white prints are developed subsequently from red, green and blue separation filter overlays of the color negative. Both the color and three monochromatic prints are then scanned to extract in digital form a profile of any contaminant possibly existing on the surface. The resulting profiles are electronically analyzed and compared with data already stored relating to known contaminants.

Polarization and Color Filtering Applied to Enhance Photogrammetric Measurements of Reflective Surfaces

NASA Technical Reports Server (NTRS)

Wells, Jeffrey M.; Jones, Thomas W.; Danehy, Paul M.

2005-01-01

Techniques for enhancing photogrammetric measurement of reflective surfaces by reducing noise were developed utilizing principles of light polarization. Signal selectivity with polarized light was also compared to signal selectivity using chromatic filters. Combining principles of linear cross polarization and color selectivity enhanced signal-to-noise ratios by as much as 800 fold. More typical improvements with combining polarization and color selectivity were about 100 fold. We review polarization-based techniques and present experimental results comparing the performance of traditional retroreflective targeting materials, cornercube targets returning depolarized light, and color selectivity.

Influence of Mechanical and Chemical Degradation in the Surface Roughness, Gloss, and Color of Microhybrid Composites.

PubMed

Lemos, Cleidiel Aa; Mauro, Silvio J; Dos Santos, Paulo H; Briso, Andre Lf; Fagundes, Ticiane C

2017-04-01

The aim of this study was to investigate the association of different degradations on the roughness, gloss, and color changes of microhybrid composites. Ten specimens were prepared for Charisma, Amelogen Plus, Point 4, and Opallis resins. Surfaces were polished and baseline measurements of roughness, gloss, and color were recorded. Specimens were then submitted to chemical and mechanical challenges, and the specimens were reevaluated. Roughness and gloss were analyzed by Kruskal -Wallis and Dunn's test (p < 0.05). Color change (ΔE) was analyzed by one-way analysis of variance and Tukey's tests (p < 0.05). The initial and final data were compared using the Wilcoxon test (p < 0.05). Spearman test checked the correlation between the roughness and gloss (p < 0.05). Regarding surface roughness and gloss, there was no difference between composites before challenges. However, all composites showed a significant increase of roughness after challenges, with highest values for Charisma. The gloss was influenced by challenges, evidencing the best gloss for Point 4. Charisma showed the highest value of color change. There was no correlation between surface roughness and gloss for the initial analysis, and after the challenges. Composites were influenced by association of challenges, and Charisma showed the highest changes for roughness, gloss, and color. The type of composite resin influenced the properties of materials, which are surface roughness, gloss, and color change. The dentist should be aware of the performance of different brands, to choose the correct required composite resin for each type of patient or region to be restored.

Colors Of Liquid Crystals Used To Measure Surface Shear Stresses

NASA Technical Reports Server (NTRS)

Reda, D. C.; Muratore, J. J., Jr.

1996-01-01

Developmental method of mapping shear stresses on aerodynamic surfaces involves observation, at multiple viewing angles, of colors of liquid-crystal surface coats illuminated by white light. Report describing method referenced in "Liquid Crystals Indicate Directions Of Surface Shear Stresses" (ARC-13379). Resulting maps of surface shear stresses contain valuable data on magnitudes and directions of skin friction forces associated with surface flows; data used to refine mathematical models of aerodynamics for research and design purposes.

The Global Color of Pluto from New Horizons

NASA Astrophysics Data System (ADS)

Olkin, Catherine B.; Spencer, John R.; Grundy, William M.; Parker, Alex H.; Beyer, Ross A.; Schenk, Paul M.; Howett, Carly J. A.; Stern, S. Alan; Reuter, Dennis C.; Weaver, Harold A.; Young, Leslie A.; Ennico, Kimberly; Binzel, Richard P.; Buie, Marc W.; Cook, Jason C.; Cruikshank, Dale P.; Dalle Ore, Cristina M.; Earle, Alissa M.; Jennings, Donald E.; Singer, Kelsi N.; Linscott, Ivan E.; Lunsford, Allen W.; Protopapa, Silvia; Schmitt, Bernard; Weigle, Eddie; the New Horizons Science Team

2017-12-01

The New Horizons flyby provided the first high-resolution color maps of Pluto. We present here, for the first time, an analysis of the color of the entire sunlit surface of Pluto and the first quantitative analysis of color and elevation on the encounter hemisphere. These maps show the color variation across the surface from the very red terrain in the equatorial region, to the more neutral colors of the volatile ices in Sputnik Planitia, the blue terrain of East Tombaugh Regio, and the yellow hue on Pluto’s North Pole. There are two distinct color mixing lines in the color-color diagrams derived from images of Pluto. Both mixing lines have an apparent starting point in common: the relatively neutral-color volatile-ice covered terrain. One line extends to the dark red terrain exemplified by Cthulhu Regio and the other extends to the yellow hue in the northern latitudes. There is a latitudinal dependence of the predominant color mixing line with the most red terrain located near the equator, less red distributed at mid-latitudes and more neutral terrain at the North Pole. This is consistent with the seasonal cycle controlling the distribution of colors on Pluto. Additionally, the red color is consistent with tholins. The yellow terrain (in the false color images) located at the northern latitudes occurs at higher elevations.

75 FR 31663 - Sweet Cherries Grown in Designated Counties in Washington; Change in the Handling Regulation

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-04

... that a premium packed cherry must meet. In addition, to help stabilize the negative pricing pressure... cherries and other lightly-colored sweet cherry varieties that are designated as ``premium'' when handled... lightly-colored sweet cherry varieties that are designated as ``premium'' when marketed. Under this...

A Human Bird Eye View of Mars

NASA Image and Video Library

2016-09-08

There have been several proposals to send people to Mars but not land them on the surface. Instead, they would either fly by Mars once and return to Earth, or orbit Mars for a period of time. Would they at least get spectacular naked-eye views of the Martian surface? Some parts of Mars would be interesting: for example the polar ice caps, and the bright (dust-covered) regions would be seen reasonably well, although the color is very uniform. The dark (low reflectance) regions of Mars are some of the most interesting and important regions studied by our orbiters and rovers, but they would appear very bland to humans outside of the planet's atmosphere. This is because the thin atmosphere of Mars is quite bright and dusty, so when looking at dark surface areas, most of what you would see is scattered light from the atmospheric dust, and the surface would have a very low contrast. It would also appear reddish, even if the surface materials are not reddish, from the scattered light. Here is an example from the Nili Patera region of Mars, a candidate future landing site. At the top is an approximation of the natural color as seen by people with normal color vision -- almost no surface detail is visible. In the middle is the standard HiRISE IRB color product, consisting of the infrared, red, and blue-green images displayed as red, green, and blue, respectively, and with a min-max stretch applied to each color. In other words, the darkest pixel in the entire image is set to black, the brightest pixel is set to white, and all others are linearly interpolated. At bottom is an enhanced color product, in which each bandpass is given a linear stretch for the local subimage, sometimes saturating a small percentage of data to black or white to give the rest of the scene more contrast, followed by color saturation enhancement. Now we can see a diversity of colors that distinguish different surface units: dust, sand, and rocks with different minerals. http://photojournal.jpl.nasa.gov/catalog/PIA21040

Antioxidative activities of mushroom (Flammulina velutipes) extract added to bigeye tuna meat: dose-dependent efficacy and comparison with other biological antioxidants.

PubMed

Bao, H N D; Ushio, H; Ohshima, T

2009-03-01

The ability of a hydrophilic extract prepared from edible mushroom (Flammulina velutipes) to stabilize fresh color of bigeye tuna (Thunnus obesus) meat was evaluated to compare it with certain other antioxidants. The fresh color shelf life of bigeye tuna meats, to which were added as 1, 3, or 5 mL of mushroom extract to 100 g of minced bigeye tuna meat, prolonged duration of ice storage by more than 2, 4, and 6 d, respectively, in comparison with the control tuna meat without mushroom extract. The addition of 5 mL of mushroom extract to 100 g of minced bigeye tuna meat was more effective than adding ascorbic acid sodium salt (500 ppm) or alpha-tocopherol (500 ppm) with regard to oxidation of lipid in the tuna meat. The color changes significantly correlated with lipid oxidation as well as metmyoglobin formation in the tuna meat. These results clearly show that the mushroom extract is a potential antioxidant, which has the ability to stabilize fresh color of tuna meat during ice storage.

Storage length, storage temperature, and lean formulation influence the shelf-life and stability of traditionally packaged ground beef.

PubMed

Martin, J N; Brooks, J C; Brooks, T A; Legako, J F; Starkey, J D; Jackson, S P; Miller, M F

2013-11-01

The effect of storage length and temperature on the shelf life of three ground beef formulations (lean:fat: 73:27, 81:19 and 91:9) was investigated. Coarsely ground beef was stored at -1.7 or 2.3°C for up to 28d. Traditional overwrap packages were produced every 7d prior to retail display for 24h. Lipid oxidation (TBARS), subjective color, instrumental color, and aerobic bacteria were evaluated after 0 and 24h of display. Formulation influenced initial L* and subjective color values (P<0.05). Storage temperature did not affect initial color, but product stored at 2.3°C was more discolored after 24h (P<0.05). Aerobic bacteria increased as storage d and temperature increased (P<0.05). Initial TBARS increased through d 21, but were lower after 28d. Overall, initial characteristics depended on formulation; however, ground beef shelf-life and stability were largely influenced by storage length and storage temperature. Copyright © 2013 Elsevier Ltd. All rights reserved.

[Effects of colorants on yttria stabilized tetragonal zirconia polycrystals powder].

PubMed

Wang, Bo; Chen, Jianfeng; Zhang, Yanchun; Wang, Ru

2015-10-01

To evaluate the effect of Fe2O3 and CeO2 as colorants on yttria stabilized tetragonal zirconia poly-crystals (Y-TZP) powder. The spray granulation slurry of colored zirconia was prepared with different concentrations of Fe2O3 (0.15%) and CeO2 (4%), which were added in Y-TZP. Zirconia powder was made by spray granulation. The powder specimens were divided into three groups: uncolored zirconia, Fe2O3 (0.15%) zirconia, and CeO2 (4%) zirconia. The particle morphologies of the powder specimens were measured with a laser particle size analyzer and an optical microscope. The differences in D50 among the three groups were statistically significant (P<0.05). Group Fe2O3 showed a significant difference from groups CeO2 and uncolored zirconia (P<0.05). Group uncolored zirconia showed no significant difference from group CeO2 (P>0.05). Mostly spherical powder was observed in the three groups. Fe2O3 as a colorant can affect particles, whereas CeO2 has no effect.

Is the U-B color sufficient for identifying water of hydration on solar system bodies?

NASA Technical Reports Server (NTRS)

Vilas, Faith

1995-01-01

The U-B color has been suggested as a predictor of the presence of water of hydration on asteroids. Photometry from the Eight-Color Asteroid Survey (ECAS) was used to test this concept. An overlap in U-B color prevents this magnitude difference from distinguishing between surface material that was thermally processed at higher temperatures and surface material that was aqueously altered. Two tests of the presence of water of hydration using visible spectral region photometry failed to flag those few higher albedo M- and E-class asteroids having photometry that shows a 3.0-micrometers water of hydration absorption. These asteroids probably contain little or no oxidized iron in their surface material.

Color stability of pigmented maxillofacial silicone elastomer: effects of nano-oxides as opacifiers.

PubMed

Han, Ying; Zhao, Yimin; Xie, Chao; Powers, John M; Kiat-amnuay, Sudarat

2010-01-01

This study evaluated the effects of nano-oxides on the color stability of pigmented silicone A-2186 maxillofacial prosthetic elastomers before and after artificial aging. Each of three widely used UV-shielding nano-sized particle oxides (TiO(2), ZnO, CeO(2)), based on recent survey of the industry at 1%, 2%, 2.5% concentrations were combined with each of five intrinsic silicone pigment types (no pigments, red, yellow, blue, and a mixture of the three pigments). Silicone A-2186 without nano-oxides or pigments served as control, for a total of 46 experimental groups of elastomers. In each group of the study, all specimens were aged in an artificial aging chamber for an energy exposure of 450kJ/m(2). CIE L*a*b* values were measured by a spectrophotometer. The 50:50% perceptibility (ΔE*=1.1) and acceptability threshold (ΔE*=3.0) were used in interpretation of recorded color differences. Color differences after aging were subjected to three-way analysis of variance. Means were compared by Fisher's PLSD intervals at the 0.05 level of significance. Yellow pigments mixed with all three nano-oxides at all intervals increased ΔE* values significantly from 3.7 up to 8.4. When mixed pigment groups were considered, TiO(2) at 2%, and 2.5% exhibited the smallest color changes, followed by ZnO and CeO(2), respectively (p<0.001). At 1%, CeO(2) exhibited the smallest color changes, followed by TiO(2) and ZnO, respectively (p<0.001). The smallest color differences, observed for nano-oxides groups, were recorded for CeO(2) at 1%, and TiO(2) at 2% and 2.5%. When the nano-oxides were tested at all concentrations, CeO(2) groups overall had the most color changes, and TiO(2) groups had the least. All ΔE* values of the mixed pigment groups were below the 50:50% acceptability threshold (ΔE*=1.2-2.3, below 3.0) except 2% CeO(2) (ΔE*=4.2). 1% nano-CeO(2) and 2% and 2.5% nano-TiO(2) used as opacifiers for silicone A-2186 maxillofacial prostheses with mixed pigments exhibited the least color changes when subjected to artificial aging at 450kJ/m(2). Yellow silicone pigment mixed with all three nano-oxides significantly affected color stability of A-2186 silicone elastomer. Copyright © 2010 Elsevier Ltd. All rights reserved.

7 CFR 51.892 - Color terms.

Code of Federal Regulations, 2013 CFR

2013-01-01

... characteristic color means at least two-thirds of the surface of the berry is light red through dark red color... dark red and for the Cardinal variety light pink through purple color shall be permitted. [36 FR 9126... 7 Agriculture 2 2013-01-01 2013-01-01 false Color terms. 51.892 Section 51.892 Agriculture...

7 CFR 51.892 - Color terms.

Code of Federal Regulations, 2014 CFR

2014-01-01

... characteristic color means at least two-thirds of the surface of the berry is light red through dark red color... dark red and for the Cardinal variety light pink through purple color shall be permitted. [36 FR 9126... 7 Agriculture 2 2014-01-01 2014-01-01 false Color terms. 51.892 Section 51.892 Agriculture...

