Elastic atomic displacements and color center creation in LiF crystals irradiated with 3-, 9- and 12-MeV Au ions

International Nuclear Information System (INIS)

Sorokin, M.V.; Papaleo, R.M.; Schwartz, K.

2009-01-01

Creation of color centers in LiF under irradiation with 3-12-MeV Au ions was studied. Comparison of experimental data of color center creation with computer simulation of the energy deposition and elastic atomic displacements reveals the role of elastic collisions in defect creation by these ions, which have comparable magnitudes of electronic and elastic stopping. The experimentally measured efficiency of color center creation and that predicted by the simulation of elastic displacements have a similar dependence on the projectile energy. Thus, the color center creation is mainly associated with the elastic collisions, despite the relatively large values of the electronic stopping power for these ions. (orig.)

Near-surface layer radiation color centers in lithium fluoride nanocrystals: Luminescence and composition

Energy Technology Data Exchange (ETDEWEB)

Voitovich, A.P., E-mail: voitovich@imaph.bas-net.by; Kalinov, V.S.; Stupak, A.P.; Novikov, A.N.; Runets, L.P.

2015-01-15

Lithium fluoride nanocrystals are irradiated by gamma quanta at 77 K. The radiation color centers formed in a near-surface layer of nanocrystals are studied. Absorption, luminescence and luminescence excitation spectra of the surface defects have been measured. It has been found that the luminescence excitation spectra for aggregated surface centers consist of two or three bands with not very much different intensities. Reactions of the surface centers separately with electrons and with anion vacancies have been investigated. Numbers of anion vacancies and electrons entering into the centers composition have been established and it has been found that F{sub S1}, F{sub S1}{sup −}, F{sub S2}, F{sub S2}{sup −}, F{sub S3}{sup +} and F{sub S3} types of the surface centers are formed. The degree of luminescence polarization has been defined and it has been determined that the polarization degree for F{sub S2}{sup +} centers changes sign under transition from one excitation band to another. It has been shown that during irradiation at 77 K radiation-induced defects are formed more efficiently on the surface than in the bulk. - Highlights: • Radiative color centers were fabricated in lithium fluoride nanocrystals. • The unique absorption and luminescence characteristics are inherent in the centers. • The reactions of these centers with electrons and anion vacancies were studied. • The degree of luminescence polarization was defined. • Numbers of anion vacancies and electrons forming the centers were established.

Radiation Induced Color Centers in a La Doped PWO Crystal

CERN Document Server

Deng, Qun

1998-01-01

This report presents result of a study on radiation induced color center densities in a La doped lead tungstate ( PWO) crystal. The creation and annihilation constants of radiation induced color centers were determined by using transmittance data measured for a PWO sample before and during Co-60 gamma ray irradiation at a dose rate of 15 rad/hr. Following a model of color center kinetics, these constants were used to calculate color center densities under irradiations at 100 rad/hr. The result was found to be in a good agreement with experimental data, indicating that this model of color center kinetics can be used to predict behavior of PWO crystals under irradiation.

Color formation on irradiated polystyrene by electrons beam; Formacao de cor no poliestireno irradiado com feixes de eletrons

Energy Technology Data Exchange (ETDEWEB)

Nardi, Daniela T.; Guedes, Selma M.L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: smguedes@ipen.br

2005-07-01

The color formation on national and commercial polystyrene (PS) irradiated by electrons beam was investigated in function of dose (0-150 kGy), post-irradiation time (0-31 days) and heating by colorimetry (CIELab), electron spectroscopy resonance (RPE) and photoacoustic infrared spectroscopy (FTIR-PAS). Visually or by colorimetric parameters the radiation became the PS yellow and dark which intensified by increase the dose and disappeared after the post-irradiation time. Variations of green/red colors were insignificant. After post irradiation time of 30 days (150 kGy) or the heating (150 kGy) both yellow color and darkening decreased significantly showing the unstable color centers formation during the irradiation. The RPE spectra indicated that the radicals can be responsible by the formation of these color centers but there can not be responsible s by stable color centers. The FTIR-PAS spectra did not show the presence of different functional groups after irradiation. The PS studied can be radiosterilized (25 kGy) without significant colorimetric changes because it is radioresistant. (author)

Color centers of a borosilicate glass induced by 10 MeV proton, 1.85 MeV electron and 60Co-γ ray

Science.gov (United States)

Du, Jishi; Wu, Jiehua; Zhao, Lili; Song, Lixin

2013-05-01

Optical absorption spectra, electron paramagnetic resonance (EPR) spectra, Raman spectra of a borosilicate glass after irradiation by 10 MeV proton, 1.85 MeV electron and 60Co-γ ray were studied. The process of irradiation inducing color centers in the glass was discussed. The band gap of the glass before and after 60Co-γ ray irradiation was studied using Mott and Davis's theory, and it was found that calculated change of the band gap introduced a paradox, because Mott and Davis's theory on the band gap cannot be adopted in the study on the irradiated glass.

Electron Spin Resonance Shift and Linewidth Broadening of Nitrogen-Vacancy Centers in Diamond as a Function of Electron Irradiation Dose

OpenAIRE

Kim, Edwin; Acosta, Victor M.; Bauch, Erik; Budker, Dmitry; Hemmer, Philip R.

2009-01-01

A high-nitrogen-concentration diamond sample was subject to 200-keV electron irradiation using a transmission electron microscope. The optical and spin-resonance properties of the nitrogen-vacancy (NV) color centers were investigated as a function of the irradiation dose up to 6.4\\times1021 e-/cm2. The microwave transition frequency of the NV- center was found to shift by up to 0.6% (17.1 MHz) and the linewidth broadened with increasing electron-irradiation dose. Unexpectedly, the measured ma...

Optical properties of color centers in calcium-stabilized gadolinium gallium garnets

International Nuclear Information System (INIS)

Pogatshnik, G.J.; Cain, L.S.; Chen, Y.; Evans, B.D.

1991-01-01

The addition of small amounts of calcium during the crystal growth of large-diameter, gadolinium gallium garnet (GGG) crystals creates color centers that absorb in the near-uv region of the spectrum. Ultraviolet and γ-ray irradiation of the crystals produced changes in the intensities of the uv color-center bands along with a broad absorption throughout the visible spectrum. The color center that gives rise to an absorption band at 350 nm serves as a photoionizable donor center so that uv excitation results in a visible coloration of the crystals. The effects of oxidation and reduction treatments on the strength of the color-center bands and on the radiation response of the material were examined. Photoluminescence bands were observed in both reduced GGG crystals as well as crystals that were irradiated with neutrons. Visible coloration is likely to occur during flashlamp pumping of laser rods that utilize large-diameter GGG crystals as the laser host. The changes in the optical properties of the material under uv excitation indicate that the addition of small amounts of calcium to assist in the growth of large-diameter crystals is likely to result in the degradation of laser performance

Probing Xe electronic structure by two-color HHG

International Nuclear Information System (INIS)

Faccialà, D; Ciriolo, A G; De Silvestri, S; Devetta, M; Negro, M; Stagira, S; Vozzi, C; Pabst, S; Bruner, B D; Dudovich, N; Soifer, H

2015-01-01

The aim of this study is probing the multi-electron behavior in xenon by two-color driven high harmonic generation. By changing the relative polarization of the two colors we were able to study different aspects of the multi-electron response. (paper)

Color formation study of irradiated polymers by electron beam; Estudo da formacao de cor em polimeros irradiaddos com feixe de eletrons

Energy Technology Data Exchange (ETDEWEB)

Nardi, Daniela Teves

2004-07-01

Color formation on national and commercial polymers (polymethyl methacrylate, polystyrene and polycarbonate) irradiated by electrons beam was investigated by colorimetry (CIELab), electron spectroscopy resonance (ESR), photoacoustic infrared spectroscopy (FTIR-PAS) and differential exploratory calorimetry (DSC). The heat effect on colorimetric properties was investigated after heating (110 deg C for 1 hour) of irradiated polymers at 150 kGy. The rule of oxygen in colorimetric properties of irradiated polycarbonate was investigated in the air presence and absence (p = 10{sup -3} mmHg). The visual aspect did not agree with colorimetric parameters only for polycarbonate. Yellow color and darkness were induced by radiation for all studied polymers varying only the intensity and behavior in function of post-irradiation time and heating. Polymethyl methacrylate and polystyrene ESR spectra showed that radicals could be responsible by yellow color centers. Wherever, in polycarbonate, color centers were not due radical species. The nature of color centers for any studied polymer was not study by FTIR-PAS because there were no changes in FTIR-PAS spectra neither in function of dose nor heating. Polycarbonate was the most radiosensible and polystyrene was the most radioresistant of all studied polymers in concern of colorimetric properties. (author)

Nitrogen-Vacancy color center in diamond-emerging nanoscale applications in bioimaging and biosensing.

Science.gov (United States)

Balasubramanian, Gopalakrishnan; Lazariev, Andrii; Arumugam, Sri Ranjini; Duan, De-Wen

2014-06-01

Nitrogen-Vacancy (NV) color center in diamond is a flourishing research area that, in recent years, has displayed remarkable progress. The system offers great potential for realizing futuristic applications in nanoscience, benefiting a range of fields from bioimaging to quantum-sensing. The ability to image single NV color centers in a nanodiamond and manipulate NV electron spin optically under ambient condition is the main driving force behind developments in nanoscale sensing and novel imaging techniques. In this article we discuss current status on the applications of fluorescent nanodiamonds (FND) for optical super resolution nanoscopy, magneto-optical (spin-assisted) sub-wavelength localization and imaging. We present emerging applications such as single molecule spin imaging, nanoscale imaging of biomagnetic fields, sensing molecular fluctuations and temperatures in live cellular environments. We summarize other current advances and future prospects of NV diamond for imaging and sensing pertaining to bio-medical applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

Radiation-induced color centers in La-doped PbWO sub 4 crystals

CERN Document Server

Deng, Q; Zhu, R Y

1999-01-01

This report presents the result of a study on radiation-induced color center densities in La-doped lead tungstate (PbWO sub 4) crystals. The creation and annihilation constants of radiation-induced color centers were determined by using transmittance data measured for a PbWO sub 4 sample before and during sup 6 sup 0 Co gamma-ray irradiation at a dose rate of 15 rad/h. Following a model of color center kinetics, these constants were used to calculate color center densities under irradiations at 100 rad/h. The result was found to be in good agreement with experimental data, indicating that the behaviour of PbWO sub 4 crystals under irradiation can be predicted according to this model.

Color centers in KCN: a structural analysis of crystalline domains

International Nuclear Information System (INIS)

Carmo, L.C.S. do.

1976-03-01

Pure singlecrystals of KCN exposed to X-rays showed several color centers detected by EPR. The F center was identified through the correlation of its optical absorption band which satisfies the Ivey law for the KCN lattice parameter and the EPR spectrum typical of a center in an anionic site. Two other color centers were identified: N - 2 and HCN - . Two centers assigned to hydrogen atoms have their models proposed: U 2 and U 3 centers. Two other centers remain unidentified: an anionic and an extrinsic centers. The orthorhombic character of the N - 2 center EPR parameters allowed an structural analysis of the crystal line domains in the orthorhombic phase. The optical absorption spectrum of the HCN - center in KCl matrix was investigated and showed a set of resolved bands with a constant energy splitting; this splitting was associated to a vibrational mode of the excited state of this molecular ion. (author) [pt

Radiation-Induced Color Centers in LiF for Dosimetry at High Absorbed Dose Rates

DEFF Research Database (Denmark)

McLaughlin, W. L.; Miller, Arne; Ellis, S. C.

1980-01-01

Color centers formed by irradiation of optically clear crystals of pure LiF may be analyzed spectrophotometrically for dosimetry in the absorbed dose range from 102 to 107 Gy. Routine monitoring of intense electron beams is an important application. Both 6LiF and 7LiF forms are commercially...... available, and when used with filters as albedo dosimeters in pairs, they provide discrimination of neutron and gamma-ray doses....

Color change of tourmaline by heat treatment and electron beam irradiation: UV-Visible, EPR, and Mid-IR spectroscopic analyses

Science.gov (United States)

Maneewong, Apichate; Seong, Baek Seok; Shin, Eun Joo; Kim, Jeong Seog; Kajornrith, Varavuth

2016-01-01

The color of pink tourmaline gemstone changed to colorless when heating at temperature of 600 °C in air. This colorless tourmaline recovered its pink color when irradiated with an electron beam (e-beam) of 800 kGy. The origin of the color change was investigated in three types of tourmaline gemstones, two pink are from Afghanistan and one green are from Nigeria, by using Ultraviolet-visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), Electron paramagnetic resonance (EPR), and Energy Dispersive X-ray Fluorescence (EDXRF). The UV-Vis absorption spectrum of the pink tourmaline with higher Mn concentration (T2, 0.24 wt%) showed characteristic absorption peaks originating from the Mn3+ color center: two absorption bands centered at wavelength of 396 and 520 nm, respectively. Both absorption bands disappeared when heated in air at 600 °C and then reappeared when irradiated with an e-beam at 800 kGy. EPR T2 spectra showed that the color change was related to the valence change of Mn3+ to Mn2+ and vice versa. The pink tourmaline of lower MnO content (T1, 0.08 wt%) also became colorless when heated, but the color was not recovered when the gemstone underwent e-beam irradiation. Instead, a yellow color was obtained. UV-Vis and FTIR spectra indicated that this yellow color originated from a decomposition of the hydroxyl group (-OH) into O- and Ho by the e-beam irradiation. Green tourmaline did not show any color change with either heat treatment or e-beam irradiation.

Formation of H a - hydrogen centers upon additive coloration of alkaline-earth fluoride crystals

Science.gov (United States)

Radzhabov, E. A.; Egranov, A. V.; Shendrik, R. Yu.

2017-06-01

The mechanism of coloration of alkaline-earth fluoride crystals CaF2, SrF2, and BaF2 in calcium vapors in an autoclave with a cold zone is studied. It was found that the pressure in the autoclave upon constant evacuation by a vacuum pump within the temperature range of 500-800°C increases due to evaporation of metal calcium. In addition to the optical-absorption bands of color centers in the additively colored undoped crystals or to the bands of divalent ions in the crystals doped with rare-earth Sm, Yb, and Tm elements, there appear intense bands in the vacuum ultraviolet region at 7.7, 7.0, and 6.025 eV in CaF2, SrF2, and BaF2, respectively. These bands belong to the Ha - hydrogen centers. The formation of hydrogen centers is also confirmed by the appearance of the EPR signal of interstitial hydrogen atoms after X-ray irradiation of the additively colored crystals. Grinding of the outer edges of the colored crystals leads to a decrease in the hydrogen absorption-band intensity with depth to complete disappearance. The rate of hydrogen penetration inside the crystal is lower than the corresponding rate of color centers (anion vacancies) by a factor of tens. The visible color density of the outer regions of the hydrogen-containing crystals is several times lower than that of the inner region due to the competition between the color centers and hydrogen centers.

Radiation induced color in topaz crystals

International Nuclear Information System (INIS)

Castagnet, A.C.; Rocca, H.C.C.; Rostilato, M.E.C.M.

1989-08-01

The presence of defects and impurities in the crystal lattice alters the eletric field distribution within the crystal, allowing the electrons to occupy energy levels in the forbbiden band. Ionizing radiation supply the required energy to permit the electrons originaly bound to lattice atoms, to occupy effectively those intermediate levels, forming color centers. Dependig upon the nature and energy of the radiation, it is possible to produce defects in regions of the crystal, generating color centers. Based on these premises, a technique to induce color in originally colorless topaz, by using the IEA-R1 nuclear reactor, was developed at Engineering and Industrial Application Department (TE). Samples were irradiated inside iron capsules coated with cadmium foils. The iron, and principaly the cadmium, absorb the thermal neutrons that could activate crystal impurities generating long-lived radioisotopes. The epithermal neutrons that overpass the iron and cadmium barriers interact with the crystal atoms, causing lattice defects which give rise to color center, by subsequent ionization processes. The procedure used at TE induces permanent blue color, in natural colorless topaz. (author) [pt

Color centers inside crystallic active media

Science.gov (United States)

Mierczyk, Zygmunt; Kaczmarek, Slawomir M.; Kopczynski, Krzysztof

1995-03-01

This paper presents research results on color centers induced by radiation of a xenon lamp in non doped crystals of yttrium aluminum garnet Y3Al5O12 (YAG), strontium- lanthanum aluminate SrLaAlO4 (SLAO), strontium-lanthanum gallate SrLaGa3O7 (SLGO), and in doped crystals: Nd:YAG, Cr, Tm, Ho:YAG (CTH:YAG), Nd:SLAO and Nd:SLGO. In all these investigated crystals under the influence of intensive exposure by xenon lamp radiation additional bands connected with centers O-2, O2 and centers F came up near the short-wave absorption edge. In the case of doped crystals the observed processes are much more complicated. In crystals CTH:YAG the greatest perturbations in relation to basic state are present at the short-wave absorption edge, as well as on areas of absorption bands of ions Cr+3 and Tm+3 conditioning the sensibilization process of ions Ho+3. These spectral structure disturbances essentially influence the efficiency of this process, as proven during generating investigations. In the case of SrLaGa3O7:Nd+3 under the influence of exposure substantial changes of absorption spectrum occurred on spectral areas 346 divided by 368 nm, 429 divided by 441 nm and 450 divided by 490 nm. Those changes have an irreversible character. They disappear not before the plate is being held at oxidizing atmosphere. Investigations of laser rods Nd:SLGO, CTH:YAG, and Nd:YAG in a free generation demonstrated that the color centers of these crystals are induced by pomp radiation from the spectral area up to 450 nm.

Color formation on irradiated polymethyl methacrylate by electrons beam; Formacao de cor no polimetil metacrilato (PMMA) irradiado com feixes de eletrons

Energy Technology Data Exchange (ETDEWEB)

Nardi, Daniela T.; Guedes, Selma M.L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: smguedes@ipen.br

2005-07-01

The color formation on national and commercial polymethyl methacrylate (PMMA) irradiated by electrons beam was investigated in function of dose (0-150 kGy), post-irradiation time (0-31 days) and heating (110 deg C/1 h) by colorimetry (CIELab), electron spectroscopy resonance (RPE) and photoacoustic infrared spectroscopy (FTIRPAS). The irradiation promoted the formation of unstable color centers responsible by changing of colorimetric and optical properties. Visually or by colorimetric parameters the radiation became the PMMAS yellow and darkening which intensified by increase the dose and disappeared after the post-irradiation time. The yellow color disappeared and darkening increased when the irradiated PMMA (150 kGy) was heated. It was impossible to see the green and red colors however the colorimetric parameters showed a little decreasing of the Da value in function of the increased dose and a little increasing in function of post-irradiation time. The FTIR-PAS spectra did not show the presence of different functional groups after irradiation however the correlation among the Db values and RPE spectra suggested that the radicals could be responsible by unstable and yellow color centers. The radiosterilized PMMA (25 kGy) showed significant colorimetric changes that decreased but continued visible yet after 31 days. (author)

The double luminescence of Color Centers

International Nuclear Information System (INIS)

Baldacchini, Giuseppe

2015-01-01

An experiment on the luminescence of Color Centers (CCs) carried out in 1987 at the ENEA Laboratories in Frascati had a negative result, but subsequent investigations showed that it was not a failure but rather a discovery of a new phenomenon. Since the coming of lasers, CCs in alkali halides have been successfully used as optically active materials, in particular FA Centers. One of these centers, well known for its medium infrared laser emission at 77 K, cooled further to 2 K emitted in the near infrared and without laser effect. Further investigations showed that the double luminescence was a fundamental property unknown until that time. This important discovery was achieved in Frascati because of the existence since 1973 of a solid and extensive expertise in the field of CCs, which continued over time and later on applied to the modern miniaturized photonic devices [it

Bragg superlattice for obtaining individual photoluminescence of diamond color centers in dense 3D ensembles

Science.gov (United States)

Kukushkin, V. A.

2017-10-01

A way to significantly increase the spatial resolution of the color center photoluminescence collection in chemically vapor-deposited (CVD) diamond at a fixed exciting beam focal volume is suggested. It is based on the creation of a narrow waveguide for the color center photoluminescence with a small number of allowed vertical indices of guided modes. The waveguide is formed between the top surface of a CVD diamond film and an underlaid mirror—a Bragg superlattice made of interchanging high- and low boron-doped layers of CVD diamond. The guided color center photoluminescence is extracted through the top surface of a CVD diamond film with the frustrated total internal reflection method. According to the results of simulation made for a case when color centers are nitrogen-vacancy (NV) centers, the suggested way allows to increase the maximal value of the NV center concentration still compatible with selective collection of their photoluminescence by several times at a fixed exciting beam focal volume. This increase is provided without the deterioration of the NV center photoluminescence collection efficiency.

Process of optical excitation and relaxation of color center in synthetic diamond and its application to optoelectronics

International Nuclear Information System (INIS)

Nishida, Yoshio

1989-01-01

Irradiation of high-pressure synthesized diamond is carried out by using a nuclear reactor or a linac. Then, the effect of annealing on the color centers is observed. A study is made to identify different color centers and to provide techniques to control their introduction. Investigations cover the relation of color center formation with annealing temperature, dependence of color center formation on radiation dose, migration of H3 center and hydrogen, and applicability of five different color centers to optoelectronics. Next, a study is made of the formation and relaxation of the nitrogen vacancy (NV) center in a metastable excited state produced by optical excitation. An optical gain is essential to provide laser. Optical amplification is measured at the vibronic emission band of the NV center. An increase in absorption is detected, indicating that the NV center will not provide laser. In the optical excitation-relaxation process, the relaxation proceeds via a metastable state. Finally, hole burning of ZPL of the NV center is observed in the temperature range from 20K to 80K, and some of its features are described. (N.K.)

Effect of air annealing on the color center in Yb:Y3Al5O12 transparent ceramics with MgO as sintering additive

Science.gov (United States)

Lu, Zhongwen; Lu, Tiecheng; Wei, Nian; Zhang, Wei; Ma, Benyuan; Qi, Jianqi; Guan, Yongbing; Chen, Xingtao; Wu, Huajun; Zhao, Yu

2015-09-01

High quality Yb:Y3Al5O12 (YAG) transparent ceramics were fabricated by vacuum sintering with MgO as sintering aids. The Yb:YAG samples were annealed at 1250-1450 °C for 20 h in air. The experimental results showed that the transparency of Yb:YAG samples declined markedly with the annealing temperatures of 1250-1450 °C. The samples became increasingly orange-yellow in color with the increase of annealing temperature. The potential reasons of discoloration were discussed for the first time. It was attributed to the complex color center [Mg2+F+] formed during the annealing, which was evidenced by optical absorption in the range of 300-500 nm wavelength and the presence of an electron spin resonance (ESR) line at g = 1.9806. The formation mechanism of the complex color center was explained in detail. The complex color center can be eliminated after post-HIP (hot isostatic pressing). And by air annealing and post-HIP, the transmittance of the samples increased from 80.3% to 83.4%.

Enhancing the brightness of electrically driven single-photon sources using color centers in silicon carbide

Science.gov (United States)

Khramtsov, Igor A.; Vyshnevyy, Andrey A.; Fedyanin, Dmitry Yu.

2018-03-01

Practical applications of quantum information technologies exploiting the quantum nature of light require efficient and bright true single-photon sources which operate under ambient conditions. Currently, point defects in the crystal lattice of diamond known as color centers have taken the lead in the race for the most promising quantum system for practical non-classical light sources. This work is focused on a different quantum optoelectronic material, namely a color center in silicon carbide, and reveals the physics behind the process of single-photon emission from color centers in SiC under electrical pumping. We show that color centers in silicon carbide can be far superior to any other quantum light emitter under electrical control at room temperature. Using a comprehensive theoretical approach and rigorous numerical simulations, we demonstrate that at room temperature, the photon emission rate from a p-i-n silicon carbide single-photon emitting diode can exceed 5 Gcounts/s, which is higher than what can be achieved with electrically driven color centers in diamond or epitaxial quantum dots. These findings lay the foundation for the development of practical photonic quantum devices which can be produced in a well-developed CMOS compatible process flow.

Color center lasers passively mode locked by quantum wells

International Nuclear Information System (INIS)

Islam, M.N.; Soccolich, C.E.; Bar-Joseph, I.; Sauer, N.; Chang, T.Y.; Miller, B.I.

1989-01-01

This paper describes how, using multiple quantum well (MQW) saturable absorbers, the authors passively mode locked a NaCl color center laser to produce 275 fs transform-limited, pedestal-free pulses with as high as 3.7 kW peak power. The pulses are tunable from λ = 1.59 to 1.7 μm by choosing MQW's with different bandgaps. They shortened the output pulses from the laser to 25 fs using the technique of soliton compression in a fiber. The steady-state operation of the laser requires the combination of a fast saturable absorber and gain saturation. In addition to the NaCl laser, they passively mode locked a Tl 0 (1):KCl color center laser and produced -- 22 ps pulses. Although the 275 fs pulses from the NaCl laser are Gaussian, when broadened, the pulses acquire an asymmetric spectrum because of carrier-induced refractive index changes

Preferred skin color enhancement for photographic color reproduction

Science.gov (United States)

Zeng, Huanzhao; Luo, Ronnier

2011-01-01

Skin tones are the most important colors among the memory color category. Reproducing skin colors pleasingly is an important factor in photographic color reproduction. Moving skin colors toward their preferred skin color center improves the color preference of skin color reproduction. Several methods to morph skin colors to a smaller preferred skin color region has been reported in the past. In this paper, a new approach is proposed to further improve the result of skin color enhancement. An ellipsoid skin color model is applied to compute skin color probabilities for skin color detection and to determine a weight for skin color adjustment. Preferred skin color centers determined through psychophysical experiments were applied for color adjustment. Preferred skin color centers for dark, medium, and light skin colors are applied to adjust skin colors differently. Skin colors are morphed toward their preferred color centers. A special processing is applied to avoid contrast loss in highlight. A 3-D interpolation method is applied to fix a potential contouring problem and to improve color processing efficiency. An psychophysical experiment validates that the method of preferred skin color enhancement effectively identifies skin colors, improves the skin color preference, and does not objectionably affect preferred skin colors in original images.

Photoluminescence of magnesium-associated color centers in LiF crystals implanted with magnesium ions

Science.gov (United States)

Nebogin, S. A.; Ivanov, N. A.; Bryukvina, L. I.; V. Shipitsin, N.; E. Rzhechitskii, A.; Papernyi, V. L.

2018-05-01

In the present paper, the effect of magnesium nanoparticles implanted in a LiF crystal on the optical properties of color centers is studied. The transmittance spectra and AFM images demonstrate effective formation of the color centers and magnesium nanoparticles in an implanted layer of ∼ 60-100 nm in thickness. Under thermal annealing, a periodical structure is formed on the surface of the crystal and in the implanted layer due to self-organization of the magnesium nanoparticles. Upon excitation by argon laser with a wavelength of 488 nm at 5 K, in a LiF crystal, implanted with magnesium ions as well as in heavily γ-irradiated LiF: Mg crystals, luminescence of the color centers at λmax = 640 nm with a zero-phonon line at 601.5 nm is observed. The interaction of magnesium nanoparticles and luminescing color centers in a layer implanted with magnesium ions has been revealed. It is shown that the luminescence intensity of the implanted layer at a wavelength of 640 nm is by more than two thousand times higher than that of a heavily γ-irradiated LiF: Mg crystal. The broadening of the zero-phonon line at 601.5 nm in the spectrum of the implanted layer indicates the interaction of the emitting quantum system with local field of the surface plasmons of magnesium nanoparticles. The focus of this work is to further optimize the processing parameters in a way to result in luminescence great enhancement of color centers by magnesium nanoparticles in LiF.

Electron Microscopy Center (EMC)

Data.gov (United States)

Federal Laboratory Consortium — The Electron Microscopy Center (EMC) at Argonne National Laboratory develops and maintains unique capabilities for electron beam characterization and applies those...

Studies on the radicidation of natural food colorants. Effects of irradiation with γ-ray and electron beam on functional properties of beet red colorant

International Nuclear Information System (INIS)

Higashimura, Yutaka; Tada, Mikiro

2002-01-01

For the practical use of radicidation, we studied on the effects of γ-ray and electron beam on functional properties of beet red colorant, natural colors with low heat stability and high possibility of microbe contamination. Neither γ-ray or electron beam had any significant influence on color contents and color tone of red beet products at less than 10 kGy of irradiation for the practical use. Influence of moisture content at level of less than 20% in powdered product was not observed. The results suggest that both γ-ray and electron beam irradiation is significantly effective in decontamination of powdered beet red products. (author)

Electron spin resonance of nitrogen-vacancy centers in optically trapped nanodiamonds

Science.gov (United States)

Horowitz, Viva R.; Alemán, Benjamín J.; Christle, David J.; Cleland, Andrew N.; Awschalom, David D.

2012-01-01

Using an optical tweezers apparatus, we demonstrate three-dimensional control of nanodiamonds in solution with simultaneous readout of ground-state electron-spin resonance (ESR) transitions in an ensemble of diamond nitrogen-vacancy color centers. Despite the motion and random orientation of nitrogen-vacancy centers suspended in the optical trap, we observe distinct peaks in the measured ESR spectra qualitatively similar to the same measurement in bulk. Accounting for the random dynamics, we model the ESR spectra observed in an externally applied magnetic field to enable dc magnetometry in solution. We estimate the dc magnetic field sensitivity based on variations in ESR line shapes to be approximately . This technique may provide a pathway for spin-based magnetic, electric, and thermal sensing in fluidic environments and biophysical systems inaccessible to existing scanning probe techniques. PMID:22869706

Influence of chromium ions on the color center formation in crystals with garnet structure

International Nuclear Information System (INIS)

Ashurov, M.Kh.; Zharikov, E.V.; Laptev, V.V.

1985-01-01

The in fluence of chromium ions on the color center formation in crystals of yttrium-aluminium garnet, gadolinium-gallium garnet, gadolinium-scandium-gallium garnet, and yttrium-scandium-gallium garnet is studied. In addition to basic activator ions these crystals were coactivated also by chromium ions with two wide bands of fundamental absorption within the range of pump tube radiation with maximas close to 450 and 650 nm. The color centers for γ-irradiated samples were observed at 300 K by measuring the adsorption spectra within the 300-800 nm range. Temperature of destruction of the charge trapping sites was determined by the method of thermoluminescence measuring in the 100-500 K temperature range. Detection of recombination center luminescence was accomplished within the 200-1600 nm wavelength range. Chromium ions are found to hinder the formation of color centers as a result of γ-irradiation at room and higher temperatures within the wavelength range over 300 nm; i.e. Cr 3+ ions increase radiation resistance of all the investigated crystals

Time-dependent broken-symmetry density functional theory simulation of the optical response of entangled paramagnetic defects: Color centers in lithium fluoride

Science.gov (United States)

Janesko, Benjamin G.

2018-02-01

Parameter-free atomistic simulations of entangled solid-state paramagnetic defects may aid in the rational design of devices for quantum information science. This work applies time-dependent density functional theory (TDDFT) embedded-cluster simulations to a prototype entangled-defect system, namely two adjacent singlet-coupled F color centers in lithium fluoride. TDDFT calculations accurately reproduce the experimental visible absorption of both isolated and coupled F centers. The most accurate results are obtained by combining spin symmetry breaking to simulate strong correlation, a large fraction of exact (Hartree-Fock-like) exchange to minimize the defect electrons' self-interaction error, and a standard semilocal approximation for dynamical correlations between the defect electrons and the surrounding ionic lattice. These results motivate application of two-reference correlated ab initio approximations to the M-center, and application of TDDFT in parameter-free simulations of more complex entangled paramagnetic defect architectures.

Si-related color centers in nanocrystalline diamond thin films

Czech Academy of Sciences Publication Activity Database

Potocký, Štěpán; Holovský, Jakub; Remeš, Zdeněk; Müller, Martin; Kočka, Jan; Kromka, Alexander

2014-01-01

Roč. 251, č. 12 (2014), s. 2603-2606 ISSN 0370-1972 R&D Projects: GA TA ČR TA01011740; GA ČR(CZ) GA14-04790S; GA MŠk LH12186 Institutional support: RVO:68378271 Keywords : chemical vapor deposition * color center * diamond * photoluminescence * plasma Subject RIV: BL - Plasma and Gas Discharge Physics Impact factor: 1.489, year: 2014

Characterization of color centers in quartz induced by gamma irradiation

International Nuclear Information System (INIS)

Guttler, Rainer A.S.

2009-01-01

The availability of gamma ray irradiators in Brazil increased the possibilities of treatments of gemstones for color enhancements. One of the minerals with a very high potential of these treatments is quartz, a very widespread mineral with much colored commercial varieties. Quartz occurs in Brazil mainly in two geological environments, called pegmatitic and hydrothermal. The detailed mechanism of color center formation of these two types of quartz will be investigated by spectroscopic and chemical analysis. Until yet, it can be shown that due to chemical differences of the nature of mineral forming fluids, the two types behave differently. All quartzes contain mainly traces of Iron, Aluminum, Lithium and some amounts of Water. The quartz of hydrothermal origin incorporated much structurally bound water, and despite some similarities with the chemical composition of pegmatitic quartz, this high water content is the reason for the formation of Silanol radicals, giving the green color to the quartz. The main difference in chemical composition of pegmatitic quartz is the presence of higher amounts of Al and Li , responsible for the brownish and yellowish colors formed by irradiation. Since each pegmatite is different, the quartz will behave differently. This explains the formation of the famous 'Green Gold' of quartz from Sao Jose da Safira , and the more yellowish, Citrine type, color of quartz from the Coluna deposit, near Itamarandiba, Minas Gerais. (author)

Characterization of color centers in quartz induced by gamma irradiation

Energy Technology Data Exchange (ETDEWEB)

Guttler, Rainer A.S., E-mail: rainersg@usp.b [Universidade de Sao Paulo (USP), SP (Brazil). Inst. de Geociencias; Enokihara, Cyro T.; Rela, Paulo R., E-mail: prela@ipen.b, E-mail: cteiti@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

2009-07-01

The availability of gamma ray irradiators in Brazil increased the possibilities of treatments of gemstones for color enhancements. One of the minerals with a very high potential of these treatments is quartz, a very widespread mineral with much colored commercial varieties. Quartz occurs in Brazil mainly in two geological environments, called pegmatitic and hydrothermal. The detailed mechanism of color center formation of these two types of quartz will be investigated by spectroscopic and chemical analysis. Until yet, it can be shown that due to chemical differences of the nature of mineral forming fluids, the two types behave differently. All quartzes contain mainly traces of Iron, Aluminum, Lithium and some amounts of Water. The quartz of hydrothermal origin incorporated much structurally bound water, and despite some similarities with the chemical composition of pegmatitic quartz, this high water content is the reason for the formation of Silanol radicals, giving the green color to the quartz. The main difference in chemical composition of pegmatitic quartz is the presence of higher amounts of Al and Li , responsible for the brownish and yellowish colors formed by irradiation. Since each pegmatite is different, the quartz will behave differently. This explains the formation of the famous 'Green Gold' of quartz from Sao Jose da Safira , and the more yellowish, Citrine type, color of quartz from the Coluna deposit, near Itamarandiba, Minas Gerais. (author)

Properties of the generation of radiation in the near infrared part of the spectrum with a sapphire crystal laser having radiation-induced color centers

International Nuclear Information System (INIS)

Voitovich, A.P.; Grinkevich, V.E.; Kononov, V.A.; Kromskii, G.I.