7 CFR 51.892 - Color terms.

Code of Federal Regulations, 2011 CFR

2011-01-01

... color means at least two-thirds of the surface of the berry is light red through dark red color; except... for the Cardinal variety light pink through purple color shall be permitted. [36 FR 9126, May 20, 1971... 7 Agriculture 2 2011-01-01 2011-01-01 false Color terms. 51.892 Section 51.892 Agriculture...

7 CFR 51.892 - Color terms.

Code of Federal Regulations, 2012 CFR

2012-01-01

... color means at least two-thirds of the surface of the berry is light red through dark red color; except... for the Cardinal variety light pink through purple color shall be permitted. [36 FR 9126, May 20, 1971... 7 Agriculture 2 2012-01-01 2012-01-01 false Color terms. 51.892 Section 51.892 Agriculture...

Automatic Color Sorting System for Hardwood Edge-Glued Panel Parts

Treesearch

Richard W. Conners; D.Earl Kline; Philip A. Araman

1996-01-01

The color sorting of edge-glued panel parts is becoming more important in the manufacture of hardwood products. Consumers, while admiring the natural appearance of hardwoods, do not like excessive color variation across product surfaces. Color uniformity is particularly important today because of the popularity of lightly stained products. Unfortunately, color sorting...

The effects of surface gloss and roughness on color constancy for real 3-D objects.

PubMed

Granzier, Jeroen J M; Vergne, Romain; Gegenfurtner, Karl R

2014-02-21

Color constancy denotes the phenomenon that the appearance of an object remains fairly stable under changes in illumination and background color. Most of what we know about color constancy comes from experiments using flat, matte surfaces placed on a single plane under diffuse illumination simulated on a computer monitor. Here we investigate whether material properties (glossiness and roughness) have an effect on color constancy for real objects. Subjects matched the color and brightness of cylinders (painted red, green, or blue) illuminated by simulated daylight (D65) or by a reddish light with a Munsell color book illuminated by a tungsten lamp. The cylinders were either glossy or matte and either smooth or rough. The object was placed in front of a black background or a colored checkerboard. We found that color constancy was significantly higher for the glossy objects compared to the matte objects, and higher for the smooth objects compared to the rough objects. This was independent of the background. We conclude that material properties like glossiness and roughness can have significant effects on color constancy.

Effective method for detecting regions of given colors and the features of the region surfaces

NASA Astrophysics Data System (ADS)

Gong, Yihong; Zhang, HongJiang

1994-03-01

Color can be used as a very important cue for image recognition. In industrial and commercial areas, color is widely used as a trademark or identifying feature in objects, such as packaged goods, advertising signs, etc. In image database systems, one may retrieve an image of interest by specifying prominent colors and their locations in the image (image retrieval by contents). These facts enable us to detect or identify a target object using colors. However, this task depends mainly on how effectively we can identify a color and detect regions of the given color under possibly non-uniform illumination conditions such as shade, highlight, and strong contrast. In this paper, we present an effective method to detect regions matching given colors, along with the features of the region surfaces. We adopt the HVC color coordinates in the method because of its ability of completely separating the luminant and chromatic components of colors. Three basis functions functionally serving as the low-pass, high-pass, and band-pass filters, respectively, are introduced.

The Barnes-Evans color-surface brightness relation: A preliminary theoretical interpretation

NASA Technical Reports Server (NTRS)

Shipman, H. L.

1980-01-01

Model atmosphere calculations are used to assess whether an empirically derived relation between V-R and surface brightness is independent of a variety of stellar paramters, including surface gravity. This relationship is used in a variety of applications, including the determination of the distances of Cepheid variables using a method based on the Beade-Wesselink method. It is concluded that the use of a main sequence relation between V-R color and surface brightness in determining radii of giant stars is subject to systematic errors that are smaller than 10% in the determination of a radius or distance for temperature cooler than 12,000 K. The error in white dwarf radii determined from a main sequence color surface brightness relation is roughly 10%.

Silicon nanoparticle-ZnS nanophosphors for ultraviolet-based white light emitting diode

NASA Astrophysics Data System (ADS)

Stupca, Matthew; Nayfeh, Osama M.; Hoang, Tuan; Nayfeh, Munir H.; Alhreish, Bahjat; Boparai, Jack; AlDwayyan, Abdullah; AlSalhi, Mohamad

2012-10-01

Present red phosphor converters provide spectra dominated by sharp lines and suffer from availability and stability issues which are not ideal for color mixing in display or solid state lighting applications. We examine the use of mono dispersed 3 nm silicon nanoparticles, with inhomogeneously broadened red luminescence as an effective substitute for red phosphors. We tested a 3-phase hybrid nanophosphor consisting of ZnS:Ag, ZnS:Cu,Au,Al, and nanoparticles. Correlated color temperature is examined under UV and LED pumping in the range 254, 365-400 nm. The temperature is found reasonably flat for the longer wavelengths and drops for the shorter wavelengths while the color rendering index increases. The photo stability of the phosphors relative to the silicon nanoparticles is recorded. The variation in the temperature is analyzed in terms of the strength of inter-band-gap transition and continuum band to band transitions.

Improved color stability of white organic light-emitting diodes without interlayer between red, orange and blue emission layers

NASA Astrophysics Data System (ADS)

Xue, Kaiwen; Chen, Ping; Duan, Yu; Sheng, Ren; Han, Guangguang; Zhao, Yi

2016-03-01

We demonstrated color stability improved white phosphorescent organic light-emitting diodes (WOLEDs) based on red, orange and blue emission layers. Iridium(III) Bis(3,5-diflouro)-2-(2-pyridyl)phenyl-(2-carboxypyridyl) was doped into red emission layer (R-EML) and orange emission layer (O-EML) to lower the electrons injection barrier and facilitate the ambipolar charge carriers balance. Consequently, the recombination region was extended to the R-EML and O-EML, leading to the excellently stable spectra and the reduction of triplet-triplet annihilation. Then the resulting device with a negligible Commission International de L'Eclairage coordinates shift of (0.003, 0.007) within a wide luminance range as well as a high color rendering index of 90 was gained, which was comparable to the profit caused by the conventional method of introducing the interlayer. And the emission mechanism of the WOLEDs was also discussed.

The effect of CMC and arabic gum stabilizer combination on the characteristics of soursop velva (Annona muricata L.)

NASA Astrophysics Data System (ADS)

Parnanto, N. H. R.; Yudhistira, B.; Pertiwi, S. R.; Pangestika, A.

2018-03-01

The aims of this study were to determine the effect of the combination of CMC and Arabic Gum stabilizer toward the soursop velva characteristics and to determine the best stabilizer combination of soursop velva. This study was performed using Completely Randomized Design (CRD) with one factor: combination of CMC and Arabic Gum stabilizer using two sample replications and the analysis was repeated three times. The result showed that the use of the combination of CMC and Arabic Gum stabilizer gave a significant effect on the overrun value, melting power, total dissolved solids, moisture content, dietary fiber, taste, texture and overalls. Moreover, there were no significant effect on color and flavor of the soursop velva. The experiment showed that soursop velva F4 (3:1) was the best formula with overrun value 9.93%, the melting power was 22 minutes 52 seconds, the total dissolved solids 19,10°Brix, the moisture content 71.508%, dietary fiber 3.301% and it has sensory values of color, taste, flavor, texture, overall at 3.66, 3.267, 3.33, 4.06, 3.10 respectively.

A Few Simple Questions about Colour in Art and Science.

ERIC Educational Resources Information Center

Harris, John

1999-01-01

Presents scientific explanations of primary colors and color mixing, black and white surfaces, the spectrum and the ability of the eye to distinguish color difference, the description of color, and the appearance and optical properties of metals. Contains 16 references. (Author)

Devices based on surface plasmon interference filters

NASA Technical Reports Server (NTRS)

Wang, Yu (Inventor)

2001-01-01

Devices based on surface plasmon filters having at least one metal-dielectric interface to support surface plasmon waves. A multi-layer-coupled surface plasmon notch filter is provided to have more than two symmetric metal-dielectric interfaces coupled with one another to produce a transmission spectral window with desired spectral profile and bandwidth. Such notch filters can form various color filtering devices for color flat panel displays.

Design and construction of hierarchical TiO2 nanorod arrays by combining layer-by-layer and hydrothermal crystallization techniques for electrochromic application

NASA Astrophysics Data System (ADS)

Chen, Yongbo; Li, Xiaomin; Bi, Zhijie; He, Xiaoli; Li, Guanjie; Xu, Xiaoke; Gao, Xiangdong

2018-05-01

The hierarchical TiO2 (H-TiO2) nanorod arrays (NRAs) composed of single-crystalline nanorods and nanocrystals were finely designed and successfully constructed for electrochromic (EC) application. By combining layer-by-layer (LBL) method and hydrothermal crystallization technique, the superfine nanocrystals (5-7 nm), which can provide abundant active sites and facilitate ion insertion/extraction during EC reactions, were uniformly and conformally assembled on the surface of single-crystalline TiO2 (SC-TiO2) NRAs. The as-formed H-TiO2 NRAs integrate the advantages of one-dimensional NRAs with fast kinetics and superfine nanocrystals with high ion capacity, showing highly enhanced EC performance. Large optical contrast (40.3%), shorter coloring/bleaching time (22/4 s), high coloration efficiency (11.2 cm2 C-1), and excellent cycling stability can be achieved in H-TiO2 NRAs, superior to the pristine SC-TiO2 NRAs and nanocrystalline TiO2 films. This work provides a feasible and well-designed strategy to explore high-performance materials for EC application.

Effects of illumination and packaging on non-heme iron and color attributes of sliced ham.

PubMed

Li, H; Li, C B; Xu, X L; Zhou, G H

2012-08-01

This study was designed to investigate effects of illumination and packaging on color of cooked cured sliced ham during refrigeration, and the possibility of decomposition of nitrosylheme under light and oxygen exposure. Three illumination levels and three packaging films with different oxygen transmission rates (OTRs) were used in two separate experiments during 35 days storage, and pH value, a* value, nitrosylheme, residual nitrite and non-heme iron were evaluated. Packaging OTRs had significant effects (P<0.01) on a* value, but illumination level and packaging OTR did not affect (P>0.05) nitrosylheme concentration during storage. For both groups, storage time had a significant effect (P<0.01) on a* value and nitrosylheme. Negative relationships between nitrosylheme and nitrite in the illumination group, and between nitrosylheme and non-heme iron in the packaging group were observed. Therefore, illumination level and packaging OTR had limited effects on overall pigment stability, but more discoloration and loss of redness occurred on the surface of products. Copyright © 2012 Elsevier Ltd. All rights reserved.

A novel colorimetric triple-helix molecular switch aptasensor for ultrasensitive detection of tetracycline.

PubMed

Ramezani, Mohammad; Mohammad Danesh, Noor; Lavaee, Parirokh; Abnous, Khalil; Mohammad Taghdisi, Seyed

2015-08-15

Detection methods of antibiotic residues in blood serum and animal derived foods are of great interest. In this study a colorimetric aptasensor was designed for sensitive, selective and fast detection of tetracycline based on triple-helix molecular switch (THMS) and gold nanoparticles (AuNPs). As a biosensor, THMS shows distinct advantages including high stability, sensitivity and preserving the selectivity and affinity of the original aptamer. In the absence of tetracycline, THMS is stable, leading to the aggregation of AuNPs by salt and an obvious color change from red to blue. In the presence of tetracycline, aptamer binds to its target, signal transduction probe (STP) leaves the THMS and adsorbs on the surface of AuNPs. So the well-dispersed AuNPs remain stable against salt-induced aggregation with a red color. The presented aptasensor showed high selectivity toward tetracyclines with a limit of detection as low as 266 pM for tetracycline. The designed aptasensor was successfully applied to detect tetracycline in serum and milk. Copyright © 2015 Elsevier B.V. All rights reserved.

Effects of surface-finishing protocols on the roughness, color change, and translucency of different ceramic systems.

PubMed

Akar, Gülcan Coşkun; Pekkan, Gürel; Çal, Ebru; Eskitaşçıoğlu, Gürcan; Özcan, Mutlu

2014-08-01

Surface-finishing protocols have a mechanical impact on ceramic surfaces that could eventually affect surface topography and light scattering. An optimum protocol is needed to avoid damaging the optical properties of ceramics. The purpose of this study was to determine the effects of different surface-finishing protocols on the surface roughness, color change, and translucency of ceramic and metal ceramic restorations. Standardized disk-shaped specimens (1.5 × 10 mm, n=128) were fabricated from 3 different ceramic core materials (aluminum oxide [Al2O3]-AL, zirconium oxide [ZrO2]-ZR, lithium disilicate [Li2Si2O5]-LIT), veneered (V) with dentin ceramics (n=32 per group), and placed in the following groups: ALV, ZRV, and LITV. The metal ceramic group acted as the control (n=32). Four different surface-finishing methods were tested. Airborne-particle abrasion with 50 μm Al2O3, polishing with adjustment kit, polishing with adjustment kit plus diamond polishing paste, and autoglazing (n=8 subgroup) were applied on the veneering ceramics. The specimens were analyzed with a profilometer for surface roughness, and color change and translucency were measured with a clinical spectrophotometer. Statistical analyses were performed with 1-way ANOVA and the Tukey honest significant difference tests (α=.05). Specimens treated with the airborne particle abrasion method showed significantly higher mean profilometer for surface roughness values in all groups (P<.05). The polishing with adjustment kit and autoglazing methods revealed statistically similar surface roughness values in all groups (P>.05). With the diamond polishing paste method, lower surface roughness values were achieved in the ZRV and metal ceramic groups acted as the control groups. Different surface-finishing methods affected the color change of the ceramic systems, except for ZRV. Surface-finishing protocols significantly affected the translucency values of the ALV, LITV, and metal ceramic groups (P<.05). No single surface-finishing protocol can be recommended to obtain the smoothest surface and the least color change without affecting translucency for the ceramics tested. The airborne-particle abrasion protocol created rougher surfaces and decreased translucency, and color change in zirconia was not affected by the finishing protocols. Copyright © 2014 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Color stability of restorative materials in response to Arabic coffee, Turkish coffee and Nescafe.

PubMed

Al-Samadani, Khalid H

2013-07-01

To evaluate the effect of Arabic coffee, Turkish coffee and Nescafe on the color stability of four different composite resins after a period of aging time 1, 7 and 30 days. Twenty specimens from each type of tested composite resin material were prepared. Five specimens from each tested material (Z350 XT, Artist, GC and Z250) was evaluated after storage in Arabic coffee, Turkish coffee, Nescafe and distil water (control) at 37°C in a dark container for 1, 7 and 30 days. Color measurement was done using colorimeter based on the CIE L* a* b* color scale. Color differences ΔE*ab, Δb* and Δa* among specimens immersed in distil water and staining coffee beverages were evaluated overtime. Mean values were statistically analyzed with one-way analysis of variance (ANOVA), followed by Tukey test with p < 0.05 as significance level. All tested composite resins showed increase color change after a period of 1, 7 and 30 days. The color change ΔE*ab , Δb* and Δa* exhibited by Arabic coffee, in Turkish coffee and Nescafe except Δa*. The highest total color difference ΔE*ab after 30 days was in group A Arabic coffee (ΔE > 1.5 perceivable) and not perceivable in group B Turkish coffee and group C Nescafe. For Δb* all materials discolored toward yellowness after 30 days except Arabic coffee group which shifted from yellowness toward blueness (Δb*> 1.5 perceivable). The effect of staining beverages on the resin composite materials increases with time of aging toward yellowness and not perceivable in all groups except with Arabic coffee which had highest effect after 30 days and the discoloration shifted from yellowness to blueness perceivable.

The effect of different drinks on the color stability of different restorative materials after one month.

PubMed

Tekçe, Neslihan; Tuncer, Safa; Demirci, Mustafa; Serim, Merve Efe; Baydemir, Canan

2015-11-01

The aim of this study was to evaluate the effect of three different drinks on the color parameters of four different restorative materials. Three different composites (Filtek Ultimate Universal Restorative, Filtek Ultimate Flowable, and Filtek Silorane, 3M ESPE) and a polyacid-modified composite resin material (Dyract XP, Dentsply DeTrey GmbH) were evaluated. Eighty-four disc-shaped specimens of 8 mm in diameter and 2 mm in thickness were prepared (n = 21 each). Color coordinates (L*a*b*, ΔL*, Δa*, Δb*, and ΔE*) were measured using a VİTA Easyshade Compact (VİTA Zahnfabrik) after 24 hr of storage (baseline) and after 30 day of storage in three different beverages of black tea, Coca cola, or water (control) (n = 7). In each beverage, the specimens were stored three times a day, one hr each, for 30 day. The color changes (ΔE) were calculated and were analyzed by Kruskal-Wallis and Dunn multiple comparison test. The color difference (ΔE*) of the resin materials ranged between 1.31 and 15.28 after 30 day of immersion in the staining solutions. Dyract XP in Coca cola (15.28 ± 2.61) and black tea (12.22 ± 2.73) showed the highest mean ΔE* value after 30 day, followed by Filtek Ultimate Universal Restorative (5.99 ± 1.25) and Filtek Ultimate Flowable (4.71 ± 1.40) in black tea (p < 0.05). The compomers displayed unacceptable color changes at the end of 30 day in all beverages. Among resin composites, the silorane based composite exhibited relatively good color stability than the others. Filtek Ultimate Universal Restorative and Filtek Flowable showed similar color changes in all beverages.

Non-crosslinking gold nanoprobe-LAMP for simple, colorimetric, and specific detection of Salmonella typhi

NASA Astrophysics Data System (ADS)

Bozorgmehr, Ali; Yazdanparast, Razieh; Mollasalehi, Hamidreza

2016-12-01

In this study, we developed a non-crosslinking gold nanoprobe loop-mediated isothermal amplification (LAMP) method for nanodiagnosis of bacterial typhoid fever source, Salmonella typhi. Therefore, a unique region in the S. typhi genomic DNA was targeted for LAMP amplification using a specific set of four precisely designed primers. Also, for specific colorimetric visualization of the amplicons, a thiolated oligonucleotide probe, complementary to the single-stranded loop region of the amplicons between F2 and F1C segments, was designed. The probe was bound to the surface of gold nanoparticles via covalent bonds. Increasing the salt concentration in the detection reaction medium led to aggregation of nanoprobes in the blank and the negative vessels in a time-dependent form. That was followed by a change in the surface plasmon resonance (SPR) leading to blue/black color that was observable by the naked eyes after about 5 min. Meanwhile, the original pink/red color was retained in the positive sample due to the large interparticle spaces and the stability against the ionic strength elevation which persisted for about 30 min. The whole process of DNA extraction, amplification, and detection took less than 2 h with a sensitivity of 20 CFU/ml. The developed gold nanoprobe-LAMP could serve as a simple, rapid, and cost-effective method for nanodiagnosis of S. typhi in point-of-need applications.

Rapid solid-state metathesis route to transition-metal doped titanias

DOE Office of Scientific and Technical Information (OSTI.GOV)

Coleman, Nathaniel; Perera, Sujith; Gillan, Edward G., E-mail: edward-gillan@uiowa.edu

2015-12-15

Rapid solid-state metathesis (SSM) reactions are often short-lived highly exothermic reactions that yield a molten alkali halide salt that aids in product growth and crystallization. SSM reactions may also produce kinetically stabilized structures due to the short (seconds) reaction times. This report describes the investigation of rapid SSM reactions in the synthesis of transition-metal doped titanias (M–TiO{sub 2}). The dopant targeted compositions were ten mol percent and based on elemental analysis, many of the M–TiO{sub 2} samples were close to this targeted level. Based on surface analysis, some samples showed large enrichment in surface dopant content, particularly chromium and manganesemore » doped samples. Due to the highly exothermic nature of these reactions, rutile structured TiO{sub 2} was observed in all cases. The M–TiO{sub 2} samples are visible colored and show magnetic and optical properties consistent with the dopant in an oxide environment. UV and visible photocatalytic experiments with these visibly colored rutile M–TiO{sub 2} powders showed that many of them are strongly absorbent for methylene blue dye and degrade the dye under both UV and visible light illumination. This work may open up SSM reactions as an alternate non-thermodynamic reaction strategy for dopant incorporation into a wide range of oxide and non-oxides.« less

Detailed electromagnetic simulation for the structural color of butterfly wings.

PubMed

Lee, R Todd; Smith, Glenn S

2009-07-20

Many species of butterflies exhibit interesting optical phenomena due to structural color. The physical reason for this color is subwavelength features on the surface of a single scale. The exposed surface of a scale is covered with a ridge structure. The fully three-dimensional, periodic, finite-difference time-domain method is used to create a detailed electromagnetic model of a generic ridge. A novel method for presenting the three-dimensional observed color pattern is developed. Using these tools, the change in color that is a result of varying individual features of the scale is explored. Computational models are developed that are similar to three butterflies: Morpho rhetenor, Troides magellanus, and Ancyluris meliboeus.

The co-pigmentation of anthocyanin isolated from mangosteen pericarp (Garcinia Mangostana L.) as Natural Dye for Dye- Sensitized Solar Cells (DSSC)

NASA Astrophysics Data System (ADS)

Munawaroh, H.; adillah, G. F.; Saputri, L. N. M. Z.; Hanif, Q. A.; Hidayat, R.; Wahyuningsih, S.

2016-02-01

Study of color stability of anthocyanin from extract mangosteen pericarp (Garcinia mangostana L.) with co-pigmentation method has been conducted. Malic acid and ascorbic acid used as a co-pigment to stabilize the anthocyanin structure through formation of new binding between anthocyanin. Anthocyanin from mangosteen pericarp were isolated by several steps, including maceration, extraction, and Thin Layer Chromatography (TLC). The anthocyanin separation was conducted by TLC, while the identification of functional groups of those compound, were used FTIR (Fourier Transform Infrared Spectroscopy) for spectra analysis. Ultraviolet- visible absorption spectra have represented differences absorbance and color intensity in various pH. Copigmentation with malic acid and ascorbic acid in many composition and temperature were also well described. Meanwhile, anthocyanin-malic acid and anthocyanin-ascorbic acid have color retention higher than that of pure anthocyanin. Maximum color retention has been achieved at a ratio of 1:3 and 1:5 for ascorbic acid and malic acid, respectively. Therefore, the addition of ascorbic acid and malic acid as a copigment shows the ability to protect color retention of anthocyanin (mangosteen pericarp) from degradation process. The better efficiency of DSSC (η) have been achieved, whereas n of controlled anthocyanin, anthocyanin-ascorbic acid, and anthocyanin-malic acid were 0,1996%, 0,2922%, 0,3029%, respectively.

On the mechanism of chromophototherapy used in sports medicine and rehabilitation

NASA Astrophysics Data System (ADS)

Tang, Mian; Liu, Timon C.

2005-01-01

Light is the primary stimulus for regulating circadian rhythms, seasonal cycles, and neuroendocrine responses in many species, including humans. The major circadian pacemaker in the hypothalamic suprachiasmatic nucleus is entrained to the light/dark cycles from the outside world by circadian photoreceptors which are functionally characterized by the direct sensitivity to light with broad spectrum and the relatively high stability. Chromophototherapy mediated by the color indirect effect (CIE), the physiological and psychological effects of color resulting from color vision, is functionally characterized by the sensitivity to light with narrow spectrum and the relatively low stability. In this paper, the mechanism of chromophototherapy used in sports medicine and rehabilitation, especially in treating overtraining syndrome (OTS), was discussed. Although several hypotheses and the corresponding OTS treatments have been proposed, each only explains and treats a selective aspect of OTS. On the one hand, an autonomic or neuroendocrine imbalance is hypothesized as underlying by Lehmann et al so that the described functional alterations of pituitary-adrenal axis and sympathetic system can explain persistent performance incompetence in affected athletes beside additional mechanisms. On the other hand, cold color (green, blue or violet) excites parasympathetic subsystem and hot color (red, orange or yellow) excites sympathetic subsystem for chromophototherapy. The conclusion was then drawn that chromophototherapy might be a good therapy to treat OTS.

Photometric Separation of Stellar Properties Using SDSS Filters

NASA Astrophysics Data System (ADS)

Lenz, Dawn D.; Newberg, Jo; Rosner, Robert; Richards, Gordon T.; Stoughton, Chris

1998-12-01

Using synthetic photometry of Kurucz model spectra, we explore the colors of stars as a function of temperature, metallicity, and surface gravity with Sloan Digital Sky Survey (SDSS) filters, u'g'r'i'z'. The synthetic colors show qualitative agreement with the few published observations in these filters. We find that the locus of synthetic stars is basically two-dimensional for 4500 < T < 8000 K, which precludes simultaneous color separation of the three basic stellar characteristics we consider. Colors including u' contain the most information about normal stellar properties; measurements in this filter are also important for selecting white dwarfs. We identify two different subsets of the locus in which the loci separate by either metallicity or surface gravity. For 0.5 < g' - r' < 0.8 (corresponding roughly to G stars), the locus separates by metallicity; for photometric error of a few percent, we estimate metallicity to within ~0.5 dex in this range. In the range -0.15 < g' - r' < 0.00 (corresponding roughly to A stars), the locus shows separation by surface gravity. In both cases, we show that it is advantageous to use more than two colors when determining stellar properties by color. Strategic observations in SDSS filters are required to resolve the source of a ~5% discrepancy between synthetic colors of Gunn-Stryker stars, Kurucz models, and external determinations of the metallicities and surface gravities. The synthetic star colors can be used to investigate the properties of any normal star and to construct analytic expressions for the photometric prediction of stellar properties in special cases.

Comparative evaluation of effects of bleaching on color stability and marginal adaptation of discolored direct and indirect composite laminate veneers under in vivo conditions.

PubMed

Jain, Veena; Das, Taposh K; Pruthi, Gunjan; Shah, Naseem; Rajendiran, Suresh

2015-01-01

Change in color and loss of marginal adaptation of tooth colored restorative materials is not acceptable. Bleaching is commonly used for treating discolored teeth. However, the literature is scanty regarding its effect on color and marginal adaptation of direct and indirect composite laminate veneers (CLVs) under in vivo conditions. Purpose of the study was to determine the effect of bleaching on color change and marginal adaptation of direct and indirect CLVs over a period of time when exposed to the oral environment. For this purpose, a total of 14 subjects irrespective of age and sex indicated for CLV restorations on maxillary anterior teeth were selected following the inclusion and exclusion criteria. For each subject, indirect CLVs were fabricated and looted in the first quadrant (Group 1) and direct CLV's (Group 2), were given in the second quadrant. Color change was assessed clinically using intra-oral digital spectrophotometer and marginal adaptation was assessed on epoxy resin replica of the tooth-restoration interface under scanning electron microscope. After 6 months, the subjects underwent a home bleaching regimen for 14 days using 10% carbamide peroxide. The assessment of color change and marginal adaptation was done at 6 months after veneering (0-180 days), immediately after the bleaching regimen (0-194 days) and 3 months after the bleaching regimen (0-284 days). The difference in median color change (ΔE) between the groups was tested using Wilcoxon rank sum test while the median color change with time within the groups was tested using Wilcoxon signed rank test. The difference in the rates of marginal adaptation was tested between the groups using Chi-square/Fisher's exact test. Bleaching led to statistically significant color change at cervical (CE), middle and incisal (IE) regions when direct and indirect composites were compared (P < 0.05). During intra-group comparison, direct CLV's showed significant color change at CE and IE regions when ΔE was compared at 180 days and 284 days (CE 10 vs. CE 30, P = 0.008, IE 10 vs. IE 30, P = 0.003). No significant differences were found when within group comparison was made for indirect laminates. Intergroup comparison between the groups showed significant difference in marginal adaptation at CE margin at all.time points (at baseline, P = 0.005; at 180 days, P = 0.007; 194 days, P = 0.025; at 284 days, P = 0.067). After bleaching, indirect CLVs performed better in terms of color stability whereas direct CLVs performed better in terms of marginal adaptation. Indirect composites should be preferred to direct composites as veneering materials as they have better color stability. Special attention should be given to their marginal adaptation especially in the CE region. Bleaching should be avoided in patients with composite restorations in the mouth.

Quality characteristics, structural changes, and storage stability of semi-dried noodles induced by moderate dehydration: understanding the quality changes in semi-dried noodles.