1986-01-01

This paper investigates the spectral stability of the color centers in sapphire and the energy of lasers in which the active elements were colored with various techniques. Color centers were produced by neutron irradiation. The absorption spectra of the color centers are shown. The transformation of the spectra shows that the mutual conversions of color centers takes place during the thermal annealing of the sapphire; most of the color centers formed have luminescence. Generation or radiation with a tunable frequency was obtained in the case of transverse or quasi-longitudinal excitation by a ruby laser. The results show that ways for increasing the stability of the energy generated by a sapphire laser with color centers can be found

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

Science.gov (United States)

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.

Zero-phonon lines and electron–phonon interaction characteristics of near-surface layer radiation color centers in lithium fluoride

Energy Technology Data Exchange (ETDEWEB)

Voitovich, A.P., E-mail: voitovich@ifanbel.bas-net.by [Institute of Physics, National Academy of Sciences of Belarus, 68 Nezavisimosti Avenue, 220072 Minsk (Belarus); Kalinov, V.S. [Institute of Physics, National Academy of Sciences of Belarus, 68 Nezavisimosti Avenue, 220072 Minsk (Belarus); Mudryi, A.V. [Scientific-Practical Materials Research Center, National Academy of Sciences of Belarus, 19 Brovka Street, 220072 Minsk (Belarus); Pavlovskii, V.N.; Runets, L.P.; Svitsiankou, I.E. [Institute of Physics, National Academy of Sciences of Belarus, 68 Nezavisimosti Avenue, 220072 Minsk (Belarus)

2016-04-15

Zero-phonon lines have been registered in photoluminescence spectra of near-surface layer radiation color centers in lithium fluoride nanocrystals. They have been assigned to transitions of the definite types centers. The frequencies of phonons participating in the transitions of the different type centers located both in the near-surface layer and in the crystal bulk have been measured and compared. The Huang-Rhys parameters for the transitions of these centers have been determined. It has been found that the Huang-Rhys parameters for the studied transitions in the near-surface layer centers of the certain composition are less than for those in the crystal bulk centers of the same composition. This feature is connected with the difference of the electron density distribution in defects. Temperature dependences of the zero-phonon lines widths and shifts have been measured. It has been determined that both widths and shifts grow faster with the increase of a temperature for the defects transitions with the lesser Huang-Rhys parameters. Phonons lifetimes are estimated from the experimental data.

Zero-phonon lines and electron–phonon interaction characteristics of near-surface layer radiation color centers in lithium fluoride

International Nuclear Information System (INIS)

Voitovich, A.P.; Kalinov, V.S.; Mudryi, A.V.; Pavlovskii, V.N.; Runets, L.P.; Svitsiankou, I.E.

2016-01-01

Zero-phonon lines have been registered in photoluminescence spectra of near-surface layer radiation color centers in lithium fluoride nanocrystals. They have been assigned to transitions of the definite types centers. The frequencies of phonons participating in the transitions of the different type centers located both in the near-surface layer and in the crystal bulk have been measured and compared. The Huang-Rhys parameters for the transitions of these centers have been determined. It has been found that the Huang-Rhys parameters for the studied transitions in the near-surface layer centers of the certain composition are less than for those in the crystal bulk centers of the same composition. This feature is connected with the difference of the electron density distribution in defects. Temperature dependences of the zero-phonon lines widths and shifts have been measured. It has been determined that both widths and shifts grow faster with the increase of a temperature for the defects transitions with the lesser Huang-Rhys parameters. Phonons lifetimes are estimated from the experimental data.

Distilling two-center-interference information during tunneling of aligned molecules with orthogonally polarized two-color laser fields

Science.gov (United States)

Gao, F.; Chen, Y. J.; Xin, G. G.; Liu, J.; Fu, L. B.

2017-12-01

When electrons tunnel through a barrier formed by the strong laser field and the two-center potential of a diatomic molecule, a double-slit-like interference can occur. However, this interference effect can not be probed directly right now, as it is strongly coupled with other dynamical processes during tunneling. Here, we show numerically and analytically that orthogonally polarized two-color (OTC) laser fields are capable of resolving the interference effect in tunneling, while leaving clear footprints of this effect in photoelectron momentum distributions. Moreover, this effect can be manipulated by changing the relative field strength of OTC fields.

Luminescence of color centers in MgF2 crystals

International Nuclear Information System (INIS)

Vakhidov, Sh.A.; Nuritdinov, I.; Musaeva, M.A.

1999-01-01

The photoluminescence characteristics of the proper radiation color centers of the MgF 2 crystals are studied. The samples were irradiated by the 60 Co source γ-rays up to the dose 10 7 Gy. The bands with the maxima in the area of 420, 460, 550 and 620 nm were identified, which are excited correspondingly in the bands with the maxima of 370, 320, 410 and 480 nm

Color Fundus Photography versus Fluorescein Angiography in Identification of the Macular Center and Zone in Retinopathy of Prematurity

Science.gov (United States)

Patel, Samir N.; Klufas, Michael A.; Ryan, Michael C.; Jonas, Karyn E.; Ostmo, Susan; Martinez-Castellanos, Maria Ana; Berrocal, Audina M.; Chiang, Michael F.; Chan, R.V. Paul

2016-01-01

Purpose To examine the utility of fluorescein angiography (FA) in identification of the macular center and the diagnosis of zone in patients with retinopathy of prematurity (ROP). Design Validity and reliability analysis of diagnostic tools Methods 32 sets (16 color fundus photographs; 16 color fundus photographs paired with the corresponding FA) of wide-angle retinal images obtained from 16 eyes of eight infants with ROP were compiled on a secure web site. 9 ROP experts (3 pediatric ophthalmologists; 6 vitreoretinal surgeons) participated in the study. For each image set, experts identified the macular center and provided a diagnosis of zone. Main Outcome Measures (1) Sensitivity and specificity of zone diagnosis (2) “Computer facilitated diagnosis of zone,” based on precise measurement of the macular center, optic disc center, and peripheral ROP. Results Computer facilitated diagnosis of zone agreed with the expert’s diagnosis of zone in 28/45 (62%) cases using color fundus photographs and in 31/45 (69%) cases using FA. Mean (95% CI) sensitivity for detection of zone I by experts as compared to a consensus reference standard diagnosis when interpreting the color fundus images alone versus interpreting the color fundus photographs and FA was 47% (35.3% – 59.3%) and 61.1% (48.9% – 72.4%), respectively, (t(9) ≥ (2.063), p = 0.073). Conclusions There is a marginally significant difference in zone diagnosis when using color fundus photographs compared to using color fundus photographs and the corresponding fluorescein angiograms. There is inconsistency between traditional zone diagnosis (based on ophthalmoscopic exam and image review) compared to a computer-facilitated diagnosis of zone. PMID:25637180

Many-electron states of the N2 and N3 color centers in diamond: A first- principles and many-body study

Energy Technology Data Exchange (ETDEWEB)

Babamoradi, Mohsen, E-mail: babamoradi@iust.ac.ir [Department of Physics, Iran University of Science and Technology, Narmak,16846-13114 Tehran (Iran, Islamic Republic of); Asgari, Sussan [Department of Physics, Iran University of Science and Technology, Narmak,16846-13114 Tehran (Iran, Islamic Republic of); Ranjbar, Ahmad [Computational Materials Science Research Team, RIKEN Advanced Institute for Computational Science, Kobe, Hyogo 650-0047 (Japan); Belosludov, Rodion V. [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan); Yunoki, Seiji [Computational Materials Science Research Team, RIKEN Advanced Institute for Computational Science, Kobe, Hyogo 650-0047 (Japan); Computational Condensed Matter Physics Laboratory, RIKEN, Wako, Saitama 351-0198 (Japan); Computational Quantum Matter Research Team, RIKEN Center for Emergent Matter Science, Wako, Saitama 351-0198 (Japan)

2017-01-15

A new model is applied to calculate the many-body properties of the neutral N3 color center in diamond. This model is based on the first-principles density functional theory (DFT) and cluster method, which is combined with the generalized Hubbard model. In contrast to the previous models for N3 centers, our model does not require the configuration interaction (CI) and molecular orbital (MO) techniques. The N3 defect in diamond is simulated with an empty site next to three substitutional nitrogen atoms in the center of a hydrogen-terminated diamond cluster. The method is shown to be highly accurate for describing the symmetries and spin properties of the ground state and the first dipole-allowed excited state for the N3 center. We obtain the transition energy as 412 nm for the first dipole-allowed transition, which is in good agreement with the corresponding experimental value as 415 nm. We assigned the dipole-allowed transition between the first and second excited states as the N2 optical peak, and evaluated the N2 optical peak to be 463 nm, which is close to the experimental value as 478 nm.

Color electron microprobe cathodoluminescence of Bishunpur meteorite compared with the traditional optical microscopy method

Directory of Open Access Journals (Sweden)

Amanda Araujo Tosi

Full Text Available Abstract Cathodoluminescence (CL imaging is an outstanding method for sub classification of Unequilibrated Ordinary Chondrites (UOC - petrological type 3. CL can be obtained by several electron beam apparatuses. The traditional method uses an electron gun coupled to an optical microscope (OM. Although many scanning electron microscopes (SEM and electron microprobes (EPMA have been equipped with a cathodoluminescence, this technique was not fully explored. Images obtained by the two methods differ due to a different kind of signal acquisition. While in the CL-OM optical photography true colors are obtained, in the CL-EPMA the results are grayscale monochromatic electronic signals. L-RGB filters were used in the CL-EPMA analysis in order to obtain color data. The aim of this work is to compare cathodoluminescence data obtained from both techniques, optical microscope and electron microprobe, on the Bishunpur meteorite classified as LL 3.1 chondrite. The present study allows concluding that 20 KeV and 7 nA is the best analytical condition at EPMA in order to test the equivalence between CL-EPMA and CL-OM colour results. Moreover, the color index revealed to be a method for aiding the study of the thermal metamorphism, but it is not definitive for the meteorite classification.

A simple methodology for obtaining X-ray color images in scanning electron microscopy

International Nuclear Information System (INIS)

Veiga, M.M. da; Pietroluongo, L.R.V.

1985-01-01

A simple methodology for obtaining at least 3 elements X-ray images in only one photography is described. The fluorescent X-ray image is obtained from scanning electron microscopy with energy dispersion analysis system. The change of detector analytic channels, color cellophane foils and color films are used sequentially. (M.C.K.) [pt

The three-electron bond =Sicenter of pre-darkened ytterbium-doped silica

DEFF Research Database (Denmark)

Mattsson, Kent Erik

2013-01-01

The formation and bleaching of color centers during annealing of pre-darkened ytterbium-doped silica fibers is modeled by three-electron bond (TEB) = Si... bonds is described in terms of a Markov statistical model with state change set by Bose-Einstein phonon statistics. The center hold one terminal and four active states with activation energies for transitions among these found to match bond energies of molecular oxygen in ionic character bonds of 1...... and 1½ bond order. Experimentally observed in- and decrease in absorption during ramp and isothermal annealing of pre-darkened ytterbium co-doped silica fibers are hereby matched by a set of = Si

Simulation of multicomponent light source for optical-electronic system of color analysis objects

Science.gov (United States)

Peretiagin, Vladimir S.; Alekhin, Artem A.; Korotaev, Valery V.

2016-04-01

Development of lighting technology has led to possibility of using LEDs in the specialized devices for outdoor, industrial (decorative and accent) and domestic lighting. In addition, LEDs and devices based on them are widely used for solving particular problems. For example, the LED devices are widely used for lighting of vegetables and fruit (for their sorting or growing), textile products (for the control of its quality), minerals (for their sorting), etc. Causes of active introduction LED technology in different systems, including optical-electronic devices and systems, are a large choice of emission color and LED structure, that defines the spatial, power, thermal and other parameters. Furthermore, multi-element and color devices of lighting with adjustable illumination properties can be designed and implemented by using LEDs. However, devices based on LEDs require more attention if you want to provide a certain nature of the energy or color distribution at all the work area (area of analysis or observation) or surface of the object. This paper is proposed a method of theoretical modeling of the lighting devices. The authors present the models of RGB multicomponent light source applied to optical-electronic system for the color analysis of mineral objects. The possibility of formation the uniform and homogeneous on energy and color illumination of the work area for this system is presented. Also authors showed how parameters and characteristics of optical radiation receiver (by optical-electronic system) affect on the energy, spatial, spectral and colorimetric properties of a multicomponent light source.

Size-controlled fluorescent nanodiamonds: A facile method of fabrication and color-center counting

KAUST Repository

Mahfouz, Remi

2013-01-01

We present a facile method for the production of fluorescent diamond nanocrystals (DNCs) of different sizes and efficiently quantify the concentration of emitting defect color centers (DCCs) of each DNC size. We prepared the DNCs by ball-milling commercially available micrometer-sized synthetic (high pressure, high temperature (HPHT)) diamonds and then separated the as-produced DNCs by density gradient ultracentrifugation (DGU) into size-controlled fractions. A protocol to enhance the uniformity of the nitrogen-vacancy (NV) centers in the diamonds was devised by depositing the DNCs as a dense monolayer on amino-silanized silicon substrates and then subjecting the monolayer to He+ beam irradiation. Using a standard confocal setup, we analyzed the average number of NV centers per crystal, and obtained a quantitative relationship between the DNC particle size and the NV number per crystal. This relationship was in good agreement with results from previous studies that used more elaborate setups. Our findings suggest that nanocrystal size separation by DGU may be used to control the number of defects per nanocrystal. The efficient approaches described herein to control and quantify DCCs are valuable to researchers as they explore applications for color centers and new strategies to create them. © 2013 The Royal Society of Chemistry.

The relationship between past caries experience and tooth color determined by an opto-electronic method.

Science.gov (United States)

Kerosuo, E; Kolehmainen, L

1982-01-01

The susceptibility of a tooth to dental caries has been proposed to depend on tooth color. So far there has, however, been no reliable method for tooth color determination. The aims of this study were to evaluate the reliability of an opto-electronic method and to examine the relationship between tooth color and past caries experience. The color of upper right central incisors of 64 school-children was determined using an opto-electronic tri-stimulus color comparator. The intra- and interexaminer reliability of the method was evaluated in vitro and in vivo being 85% and 83%, respectively. To assess the past caries experience the DMFS-index was calculated. Oral hygiene and dietary habits were also assessed. No significant difference in DMFS scores was obtained between the 'white teeth' group and the 'yellow teeth' group. The conclusion is, that the practical importance of possible colorrelated differences in caries resistance is negligible due to the multifaceted nature of dental caries.

Multiphoton-Excited Fluorescence of Silicon-Vacancy Color Centers in Diamond

Science.gov (United States)

Higbie, J. M.; Perreault, J. D.; Acosta, V. M.; Belthangady, C.; Lebel, P.; Kim, M. H.; Nguyen, K.; Demas, V.; Bajaj, V.; Santori, C.

2017-05-01

Silicon-vacancy color centers in nanodiamonds are promising as fluorescent labels for biological applications, with a narrow, nonbleaching emission line at 738 nm. Two-photon excitation of this fluorescence offers the possibility of low-background detection at significant tissue depth with high three-dimensional spatial resolution. We measure the two-photon fluorescence cross section of a negatively charged silicon vacancy (Si -V- ) in ion-implanted bulk diamond to be 0.74 (19 )×10-50 cm4 s /photon at an excitation wavelength of 1040 nm. Compared to the diamond nitrogen-vacancy center, the expected detection threshold of a two-photon excited Si -V center is more than an order of magnitude lower, largely due to its much narrower linewidth. We also present measurements of two- and three-photon excitation spectra, finding an increase in the two-photon cross section with decreasing wavelength, and we discuss the physical interpretation of the spectra in the context of existing models of the Si -V energy-level structure.

Multi-color imaging of fluorescent nanodiamonds in living HeLa cells using direct electron-beam excitation.

Science.gov (United States)

Nawa, Yasunori; Inami, Wataru; Lin, Sheng; Kawata, Yoshimasa; Terakawa, Susumu; Fang, Chia-Yi; Chang, Huan-Cheng

2014-03-17

Multi-color, high spatial resolution imaging of fluorescent nanodiamonds (FNDs) in living HeLa cells has been performed with a direct electron-beam excitation-assisted fluorescence (D-EXA) microscope. In this technique, fluorescent materials are directly excited with a focused electron beam and the resulting cathodoluminescence (CL) is detected with nanoscale resolution. Green- and red-light-emitting FNDs were employed for two-color imaging, which were observed simultaneously in the cells with high spatial resolution. This technique could be applied generally for multi-color immunostaining to reveal various cell functions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ultrathin Nanocrystalline Diamond Films with Silicon Vacancy Color Centers via Seeding by 2 nm Detonation Nanodiamonds.

Science.gov (United States)

Stehlik, Stepan; Varga, Marian; Stenclova, Pavla; Ondic, Lukas; Ledinsky, Martin; Pangrac, Jiri; Vanek, Ondrej; Lipov, Jan; Kromka, Alexander; Rezek, Bohuslav

2017-11-08

Color centers in diamonds have shown excellent potential for applications in quantum information processing, photonics, and biology. Here we report chemical vapor deposition (CVD) growth of nanocrystalline diamond (NCD) films as thin as 5-6 nm with photoluminescence (PL) from silicon-vacancy (SiV) centers at 739 nm. Instead of conventional 4-6 nm detonation nanodiamonds (DNDs), we prepared and employed hydrogenated 2 nm DNDs (zeta potential = +36 mV) to form extremely dense (∼1.3 × 10 13 cm -2 ), thin (2 ± 1 nm), and smooth (RMS roughness < 0.8 nm) nucleation layers on an Si/SiO x substrate, which enabled the CVD growth of such ultrathin NCD films in two different and complementary microwave (MW) CVD systems: (i) focused MW plasma with an ellipsoidal cavity resonator and (ii) pulsed MW plasma with a linear antenna arrangement. Analytical ultracentrifuge, infrared and Raman spectroscopies, atomic force microscopy, and scanning electron microscopy are used for detailed characterization of the 2 nm H-DNDs and the nucleation layer as well as the ultrathin NCD films. We also demonstrate on/off switching of the SiV center PL in the NCD films thinner than 10 nm, which is achieved by changing their surface chemistry.

Optical properties of T-centers under gamma irradiation

CERN Document Server

Polosan, S; Dragusin, M; Topa, V

2003-01-01

Electrolytic coloring of KCl:Pb crystals, leads to formation of negative metal ions with intense emission in the infrared region. These new color centers were named T centers; their most probable configuration could be Pb sub 2 sup 2 sup - , due to the lack of EPR or DCM signals. In order to destroy these structures, the crystals were irradiated with gamma-rays at high doses. The results were the detachment of the electrons from T centers and the appearance of Pb sup 2 sup + - ions. The possibility cannot be excluded of the existence of Pb sup + and Pb sup 0 centers in the samples, because these centers do not exhibit any optical properties on this spectral region. (authors)

Electronic structure of deep impurity centers in silicon

International Nuclear Information System (INIS)

Oosten, A.B. van.

1989-01-01

This thesis reports an experimental study of deep level impurity centers in silicon, with much attention for theoretical interpretation of the data. A detailed picture of the electronic structure of several centers was obtained by magnetic resonance techniques, such as electron paramagnetic resonance (EPR), electron-nuclear double resonance (ENDOR) and field scanned ENDOR (FSE). The thesis consists of two parts. The first part deals with chalcogen (sulfur, selenium and tellurium) related impurities, which are mostly double donors. The second part is about late transition metal (nickel, palladium and platinum) impurities, which are single (Pd,Pt) or double (Ni) acceptor centers. (author). 155 refs.; 51 figs.; 23 tabs

Study of the fluorescence blinking behavior of single F2 color centers in LiF crystal

International Nuclear Information System (INIS)

Boichenko, S V; Koenig, K; Zilov, S A; Dresvianskiy, V P; Rakevich, A L; Kuznetsov, A V; Bartul, A V; Martynovich, E F; Voitovich, A P

2014-01-01

Using confocal fluorescence microscopy technique, we observed experimentally the luminescence of single F 2 color centers in LiF crystal. It is disclosed that the fluorescence shows blinking behavior. It is shown that this phenomenon is caused by the F 2 center reorientation occurring during the experiment. The ratio of luminescence intensities of differently oriented centers is assessed theoretically for two different experiment configurations. The calculated ratios are in fine agreement with experimental result

Effect of Pre-Irradiation Annealing and Laser Modification on the Formation of Radiation-Induced Surface Color Centers in Lithium Fluoride

Science.gov (United States)

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.

Device for the radiation centering at electron emitters

International Nuclear Information System (INIS)

Panzer, S.; Ardenne, T. von; Jessat, K.; Bahr, G.

1985-01-01

The invention has been directed at a device for a simplified and reliable centering of electron beams at electron emitters in particular for welding and thermal surface modifications. The electron beam has been focussed relatively to an electron-optical lens. A movable masked electron detector has been arranged at the electron beam deflection plane. The electron detector is connected with an electronic data evaluation equipment

RGB color coded images in scanning electron microscopy of biological surfaces

Czech Academy of Sciences Publication Activity Database

Kofroňová, Olga; Benada, Oldřich

2017-01-01

Roč. 61, č. 3 (2017), s. 349-352 ISSN 0001-723X R&D Projects: GA MŠk(CZ) LO1509; GA ČR(CZ) GA16-20229S Institutional support: RVO:61388971 Keywords : Biological surfaces * Color image s * Scanning electron microscopy Subject RIV: EE - Microbiology, Virology OBOR OECD: Microbiology Impact factor: 0.673, year: 2016

Electrolytic coloration of air-grown sodium fluoride crystals

International Nuclear Information System (INIS)

Gu Hongen; Han Li; Song Cuiying; Guo Meili; Wang Na

2007-01-01

Air-grown sodium fluoride crystals were colored electrolytically by using a pointed cathode at various temperatures and electric field strengths, which should mainly benefit appropriate coloration temperatures and electric field strengths. O 2 - , F, M, N 1 , N 2 color centers and O 2- -F + complexes were produced in the colored crystals. Current-time curves for the electrolytic colorations were given, and activation energy for the V color center migration was determined. The formation of the color centers was explained

Content-Based Image Retrieval Benchmarking: Utilizing color categories and color distributions

NARCIS (Netherlands)

van den Broek, Egon; Kisters, Peter M.F.; Vuurpijl, Louis G.

From a human centered perspective three ingredients for Content-Based Image Retrieval (CBIR) were developed. First, with their existence confirmed by experimental data, 11 color categories were utilized for CBIR and used as input for a new color space segmentation technique. The complete HSI color

Momentum spectra of electrons rescattered from rare-gas targets following their extraction by one- and two-color femtosecond laser pulses

International Nuclear Information System (INIS)

Ray, D.; Chen Zhangjin; De, S.; Cao, W.; Le, A. T.; Lin, C. D.; Cocke, C. L.; Litvinyuk, I. V.; Kling, M. F.

2011-01-01

We have used velocity-map imaging to measure the three-dimensional momenta of electrons rescattered from Xe and Ar following the liberation of the electrons from these atoms by 45 fs, 800 nm intense laser pulses. Strong structure in the rescattering region is observed in both angle and energy, and is interpreted in terms of quantitative rescattering (QRS) theory. Momentum images have also been taken with two-color (800 nm + 400 nm) pulses on Xe targets. A strong dependence of the spectra on the relative phase of the two colors is observed in the rescattering region. Interpretation of the phase dependence using both QRS theory and a full solution to the time-dependent Schroedinger equation shows that the rescattered electrons provide a much more robust method for determining the relative phase of the two colors than do the direct electrons.

Independent center, independent electron approximation for dynamics of molecules and clusters

International Nuclear Information System (INIS)

McGuire, J.H.; Straton, J.C.; Wang, J.; Wang, Y.D.; Weaver, O.L.; Corchs, S.E.; Rivarola, R.D.

1996-01-01

A formalism is developed for evaluating probabilities and cross sections for multiple-electron transitions in scattering of molecules and clusters by charged collision partners. First, the molecule is divided into subclusters each made up of identical centers (atoms). Within each subcluster coherent scattering from identical centers may lead to observable phase terms and a geometrical structure factor. Then, using a mean field approximation to describe the interactions between centers we obtain A I ∼ summation k product ke iδ k I A Ik . Second, the independent electron approximation for each center may be obtained by neglecting the correlation between electrons in each center. The probability amplitude for each center is then a product of single electron transition probability amplitudes, a Ik i , i.e. A Ik ≅ product iaik i . Finally, the independent subcluster approximation is introduced by neglecting the interactions between different subclusters in the molecule or cluster. The total probability amplitude then reduces to a simple product of amplitudes for each subcluster, A≅ product IAI . Limitations of this simple approximation are discussed. copyright 1996 American Institute of Physics

National Center for Electron Microscopy users' guide

International Nuclear Information System (INIS)

1987-01-01

The National Center for Electron Microscopy (NCEM) in the Materials and Molecular Research Division of the Lawrence Berkeley Laboratory is a high voltage electron microscope facility for ultra-high resolution or dynamic in-situ studies. This guide describes the instruments and their specifications, support instrumentation, and user policies. Advice as to travel and accommodations is provided in the guide. (FI)

Colored Contact Lens Dangers

Medline Plus

Full Text Available ... Education Center Oculofacial Plastic Surgery Center Laser Surgery Education Center Redmond Ethics Center Global Ophthalmology Guide Eye Health ... Leer en Español: Peligros asociados con los lentes de contacto de color Sep. 26, ...

Soft X-ray imaging by optically stimulated luminescence from color centers in lithium fluoride

Energy Technology Data Exchange (ETDEWEB)

Bonfigli, F. [ENEA, C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy)], E-mail: bonfigli@frascati.enea.it; Almaviva, S.; Baldacchini, G.; Bollanti, S.; Flora, F.; Lai, A.; Montereali, R.M. [ENEA, C.R. Frascati, Via E. Fermi, 45, 00044 Frascati (Rome) (Italy); Nichelatti, E. [ENEA, C.R. Casaccia, Via Anguillarese 301, 00060 S.Maria di Galeria (Rome) (Italy); Tomassetti, G.; Ritucci, A.; Reale, L. [Universita de L' Aquila e INFN, Dip. di Fisica, Coppito, L' Aquila (Italy); Faenov, A. Ya.; Pikuz, T.A. [MISDC of VNIIFTRI Mendeleevo, Moscow region, 141570 (Russian Federation); Larciprete, R. [ISC-CNR, Sezione Montelibretti, Via Salaria, Km. 29.3, 00016 Monterotondo Scalo (Rome) (Italy); Gregoratti, L.; Kiskinova, M. [Sincrotrone Trieste, S. S. 14, Km. 163.5, 34012 Basovizza (TS) (Italy)

2007-07-15

An innovative X-ray imaging detector based on Optically Stimulated Luminescence from color centers in lithium fluoride is presented. Regular photoluminescent patterns produced on LiF samples by different intense X-ray sources, like synchrotrons, laser plasma sources and a capillary discharge laser have been investigated by a Confocal Laser Scanning Microscope. The use of a LiF-based imaging plate for X-ray microscopy is also discussed showing microradiographies of small animals.

Study of the spectral and energy characteristics of lasing in the green spectral region by lithium fluoride with radiation color centers

Energy Technology Data Exchange (ETDEWEB)

Voitovich, A.P.; Kalinov, V.S.; Mikhnov, S.A.; Ovseichuk, S.I.

1987-06-01

The spectral and energy characteristics of lasers utilizing lithium fluoride with F2 and F3(+) color centers in transverse and longitudinal pumping schemes are studied. The feasibility of obtaining stable narrow-band radiation in the 510-570 nm range using a selective resonator is demonstrated. Consideration is given to the effect of lithium-fluoride crystal processing by excimer laser radiation at a wavelength of 308 nm on the spectroscopic and lasing characteristics of the F3(+) color center. After this processing, the laser efficiency in the green spectral region increases by more than a factor of two (reaching an efficiency of 14 percent). 7 references.

Studies on the radicidation of natural food colorants. Effects of electron energy (accelerating voltages) and dose rate of ionizing radiation on functional properties of beet red colorant

International Nuclear Information System (INIS)

Higashimura, Yutaka; Tada, Mikiro; Furuta, Masakazu

2003-01-01

In order to the practical use of radicidation of beet red, natural food colorant with low heat stability and high possibility of microbe contamination, we studied on the energy dependency and dose rate effect for the influence on functional properties of the beet red colorant. For the elucidation of energy dependency, the γ-ray (1.33 MeV) and electron beams with different accelerating voltages (0.75, 1, 2.5, 5 and 10 MeV) were used. The dose rate effect was studied under the different dose rate by using γ-ray (0.723, 1.91 and 4.55 kGy/h) and electron beams with accelerating voltage of 10 MeV (1.0 x 10 3 , 2.6 x 10 3 , 7.0 x 10 3 , 7.0 x 10 3 , 2.0 x 10 4 and 5.0 x 10 4 kGy/h). The results obtained in this study showed that regardless of these energy and dose rate, the functional properties of the beet red colorant were little affected by irradiation less than 25 kGy of ionizing radiations. (author)

Color, flavor, and sensory characteristics of gamma-irradiated salted and fermented anchovy sauce[Gamma irradiation; Fermented anchovy; Color; Flavor compounds; Electronic nose; Sensory evaluation

Energy Technology Data Exchange (ETDEWEB)

Kim, J.H.; Ahn, Hyun Joo; Yook, Hong Sun; Kim, Kyong Soo; Rhee, Moon Soo; Ryu, Gi Hyung; Byun, Myung Woo E-mail: mwbyun@kaeri.re.kr

2004-02-01

Color, flavor, and sensory characteristics of irradiated salted and fermented anchovy sauce were investigated. The filtrate of salted and fermented anchovy was irradiated at 0, 2.5, 5, 7.5, and 10 kGy. After irradiation, Hunter's color values were increased, however, the color values were gradually decreased in all samples during storage. Amount of the aldehydes, esters, ketones, S-containing compounds, and the other groups were increased up to 7.5 kGy irradiation, then decreased at 10 kGy (P<0.05), while the alcohols and furan groups were increased by irradiation. Different odor patterns were observed among samples using electronic nose system analysis. Gamma-irradiated samples showed better sensory score and the quality was sustained during storage. In conclusion, gamma irradiation of salted and fermented anchovy sauce could improve its sensory quality by reducing typical fishy smell.

Nonvolatile two-step, two-color holography with continuous-wave lights for both congruent and near-stoichiometric LiNbO3:Fe

International Nuclear Information System (INIS)

Shen Yan; Zhang Guoquan; Fu Bo; Xu Qingjun; Xu Jingjun

2004-01-01

We have studied theoretically the steady-state nonvolatile two-step, two-color holographic recording performance for both the congruent and the near-stoichiometric LiNbO 3 :Fe based on the two-center model (the deep-trap and the shallow-trap centers are Fe 2+ /Fe 3+ and Nb Li 4+ /Nb Li 5+ , respectively). The results show that the direct electron exchange between the Fe 2+ /Fe 3+ centers and the Nb Li 4+ /Nb Li 5+ centers due to the tunneling effect dominates the charge-transfer process during the nonvolatile two-step, two-color holography and determines the two-step, two-color holography performance in LiNbO 3 :Fe. We have further studied the effects of the crystal stoichiometry on the performance of the two-step, two-color holography. It is shown that, as far as the total space-charge field is considered, the nonvolatile two-step, two-color holography performance in the near-stoichiometric LiNbO 3 :Fe is much better than that in the congruent LiNbO 3 :Fe within the intensity range reachable by the continuous-wave lights

Using clinical simulation centers to test design interventions: a pilot study of lighting and color modifications.

Science.gov (United States)

Gray, Whitney Austin; Kesten, Karen S; Hurst, Stephen; Day, Tama Duffy; Anderko, Laura

2012-01-01

The aim of this pilot study was to test design interventions such as lighting, color, and spatial color patterning on nurses' stress, alertness, and satisfaction, and to provide an example of how clinical simulation centers can be used to conduct research. The application of evidence-based design research in healthcare settings requires a transdisciplinary approach. Integrating approaches from multiple fields in real-life settings often proves time consuming and experimentally difficult. However, forums for collaboration such as clinical simulation centers may offer a solution. In these settings, identical operating and patient rooms are used to deliver simulated patient care scenarios using automated mannequins. Two identical rooms were modified in the clinical simulation center. Nurses spent 30 minutes in each room performing simulated cardiac resuscitation. Subjective measures of nurses' stress, alertness, and satisfaction were collected and compared between settings and across time using matched-pair t-test analysis. Nurses reported feeling less stressed after exposure to the experimental room than nurses who were exposed to the control room (2.22, p = .03). Scores post-session indicated a significant reduction in stress and an increase in alertness after exposure to the experimental room as compared to the control room, with significance levels below .10. (Change in stress scores: 3.44, p = .069); (change in alertness scores: 3.6, p = .071). This study reinforces the use of validated survey tools to measure stress, alertness, and satisfaction. Results support human-centered design approaches by evaluating the effect on nurses in an experimental setting.

Reduction of Aflatoxins in Apricot Kernels by Electronic and Manual Color Sorting

OpenAIRE

Zivoli, Rosanna; Gambacorta, Lucia; Piemontese, Luca; Solfrizzo, Michele

2016-01-01

The efficacy of color sorting on reducing aflatoxin levels in shelled apricot kernels was assessed. Naturally-contaminated kernels were submitted to an electronic optical sorter or blanched, peeled, and manually sorted to visually identify and sort discolored kernels (dark and spotted) from healthy ones. The samples obtained from the two sorting approaches were ground, homogenized, and analysed by HPLC-FLD for their aflatoxin content. A mass balance approach was used to measure the distributi...

Calibration of a two-color soft x-ray diagnostic for electron temperature measurement

Energy Technology Data Exchange (ETDEWEB)

Reusch, L. M., E-mail: lmmcguire@wisc.edu; Den Hartog, D. J.; Goetz, J.; McGarry, M. B. [University of Wisconsin - Madison, Madison, Wisconsin 53703 (United States); Franz, P. [Consorzio RFX, Padova (Italy); Stephens, H. D. [University of Wisconsin - Madison, Madison, Wisconsin 53703 (United States); Pierce College Fort Steilacoom, Lakewood, Washington 98498 (United States)

2016-11-15

The two-color soft x-ray (SXR) tomography diagnostic on the Madison Symmetric Torus is capable of making electron temperature measurements via the double-filter technique; however, there has been a 15% systematic discrepancy between the SXR double-filter (SXR{sub DF}) temperature and Thomson scattering (TS) temperature. Here we discuss calibration of the Be filters used in the SXR{sub DF} measurement using empirical measurements of the transmission function versus energy at the BESSY II electron storage ring, electron microprobe analysis of filter contaminants, and measurement of the effective density. The calibration does not account for the TS and SXR{sub DF} discrepancy, and evidence from experiments indicates that this discrepancy is due to physics missing from the SXR{sub DF} analysis rather than instrumentation effects.

Colored Contact Lens Dangers

Medline Plus

Full Text Available ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering buying approved by the ... Service For Advertisers For Media Ophthalmology Job Center © American ...

Electron paramagnetic resonance of the ns1 centers in crystals

International Nuclear Information System (INIS)

Nistor, S.V.; Ursu, I.

1993-05-01

The results of the EPR studies concerning the paramagnetic centers with ns 1 (N=n>2) outer electronic configuration contained in crystals are reviewed. Such centers, with 2 S 1/2 ground state, are produced by electron trapping at impurities of the IB and IIB group or by hole trapping at impurities of the IIIB and IV group of elements. The production and structural properties of such centers consisting of ns 1 ions (atoms) at various sites in the crystal lattice with different configurations of neighbouring defects are discussed in connection with their EPR characteristics. Tables containing the spin Hamiltonian parameters of all ns 1 centers reported in the literature until the end of year 1992 are given. (author). 146 refs, 14 tabs

Center Line Slope Analysis in Two-Dimensional Electronic Spectroscopy

OpenAIRE

?anda, Franti?ek; Perl?k, V?clav; Lincoln, Craig N.; Hauer, J?rgen

2015-01-01

Center line slope (CLS) analysis in 2D infrared spectroscopy has been extensively used to extract frequency?frequency correlation functions of vibrational transitions. We apply this concept to 2D electronic spectroscopy, where CLS is a measure of electronic gap fluctuations. The two domains, infrared and electronic, possess differences: In the infrared, the frequency fluctuations are classical, often slow and Gaussian. In contrast, electronic spectra are subject to fast spectral diffusion and...

Use of Color in Child Care Environments: Application of Color for Wayfinding and Space Definition in Alabama Child Care Environments.

Science.gov (United States)

Read, Marilyn A.

2003-01-01

Compared the use of color in physical design features associated with the exterior and interior designs of 101 child care centers in Alabama. Found that color was evidenced on the exterior of the centers at just over half of the sample. The interior environments had warm colors and bright accents in the setting; however, the majority of centers…

Marshak Lectureship: Vibrational properties of isolated color centers in diamond

Science.gov (United States)

Alkauskas, Audrius

In this talk we review our recent work on first-principles calculations of vibrational properties of isolated defect spin qubits and single photon emitters in diamond. These properties include local vibrational spectra, luminescence lineshapes, and electron-phonon coupling. They are key in understanding physical mechanisms behind spin-selective optical initialization and read-out, quantum efficiency of single-photon emitters, as well as in the experimental identification of as yet unknown centers. We first present the methodology to calculate and analyze vibrational properties of effectively isolated defect centers. We then apply the methodology to the nitrogen-vacancy and the silicon-vacancy centers in diamond. First-principles calculations yield important new insights about these important defects. Work performed in collaboration with M. W. Doherty, A. Gali, E. Londero, L. Razinkovas, and C. G. Van de Walle. Supported by the Research Council of Lithuania (Grant M-ERA.NET-1/2015).

Dynamical nuclear polarization using multi-colour control of color centers in diamond

Energy Technology Data Exchange (ETDEWEB)

Yang, Pengcheng [Huazhong University of Science and Technology, School of Physics, Wuhan (China); Huazhong University of Science and Technology, Center for Quantum Optical Science, Wuhan (China); Plenio, Martin B. [Universitaet Ulm, Institut fuer Theoretische Physik, Ulm (Germany); Universitaet Ulm, Center for Integrated Quantum Science and Technology, Ulm (Germany); Cai, Jianming [Huazhong University of Science and Technology, School of Physics, Wuhan (China); Huazhong University of Science and Technology, Center for Quantum Optical Science, Wuhan (China); Universitaet Ulm, Institut fuer Theoretische Physik, Ulm (Germany); Universitaet Ulm, Center for Integrated Quantum Science and Technology, Ulm (Germany)

2016-12-15

Dynamical nuclear polarization (DNP) transfers the polarization of electron spins at cryogenic temperatures to achieve strong nuclear polarization for applications in nuclear magnetic resonance. Recently introduced approaches employ optical pumping of nitrogen-vacancy (NV) centers in diamond to achieve DNP even at ambient temperatures. In such schemes microwave radiation is used to establish a Hartmann-Hahn condition between the NV electron spin and proximal nuclear spins to facilitate polarization transfer. For a single monochromatic microwave driving field, the Hartmann-Hahn condition cannot be satisfied for an ensemble of NV centers due to inhomogeneous broadening and reduces significantly the overall efficiency of dynamical nuclear polarization using an ensemble of NV centers. Here, we adopt generalized Hartmann-Hahn type dynamical nuclear polarization schemes by applying microwave driving fields with (multiple) time-modulated frequencies. We show that it is possible to enhance the effective coupling between an ensemble of NV center spins with inhomogeneous broadening and nuclear spins, thereby improving significantly the overall efficiency of dynamical nuclear polarization. This approach can also be used to achieve dynamical nuclear polarization of an ensemble of nuclei with a distribution of Larmor frequencies, which would be helpful in magnetic resonance spectroscopy using a single NV spin sensor. (orig.)

Electron-mediating Cu(A) centers in proteins

DEFF Research Database (Denmark)

Epel, Boris; Slutter, Claire S; Neese, Frank

2002-01-01

High field (W-band, 95 GHz) pulsed electron-nuclear double resonance (ENDOR) measurements were carried out on a number of proteins that contain the mixed-valence, binuclear electron-mediating Cu(A) center. These include nitrous oxide reductase (N(2)OR), the recombinant water-soluble fragment...... of subunit II of Thermus thermophilus cytochrome c oxidase (COX) ba(3) (M160T9), its M160QT0 mutant, where the weak axial methionine ligand has been replaced by a glutamine, and the engineered "purple" azurin (purpAz). The three-dimensional (3-D) structures of these proteins, apart from the mutant, are known...... indicates differences in the positions of the imidazole rings relative to the Cu(2)S(2) core. Comparison of the spectral features of the weakly coupled protons of M160QT0 with those of the other investigated proteins shows that they are very similar to those of purpAz, where the Cu(A) center is the most...

Accumulation patterns of proper point defects in thermo-regulating coatings based on ZnO for space vehicles under electron irradiation

International Nuclear Information System (INIS)

Mikhajlov, M.M.; Sharafutdinova, V.V.

1998-01-01

The expansion of the band of the induced absorption of zinc oxide powders and thermo-regulating coatings based on ZnO for space vehicles is carried out after the 30 keV electron irradiation. Singularities of the growth of the intensity of individual components as a function of the accelerated electron flow are studied. It is found that power and exponential dependences with one or two components are characteristic for different color centers and different thermo-regulating coatings. The kinetics of the accumulation of free electrons is characterized by the maximum value of the electron flows at which the generation of color centers on pre-radiation defects is realized by the radiolysis of the pigment lattice

Electrolytic coloration and spectral properties of hydroxyl-doped potassium chloride single crystals

International Nuclear Information System (INIS)

Gu Hongen; Wu Yanru

2011-01-01

Hydroxyl-doped potassium chloride single crystals are colored electrolytically at various temperatures and voltages using a pointed cathode and a flat anode. Characteristic OH - spectral band is observed in the absorption spectrum of uncolored single crystal. Characteristic O - , OH - , U, V 2 , V 3 , O 2- -V a + , F, R 2 and M spectral bands are observed simultaneously in absorption spectra of colored single crystals. Current-time curve for electrolytic coloration of hydroxyl-doped potassium chloride single crystal and its relationship with electrolytic coloration process are given. Production and conversion of color centers are explained. - Highlights: → Expanded the traditional electrolysis method. → Hydroxyl-doped potassium chloride crystals were colored electrolytically for the first time. → Useful V, F and F-aggregate color centers were produced in colored crystals. → V color centers were produced directly and F and F-aggregate color centers indirectly.

Laser-evoked coloration in polymers

International Nuclear Information System (INIS)

Zheng, H.Y.; Rosseinsky, David; Lim, G.C.

2005-01-01

Laser-evoked coloration in polymers has long been a major aim of polymer technology for potential applications in product surface decoration, marking personalised images and logos. However, the coloration results reported so far were mostly attributed to laser-induced thermal-chemical reactions. The laser-irradiated areas are characterized with grooves due to material removal. Furthermore, only single color was laser-induced in any given polymer matrix. To induce multiple colors in a given polymer matrix with no apparent surface material removal is most desirable and challenging and may be achieved through laser-induced photo-chemical reactions. However, little public information is available at present. We report that two colors of red and green have been produced on an initially transparent CPV/PVA samples through UV laser-induced photo-chemical reactions. This is believed the first observation of laser-induced multiple-colors in the given polymer matrix. It is believed that the colorants underwent photo-effected electron transfer with suitable electron donors from the polymers to change from colorless bipyridilium Bipm 2+ to the colored Bipm + species. The discovery may lead to new approaches to the development of laser-evoked multiple coloration in polymers

Science Centers in the Electronic Age: Are We Doomed?

Science.gov (United States)

Russell, Robert L., Ed.; West, Robert M., Ed.

1996-01-01

This issue is a debate-discussion concerning science centers in the electronic age. The articles are based on presentations made at the Science Center World Congress (1st, Heureka, Finland, June 13-17, 1996). The four articles are: (1) "Lessons from Laboratorio dell'Immaginario Scientifico" (Andrea Bandelli); (2) "The Doom-Shaped Thing in the…

Confocal fluorescence microscopy investigation of visible emitting defects induced by electron beam lithography in LIF films

International Nuclear Information System (INIS)

Montereali, R. M.; Bigotta, S.; Pace, A.; Piccinini, M.; Burattini, E.; Grilli, A.; Raco, A.; Giammatteo, M.; L'Aquila Univ., L'Aquila; Picozzi, P.; Santucci, S.; L'Aquila Univ., L'Aquila

2000-01-01

Low energy electron irradiation of lithium fluoride (LiF), in the form of bulk crystals and films, gives rise to the stable formation of primary F defects and aggregated color centers in a thin layer located at the surface of the investigated material. For the first time a confocal light scanning microscope (CLSM) in fluorescence mode was used to reconstruct the depth distribution of efficiently emitting laser active color centers in a stripe-like region induced by 12 and 16 keV electrons on LiF films thermally evaporated on glass. The formation of the F3+ and F2 aggregated defects appears restricted to the electron penetration and proportional to their energy depth profile, as obtained from Monte Carlo simulations [it

Electrolytic coloration and spectral properties of hydroxyl-doped potassium bromide single crystals

International Nuclear Information System (INIS)

Qi, Lan; Song, Cuiying; Gu, Hongen

2013-01-01

Hydroxyl-doped potassium bromide single crystals are colored electrolytically at various temperatures and voltages by using a pointed cathode and a flat anode. The characteristic OH − spectral band is observed in absorption spectrum of uncolored single crystal. The characteristic O − , OH − , U, V 2 , O 2− −V a + , M L1 , F and M spectral bands are observed simultaneously in absorption spectra of colored single crystals. Current–time curve for electrolytic coloration of hydroxyl-doped potassium bromide single crystal and its relationship with electrolytic coloration processes are given. Production and conversion of color centers are explained. - Highlights: ► We expanded the traditional electrolysis method. ► Hydroxyl-doped potassium bromide crystals were colored electrolytically for the first time. ► Useful V, F and F-aggregate color centers were produced in colored crystals. ► V color centers were produced directly and F as well as F-aggregate color centers indirectly.

Optical and microwave control of germanium-vacancy center spins in diamond

Science.gov (United States)

Siyushev, Petr; Metsch, Mathias H.; Ijaz, Aroosa; Binder, Jan M.; Bhaskar, Mihir K.; Sukachev, Denis D.; Sipahigil, Alp; Evans, Ruffin E.; Nguyen, Christian T.; Lukin, Mikhail D.; Hemmer, Philip R.; Palyanov, Yuri N.; Kupriyanov, Igor N.; Borzdov, Yuri M.; Rogers, Lachlan J.; Jelezko, Fedor

2017-08-01

A solid-state system combining a stable spin degree of freedom with an efficient optical interface is highly desirable as an element for integrated quantum-optical and quantum-information systems. We demonstrate a bright color center in diamond with excellent optical properties and controllable electronic spin states. Specifically, we carry out detailed optical spectroscopy of a germanium-vacancy (GeV ) color center demonstrating optical spectral stability. Using an external magnetic field to lift the electronic spin degeneracy, we explore the spin degree of freedom as a controllable qubit. Spin polarization is achieved using optical pumping, and a spin relaxation time in excess of 20 μ s is demonstrated. We report resonant microwave control of spin transitions, and use this as a probe to measure the Autler-Townes effect in a microwave-optical double-resonance experiment. Superposition spin states were prepared using coherent population trapping, and a pure dephasing time of about 19 ns was observed at a temperature of 2.0 K.

Guiding-center equations for electrons in ultraintense laser fields

International Nuclear Information System (INIS)

Moore, J.E.; Fisch, N.J.

1994-01-01

The guiding-center equations are derived for electrons in arbitrarily intense laser fields also subject to external fields and ponderomotive forces. Exhibiting the relativistic mass increase of the oscillating electrons, a simple frame-invariant equation is shown to govern the behavior of the electrons for sufficiently weak background fields and ponderomotive forces. The parameter regime for which such a formulation is valid is made precise, and some predictions of the equation are checked by numerical simulation

Direct detection of light dark matter and solar neutrinos via color center production in crystals

OpenAIRE

Budnik, Ranny; Cheshnovsky, Ori; Slone, Oren; Volansky, Tomer

2018-01-01

We propose a new low-threshold direct-detection concept for dark matter and for coherent nuclear scattering of solar neutrinos, based on the dissociation of atoms and subsequent creation of color center type defects within a lattice. The novelty in our approach lies in its ability to detect single defects in a macroscopic bulk of material. This class of experiments features ultra-low energy thresholds which allows for the probing of dark matter as light as O(10) MeV through nuclear scattering...

A Color-Opponency Based Biological Model for Color Constancy

Directory of Open Access Journals (Sweden)

Yongjie Li

2011-05-01

Full Text Available Color constancy is the ability of the human visual system to adaptively correct color-biased scenes under different illuminants. Most of the existing color constancy models are nonphysiologically plausible. Among the limited biological models, the great majority is Retinex and its variations, and only two or three models directly simulate the feature of color-opponency, but only of the very earliest stages of visual pathway, i.e., the single-opponent mechanisms involved at the levels of retinal ganglion cells and lateral geniculate nucleus (LGN neurons. Considering the extensive physiological evidences supporting that both the single-opponent cells in retina and LGN and the double-opponent neurons in primary visual cortex (V1 are the building blocks for color constancy, in this study we construct a color-opponency based color constancy model by simulating the opponent fashions of both the single-opponent and double-opponent cells in a forward manner. As for the spatial structure of the receptive fields (RF, both the classical RF (CRF center and the nonclassical RF (nCRF surround are taken into account for all the cells. The proposed model was tested on several typical image databases commonly used for performance evaluation of color constancy methods, and exciting results were achieved.

Electronic Commerce Resource Centers. An Industry--University Partnership.

Science.gov (United States)

Gulledge, Thomas R.; Sommer, Rainer; Tarimcilar, M. Murat

1999-01-01

Electronic Commerce Resource Centers focus on transferring emerging technologies to small businesses through university/industry partnerships. Successful implementation hinges on a strategic operating plan, creation of measurable value for customers, investment in customer-targeted training, and measurement of performance outputs. (SK)

Kinetics of the electronic center annealing in Al2O3 crystals

Science.gov (United States)

Kuzovkov, V. N.; Kotomin, E. A.; Popov, A. I.

2018-04-01

The experimental annealing kinetics of the primary electronic F, F+ centers and dimer F2 centers observed in Al2O3 produced under neutron irradiation were carefully analyzed. The developed theory takes into account the interstitial ion diffusion and recombination with immobile F-type and F2-centers, as well as mutual sequential transformation with temperature of three types of experimentally observed dimer centers which differ by net charges (0, +1, +2) with respect to the host crystalline sites. The relative initial concentrations of three types of F2 electronic defects before annealing are obtained, along with energy barriers between their ground states as well as the relaxation energies.

Damping of electron center-of-mass oscillation in ultracold plasmas

International Nuclear Information System (INIS)

Chen, Wei-Ting; Witte, Craig; Roberts, Jacob L.

2016-01-01

Applying a short electric field pulse to an ultracold plasma induces an electron plasma oscillation. This manifests itself as an oscillation of the electron center of mass around the ion center of mass in the ultracold plasma. In general, the oscillation can damp due to either collisionless or collisional mechanisms, or a combination of the both. To investigate the nature of oscillation damping in ultracold plasmas, we developed a molecular dynamics model of the ultracold plasma electrons. Through this model, we found that depending on the neutrality of the ultracold plasma and the size of an applied DC electric field, there are some parameter ranges where the damping is primarily collisional and some primarily collisionless. We conducted experiments to compare the measured damping rate with theory predictions and found them to be in good agreement. Extension of our measurements to different parameter ranges should enable studies for strong-coupling influence on electron-ion collision rates.

Colored Contact Lens Dangers

Medline Plus

Full Text Available ... MD, professor of ophthalmology at Case Western Reserve University in Cleveland. "This is far from the truth." ... use of colored contact lenses , from the U.S. Food and Drug Administration (FDA). Are the colored lenses you are considering buying approved by the ... Service For Advertisers For Media Ophthalmology Job Center © American ...

Attention Filtering in the Design of Electronic Map Displays: A Comparison of Color-Coding, Intensity Coding, and Decluttering Techniques

National Research Council Canada - National Science Library

Yeh, Michelle; Wickens, Christopher D

2000-01-01

In a series of experiments, the use of color-coding, intensity coding, and decluttering were compared order to assess their potential benefits for accessing information from electronic map displays...

Colored cool colorants based on rare earth metal ions

Energy Technology Data Exchange (ETDEWEB)

Sreeram, Kalarical Janardhanan; Aby, Cheruvathoor Poulose; Nair, Balachandran Unni; Ramasami, Thirumalachari [Chemical Laboratory, Central Leather Research Institute, Council of Scientific and Industrial Research, Adyar, Chennai 600 020 (India)

2008-11-15

Colored pigments with high near infrared reflectance and not based on toxic metal ions like cadmium, lead and cobalt are being sought as cool colorants. Through appropriate doping two pigments Ce-Pr-Mo and Ce-Pr-Fe have been developed to offer a reddish brown and reddish orange color, respectively. These pigments have been characterized and found to be highly crystalline with an average size of 300 nm. A shift in band gap energy from 2.21 to 2.18 eV has been observed when Li{sub 2}CO{sub 3} was used as a mineralizer. Scanning electron microscope-energy dispersive X-ray analysis (SEM-EDAX) measurement indicate a uniform grind shape and distribution of metal ion, with over 65% reflectance in the NIR region, these pigments can well serve as cool colorants. (author)

Effect of the melting conditions on the properties of radiation color centers in lanthanum phosphate glasses

Energy Technology Data Exchange (ETDEWEB)

Karapetyan, G.O.; Rusan, V.V.; Yashchurzhinskaya, O.A.

1986-01-01

The authors investigate the spatial effects of ionizing radiation on the radiation processes in phosphate glasses to make a comparative estimate of the radiation yield from the radiation color centers (RCC) of different types. A study is made of their behavior under thermal decoloration. The results of a comparison of the integrated intensities of the ESR signal from trapping centers are given. The ESR spectrum of the glasses are presented--one differs slightly from the others. On the basis of the result of processing the ESR and optical spectra of gamma-irradiated lanthanum phosphate glasses synthesized under various conditions, the radiation yield of the RCC and the behavior of the intensity of their absorption under thermodecoloration are significantly affected by the conditions of synthesis of the glass.

Memory and neural networks on the basis of color centers in solids.

Science.gov (United States)

Winnacker, Albrecht; Osvet, Andres

2009-11-01

Optical data recording is one of the most widely used and efficient systems of memory in the non-living world. The application of color centers in this context offers not only systems of high speed in writing and read-out due to a high degree of parallelism in data handling but also a possibility to set up models of neural networks. In this way, systems with a high potential for image processing, pattern recognition and logical operations can be constructed. A limitation to storage density is given by the diffraction limit of optical data recording. It is shown that this limitation can at least in principle be overcome by the principle of spectral hole burning, which results in systems of storage capacities close to the human brain system.

Utilization of 5 MeV electron accelerator center and perspective

International Nuclear Information System (INIS)

Tanaka, Hiromi

1990-01-01

Electron beam process gives instantaneous effect as compared with heating process, and has such merits that energy consumption is very small, objects can be treated from outside, harmful chemicals are not used and treatment can be done as packed. The spread of electron beam process is largely due to the results of the development of highly reliable accelerators and utilization technologies, but as observed from all industrial fields, it is limited to only a part. In order to contribute to the solution of problems and the spread of electron beam process, Sumitomo Heavy Industries, Ltd. installed a 5 MeV, 200 kW large power accelerator developed by RDI in USA in the Electron Irradiation Application and Development Center opened in Tsukuba City. The Center was completed in June, 1989, and has carried out the activities of the development of irradiation utilization technologies, test irradiation and entrusted irradiation service. The features of electron beam process are high dose rate, the possibility of on and off as occasion demands, the preparation of radiation sources and the disposal of wastes being unnecessary, and no environmental problem. The industrialized processes, the types, energy and use of electron accelerators, the Tsukuba irradiation facilities and others are reported. (K.I.)

Hybridizing Differential Evolution with a Genetic Algorithm for Color Image Segmentation

Directory of Open Access Journals (Sweden)

R. V. V. Krishna

2016-10-01

Full Text Available This paper proposes a hybrid of differential evolution and genetic algorithms to solve the color image segmentation problem. Clustering based color image segmentation algorithms segment an image by clustering the features of color and texture, thereby obtaining accurate prototype cluster centers. In the proposed algorithm, the color features are obtained using the homogeneity model. A new texture feature named Power Law Descriptor (PLD which is a modification of Weber Local Descriptor (WLD is proposed and further used as a texture feature for clustering. Genetic algorithms are competent in handling binary variables, while differential evolution on the other hand is more efficient in handling real parameters. The obtained texture feature is binary in nature and the color feature is a real value, which suits very well the hybrid cluster center optimization problem in image segmentation. Thus in the proposed algorithm, the optimum texture feature centers are evolved using genetic algorithms, whereas the optimum color feature centers are evolved using differential evolution.

Advanced Plasmonic Materials for Dynamic Color Display.

Science.gov (United States)

Shao, Lei; Zhuo, Xiaolu; Wang, Jianfang

2018-04-01

Plasmonic structures exhibit promising applications in high-resolution and durable color generation. Research on advanced hybrid plasmonic materials that allow dynamically reconfigurable color control has developed rapidly in recent years. Some of these results may give rise to practically applicable reflective displays in living colors with high performance and low power consumption. They will attract broad interest from display markets, compared with static plasmonic color printing, for example, in applications such as digital signage, full-color electronic paper, and electronic device screens. In this progress report, the most promising recent examples of utilizing advanced plasmonic materials for the realization of dynamic color display are highlighted and put into perspective. The performances, advantages, and disadvantages of different technologies are discussed, with emphasis placed on both the potential and possible limitations of various hybrid materials for dynamic plasmonic color display. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Directional effect on coloration in LiF crystal by H{sup +} and H{sub 2}{sup +} ion bombardment

Energy Technology Data Exchange (ETDEWEB)

Mingle, Gan; Naramoto, Hiroshi; Aoki, Yasushi; Yamamoto, Shunya; Jianer, Zeng; Takeshita, Hidefumi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

1997-03-01

In the present paper, the first results are reported about the coloration in LiF crystals induced by bombardments of single hydrogen ions (H{sup +}) and molecular hydrogen ions (H{sub 2}{sup +}) with the same velocity under the <100> aligned and random conditions. For the single hydrogen ion irradiation, the coloration is rather simple. The F-type color center absorption under the <100> aligned condition becomes larger than that under the random condition with the dose increase because of larger fraction of electronic energy loss under channeling condition. On the contrary, the coloration for the molecular ions does not show big channeling effect. In the low dose region some difference can be seen but the difference of coloration is not observed any more with the dose increase. The pronounced coloration for molecular ions under the channeling condition is observed in comparison with that for single ions. (author)

Learning color receptive fields and color differential structure

NARCIS (Netherlands)

ter Haar Romenij, B.M.

2016-01-01

In this paper we study the role of brain plasticity, and investigate the emergence and self-emergence of receptive fields from scalar and color natural images by principal component analysis of image patches. We describe the classical experiment on localized PCA on center-surround weighted patches

Correlation between excited d-orbital electron lifetime in polaron dynamics and coloration of WO3 upon ultraviolet exposure

Science.gov (United States)

Lee, Young-Ahn; Han, Seung-Ik; Rhee, Hanju; Seo, Hyungtak

2018-05-01

Polarons have been suggested to explain the mechanism of the coloration of WO3 induced by UV light. However, despite the many experimental results that support small polarons as a key mechanism, direct observation of the carrier dynamics of polarons have yet to be reported. Here, we investigate the correlation between the electronic structure and the coloration of WO3 upon exposure to UV light in 5% H2/N2 gas and, more importantly, reveal photon-induced excited d-electron generation/relaxation via the W5+ oxidation state. The WO3 is fabricated by radio-frequency magnetron sputtering. X-ray diffraction patterns show that prepared WO3 is amorphous. Optical bandgap of 3.1 eV is measured by UV-vis before and after UV light. The results of Fourier transform infrared and Raman exhibit pristine WO3 is formed with surface H2O. The colored WO3 shows reduced state of W5+ state (34.3 eV) by using X-ray photoelectron spectroscopy. The valence band maximum of WO3 after UV light in H2 is shifted from mid gap to shallow donor by using ultraviolet photoelectron spectroscopy. During the exploration of the carrier dynamics, pump (700 nm)-probe (1000 nm) spectroscopy at the femtosecond scale was used. The results indicated that electron-phonon relaxation of UV-irradiated WO3, which is the origin of the polaron-induced local surface plasmonic effect, is dominant, resulting in slow decay (within a few picoseconds); in contrast, pristine WO3 shows fast decay (less than a picosecond). Accordingly, the long photoinduced carrier relaxation is ascribed to the prolonged hot-carrier lifetime in reduced oxides resulting in a greater number of free d-electrons and, therefore, more interactions with the W5+ sub-gap states.

Electron beam induced coloration and luminescence in layered structure of WO3 thin films grown by pulsed dc magnetron sputtering

International Nuclear Information System (INIS)

Karuppasamy, A.; Subrahmanyam, A.

2007-01-01

Tungsten oxide thin films have been deposited by pulsed dc magnetron sputtering of tungsten in argon and oxygen atmosphere. The as-deposited WO 3 film is amorphous, highly transparent, and shows a layered structure along the edges. In addition, the optical properties of the as-deposited film show a steplike behavior of extinction coefficient. However, the electron beam irradiation (3.0 keV) of the as-deposited films results in crystallization, coloration (deep blue), and luminescence (intense red emission). The above changes in physical properties are attributed to the extraction of oxygen atoms from the sample and the structural modifications induced by electron bombardment. The present method of coloration and luminescence has a potential for fabricating high-density optical data storage device

Electronically stimulated deep-center reactions in electron-irradiated InP: Comparison between experiment and recombination-enhancement theories

International Nuclear Information System (INIS)

Sibille, A.

1987-01-01

We present a detailed study of the recombination enhancement of several defect reactions involving the main deep centers in low-temperature electron-irradiated InP. A fairly good agreement is obtained with the Weeks-Tully-Kimerling theory for the activation energies of the enhanced process. On the other hand, a thorough investigation of a thermally and electronically stimulated defect transformation shows evidence that one major approximation (local vibrational equilibrium) fails, and that the recently proposed [H. Sumi, Phys. Rev. B 29, 4616 (1984)] mechanism of coherent recombination on deep centers is responsible for altered reaction rates at high injection levels

Multi-Center Electronic Structure Calculations for Plasma Equation of State

Energy Technology Data Exchange (ETDEWEB)

Wilson, B G; Johnson, D D; Alam, A

2010-12-14

We report on an approach for computing electronic structure utilizing solid-state multi-center scattering techniques, but generalized to finite temperatures to model plasmas. This approach has the advantage of handling mixtures at a fundamental level without the imposition of ad hoc continuum lowering models, and incorporates bonding and charge exchange, as well as multi-center effects in the calculation of the continuum density of states.

A new method for skin color enhancement

Science.gov (United States)

Zeng, Huanzhao; Luo, Ronnier

2012-01-01

Skin tone is the most important color category in memory colors. Reproducing it pleasingly is an important factor in photographic color reproduction. Moving skin colors toward their preferred skin color center improves the skin color preference on photographic color reproduction. Two key factors to successfully enhance skin colors are: a method to detect original skin colors effectively even if they are shifted far away from the regular skin color region, and a method to morph skin colors toward a preferred skin color region properly without introducing artifacts. A method for skin color enhancement presented by the authors in the same conference last year applies a static skin color model for skin color detection, which may miss to detect skin colors that are far away from regular skin tones. In this paper, a new method using the combination of face detection and statistical skin color modeling is proposed to effectively detect skin pixels and to enhance skin colors more effectively.

Color in present culture of European architecture

Science.gov (United States)

Schindler, Verena M.

2002-06-01

The influential architect Le Corbusier (1887 - 1965) was also involved in the adventure of contemporary painting, and color occupied half of his day, during twenty years, as he revealed in a study entitled 'Architectural Polychromy' written in the early thirties and recently published in 1997. In the present, contemporary architects in Central Europe are dealing with color in quite a different and exceptional way: most of them engage the artist to collaborate with them in their architectural projects. If painting is concerned with the interaction of color in the two-dimensional plane, architecture is deeply dependent on light and space, and deals entirely with the three- dimensional environment and its human perception. In the 1990s, the way architects and artists employed color in architecture was so striking that color offered a key to larger discussions and opened up an interesting aspect of architectural practice. It must be remembered that recent housing projects, such as the housing estate Pilotengasse in Vienna, Gigon & Guyer's Broelberg in Kilchberg (with Harald F. Muller), next to Zurich, and their Sport Center in Davos (with Adrian Schiess), Jean Nouvel's Cultural and Congress Center in Lucerne, or Sauerbruch & Hutton's Photonic Center and their GSW office building in Berlin have all been contributing to free color from its unconscious and dormant role. These works all impart qualities to color in architecture that were hitherto reserved to other materials and fields: they define the aspects of the interaction of visual and physical space, of materialization of volumes, and of the expression of wealth and luxury.

Geometric phase and quantum interference in photosynthetic reaction center: Regulation of electron transfer

Energy Technology Data Exchange (ETDEWEB)

Sun, Yuming, E-mail: ymsun@ytu.edu.cn; Su, Yuehua; Dai, Zhenhong; Wang, WeiTian

2016-10-20

Photosynthesis is driven by electron transfer in reaction centers in which the functional unit is composed of several simple molecules C{sub 2}-symmetrically arranged into two branches. In view of quantum mechanism, both branches are possible pathways traversed by the transferred electron. Due to different evolution of spin state along two pathways in transmembrane electric potential (TEP), quantum state of the transferred electron at the bridged site acquires a geometric phase difference dependent on TEP, the most efficient electron transport takes place in a specific range of TEP beyond which electron transfer is dramatically suppressed. What’s more, reaction center acts like elaborately designed quantum device preparing polarized spin dependent on TEP for the transferred electron to regulate the reduction potential at bridged site. In brief, electron transfer generates the TEP, reversely, TEP modulates the efficiency of electron transfer. This may be an important approach to maintaining an appreciable pH environment in photosynthesis.

2014 - Color & Infrared - Northeastern Vermont (0.5m)

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of natural color and color infrared digital ground orthoimagery covering a portion...

Multi-dimensional effects of color on the world wide web

Science.gov (United States)

Morton, Jill

2002-06-01

Color is the most powerful building material of visual imagery on the World Wide Web. It must function successfully as it has done historically in traditional two-dimensional media, as well as address new challenges presented by this electronic medium. The psychological, physiological, technical and aesthetic effects of color have been redefined by the unique requirements of the electronic transmission of text and images on the Web. Color simultaneously addresses each of these dimensions in this electronic medium.

Probing color-singlet exchange at D0

International Nuclear Information System (INIS)

Abbott, B.; Abolins, M.; Acharya, B.S.

1997-07-01

We present latest preliminary results on hard color-singlet exchange in proton-antiproton collisions. The fraction of dijet events produced via color-singlet exchange is measured as a function of jet transverse energy, dijet pseudorapidity separation, and proton-antiproton center-of-mass energy. These results are qualitatively consistent with a color-singlet fraction that increases with increasing quark-initiated processes

Spatial imaging in color and HDR: prometheus unchained

Science.gov (United States)

McCann, John J.

2013-03-01

The Human Vision and Electronic Imaging Conferences (HVEI) at the IS and T/SPIE Electronic Imaging meetings have brought together research in the fundamentals of both vision and digital technology. This conference has incorporated many color disciplines that have contributed to the theory and practice of today's imaging: color constancy, models of vision, digital output, high-dynamic-range imaging, and the understanding of perceptual mechanisms. Before digital imaging, silver halide color was a pixel-based mechanism. Color films are closely tied to colorimetry, the science of matching pixels in a black surround. The quanta catch of the sensitized silver salts determines the amount of colored dyes in the final print. The rapid expansion of digital imaging over the past 25 years has eliminated the limitations of using small local regions in forming images. Spatial interactions can now generate images more like vision. Since the 1950's, neurophysiology has shown that post-receptor neural processing is based on spatial interactions. These results reinforced the findings of 19th century experimental psychology. This paper reviews the role of HVEI in color, emphasizing the interaction of research on vision and the new algorithms and processes made possible by electronic imaging.

Positron-Electron Pairs in Astrophysics (Goddard Space Flight Center, 1983)

International Nuclear Information System (INIS)

Burns, M.L.; Harding, A.K.; Ramaty, R.

1983-01-01

A workshop on Position-Electron Pairs in Astrophysics was held in 1983 at the Goddard Space Flight Center. This workshop brought together observers and theorists actively engaged in the study of astrophysical sites, as well as physical processes therein where position-electron pairs have a profound influence on both the overall dynamics of the source region and the properties of the emitted radiation. This volume consists of the workshop proceedings

Tiny Devices Project Sharp, Colorful Images

Science.gov (United States)

2009-01-01

Displaytech Inc., based in Longmont, Colorado and recently acquired by Micron Technology Inc. of Boise, Idaho, first received a Small Business Innovation Research contract in 1993 from Johnson Space Center to develop tiny, electronic, color displays, called microdisplays. Displaytech has since sold over 20 million microdisplays and was ranked one of the fastest growing technology companies by Deloitte and Touche in 2005. Customers currently incorporate the microdisplays in tiny pico-projectors, which weigh only a few ounces and attach to media players, cell phones, and other devices. The projectors can convert a digital image from the typical postage stamp size into a bright, clear, four-foot projection. The company believes sales of this type of pico-projector may exceed $1.1 billion within 5 years.

Center for Molecular Electronics, University of Missouri, St. Louis. Environmental Assessment

Energy Technology Data Exchange (ETDEWEB)

1994-06-01

The Department of Energy (DOE) proposes to authorize the University of Missouri, St. Louis to proceed with the detailed design and construction of the proposed Center for Molecular Electronics. The proposed Center would consist of laboratories and offices housed in a three-story building on the University campus. The proposed modular laboratories would be adaptable for research activities principally related to physics, chemistry, and electrical engineering. Proposed research would include the development and application of thin-film materials, semi-conductors, electronic sensors and devices, and high-performance polymers. Specific research for the proposed Center has not yet been formulated, therefore, specific procedures for any particular process or study cannot be described at this time. The proposed construction site is an uncontaminated panel of land located on the University campus. This report contains information about the environmental assessment that was performed in accordance with this project.

User issues at the Stanford picosecond free electron laser center

International Nuclear Information System (INIS)

Smith, T.I.