PubMed

Li, Man; Zhu, Ke-Xue; Sun, Qing-Jie; Amza, Tidjani; Guo, Xiao-Na; Zhou, Hui-Ming

2016-03-01

Based on the critical water content (for noodle deterioration) concluded previously, high-temperature-short-time (HTST; 105-135°C) and medium-temperature-long-time (MTLT; 45-75°C) dehydrations were introduced in this study to produce semi-dried noodles. The effects of HTST and MTLT on the quality parameters of semi-dried noodles, as well as noodle structure, storage stability, and changes in starch and protein components were thoroughly investigated. Differential scanning calorimeter (DSC) and birefringent analysis presented few starch gelatinization (approximately 30%) in HTST dehydrated noodles. Scanning electron microscopy (SEM) images showed more compact noodle surface, with uniform pores in the cross section, probably due to enhanced protein-starch combination after HTST dehydration. Meanwhile, HTST induced protein polymerizations in semi-dried noodles, mainly by -SH-S-S interchange, and resulted in significantly (P<0.05) reduced cooking loss. Furthermore, HTST noodles showed higher microbial and color stability. Shelf-life of dehydrated samples at 120°C was extended to 5days from 1day of the control. Copyright © 2015 Elsevier Ltd. All rights reserved.

Outer Space Research Helps Color Habitability in Earth Interiors

NASA Technical Reports Server (NTRS)

Haines, Richard F.

1977-01-01

Color is one of the most important elements in making an environment habitable. Both color and light level combine to create comfortable and efficient work areas and satisfying leisure time environments. Indeed, without light, color cannot even be experienced. It is vitally important for the designer to understand the subject of habitability and to know how to make a positive impact upon the habitability of spaces through the application of proven principles of color-design developed by the scientific community. Consider some of these possibilities and pitfalls: A color chosen in broad daylight will not appear the same under dim lighting conditions. If a designer were creating a dimly lit cocktail lounge, for example, there is little sense in using dark colors, which also tend to be more expensive. When the eyes have dark-adapted for even five minutes, any color reflecting 20 percent or less will appear black, and the color experience will be lost. Therefore, surface reflectances should be kept at least above 20 to 25 percent to maintain color where illumination is at low levels. In effect, for lower reflectance surfaces, higher levels of illumination are required to produce the most accurate color discriminability.

Thermal stability of liquid antioxidative extracts from pomegranate peel

USDA-ARS?s Scientific Manuscript database

This research was carried out to assess the potential of using the natural antioxidants in pomegranate peel extracts as replacement for synthetic antioxidants. As a result the thermal stability of pomegranate peel extract products during sterilization and storage, and its effect on industrial, color...

Thermal and storage characteristics of tomato seed oil

USDA-ARS?s Scientific Manuscript database

Thermal oxidative stability and effect of different storage conditions on quality characteristics of tomato seed oil have not been studied. The objectives of this research were to determine the changes in quality and oxidative stability of tomato seed oil, including color, antioxidant activity, per...

Effect of opacifiers and UV absorbers on pigmented maxillofacial silicone elastomer, part 1: color stability after artificial aging.

PubMed

Han, Ying; Powers, John M; Kiat-Amnuay, Sudarat

2013-06-01

Much dissatisfaction with the color instability and reduced lifetime of extraoral maxillofacial prostheses due to degradation has been reported. The purpose of this study was to compare the effect of a UV mineral-based light protecting agent (LP) on the color stability of pigmented maxillofacial silicone elastomer MDX-4210/Type A after artificial aging to 2 widely used opacifiers. Forty-five groups were established (n=225 total). Three different types of opacifiers (LP, titanium white dry pigment [TW], or silicone intrinsic white [SW]) were added to silicone MDX-4210/type A at 3 concentrations (5%, 10%, or 15%) and subsequently combined with each of 5 colors (no pigments [control], red, blue, yellow, or mixed pigments). Artists' oil pigment was used with LP and TW, while intrinsic silicone pigment was used to color SW. Before and after an energy exposure of 450 kJ/m(2), CIE L*a*b* values were measured with a spectrophotometer. The CIELAB 50:50% perceptibility (ΔE*=1.1) and acceptability threshold (ΔE*=3.0) were used to interpret color changes (ΔE*). Color differences after aging were subjected to 3-way ANOVA. Means were compared by the Fisher PLSD intervals at α=.05. The ΔE* values of all groups were below the acceptability threshold of ΔE*=3.0, except for the control group of SW at 10%, which showed the greatest color change (ΔE*=3.1). When mixed pigment groups were considered, at 5% concentration, LP showed the smallest color change, followed by SW and TW (P<.05); at 10%, no significant differences among the 3 opacifiers were noted (P>.05); at 15%, LP showed the smallest color change, followed by TW and SW (P<.05). All 3 opacifiers at all concentrations protected pigmented silicone MDX4-4210/Type A from color degradation. The LP group showed the smallest color changes. Copyright © 2013 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

Alumina/polymer-coated nanocrystals with extremely high stability used as a color conversion material in LEDs

NASA Astrophysics Data System (ADS)

Woo, Ju Yeon; Lee, Jongsoo; Han, Chang-Soo

2013-12-01

The long-term stability of quantum dot (QD)-based devices under harsh environmental conditions has been a critical bottleneck to be resolved for commercial use. Here, we demonstrate an extremely stable QD/alumina/polymer hybrid structure by combining internal atomic layer deposition (ALD) infilling with polymer encapsulation. ALD infilling and polymer encapsulation of QDs synergistically prohibit the degradation of QDs in terms of optical, thermal and humid attacks. Our hybrid QD/alumina/polymer film structure showed no noticeable reduction in photoluminescence even in a commercial grade test (85% humidity at 85 ° C) over 28 days. In addition, we successfully fabricated a QD-based light-emitting device with excellent long-term stability by incorporating hybrid QD/alumina/polymer film as a color conversion material on light-emitting diode chips.

A Closer Look at Telesto False-Color

NASA Image and Video Library

2006-02-08

These views show surface features and color variation on the Trojan moon Telesto. The smooth surface of this moon suggests that, like Pandora, it is covered with a mantle of fine, dust-sized icy material. The monochrome image was taken in visible light (see PIA07696). To create the false-color view, ultraviolet, green and infrared images were combined into a single black and white picture that isolates and maps regional color differences. This "color map" was then superposed over a clear-filter image. The origin of the color differences is not yet understood, but may be caused by subtle differences in the surface composition or the sizes of grains making up the icy soil. Tiny Telesto is a mere 24 kilometers (15 miles) wide. The image was acquired with the Cassini spacecraft narrow-angle camera on Dec. 25, 2005 at a distance of approximately 20,000 kilometers (12,000 miles) from Telesto and at a Sun-Telesto-spacecraft, or phase, angle of 58 degrees. Image scale is 118 meters (387 feet) per pixel. http://photojournal.jpl.nasa.gov/catalog/PIA07697

Accurate color synthesis of three-dimensional objects in an image

NASA Astrophysics Data System (ADS)

Xin, John H.; Shen, Hui-Liang

2004-05-01

Our study deals with color synthesis of a three-dimensional object in an image; i.e., given a single image, a target color can be accurately mapped onto the object such that the color appearance of the synthesized object closely resembles that of the actual one. As it is almost impossible to acquire the complete geometric description of the surfaces of an object in an image, this study attempted to recover the implicit description of geometry for the color synthesis. The description was obtained from either a series of spectral reflectances or the RGB signals at different surface positions on the basis of the dichromatic reflection model. The experimental results showed that this implicit image-based representation is related to the object geometry and is sufficient for accurate color synthesis of three-dimensional objects in an image. The method established is applicable to the color synthesis of both rigid and deformable objects and should contribute to color fidelity in virtual design, manufacturing, and retailing.

Surface color perception under two illuminants: the second illuminant reduces color constancy

NASA Technical Reports Server (NTRS)

Yang, Joong Nam; Shevell, Steven K.

2003-01-01

This study investigates color perception in a scene with two different illuminants. The two illuminants, in opposite corners, simultaneously shine on a (simulated) scene with an opaque dividing wall, which controls how much of the scene is illuminated by each source. In the first experiment, the height of the dividing wall was varied. This changed the amount of each illuminant reaching objects on the opposite side of the wall. Results showed that the degree of color constancy decreased when a region on one side of the wall had cues to both illuminants, suggesting that cues from the second illuminant are detrimental to color constancy. In a later experiment, color constancy was found to improve when the specular highlight cues from the second illuminant were altered to be consistent with the first illuminant. This corroborates the influence of specular highlights in surface color perception, and suggests that the reduced color constancy in the first experiment is due to the inconsistent, though physically correct, cues from the two illuminants.

7 CFR 51.647 - Slightly colored.

Code of Federal Regulations, 2010 CFR

2010-01-01

... FRESH FRUITS, VEGETABLES AND OTHER PRODUCTS 1,2 (INSPECTION, CERTIFICATION, AND STANDARDS) United States... aggregate of green color, the portion of the fruit surface which is not discolored shows some yellow color. ...

Surfactant-free carnauba wax dispersion and its use for layer-by-layer assembled protective surface coatings on wood

NASA Astrophysics Data System (ADS)

Lozhechnikova, Alina; Bellanger, Hervé; Michen, Benjamin; Burgert, Ingo; Österberg, Monika

2017-02-01

Protection from liquid water and UV radiation are equally important, and a sophisticated approach is needed when developing surface coatings that preserve the natural and well-appreciated aesthetic appearance of wood. In order to prevent degradation and prolong the service life of timber, a protective coating was assembled using carnauba wax particles and zinc oxide nanoparticles via layer-by-layer deposition in water. For this purpose, a facile sonication route was developed to produce aqueous wax dispersion without any surfactants or stabilizers. The suspension was stable above pH 4 due to the electrostatic repulsion between the negatively charged wax particles. The particle size could be controlled by the initial wax concentration with average particle sizes ranging from 260 to 360 nm for 1 and 10 g/L, respectively. The deposition of wax particles onto the surface of spruce wood introduced additional roughness to the wood surface at micron level, while zinc oxide provided nano roughness and UV-absorbing properties. In addition to making wood superhydrophobic, this novel multilayer coating enhanced the natural moisture buffering capability of spruce. Moreover, wood surfaces prepared in this fashion showed a significant reduction in color change after exposure to UV light. A degradation of the wax through photocatalytic activity of the ZnO particles was measured by FTIR, indicating that further studies are required to achieve long-term stability. Nevertheless, the developed coating showed a unique combination of superhydrophobicity and excellent moisture buffering ability and some UV protection, all achieved using an environmentally friendly coating process, which is beneficial to retain the natural appearance of wood and improve indoor air quality and comfort.

VIIRS On-Orbit Calibration for Ocean Color Data Processing

NASA Technical Reports Server (NTRS)

Eplee, Robert E., Jr.; Turpie, Kevin R.; Fireman, Gwyn F.; Meister, Gerhard; Stone, Thomas C.; Patt, Frederick S.; Franz, Bryan; Bailey, Sean W.; Robinson, Wayne D.; McClain, Charles R.

2012-01-01

The NASA VIIRS Ocean Science Team (VOST) has the task of evaluating Suomi NPP VIIRS ocean color data for the continuity of the NASA ocean color climate data records. The generation of science quality ocean color data products requires an instrument calibration that is stable over time. Since the VIIRS NIR Degradation Anomaly directly impacts the bands used for atmospheric correction of the ocean color data (Bands M6 and M7), the VOST has adapted the VIIRS on-orbit calibration approach to meet the ocean science requirements. The solar diffuser calibration time series and the solar diffuser stability monitor time series have been used to derive changes in the instrument response and diffuser reflectance over time for bands M1-M11.

Rupture of vertical soap films

NASA Astrophysics Data System (ADS)

Rio, Emmanuelle

2014-11-01

Soap films are ephemeral and fragile objects. They tend to thin under gravity, which gives rise to the fascinating variations of colors at their interfaces but leads systematically to rupture. Even a child can create, manipulate and admire soap films and bubbles. Nevertheless, the reason why it suddenly bursts remains a mystery although the soap chosen to stabilize the film as well as the humidity of the air seem very important. One difficulty to study the rupture of vertical soap films is to control the initial solution. To avoid this problem we choose to study the rupture during the generation of the film at a controlled velocity. We have built an experiment, in which we measure the maximum length of the film together with its lifetime. The generation of the film is due to the presence of a gradient of surface concentration of surfactants at the liquid/air interface. This leads to a Marangoni force directed toward the top of the film. The film is expected to burst only when its weight is not balanced anymore by this force. We will show that this leads to the surprising result that the thicker films have shorter lifetimes than the thinner ones. It is thus the ability of the interface to sustain a surface concentration gradient of surfactants which controls its stability.

Activity study of biogenic spherical silver nanoparticles towards microbes and oxidants

NASA Astrophysics Data System (ADS)

Hoskote Anand, Kiran Kumar; Mandal, Badal Kumar

2015-01-01

The eco-friendly approach for the green synthesis of silver nanoparticles (SNP) using Terminalia bellirica (T. bellirica) fruit extract is reported herein. Initially formation of SNP was noticed through visual color change from yellow to reddish brown and further analyzed by surface plasmonic resonance (SPR) band at 429 nm using UV-Vis spectroscopy. Identification of different polyphenols present in T. bellirica extract was done using High Pressure Liquid Chromatography (HPLC). Aqueous T. bellirica extract contains high amount of gallic acid which is major secondary metabolite responsible for the reduction and stabilization process. It was established by analyses of extracts before and after reduction using HPLC. Formation of spherical SNP was characterized by Transmission Electron Microscopy (TEM) analysis. X-ray Diffraction (XRD) study revealed crystalline nature of SNP. Presence of different functional groups on the surface of SNP was evidenced by Fourier Transform Infrared Spectroscopy (FTIR) study. A plausible mechanism of reduction and stabilization processes involved in the synthesis of stable SNP was also explained based on HPLC and FTIR data. In addition, the synthesized SNP was tested for antibacterial and antioxidant activities. SNP showed good antimicrobial activity against both gram positive (S. aureus) and gram negative (E. coli) bacteria. It also showed good antioxidant activity compared to ascorbic acid as standard antioxidant by using standard DPPH method.

Sea Surface Temperature and Ocean Color Variability in the South China Sea

NASA Astrophysics Data System (ADS)

Conaty, A. P.