1995-01-01

Assembling a productive user facility around a Free Electron Laser (FEL) is a complex task. Reliable operation of the FEL is a necessary, but by no means sufficient, condition to ensure that the center will be able to attract and keep the interest of first rate researchers. Some other issues which are important include: center wavelength stability and ease of tuning, bandwidth control, amplitude and position stability, ability to select arbitrary sequences of micropulses, and real time availability of information of the FEL's important parameters (spectral width, center wavelength, micropulse length and energy, etc.). In addition, at the Stanford Center we have found that providing additional systems (conventional picosecond lasers synchronized to the FEL, an FTIR spectrometer, a confocal microscopy, ...) has been important. (author)

Photoluminescence excitation spectroscopy of SiV- and GeV- color center in diamond

Science.gov (United States)

Häußler, Stefan; Thiering, Gergő; Dietrich, Andreas; Waasem, Niklas; Teraji, Tokuyuki; Isoya, Junichi; Iwasaki, Takayuki; Hatano, Mutsuko; Jelezko, Fedor; Gali, Adam; Kubanek, Alexander

2017-06-01

Color centers in diamond are important quantum emitters for a broad range of applications ranging from quantum sensing to quantum optics. Understanding the internal energy level structure is of fundamental importance for future applications. We experimentally investigate the level structure of an ensemble of few negatively charged silicon-vacancy (SiV-) and germanium-vacancy (GeV-) centers in bulk diamond at room temperature by photoluminescence (PL) and excitation (PLE) spectroscopy over a broad wavelength range from 460 to 650 {nm} and perform power-dependent saturation measurements. For SiV- our experimental results confirm the presence of a higher energy transition at ˜ 2.31 {eV}. By comparison with detailed theoretical simulations of the imaginary dielectric function we interpret the transition as a dipole-allowed transition from {}2{E}g-state to {}2{A}2u-state where the corresponding a 2u -level lies deeply inside the diamond valence band. Therefore, the transition is broadened by the diamond band. At higher excitation power of 10 {mW} we indicate signs of a parity-conserving transition at ˜ 2.03 {eV} supported by saturation measurements. For GeV- we demonstrate that the PLE spectrum is in good agreement with the mirror image of the PL spectrum of the zero-phonon line. Experimentally we do not observe a higher lying energy level up to a transition wavelength of 460 {nm}. The observed PL spectra are identical, independent of excitation wavelength, suggesting a rapid decay to {}2{E}u excited state and followed by optical transition to {}2{E}g ground state. Our investigations convey important insights for future quantum optics and quantum sensing experiments based on SiV--center and GeV--center in diamond.

Two-electron germanium centers with a negative correlation energy in lead chalcogenides

International Nuclear Information System (INIS)

Terukov, E. I.; Marchenko, A. V.; Zaitseva, A. V.; Seregin, P. P.

2007-01-01

It is shown that the charge state of the 73 Ge antisite defect that arises in anionic sublattices of PbS, PbSe, and PbTe after radioactive transformation of 73 As does not depend on the position of the Fermi level, whereas the 73 Ge center in cationic sublattices of PbS and PbSe represents a two-electron donor with the negative correlation energy: the Moessbauer spectrum for the n-type samples corresponds to the neutral state of the donor center (Ge 2+ ), while this spectrum corresponds to the doubly ionized state (Ge 4+ ) of the center in the p-type samples. In partially compensated PbSe samples, a fast electron exchange between the neutral and ionized donor centers is realized. It is shown by the method of Moessbauer spectroscopy for the 119 Sn isotope that the germanium-related energy levels are located higher than the levels formed in the band gap of these semiconductors by the impurity tin atoms

Formation and properties of metallic nanoparticles in lithium and sodium fluorides with radiation-induced color centers

Science.gov (United States)

Bryukvina, L. I.; Martynovich, E. F.

2012-12-01

The specific features of light- and temperature-induced formation of metallic nanoparticles in γ-irradiated LiF and NaF crystals have been investigated. Atomic force microscope images of nanoparticles of different sizes and in different locations have been presented. The relation between the crystal processing regimes and properties of the nanoparticles formed has been revealed. The optical properties of the processed crystals have been analyzed. The thermo- and light-stimulated processes underlying the formation of metallic nanoparticles in aggregation of the color centers and their decay due to the recovery of the crystal lattice have been studied.

Confocal fluorescence microscopy investigation of visible emitting defects induced by electron beam lithography in LIF films

Energy Technology Data Exchange (ETDEWEB)

Montereali, R.M.; Bigotta, S.; Pace, A.; Piccinini, M. [ENEA, Divisione Fisica Applicata, Centro Ricerche Frascati, Frascati, RM (Italy); Burattini, E.; Grilli, A.; Raco, A. [Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Fisica, Frascati, Rome (Italy); Giammatteo, M. [Unita' Istituto Nazionale di Fisica Nucleare, Frascati, RM (Italy)]|[L' Aquila Univ., L' Aquila (Italy). Centro di Microscopia Elettronica; Picozzi, P.; Santucci, S. [Unita' Istituto Nazionale di Fisica Nucleare, Frascati, RM (Italy)]|[L' Aquila Univ., L' Aquila (Italy). Dipt. di Fisica

2000-07-01

Low energy electron irradiation of lithium fluoride (LiF), in the form of bulk crystals and films, gives rise to the stable formation of primary F defects and aggregated color centers in a thin layer located at the surface of the investigated material. For the first time a confocal light scanning microscope (CLSM) in fluorescence mode was used to reconstruct the depth distribution of efficiently emitting laser active color centers in a stripe-like region induced by 12 and 16 keV electrons on LiF films thermally evaporated on glass. The formation of the F{sub 3}{sup +} and F{sub 2} aggregated defects appears restricted to the electron penetration and proportional to their energy depth profile, as obtained from Monte Carlo simulations. [Italian] L'irraggiamento con elettroni di bassa energia del fluoruro di litio (LiF), in forma di cristalli e film, induce la formazione di difetti primari F e centri di colore aggregati stabili in un sottile strato localizzato alla superficie del materiale investigato. Per la prima volta un microscopio confocale a scansione (CLSM) in modalita' fluorescenza e' stato usato per ricostruire la distribuzione di centri di colore laser attivi ad alta efficienza di emissione nel visibile, in strisce colorate ottenute con elettroni da 12 e 16 keV su film di LiF evaporati termicamente su vetro. La formazione dei difetti aggregati F2 e F3+ risulta ristretta spazialmente nella regione di penetrazione degli elettroni e proporzionale al profilo della distribuzione dell'energia da essi depositata, ricavata tramite simulazioni Monte Carlo.

Towards representation of a perceptual color manifold using associative memory for color constancy.

Science.gov (United States)

Seow, Ming-Jung; Asari, Vijayan K

2009-01-01

In this paper, we propose the concept of a manifold of color perception through empirical observation that the center-surround properties of images in a perceptually similar environment define a manifold in the high dimensional space. Such a manifold representation can be learned using a novel recurrent neural network based learning algorithm. Unlike the conventional recurrent neural network model in which the memory is stored in an attractive fixed point at discrete locations in the state space, the dynamics of the proposed learning algorithm represent memory as a nonlinear line of attraction. The region of convergence around the nonlinear line is defined by the statistical characteristics of the training data. This learned manifold can then be used as a basis for color correction of the images having different color perception to the learned color perception. Experimental results show that the proposed recurrent neural network learning algorithm is capable of color balance the lighting variations in images captured in different environments successfully.

Enforced Electrical Neutrality of the Color-Flavor Locked Phase

International Nuclear Information System (INIS)

Rajagopal, Krishna; Wilczek, Frank

2001-01-01

We demonstrate that quark matter in the color-flavor locked phase of QCD is rigorously electrically neutral, despite the unequal quark masses, and even in the presence of an electron chemical potential. As long as the strange quark mass and the electron chemical potential do not preclude the color-flavor locked phase, quark matter is automatically neutral. No electrons are required and none are admitted

Electron exchange between neutral and ionized impurity iron centers in vitreous arsenic selenide

Energy Technology Data Exchange (ETDEWEB)

Marchenko, A. V. [Herzen State Pedagogical University of Russia (Russian Federation); Terukov, E. I. [Russian Academy of Sciences, Ioffe Physical–Technical Institute (Russian Federation); Egorova, A. Yu. [St.-Petersburg Mining University (Russian Federation); Kiselev, V. S.; Seregin, P. P., E-mail: ppseregin@mail.ru [Herzen State Pedagogical University of Russia (Russian Federation)

2017-04-15

Impurity iron atoms in vitreous arsenic-selenide As{sub 2}Se{sub 3} films modified by iron form one-electron donor centers with an ionization energy of 0.24 (3) eV (the energy is counted from the conduction-band bottom). The Fermi level is shifted with an increase in the iron concentration from the mid-gap to the donorlevel position of iron due to the filling of one-electron states of the acceptor type lying below the Fermi level. At an iron concentration of ≥3 at %, the electron-exchange process is observed between neutral and ionized iron centers resulting in a change both in the electron density and in the tensor of the electric-field gradient at iron-atom nuclei with increasing temperature above 350 K.

2016 - Color & Infrared - Rutland and Windsor (0.15m)

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of natural color and color infrared digital ground orthoimagery covering a portion...

2016 - Color & Infrared - Rutland and Windsor (0.3m)

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of natural color and color infrared digital ground orthoimagery covering a portion...

FNTD radiation dosimetry system enhanced with dual-color wide-field imaging

International Nuclear Information System (INIS)

Akselrod, M.S.; Fomenko, V.V.; Bartz, J.A.; Ding, F.

2014-01-01

At high neutron and photon doses Fluorescent Nuclear Track Detectors (FNTDs) require operation in analog mode and the measurement results depend on individual crystal color center concentration (coloration). We describe a new method for radiation dosimetry using FNTDs, which includes non-destructive, automatic sensitivity calibration for each individual FNTD. In the method presented, confocal laser scanning fluorescent imaging of FNTDs is combined with dual-color wide field imaging of the FNTD. The calibration is achieved by measuring the color center concentration in the detector through fluorescence imaging and reducing the effect of diffuse reflection on the lapped surface of the FNTD by imaging with infra-red (IR) light. The dual-color imaging of FNTDs is shown to provide a good estimation of the detector sensitivity at high doses of photons and neutrons, where conventional track counting is impeded by track overlap. - Highlights: • New method and optical imaging head was developed for FNTD used at high doses. • Dual-color wide-field imaging used for color center concentration measurement. • Green fluorescence corrected by diffuse reflection used for sensitivity correction. • FNTD dose measurements performed in analog processing mode

Improving patient-centered communication while using an electronic health record: Report from a curriculum evaluation.

Science.gov (United States)

Fogarty, Colleen T; Winters, Paul; Farah, Subrina

2016-05-01

Researchers and clinicians are concerned about the impact of electronic health record use and patient-centered communication. Training about patient-centered clinical communication skills with the electronic health record may help clinicians adapt and remain patient-centered. We developed an interactive workshop eliciting challenges and opportunities of working with the electronic health record in clinical practice, introduction of specific patient-centered behaviors and mindful practice techniques, and video demonstrating contrasts in common behavior and "better practices." One hundred thirty-nine resident physicians and faculty supervisors in five residency training programs at the University of Rochester Medical Center participated in the workshops. Participants were asked to complete an 11-item survey of behaviors related to their use of the electronic health record prior to training and after attending training. We used paired t-tests to assess changes in self-reported behavior from pre-intervention to post-intervention. We trained 139 clinicians in the workshops; 110 participants completed the baseline assessment and 39 completed both the baseline and post-intervention assessment. Data from post-curriculum respondents found a statistically significant increase in "I told the patient when turning my attention from the patient to the computer," from 60% of the time prior to the training to 70% of the time after. Data from our program evaluation demonstrated improvement in one communication behavior. Sample size limited the detection of other changes; further research should investigate effective training techniques for patient-centered communication while using the electronic health record. © The Author(s) 2016.

Luminescence of color centers in MgF{sub 2} crystals; Lyuminestsentsiya tsentrov okraski v kristallakh MgF{sub 2}

Energy Technology Data Exchange (ETDEWEB)

Vakhidov, Sh A; Nuritdinov, I; Musaeva, M A [Inst. Yadernoj Fizili AN Uzbekistana, Tashkent (Uzbekistan)

1999-08-01

The photoluminescence characteristics of the proper radiation color centers of the MgF{sub 2} crystals are studied. The samples were irradiated by the {sup 60}Co source {gamma}-rays up to the dose 10{sup 7}Gy. The bands with the maxima in the area of 420, 460, 550 and 620 nm were identified, which are excited correspondingly in the bands with the maxima of 370, 320, 410 and 480 nm.

Tricolore. A flexible color scale for ternary compositions

DEFF Research Database (Denmark)

2018-01-01

tricolore is an R library providing a flexible color scale for the visualization of three-part/ternary compositions. Its main functionality is to color-code any ternary composition as a mixture of three primary colours and to draw a suitable color-key. tricolore flexibly adapts to different...... visualisation challenges via - discrete and continuous color support - support for unbalanced compositional data via centering - support for data with very narrow range via scaling - hue, chroma and lightness options...

Piezoelectric energy harvesting from colored fat-tailed fluctuations: An electronic analogy

Directory of Open Access Journals (Sweden)

J. I. Peña Rosselló

2015-09-01

Full Text Available Aiming to optimize piezoelectric energy harvesting from strongly col-ored fat-tailed fluctuations, we have recently studied the performance ofa monostable inertial device under a noise whose statistics depends on aparameter q (bounded for q 1.We have studied the interplay between the potential shape (interpolatingbetween square-well and harmonic-like behaviors and the noise’s statis-tics and spectrum, and showed that its output power grows as q increasesabove 1. We now report a real experiment on an electronic analog of theproposed system, which sheds light on its operating principle. Received: 20 Novembre 2014, Accepted: 7 September 2015; Edited by: C. A. Condat, G. J. Sibona; DOI:http://dx.doi.org/10.4279/PIP.070014 Cite as: J I Peña Rosselló, R Deza, J . Deza, H S Wio, Papers in Physics 7, 070014 (2015

Primary and aggregate color centers in proton irradiated LiF crystals and thin films for luminescent solid state detectors

Science.gov (United States)

Piccinini, M.; Ambrosini, F.; Ampollini, A.; Bonfigli, F.; Libera, S.; Picardi, L.; Ronsivalle, C.; Vincenti, M. A.; Montereali, R. M.

2015-04-01

Proton beams of 3 MeV energy, produced by the injector of a linear accelerator for proton therapy, were used to irradiate at room temperature lithium fluoride crystals and polycrystalline thin films grown by thermal evaporation. The irradiation fluence range was 1011-1015 protons/cm2. The proton irradiation induced the stable formation of primary and aggregate color centers. Their formation was investigated by optical absorption and photoluminescence spectroscopy. The F2 and F3+ photoluminescence intensities, carefully measured in LiF crystals and thin films, show linear behaviours up to different maximum values of the irradiation fluence, after which a quenching is observed, depending on the nature of the samples (crystals and films). The Principal Component Analysis, applied to the absorption spectra of colored crystals, allowed to clearly identify the formation of more complex aggregate defects in samples irradiated at highest fluences.

Care team identification in the electronic health record: A critical first step for patient-centered communication.

Science.gov (United States)

Dalal, Anuj K; Schnipper, Jeffrey L

2016-05-01

Patient-centered communication is essential to coordinate care and safely progress patients from admission through discharge. Hospitals struggle with improving the complex and increasingly electronic conversation patterns among care team members, patients, and caregivers to achieve effective patient-centered communication across settings. Accurate and reliable identification of all care team members is a precursor to effective patient-centered communication and ideally should be facilitated by the electronic health record. However, the process of identifying care team members is challenging, and team lists in the electronic health record are typically neither accurate nor reliable. Based on the literature and on experience from 2 initiatives at our institution, we outline strategies to improve care team identification in the electronic health record and discuss potential implications for patient-centered communication. Journal of Hospital Medicine 2016;11:381-385. © 2016 Society of Hospital Medicine. © 2016 Society of Hospital Medicine.

Electrolytic coloration of O22--doped NaCl crystals

International Nuclear Information System (INIS)

Qin Fang; Gu Hongen; Song Cuiying; Wang Na; Guo Meili; Wang Fen; Liu Jia

2007-01-01

O 2 2- -doped NaCl crystals are colored electrolytically by using a pointed cathode and a flat anode at various temperatures and voltages, which mainly benefit from appropriate coloration temperatures and voltages as well as anode structure of used electrolysis apparatus. Characteristic OH - , U, V 2 m , U A , V 2 , V 3 , O 2- -V a + complex, F, R 1 , R 2 and M absorption bands are observed in absorption spectra of the colored crystals. Production and conversion of color centers in electrolytic coloration is explained. Current-time curves for electrolytic colorations and their relationships with electrolytic colorations were given

The reasons for the color green fluorite Mehmandooye cover using UV spectroscopy and XRF results

Science.gov (United States)

Pirzadeh, Sara; Zahiri, Reza

2016-04-01

Fluorite mineral or fluorine with chemical formula CaF2 is most important mineralfluor in nature. This mineral crystallization to colors yellow, green, pink, blue, purple, colorless and sometimes black andin cubic system crystallized.assemi transparent and glass with polished.fluoritethe purity include 48/9% fluoreand 51/9% calcium. How the creation colors in minerals different greatly indebted to Kurt Nassau research from Bell Labs, Murray Hill, New Jersey.almostall the mechanisms that cause color in minerals, are the result of the interaction of light waves with the electrons The main factors affecting the color generation include the following: 1)the presence of a constructive element inherent (essential ingredient mineral composition) 2)The presence of a minor impurities (such a element as involved in latticesolid solution) 3) appearancedefects in the crystal structure 4) There are some physical boundaries with distances very small and delicate, like blades out of the solution (which may be the play of colors or Chatvyansy) 5) Mixing mechanical impurities dispersed in a host mineral Based on the results of the analysis, XRF and UV spectrum and also based on the results of ICP, because the color green fluorite examined, the focus color (F_center) and also the presence of some elementsintermediate (such as Y (yttrium). [1] Bill, H., Calas, G. Color centres associated rare earth ions and the origin of coloration in natural fluorites// PhysChem Min, (1978), v 3, pp. 117-131.

Design and Synthesis of a Coumarin-based Acidichromic Colorant

Directory of Open Access Journals (Sweden)

Ding-Yah Yang

2007-07-01

Full Text Available This paper describes the fine-tuning of the acidichromic properties of a coumarin-containing colorant 1 by incorporation of electron-donating and electron-withdrawing substituents on the coumarin moiety. Colorant 1 can undergo two distinct and reversible color changes under both strongly acidic and basic conditions, but not in the presence of gaseous ammonia. The results indicated that the bromo-substituted compound 5b changes from red to yellow when exposed to gaseous ammonia, both in solution and on polycarbonate film, suggesting that an electron-withdrawing group at the 7-position of the coumarin moiety made the enolic hydrogen on 5b more susceptible to deprotonation by a base than in the unsubstituted compound 1.

Electron Microscopist | Center for Cancer Research

Science.gov (United States)

PROGRAM DESCRIPTION The Cancer Research Technology Program (CRTP) develops and implements emerging technology, cancer biology expertise and research capabilities to accomplish NCI research objectives. The CRTP is an outward-facing, multi-disciplinary hub purposed to enable the external cancer research community and provides dedicated support to NCI’s intramural Center for Cancer Research (CCR). The dedicated units provide electron microscopy, protein characterization, protein expression, optical microscopy and genetics. These research efforts are an integral part of CCR at the Frederick National Laboratory for Cancer Research (FNLCR). CRTP scientists also work collaboratively with intramural NCI investigators to provide research technologies and expertise. KEY ROLES/RESPONSIBILITIES - THIS POSITION IS CONTINGENT UPON FUNDING APPROVAL The Electron Microscopist will: Operate ultramicrotomes (Leica) and other instrumentation related to the preparation of embedded samples for EM (TEM and SEM) Operate TEM microscopes, (specifically Hitachi, FEI T20 and FEI T12) as well as SEM microscopes (Hitachi); task will include loading samples, screening, and performing data collection for a variety of samples: from cells to proteins Manage maintenance for the TEM and SEM microscopes Provide technical advice to investigators on sample preparation and data collection

Ferrocene-Functionalized Graphene Oxide Nanosheets: Efficient Electronic Communication between Ferrocene Centers across Graphene Nanosheets

International Nuclear Information System (INIS)

Lu, Yizhong; Jiang, Yuanyuan; Wu, Haibin; Chen, Wei

2015-01-01

Highlights: • Graphene oxide (GO) nanosheets functionalized with ferrocenyl moieties (GO-Fc) are fabricated. • GO-Fc shows efficient electronic communication between ferrocene centers. • GO-Fc exhibits two pairs of voltammetric peaks with a large potential spacing of 0.515 V. • GO-Fc shows a broad absorption peak in the near-infrared range (∼ 1428 nm) at mixed valence. - Abstract: Graphene oxide (GO) nanosheets functionalized with ferrocenyl moieties (GO-Fc) were fabricated through strong covalent C−C bonds. The resulting hybrid showed efficient electronic communication between ferrocene centers due to the strong electron delocalization facilitated by the large pi-pi conjugated structure of graphene sheets. The obtained hybrid exhibited two pairs of voltammetric peaks with a large potential spacing of 0.515 V and a broad absorption peak in the near-infrared range (∼ 1428 nm) at mixed valence. The electrochemical and near IR spectroscopic features suggested a Class II/III behavior of the intervalence charge transfer. This work indicates clearly that strong electronic coupling between ferrocene centers can be easily realized across graphene nanosheets with sp 2 -hybridized carbon

Structural, morphological and optical investigations on electron-beam irradiated PbF2-TeO2-B2O3-Eu2O3 glasses

Science.gov (United States)

Wagh, Akshatha; Petwal, Vikash; Dwivedi, Jishnu; Upadhyaya, V.; Raviprakash, Y.; Kamath, Sudha D.

2016-09-01

Combined structural, optical and morphological studies were carried out on Eu2O3 doped PbF2-TeO2-B2O3 glass samples, before and after being subjected to electron beam of energy 7.5 MeV. XRD confirmed the amorphous nature of the glasses even after 150 kGy electron beam irradiation. Densities of the irradiated samples showed slightly greater values when compared to their respective values before irradiation, which proved the increase in the compaction of the network. The intensities of the three prominent bands; B-O-B linkages, BO4 units and BO3 units of FT-IR spectra, of the titled glasses, showed slight decrease after electron beam irradiation. The decrement in the values of energy band gap and shift in cut-off wavelength towards red edge, proved the formation of color centers in the glass network after irradiation. The change in Hunter L values, through color measurement was a proof for the Farbe/color/absorption centers created in the glass sites after irradiation.

Primary and aggregate color centers in proton irradiated LiF crystals and thin films for luminescent solid state detectors

International Nuclear Information System (INIS)

Piccinini, M; Ambrosini, F; Ampollini, A; Bonfigli, F; Libera, S; Picardi, L; Ronsivalle, C; Vincenti, M A; Montereali, R M

2015-01-01

Proton beams of 3 MeV energy, produced by the injector of a linear accelerator for proton therapy, were used to irradiate at room temperature lithium fluoride crystals and polycrystalline thin films grown by thermal evaporation. The irradiation fluence range was 10 11 -10 15 protons/cm 2 . The proton irradiation induced the stable formation of primary and aggregate color centers. Their formation was investigated by optical absorption and photoluminescence spectroscopy. The F 2 and F 3 + photoluminescence intensities, carefully measured in LiF crystals and thin films, show linear behaviours up to different maximum values of the irradiation fluence, after which a quenching is observed, depending on the nature of the samples (crystals and films). The Principal Component Analysis, applied to the absorption spectra of colored crystals, allowed to clearly identify the formation of more complex aggregate defects in samples irradiated at highest fluences. (paper)

Color coherence in W + jet events

International Nuclear Information System (INIS)

Abbott, B.

1997-11-01

We report on preliminary studies of color coherence effects in p anti p collisions, based on data collected by the D0 detector during the 1994-1995 run of the Fermilab Tevatron collider, at a center of mass energy √s = 1.8 TeV. Color interference effects are studied by examining particle distribution patterns in W + Jet events. The data are compared to Monte Carlo simulations with different color coherence implementations and to a recent analytic Modified-Leading-Log perturbative calculation based on the Local Parton-Hadron Duality hypothesis. Soft particle radiation is enhanced in the event plane relative to the transverse plane, in agreement with calculations in which the effects of color coherence are fully included

Plate Full of Color

Centers for Disease Control (CDC) Podcasts

2008-08-04

The Eagle Books are a series of four books that are brought to life by wise animal characters - Mr. Eagle, Miss Rabbit, and Coyote - who engage Rain That Dances and his young friends in the joy of physical activity, eating healthy foods, and learning from their elders about health and diabetes prevention. Plate Full of Color teaches the value of eating a variety of colorful and healthy foods.  Created: 8/4/2008 by National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP).   Date Released: 8/5/2008.

N-V related fluorescence of the monoenergetic high energy electron irradiated diamond nanoparticles

Czech Academy of Sciences Publication Activity Database

Remeš, Zdeněk; Mičová, Júlia; Krist, Pavel; Chvátil, David; Effenberg, R.; Nesladek, M.

2015-01-01

Roč. 212, č. 11 (2015), s. 2519-2524 ISSN 1862-6300 R&D Projects: GA ČR(CZ) GA14-05053S Institutional support: RVO:68378271 ; RVO:61389005 Keywords : nanodiamonds * photoluminescence * microtron * electron accelerator * color center Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 1.648, year: 2015

Possible influences on color constancy by motion of color targets and by attention-controlled gaze.

Science.gov (United States)

Wan, Lifang; Shinomori, Keizo

2018-04-01

We investigated the influence of motion on color constancy using a chromatic stimulus presented in various conditions (static, motion, and rotation). Attention to the stimulus and background was also controlled in different gaze modes, constant fixation of the stimulus, and random viewing of the stimulus. Color constancy was examined in six young observers using a haploscopic view of a computer monitor. The target and background were illuminated in simulation by red, green, blue, and yellow, shifted from daylight (D65) by specific color differences along L - M or S - (L + M) axes on the equiluminance plane. The standard pattern (under D65) and test pattern (under the color illuminant) of a 5-deg square were presented side by side, consisting of 1.2-deg square targets with one of 12 colors at each center, surrounded by 230 background ellipses consisting of eight other colors. The central color targets in both patterns flipped between top and bottom locations at the rate of 3 deg/s in the motion condition. The results indicated an average reduction of color constancy over the 12 test colors by motion. The random viewing parameter indicated better color constancy by more attention to the background, although the difference was not significant. Color constancy of the four color illuminations was better to worse in green, red, yellow, and blue, respectively. The reduction of color constancy by motion could be explained by less contribution of the illumination estimation effect on color constancy. In the motion with constant fixation condition, the retina strongly adapted to the mean chromaticity of the background. However, motion resulted in less attention to the color of the background, causing a weaker effect of the illumination estimation. Conversely, in the static state with a random viewing condition, more attention to the background colors caused a stronger illumination estimation effect, and color constancy was improved overall.

The influence of electron energy on accumulation of color centers in reflective coatings based on ZnO

International Nuclear Information System (INIS)

Mikhajlov, M.M.; Sharafutdinova, V.V.

1998-01-01

The effect of the electron energy on the change of the intensity of bands of proper point defects of zinc oxides and thermo-regulating coatings on its basis for space vehicles is investigated in the range 10-100 keV. It is found that the growth of the intensity up to the energy ∼ 15 keV and then its decreasing is observed in the range 10-100 keV. The explanation of this singularity is proposed. It is found that the concentration of free electrons with the growth of the accelerated electron energy increases according to the exponential law

Color Gradient in the King Type Globular Cluster NGC 7089

Directory of Open Access Journals (Sweden)

Young-Jong Sohn

1999-12-01

Full Text Available We use BV CCD images to investigate the reality of the color gradient within a King type globular cluster NGC 7089. Surface photometry shows that there is a strong radial color gradient in the central region of the cluster in the sense of bluer center with the amplitude of -0.39 +/- 0.07 mag/arcsec2 in (B - V. In the outer region of the cluster, however, the radial color gradient shows a reverse case, i.e., redder toward the center. (B - V color profile which was derived from resolved stars in VGC 7089 field also shows a significant color gradient in the central region of the clusters, indicating that lights from the combination of red giant stars and blue horizontal branch stars cause the radial color gradient. Color gradient of the outer region of NGC 7089 may be due to the unresolved background of the cluster. Similar color gradients in the central area of clusters have been previously observed exserved exclusively in highly concentrated systems classified as post core collapse clusters. We caution, however, to confirm the reality of the color gradient from resolved stars, we need more accurate imaging data of the cluster with exceptional seeing condition because the effect of completeness correlates with local density of stars.

Investigation of electron exchange between neutral and ionized centers of germanium in PbSe

International Nuclear Information System (INIS)

Terukov, I.E.; Khuzhakulov, Eh.S.

2005-01-01

The 73 As( 73 Ge) emission Moessbauer spectroscopy is applied to study the electron exchange between neutral ionized states of the germanium donor center in PbSe. It is shown that the charge state of the antistructural 73 Ge defect, generating in the anion PbSe sublattice after 73 As radioactive decay, does not depend on the Fermi level location. In contrast to this, the 73 Ge center in the cation PbSe sublattice is the isoelectronic substitution impurity. The analysis of emission Moessbauer spectra of p-type PbSe: 73 As testifies about the presence of the fast electron exchange between neutral and ionized donor Ge centers in PbSe [ru

Distinction between amorphous and healed planar deformation features in shocked quartz using composite color scanning electron microscope cathodoluminescence (SEM-CL) imaging

Science.gov (United States)

Hamers, Maartje F.; Pennock, Gill M.; Herwegh, Marco; Drury, Martyn R.

2016-10-01

Planar deformation features (PDFs) in quartz are one of the most reliable and most widely used forms of evidence for hypervelocity impact. PDFs can be identified in scanning electron microscope cathodoluminescence (SEM-CL) images, but not all PDFs show the same CL behavior: there are nonluminescent and red luminescent PDFs. This study aims to explain the origin of the different CL emissions in PDFs. Focused ion beam (FIB) thin foils were prepared of specific sample locations selected in composite color SEM-CL images and were analyzed in a transmission electron microscope (TEM). The FIB preparation technique allowed a direct, often one-to-one correlation between the CL images and the defect structure observed in TEM. This correlation shows that composite color SEM-CL imaging allows distinction between amorphous PDFs on one hand and healed PDFs and basal Brazil twins on the other: nonluminescent PDFs are amorphous, while healed PDFs and basal Brazil twins are red luminescent, with a dominant emission peak at 650 nm. We suggest that the red luminescence is the result of preferential beam damage along dislocations, fluid inclusions, and twin boundaries. Furthermore, a high-pressure phase (possibly stishovite) in PDFs can be detected in color SEM-CL images by its blue luminescence.

Color ornaments and territory position in king penguins.

Science.gov (United States)

Keddar, Ismaël; Jouventin, Pierre; Dobson, F Stephen

2015-10-01

King penguins exhibit mutual color ornamentation of feathers and beak color. They breed in dense colonies and produce a single chick every 2 years. Thus, males and females must choose partners carefully to be reproductively successful, and auricular patches of males and UV coloration of beak spots have been shown to influence mate choice. Position in the breeding colony is also important to reproductive success, with pairs on the edge of the colony less successful than those in the center. We studied the mutual ornaments, individual condition, and position of pairs in their breeding colony. Males were significantly larger than females in size, body mass, and auricular patch size. Within pairs, auricular patch size of males and females were significantly correlated, and male auricular patch size and body mass were significantly associated, suggesting a link between this ornament and male body condition. Moving from the edge to the center of the colony, pairs had larger yellow-orange auricular patches, indicating a link between this ornament and settlement in higher quality territories in the center of the colony. Pairs were also less brightly brown colored on the breast and less saturated in UV color of the beak spot. Since we observed pairs that were settling for egg laying, location in the colony may have reflected aspects of pair condition, rather than later jockeying for positioning using ornaments as signals of behavioral dominance. Copyright © 2015 Elsevier B.V. All rights reserved.

Repairing method of color TV with measuring instrument

International Nuclear Information System (INIS)

1996-01-01

This book concentrates on repairing method of color TV with measuring instrument, which deals with direction and sorts of measuring instrument for service, application and basic technique of an oscilloscope and a synchroscope, constituent of TV and wave reading, everything for test skill for service man, service technique by electronic voltmeter, service technique by sweep generator and maker generator, dot-bar generator and support skill for color TV and color bar generator and application technology of color circuit.

Recombination luminescence from H centers and conversion of H centers into I centers in alkali iodides

International Nuclear Information System (INIS)

Berzina, B.J.

1981-01-01

The study is aimed at the search for H-plus-electron centers of luminescence and the investigation of the conversion of H- into I centers by the luminescence of H-plus-electron centers in alkali iodide crystals. KI, RbI and NaI crystals were studied at 12 K. H and F centers were created by irradiation with ultraviolet light corresponding to the absorption band of anion excitons. Then the excitation of electron centers by red light irradiation was followed. The spectra of stimulated recombination luminescence were studied. The luminescence of H-plus- electron centers had been observed and the conclusion was made that this center was formed on immobile H centers. In case of stable H centers the optically stimulated conversion of H centers into I centers occurs. The assumption is advanced on the spontaneous annihilation of near placed unstable F, H centers which leads to the creation of H-plus-electron luminescence centers and to the spontaneous H-I-centers conversion [ru

Subwavelength Plasmonic Color Printing Protected for Ambient Use

DEFF Research Database (Denmark)

Roberts, Alexander Sylvester; Pors, Anders Lambertus; Albrektsen, Ole

2014-01-01

We demonstrate plasmonic color printing with subwavelength resolution using circular gap-plasmon resonators (GPRs) arranged in 340 nm period arrays of square unit cells and fabricated with single-step electron-beam lithography. We develop a printing procedure resulting in correct single-pixel color...... reproduction, high color uniformity of colored areas, and high reproduction fidelity. Furthermore, we demonstrate that, due to inherent stability of GPRs with respect to surfactants, the fabricated color print can be protected with a transparent dielectric overlay for ambient use without destroying its...... coloring. Using finite-element simulations, we uncover the physical mechanisms responsible for color printing with GPR arrays and suggest the appropriate design procedure minimizing the influence of the protection layer....

Calculation of two-center one-electron molecular integrals with STOs

International Nuclear Information System (INIS)

Rico, J.F.; Lopez, R.; Paniagua, M.; Ramirez, G.

1991-01-01

A program for the calculation of two-center one-electron integrals (overlap, nuclear attraction and kinetic energy) between real Slater-type orbitals (STOs) is reported. The integrals are obtained by recursion over simple auxiliary matrices, whose elements are calculated in terms of further auxiliary functions evaluated in a quick and accurate way. (orig.)

The color of polarization in cuprate superconductors

International Nuclear Information System (INIS)

Hoff, H.A.; Osofsky, M.S.; Lechter, W.L.; Pande, C.S.

1991-01-01

A technique for the identification of individual anisotropic grains in a heterogeneous and opaque material involves the observation of grain color in reflected light through crossed polarizers (color of polarization). Such colors are generally characteristic of particular phases. When grains of many members of the class of hole carrier cuprate superconductors are so viewed at room temperature with a 'daylight' source, a characteristic color of polarization is observed. This color was studied in many of these cuprate superconductors and a strong correlation was found between color and the existence of superconductivity. Two members were also examined of the electron cuprate superconductors and it was found that they possess the same color of polarization as the hole carrier cuprate superconductors so far examined. The commonality of the characteristic color regardless of charge carrier indicates that the presence of this color is independent of carrier type. The correlation of this color with the existence of superconductivity in the cuprate superconductors suggests that the origin of the color relates to the origin of superconductivity. Photometric techniques are also discussed

Gapless Color-Flavor-Locked Quark Matter

DEFF Research Database (Denmark)

Alford, Mark; Kouvaris, Christoforos; Rajagopal, Krishna

2004-01-01

In neutral cold quark matter that is sufficiently dense that the strange quark mass M_s is unimportant, all nine quarks (three colors; three flavors) pair in a color-flavor locked (CFL) pattern, and all fermionic quasiparticles have a gap. We argue that as a function of decreasing quark chemical...... potential mu or increasing M_s, there is a quantum phase transition from the CFL phase to a new ``gapless CFL phase'' in which only seven quasiparticles have a gap. The transition occurs where M_s^2/mu is approximately equal to 2*Delta, with Delta the gap parameter. Gapless CFL, like CFL, leaves unbroken...... a linear combination Qtilde of electric and color charges, but it is a Qtilde-conductor with a nonzero electron density. These electrons and the gapless quark quasiparticles make the low energy effective theory of the gapless CFL phase and, consequently, its astrophysical properties are qualitatively...