2001-12-01

The South China Sea is a marginal sea in the Southeast Asian region whose surface circulation is driven by monsoons and whose surface currents have complex seasonal patterns. Its rich natural resources and strategic location have made its small islands areas of political dispute among the neighboring nations. This study aims to show the seasonal and interannual variability of sea surface temperature and ocean color in South China Sea. It makes use of NOAA's Advanced Very High Resolution Radiometer (AVHRR) satellite data sets on sea surface temperature for the period 1981-2000 and NASA's Nimbus-7 Coastal Zone Color Scanner (CZCS) and Sea-viewing Wide Field-of-view Sensor (SeaWiFS) satellite data sets on pigment concentration (ocean color) for the period 1981-1996 and 1997-2000, respectively. Transect lines were drawn along several potential hotspot areas to show the variability in sea surface temperature and pigment concentration through time. In-situ data on sea surface temperature along South China Sea were likewise plotted to see the variability with time. Higher seasonal variability in sea surface temperature was seen at higher latitudes. Interannual variability was within 1-3 Kelvin. In most areas, pigment concentration was higher during northern hemisphere winter and autumn, after the monsoon rains, with a maximum of 30 milligrams per cubic meter.

Can whitening toothpastes maintain the optical stability of enamel over time?

PubMed Central

da Silva, Eduardo Moreira; Maia, Juliana Nunes da Silva Meirelles Dória; Mitraud, Carine Gnatiuk; Russo, Juliana do Espírito Santo; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

2018-01-01

Abstract Besides the effects on the health of individuals, cigarette smoking can also interfere with the appearance of their teeth. Objective To evaluate the effect of cigarette smoking-toothbrushing-cycling (CSTC) with whitening toothpastes on the roughness and optical behavior of bovine enamel for eight weeks. Material and Methods Thirty bovine dentin/enamel discs, 8.0 mm in diameter and 2.0 mm thick, were randomly divided into three groups according to the toothpastes: whitening (Colgate Luminous White - CW and Oral B 3D White - OW), and a non-whitening (Colgate - C). The roughness, color (CIE L*a*b* system), translucency and gloss were measured before and after the specimens were submitted to CSTC. The topography of the specimens was analyzed by scanning electron microscopy. During the first week, the specimens were daily subjected to the consumption of 20 cigarettes and brushed (40 strokes/100 g) with the toothpastes' slurries. Thereafter, the CSTC was weekly applied in an accumulated model (140 cigarettes/280 strokes) for seven weeks. The data were submitted to two-way ANOVA, Tukey's HSD test, and paired-t test (α=0.05). Results The three toothpastes produced significant changes in roughness, color, translucency and gloss (p<0.05). After eight weeks, the roughness and the gloss produced by the three toothpastes were similar (p>0.05), while OW produced the lowest color change and the translucency of C was lower than that of CW (p<0.05). The three toothpastes produced a significant decrease in L* values and a significant increase in a* values after eight weeks (p<0.05). No significant difference in the b* coordinate was found for OW (p=0.13) There were topographic changes in the enamel surfaces. Conclusions The whitening toothpastes increased the roughness, changed the topography and were not able to maintain the optical stability of enamel exposed over eight weeks. PMID:29412362

Can whitening toothpastes maintain the optical stability of enamel over time?

PubMed

Silva, Eduardo Moreira da; Maia, Juliana Nunes da Silva Meirelles Dória; Mitraud, Carine Gnatiuk; Russo, Juliana do Espírito Santo; Poskus, Laiza Tatiana; Guimarães, José Guilherme Antunes

2018-02-01

Besides the effects on the health of individuals, cigarette smoking can also interfere with the appearance of their teeth. To evaluate the effect of cigarette smoking-toothbrushing-cycling (CSTC) with whitening toothpastes on the roughness and optical behavior of bovine enamel for eight weeks. Thirty bovine dentin/enamel discs, 8.0 mm in diameter and 2.0 mm thick, were randomly divided into three groups according to the toothpastes: whitening (Colgate Luminous White - CW and Oral B 3D White - OW), and a non-whitening (Colgate - C). The roughness, color (CIE L*a*b* system), translucency and gloss were measured before and after the specimens were submitted to CSTC. The topography of the specimens was analyzed by scanning electron microscopy. During the first week, the specimens were daily subjected to the consumption of 20 cigarettes and brushed (40 strokes/100 g) with the toothpastes' slurries. Thereafter, the CSTC was weekly applied in an accumulated model (140 cigarettes/280 strokes) for seven weeks. The data were submitted to two-way ANOVA, Tukey's HSD test, and paired-t test (α=0.05). The three toothpastes produced significant changes in roughness, color, translucency and gloss (p<0.05). After eight weeks, the roughness and the gloss produced by the three toothpastes were similar (p>0.05), while OW produced the lowest color change and the translucency of C was lower than that of CW (p<0.05). The three toothpastes produced a significant decrease in L* values and a significant increase in a* values after eight weeks (p<0.05). No significant difference in the b* coordinate was found for OW (p=0.13) There were topographic changes in the enamel surfaces. The whitening toothpastes increased the roughness, changed the topography and were not able to maintain the optical stability of enamel exposed over eight weeks.

The color metamerism evaluation of paint based on ocean spectrum

NASA Astrophysics Data System (ADS)

Chen, Zhongwei; Huang, Hao; Liao, Ningfang

2018-03-01

The surface color of the sea is affected by many factors and will be different the due to the material difference in the sea. And the difference will be reflected in the ocean spectrum. If the paint materials of a ship can simulate the ocean surface color and the ocean spectrum at the same time. This will minimize the metamerism. In this paper, the method of metamerism is used to evaluate paint based on ocean spectrum, so that the color of the material affected by the light source will be reflected in the metamerism index.

Recalibrated mariner 10 color mosaics: Implications for mercurian volcanism

USGS Publications Warehouse

Robinson, M.S.; Lucey, P.G.

1997-01-01

Recalibration of Mariner 10 color image data allows the identification of distinct color units on the mercurian surface. We analyze these data in terms of opaque mineral abundance, iron content, and soil maturity and find color units consistent with the presence of volcanic deposits on Mercury's surface. Additionally, materials associated with some impact craters have been excavated from a layer interpreted to be deficient in opaque minerals within the crust, possibly analogous to the lunar anorthosite crust. These observations suggest that Mercury has undergone complex differentiation like the other terrestrial planets and the Earth's moon.

AFM imaging of natural optical structures

NASA Astrophysics Data System (ADS)

Dallaeva, Dinara; Tománek, Pavel; Prokopyeva, Elena; Kaspar, Pavel; Grmela, Lubomír.; Škarvada, Pavel

2015-01-01

The colors of some living organisms assosiated with the surface structure. Irridesence butterfly wings is an example of such coloration. Optical effects such as interference, diffraction, polarization are responsible for physical colors appearance. Alongside with amazing beauty this structure represent interest for design of optical devices. Here we report the results of morphology investigation by atomic force microscopy. The difference in surface structure of black and blue wings areas is clearly observed. It explains the angle dependence of the wing blue color, since these micrometer and sub-micrometer quasiperiodical structures could control the light propagation, absorption and reflection.

Influence of Hemostatic Solution on Bond Strength and Physicochemical Properties of Resin Cement.

PubMed

Araújo, Isabela Sousa de; Prado, Célio Jesus do; Raposo, Luís Henrique Araújo; Soares, Carlos José; Zanatta, Rayssa Ferreira; Torres, Carlos Rocha Gomes; Ruggiero, Reinaldo; Silva, Gisele Rodrigues da

2017-01-01

The aim of this study was to evaluate the degree of conversion, color stability, chemical composition, and bond strength of a light-cured resin cement contaminated with three different hemostatic solutions. Specimens were prepared for the control (uncontaminated resin cement) and experimental groups (resin cement contaminated with one of the hemostatic solutions) according to the tests. For degree of conversion, DC (n = 5) and color analyses (n = 10), specimens (3 mm in diameter and 2 mm thick) were evaluated by Fourier transform infrared spectroscopy (FTIR) and CIELAB spectrophotometry (L*, a*, b*), respectively. For elemental chemical analysis (n = 1), specimens (2 mm thick and 6 mm in diameter) were evaluated by x-ray energy-dispersive spectroscopy (EDS). The bond strengths of the groups were assessed by the microshear test (n = 20) in a leucite-reinforced glass ceramic substrate, followed by failure mode analysis by scanning electron microscopy (SEM). The mean values, except for the elemental chemical evaluation and failure mode, were evaluated by ANOVA and Tukey's HSD test. The color stability was influenced by storage time (p<0.001) and interaction between contamination and storage time (p<0.001). Hemostop and Viscostat Clear contamination did not affect the DC, however Viscostat increased the DC. Bond strength of the resin cement to ceramic was negatively affected by the contaminants (p<0.001). Contamination by hemostatic agents affected the bond strength, degree of conversion, and color stability of the light-cured resin cement tested.

7 CFR 51.1830 - Fairly well colored.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Fairly well colored. 51.1830 Section 51.1830 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Definitions § 51.1830 Fairly well colored. Fairly well colored means that the surface of the fruit may have...

7 CFR 51.1533 - Well colored.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Well colored. 51.1533 Section 51.1533 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Well colored. “Well colored,” as applied to Italian type prunes, means that 95 percent of the surface...

7 CFR 51.1533 - Well colored.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Well colored. 51.1533 Section 51.1533 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing... Well colored. “Well colored,” as applied to Italian type prunes, means that 95 percent of the surface...

7 CFR 51.1830 - Fairly well colored.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Fairly well colored. 51.1830 Section 51.1830 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... Definitions § 51.1830 Fairly well colored. Fairly well colored means that the surface of the fruit may have...

Synthesis and optical properties modulation of ZnO/Eu2O3 nanocable arrays

NASA Astrophysics Data System (ADS)

Yang, Lei; She, Yajuan; Zhao, Shihua; Yue, Shihai; Wang, Qian; Hu, Aiping; Zhang, Wei

2010-11-01

White-light-emitting materials have attracted considerable attention because of their applications, such as large-surface emitting devices and displays. However, simply mixing nanoparticles would result in uneven color. Nanocables are expected to improve the chemical stability and color uniformity. Herein we demonstrate the synthesis of Eu2O3/ZnO nanocable arrays embedded in anodic alumina template via a versatile, simple, and cheap method. In order to control the composition of the cable with low cost, a two-step synthesis including an electric field deposition and a sol-gel template approach is used to fabricate the nanocable. The product is investigated by x-ray powder diffraction, transmission electron microscopy, selected area electron diffraction, and photoluminescence (PL) spectrum. The results show that ordered Eu2O3/ZnO nanocable arrays with an average inside diameter of 20-40 nm and wall thickness of 20-40 nm were prepared. By adjusting the excitation wavelength, change of the emitting color of the cables from blue to white could be obtained. Energy and charge transfer were found by investigating the electronic transition and recombination in the PL process. These arrays are promising for applications in display, white phosphors, and ultraviolet detectors owing to the special optical properties. And this method may be of much significance in the synthesis of nanocables with the controllable composition.

Microbial, Physicochemical, and Sensory Characteristics of Quality Grade 2 Beef Enhanced by Injection of Pineapple Concentrate and Honey

PubMed Central

Yoon, Ji Won; Lee, Da Gyeom; Lee, Hyun Jung; Choe, Juhui; Jung, Samooel; Jo, Cheorun

2017-01-01

This study investigated the effect of injecting pineapple concentrate and honey into low marbled beef in order to enhance its sensory qualities, particularly tenderness and flavor, without compromising its fresh appearance. Beef loin was injected with a solution of 6.0% pineapple concentrate, 2.5% honey, 0.5% monosodium L-glutamate, 0.5% phosphate, and 0.3% salt (w/w) to 120% (w/w) of initial meat weight and stored for 14 d. Non-injected beef loin served as a control. Total aerobic bacterial counts, surface meat color, shear force, reducing sugar content, and sensory evaluation of the beef were analyzed at 0.5, 7, and 14 d of storage. Injection did not affect the total aerobic bacterial counts or color of the beef. However, injection increased the stability of meat color, compared with that of the control, during storage. The shear force value was significantly lower in the injected beef than that in the control. The injected beef had a significantly higher reducing sugar content compared with that of the control. In sensory evaluation, tenderness, juiciness, flavor, and overall acceptance of the injected beef were significantly higher than those of the control at 0.5 d. In conclusion, injection of pineapple concentrate and honey can improve the sensory qualities of low marbled beef, during short storage periods, without changing the fresh appearance of the beef. PMID:28943761

Securing Color Fidelity in 3D Architectural Heritage Scenarios.

PubMed

Gaiani, Marco; Apollonio, Fabrizio Ivan; Ballabeni, Andrea; Remondino, Fabio

2017-10-25

Ensuring color fidelity in image-based 3D modeling of heritage scenarios is nowadays still an open research matter. Image colors are important during the data processing as they affect algorithm outcomes, therefore their correct treatment, reduction and enhancement is fundamental. In this contribution, we present an automated solution developed to improve the radiometric quality of an image datasets and the performances of two main steps of the photogrammetric pipeline (camera orientation and dense image matching). The suggested solution aims to achieve a robust automatic color balance and exposure equalization, stability of the RGB-to-gray image conversion and faithful color appearance of a digitized artifact. The innovative aspects of the article are: complete automation, better color target detection, a MATLAB implementation of the ACR scripts created by Fraser and the use of a specific weighted polynomial regression. A series of tests are presented to demonstrate the efficiency of the developed methodology and to evaluate color accuracy ('color characterization').

Factors influencing internal color of cooked meats.

PubMed

Suman, Surendranath P; Nair, Mahesh N; Joseph, Poulson; Hunt, Melvin C

2016-10-01

This manuscript overviews the pertinent research on internal color of uncured cooked meats, biochemical processes involved in meat cookery, and fundamental mechanisms governing myoglobin thermal stability. Heat-induced denaturation of myoglobin, responsible for the characteristic dull-brown color of cooked meats, is influenced by a multitude of endogenous (i.e., pH, muscle source, species, redox state) and exogenous (i.e., packaging, ingredients, storage) factors. The interactions between these factors critically influence the internal cooked color and can confuse the consumers, who often perceive cooked color to be a reliable indicator for doneness and safety. While certain phenomena in cooked meat color are cosmetic in nature, others can mislead consumers and result in foodborne illnesses. Research in meat color suggests that processing technologies and cooking practices in industry as well as households influence the internal cooked color. Additionally, the guidelines of many international public health and regulatory authorities recommend using meat thermometers to determine safe cooking endpoint temperature and to ensure product safety. Copyright © 2016 Elsevier Ltd. All rights reserved.