Electronic relaxations of radiative defects of the anion sublattice in cesium bromide crystals and exoemission of electrons

CERN Document Server

Galyij, P V

2002-01-01

The paper presents the results of investigations of thermostimulated exoelectron emission (TSEE) from CsBr crystal, excited by moderate doses (D <= 10 sup 4 Gy) of ultraviolet (h nu <= 7 eV) that selectively creates anion excitons and radiative defects in the anion sublattice. Having used the previously established connection between thermoactivated processes such as thermostimulated exoemission, electroconductivity, and luminescence in the irradiated crystal lattice, the concentrations of exoemission-active centers (EAC) and kinetics parameters of TSEE are calculated. The EAC concentration calculated on a base of the bulk, thermoactivated-recombinational, and band-gap Auger-like exoemission mechanisms, are in satisfactory agreement with the concentration of electron color centers in the irradiated crystals.

Temperature dependence of radiation colloidal centers production and annealing in alkali halide crystals

International Nuclear Information System (INIS)

Kristapson, J.Z.; Ozerskii, V.J.

1981-01-01

The investigation results on temperature dependences of production and annealing of radiation colloidal color centers have been reviewed. In order to produce such centers in NaCl, KCl and KBr crystals the doses of 10 2 -10 4 Mrad as well as irradiation temperatures of 300-600 K and post-irradiation heating of up to 800 K were applied. It has been demonstrated that to produce X-centers, it is necessary to have optimal temperature and initial critical dose during both irradiation and post-irradiation heating of crystals. It has been also found that during annealing hole centers produced are different with regard to thermal stability. The possible recombination mechanisms of hole and electron products of radiolysis during post-irradiation heating has been analyzed [ru

VT Data - VTORTHO Color Imagery (0.15m) 2017, Addison County

Data.gov (United States)

Vermont Center for Geographic Information — (Link to Metadata) This metadata record describes the acquisition and production of 15 centimeter ground sample distance (GSD) natural color and color infrared...

Effect of gamma irradiation on the color, structure and morphology of nickel-doped polyvinyl alcohol films: Alternative use as dosimeter or irradiation indicator

Science.gov (United States)

Raouafi, A.; Daoudi, M.; Jouini, K.; Charradi, K.; Hamzaoui, A. H.; Blaise, P.; Farah, K.; Hosni, F.

2018-06-01

Nickel-doped poly vinyl alcohol (PVA) films were developed for potential application in industrial sectors like radiation processing. We report in this paper the results of an experimental investigation of 60Co source γ-radiation effect on colorimetric, structural and morphological properties of PVA films doped with 0.5% Ni2+ ions (PVA/Ni2+). The PVA/Ni2+ films were irradiated by different gamma-radiation doses varying from 5 to 100 kGy. Color modification of films were studied using L∗, a∗ and b∗ color space measurements as function of the γ-dose and post-irradiation time. The visual change in all samples was verified by microstructure analysis, Fourier transforms infrared (FTIR) spectroscopy, X-Rays diffraction (XRD) and scanning electron microscopy (SEM). The color space exhibited a linear dose response at a dose ranging from 5 to 50 kGy, and then it reached saturation for higher γ-doses. The calculated color changes (ΔE) show a linear dose response relationship from 9.90 to 115.02 in the dose range from 0 to 50 kGy. It showed also the activation of stable color centers. The variability of the color change did not exceed 3% during 80 h (h) post-irradiation. Furthermore, the microstructure analysis evidenced that the color modification due to the optical activation of nickel-oxide (NiO) color center were obtained by complexing Ni2+ ions in irradiated PVA films. The obtained results inspire the possibility to use PVA films for the control process in industrial radiation facilities in dose range 5-50 kGy.

Two-color pump-probe laser spectroscopy instrument with picosecond time-resolved electronic delay and extended scan range

Science.gov (United States)

Yu, Anchi; Ye, Xiong; Ionascu, Dan; Cao, Wenxiang; Champion, Paul M.

2005-11-01

An electronically delayed two-color pump-probe instrument was developed using two synchronized laser systems. The instrument has picosecond time resolution and can perform scans over hundreds of nanoseconds without the beam divergence and walk-off effects that occur using standard spatial delay systems. A unique picosecond Ti :sapphire regenerative amplifier was also constructed without the need for pulse stretching and compressing optics. The picosecond regenerative amplifier has a broad wavelength tuning range, which suggests that it will make a significant contribution to two-color pump-probe experiments. To test this instrument we studied the rotational correlation relaxation of myoglobin (τr=8.2±0.5ns) in water as well as the geminate rebinding kinetics of oxygen to myoglobin (kg1=1.7×1011s-1, kg2=3.4×107s-1). The results are consistent with, and improve upon, previous studies.

Study of Tl0(1) and In0(1) defects in alkaline halides: prototype of a color center as active laser medium

International Nuclear Information System (INIS)

Vieira Junior, N.D.

1986-01-01

The optical properties of the Tl 0 (1) and In 0 (1) centers in Kcl crystals in cation sites of the crystal lattice, perturbed by an adjacent anion vacancy. Emphasis is given to the lowest energy levels. Using a tagging optical absorption technique, the absorption bands were identified. The laser action of Tl 0 (1) center in KCl by pumping with Nd: YAG laser in the lowest energy absorption band was obtained. A simple way to achieve continuous single frequency laser operation using a grating as the sole tuning element is described. It is shown that, by proper choice of cavity parameters, the competing hole burning modes can be completely supressed. Experiments were carried out using Tl 0 (1) centers in KCl as the gain medium. The production of pulses via synchronous pumping of Tl 0 (1) color center in KCl are reported. (author) [pt

Modeling human color categorization: Color discrimination and color memory

OpenAIRE

Heskes, T.; van den Broek, Egon; Lucas, P.; Hendriks, Maria A.; Vuurpijl, L.G.; Puts, M.J.H.; Wiegerinck, W.

2003-01-01

Color matching in Content-Based Image Retrieval is done using a color space and measuring distances between colors. Such an approach yields non-intuitive results for the user. We introduce color categories (or focal colors), determine that they are valid, and use them in two experiments. The experiments conducted prove the difference between color categorization by the cognitive processes color discrimination and color memory. In addition, they yield a Color Look-Up Table, which can improve c...

Superconducting microwave electronics at Lewis Research Center

Science.gov (United States)

Warner, Joseph D.; Bhasin, Kul B.; Leonard, Regis F.

Over the last three years, NASA Lewis Research Center has investigated the application of newly discovered high temperature superconductors to microwave electronics. Using thin films of YBa2Cu3O7-delta and Tl2Ca2Ba2Cu3Ox deposited on a variety of substrates, including strontium titanate, lanthanum gallate, lanthanum aluminate and magnesium oxide, a number of microwave circuits have been fabricated and evaluated. These include a cavity resonator at 60 GHz, microstrip resonators at 35 GHz, a superconducting antenna array at 35 GHz, a dielectric resonator at 9 GHz, and a microstrip filter at 5 GHz. Performance of some of these circuits as well as suggestions for other applications are reported.

Superconducting Microwave Electronics at Lewis Research Center

Science.gov (United States)

Warner, Joseph D.; Bhasin, Kul B.; Leonard, Regis F.

1991-01-01

Over the last three years, NASA Lewis Research Center has investigated the application of newly discovered high temperature superconductors to microwave electronics. Using thin films of YBa2Cu3O7-delta and Tl2Ca2Ba2Cu3Ox deposited on a variety of substrates, including strontium titanate, lanthanum gallate, lanthanum aluminate and magnesium oxide, a number of microwave circuits have been fabricated and evaluated. These include a cavity resonator at 60 GHz, microstrip resonators at 35 GHz, a superconducting antenna array at 35 GHz, a dielectric resonator at 9 GHz, and a microstrip filter at 5 GHz. Performance of some of these circuits as well as suggestions for other applications are reported.

Evaluation of toxicity and removal of color in textile effluent treated with electron beam

International Nuclear Information System (INIS)

Morais, Aline Viana de

2015-01-01

The textile industry is among the main activities Brazil, being relevant in number of jobs, quantity and diversity of products and mainly by the volume of water used in industrial processes and effluent generation. These effluents are complex mixtures which are characterized by the presence of dyes, surfactants, metal sequestering agents, salts and other potentially toxic chemicals for the aquatic biota. Considering the lack of adequate waste management to these treatments, new technologies are essential in highlighting the advanced oxidation processes such as ionizing radiation electron beam. This study includes the preparation of a standard textile effluent chemical laboratory and its treatment by electron beam from electron accelerator in order to reduce the toxicity and intense staining resulting from Cl. Blue 222 dye. The treatment caused a reduction in toxicity to exposed organisms with 34.55% efficiency for the Daphnia similis micro crustacean and 47.83% for Brachionus plicatilis rotifer at a dose of 2.5 kGy. The Vibrio fischeri bacteria obtained better results after treatment with a dose of 5 kGy showing 57.29% efficiency. Color reduction was greater than 90% at a dose of 2.5 kGy. This experiment has also carried out some preliminary tests on the sensitivity of the D. similis and V. fischeri organisms to exposure of some of the products used in this bleaching and dyeing and two water reuse simulations in new textile processing after the treating the effluent with electron beam. (author)

A color magnetic vortex condensate in QCD

International Nuclear Information System (INIS)

Ambjoern, J.; Olesen, P.

1980-03-01

It is shown that there exists a very close analogy between a lattice of vorticies in a superconductor near the critical field and a condensate of color magnetic flux tubes due to the unstable mode in QCD. This analogy makes it possible to identify a dynamical Higgs field in QCD. It is shown that the color magnetic flux tubes are quantized in terms of the center group Z(2) in the SU(2) case. In the case of SU(N) it is possible to select a color direction of the field such that one has Z(N) quantization. (Auth.)

A Moessbauer study of the germanium two-electron donor centers in PbSe

International Nuclear Information System (INIS)

Terukov, E.I.; Khuzhakulov, Eh.S.

2005-01-01

The 73 As( 73 Ge) Moessbauer emission spectroscopy is used for identification of neutral and ionized two-electron germanium centers in PbSe. It is shown that the charge state of antistructural defect 73 Ge, generating in the anion sublattice after 73 As radioactive decay, does not depend on the Fermi level position. In contrast to this, the 73 Ge center in the cation PbSe sublattice represents the electrically active substitution impurity. The emission spectra correspond to the neutral state of the ( 73 Ge 2+ ) donor center in n-type conductors and to the double ionized state of this ( 73 Ge 4+ ) center in p-type conductors [ru

78 FR 16471 - National Cybersecurity Center of Excellence (NCCoE) Secure Exchange of Electronic Health...

Science.gov (United States)

2013-03-15

...-02] National Cybersecurity Center of Excellence (NCCoE) Secure Exchange of Electronic Health...) National Cybersecurity Center of Excellence (NCCoE) invited organizations to provide products and technical.... companies to enter into ``National Cybersecurity Excellence Partnerships'' (NCEPs) in furtherance of the...

Instrumentation at the National Center for Electron Microscopy: the Atomic Resolution Microscope

International Nuclear Information System (INIS)

Gronsky, R.; Thomas, G.

1983-01-01

The Atomic Resolution Microscope (ARM) is one of two unique high voltage electron microscopes at the Lawrence Berkeley Laboratory's National Center for Electron Microscopy (NCEM). The latest results from this new instrument which was manufactured by JEOL, Ltd. to the performance specifications of the NCEM, delivered in January of 1983, and soon to be open to access by the entire microscopy community are given. Details of its history and development are given and its performance specifications are reviewed

Calculation of two-center one-electron molecular integrals with STOs. [BICEN

Energy Technology Data Exchange (ETDEWEB)

Rico, J.F.; Lopez, R.; Paniagua, M.; Ramirez, G. (Universidad Autonoma de Madrid (Spain). Dept. de Quimica Fisica y Quimica Cuantica)

1991-05-01

A program for the calculation of two-center one-electron integrals (overlap, nuclear attraction and kinetic energy) between real Slater-type orbitals (STOs) is reported. The integrals are obtained by recursion over simple auxiliary matrices, whose elements are calculated in terms of further auxiliary functions evaluated in a quick and accurate way. (orig.).

Visible laser radiation from color centers brought on α-Al2O3 by fast electrons

International Nuclear Information System (INIS)

Arutyunyan, V.V.; Gevorkyan, V.A.; Ezoyan, R.K.; Eritsyan, G.N.; Sarkisov, V.Kh.

1988-01-01

A lamp-pumped lasing from colour centres brought on corundum crystals by 50 MeV electrons is reported. Lasing is observed only in an active element sample with C 3 -vector perpendicular l-vector - orientation. The lasing-action threshold was 1200 j. To find out the reasons for the dependence of lasing from the crystal axis C 3 -vector the absorption, excitation and luminescence spectra of crystals bombarded by different doses of fast electrons and with different thermal annealing are investigated. The results of investigation of spectra of additional absorption within the range 400-600 nm, luminescence excitation registered at the wavelength 560 nm and photoluminescence excitation registered at the wavelength 460 nm (F 2 + -centre) are presented. In the luminescence spectrum there are three bands with maxima near 560, 610, 710 nm and a narrow one at 695 nm resulting from uncontrollable admixture Cr 3+ ions. 3 refs.; 3 figs

Modeling human color categorization: Color discrimination and color memory

NARCIS (Netherlands)

Heskes, T.; van den Broek, Egon; Lucas, P.; Hendriks, Maria A.; Vuurpijl, L.G.; Puts, M.J.H.; Wiegerinck, W.

2003-01-01

Color matching in Content-Based Image Retrieval is done using a color space and measuring distances between colors. Such an approach yields non-intuitive results for the user. We introduce color categories (or focal colors), determine that they are valid, and use them in two experiments. The

Influence of mitochondrial efficiency on beef lean color stability

Science.gov (United States)

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...

Image color reduction method for color-defective observers using a color palette composed of 20 particular colors

Science.gov (United States)

Sakamoto, Takashi

2015-01-01

This study describes a color enhancement method that uses a color palette especially designed for protan and deutan defects, commonly known as red-green color blindness. The proposed color reduction method is based on a simple color mapping. Complicated computation and image processing are not required by using the proposed method, and the method can replace protan and deutan confusion (p/d-confusion) colors with protan and deutan safe (p/d-safe) colors. Color palettes for protan and deutan defects proposed by previous studies are composed of few p/d-safe colors. Thus, the colors contained in these palettes are insufficient for replacing colors in photographs. Recently, Ito et al. proposed a p/dsafe color palette composed of 20 particular colors. The author demonstrated that their p/d-safe color palette could be applied to image color reduction in photographs as a means to replace p/d-confusion colors. This study describes the results of the proposed color reduction in photographs that include typical p/d-confusion colors, which can be replaced. After the reduction process is completed, color-defective observers can distinguish these confusion colors.

Photodissociation comprehensive study of OH- on alkali halides and their interaction with colour centers

International Nuclear Information System (INIS)

Gomes, L.

1985-01-01

This work shows that the OH - defect induces changes in the electronics processes of the alkali halides such as in radiation damage and optical cycles of colour centers. Two cases were considered: with the presence of an OH - ion in the (1) excited state and (2) in the ground state; 1) the comprehensive study of resonant OH - photodissociation in several hosts showed that deep traps (for electrons) can be produced from the OH - dissociation. These traps can be effective for the capture of electrons produced in the radiation damage of the lattice as well as for trapping electrons from ionized color centers. It was observed a second channel (new) for the de-excitation of the (OH - )* molecule in KI and RbI. This effect can be effective only when the lattice around the molecule holds a large enough interstitial space. This new mechanism is responsible for the strong production at LNT of F centers and OH 0 molecules at the expenses of OH - defects. Considering the complete investigation of the full cycle it was proposed a phenomenological model that would explain the observed behaviour when one covers a wide variation of lattice parameters (KCl -> RbI); 2) It was verified that the OH - ion present in the lattice induces strong changes in the de-excitation processes of electronic defects with a spread out wave function (like F centers). A change in the reorientation behaviour of excited F 2 and F + 2 centers was also verified. Two main effects should be mentioned: A) The induced de-excitation is very fast and non-radiative on F centers. B) Another type of system investigated (F 2 and F + 2 ) has shown an intense increase of the speed of reorientation of the F 2 and F + 2 excited centers. (autor) [pt

Determination of aberration center of Ronchigram for automated aberration correctors in scanning transmission electron microscopy

Energy Technology Data Exchange (ETDEWEB)

Sannomiya, Takumi, E-mail: sannomiya@mtl.titech.ac.jp [Tokyo Institute of Technology, Ookayama, Tokyo (Japan); Sawada, Hidetaka; Nakamichi, Tomohiro; Hosokawa, Fumio [JEOL Limited, Akishima, Tokyo (Japan); Nakamura, Yoshio; Tanishiro, Yasumasa; Takayanagi, Kunio [Tokyo Institute of Technology, Ookayama, Tokyo (Japan)

2013-12-15

A generic method to determine the aberration center is established, which can be utilized for aberration calculation and axis alignment for aberration corrected electron microscopes. In this method, decentering induced secondary aberrations from inherent primary aberrations are minimized to find the appropriate axis center. The fitness function to find the optimal decentering vector for the axis was defined as a sum of decentering induced secondary aberrations with properly distributed weight values according to the aberration order. Since the appropriate decentering vector is determined from the aberration values calculated at an arbitrary center axis, only one aberration measurement is in principle required to find the center, resulting in /very fast center search. This approach was tested for the Ronchigram based aberration calculation method for aberration corrected scanning transmission electron microscopy. Both in simulation and in experiments, the center search was confirmed to work well although the convergence to find the best axis becomes slower with larger primary aberrations. Such aberration center determination is expected to fully automatize the aberration correction procedures, which used to require pre-alignment of experienced users. This approach is also applicable to automated aperture positioning. - Highlights: • A generic method to determine the aberration center is established for (S)TEM. • Decentering induced secondary aberrations are utilized to find the center. • The method is tested on Ronchigrams both in simulation and experiment. • Proper weighting of the aberration gives a good convergence. • Larger primary aberration results in a slower convergence.

Fractal kinetics of radiation-induced point-defect formation and decay in amorphous insulators: Application to color centers in silica-based optical fibers

Science.gov (United States)

Griscom, David L.

2001-11-01

Formalisms have been developed to express the time evolution of bimolecular processes taking place in fractal spaces. These ``stretched-second-order'' solutions are specifically applicable to radiation-induced electron-hole pairs and/or vacancy-interstitial pairs in insulating glasses. Like the analogous Kohlrausch-type (stretched-first-order) expressions, the present solutions are functions of (kt)β, where 0the new second-order formalism and the familiar Kohlrausch approach have been used to fit experimental data (induced optical absorptions in silica-based glasses monitored at selected wavelengths) that serve as proxies for the numbers of color centers created by γ irradiation and/or destroyed by processes involving thermal, optical, or γ-ray activation. Two material systems were investigated: (1) optical fibers with Ge-doped-silica cores and (2) fibers with low-OH/low-chloride pure-silica cores. Successful fits of the growth curves for the Ge-doped-silica-core fibers at four widely separated dose rates were accomplished using solutions for color-center concentrations, N[(kt)β], which approach steady-state values, Nsat, as t-->∞. The parametrization of these fits reveals some unexpected, and potentially useful, empirical rules regarding the dose-rate dependences of β, k, and Nsat in the fractal regime (0the pure-silica-core fibers as well. In both material systems, there appear to be fractal classical phase transitions at certain threshold values of dose rate, below which the dose-rate dependencies of k and Nsat revert to those specified by classical (β=1) first- or second-order kinetics. For ktthe first- and second-order fractal kinetic growth curves become identical, i.e., N((kt)β)~Atβ, where the coefficient A depends on dose rate but not kinetic order. It is found empirically that A depends on the 3β/2 power of dose rate in both first- and second-order kinetics, thus ``accidentally'' becoming linearly proportional to dose rate in cases where β~2

Polarized Electron Beams for Nuclear Physics at the MIT Bates Accelerator Center

CERN Document Server

Farkhondeh, Manouchehr; Franklin, Wilbur; Ihloff, Ernie; McAllister, Brian; Milner, Richard; North, William; Tschalär, C; Tsentalovich, Evgeni; Wang, Defa; Wang, Dong; Wang, Fuhua; Zolfaghari, Abbasali; Zwart, Townsend; van der Laan, Jan

2005-01-01

The MIT Bates Accelerator Center is delivering highly polarized electron beams to its South Hall Ring for use in Nuclear Physics Experiments. Circulating electron currents in excess of 200 mA with polarization of 70% are scattered from a highly polarized, but very thin atomic beam source deuterium target. At the electron source a compact diode laser creates photoemission of quasi-CW mA pulses of polarized electrons at low duty factors from a strained GaAs photocathode. Refurbished RF transmitters provide power to the 2856 MHz linac, accelerating the beam to 850 MeV in two passes before injection into the South Hall Ring. In the ring a Siberian snake serves to maintain a high degree of longitudinal polarization at the BLAST scattering target. A Compton laser back-scattering polarimeter measures the electron beam polarization with a statistical acuracy of 6% every 15 minutes.

Contribution to the study of the responsable mechanisms by the radiative formation of color centers in doped KBr crystals with alkaline earth impurities

International Nuclear Information System (INIS)

Muccillo, R.

1977-01-01

Experiments utilizing the tecniques Optical Absorption in the visible and ultraviolet spectral regions, thermally Stimulated Depolarization Currents (TSDC) in the 120K - 300K temperature range, and Thermoluminescence in the 290K - 620K temperature range - are perform to study radiative production, and thermal and optical destruction of color centers in Sr-droped KBr crystals. Some of the main results are also obtoned from experiments with Ca-deped KBr crystais [pt

Luminescence and color center distributions in K3YB6O12:Ce3+ phosphor

International Nuclear Information System (INIS)

Yang, Li; Wan, Yingpeng; Weng, Honggen; Huang, Yanlin; Chen, Cuili; Seo, Hyo Jin

2016-01-01

Polycrystalline Ce 3+ -doped K 3 YB 6 O 12 (1–14 mol%) phosphors were prepared by facile chemical sol–gel synthesis. The phase formation of the phosphors was confirmed by x-ray powder diffraction (XRD) analysis. The photoluminescence excitation spectra (PLE), emission spectra (PL) and the luminescence decay curves were tested. Under the near-UV light, the phosphors present the emission from blue color to yellowish green due to the allowed 4 f  –5 d transitions of Ce 3+ ions. The absolute quantum efficiency (QE) of K 3 YB 6 O 12 :Ce 3+ can reach 53% under the excitation of near-UV light. The luminescence thermal quenching of the phosphor was investigated by the temperature-dependent spectra. The crystallographic site of Ce 3+ ions in the lattice was identified and discussed on the basis of luminescence characteristics and structural data. There is only one isolated Ce 3+ center occupying the Y(II) sites in the lightly doped samples presenting a typical doublet emission profile. While the Ce 3+ multi-centers could be created with the enhancement of the doping levels, which could induce the distinct red-shift of the spectra due to the dipole–dipole interactions. The result in this work could be useful for the further investigation of other rare earth ions in this host. (paper)

Influence of Surrounding Colors in the Illuminant-Color Mode on Color Constancy

Directory of Open Access Journals (Sweden)

Kazuho Fukuda

2011-05-01

Full Text Available On color constancy, we showed that brighter surrounding colors had greater influence than dim colors (Uchikawa, Kitazawa, MacLeod, Fukuda, 2010 APCV. Increasing luminance of a stimulus causes the change in appearance from the surface-color to the illuminant-color mode. However it is unknown whether the visual system considers such color appearance mode of surrounding colors to achieve color constancy. We investigated the influence of surrounding colors that appeared illuminant on color constancy. The stimulus was composed of a central test stimulus and surrounding six colors: bright and dim red, green and blue. The observers adjusted the chromaticity of the test stimulus to be appeared as an achromatic surface. The luminance balance of three bright surrounding colors was equalized with that of the optimal colors in three illuminant conditions, then, the luminance of one of the three bright colors was varied in the range beyond the critical luminance of color appearance mode transition. The results showed that increasing luminance of a bright surrounding color shifted the observers' achromatic setting toward its chromaticity, but this effect diminished for the surrounding color in the illuminant-color mode. These results suggest that the visual system considers color appearance mode of surrounding colors to accomplish color constancy.

Can Electron-Rich Oxygen (O2-) Withdraw Electrons from Metal Centers? A DFT Study on Oxoanion-Caged Polyoxometalates.

Science.gov (United States)

Takazaki, Aki; Eda, Kazuo; Osakai, Toshiyuki; Nakajima, Takahito

2017-10-12

The answer to the question "Can electron-rich oxygen (O 2- ) withdraw electrons from metal centers?" is seemingly simple, but how the electron population on the M atom behaves when the O-M distance changes is a matter of controversy. A case study has been conducted for Keggin-type polyoxometalate (POM) complexes, and the first-principles electronic structure calculations were carried out not only for real POM species but also for "hypothetical" ones whose heteroatom was replaced with a point charge. From the results of natural population analysis, it was proven that even an electron-rich O 2- , owing to its larger electronegativity as a neutral atom, withdraws electrons when electron redistribution occurs by the change of the bond length. In the case where O 2- coexists with a cation having a large positive charge (e.g., P 5+ (O 2- ) 4 = [PO 4 ] 3- ), the gross electron population (GEP) on the M atom seemingly increases as the O atom comes closer, but this increment in GEP is not due to the role of the O atom but due to a Coulombic effect of the positive charge located on the cation. Furthermore, it was suggested that not GEP but net electron population (NEP) should be responsible for the redox properties.

Chemical coloring on stainless steel by ultrasonic irradiation.

Science.gov (United States)

Cheng, Zuohui; Xue, Yongqiang; Ju, Hongbin

2018-01-01

To solve the problems of high temperature and non-uniformity of coloring on stainless steel, a new chemical coloring process, applying ultrasonic irradiation to the traditional chemical coloring process, was developed in this paper. The effects of ultrasonic frequency and power density (sound intensity) on chemical coloring on stainless steel were studied. The uniformity of morphology and colors was observed with the help of polarizing microscope and scanning electron microscopy (SEM), and the surface compositions were characterized by X-ray photoelectric spectroscopy (XPS), meanwhile, the wear resistance and the corrosion resistance were investigated, and the effect mechanism of ultrasonic irradiation on chemical coloring was discussed. These results show that in the process of chemical coloring on stainless steel by ultrasonic irradiation, the film composition is the same as the traditional chemical coloring, and this method can significantly enhance the uniformity, the wear and corrosion resistances of the color film and accelerate the coloring rate which makes the coloring temperature reduced to 40°C. The effects of ultrasonic irradiation on the chemical coloring can be attributed to the coloring rate accelerated and the coloring temperature reduced by thermal-effect, the uniformity of coloring film improved by dispersion-effect, and the wear and corrosion resistances of coloring film enhanced by cavitation-effect. Ultrasonic irradiation not only has an extensive application prospect for chemical coloring on stainless steel but also provides an valuable reference for other chemical coloring. Copyright © 2017 Elsevier B.V. All rights reserved.

Electron beam irradiation of textile effluents and non-ionic ethoxylated surfactant for toxicity and color removal

Energy Technology Data Exchange (ETDEWEB)

Sole, Stephanie V. Del; Garcia, Vanessa S.G.; Boiani, Nathalia F.; Rosa, Jorge M.; Andrade e Silva, Leonardo G. de; Borrely, Sueli I., E-mail: vanessagranadeiro@gmail.com, E-mail: steh.vdsole@gmail.com, E-mail: jotarosa@hotmail.com [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); SENAI, Faculdade de Tecnologia Antoine Skaf, Sao Paulo, SP (Brazil)

2017-11-01

Textile industry has an expressive scenario in the world economy and Brazil is the 5{sup th} in the textile production. By 2015, Brazilian textile production represented US $ 39.3 billion, accounting for more than 1.8 million tons of fabric (ABIT, 2017). The effluents from textile industry are highlighted by quantity of wastewater discharged and variety of substances (dyes, bleaching agents, surfactants, salts, acids, among others). Such compounds often prove to be toxic to aquatic biota. This present study aims to assess toxicity of whole effluents, before and after irradiation (by electron beam accelerator, EBI). In addition, the reduction of the effluent color after irradiation is also very important. Daphnia similis and Vibrio fischeri were the biological systems applied for toxicity evaluations. Previous results demonstrated the surfactant as the main toxic compound, in the untreated and irradiated forms, EC 50 = 0.44 ppm ± 0.02 (untreated); EC 50 = 0.46 % ± 0.07 (irradiated). The irradiation was effective in reducing the color of the effluent, starting from 0.5 kGy. EB radiation may be proposed as an alternative treatment for the final effluent from textile processing, mainly for reuse purposes. (author)

Electron beam irradiation of textile effluents and non-ionic ethoxylated surfactant for toxicity and color removal

International Nuclear Information System (INIS)

Sole, Stephanie V. Del; Garcia, Vanessa S.G.; Boiani, Nathalia F.; Rosa, Jorge M.; Andrade e Silva, Leonardo G. de; Borrely, Sueli I.

2017-01-01

Textile industry has an expressive scenario in the world economy and Brazil is the 5"t"h in the textile production. By 2015, Brazilian textile production represented US $ 39.3 billion, accounting for more than 1.8 million tons of fabric (ABIT, 2017). The effluents from textile industry are highlighted by quantity of wastewater discharged and variety of substances (dyes, bleaching agents, surfactants, salts, acids, among others). Such compounds often prove to be toxic to aquatic biota. This present study aims to assess toxicity of whole effluents, before and after irradiation (by electron beam accelerator, EBI). In addition, the reduction of the effluent color after irradiation is also very important. Daphnia similis and Vibrio fischeri were the biological systems applied for toxicity evaluations. Previous results demonstrated the surfactant as the main toxic compound, in the untreated and irradiated forms, EC 50 = 0.44 ppm ± 0.02 (untreated); EC 50 = 0.46 % ± 0.07 (irradiated). The irradiation was effective in reducing the color of the effluent, starting from 0.5 kGy. EB radiation may be proposed as an alternative treatment for the final effluent from textile processing, mainly for reuse purposes. (author)

Clustering of color map pixels: an interactive approach

Science.gov (United States)

Moon, Yiu Sang; Luk, Franklin T.; Yuen, K. N.; Yeung, Hoi Wo

2003-12-01

The demand for digital maps continues to arise as mobile electronic devices become more popular nowadays. Instead of creating the entire map from void, we may convert a scanned paper map into a digital one. Color clustering is the very first step of the conversion process. Currently, most of the existing clustering algorithms are fully automatic. They are fast and efficient but may not work well in map conversion because of the numerous ambiguous issues associated with printed maps. Here we introduce two interactive approaches for color clustering on the map: color clustering with pre-calculated index colors (PCIC) and color clustering with pre-calculated color ranges (PCCR). We also introduce a memory model that could enhance and integrate different image processing techniques for fine-tuning the clustering results. Problems and examples of the algorithms are discussed in the paper.

Model of deep centers formation and reactions in electron irradiated InP

International Nuclear Information System (INIS)

Sibille, A.; Suski, J.; Gilleron, M.

1986-01-01

We present a model of the production of deep centers and their reactions following electron irradiations in InP. We propose that the dominant hole traps in p-InP and electron traps in p + n InP junctions are complexes between shallow acceptors and a common intrinsic entity, the phosphorus interstitial or vacancy. The reactions observed below and above room temperature are then due to a local mobility of this entity, which can be obtained as well by thermal as by electronic stimulation of the reactions. This model implies the long-range migration (at least down to 16 K) of this entity, and explains the strongly different behavior of n-InP compared to p-InP samples

Human attention filters for single colors

Science.gov (United States)

Sun, Peng; Chubb, Charles; Wright, Charles E.; Sperling, George

2016-01-01

The visual images in the eyes contain much more information than the brain can process. An important selection mechanism is feature-based attention (FBA). FBA is best described by attention filters that specify precisely the extent to which items containing attended features are selectively processed and the extent to which items that do not contain the attended features are attenuated. The centroid-judgment paradigm enables quick, precise measurements of such human perceptual attention filters, analogous to transmission measurements of photographic color filters. Subjects use a mouse to locate the centroid—the center of gravity—of a briefly displayed cloud of dots and receive precise feedback. A subset of dots is distinguished by some characteristic, such as a different color, and subjects judge the centroid of only the distinguished subset (e.g., dots of a particular color). The analysis efficiently determines the precise weight in the judged centroid of dots of every color in the display (i.e., the attention filter for the particular attended color in that context). We report 32 attention filters for single colors. Attention filters that discriminate one saturated hue from among seven other equiluminant distractor hues are extraordinarily selective, achieving attended/unattended weight ratios >20:1. Attention filters for selecting a color that differs in saturation or lightness from distractors are much less selective than attention filters for hue (given equal discriminability of the colors), and their filter selectivities are proportional to the discriminability distance of neighboring colors, whereas in the same range hue attention-filter selectivity is virtually independent of discriminabilty. PMID:27791040

On the nature of organic and inorganic centers that bifurcate electrons, coupling exergonic and endergonic oxidation-reduction reactions.

Science.gov (United States)

Peters, John W; Beratan, David N; Schut, Gerrit J; Adams, Michael W W

2018-04-19

Bifurcating electrons to couple endergonic and exergonic electron-transfer reactions has been shown to have a key role in energy conserving redox enzymes. Bifurcating enzymes require a redox center that is capable of directing electron transport along two spatially separate pathways. Research into the nature of electron bifurcating sites indicates that one of the keys is the formation of a low potential oxidation state to satisfy the energetics required of the endergonic half reaction, indicating that any redox center (organic or inorganic) that can exist in multiple oxidation states with sufficiently separated redox potentials should be capable of electron bifurcation. In this Feature Article, we explore a paradigm for bifurcating electrons down independent high and low potential pathways, and describe redox cofactors that have been demonstrated or implicated in driving this unique biochemistry.

Why some colors appear more memorable than others: A model combining categories and particulars in color working memory.

Science.gov (United States)

Bae, Gi-Yeul; Olkkonen, Maria; Allred, Sarah R; Flombaum, Jonathan I

2015-08-01

Categorization with basic color terms is an intuitive and universal aspect of color perception. Yet research on visual working memory capacity has largely assumed that only continuous estimates within color space are relevant to memory. As a result, the influence of color categories on working memory remains unknown. We propose a dual content model of color representation in which color matches to objects that are either present (perception) or absent (memory) integrate category representations along with estimates of specific values on a continuous scale ("particulars"). We develop and test the model through 4 experiments. In a first experiment pair, participants reproduce a color target, both with and without a delay, using a recently influential estimation paradigm. In a second experiment pair, we use standard methods in color perception to identify boundary and focal colors in the stimulus set. The main results are that responses drawn from working memory are significantly biased away from category boundaries and toward category centers. Importantly, the same pattern of results is present without a memory delay. The proposed dual content model parsimoniously explains these results, and it should replace prevailing single content models in studies of visual working memory. More broadly, the model and the results demonstrate how the main consequence of visual working memory maintenance is the amplification of category related biases and stimulus-specific variability that originate in perception. (c) 2015 APA, all rights reserved).

Picture-to-picture switching in full-color thermochromic paper displays

OpenAIRE

Hennerdal, Lars-Olov; Berggren, Magnus

2011-01-01

Presently, we contemplate the merger of paper and electronics in different forms. There is a great desire to further explore this twinning of the information displaying features of printed papers and electronic inks. Here, we report a full-color paperboard display technology comprised of thermochromic and static inks combined with a patterned heater foil. Black and full-color thermochromic ink dots were screen-printed adjacent to, and on top of, static ink dots using a zero-angle mesh and tem...

Photoresponsive Smart Coloration Electrochromic Supercapacitor.

Science.gov (United States)

Yun, Tae Gwang; Kim, Donghyuk; Kim, Yong Ho; Park, Minkyu; Hyun, Seungmin; Han, Seung Min

2017-08-01

Electrochromic devices have been widely adopted in energy saving applications by taking advantage of the electrode coloration, but it is critical to develop a new electrochromic device that can undergo smart coloration and can have a wide spectrum in transmittance in response to input light intensity while also functioning as a rechargeable energy storage system. In this study, a photoresponsive electrochromic supercapacitor based on cellulose-nanofiber/Ag-nanowire/reduced-graphene-oxide/WO 3 -composite electrode that is capable of undergoing "smart" reversible coloration while simultaneously functioning as a reliable energy-storage device is developed. The fabricated device exhibits a high coloration efficiency of 64.8 cm 2 C -1 and electrochemical performance with specific capacitance of 406.0 F g -1 , energy/power densities of 40.6-47.8 Wh kg -1 and 6.8-16.9 kW kg -1 . The electrochromic supercapacitor exhibits excellent cycle reliability, where 75.0% and 94.1% of its coloration efficiency and electrochemical performance is retained, respectively, beyond 10 000 charge-discharge cycles. Cyclic fatigue tests show that the developed device is mechanically durable and suitable for wearable electronics applications. The smart electrochromic supercapacitor system is then integrated with a solar sensor to enable photoresponsive coloration where the transmittance changes in response to varying light intensity. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Electronic structure of deep levels in silicon. A study of gold, magnesium, and iron centers in silicon

International Nuclear Information System (INIS)

Thilderkvist, A. L.

1994-02-01

The electronic structure of gold, magnesium and iron related deep centers in silicon is investigated. Their deep and shallow levels are studied by means of fourier transform spectroscopy, combined with uniaxial stress and Zeeman spectroscopy. The neutral substitutional gold center in silicon is investigated and the center is paramagnetic, S=1/2, with g||≅2.8 and g≅0, and has a static distortion. Reorientation between different equivalent distortions is observed even at 1.9 K. A gold pair center in silicon is studied and several line series, with a zero-phonon line followed by several phonon replicas, are observed. Uniaxial stress and Zeeman results reveal a trigonal symmetry of the center, which together with the high dissociation energy of 1.7 eV suggests that the center consists of two nearest-neighbor substitutional gold atoms. A divacancy model is employed to explain the electronic properties of the center. The interstitial magnesium double donor in silicon in its two charge states Mg o and Mg + is investigated. Deviations in the binding energies of the excited states from those calculated within the effective-mass theory (EMT) are found and explained by a perturbation in the central-cell region. The quadratic Zeeman effect of shallow donors in silicon is analyzed within the framework of the EMT using a numerical approach. The wave functions are calculated in a discrete radial mesh and the Zeeman Hamiltonian has be evaluated for the lowest excited states for fields up to 6 T. The neutral interstitial iron defect in silicon gives rise to two sets of line spectra. The first set arises when an electron is excited to a shallow donor like state where the electron is decoupled from the Fe + core which has a 4 T 1 ground state term. The second set arises when an excited electron of a 1 symmetry is coupled by exchange interaction to the core, yielding at 5 T 1 final state. Experiments determine the multiplet splitting of the 4 T 1 and 5 T 1 states due to spring

Processing of Color Words Activates Color Representations

Science.gov (United States)

Richter, Tobias; Zwaan, Rolf A.

2009-01-01

Two experiments were conducted to investigate whether color representations are routinely activated when color words are processed. Congruency effects of colors and color words were observed in both directions. Lexical decisions on color words were faster when preceding colors matched the color named by the word. Color-discrimination responses…

Color categories and color appearance

Science.gov (United States)

Webster, Michael A.; Kay, Paul

2011-01-01

We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue–green boundary, to test whether chromatic differences across the boundary were perceptually exaggerated. This task did not require overt judgments of the perceived colors, and the tendency to group showed only a weak and inconsistent categorical bias. In a second case, we analyzed results from two prior studies of hue scaling of chromatic stimuli (De Valois, De Valois, Switkes, & Mahon, 1997; Malkoc, Kay, & Webster, 2005), to test whether color appearance changed more rapidly around the blue–green boundary. In this task observers directly judge the perceived color of the stimuli and these judgments tended to show much stronger categorical effects. The differences between these tasks could arise either because different signals mediate color grouping and color appearance, or because linguistic categories might differentially intrude on the response to color and/or on the perception of color. Our results suggest that the interaction between language and color processing may be highly dependent on the specific task and cognitive demands and strategies of the observer, and also highlight pronounced individual differences in the tendency to exhibit categorical responses. PMID:22176751

Mössbauer studies of two-electron centers with negative correlation energy in crystalline and amorphous semiconductors

International Nuclear Information System (INIS)

Bordovsky, G. A.; Nemov, S. A.; Marchenko, A. V.; Seregin, P. P.

2012-01-01

The results of the study of donor U − -centers of tin and germanium in lead chalcogenides by Mössbauer emission spectroscopy are discussed. The published data regarding the identification of amphoteric U − -centers of tin in glassy binary arsenic and germanium chalcogenides using Mössbauer emission spectroscopy, and in multicomponent chalcogenide glasses using Mössbauer absorption spectroscopy are considered. Published data concerning the identification of two-atom U − -centers of copper in lattices of semimetal copper oxides by Mössbauer emission spectroscopy are analyzed. The published data on the detection of spatial inhomogeneity of the Bose-Einstein condensate in superconducting semiconductors and semimetal compounds, and on the existence of the correlation between the electron density in lattice sites and the superconducting transition temperature are presented. The principal possibility of using Mössbauer U − -centers as a tool for studying the Bose-Einstein condensation of electron pairs during the superconducting phase transition in semiconductors and semimetals is considered.

Electronic Chemotherapy Order Entry: A Major Cancer Center's Implementation.

Science.gov (United States)

Sklarin, Nancy T; Granovsky, Svetlana; O'Reilly, Eileen M; Zelenetz, Andrew D

2011-07-01

Implementation of a computerized provider order entry system for complex chemotherapy regimens at a large cancer center required intense effort from a multidisciplinary team of clinical and systems experts with experience in all facets of the chemotherapy process. The online tools had to resemble the paper forms used at the time and parallel the successful established process as well as add new functionality. Close collaboration between the institution and the vendor was necessary. This article summarizes the institutional efforts, challenges, and collaborative processes that facilitated universal chemotherapy computerized electronic order entry across multiple sites during a period of several years.

Is the color trails culture free?

Science.gov (United States)

Fasfous, Ahmed F; Puente, Antonio E; Pérez-Marfil, María Nieves; Cruz-Quintana, Francisco; Peralta-Ramirez, Isabel; Pérez-García, Miguel

2013-11-01

Increasingly clinical neuropsychology has been addressing the effects of culture on neuropsychological functioning. However, that focus has been on comparing performance on standardized tests across two or more groups, often Hispanic. In this study, Arabic children were tested in Morocco using a "culture-free test," Children's Color Trails. Children of different ages and living in rural and urban centers were tested. The results suggest that the Color Trails Test scores from Arab children differed from U.S. norms available. Furthermore, the location of testing and the age of the child were of significance. The role of culture-specific tests was considered.

Loving transgressions: Queer of color bodies, affective ties, transformative community.

Science.gov (United States)

Carrillo Rowe, Aimee; Royster, Francesca T

2017-07-03

This introductory article considers the importance of queer woman of color theorizations of affect in thinking more fully the recent interdisciplinary turn to affect. The affective turn has vitally invited culture and feminist critics to interrogate emotion beyond the individual to examine the political and cultural production of emotion. Even as women of color are often associated with excessive affect, the theoretical contributions women of color make to the field of affect studies are often overlooked. Our introduction and this special issue more broadly examine how this solipsism shapes projects invested in critical knowledge production, as well as the stakes of centering a queer woman of color genealogy. For instance, we argue for the importance of retaining U.S. third-world feminist concepts-like interpellation, oppositional consciousness, and the generative force of negative affects-even as they fall out of favor within affect studies. Centering theory that emerges from the vexed spaces of queer women of color lived experiences generates a vital interdisciplinary conversation that contributes to the ongoing political task of mobilizing affect for social action as a critical praxis. In the articles that follow we see this critical praxis at work in the form of community organizing, music, poetry, and performance art.

Photonic Color Filters Integrated with Organic Solar Cells for Energy Harvesting

KAUST Repository

Park, Hui Joon

2011-09-27

Color filters are indispensable in most color display applications. In most cases, they are chemical pigment-based filters, which produce a particular color by absorbing its complementary color, and the absorbed energy is totally wasted. If the absorbed and wasted energy can be utilized, e.g., to generate electricity, innovative energy-efficient electronic media could be envisioned. Here we show photonic nanostructures incorporated with photovoltaics capable of producing desirable colors in the visible band and utilize the absorbed light to simultaneously generate electrical powers. In contrast to the traditional colorant-based filters, these devices offer great advantages for electro-optic applications. © 2011 American Chemical Society.

Two- and three-dimensional magnetoinductive particle codes with guiding center electron motion

International Nuclear Information System (INIS)

Geary, J.L.; Tajima, T.; Leboeuf, J.N.; Zaidman, E.G.; Han, J.H.

1986-07-01

A magnetoinductive (Darwin) particle simulation model developed for examining low frequency plasma behavior with large time steps is presented. Electron motion perpendicular to the magnetic field is treated as massless keeping only the guiding center motion. Electron motion parallel to the magnetic field retains full inertial effects as does the ion motion. This model has been implemented in two and three dimensions. Computational tests of the equilibrium properties of the code are compared with linear theory and the fluctuation dissipation theorem. This code has been applied to the problems of Alfven wave resonance heating and twist-kink modes

Enhancement of color and clarity in topaz and diamonds by nuclear radiation, safety and security concerns

International Nuclear Information System (INIS)

Shamshad Ahmed

2009-01-01

Inducement of color and clarity in gemstone Topaz, otherwise devoid of these attributes, has been achieved by synergistic utilization of neutron irradiation, electron beam irradiation and heat. The transformation of the colorless, cheaply available topaz into desirable deep blue topaz is a significant value addition, not achievable by other contending techniques .Likewise colorless and unclear diamonds, available in trade at throw away price, have been transformed by neutron irradiation into colored diamonds, known as fancy diamonds. The enhanced gems may possess stable or unstable colors depending on the nature of the color centers produced. In the case of blue topaz and fancy diamonds the colors produced were stable and heating at elevated temperatures can only lead to fading of colors. The enhancement of gems by neutron irradiation is commercially viable provided appropriate equipment and tools are used .In the paper are described the processes of the enhancement of topaz and diamonds along with the instrumentation involved. However, in view of the radioactivity generated as a result of the exposure of gems to the neutrons, and the likelihood of undue exposure of the users, operators etc to the radioactive gems, safety aspects command serious attention. In the paper, the strategies to avoid or to mitigate the radioactivity generated have been discussed. Also documented are the methodologies and the controls to ensure that the radioactive gems are not released before ensuring that the radioactivity, if any, in the irradiated materials is not above the permissible levels in conformity with the international standards. Safety, security and safeguard of these materials are thus appropriately addressed. (Authors)

Laser-induced plasmas in air studied using two-color interferometry

International Nuclear Information System (INIS)

Yang, Zefeng; Wu, Jian; Li, Xingwen; Han, Jiaxun; Jia, Shenli; Qiu, Aici; Wei, Wenfu

2016-01-01

Temporally and spatially resolved density profiles of Cu atoms, electrons, and compressed air, from laser-induced copper plasmas in air, are measured using fast spectral imaging and two-color interferometry. From the intensified CCD images filtered by a narrow-band-pass filter centered at 515.32 nm, the Cu atoms expansion route is estimated and used to determine the position of the fracture surface between the Cu atoms and the air. Results indicate that the Cu atoms density at distances closer to the target (0–0.4 mm) is quite low, with the maximum density appearing at the edge of the plasma's core being ∼4.6 × 10"2"4" m"−"3 at 304 ns. The free electrons are mainly located in the internal region of the plume, which is supposed to have a higher temperature. The density of the shock wave is (4–6) × 10"2"5" m"−"3, corresponding to air compression of a factor of 1.7–2.5.

Laser-induced plasmas in air studied using two-color interferometry

Energy Technology Data Exchange (ETDEWEB)

Yang, Zefeng; Wu, Jian, E-mail: jxjawj@mail.xjtu.edu.cn; Li, Xingwen; Han, Jiaxun; Jia, Shenli; Qiu, Aici [State Key Laboratory of Electrical Insulation and Power Equipment, Xi' an Jiaotong University, Shaanxi 710049 (China); Wei, Wenfu [School of Electrical Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

2016-08-15

Temporally and spatially resolved density profiles of Cu atoms, electrons, and compressed air, from laser-induced copper plasmas in air, are measured using fast spectral imaging and two-color interferometry. From the intensified CCD images filtered by a narrow-band-pass filter centered at 515.32 nm, the Cu atoms expansion route is estimated and used to determine the position of the fracture surface between the Cu atoms and the air. Results indicate that the Cu atoms density at distances closer to the target (0–0.4 mm) is quite low, with the maximum density appearing at the edge of the plasma's core being ∼4.6 × 10{sup 24 }m{sup −3} at 304 ns. The free electrons are mainly located in the internal region of the plume, which is supposed to have a higher temperature. The density of the shock wave is (4–6) × 10{sup 25 }m{sup −3}, corresponding to air compression of a factor of 1.7–2.5.

Electron spin resonance from NV centers in diamonds levitating in an ion trap

International Nuclear Information System (INIS)

Delord, T; Nicolas, L; Schwab, L; Hétet, G

2017-01-01

We report observations of the electron spin resonance (ESR) of nitrogen vacancy centers in diamonds that are levitating in an ion trap. Using a needle Paul trap operating under ambient conditions, we demonstrate efficient microwave driving of the electronic spin and show that the spin properties of deposited diamond particles measured by the ESR are retained in the Paul trap. We also exploit the ESR signal to show angle stability of single trapped mono-crystals, a necessary step towards spin-controlled levitating macroscopic objects. (paper)

For fashion and health (coloring of gems)

International Nuclear Information System (INIS)

Umeda, Iwao

1998-01-01

Artificial coloration of colorless jewel grade diamonds can be made by fast neutron irradiation using a research reactor or high energy electron beam bombardment by a linear accelerator. The irradiated color diamonds are from blue to green. After irradiation, the blue-green diamonds change color to yellow or orange by subsequent annealing using an electric furnace. The colored diamond hue depends on the treatment conditions. Fancy hue can be produced under some suitable conditions. Some special absorption bands in the spectrum obtained by a spectrophotometer can discriminate artificially colored diamonds from natural fancy color diamonds. Diamonds become to be radioactive immediately after irradiation by a reactor, but the radioactivity decay rapidly and become safe after a month. Some imported gems without diamond as blue topaz etc. are sometimes discovered to be radioactive artificially. Cultured pearls are covered by 0.4 mm thick nacreous layer on the pearl nucleus made of fresh-water unionidae thick shell. White pearls turn color to silver by 60 Co γ-ray irradiation. The pearl nucleus contained Mn turns color to brown by irradiation and absorbs red light from reflection on the surface, whereas the nacreous layer is little color change by irradiation because of small quantity of Mn and remains the luster. White pearls turn beautiful blue-silver of like natural color pearls seemingly, by γ-ray irradiation in suitable solution. Cubic zirconia made from ZrO 2 is a man-made colorless crystal looked like a diamond. The crystals turn color to orange by irradiation. (J.P.N)

Do focal colors look particularly "colorful"?

Science.gov (United States)

Witzel, Christoph; Franklin, Anna

2014-04-01

If the most typical red, yellow, green, and blue were particularly colorful (i.e., saturated), they would "jump out to the eye." This would explain why even fundamentally different languages have distinct color terms for these focal colors, and why unique hues play a prominent role in subjective color appearance. In this study, the subjective saturation of 10 colors around each of these focal colors was measured through a pairwise matching task. Results show that subjective saturation changes systematically across hues in a way that is strongly correlated to the visual gamut, and exponentially related to sensitivity but not to focal colors.

Using color management in color document processing

Science.gov (United States)

Nehab, Smadar

1995-04-01

Color Management Systems have been used for several years in Desktop Publishing (DTP) environments. While this development hasn't matured yet, we are already experiencing the next generation of the color imaging revolution-Device Independent Color for the small office/home office (SOHO) environment. Though there are still open technical issues with device independent color matching, they are not the focal point of this paper. This paper discusses two new and crucial aspects in using color management in color document processing: the management of color objects and their associated color rendering methods; a proposal for a precedence order and handshaking protocol among the various software components involved in color document processing. As color peripherals become affordable to the SOHO market, color management also becomes a prerequisite for common document authoring applications such as word processors. The first color management solutions were oriented towards DTP environments whose requirements were largely different. For example, DTP documents are image-centric, as opposed to SOHO documents that are text and charts centric. To achieve optimal reproduction on low-cost SOHO peripherals, it is critical that different color rendering methods are used for the different document object types. The first challenge in using color management of color document processing is the association of rendering methods with object types. As a result of an evolutionary process, color matching solutions are now available as application software, as driver embedded software and as operating system extensions. Consequently, document processing faces a new challenge, the correct selection of the color matching solution while avoiding duplicate color corrections.

Projectile Coulomb center effects on low-energy electron emission from H[sup +][yields]Ne collisions

Energy Technology Data Exchange (ETDEWEB)

Suarez, S. (Centro Atomico Bariloche e Inst. Balseiro, Comision Nacional de Energia Atomica, S.C. de Bariloche, Rio Negro (Argentina)); Garibotti, C. (Centro Atomico Bariloche e Inst. Balseiro, Comision Nacional de Energia Atomica, S.C. de Bariloche, Rio Negro (Argentina) Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina)); Bernardi, G. (Centro Atomico Bariloche e Inst. Balseiro, Comision Nacional de Energia Atomica, S.C. de Bariloche, Rio Negro (Argentina) Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina)); Focke, P. (Centro Atomico Bariloche e Inst. Balseiro, Comision Nacional de Energia Atomica, S.C. de Bariloche, Rio Negro (Argentina)); Meckbach, W. (Centro Atomico Bariloche e Inst. Balseiro, Comision Nacional de Energia Atomica, S.C. de Bariloche, Rio Negro (Argentina) Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET) (Argentina))

1994-03-01

We present doubly differential energy distributions of low-energy electrons emitted in collisions of 106 keV H[sup +] on Ne atoms. We find a relevant dependence of the measured distribution of low-energy electrons on the physical extension of the gas target and discuss a correction procedure. Our measurements enable a quantitative analysis of the shape of the soft electron peak, which is clearly evidenced by measured contour lines. Present results indicate that ''two center effects'' must be considered in order to account for the strong asymmetry of the soft electron peak observed experimentaly. (orig.)

Color maps of X-ray globular clusters

International Nuclear Information System (INIS)

Bailyn, C.D.; Grindlay, J.E.; Cohn, H.; Lugger, P.M.

1988-01-01

The results of a search for optical counterparts to X-ray sources in six globular clusters, 47 Tuc, NGC 1851, NGC 6441, NGC 6624, NGC 6712, and M15, are reported. Maps of the U-B color of the central regions of the clusters were prepared. A candidate for the optical counterpart of the source in NGC 6712 was found, along with a blue region near the X-ray source in 47 Tuc. Upper limits on the colors and magnitudes of possible optical counterparts are reported for the other three clusters. The use of color maps to determine color gradients in globular clusters is explored. It is found that, while such gradients do exist and vary from cluster to cluster, they can be explained by crowding effects. Crude limits are placed on the excess populations of blue objects such as CVs, which have been postulated to be concentrated in the centers of dense clusters. 32 references

Automatic color preference correction for color reproduction

Science.gov (United States)

Tsukada, Masato; Funayama, Chisato; Tajima, Johji

2000-12-01

The reproduction of natural objects in color images has attracted a great deal of attention. Reproduction more pleasing colors of natural objects is one of the methods available to improve image quality. We developed an automatic color correction method to maintain preferred color reproduction for three significant categories: facial skin color, green grass and blue sky. In this method, a representative color in an object area to be corrected is automatically extracted from an input image, and a set of color correction parameters is selected depending on the representative color. The improvement in image quality for reproductions of natural image was more than 93 percent in subjective experiments. These results show the usefulness of our automatic color correction method for the reproduction of preferred colors.

Frequency of color blindness in pre-employment screening in a tertiary health care center in Pakistan.

Science.gov (United States)

Chhipa, Shaukat Ali; Hashmi, Farzeen K; Ali, Shehreen; Kamal, Mustafa; Ahmad, Khabir

2017-01-01

To describe the frequency of color vision deficiency among Pakistani adults presenting for pre-employment health screening in a tertiary care hospital. The cross-sectional study was carried out at the Aga Khan University Hospital, Karachi, and the data was collected for color vision deficiency, age, gender, and job applied for from pre-employment examination during 2013-2014. IBM SPSS 20 was used for statistical analysis. Three thousand four hundred and thirty seven persons underwent pre-employment screening during 2013 and 2014; 1837 (53.44%) were males and 1600 (46.65%) females. The mean age was 29.01 (±6.53) years. A total of 0.9% (32/3437) persons had color vision deficiency with male being 1.4% and female 0.4%. Color vision deficiency was observed in 0.9% of candidates screened for pre-employment health check up in a tertiary care hospital. The color vision deficiency was predominantly present in male individuals.

Functional LH1 antenna complexes influence electron transfer in bacterial photosynthetic reaction centers

NARCIS (Netherlands)

Visschers, R.W.; Vulto, S.I.E.; Jones, M.R.; van Grondelle, R.; Kraayenhof, R.

1999-01-01

The effect of the light harvesting 1 (LH1) antenna complex on the driving force for light-driven electron transfer in the Rhodobacter sphaeroides reaction center has been examined. Equilibrium redox titrations show that the presence of the LH1 antenna complex influences the free energy change for

Functional LH1 antenna complexes influence electron transfer in bacterial photosynthetic reaction centers.

NARCIS (Netherlands)

Visschers, R.W.; Vulto, S.I.E.; Jones, M.R.; van Grondelle, R.; Kraayenhof, R.

1999-01-01

The effect of the light harvesting 1 (LH1) antenna complex on the driving force for light-driven electron transfer in the Rhodobacter sphaeroides reaction center has been examined. Equilibrium redox titrations show that the presence of the LH1 antenna complex influences the free energy change for

Future of laser electrophotographic technology for color document printing

Science.gov (United States)

Shahin, Michael M.

1997-04-01

Recent years have witnessed the development of laser electrophotography as one of the major technologies for document printing, serving a wide range of market applications. With the evolution of color and market demand for color hard copy, electrophotography is again taking center stage to serve the customer need in quality, cost and convenience. Today, electrophotographic technology is used to offer products for color document printing for desktop, mid-volume and high-speed applications. Total cost of ownership, convenience and quality today favor the use of this technology over alternatives in many applications. Development of higher speed color electrophotographic engines demands very high speed, Raster Input Processors and pre-press applications that are expected to become available in the market during the next five years. This presentation will cover the changing environment of office communication and the continuing role of electrophotography in color document printing.

Coloring of synthetic fluorite

International Nuclear Information System (INIS)

Birsoy, R.

1980-01-01

A synthetic fluorite of the Harshaw Chemical Company is analyzed for rare earth elements, yttrium, and sodium. Samples of this fluorite are irradiated with X-rays, γ-rays, neutrons, electrons, protons, and α-particles at different energies, and their absorption spectra are analyzed. Analyzing the thermal bleaching of these radiation-coloured fluorites shows that both, impurities and radiation play a part in the coloration of synthetic fluorite. However, the main contribution comes from the radiation induced lattice defects. In the visible region spectra, the colour centre of the 5800 to 5900 A absorption band is probably mainly related with large aggregates of F-centres. The 5450 and the 5300 A absorption bands are mainly related to monovalent and divalent ion impurities and their association with lattice defects. The 3800 A absorption band seems to be related with F-centre aggregates. However, the contribution from the rare earth elements related complex color centres also plays some part for the production of this absorption band. These results indicate that the color centres of different origin can absorb light at the same wavelength. (author)

Embedding Color Watermarks in Color Images

Directory of Open Access Journals (Sweden)

Wu Tung-Lin

2003-01-01

Full Text Available Robust watermarking with oblivious detection is essential to practical copyright protection of digital images. Effective exploitation of the characteristics of human visual perception to color stimuli helps to develop the watermarking scheme that fills the requirement. In this paper, an oblivious watermarking scheme that embeds color watermarks in color images is proposed. Through color gamut analysis and quantizer design, color watermarks are embedded by modifying quantization indices of color pixels without resulting in perceivable distortion. Only a small amount of information including the specification of color gamut, quantizer stepsize, and color tables is required to extract the watermark. Experimental results show that the proposed watermarking scheme is computationally simple and quite robust in face of various attacks such as cropping, low-pass filtering, white-noise addition, scaling, and JPEG compression with high compression ratios.

Cholesteric Liquid Crystal Based Reflex Color Reflective Displays

Science.gov (United States)

Khan, Asad

2012-02-01

Bistable color cholesteric liquid crystal displays are unique LCDs that exhibit high reflectivity, good contrast, extremely low power operation, and are amenable to versatile roll-to-roll manufacturing. The display technology, now branded as Reflex has been in commercialized products since 1996. It has been the subject of extensive research and development globally by a variety of parties in both academic and industrial settings. Today, the display technology is in volume production for applications such as dedicated eWriters (Boogie Board), full color electronic skins (eSkin), and displays for smart cards. The flexibility comes from polymerization induced phase separation using unique materials unparalleled in any other display technology. The blend of monomers, polymers, cross linkers, and other components along with nematic liquid crystals and chiral dopants is created and processed in such ways so as to enable highly efficient manufactrable displays using ultra thin plastic substrates -- often as thin as 50μm. Other significant aspects include full color by stacking or spatial separation, night vision capability, ultra high resolution, as well as active matrix capabilities. Of particular note is the stacking approach of Reflex based displays to show full color. This approach for reflective color displays is unique to this technology. Owing to high transparency in wavelength bands outside the selective reflection band, three primarily color layers can be stacked on top of each other and reflect without interfering with other layers. This highly surprising architecture enables the highest reflectivity of any other reflective electronic color display technology. The optics, architecture, electro-topics, and process techniques will be discussed. This presentation will focus on the physics of the core technology and color, it's evolution from rigid glass based displays to flexible displays, development of products from the paradigm shifting concepts to consumer

Dependence of high density nitrogen-vacancy center ensemble coherence on electron irradiation doses and annealing time

Science.gov (United States)

Zhang, C.; Yuan, H.; Zhang, N.; Xu, L. X.; Li, B.; Cheng, G. D.; Wang, Y.; Gui, Q.; Fang, J. C.

2017-12-01

Negatively charged nitrogen-vacancy (NV-) center ensembles in diamond have proved to have great potential for use in highly sensitive, small-package solid-state quantum sensors. One way to improve sensitivity is to produce a high-density NV- center ensemble on a large scale with a long coherence lifetime. In this work, the NV- center ensemble is prepared in type-Ib diamond using high energy electron irradiation and annealing, and the transverse relaxation time of the ensemble—T 2—was systematically investigated as a function of the irradiation electron dose and annealing time. Dynamical decoupling sequences were used to characterize T 2. To overcome the problem of low signal-to-noise ratio in T 2 measurement, a coupled strip lines waveguide was used to synchronously manipulate NV- centers along three directions to improve fluorescence signal contrast. Finally, NV- center ensembles with a high concentration of roughly 1015 mm-3 were manipulated within a ~10 µs coherence time. By applying a multi-coupled strip-lines waveguide to improve the effective volume of the diamond, a sub-femtotesla sensitivity for AC field magnetometry can be achieved. The long-coherence high-density large-scale NV- center ensemble in diamond means that types of room-temperature micro-sized solid-state quantum sensors with ultra-high sensitivity can be further developed in the near future.

Color evaluation of computer-generated color rainbow holography

International Nuclear Information System (INIS)

Shi, Yile; Wang, Hui; Wu, Qiong

2013-01-01

A color evaluation approach for computer-generated color rainbow holography (CGCRH) is presented. Firstly, the relationship between color quantities of a computer display and a color computer-generated holography (CCGH) colorimetric system is discussed based on color matching theory. An isochromatic transfer relationship of color quantity and amplitude of object light field is proposed. Secondly, the color reproduction mechanism and factors leading to the color difference between the color object and the holographic image that is reconstructed by CGCRH are analyzed in detail. A quantitative color calculation method for the holographic image reconstructed by CGCRH is given. Finally, general color samples are selected as numerical calculation test targets and the color differences between holographic images and test targets are calculated based on our proposed method. (paper)

Sensory Drive, Color, and Color Vision.

Science.gov (United States)

Price, Trevor D

2017-08-01

Colors often appear to differ in arbitrary ways among related species. However, a fraction of color diversity may be explained because some signals are more easily perceived in one environment rather than another. Models show that not only signals but also the perception of signals should regularly evolve in response to different environments, whether these primarily involve detection of conspecifics or detection of predators and prey. Thus, a deeper understanding of how perception of color correlates with environmental attributes should help generate more predictive models of color divergence. Here, I briefly review our understanding of color vision in vertebrates. Then I focus on opsin spectral tuning and opsin expression, two traits involved in color perception that have become amenable to study. I ask how opsin tuning is correlated with ecological differences, notably the light environment, and how this potentially affects perception of conspecific colors. Although opsin tuning appears to evolve slowly, opsin expression levels are more evolutionarily labile but have been difficult to connect to color perception. The challenge going forward will be to identify how physiological differences involved in color vision, such as opsin expression levels, translate into perceptual differences, the selection pressures that have driven those differences, and ultimately how this may drive evolution of conspecific colors.

Color planner for designers based on color emotions

Science.gov (United States)

Cheng, Ka-Man; Xin, John H.; Taylor, Gail

2002-06-01

During the color perception process, an associated feeling or emotion is induced in our brains, and this kind of emotion is termed as 'color emotion.' The researchers in the field of color emotions have put many efforts in quantifying color emotions with the standard color specifications and evaluating the influence of hue, lightness and chroma to the color emotions of human beings. In this study, a color planner was derived according to these findings so that the correlation of color emotions and standard color specifications was clearly indicated. Since people of different nationalities usually have different color emotions as different cultural and traditional backgrounds, the subjects in this study were all native Hong Kong Chinese and the color emotion words were all written in Chinese language in the visual assessments. Through the color planner, the designers from different areas, no matter fashion, graphic, interior or web site etc., can select suitable colors for inducing target color emotions to the customers or product-users since different colors convey different meanings to them. In addition, the designers can enhance the functionality and increase the attractiveness of their designed products by selecting suitable colors.

Initial color development in radiochromic dye films after a short intense pulse of accelerated electrons

International Nuclear Information System (INIS)

Uribe, R.M.; Barcelo, M.; Rios, J.; McLaughlin, W.L.; Buenfil, A.E.

1990-01-01

The radiation response of different dye precursors in several host plastics has been investigated after a single short-pulse irradiation with 2.5-MeV electrons. It was observed that in most films the radiation-initiated color development proceeds mainly during the first 300 seconds, after such high dose-rate irradiation (∼ 10 12 Gy/s). Absorption spectra show that the main absorption band increases at the expense of a shorter-wavelength precursor absorption band, showing an isosbestic point approximately midway bwetwen the two absorption bands. It was found that a certain combination of dye precursor and host plastic (namely a polyamide containing an aromatic group) constitutes a film which shows a very fast increase in optical density of the main absorption band, making it suitable for immediate dosimetric analysis in very high dose-rate installations. (author)

Coastal Zone Color Scanner

Science.gov (United States)

Johnson, B.

1988-01-01

The Coastal Zone Color Scanner (CZCS) spacecraft ocean color instrument is capable of measuring and mapping global ocean surface chlorophyll concentration. It is a scanning radiometer with multiband capability. With new electronics and some mechanical, and optical re-work, it probably can be made flight worthy. Some additional components of a second flight model are also available. An engineering study and further tests are necessary to determine exactly what effort is required to properly prepare the instrument for spaceflight and the nature of interfaces to prospective spacecraft. The CZCS provides operational instrument capability for monitoring of ocean productivity and currents. It could be a simple, low cost alternative to developing new instruments for ocean color imaging. Researchers have determined that with global ocean color data they can: specify quantitatively the role of oceans in the global carbon cycle and other major biogeochemical cycles; determine the magnitude and variability of annual primary production by marine phytoplankton on a global scale; understand the fate of fluvial nutrients and their possible affect on carbon budgets; elucidate the coupling mechanism between upwelling and large scale patterns in ocean basins; answer questions concerning the large scale distribution and timing of spring blooms in the global ocean; acquire a better understanding of the processes associated with mixing along the edge of eddies, coastal currents, western boundary currents, etc., and acquire global data on marine optical properties.

Creation and characterization of He-related color centers in diamond

Energy Technology Data Exchange (ETDEWEB)

Forneris, J., E-mail: forneris@to.infn.it [Istituto Nazionale di Fisica Nucleare (INFN), Sez. Torino, via P. Giuria 1, 10125 Torino (Italy); Physics Department and “NIS” Inter-departmental Centre - University of Torino, 10125 Torino (Italy); Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM), Sez. Torino, Torino (Italy); Tengattini, A.; Tchernij, S. Ditalia [Physics Department and “NIS” Inter-departmental Centre - University of Torino, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sez. Torino, via P. Giuria 1, 10125 Torino (Italy); Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM), Sez. Torino, Torino (Italy); Picollo, F. [Istituto Nazionale di Fisica Nucleare (INFN), Sez. Torino, via P. Giuria 1, 10125 Torino (Italy); Physics Department and “NIS” Inter-departmental Centre - University of Torino, 10125 Torino (Italy); Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM), Sez. Torino, Torino (Italy); Battiato, A. [Physics Department and “NIS” Inter-departmental Centre - University of Torino, 10125 Torino (Italy); Istituto Nazionale di Fisica Nucleare (INFN), Sez. Torino, via P. Giuria 1, 10125 Torino (Italy); Consorzio Nazionale Interuniversitario per le Scienze Fisiche della Materia (CNISM), Sez. Torino, Torino (Italy); Traina, P.; Degiovanni, I.P.; Moreva, E.; Brida, G. [Istituto Nazionale di Ricerca Metrologica (INRiM), Strada delle Cacce 91, 10135 Torino (Italy); Grilj, V.; Skukan, N.; Jakšić, M. [Ruđer Bošković Institute, Bijenicka 54, P.O. Box 180, 10002 Zagreb (Croatia); and others

2016-11-15

Diamond is a promising material for the development of emerging applications in quantum optics, quantum information and quantum sensing. The fabrication and characterization of novel luminescent defects with suitable opto-physical properties is therefore of primary importance for further advances in these research fields. In this work we report on the investigation in the formation of photoluminescent (PL) defects upon MeV He implantation in diamond. Such color centers, previously reported only in electroluminescence and cathodoluminescence regime, exhibited two sharp emission lines at 536.5 nm and 560.5 nm, without significant phonon sidebands. A strong correlation between the PL intensities of the above-mentioned emission lines and the He implantation fluence was found in the 10{sup 15}–10{sup 17} cm{sup −2} fluence range. The PL emission features were not detected in control samples, i.e. samples that were either unirradiated or irradiated with different ion species (H, C). Therefore, the PL features are attributed to optically active defects in the diamond matrix associated with He impurities. The intensity of the 536.5 nm and 560.5 nm emission lines was investigated as a function of the annealing temperature of the diamond substrate. The emission was observed upon annealing at temperatures higher than 500 °C, at the expenses of the concurrently decreasing neutral-vacancy-related GR1 emission intensity. Therefore, our findings indicate that the luminescence originates from the formation of a stable lattice defect. Finally, photoluminescence from He-related defects was observed under different laser excitations wavelengths (i.e. 532 nm and 405 nm), thus providing promising evidence of a broad spectral range for optical stimulation. - Highlights: • Creation of luminescent defects in single-crystal diamond upon He implantation. • First observation of photoluminescent emission from two sharp emission lines at 536.5 and 560.5 nm. • Attribution of the

Creation and characterization of He-related color centers in diamond

International Nuclear Information System (INIS)

Forneris, J.; Tengattini, A.; Tchernij, S. Ditalia; Picollo, F.; Battiato, A.; Traina, P.; Degiovanni, I.P.; Moreva, E.; Brida, G.; Grilj, V.; Skukan, N.; Jakšić, M.