Securing Color Fidelity in 3D Architectural Heritage Scenarios

PubMed Central

Apollonio, Fabrizio Ivan; Ballabeni, Andrea; Remondino, Fabio

2017-01-01

Ensuring color fidelity in image-based 3D modeling of heritage scenarios is nowadays still an open research matter. Image colors are important during the data processing as they affect algorithm outcomes, therefore their correct treatment, reduction and enhancement is fundamental. In this contribution, we present an automated solution developed to improve the radiometric quality of an image datasets and the performances of two main steps of the photogrammetric pipeline (camera orientation and dense image matching). The suggested solution aims to achieve a robust automatic color balance and exposure equalization, stability of the RGB-to-gray image conversion and faithful color appearance of a digitized artifact. The innovative aspects of the article are: complete automation, better color target detection, a MATLAB implementation of the ACR scripts created by Fraser and the use of a specific weighted polynomial regression. A series of tests are presented to demonstrate the efficiency of the developed methodology and to evaluate color accuracy (‘color characterization’). PMID:29068359

7 CFR 51.2652 - Fairly well colored.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 7 Agriculture 2 2013-01-01 2013-01-01 false Fairly well colored. 51.2652 Section 51.2652 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... § 51.2652 Fairly well colored. Fairly well colored means that at least 95 percent of the surface of the...

7 CFR 51.2652 - Fairly well colored.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 7 Agriculture 2 2014-01-01 2014-01-01 false Fairly well colored. 51.2652 Section 51.2652 Agriculture Regulations of the Department of Agriculture AGRICULTURAL MARKETING SERVICE (Standards... § 51.2652 Fairly well colored. Fairly well colored means that at least 95 percent of the surface of the...

7 CFR 51.2652 - Fairly well colored.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 7 Agriculture 2 2011-01-01 2011-01-01 false Fairly well colored. 51.2652 Section 51.2652... STANDARDS) United States Standards for Grades for Sweet Cherries 1 Definitions § 51.2652 Fairly well colored. Fairly well colored means that at least 95 percent of the surface of the cherry shows characteristic...

7 CFR 51.2652 - Fairly well colored.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 7 Agriculture 2 2010-01-01 2010-01-01 false Fairly well colored. 51.2652 Section 51.2652... STANDARDS) United States Standards for Grades for Sweet Cherries 1 Definitions § 51.2652 Fairly well colored. Fairly well colored means that at least 95 percent of the surface of the cherry shows characteristic...

Review of the CIE system of colorimetry and its use in dentistry.

PubMed

Westland, Stephen

2003-01-01

When we observe the light reflected from surfaces in a scene or look directly at light emitted by light sources, we experience the sensation of color. Color is just one attribute of a complex and not fully understood set of properties that define the appearance of our surroundings. To measure or specify the color of an object, we need to take into account the nature of the light under which the object is viewed, the spectral reflectance properties of the surface, and the properties of the human color vision system. In this article the CIE system of colorimetry is briefly reviewed and its limitations are described. The consequences of these limitations for color measurement in dentistry are discussed.

Color-tunable mixed photoluminescence emission from Alq3 organic layer in metal-Alq3-metal surface plasmon structure.

PubMed

Chen, Nai-Chuan; Liao, Chung-Chi; Chen, Cheng-Chang; Fan, Wan-Ting; Wu, Jin-Han; Li, Jung-Yu; Chen, Shih-Pu; Huang, Bohr-Ran; Lee, Li-Ling

2014-01-01

This work reports the color-tunable mixed photoluminescence (PL) emission from an Alq3 organic layer in an Au-Alq3-Au plasmonic structure through the combination of organic fluorescence emission and another form of emission that is enabled by the surface plasmons in the plasmonic structure. The emission wavelength of the latter depends on the Alq3 thickness and can be tuned within the Alq3 fluorescent spectra. Therefore, a two-color broadband, color-tunable mixed PL structure was obtained. Obvious changes in the Commission Internationale d'Eclairage (CIE) coordinates and the corresponding emission colors of Au-Alq3-Au samples clearly varied with the Alq3 thickness (90, 130, and 156 nm).

Color-tunable mixed photoluminescence emission from Alq3 organic layer in metal-Alq3-metal surface plasmon structure

PubMed Central

2014-01-01

This work reports the color-tunable mixed photoluminescence (PL) emission from an Alq3 organic layer in an Au-Alq3-Au plasmonic structure through the combination of organic fluorescence emission and another form of emission that is enabled by the surface plasmons in the plasmonic structure. The emission wavelength of the latter depends on the Alq3 thickness and can be tuned within the Alq3 fluorescent spectra. Therefore, a two-color broadband, color-tunable mixed PL structure was obtained. Obvious changes in the Commission Internationale d’Eclairage (CIE) coordinates and the corresponding emission colors of Au-Alq3-Au samples clearly varied with the Alq3 thickness (90, 130, and 156 nm). PMID:25328506

3D interferometric microscope: color visualization of engineered surfaces for industrial applications

NASA Astrophysics Data System (ADS)

Schmit, Joanna; Novak, Matt; Bui, Son

2015-09-01

3D microscopes based on white light interference (WLI) provide precise measurement for the topography of engineering surfaces. However, the display of an object in its true colors as observed under white illumination is often desired; this traditionally has presented a challenge for WLI-based microscopes. Such 3D color display is appealing to the eye and great for presentations, and also provides fast evaluation of certain characteristics like defects, delamination, or deposition of different materials. Determination of color as observed by interferometric objectives is not straightforward; we will present how color imaging capabilities similar to an ordinary microscope can be obtained in interference microscopes based on WLI and we will give measurement and imaging examples of a few industrial samples.

Method for measuring surface shear stress magnitude and direction using liquid crystal coatings

NASA Technical Reports Server (NTRS)

Reda, Daniel C. (Inventor)

1995-01-01

A method is provided for determining surface shear magnitude and direction at every point on a surface. The surface is covered with a shear stress sensitive liquid crystal coating and illuminated by white light from a normal direction. A video camera is positioned at an oblique angle above the surface to observe the color of the liquid crystal at that angle. The shear magnitude and direction are derived from the color information. A method of calibrating the device is also provided.

Velocity of action of oxygen, hydrogen sulfide, and halogens on metals

NASA Technical Reports Server (NTRS)

Tammann, Gustav; Koster, Werner

1952-01-01

This report discusses a method of determining the rate of surface oxidation of a metal by the change in the color of the surface film produced by reactions with oxygen, chlorine, or iodine. The metals studied included iron, nickel, copper, zinc, cadmium, tin, lead, cobalt, and manganese. Tables are given for surface film thickness versus color for various times.

Covalent immobilization of metal–organic frameworks onto the surface of nylon—a new approach to the functionalization and coloration of textiles

PubMed Central

Yu, Ming; Li, Wanxin; Wang, Ziqiang; Zhang, Bowu; Ma, Hongjuan; Li, Linfan; Li, Jingye

2016-01-01

The prevention of refractory organic pollution caused by conventional dyeing and the development of new fabrics with various functions are two issues to be solved urgently in the field of textile fabrication. Here, we report a new environmentally friendly route for the simultaneous coloration and functionalization of textiles by the covalent immobilization of a metal–organic framework, Cr-based MIL-101(Cr), onto the surfaces of nylon fabrics by co-graft polymerization with 2-hydroxyethyl acrylate initiated by γ-ray irradiation. The Cr(III) clusters color the nylon fabric, and the color intensity varies with the MIL-101 content, providing a “green” textile coloration method that is different from conventional dyeing processes. An X-ray diffraction (XRD) analysis shows that the nanoporous structure of the original MIL-101 particles is retained during radiation-induced graft polymerization. Numerous nanopores are introduced onto the surface of the nylon fabric, which demonstrated better sustained-release-of-aroma performance versus pristine nylon fabric in tests. The modified fabrics exhibit laundering durability, with MIL-101 nanoparticles intact on the nylon surface after 30 h of dry cleaning. PMID:26948405

Ganymede's Equatorial Region

NASA Technical Reports Server (NTRS)

1979-01-01

GANYMEDE COLOR PHOTOS: This color picture as acquired by Voyager 1 during its approach to Ganymede on Monday afternoon (the 5th of March). At ranges between about 230 to 250 thousand km. The images show detail on the surface with a resolution of four and a half km. This picture is south of PIA01516 (P21262) near the equator of Ganymede, and has relatively subdued colors in the visible part of the spectrum (later, scientists will analyze Voyager pictures taken in UV). The most striking features are the bright ray craters which have a distinctly 'bluer' color appearing white against the redder background. Ganymede's surface is known to contain large amounts of surface ice and it appears that these relatively young craters have spread bright fresh ice materials over the surface. Likewise, the lighter color and reflectivity of the grooved areas suggest that here, too, there is cleaner ice. We see ray craters with all sizes of ray patterns, ranging from extensive systems, down to craters which have only faint remnants of bright ejecta patterns. This variation suggests that, as on the Moon, there are processes which act to darken ray material, probably 'gardening' by micrometeoroid impact. JPL manages and controls the Voyager project for NASA's Office of Space Science.

Light reflected from colored mulches affects aroma and phenol content of sweet basil (Ocimum basilicum L.) leaves.

PubMed

Loughrin, J H; Kasperbauer, M J

2001-03-01

Basil (Ocimum basilicum L.) is an herb the leaves of which are used to add a distinct aroma and flavor to food. It was hypothesized that the size and chemical composition of sun-grown basil leaves could be influenced by the color of light reflected from the soil surface and by the action of the reflected light through the natural growth regulatory system within the growing plants. Leaf morphology, aroma compounds, and soluble phenolics were compared in basil that had been grown over six colors of polyethylene row covers. Altering the ratios of blue, red, and far-red light reflected to growing plants influenced both leaf morphology and chemistry. Leaves developing over red surfaces had greater area, moisture percentage (succulence), and fresh weight than those developing over black surfaces. Basil grown over yellow and green surfaces produced significantly higher concentrations of aroma compounds than did basil grown over white and blue covers. Leaves grown over yellow and green mulches also contained significantly higher concentrations of phenolics than those grown over the other colors. Clearly, the wavelengths (color) of light reflected to growing basil plants affected leaf size, aroma, and concentrations of soluble phenolics, some of which are antioxidants.

Asteroid age distributions determined by space weathering and collisional evolution models

NASA Astrophysics Data System (ADS)

Willman, Mark; Jedicke, Robert

2011-01-01

We provide evidence of consistency between the dynamical evolution of main belt asteroids and their color evolution due to space weathering. The dynamical age of an asteroid's surface (Bottke, W.F., Durda, D.D., Nesvorný, D., Jedicke, R., Morbidelli, A., Vokrouhlický, D., Levison, H. [2005]. Icarus 175 (1), 111-140; Nesvorný, D., Jedicke, R., Whiteley, R.J., Ivezić, Ž. [2005]. Icarus 173, 132-152) is the time since its last catastrophic disruption event which is a function of the object's diameter. The age of an S-complex asteroid's surface may also be determined from its color using a space weathering model (e.g. Willman, M., Jedicke, R., Moskovitz, N., Nesvorný, D., Vokrouhlický, D., Mothé-Diniz, T. [2010]. Icarus 208, 758-772; Jedicke, R., Nesvorný, D., Whiteley, R.J., Ivezić, Ž., Jurić, M. [2004]. Nature 429, 275-277; Willman, M., Jedicke, R., Nesvorny, D., Moskovitz, N., Ivezić, Ž., Fevig, R. [2008]. Icarus 195, 663-673. We used a sample of 95 S-complex asteroids from SMASS and obtained their absolute magnitudes and u, g, r, i, z filter magnitudes from SDSS. The absolute magnitudes yield a size-derived age distribution. The u, g, r, i, z filter magnitudes lead to the principal component color which yields a color-derived age distribution by inverting our color-age relationship, an enhanced version of the 'dual τ' space weathering model of Willman et al. (2010). We fit the size-age distribution to the enhanced dual τ model and found characteristic weathering and gardening times of τw = 2050 ± 80 Myr and τg=4400-500+700Myr respectively. The fit also suggests an initial principal component color of -0.05 ± 0.01 for fresh asteroid surface with a maximum possible change of the probable color due to weathering of Δ PC = 1.34 ± 0.04. Our predicted color of fresh asteroid surface matches the color of fresh ordinary chondritic surface of PC1 = 0.17 ± 0.39.

Mission to Earth: LANDSAT Views the World. [Color imagery of the earth's surface

NASA Technical Reports Server (NTRS)

Short, N. M.; Lowman, P. D., Jr.; Freden, S. C.; Finch, W. A., Jr.

1976-01-01

The LANDSAT program and system is described. The entire global land surface of Earth is visualized in 400 color plates at a scale and resolution that specify natural land cultural features in man's familiar environments. A glossary is included.

Inkjet printing of TiO2/AlOOH heterostructures for the formation of interference color images with high optical visibility

PubMed Central

Yakovlev, Aleksandr V.; Milichko, Valentin A.; Pidko, Evgeny A.; Vinogradov, Vladimir V.; Vinogradov, Alexandr V.

2016-01-01

This paper describes a practical approach for the fabrication of highly visible interference color images using sol-gel ink technique and a common desktop inkjet printer. We show the potential of titania-boehmite inks for the production of optical heterostructures on various surfaces, which after drying on air produce optical solid layers with low and high refractive index. The optical properties of the surface heterostructures were adjusted following the principles of antireflection coating resulting in the enhancement of the interference color optical visibility of the prints by as much as 32%. Finally, the presented technique was optimized following the insights into the mechanisms of the drop-surface interactions and the drop-on-surface coalescence to make it suitable for the production of even thickness coatings suitable for printing at a large scale. We propose that the technology described herein is a promising new green and sustainable approach for color printing. PMID:27848979

Research and Development of Large Area Color AC Plasma Displays

NASA Astrophysics Data System (ADS)

Shinoda, Tsutae

1998-10-01

Plasma display is essentially a gas discharge device using discharges in small cavities about 0. 1 m. The color plasma displays utilize the visible light from phosphors excited by the ultra-violet by discharge in contrast to monochrome plasma displays utilizing visible light directly from gas discharges. At the early stage of the color plasma display development, the degradation of the phosphors and unstable operating voltage prevented to realize a practical color plasma display. The introduction of the three-electrode surface-discharge technology opened the way to solve the problems. Two key technologies of a simple panel structure with a stripe rib and phosphor alignment and a full color image driving method with an address-and-display-period-separated sub-field method have realized practically available full color plasma displays. A full color plasma display has been firstly developed in 1992 with a 21-in.-diagonal PDP and then a 42-in.-diagonal PDP in 1995 Currently a 50-in.-diagonal color plasma display has been developed. The large area color plasma displays have already been put into the market and are creating new markets, such as a wall hanging TV and multimedia displays for advertisement, information, etc. This paper will show the history of the surface-discharge color plasma display technologies and current status of the color plasma display.

A novel experimental system of high stability and lifetime for the laser-desorption of biomolecules.

PubMed

Taherkhani, Mehran; Riese, Mikko; BenYezzar, Mohammed; Müller-Dethlefs, Klaus

2010-06-01

A novel laser desorption system, with improved signal stability and extraordinary long lifetime, is presented for the study of jet-cooled biomolecules in the gas phase using vibrationally resolved photoionization spectroscopy. As a test substance tryptophane is used to characterize this desorption source. A usable lifetime of above 1 month (for a laser desorption repetition rate of 20 Hz) has been observed by optimizing the pellets (graphite/tryptophane, 3 mm diameter and 6 mm length) from which the substance is laser-desorbed. Additionally, the stability and signal-to-noise ratio has been improved by averaging the signal over the entire sample pellet by synchronizing the data acquisition with the rotation of the sample rod. The results demonstrate how a combination of the above helps to produce stable and conclusive spectra of tryptophane using one-color and two-color resonant two-photon ionization studies.

Quantitative surface temperature measurement using two-color thermographic phosphors and video equipment

NASA Technical Reports Server (NTRS)

Buck, Gregory M. (Inventor)

1989-01-01

A thermal imaging system provides quantitative temperature information and is particularly useful in hypersonic wind tunnel applications. An object to be measured is prepared by coating with a two-color, ultraviolet-activated, thermographic phosphor. The colors emitted by the phosphor are detected by a conventional color video camera. A phosphor emitting blue and green light with a ratio that varies depending on temperature is used so that the intensity of light in the blue and green wavelengths detected by the blue and green tubes in the video camera can be compared. Signals representing the intensity of blue and green light at points on the surface of a model in a hypersonic wind tunnel are used to calculate a ratio of blue to green light intensity which provides quantitative temperature information for the surface of the model.

A Spectral Method for Color Quantitation of a Protein Drug Solution.

PubMed

Swartz, Trevor E; Yin, Jian; Patapoff, Thomas W; Horst, Travis; Skieresz, Susan M; Leggett, Gordon; Morgan, Charles J; Rahimi, Kimia; Marhoul, Joseph; Kabakoff, Bruce

2016-01-01

Color is an important quality attribute for biotherapeutics. In the biotechnology industry, a visual method is most commonly utilized for color characterization of liquid drug protein solutions. The color testing method is used for both batch release and on stability testing for quality control. Using that method, an analyst visually determines the color of the sample by choosing the closest matching European Pharmacopeia reference color solution. The requirement to judge the best match makes it a subjective method. Furthermore, the visual method does not capture data on hue or chroma that would allow for improved product characterization and the ability to detect subtle differences between samples. To overcome these challenges, we describe a quantitative method for color determination that greatly reduces the variability in measuring color and allows for a more precise understanding of color differences. Following color industry standards established by International Commission on Illumination, this method converts a protein solution's visible absorption spectra to L*a*b* color space. Color matching is achieved within the L*a*b* color space, a practice that is already widely used in other industries. The work performed here is to facilitate the adoption and transition for the traditional visual assessment method to a quantitative spectral method. We describe here the algorithm used such that the quantitative spectral method correlates with the currently used visual method. In addition, we provide the L*a*b* values for the European Pharmacopeia reference color solutions required for the quantitative method. We have determined these L*a*b* values by gravimetrically preparing and measuring multiple lots of the reference color solutions. We demonstrate that the visual assessment and the quantitative spectral method are comparable using both low- and high-concentration antibody solutions and solutions with varying turbidity. In the biotechnology industry, a visual assessment is the most commonly used method for color characterization, batch release, and stability testing of liquid protein drug solutions. Using this method, an analyst visually determines the color of the sample by choosing the closest match to a standard color series. This visual method can be subjective because it requires an analyst to make a judgment of the best match of color of the sample to the standard color series, and it does not capture data on hue and chroma that would allow for improved product characterization and the ability to detect subtle differences between samples. To overcome these challenges, we developed a quantitative spectral method for color determination that greatly reduces the variability in measuring color and allows for a more precise understanding of color differences. The details of the spectral quantitative method are described. A comparison between the visual assessment method and spectral quantitative method is presented. This study supports the transition to a quantitative spectral method from the visual assessment method for quality testing of protein solutions. © PDA, Inc. 2016.

Physical stability assessment and sensory optimization of a dairy-free emulsion using response surface methodology.

PubMed

Granato, Daniel; de Castro, I Alves; Ellendersen, L Souza Neves; Masson, M Lucia

2010-04-01

Desserts made with soy cream, which are oil-in-water emulsions, are widely consumed by lactose-intolerant individuals in Brazil. In this regard, this study aimed at using response surface methodology (RSM) to optimize the sensory attributes of a soy-based emulsion over a range of pink guava juice (GJ: 22% to 32%) and soy protein (SP: 1% to 3%). WHC and backscattering were analyzed after 72 h of storage at 7 degrees C. Furthermore, a rating test was performed to determine the degree of liking of color, taste, creaminess, appearance, and overall acceptability. The data showed that the samples were stable against gravity and storage. The models developed by RSM adequately described the creaminess, taste, and appearance of the emulsions. The response surface of the desirability function was used successfully in the optimization of the sensory properties of dairy-free emulsions, suggesting that a product with 30.35% GJ and 3% SP was the best combination of these components. The optimized sample presented suitable sensory properties, in addition to being a source of dietary fiber, iron, copper, and ascorbic acid.

A clinical trial of Empress II porcelain inlays luted to vital teeth with a dual-curing adhesive system and a self-curing resin cement.

PubMed

Fabianelli, Andrea; Goracci, Cecilia; Bertelli, Egidio; Davidson, Carel L; Ferrari, Marco

2006-12-01

The aim of the study was to clinically evaluate Empress II inlays cemented with a dual-curing bonding agent and a self-curing luting system. Forty patients were selected to receive one Empress II inlay. Empress II is a heat-pressed glass ceramic containing lithium disilicate and lithium orthophosphate crystals, purported to provide higher stress resistance and improved strength. The restorations were placed between March and May 2000. Recalls were performed after 6, 12, 24, and 36 months. At the 3-year recall, 7 patients were lost to follow-up. Inlays were evaluated for postoperative sensitivity, marginal integrity, marginal leakage, color stability, surface staining, retention, and surface crazing (microcracks). At the 3-year recall, all the restorations were in place and only one showed postoperative sensitivity (at the first recall, 1 week after placement). Only 3 inlays showed slight marginal staining, and 4 inlays showed gaps, with little surface staining or microcracks. No inlay debonded or fractured during theobservation period. All the evaluated inlays were in place and acceptable.

The Effect of pH and Color Stability of Anthocyanin on Food Colorant

NASA Astrophysics Data System (ADS)

Wahyuningsih, S.; Wulandari, L.; Wartono, M. W.; Munawaroh, H.; Ramelan, A. H.

2017-04-01

Anthocyanins are naturally occurring pigments of red and purple. Red anthocyanin pigments provide a strong and sharp and widely applied in various industries such as food coloring or drink. Anthocyanins isolated by maceration, extraction and thin layer chromatography (TLC). The extract has been obtained from the initial stages of maceration then separated into several fractions by chromatography to isolate fractions colored dark red. Identification of chemical compounds with TLC (Thin Layer Chromatography) is able to distinguish the fraction of anthocyanin produced. FTIR (Fourier Transform Infrared Spectroscopy) used to identification of the functional group of a compound. The UV-Vis absorption spectra have to produce maximum absorbance values that describe the intensity of anthocyanin spectra in different colors for different pH. Anthocyanins are more stable at low pH (acidic conditions) which gives a red pigment. Meanwhile, the higher the pH value of anthocyanin will provide color fading of the color blue. So as a food colorant, anthocyanin with a low pH or height pH has a significant effect on the food colorant.

The spread of attention across features of a surface

PubMed Central

Ernst, Zachary Raymond; Jazayeri, Mehrdad

2013-01-01

Contrasting theories of visual attention have emphasized selection by spatial location, individual features, and whole objects. We used functional magnetic resonance imaging to ask whether and how attention to one feature of an object spreads to other features of the same object. Subjects viewed two spatially superimposed surfaces of random dots that were segregated by distinct color-motion conjunctions. The color and direction of motion of each surface changed smoothly and in a cyclical fashion. Subjects were required to track one feature (e.g., color) of one of the two surfaces and detect brief moments when the attended feature diverged from its smooth trajectory. To tease apart the effect of attention to individual features on the hemodynamic response, we used a frequency-tagging scheme. In this scheme, the stimulus features (color and direction of motion) are modulated periodically at distinct frequencies so that the contribution of each feature to the hemodynamics can be inferred from the harmonic response at the corresponding frequency. We found that attention to one feature (e.g., color) of one surface increased the response modulation not only to the attended feature but also to the other feature (e.g., motion) of the same surface. This attentional modulation was evident in multiple visual areas and was present as early as V1. The spread of attention to the behaviorally irrelevant features of a surface suggests that attention may automatically select all features of a single object. Thus object-based attention may be supported by an enhancement of feature-specific sensory signals in the visual cortex. PMID:23883860

Out-coupling membrane for large-size organic light-emitting panels with high efficiency and improved uniformity

NASA Astrophysics Data System (ADS)

Ding, Lei; Wang, Lu-Wei; Zhou, Lei; Zhang, Fang-hui

2016-12-01

An out-coupling membrane embedded with a scattering film of SiO2 spheres and polyethylene terephthalate (PET) plastic was successfully developed for 150 × 150 mm2 green OLEDs. Comparing with a reference OLED panel, an approximately 1-fold enhancement in the forward emission was obtained with an out-coupling membrane adhered to the surface of the external glass substrate of the panel. Moreover, it was verified that the emission color at different viewing angles can be stabilized without apparent spectral distortion. Particularly, the uniformity of the large-area OLEDs was greatly improved. Theoretical calculation clarified that the improved performance of the lighting panels is primarily attributed to the effect of particle scattering.

What determines the relationship between color naming, unique hues, and sensory singularities: Illuminations, surfaces, or photoreceptors?

PubMed

Witzel, Christoph; Cinotti, François; O'Regan, J Kevin

2015-01-01

The relationship between the sensory signal of the photoreceptors on one hand and color appearance and language on the other hand is completely unclear. A recent finding established a surprisingly accurate correlation between focal colors, unique hues, and so-called singularities in the laws governing how sensory signals for different surfaces change across illuminations. This article examines how this correlation with singularities depends on reflectances, illuminants, and cone sensitivities. Results show that this correlation holds for a large range of illuminants and for a large range of sensors, including sensors that are fundamentally different from human photoreceptors. In contrast, the spectral characteristics of the reflectance spectra turned out to be the key factor that determines the correlation between focal colors, unique hues, and sensory singularities. These findings suggest that the origins of color appearance and color language may be found in particular characteristics of the reflectance spectra that correspond to focal colors and unique hues.

Color Constancy in Two-Dimensional and Three-Dimensional Scenes: Effects of Viewing Methods and Surface Texture.

PubMed

Morimoto, Takuma; Mizokami, Yoko; Yaguchi, Hirohisa; Buck, Steven L

2017-01-01

There has been debate about how and why color constancy may be better in three-dimensional (3-D) scenes than in two-dimensional (2-D) scenes. Although some studies have shown better color constancy for 3-D conditions, the role of specific cues remains unclear. In this study, we compared color constancy for a 3-D miniature room (a real scene consisting of actual objects) and 2-D still images of that room presented on a monitor using three viewing methods: binocular viewing, monocular viewing, and head movement. We found that color constancy was better for the 3-D room; however, color constancy for the 2-D image improved when the viewing method caused the scene to be perceived more like a 3-D scene. Separate measurements of the perceptual 3-D effect of each viewing method also supported these results. An additional experiment comparing a miniature room and its image with and without texture suggested that surface texture of scene objects contributes to color constancy.

Color center annealing and ageing in electron and ion-irradiated yttria-stabilized zirconia

NASA Astrophysics Data System (ADS)

Costantini, Jean-Marc; Beuneu, François

2005-04-01

We have used X-band electron paramagnetic resonance (EPR) measurements at room-temperature (RT) to study the thermal annealing and RT ageing of color centers induced in yttria-stabilized zirconia (YSZ), i.e. ZrO2:Y with 9.5 mol% Y2O3, by swift electron and ion-irradiations. YSZ single crystals with the <1 0 0> orientation were irradiated with 2.5 MeV electrons, and implanted with 100 MeV 13C ions. Electron and ion beams produce the same two color centers, namely an F+-type center (singly ionized oxygen vacancy) and the so-called T-center (Zr3+ in a trigonal oxygen local environment) which is also produced by X-ray irradiations. Isochronal annealing was performed in air up to 973 K. For both electron and ion irradiations, the defect densities are plotted versus temperature or time at various fluences. The influence of a thermal treatment at 1373 K of the YSZ single crystals under vacuum prior to the irradiations was also investigated. In these reduced samples, color centers are found to be more stable than in as-received samples. Two kinds of recovery processes are observed depending on fluence and heat treatment.