2016-01-01

Diamond is a promising material for the development of emerging applications in quantum optics, quantum information and quantum sensing. The fabrication and characterization of novel luminescent defects with suitable opto-physical properties is therefore of primary importance for further advances in these research fields. In this work we report on the investigation in the formation of photoluminescent (PL) defects upon MeV He implantation in diamond. Such color centers, previously reported only in electroluminescence and cathodoluminescence regime, exhibited two sharp emission lines at 536.5 nm and 560.5 nm, without significant phonon sidebands. A strong correlation between the PL intensities of the above-mentioned emission lines and the He implantation fluence was found in the 10 15 –10 17 cm −2 fluence range. The PL emission features were not detected in control samples, i.e. samples that were either unirradiated or irradiated with different ion species (H, C). Therefore, the PL features are attributed to optically active defects in the diamond matrix associated with He impurities. The intensity of the 536.5 nm and 560.5 nm emission lines was investigated as a function of the annealing temperature of the diamond substrate. The emission was observed upon annealing at temperatures higher than 500 °C, at the expenses of the concurrently decreasing neutral-vacancy-related GR1 emission intensity. Therefore, our findings indicate that the luminescence originates from the formation of a stable lattice defect. Finally, photoluminescence from He-related defects was observed under different laser excitations wavelengths (i.e. 532 nm and 405 nm), thus providing promising evidence of a broad spectral range for optical stimulation. - Highlights: • Creation of luminescent defects in single-crystal diamond upon He implantation. • First observation of photoluminescent emission from two sharp emission lines at 536.5 and 560.5 nm. • Attribution of the emission lines to

Colorization-Based RGB-White Color Interpolation using Color Filter Array with Randomly Sampled Pattern.

Science.gov (United States)

Oh, Paul; Lee, Sukho; Kang, Moon Gi

2017-06-28

Recently, several RGB-White (RGBW) color filter arrays (CFAs) have been proposed, which have extra white (W) pixels in the filter array that are highly sensitive. Due to the high sensitivity, the W pixels have better SNR (Signal to Noise Ratio) characteristics than other color pixels in the filter array, especially, in low light conditions. However, most of the RGBW CFAs are designed so that the acquired RGBW pattern image can be converted into the conventional Bayer pattern image, which is then again converted into the final color image by using conventional demosaicing methods, i.e., color interpolation techniques. In this paper, we propose a new RGBW color filter array based on a totally different color interpolation technique, the colorization algorithm. The colorization algorithm was initially proposed for colorizing a gray image into a color image using a small number of color seeds. Here, we adopt this algorithm as a color interpolation technique, so that the RGBW color filter array can be designed with a very large number of W pixels to make the most of the highly sensitive characteristics of the W channel. The resulting RGBW color filter array has a pattern with a large proportion of W pixels, while the small-numbered RGB pixels are randomly distributed over the array. The colorization algorithm makes it possible to reconstruct the colors from such a small number of RGB values. Due to the large proportion of W pixels, the reconstructed color image has a high SNR value, especially higher than those of conventional CFAs in low light condition. Experimental results show that many important information which are not perceived in color images reconstructed with conventional CFAs are perceived in the images reconstructed with the proposed method.

Of colored numbers and numbered colors: interactive processes in grapheme-color synesthesia.

Science.gov (United States)

Gebuis, Titia; Nijboer, Tanja C W; van der Smagt, Maarten J

2009-01-01

Grapheme-color synesthetes experience a specific color when they see a grapheme but they do not report to perceive a grapheme when a color is presented. In this study, we investigate whether color can still evoke number-processes even when a vivid number experience is absent. We used color-number and number-color priming, both revealing faster responses in congruent compared to incongruent conditions. Interestingly, the congruency effect was of similar magnitude for both conditions, and a numerical distance effect was present only in the color-number priming task. In addition, a priming task in which synesthetes had to judge the parity of a colored number revealed faster responses in parity congruent than in parity incongruent trials. These combined results demonstrate that synesthesia is indeed bi-directional and of similar strength in both directions. Furthermore, they illustrate the precise nature of these interactions and show that the direction of these interactions is determined by task demands, not by the more vividly experienced aspect of the stimulus.

Cortical Activation during Landmark-Centered vs. Gaze-Centered Memory of Saccade Targets in the Human: An FMRI Study

Directory of Open Access Journals (Sweden)

Ying Chen

2017-06-01

Full Text Available A remembered saccade target could be encoded in egocentric coordinates such as gaze-centered, or relative to some external allocentric landmark that is independent of the target or gaze (landmark-centered. In comparison to egocentric mechanisms, very little is known about such a landmark-centered representation. Here, we used an event-related fMRI design to identify brain areas supporting these two types of spatial coding (i.e., landmark-centered vs. gaze-centered for target memory during the Delay phase where only target location, not saccade direction, was specified. The paradigm included three tasks with identical display of visual stimuli but different auditory instructions: Landmark Saccade (remember target location relative to a visual landmark, independent of gaze, Control Saccade (remember original target location relative to gaze fixation, independent of the landmark, and a non-spatial control, Color Report (report target color. During the Delay phase, the Control and Landmark Saccade tasks activated overlapping areas in posterior parietal cortex (PPC and frontal cortex as compared to the color control, but with higher activation in PPC for target coding in the Control Saccade task and higher activation in temporal and occipital cortex for target coding in Landmark Saccade task. Gaze-centered directional selectivity was observed in superior occipital gyrus and inferior occipital gyrus, whereas landmark-centered directional selectivity was observed in precuneus and midposterior intraparietal sulcus. During the Response phase after saccade direction was specified, the parietofrontal network in the left hemisphere showed higher activation for rightward than leftward saccades. Our results suggest that cortical activation for coding saccade target direction relative to a visual landmark differs from gaze-centered directional selectivity for target memory, from the mechanisms for other types of allocentric tasks, and from the directionally

Recombination centers and electrical characteristics in silicon power p-i-n diodes irradiated with high energy electrons

International Nuclear Information System (INIS)

Fuochi, P.G.; Martelli, A.; Passerini, B.; Zambelli, M.

1988-01-01

Recombination centers introduced by irradiation with 12 MeV electrons in large area silicon diodes with p-i-n structure are studied with the Deep Level Transient Spectroscopy technique (DLTS). The effects of these levels on the electrical characteristics of the devices are related to their position Esub(t) in the silicon forbidden gap, their concentration and their electron capture cross section. Changes of defect configuration during an annealing process at 360 0 C have been observed and a detailed analysis of the DLTS spectra has shown a complex defect pattern. Four major recombination centers have been identified: Esub(c) - Esub(t) = 0.17 eV, Esub(c) - Esub(t) = 0.19 eV, Esub(c) -Esub(t) 0.31 eV, Esub(c) - Esub(t) = 0.39 eV, where Esub(c) is the energy corresponding to the lower limit of the conduction band. The first energy level, known as A-center, is the dominant recombination level controlling the minority carrier lifetime after room temperature irradiation. As the annealing proceeds the center at Esub(c) - Esub(t) = 0.31 eV becomes the dominant one. The complex structure of the centers has been studied and demonstrated with the aid of proper modelling implemented on a set of numerical simulation tools. In this way it has been possible to analyze more accurately the defect kinetics during annealing. The study of the defect behaviour during the annealing process has resulted in an improved application of electron irradiation as a standard production technique in the manufacturing process of high power devices. (author)

Laser-plasma acceleration with multi-color pulse stacks: Designer electron beams for advanced radiation sources

Science.gov (United States)

Kalmykov, Serge; Shadwick, Bradley; Ghebregziabher, Isaac; Davoine, Xavier

2015-11-01

Photon engineering offers new avenues to coherently control electron beam phase space on a femtosecond time scale. It enables generation of high-quality beams at a kHz-scale repetition rate. Reducing the peak pulse power (and thus the average laser power) is the key to effectively exercise such control. A stepwise negative chirp, synthesized by incoherently stacking collinear sub-Joule pulses from conventional CPA, affords a micron-scale bandwidth. It is sufficient to prevent rapid compression of the pulse into an optical shock, while delaying electron dephasing. This extends electron energy far beyond the limits suggested by accepted scalings (beyond 1 GeV in a 3 mm plasma), without compromising beam quality. In addition, acceleration with a stacked pulse in a channel favorably modifies electron beam on a femtosecond time scale, controllably producing synchronized sequences of 100 kA-scale, quasi-monoenergetic bunches. These comb-like, designer GeV electron beams are ideal drivers of polychromatic, tunable inverse Thomson γ-ray sources. The work of SYK and BAS is supported by the US DOE Grant DE-SC0008382 and NSF Grant PHY-1104683. Inverse Thomson scattering simulations were completed utilizing the Holland Computing Center of the University of Nebraska.

The number of k-colorings of a graph on a fixed surface

DEFF Research Database (Denmark)

Thomassen, Carsten

2006-01-01

We prove that, for every fixed surface S, there exists a largest positive constant c such that every 5-colorable graph with n vertices on S has at least c center dot 2(n) distinct 5-colorings. This is best possible in the sense that, for each sufficiently large natural number n, there is a graph ...

Precision of synesthetic color matching resembles that for recollected colors rather than physical colors.

Science.gov (United States)

Arnold, Derek H; Wegener, Signy V; Brown, Francesca; Mattingley, Jason B

2012-10-01

Grapheme-color synesthesia is an atypical condition in which individuals experience sensations of color when reading printed graphemes such as letters and digits. For some grapheme-color synesthetes, seeing a printed grapheme triggers a sensation of color, but hearing the name of a grapheme does not. This dissociation allowed us to compare the precision with which synesthetes are able to match their color experiences triggered by visible graphemes, with the precision of their matches for recalled colors based on the same graphemes spoken aloud. In six synesthetes, color matching for printed graphemes was equally variable relative to recalled experiences. In a control experiment, synesthetes and age-matched controls either matched the color of a circular patch while it was visible on a screen, or they judged its color from memory after it had disappeared. Both synesthetes and controls were more variable when matching from memory, and the variance of synesthetes' recalled color judgments matched that associated with their synesthetic judgments for visible graphemes in the first experiment. Results suggest that synesthetic experiences of color triggered by achromatic graphemes are analogous to recollections of color.

Color Terms and Color Concepts

Science.gov (United States)

Davidoff, Jules

2006-01-01

In their lead articles, both Kowalski and Zimiles (2006) and O'Hanlon and Roberson (2006) declare a general relation between color term knowledge and the ability to conceptually represent color. Kowalski and Zimiles, in particular, argue for a priority for the conceptual representation in color term acquisition. The complexities of the interaction…

Visual color matching system based on RGB LED light source

Science.gov (United States)

Sun, Lei; Huang, Qingmei; Feng, Chen; Li, Wei; Wang, Chaofeng

2018-01-01

In order to study the property and performance of LED as RGB primary color light sources on color mixture in visual psychophysical experiments, and to find out the difference between LED light source and traditional light source, a visual color matching experiment system based on LED light sources as RGB primary colors has been built. By simulating traditional experiment of metameric color matching in CIE 1931 RGB color system, it can be used for visual color matching experiments to obtain a set of the spectral tristimulus values which we often call color-matching functions (CMFs). This system consists of three parts: a monochromatic light part using blazed grating, a light mixing part where the summation of 3 LED illuminations are to be visually matched with a monochromatic illumination, and a visual observation part. The three narrow band LEDs used have dominant wavelengths of 640 nm (red), 522 nm (green) and 458 nm (blue) respectively and their intensities can be controlled independently. After the calibration of wavelength and luminance of LED sources with a spectrophotometer, a series of visual color matching experiments have been carried out by 5 observers. The results are compared with those from CIE 1931 RGB color system, and have been used to compute an average locus for the spectral colors in the color triangle, with white at the center. It has been shown that the use of LED is feasible and has the advantages of easy control, good stability and low cost.

Electronic states of on- and off-center donors in quantum rings of finite width

International Nuclear Information System (INIS)

Lima, R.P.A.; Amado, M.

2008-01-01

The electronic states of a hydrogenic donor in two-dimensional quantum rings are calculated by taking into account the finite width of the potential well in the ring. In addition, a strong magnetic field is applied perpendicular to the quantum ring. Using the effective-mass approximation at the Γ valley, the radial Hamiltonian for the envelope-function is exactly diagonalized in the case of on-center donors. The corresponding energy levels for different angular momenta are studied as a function of the applied magnetic field. In the case of off-center donors, a perturbation approach is considered and its limitations are discussed. Finally, we calculate the absorption spectra and oscillator strength for different intraband transitions, specifically for on-center donors

Electronic transitions in quantum dots and rings induced by inhomogeneous off-centered light beams.

Science.gov (United States)

Quinteiro, G F; Lucero, A O; Tamborenea, P I

2010-12-22

We theoretically investigate the effect of inhomogeneous light beams with (twisted light) and without (plane-wave light) orbital angular momentum on semiconductor-based nanostructures, when the symmetry axes of the beam and the nanostructure are displaced parallel to each other. Exact analytical results are obtained by expanding the off-centered light field in terms of the appropriate light modes centered around the nanostructure. We demonstrate how electronic transitions involving the transfer of different amounts of orbital angular momentum are switched on and off as a function of the separation between the axes of the beam and the system. In particular, we show that even off-centered plane-wave beams induce transitions such that the angular momenta of the initial and final states are different.

Color Categories and Color Appearance

Science.gov (United States)

Webster, Michael A.; Kay, Paul

2012-01-01

We examined categorical effects in color appearance in two tasks, which in part differed in the extent to which color naming was explicitly required for the response. In one, we measured the effects of color differences on perceptual grouping for hues that spanned the blue-green boundary, to test whether chromatic differences across the boundary…

Reduction of Aflatoxins in Apricot Kernels by Electronic and Manual Color Sorting

Directory of Open Access Journals (Sweden)

Rosanna Zivoli

2016-01-01

Full Text Available The efficacy of color sorting on reducing aflatoxin levels in shelled apricot kernels was assessed. Naturally-contaminated kernels were submitted to an electronic optical sorter or blanched, peeled, and manually sorted to visually identify and sort discolored kernels (dark and spotted from healthy ones. The samples obtained from the two sorting approaches were ground, homogenized, and analysed by HPLC-FLD for their aflatoxin content. A mass balance approach was used to measure the distribution of aflatoxins in the collected fractions. Aflatoxin B1 and B2 were identified and quantitated in all collected fractions at levels ranging from 1.7 to 22,451.5 µg/kg of AFB1 + AFB2, whereas AFG1 and AFG2 were not detected. Excellent results were obtained by manual sorting of peeled kernels since the removal of discolored kernels (2.6%–19.9% of total peeled kernels removed 97.3%–99.5% of total aflatoxins. The combination of peeling and visual/manual separation of discolored kernels is a feasible strategy to remove 97%–99% of aflatoxins accumulated in naturally-contaminated samples. Electronic optical sorter gave highly variable results since the amount of AFB1 + AFB2 measured in rejected fractions (15%–18% of total kernels ranged from 13% to 59% of total aflatoxins. An improved immunoaffinity-based HPLC-FLD method having low limits of detection for the four aflatoxins (0.01–0.05 µg/kg was developed and used to monitor the occurrence of aflatoxins in 47 commercial products containing apricot kernels and/or almonds commercialized in Italy. Low aflatoxin levels were found in 38% of the tested samples and ranged from 0.06 to 1.50 μg/kg for AFB1 and from 0.06 to 1.79 μg/kg for total aflatoxins.

Color Memory of University Students: Influence of Color Experience and Color Characteristic

Science.gov (United States)

Bynum, Carlisle; Epps, Helen H.; Kaya, Naz

2006-01-01

The ability to select a previously viewed color specimen from an array of specimens that differ in hue, value, or chroma varies among individuals, and may be related to one's basic color discrimination ability or to prior experience with color. This study investigated short-term color memory of 40 college students, 20 of whom were interior design…

Memory for color reactivates color processing region.

Science.gov (United States)

Slotnick, Scott D

2009-11-25

Memory is thought to be constructive in nature, where features processed in different cortical regions are synthesized during retrieval. In an effort to support this constructive memory framework, the present functional magnetic resonance imaging study assessed whether memory for color reactivated color processing regions. During encoding, participants were presented with colored and gray abstract shapes. During retrieval, old and new shapes were presented in gray and participants responded 'old-colored', 'old-gray', or 'new'. Within color perception regions, color memory related activity was observed in the left fusiform gyrus, adjacent to the collateral sulcus. A retinotopic mapping analysis indicated this activity occurred within color processing region V8. The present feature specific evidence provides compelling support for a constructive view of memory.

Electron spin-lattice relaxation of low-symmetry Ni.sup.2+./sup. centers in LiF

Czech Academy of Sciences Publication Activity Database

Azamat, Dmitry; Badalyan, A. G.; Dejneka, Alexandr; Jastrabík, Lubomír; Lančok, Ján

2014-01-01

Roč. 104, č. 25 (2014), "252902-1"-"252902-4" ISSN 0003-6951 R&D Projects: GA MŠk(CZ) LM2011029; GA TA ČR TA01010517; GA ČR GAP108/12/1941 Grant - others:SAFMAT(XE) CZ.2.16/3.1.00/22132 Institutional support: RVO:68378271 Keywords : Ni 2+ centers * LiF single crystals * electron spin-lattice relaxation * electron spin echo technique Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.302, year: 2014

Color change of gemstones by exposure to gamma rays

Energy Technology Data Exchange (ETDEWEB)

Lima, Giovanna L.C. de; Lameiras, Fernando S., E-mail: giovannalarissa17@hotmail.com, E-mail: fsl@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

2015-07-01

A gem is appreciated by collectors and, when polished, widely used for jewelry manufacturing. For example, when quartz naturally or artificially acquires a color it becomes a gemstone (smoky quartz, morion, citrine, amethyst, or prasyolite). The presence of chromophore elements in a quartz sample was analysed by Fourier transform infrared spectrometry (FTIR). With a semi-quantitative analysis of the absorption FTIR spectra, it was possible to predict if colorless quartz has the potential to develop color when exposed to ionizing radiation and heat. Specific absorption bands show the presence of chromophore elements in quartz such as aluminum, iron, hydrogen, sodium, or lithium. Considering the ratio of the heights of the absorption bands of these elements, it was possible to predict the color quartz can develop. Samples of irradiated dark and light violet fluorites were analyzed by FTIR and energy-dispersive X-rays spectroscopy. The light violet samples has higher content of calcium relative to fluorine, as well higher content of hydroxyl, probably replacing fluorine in crystal lattice. Hydroxyls cannot be precursors of F color centers, which are the cause of violet color in fluorite, explaining the light violet color of hydroxyl-rich samples. (author)

Color change of gemstones by exposure to gamma rays

International Nuclear Information System (INIS)

Lima, Giovanna L.C. de; Lameiras, Fernando S.

2015-01-01

A gem is appreciated by collectors and, when polished, widely used for jewelry manufacturing. For example, when quartz naturally or artificially acquires a color it becomes a gemstone (smoky quartz, morion, citrine, amethyst, or prasyolite). The presence of chromophore elements in a quartz sample was analysed by Fourier transform infrared spectrometry (FTIR). With a semi-quantitative analysis of the absorption FTIR spectra, it was possible to predict if colorless quartz has the potential to develop color when exposed to ionizing radiation and heat. Specific absorption bands show the presence of chromophore elements in quartz such as aluminum, iron, hydrogen, sodium, or lithium. Considering the ratio of the heights of the absorption bands of these elements, it was possible to predict the color quartz can develop. Samples of irradiated dark and light violet fluorites were analyzed by FTIR and energy-dispersive X-rays spectroscopy. The light violet samples has higher content of calcium relative to fluorine, as well higher content of hydroxyl, probably replacing fluorine in crystal lattice. Hydroxyls cannot be precursors of F color centers, which are the cause of violet color in fluorite, explaining the light violet color of hydroxyl-rich samples. (author)

Advanced microlens and color filter process technology for the high-efficiency CMOS and CCD image sensors

Science.gov (United States)

Fan, Yang-Tung; Peng, Chiou-Shian; Chu, Cheng-Yu

2000-12-01

New markets are emerging for digital electronic image device, especially in visual communications, PC camera, mobile/cell phone, security system, toys, vehicle image system and computer peripherals for document capture. To enable one-chip image system that image sensor is with a full digital interface, can make image capture devices in our daily lives. Adding a color filter to such image sensor in a pattern of mosaics pixel or wide stripes can make image more real and colorful. We can say 'color filter makes the life more colorful color filter is? Color filter means can filter image light source except the color with specific wavelength and transmittance that is same as color filter itself. Color filter process is coating and patterning green, red and blue (or cyan, magenta and yellow) mosaic resists onto matched pixel in image sensing array pixels. According to the signal caught from each pixel, we can figure out the environment image picture. Widely use of digital electronic camera and multimedia applications today makes the feature of color filter becoming bright. Although it has challenge but it is very worthy to develop the process of color filter. We provide the best service on shorter cycle time, excellent color quality, high and stable yield. The key issues of advanced color process have to be solved and implemented are planarization and micro-lens technology. Lost of key points of color filter process technology have to consider will also be described in this paper.

Walter Reed Army Medical Center's Internet-based electronic health portal.

Science.gov (United States)

Abbott, Kevin C; Boocks, Carl E; Sun, Zhengyi; Boal, Thomas R; Poropatich, Ronald K

2003-12-01

Use of the World Wide Web (WWW) and electronic media to facilitate medical care has been the subject of many reports in the popular press. However, few reports have documented the results of implementing electronic health portals for essential medical tasks, such as prescription refills and appointments. At Walter Reed Army Medical Center, "Search & Learn" medical information, Internet-based prescription refills and patient appointments were established in January 2001. A multiphase retrospective analysis was conducted to determine the use of the "Search & Learn" medical information and the relative number of prescription refills and appointments conducted via the WWW compared with conventional methods. From January 2001 to May 2002, there were 34,741 refills and 819 appointments made over the Internet compared with 2,275,112 refills and approximately 500,000 appointments made conventionally. WWW activity accounted for 1.52% of refills and 0.16% of appointments. There was a steady increase in this percentage over the time of the analysis. In April of 2002, the monthly average of online refills had risen to 4.57% and online appointments were at 0.27%. Online refills were projected to account for 10% of all prescriptions in 2 years. The "Search & Learn" medical information portion of our web site received 147,429 unique visits during this same time frame, which was an average of 326 visitors per day. WWW-based methods of conducting essential medical tasks accounted for a small but rapidly increasing percentage of total activity at Walter Reed Army Medical Center. Subsequent phases of analysis will assess demographic and geographic factors and aid in the design of future systems to increase use of the Internet-based systems.

Vacancy-impurity centers in diamond: prospects for synthesis and applications

Science.gov (United States)

Ekimov, E. A.; Kondrin, M. V.

2017-06-01

The bright luminescence of impurity-vacancy complexes, combined with high chemical and radiation resistance, makes diamond an attractive platform for the production of single-photon emitters and luminescent biomarkers for applications in nanoelectronics and medicine. Two representatives of this kind of defects in diamond, silicon-vacancy (SiV) and germanium-vacancy (GeV) centers, are discussed in this review; their similarities and differences are demonstrated in terms of the more thoroughly studied nitrogen-vacancy (NV) complexes. The recent discovery of GeV luminescent centers opens a unique opportunity for the controlled synthesis of single-photon emitters in nanodiamonds. We demonstrate prospects for the high-pressure high-temperature (HPHT) technique to create single-photon emitters, not only as an auxiliary to chemical vapor deposition (CVD) and ion-implantation methods but also as a primary synthesis tool for producing color centers in nanodiamonds. Besides practical applications, comparative studies of these two complexes, which belong to the same structural class of defects, have a fundamental importance for deeper understanding of shelving levels, the electronic structure, and optical properties of these centers. In conclusion, we discuss several open problems regarding the structure, charge state, and practical application of these centers, which still require a solution.

Using Single Colors and Color Pairs to Communicate Basic Tastes II: Foreground-Background Color Combinations.

Science.gov (United States)

Woods, Andy T; Marmolejo-Ramos, Fernando; Velasco, Carlos; Spence, Charles

2016-01-01

People associate basic tastes (e.g., sweet, sour, bitter, and salty) with specific colors (e.g., pink or red, green or yellow, black or purple, and white or blue). In the present study, we investigated whether a color bordered by another color (either the same or different) would give rise to stronger taste associations relative to a single patch of color. We replicate previous findings, highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. On occasion, color pairs were found to communicate taste expectations more consistently than were single color patches. Furthermore, and in contrast to a recent study in which the color pairs were shown side-by-side, participants took no longer to match the color pairs with tastes than the single colors (they had taken twice as long to respond to the color pairs in the previous study). Possible reasons for these results are discussed, and potential applications for the results, and for the testing methodology developed, are outlined.

Molecular electronics of a single photosystem I reaction center: Studies with scanning tunneling microscopy and spectroscopy

Energy Technology Data Exchange (ETDEWEB)

Lee, I.; Lee, J.W.; Warmack, R.J.; Allison, D.P.; Greenbaum, E. [Oak Ridge National Lab., TN (United States)

1995-03-14

Thylakoids and photosystem I (PSI) reaction centers were imaged by scanning tunneling microscopy. The thylakoids were isolated from spinach chloroplasts, and PSI reaction centers were extracted from thylakoid membranes. Because thylakoids are relatively thick nonconductors, they were sputter-coated with Pd/Au before imaging. PSI photosynthetic centers and chemically platinized PSI were investigated without sputter-coating. They were mounted on flat gold substrates that had been treated with mercaptoacetic acid to help bind the proteins. With tunneling spectroscopy, the PSI centers displayed a semiconductor-like response with a band gap of 1.8 eV. Lightly platinized (platinized for 1 hr) centers displayed diode-like conduction that resulted in dramatic contrast changes between images taken with opposite bias voltages. The electronic properties of this system were stable under long-term storage. 42 refs., 7 figs.

Colorism/Neo-Colorism

Science.gov (United States)

Snell, Joel

2017-01-01

There are numerous aspects to being non-Caucasian that may not be known by Whites. Persons of color suggest folks who are African, South Americans, Native Americans, Biracial, Asians and others. The question is what do these individuals feel relative to their color and facial characteristics. Eugene Robinson suggest that the future favorable color…

How To Control Color Appearance With Instrumentation

Science.gov (United States)

Burns, Margaret E.

1980-05-01

Colorimetry, as defined by the International Commission on Illumination, is the measurement of colors, made possible by the properties of the eye and based on a set of conventions. Instrumentation for measuring object color, therefore, must be based on a human observer. The intent is to design an instrument that in effect responds as a person would, so that research development, production control and quality control areas have some means of assessing the acceptability of the appearance of a product. Investigations of a human observer's psychological response to color, and the manner in which visual observations are made, give the instrument designer and manufacturer data necessary to answer two questions: a. How can we put numbers (instrument read-out) on a perception that occurs in the brain of the observer? b. What can we learn from examination of a visual observing situation that will guide us in our design of an instrumental simulation of this situation? Involving as it does our own daily, almost unconscious, practice of making judgments concerning the things we see, the design and manufacture of color measurement instruments is an exceedingly interesting field. The advances being made concurrently today in research concerning human color vision and in optical and electronic technology will make possible increasingly useful instrumentation for quality control of product color.

Luminance contours can gate afterimage colors and "real" colors.

Science.gov (United States)

Anstis, Stuart; Vergeer, Mark; Van Lier, Rob

2012-09-06

It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The color of the afterimage depends on two adapting colors, those both inside and outside the test. Here, we further explore this phenomenon and show that the color-contour interactions shown for afterimage colors also occur for "real" colors. We argue that similar mechanisms apply for both types of stimulation.

Using Single Colors and Color Pairs to Communicate Basic Tastes II: Foreground–Background Color Combinations

Science.gov (United States)

Marmolejo-Ramos, Fernando; Velasco, Carlos; Spence, Charles

2016-01-01

People associate basic tastes (e.g., sweet, sour, bitter, and salty) with specific colors (e.g., pink or red, green or yellow, black or purple, and white or blue). In the present study, we investigated whether a color bordered by another color (either the same or different) would give rise to stronger taste associations relative to a single patch of color. We replicate previous findings, highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. On occasion, color pairs were found to communicate taste expectations more consistently than were single color patches. Furthermore, and in contrast to a recent study in which the color pairs were shown side-by-side, participants took no longer to match the color pairs with tastes than the single colors (they had taken twice as long to respond to the color pairs in the previous study). Possible reasons for these results are discussed, and potential applications for the results, and for the testing methodology developed, are outlined. PMID:27708752

Postpartum unconscious dynamics emerging from the Lüscher color test in Ethiopian women.

Science.gov (United States)

Zanardo, Vincenzo; Gabrieli, Catia; Volpe, Francesca; Savio, Francesca; Straface, Gianluca; Soldera, Gino

2017-06-01

The aim of this study was to explore the feasibility of the Lüscher color test (LCT), a psychological instrument based on theory that colors are selected in unconscious way and that the color sensory perception of color is objective and universal. The research has involved 24 Ethiopian women, which delivered at the Getche Health Center in Gurage. It seemed to be relevant for the majority of Ethiopian women identify the rejected color (58.66%), the gray, than the favorite color, the yellow 33.33%). The yellow color suggests that they better express their personality in a physical context, while the gray color indicates that they want to live this experience intensely. This exploratory work lays the foundations for further studies in disadvantaged women, both in developing low-income Countries as well as in industrialized Countries characterized by an high level of emigration, and for clinical applications by the complete LCT version.

Effects of irradiation on color and lipid oxidation of prosciutto

International Nuclear Information System (INIS)

Kong Qiulian; Qi Wenyuan; Yue Ling; Chen Zhijun; Bao Yingzi; Dai Xudong; Xu Yun

2011-01-01

This study dealt with the effect of irradiation on the color, ordor and lipid oxidation of prosciutto crudo. The hams were irradiated by γ-ray and electronic beam (EB). Changes of color, ordor, TBA value (TBARS), peroxide value (POV), carbonyl value and conjugated diene value were analyzed and compared with nonirradiated hams. Results showed that color index (a * ) of control, γ-ray irradiated and EB irradiated were 14.39, 9.45 and 11.71 respectively. γ-ray irradiation had been shown to have apparently detrimental effect on the color and ordor of hams, while EB irradiation had little detrimental effect. Irradiation increased POV and conjugated diene value, but the amounts of lipid oxidation products (TBARS, carbonyl value) were less than nonirradiated hams. (authors)

Epidemiological trends in electronic cigarette exposures reported to U.S. Poison Centers.

Science.gov (United States)

Vakkalanka, J P; Hardison, L S; Holstege, C P

2014-06-01

The Centers for Disease Control and Prevention (CDC) has reported an increase in electronic cigarette (e-cigarette) use in both adults and adolescents. Poison Center calls provide data on exposures pertaining to e-cigarette devices and components (including nicotine-refill cartridges), potentially identifying epidemiological trends in reported exposures over time. To characterize the trends in e-cigarette exposures reported to United States (U.S.) Poison Centers between 01 June 2010 and 30 September 2013. We obtained data from the American Association of Poison Control Centers (AAPCC) for all exposures involving e-cigarettes reported to the National Poison Data System (NPDS) by U.S. Poison Centers and described trends in exposures over time, demographics, geographical characteristics, clinical effects and outcomes, management site, and exposure route. A total of 1,700 exposures were reported to Poison Centers during this time. The most frequent age groups were children 5 years or below with 717 (42.2%) exposures and adults ages 20-39 years with 466 (27.4%) exposures. Temporal trends showed an increase of 1.36 exposures per month [95% CI: 1.16-1.56] from June 2010 through December 2012, after which exposures increased by 9.60 per month [95% CI: 8.64-10.55] from January through September 2013. The majority of patients who were followed reported that they had only minor effects. The majority of exposures to e-cigarette devices and components occurred in children of 5 years or below due to accidental exposure. Based on the available data, the reported exposures have resulted in minimal toxicity. Calls to Poison Centers regarding these products have rapidly increased since 2010, and continued surveillance may show changes in the epidemiological trends surrounding e-cigarette exposures.

Color adaptation induced from linguistic description of color.

Directory of Open Access Journals (Sweden)

Liling Zheng

Full Text Available Recent theories propose that language comprehension can influence perception at the low level of perceptual system. Here, we used an adaptation paradigm to test whether processing language caused color adaptation in the visual system. After prolonged exposure to a color linguistic context, which depicted red, green, or non-specific color scenes, participants immediately performed a color detection task, indicating whether they saw a green color square in the middle of a white screen or not. We found that participants were more likely to perceive the green color square after listening to discourses denoting red compared to discourses denoting green or conveying non-specific color information, revealing that language comprehension caused an adaptation aftereffect at the perceptual level. Therefore, semantic representation of color may have a common neural substrate with color perception. These results are in line with the simulation view of embodied language comprehension theory, which predicts that processing language reactivates the sensorimotor systems that are engaged during real experience.

Location Model for Distribution Centers for Fulfilling Electronic Orders of Fresh Foods under Uncertain Demand

Directory of Open Access Journals (Sweden)

Hao Zhang

2017-01-01

Full Text Available The problem of locating distribution centers for delivering fresh food as a part of electronic commerce is a strategic decision problem for enterprises. This paper establishes a model for locating distribution centers that considers the uncertainty of customer demands for fresh goods in terms of time-sensitiveness and freshness. Based on the methodology of robust optimization in dealing with uncertain problems, this paper optimizes the location model in discrete demand probabilistic scenarios. In this paper, an improved fruit fly optimization algorithm is proposed to solve the distribution center location problem. An example is given to show that the proposed model and algorithm are robust and can effectively handle the complications caused by uncertain demand. The model proposed in this paper proves valuable both theoretically and practically in the selection of locations of distribution centers.