Color Stability of Silicone or Acrylic Denture Liners: An in Vitro Investigation

PubMed Central

Ergun, Gulfem; Nagas, Isil Cekic

2007-01-01

Objectives The aim of this study was to compare the color stability of three acrylic based hard liners (Ufi gel hard, Dura-Liner II, Tokuso Rebase) and two silicone based soft liners (Ufi gel permanent, Molloplast B) by using the colorimeter. Methods Sixty disc-shaped samples, with uniform size of 10 mm diameter and 2 mm in thickness were fabricated for each material. Thirty samples were made as control group in distilled water and the remaining thirty samples were weathered in accelerated aging chamber. Color measurements were made before and after distilled water and aging. Data were statistically analyzed using nonparametric Kruskal-Wallis and Mann-Whitney U tests. Results Data showed that there are significant differences among materials in both after distilled water and aging treatments (P<.001). These results indicated that the most discolored liner material was Dura Liner II after aging (ΔE*=16.30) and the least discolored material was Ufi gel permanent after distilled water (ΔE*=0.41). Conclusions Based on the results of this study, silicone based liner materials are considered to be more color stable than acrylic based liner materials. PMID:19212558

Cd-free Cu-Zn-In-S/ZnS quantum dots@SiO2 multiple cores nanostructure: preparation and application for white LEDs

NASA Astrophysics Data System (ADS)

Jiang, Tongtong; Shen, Mohan; Dai, Peng; Wu, Mingzai; Yu, Xinxin; Li, Guang; Xu, Xiaoliang; Zeng, Haibo

2017-10-01

The work reports the fabrication of Cu doped Zn-In-S (CZIS) alloy quantum dots (QDs) using dodecanethiol and oleic acid as stabilizing ligands. With the increase of doped Cu element, the photoluminescence (PL) peak is monotonically red shifted. After coating ZnS shell, the PL quantum yield of CZIS QDs can reach 78%. Using reverse micelle microemulsion method, CZIS/ZnS QDs@SiO2 multi-core nanospheres were synthesized to improve the colloidal stability and avoid the aggregation of QDs. The obtained multi-core nanospheres were dispersed in curing adhesive, and applied as a color conversion layer in down converted light-emitting diodes. After encapsulation in curing adhesive, the newly designed LEDs show artifically regulated color coordinates with varying the weight ratio of green QDs and red QDs, and the concentrations of these two types of QDs. Moreover, natural white and warm white LEDs with correlated color temperature of 5287, 6732, 2731, and 3309 K can be achieved, which indicates that CZIS/ZnS QDs@SiO2 nanostructures are promising color conversion layer material for solid-state lighting application.

Physical properties of heat-treated rattan waste binderless particleboard

NASA Astrophysics Data System (ADS)

Tajuddin, Maisarah; Ahmad, Zuraida; Halim, Zahurin; Maleque, Md Abd; Ismail, Hanafi; Sarifuddin, Norshahida

2017-07-01

The objective of this study is to investigate the effects of heat treatment on the properties of binderless particleboard (BPB) fabricated via hot-pressing process with pressing temperature, pressing time and pressing pressure of 180°C, 5 minutes and 1 MPa, respectively. The fabricated BPB with density in the range of 0.8-0.95g cm-3 was heated in a temperature-controlled laboratory chamber at 80°C, 120°C and 160°C for period of 2 and 8 hours before underwent physical observation, mass loss measurement and thickness swelling test. The samples had remarkable color changes, mainly with samples of treatment temperature of 160˚C, where the color differences were 9.5 and 20.3. This changed the fabricated BPB samples from yellowish brown to dark brown color when treatment conditions increased. Darker color indicates greater mass loss due to severity of chemical component in the powder. Dimensional stability of fabricated BPB was improved with higher treatment temperature as more cellulose cross-linked and hemicellulose degraded that removed the hygroscopicity behavior of powder. These results revealed that heat treatment helped in improving the BPB physical properties, particularly in dimensional stability of boards.

[Mechanical property of tooth-like yttria-stabilized tetragonal zirconia polycrystal by adding rare earth oxide].

PubMed

Gao, Yan; Zhang, Fuqiang; Gao, Jianhua

2012-02-01

To evaluate the influence of mechanical property of tooth-like yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) by adding rare earth oxide as colorants. Six kinds of tooth-like Y-TZP were made by introducing internal coloration technology. The colorants included rare earth oxide (Pr6O11, CeO2, Er2O3) and transition element oxide (MnO2). Mechanical properties (flexural strength, vickers hardness and fracture toughness) were tested. Microstructure was examined by scanning electron microscope(SEM), and the fracture model was analyzed. The range of flexural strength of the six kinds of tooth-like Y-TZP were (792 +/- 20)-(960 +/- 17) MPa, the fracture toughness were (4.72 +/- 0.31)-(5.64 +/- 0.38) MPam(1/2), and the vickers hardness were (1332 +/- 19)-(1380 +/- 17) MPa. SEM observation on the cross section of the six kinds of sintered composites showed a relatively dense polycrystal structure, and the fracture models was mixed type. Tooth-like Y-TZP is acquired with better mechanical properties (fracture toughness and vickers hardness) by adding rare earth oxide as colorants. It is available for clinical application.

False Color Surface

NASA Image and Video Library

2014-12-26

The THEMIS VIS camera contains 5 filters. The data from different filters can be combined in multiple ways to create a false color image. This false color image from NASA 2001 Mars Odyssey spacecraft shows part of the region near Nili Fossae.

Color Map of Ceres Elliptical Projection

NASA Image and Video Library

2016-03-22

This global map elliptical map from NASA Dawn spacecraft shows the surface of Ceres in enhanced color, encompassing infrared wavelengths beyond human visual range. Some areas near the poles are black where Dawn color imaging coverage is incomplete.

Infrared actuation-induced simultaneous reconfiguration of surface color and morphology for soft robotics.

PubMed

Banisadr, Seyedali; Chen, Jian

2017-12-13

Cephalopods, such as cuttlefish, demonstrate remarkable adaptability to the coloration and texture of their surroundings by modulating their skin color and surface morphology simultaneously, for the purpose of adaptive camouflage and signal communication. Inspired by this unique feature of cuttlefish skins, we present a general approach to remote-controlled, smart films that undergo simultaneous changes of surface color and morphology upon infrared (IR) actuation. The smart film has a reconfigurable laminated structure that comprises an IR-responsive nanocomposite actuator layer and a mechanochromic elastomeric photonic crystal layer. Upon global or localized IR irradiation, the actuator layer exhibits fast, large, and reversible strain in the irradiated region, which causes a synergistically coupled change in the shape of the laminated film and color of the mechanochromic elastomeric photonic crystal layer in the same region. Bending and twisting deformations can be created under IR irradiation, through modulating the strain direction in the actuator layer of the laminated film. Furthermore, the laminated film has been used in a remote-controlled inchworm walker that can directly couple a color-changing skin with the robotic movements. Such remote-controlled, smart films may open up new application possibilities in soft robotics and wearable devices.

Color Stability of CAD/CAM Fabricated Inlays after Accelerated Artificial Aging.

PubMed

Karaokutan, Isil; Yilmaz Savas, Tuba; Aykent, Filiz; Ozdere, Eda

2016-08-01

To investigate the influence of accelerated artificial aging on the color stability of three different inlay restorations produced with a CAD/CAM system. Thirty non-carious human mandibular molar teeth were used. The teeth were embedded in autopolymerizing acrylic resin blocks. Standard Class I inlay cavities were prepared, and the teeth were randomly divided into three groups (n = 10) to fabricate inlay restorations: (1) a feldspathic-ceramic group, (2) a resin nano-ceramic group, and (3) a leucite glass-ceramic group. Optical impressions were made with CEREC software, and the restorations were designed and then milled. The inlays were adhesively cemented with a dual-polymerizing resin cement and left in distilled water at room temperature for 1 week. Color measurements were performed with a spectrophotometer before and after accelerated aging in a weathering machine with a total energy of 150 kJ/m(2) . Changes in color (∆E, ∆L, ∆a, ∆b, ∆C) were determined using the CIE L*a*b* system. The results were assessed using a one-way ANOVA and Tukey's HSD test (p = 0.05). The color changes of the materials ranged from 2.1 to 9.29. The highest color change was seen in the resin nano-ceramic material. This change was not clinically acceptable (∆E > 5.5). No significant differences were found in the ∆L and ∆a values of the test groups. Color changes were observed in each evaluated material after accelerated aging. All CAD/CAM inlays became darker in appearance, more saturated, a little reddish, and more yellow. © 2015 by the American College of Prosthodontists.

Fresh meat packaging: consumer acceptance of modified atmosphere packaging including carbon monoxide.

PubMed

Grebitus, Carola; Jensen, Helen H; Roosen, Jutta; Sebranek, Joseph G

2013-01-01

Consumers' perceptions and evaluations of meat quality attributes such as color and shelf life influence purchasing decisions, and these product attributes can be affected by the type of fresh meat packaging system. Modified atmosphere packaging (MAP) extends the shelf life of fresh meat and, with the inclusion of carbon monoxide (CO-MAP), achieves significant color stabilization. The objective of this study was to assess whether consumers would accept specific packaging technologies and what value consumers place on ground beef packaged under various atmospheres when their choices involved the attributes of color and shelf life. The study used nonhypothetical consumer choice experiments to determine the premiums that consumers are willing to pay for extended shelf life resulting from MAP and for the "cherry red" color in meat resulting from CO-MAP. The experimental design allowed determination of whether consumers would discount foods with MAP or CO-MAP when (i) they are given more detailed information about the technologies and (ii) they have different levels of individual knowledge and media exposure. The empirical analysis was conducted using multinomial logit models. Results indicate that consumers prefer an extension of shelf life as long as the applied technology is known and understood. Consumers had clear preferences for brighter (aerobic and CO) red color and were willing to pay $0.16/lb ($0.35/kg) for each level of change to the preferred color. More information on MAP for extending the shelf life and on CO-MAP for stabilizing color decreased consumers' willingness to pay. An increase in personal knowledge and media exposure influenced acceptance of CO-MAP negatively. The results provide quantitative measures of how packaging affects consumers' acceptance and willingness to pay for products. Such information can benefit food producers and retailers who make decisions about investing in new packaging methods.

Influence of staining solutions and whitening procedures on discoloration of hybrid composite resins.

PubMed

Garoushi, Sufyan; Lassila, Lippo; Hatem, Marwa; Shembesh, Muneim; Baady, Lugane; Salim, Ziad; Vallittu, Pekka

2013-01-01

The aim was to evaluate the color stability and water uptake of two hybrid composite resins polymerized in two different conditions after exposure to commonly consumed beverages. In addition, the effect of repolishing and bleaching on the stained composite was evaluated. Eighty specimens (12 mm × 12 mm × 3 mm) were made from two hybrid composite resins of shade A2. Forty specimens of each composite were divided into two groups (n = 20 per each) according to the curing method used (hand light cure HLC or oven light cure OLC). Then each group (HLC or OLC) was sub-divided randomly into four sub-groups (n = 5), which were immersed for 60 days in different beverages (distal water, coffee, tea and pepsi) and incubated at 37°C. Water uptake was measured during this time and followed by measurement of color difference (ΔE) by using a spectrophotometer. After complete staining, repolishing (grit 4000 FEPA at 300 rpm under water) and bleaching (40% hydrogen peroxide bleaching gel) were conducted. The repolished and bleached specimens were submitted to new color measurements. Color value of the specimens immersed in tea displayed the highest statistically significant (p < 0.05) mean color difference (ΔE) compared to other beverages, whereas the ΔE value of pepsi was significantly lower than the others. After staining of the composite resins, both the bleaching and repolishing were able to reduce the ΔE value. All beverages used affected the color stability of tested composite resins. The effect of beverages on color change of composites depends on type of beverage and water uptake value of resins used. A superior whitening effect was obtained with repolishing technique compared to bleaching.

7 CFR 51.1403 - Kernel color classification.

Code of Federal Regulations, 2011 CFR

2011-01-01

... classifications provided in this section. When the color of kernels in a lot generally conforms to the “light” or “light amber” classification, that color classification may be used to describe the lot in connection with the grade. (1) “Light” means that the outer surface of the kernel is mostly golden color or...

7 CFR 51.1403 - Kernel color classification.

Code of Federal Regulations, 2012 CFR

2012-01-01

... classifications provided in this section. When the color of kernels in a lot generally conforms to the “light” or “light amber” classification, that color classification may be used to describe the lot in connection with the grade. (1) “Light” means that the outer surface of the kernel is mostly golden color or...

Food Fortification Stability Study

NASA Technical Reports Server (NTRS)

Sirmons, T. A.; Cooper, M. R.; Douglas, G. L.

2016-01-01

This study aims to assess the stability of vitamin content, sensory acceptability and color variation in fortified spaceflight foods over a period of 2 years. Findings will identify optimal formulation, processing, and storage conditions to maintain stability and acceptability of commercially available fortification nutrients. Changes in food quality are being monitored to indicate whether fortification affects quality over time (compared to the unfortified control), thus indicating their potential for use on long-duration missions.

Food Fortification Stability Study

NASA Technical Reports Server (NTRS)

Sirmons, T. A.; Cooper, M. R.; Douglas, G. L.

2017-01-01

This study aimed to assess the stability of vitamin content, sensory acceptability and color variation in fortified spaceflight foods over a period of two years. Findings will help to identify optimal formulation, processing, and storage conditions to maintain stability and acceptability of commercially available fortification nutrients. Changes in food quality were monitored to indicate whether fortification affects quality over time (compared to the unfortified control), thus indicating their potential for use on long-duration missions.

Color pattern evolution in Vanessa butterflies (Nymphalidae: Nymphalini): non-eyespot characters.

PubMed

Abbasi, Roohollah; Marcus, Jeffrey M

2015-01-01

A phylogenetic approach was used to study color pattern evolution in Vanessa butterflies. Twenty-four color pattern elements from the Nymphalid ground plan were identified on the dorsal and ventral surfaces of the fore- and hind wings. Eyespot characters were excluded and will be examined elsewhere. The evolution of each character was traced over a Bayesian phylogeny of Vanessa reconstructed from 7750 DNA base pairs from 10 genes. Generally, the correspondence between character states on the same surface of the two wings is stronger on the ventral side compared to the dorsal side. The evolution of character states on both sides of a wing correspond with each other in most extant species, but the correspondence between dorsal and ventral character states is much stronger in the forewing than in the hindwing. The dorsal hindwing of many species of Vanessa is covered with an extended Basal Symmetry System and the Discalis I pattern element is highly variable between species, making this wing surface dissimilar to the other wing surfaces. The Basal Symmetry System and Discalis I may contribute to behavioral thermoregulation in Vanessa. Overall, interspecific directional character state evolution of non-eyespot color patterns is relatively rare in Vanessa, with a majority of color pattern elements showing non-variable, non-directional, or ambiguous character state evolution. The ease with which the development of color patterns can be modified, including character state reversals, has likely made important contributions to the production of color pattern diversity in Vanessa and other butterfly groups. © 2014 Wiley Periodicals, Inc.