Sharing Our Unheard Voices: Perceptions of the Lived Experience of Teachers of Color

Science.gov (United States)

Berrios, Darline

2016-01-01

In public education, approximately 80% of teachers in the United States are White, yet close to half of the student population are students of color (U.S. Department of Education, 2011). Gaps in teacher diversity compared with students of color are found in every state across the country (Center for American Progress, 2011). In 2004, the National…

Development of a Free-Electron Laser Center and Research in Medicine, Biology and Materials Science,

Science.gov (United States)

1992-05-14

the reduced electron- larons cause localized distortions in an ionic lattice lattice coupling strength leads to molecule emission, which are... syndrome . Health Science Center at San Antonio and the University Buerger’s disease, palmar hyperhidrosis, frostbite and of Mi.imi School of Medicine, Miami

Shift Colors

Science.gov (United States)

Publications & News Shift Colors Pages default Sign In NPC Logo Banner : Shift Colors Search Navy Personnel Command > Reference Library > Publications & News > Shift Colors Top Link Bar Navy Personnel Library Expand Reference Library Quick Launch Shift Colors Shift Colors Archives Mailing Address How to

Controlling nonsequential double ionization of Ne with parallel-polarized two-color laser pulses.

Science.gov (United States)

Luo, Siqiang; Ma, Xiaomeng; Xie, Hui; Li, Min; Zhou, Yueming; Cao, Wei; Lu, Peixiang

2018-05-14

We measure the recoil-ion momentum distributions from nonsequential double ionization of Ne by two-color laser pulses consisting of a strong 800-nm field and a weak 400-nm field with parallel polarizations. The ion momentum spectra show pronounced asymmetries in the emission direction, which depend sensitively on the relative phase of the two-color components. Moreover, the peak of the doubly charged ion momentum distribution shifts gradually with the relative phase. The shifted range is much larger than the maximal vector potential of the 400-nm laser field. Those features are well recaptured by a semiclassical model. Through analyzing the correlated electron dynamics, we found that the energy sharing between the two electrons is extremely unequal at the instant of recollison. We further show that the shift of the ion momentum corresponds to the change of the recollision time in the two-color laser field. By tuning the relative phase of the two-color components, the recollision time is controlled with attosecond precision.

Synthesis and Electrophoretic Properties of Novel Nanoparticles for Colored Electronic Ink and e-Paper Applications.

Science.gov (United States)

Jablonski, Christelle; Grundler, Gerhard; Pieles, Uwe; Stebler, Simon; Oehrlein, Reinhold; Szamel, Zbigniew

2016-01-01

A new approach based on non-pigmented, stable colored nanoparticles able to migrate upon application of an electrical field (10-60 V) has been developed for the improvement of the color brightness of e-displays. The scientific challenges comprised the development of efficient syntheses of tri- and bifunctional dendrimers including branching points for further extension and individual decoration with dye (yellow, magenta, cyan). The covalent attachment of these scaffolds to silica nanoparticles was performed via hydrosilylation and final in situ charging generated attractive silica shells for the substractive CMY color space model.

Natural Colorants: Food Colorants from Natural Sources.

Science.gov (United States)

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.

Efficient and color-saturated inverted bottom-emitting organic light-emitting devices with a semi-transparent metal-assisted electron injection layer

Energy Technology Data Exchange (ETDEWEB)

Ho, Meng-Huan, E-mail: kinneas.ac94g@nctu.edu.t [Department of Applied Chemistry, National Chiao Tung University, 210 R, CPT Building, 1001 Ta Hsueh Road, Hsinchu 300, Taiwan (China); Wu, Chang-Yen [Department of Photonics, National Chiao Tung University, Hsinchu 300, Taiwan (China); Chen, Teng-Ming [Department of Applied Chemistry, National Chiao Tung University, 210 R, CPT Building, 1001 Ta Hsueh Road, Hsinchu 300, Taiwan (China); Chen, Chin H. [Display Institute, Microelectronics and Information Systems Research Center, National Chiao Tung University, Hsinchu 300, Taiwan (China)

2011-01-15

We report the development of highly efficient and color-saturated green fluorescent 10-(2-benzothiazolyl)-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H, 11H-benzo[l]pyrano-[6,7,8-ij]quinolizin-11-one dye-doped inverted bottom-emitting organic light-emitting diode (IBOLED). This was enabled by the insertion of a silver (Ag) based semi-transparent metal-assisted electron injection layer between the ITO cathode and n-doped electron transporting layer. This IBOLED with ITO/Ag bilayer cathode with its synergistic microcavity effect achieved luminous efficiencies of 20.7 cd/A and 12.4 lm/W and a saturated CIE{sub x,y} of (0.22, 0.72) at 20 mA/cm{sup 2}, which are twice better than those of the conventional OLED and have over 60% improvement on IBOLED without ITO/Ag bilayer cathode.

A new approach to dual-color two-photon microscopy with fluorescent proteins

Directory of Open Access Journals (Sweden)

Rebane Aleks

2010-02-01

Full Text Available Abstract Background Two-photon dual-color imaging of tissues and cells labeled with fluorescent proteins (FPs is challenging because most two-photon microscopes only provide one laser excitation wavelength at a time. At present, methods for two-photon dual-color imaging are limited due to the requirement of large differences in Stokes shifts between the FPs used and their low two-photon absorption (2PA efficiency. Results Here we present a new method of dual-color two-photon microscopy that uses the simultaneous excitation of the lowest-energy electronic transition of a blue fluorescent protein and a higher-energy electronic transition of a red fluorescent protein. Conclusion Our method does not require large differences in Stokes shifts and can be extended to a variety of FP pairs with larger 2PA efficiency and more optimal imaging properties.

Colors, colored overlays, and reading skills

Directory of Open Access Journals (Sweden)

Arcangelo eUccula

2014-07-01

Full Text Available In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e. who experience eyestrain and/or visual distortions – e.g. color, shape or movement illusions – while reading. This condition would interest the 12-14% of the general population and up to the 46% of the dyslexic population. Thus, colored overlays have been largely employed as a remedy for some aspects of the difficulties in reading experienced by dyslexic individuals, as fluency and speed. Despite the wide use of colored overlays, how they exert their effects has not been made clear yet. Also, according to some researchers, the results supporting the efficacy of colored overlays as a tool for helping readers are at least controversial. Furthermore, the very nature of the Meares-Irlen syndrome has been questioned. Here we provide a concise, critical review of the literature.

Precision of Synesthetic Color Matching Resembles That for Recollected Colors Rather than Physical Colors

Science.gov (United States)

Arnold, Derek H.; Wegener, Signy V.; Brown, Francesca; Mattingley, Jason B.

2012-01-01

Grapheme-color synesthesia is an atypical condition in which individuals experience sensations of color when reading printed graphemes such as letters and digits. For some grapheme-color synesthetes, seeing a printed grapheme triggers a sensation of color, but "hearing" the name of a grapheme does not. This dissociation allowed us to…

Flare-related color effects in UV Ceti stars

International Nuclear Information System (INIS)

Flesch, T.R.

1975-01-01

The UV Ceti flare stars YZ CMi, BD+16 0 2708, EV Lac, and AD Leo were monitored photoelectrically for flare activity with the 76 centimeter reflecting telescope of the University of Florida's Rosemary Hill Observatory. Observations were carried out from January, 1973 to April, 1975. The instrumentation allowed simultaneous readings to be taken at 3500, 4632, and 6496A with a time resolution of 2 seconds. A total of 15 major events were observed, with 14 of these being observed in all three colors. All events showed the classical fast rise and slower decline that is typical of this type of activity. One event showed peculiar behavior in the red bandpass that may indicate strong dependence of the flare light in some cases on line emission. The data were applied to the fast electron model of flare activity proposed by Gurzadyan. Several serious inconsistencies in the theory were found that would not have been evident in single-channel monitoring. No event could be fitted in all three colors using consistent values of the unknown parameters in the theory. The most serious deficiencies in the theory were the wavelength dependence of the optical depth of the electron cloud and the lack of treatment of line emission behavior. Differential color indices for flare light are calculated and are shown to be essentially constant throughout the entire event for the stronger flares. A color-color plot of the flare light at maximum reveals that 11 of the flares show a linear relation. This relation indicates that the smaller the u-b index, the larger is the b-r index. This is probably directly involved with line emission during flare events. Future research possibilities are discussed, with spectroscopic studies and simultaneous multicolor observations being stressed

Color Difference Threshold of Chromostereopsis Induced by Flat Display Emission

Directory of Open Access Journals (Sweden)

Maris eOzolinsh

2015-04-01

Full Text Available The study of chromostereopsis has gained attention in the backdrop of the use of computer displays in daily life. In this context, we analyze the illusory depth sense using planar color images presented on a computer screen. We determine the color difference threshold required to induce an illusory sense of depth psychometrically using a constant stimuli paradigm. Isoluminant stimuli are presented on a computer screen, which stimuli are aligned along the blue-red line in the computer display CIE xyY color chart. Stereo disparity is generated by increasing the color difference between the central and surrounding areas of the stimuli with both areas consisting of random dots on a black background. The observed altering of illusory dept sense, thus also stereo disparity is validated using the center-of-gravity model. The induced illusory sense of the depth effect undergoes color reversal upon varying the binocular lateral eye pupil covering conditions (lateral or medial. Analysis of the retinal image point spread function for the display red and blue pixel radiation validates the altering of chromostereopsis retinal disparity achieved by increasing the color difference, and also the chromostereopsis color reversal caused by varying the eye pupil covering conditions.

Color Analysis

Science.gov (United States)

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.

Studies on the radiation-induced coloration mechanism of the cellulose triacetate film dosimeter

International Nuclear Information System (INIS)

Matsuda, Koji; Nagai, Siro

1991-01-01

The species responsible for the coloration of the cellulose triacetate (CTA) film dosemeter have been studied using ultraviolet, electron spin resonance, infrared and gas chromatographic techniques. The post-irradiation change in the optical density at 280 nm indicates that the coloration occurs not only during irradiation (in situ coloration) but also after irradiation (post-irradiation coloration) and that in situ coloration is due to unstable and stable components. The species responsible for the unstable component of in situ coloration are ascribed to the radicals produced from CTA molecules and those for the stable component to the radiolysis products from CTA and triphenyl phosphate contained in the dosimeter. On the other hand, post-irradiation coloration is attributed to the formation of carbonyl groups in CTA molecules, which is induced by reaction with NO 2 produced by irradiation of air. (author)

Pulse Radiolysis Studies of Temperature Dependent Electron Transfers among Redox Centers in ba(3)-Cytochrome c Oxidase from Thermus thermophilus

DEFF Research Database (Denmark)

Farver, Ole; Wherland, Scot; Antholine, William E

2010-01-01

The functioning of cytochrome c oxidases involves orchestration of long-range electron transfer (ET) events among the four redox active metal centers. We report the temperature dependence of electron transfer from the Cu(A)(r) site to the low-spin heme-(a)b(o) site, i.e., Cu(A)(r) + heme-a(b)(o) ......The functioning of cytochrome c oxidases involves orchestration of long-range electron transfer (ET) events among the four redox active metal centers. We report the temperature dependence of electron transfer from the Cu(A)(r) site to the low-spin heme-(a)b(o) site, i.e., Cu(A)(r) + heme...... in cytochrome ba(3) had no effect on the rate of this reaction whereas the II-Met160Leu Cu(A)-mutation was slower by an amount corresponding to a decreased driving force of ∼0.06 eV. The structures support the presence of a common, electron-conducting "wire" between Cu(A) and heme-a(b). The transfer...

Gamma coloration of mixed crystals of KCl-KBr doped with Pb2+

International Nuclear Information System (INIS)

Cruz Z, E.; Negron, A.; Ramos A, A.; Ramos B, S.; Hernandez A, J.; Jaque, F; Murrieta S, H.

2001-01-01

The amount of the first stage coloration in KCl 1-x Br x doped with Pb 2+ has been investigated as a function of the dose rate and impurity concentration. For a dose rate of 12.88 kGy/h, the F color center production was independent of the quantity of Pb 2+ , and varied according to the ratio KCl/KBr. At a proportion of 50% of each halogen the typical stages were observed. However, if the dose rate is less than 3.22 kGy/h, the coloration production depends on the quantity of Pb 2+ . (author)

Benchmark calculations of excess electrons in water cluster cavities: balancing the addition of atom-centered diffuse functions versus floating diffuse functions.

Science.gov (United States)

Zhang, Changzhe; Bu, Yuxiang

2016-09-14

Diffuse functions have been proved to be especially crucial for the accurate characterization of excess electrons which are usually bound weakly in intermolecular zones far away from the nuclei. To examine the effects of diffuse functions on the nature of the cavity-shaped excess electrons in water cluster surroundings, both the HOMO and LUMO distributions, vertical detachment energies (VDEs) and visible absorption spectra of two selected (H2O)24(-) isomers are investigated in the present work. Two main types of diffuse functions are considered in calculations including the Pople-style atom-centered diffuse functions and the ghost-atom-based floating diffuse functions. It is found that augmentation of atom-centered diffuse functions contributes to a better description of the HOMO (corresponding to the VDE convergence), in agreement with previous studies, but also leads to unreasonable diffuse characters of the LUMO with significant red-shifts in the visible spectra, which is against the conventional point of view that the more the diffuse functions, the better the results. The issue of designing extra floating functions for excess electrons has also been systematically discussed, which indicates that the floating diffuse functions are necessary not only for reducing the computational cost but also for improving both the HOMO and LUMO accuracy. Thus, the basis sets with a combination of partial atom-centered diffuse functions and floating diffuse functions are recommended for a reliable description of the weakly bound electrons. This work presents an efficient way for characterizing the electronic properties of weakly bound electrons accurately by balancing the addition of atom-centered diffuse functions and floating diffuse functions and also by balancing the computational cost and accuracy of the calculated results, and thus is very useful in the relevant calculations of various solvated electron systems and weakly bound anionic systems.

Evaluation of Maxim Module-Integrated Electronics at the DOE Regional Test Centers: Preprint

Energy Technology Data Exchange (ETDEWEB)

Deline, C.; Sekulic, B.; Stein, J.; Barkaszi, S.; Yang, J.; Kahn, S.

2014-07-01

Module-embedded power electronics developed by Maxim Integrated are under evaluation through a partnership with the Department of Energy's Regional Test Center (RTC) program. Field deployments of both conventional modules and electronics-enhanced modules are designed to quantify the performance advantage of Maxim's products under different amounts of inter-row shading, and their ability to be deployed at a greater ground-coverage-ratio than conventional modules. Simulations in PVSYST have quantified the predicted performance difference between conventional modules and Maxim's modules from inter-row shading. Initial performance results have identified diffuse irradiance losses at tighter row spacing for both the Maxim and conventional modules. Comparisons with published models show good agreement with models predicting the greatest diffuse irradiance losses. At tighter row spacing, all of the strings equipped with embedded power electronics outperformed their conventional peers. An even greater performance advantage is predicted to occur in the winter months when the amount of inter-row shading mismatch is at a maximum.

Size-controlled fluorescent nanodiamonds: A facile method of fabrication and color-center counting

KAUST Repository

Mahfouz, Remi; Floyd, Daniel L.; Peng, Wei; Choy, Jennifer; Lončar, Marko; Bakr, Osman

2013-01-01

findings suggest that nanocrystal size separation by DGU may be used to control the number of defects per nanocrystal. The efficient approaches described herein to control and quantify DCCs are valuable to researchers as they explore applications for color

Coloration of chromium-doped yttrium aluminum garnet single-crystal fibers using a divalent codopant

International Nuclear Information System (INIS)

Tissue, B.M.; Jia, W.; Lu, L.; Yen, W.M.

1991-01-01

We have grown single-crystal fibers of Cr:YAG and Cr,Ca:YAG under oxidizing and reducing conditions by the laser-heated-pedestal-growth method. The Cr:YAG crystals were light green due to Cr 3+ in octahedral sites, while the Cr,Ca:YAG crystals were brown. The presence of the divalent codopant was the dominant factor determining the coloration in these single-crystal fibers, while the oxidizing power of the growth atmosphere had little effect on the coloration. The Cr,Ca:YAG had a broad absorption band centered at 1.03 μm and fluoresced from 1.1 to 1.7 μm, with a room-temperature lifetime of 3.5 μs. The presence of both chromium and a divalent codopant were necessary to create the optically-active center which produces the near-infrared emission. Doping with only Ca 2+ created a different coloration with absorption in the blue and ultraviolet. The coloration in the Cr,Ca:YAG is attributed to Cr 4+ and is produced in as-grown crystals without irradiation or annealing, as has been necessary in previous work

Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams

Science.gov (United States)

Piccinini, M.; Ambrosini, F.; Ampollini, A.; Picardi, L.; Ronsivalle, C.; Bonfigli, F.; Libera, S.; Nichelatti, E.; Vincenti, M. A.; Montereali, R. M.

2015-06-01

Systematic irradiation of thermally evaporated 0.8 μm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7 MeV energies, produced by a linear accelerator, in a fluence range from 1011 to 1015 protons/cm2. The visible photoluminescence spectra of radiation-induced F2 and F3+ laser active color centers, which possess almost overlapping absorption bands at about 450 nm, were measured under laser pumping at 458 nm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 103 to about 106 Gy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping.

Color Memory

OpenAIRE

Pate, Monica; Raclariu, Ana-Maria; Strominger, Andrew

2017-01-01

A transient color flux across null infinity in classical Yang-Mills theory is considered. It is shown that a pair of test `quarks' initially in a color singlet generically acquire net color as a result of the flux. A nonlinear formula is derived for the relative color rotation of the quarks. For weak color flux the formula linearizes to the Fourier transform of the soft gluon theorem. This color memory effect is the Yang-Mills analog of the gravitational memory effect.

Photochemistry and reactions of OH- defects and F centers in alkali halides

International Nuclear Information System (INIS)

Morato, S.P.; Luety, F.

1978-01-01

Aditively colored KCl:OH - crystals showed under a combined UV and VIS irradiation, a nearly complete and irreversible destruction of all F centers and visible absorption in the crystal. Only upon heating the crystal above 650 0 C the F center coloration becomes partially restored. The photodissociation of the OH - (under UV light) together with the photoionization of the F center (under VIS light) produces a not effects where all the F centers are converted into U centers. These photoreactions produces high contrast visible images that are completely stable under light at RT. Besides the optical information storage aspect of this effect these photoreaction s can also be used for controlled production of Usub(A) centers if the crystal also contains a foreign metallic impurity such a Na + ion [pt

Color Algebras

Science.gov (United States)

Mulligan, Jeffrey B.

2017-01-01

A color algebra refers to a system for computing sums and products of colors, analogous to additive and subtractive color mixtures. The difficulty addressed here is the fact that, because of metamerism, we cannot know with certainty the spectrum that produced a particular color solely on the basis of sensory data. Knowledge of the spectrum is not required to compute additive mixture of colors, but is critical for subtractive (multiplicative) mixture. Therefore, we cannot predict with certainty the multiplicative interactions between colors based solely on sensory data. There are two potential applications of a color algebra: first, to aid modeling phenomena of human visual perception, such as color constancy and transparency; and, second, to provide better models of the interactions of lights and surfaces for computer graphics rendering.

Electronics for dummies

CERN Document Server

Shamieh

2015-01-01

Explore the basic concepts of electronics, build your electronics workbench, and begin creating fun electronics projects right away! Electronics For Dummies, 3rd Edition is your guide to the world of electronics. Spanning circuitry, wiring, robotics, transmitters, amplifiers, and more, this book demystifies electricity basics and beyond. The third edition offers new content revised to reflect the latest advancements in the electronics field, and it offers full color project examples to spark your creativity and inspire you to put your new skills to use! Packed with projects that can be comple

All-Dielectric Full-Color Printing with TiO2 Metasurfaces.

Science.gov (United States)

Sun, Shang; Zhou, Zhenxing; Zhang, Chen; Gao, Yisheng; Duan, Zonghui; Xiao, Shumin; Song, Qinghai

2017-05-23

Recently, color generation in resonant nanostructures have been intensively studied. Despite of their exciting progresses, the structural colors are usually generated by the plasmonic resonances of metallic nanoparticles. Due to the inherent plasmon damping, such plasmonic nanostructures are usually hard to create very distinct color impressions. Here we utilize the concept of metasurfaces to produce all-dielectric, low-loss, and high-resolution structural colors. We have fabricated TiO 2 metasurfaces with electron-beam lithography and a very simple lift-off process. The optical characterizations showed that the TiO 2 metasurfaces with different unit sizes could generate high reflection peaks at designed wavelengths. The maximal reflectance was as high as 64% with full width at half-maximum (fwhm) around 30 nm. Consequently, distinct colors have been observed in bright field and the generated colors covered the entire visible spectral range. The detailed numerical analysis shows that the distinct colors were generated by the electric resonance and magnetic resonances in TiO 2 metasurfaces. Based on the unique properties of magnetic resonances, distinct colors have been observed in bright field when the metasurfaces were reduced to a 4 × 4 array, giving a spatial resolution around 16000 dpi. Considering the cost, stability, and CMOS-compatibility, this research will be important for the structural colors to reach real-world industrial applications.

Opponent-Color Fusion of Multi-Sensor Imagery: Visible, IR and SAR

National Research Council Canada - National Science Library

Waxman, A

1998-01-01

.... Building on the work reported in two of our earlier papers from IRIS Passive Sensors 1996, we show how opponent-color processing and center-surround shunting neural networks can be used to develop...

Color-Blind Racism, Color-Blind Theology, and Church Practices

Science.gov (United States)

Hearn, Mark

2009-01-01

Color-blind racism develops when persons ignore color in people and see them simply as individuals. As persons of color in racialized societies such as the United States are unequally treated on account of their color, the issue becomes a matter of faith and religious experience as religious leaders and educators, who disregard color, overlook…

Experimental investigations on fiber laser color marking of steels

Energy Technology Data Exchange (ETDEWEB)

Amara, E.H., E-mail: amara@cdta.dz; Haïd, F.; Noukaz, A.

2015-10-01

Highlights: • We develop an experimental approach with the aim to bring a contribution to the comprehension of the occurring phenomena during laser color marking of steels. • We have used a home-made marking device composed of a pulsed fiber laser and galvanometric mirrors. • Both commercial and elaborated in laboratory steels have been used as samples. • The experiments have been performed for different laser beam operating parameters, under normal atmospheric conditions. • The treated samples were analyzed either by optical and scanning electronic microscopy, as well as by energy dispersion spectroscopy. - Abstract: We develop an experimental approach with the aim to bring a contribution to the comprehension of the occurring phenomena during laser color marking of steels. A home-made marking device using a pulsed fiber laser has been used to treat steel samples under different laser beam operating parameters, for different compositions of the processed steel, and at normal atmospheric conditions. The treated samples were analyzed either by optical and scanning electronic microscopy, as well as by energy dispersion spectroscopy. The results show the influence of the operating parameters on the obtained colors.

Experimental investigations on fiber laser color marking of steels

International Nuclear Information System (INIS)

Amara, E.H.; Haïd, F.; Noukaz, A.

2015-01-01

Highlights: • We develop an experimental approach with the aim to bring a contribution to the comprehension of the occurring phenomena during laser color marking of steels. • We have used a home-made marking device composed of a pulsed fiber laser and galvanometric mirrors. • Both commercial and elaborated in laboratory steels have been used as samples. • The experiments have been performed for different laser beam operating parameters, under normal atmospheric conditions. • The treated samples were analyzed either by optical and scanning electronic microscopy, as well as by energy dispersion spectroscopy. - Abstract: We develop an experimental approach with the aim to bring a contribution to the comprehension of the occurring phenomena during laser color marking of steels. A home-made marking device using a pulsed fiber laser has been used to treat steel samples under different laser beam operating parameters, for different compositions of the processed steel, and at normal atmospheric conditions. The treated samples were analyzed either by optical and scanning electronic microscopy, as well as by energy dispersion spectroscopy. The results show the influence of the operating parameters on the obtained colors

[Experiment studies of electron-positron interactions at the Stanford Linear Accelerator Center

International Nuclear Information System (INIS)

Hertzbach, S.S.; Kofler, R.R.

1993-01-01

The High Energy Physics group at the University of Massachusetts has continued its' program of experimental studies of electron-positron interactions at the Stanford Linear Accelerator Center (SLAC). The group activities have included: analysis of data taken between 1982 and 1990 with the TPC detector at the PEP facility, continuing data collection and data analysis using the SLC/SLD facility, planning for the newly approved B-factory at SLAC, and participation in design studies for future high energy linear colliders. This report will briefly summarize these activities

Coloration and bleaching mechanism of niobium oxide electrochromic thin films; Sanka niobu electromic usumaku no chakushoshoku mechanism

Energy Technology Data Exchange (ETDEWEB)

Yoshimura, K; Miki, T; Tazawa, M; Jin, P; Igarashi, K; Tanemura, S [National Industrial Research Institute of Nagoya, Nagoya (Japan)

1997-11-25

In order to search for the coloration and bleaching mechanism of niobium oxide, considerations were given on optical properties and electron conditions in niobium oxide thin films (glass plates as substrates coated with ITO) prepared by using the reactive DC magnetron sputtering process. The films were so grown that their thickness will all be 100 nm to facilitate data comparison. Coloration and bleaching of the grown test films were conducted by cyclic voltammetry. Electron spectra were measured by using XPS, and electron energy was analyzed. Coloration of niobium oxide occurs as a result of change in valency electron state from an Nb {sup 5+} state to an Nb {sup 4+} state, while change in the XPS spectra also corresponds with the above change. However, the XPS spectra differ greatly between crystalline samples and amorphous samples. The coloration and bleaching mechanism of the crystallized Nb2O5 film can be explained by a reaction formula similar to that for WO3. However, with regard to the amorphous Nb2O5 film, an independent reaction involving water in the film seems to occur together with the same reaction as in the crystallized film. 9 refs., 5 figs.

Experimental Study on Color Durability of Color Asphalt Pavement

Science.gov (United States)

Ning, Shi; Huan, Su

2017-06-01

Aiming at the poor Color durability and the lack of research on Color asphalt pavement, spraying an anti-tire trace seal resin emulsion on the surface, a Color durable asphalt pavement was proposed. After long-term rolling and long-term aging test, the Color durability was evaluated by RGB function in Photoshop and trace residue rate formula. Test results proved that the Evaluation method was simple and effective. After long-term rolling, the Color of the road surface tends to a constant value. Spraying the emulsion on the road surface can resist tire traces. After long-term aging test, the resistance to tire traces was increased by 26.6% compared with the conventional type, while the former was 44.1% higher than the latter without long-term aging. The Color durable asphalt pavement can effectively improve the ability of Color asphalt pavement to resist tire traces, and significantly improve the Color durability of Color asphalt pavement.

Japan Link Center (JaLC): link management and DOI assignment for Japanese electronic scholarly contents

Science.gov (United States)

Kato, Takafumi; Tsuchiya, Eri; Kubota, Soichi; Miyagawa, Yoshiyuki

JST, cooperated with several national institutes, is currently developing “Japan Link Center”, which manages Japanese electronic scholarly contents (journal articles, books, dissertations etc.) in an integrated fashion using Digital Object Identifier (DOI). Japan Link Center will manage metadata and whereabouts information of the contents in the digital environment and provide domestic and international linking information, cite/cited information to activate dissemination of S&T information, furthermore, to strengthen transmission of S&T information from Japan. Japan Link Center is expected to be appointed as the 9th DOI registration agency (RA) in the world by the International DOI Foundation (IDF) this spring.

Electron spin resonance characterization of trapping centers in Unibond reg-sign buried oxides

International Nuclear Information System (INIS)

Conley, J.F. Jr.; Lenahan, P.M.; Wallace, B.D.

1996-01-01

Electron spin resonance and capacitance vs. voltage measurements are used to evaluate the radiation response of Unibond buried oxides. When damaged by hole injection, it is found that Unibond reg-sign buried oxides exhibit a rough correspondence between E' centers and positive charge as well as generation of P b centers at the Unibond buried oxide/Si interface. In these respects, Unibond buried oxides qualitatively resemble thermal SiO 2 . However, a hydrogen complexed E' center known as the 74 G doublet is also detected in the Unibond buried oxides. This defect is not detectable in thermal SiO 2 under similar circumstances. Since the presence of 74 G doublet center is generally indicative of very high hydrogen content and since hydrogen is clearly a significant participant in radiation damage, this result suggests a qualitative difference between the radiation response of Unibond and thermal SiO 2 . Unibond results are also compared and contrasted with similar investigations on separation-by-implanted-oxygen (SIMOX) buried oxides. Although the charge trapping response of Unibond buried oxides may be inferior to that of radiation hardened thermal SiO 2 , it appears to be more simple and superior to that of SIMOX buried oxides

Continuous wave protocol for simultaneous polarization and optical detection of P1-center electron spin resonance

Science.gov (United States)

Kamp, E. J.; Carvajal, B.; Samarth, N.

2018-01-01

The ready optical detection and manipulation of bright nitrogen vacancy center spins in diamond plays a key role in contemporary quantum information science and quantum metrology. Other optically dark defects such as substitutional nitrogen atoms (`P1 centers') could also become potentially useful in this context if they could be as easily optically detected and manipulated. We develop a relatively straightforward continuous wave protocol that takes advantage of the dipolar coupling between nitrogen vacancy and P1 centers in type 1b diamond to detect and polarize the dark P1 spins. By combining mutual spin flip transitions with radio frequency driving, we demonstrate the simultaneous optical polarization and detection of the electron spin resonance of the P1 center. This technique should be applicable to detecting and manipulating a broad range of dark spin populations that couple to the nitrogen vacancy center via dipolar fields, allowing for quantum metrology using these spin populations.

TRANSIENT ELECTRONICS CATEGORIZATION

Science.gov (United States)

2017-08-24

AFRL-RY-WP-TR-2017-0169 TRANSIENT ELECTRONICS CATEGORIZATION Dr. Burhan Bayraktaroglu Devices for Sensing Branch Aerospace Components & Subsystems...SUBTITLE TRANSIENT ELECTRONICS CATEGORIZATION 5a. CONTRACT NUMBER In-house 5b. GRANT NUMBER N/A 5c. PROGRAM ELEMENT NUMBER N/A 6. AUTHOR(S) Dr. Burhan...88ABW-2017-3747, Clearance Date 31 July 2017. Paper contains color. 14. ABSTRACT Transient electronics is an emerging technology area that lacks proper

Tree Colors: Color Schemes for Tree-Structured Data.

Science.gov (United States)

Tennekes, Martijn; de Jonge, Edwin

2014-12-01

We present a method to map tree structures to colors from the Hue-Chroma-Luminance color model, which is known for its well balanced perceptual properties. The Tree Colors method can be tuned with several parameters, whose effect on the resulting color schemes is discussed in detail. We provide a free and open source implementation with sensible parameter defaults. Categorical data are very common in statistical graphics, and often these categories form a classification tree. We evaluate applying Tree Colors to tree structured data with a survey on a large group of users from a national statistical institute. Our user study suggests that Tree Colors are useful, not only for improving node-link diagrams, but also for unveiling tree structure in non-hierarchical visualizations.

Illuminant color estimation based on pigmentation separation from human skin color

Science.gov (United States)

Tanaka, Satomi; Kakinuma, Akihiro; Kamijo, Naohiro; Takahashi, Hiroshi; Tsumura, Norimichi

2015-03-01

Human has the visual system called "color constancy" that maintains the perceptive colors of same object across various light sources. The effective method of color constancy algorithm was proposed to use the human facial color in a digital color image, however, this method has wrong estimation results by the difference of individual facial colors. In this paper, we present the novel color constancy algorithm based on skin color analysis. The skin color analysis is the method to separate the skin color into the components of melanin, hemoglobin and shading. We use the stationary property of Japanese facial color, and this property is calculated from the components of melanin and hemoglobin. As a result, we achieve to propose the method to use subject's facial color in image and not depend on the individual difference among Japanese facial color.

Intense source of spin-polarized electrons using laser-induced optical pumping

International Nuclear Information System (INIS)

Gray, L.G.; Giberson, K.W.; Cheng, C.; Keiffer, R.S.; Dunning, F.B.; Walters, G.K.

1983-01-01

A source of spin-polarized electrons based on a laser-pumped flowing helium afterglow is described. He(2 3 S) atoms contained in the afterglow are optically pumped using circularly polarized 1.08-μm (2 3 S→2 3 P) radiation provided by a NaF (F 2+ )( color-center laser. Spin angular momentum conservation in subsequent chemi-ionization reactions with CO 2 produces polarized electrons that are extracted from the afterglow. At low currents, < or approx. =1 μA, polarizations of approx.70%--80% are achieved. At higher currents the polarization decreases, falling to approx.40% at 50 μA. The spin polarization can be simply reversed (P→-P) and the source is suitable for use in the majority of low-energy spin-dependent scattering experiments proposed to date

Assessment of NPP VIIRS Ocean Color Data Products: Hope and Risk

Science.gov (United States)

Turpie, Kevin R.; Meister, Gerhard; Eplee, Gene; Barnes, Robert A.; Franz, Bryan; Patt, Frederick S.; Robinson, Wayne d.; McClain, Charles R.

2010-01-01

For several years, the NASA/Goddard Space Flight Center (GSFC) NPP VIIRS Ocean Science Team (VOST) provided substantial scientific input to the NPP project regarding the use of Visible Infrared Imaging Radiometer Suite (VIIRS) to create science quality ocean color data products. This work has culminated into an assessment of the NPP project and the VIIRS instrument's capability to produce science quality Ocean Color data products. The VOST concluded that many characteristics were similar to earlier instruments, including SeaWiFS or MODIS Aqua. Though instrument performance and calibration risks do exist, it was concluded that programmatic and algorithm issues dominate concerns. Keywords: NPP, VIIRS, Ocean Color, satellite remote sensing, climate data record.

INFRARED COLOR-COLOR DIAGRAMS FOR AGB STARS

Directory of Open Access Journals (Sweden)

Kyung-Won Suh

2007-09-01

Full Text Available We present infrared color-color diagrams of AGB stars from the observations at near and mid infrared bands. We compile the observations for hundreds of OH/IR stars and carbon stars using the data from the Midcourse Space Experiment (MSX, the two micron sky survey (2MASS, and the IRAS point source catalog (PSC. We compare the observations with the theoretical evolutionary tracks of AGB stars. From the new observational data base and the theoretical evolution tracks, we discuss the meaning of the infrared color-color diagrams at different wavelengths.

Color digital halftoning taking colorimetric color reproduction into account

Science.gov (United States)

Haneishi, Hideaki; Suzuki, Toshiaki; Shimoyama, Nobukatsu; Miyake, Yoichi

1996-01-01

Taking colorimetric color reproduction into account, the conventional error diffusion method is modified for color digital half-toning. Assuming that the input to a bilevel color printer is given in CIE-XYZ tristimulus values or CIE-LAB values instead of the more conventional RGB or YMC values, two modified versions based on vector operation in (1) the XYZ color space and (2) the LAB color space were tested. Experimental results show that the modified methods, especially the method using the LAB color space, resulted in better color reproduction performance than the conventional methods. Spatial artifacts that appear in the modified methods are presented and analyzed. It is also shown that the modified method (2) with a thresholding technique achieves a good spatial image quality.

Color preferences change after experience with liked/disliked colored objects.

Science.gov (United States)

Strauss, Eli D; Schloss, Karen B; Palmer, Stephen E

2013-10-01

How are color preferences formed, and can they be changed by affective experiences with correspondingly colored objects? We examined these questions by testing whether affectively polarized experiences with images of colored objects would cause changes in color preferences. Such changes are implied by the ecological valence theory (EVT), which posits that color preferences are determined by people's average affective responses to correspondingly colored objects (Palmer & Schloss, Proceedings of the National Academy of Sciences, 107, 8877-8882, 2010). Seeing images of strongly liked (and disliked) red and green objects, therefore, should lead to increased (and decreased) preferences for correspondingly colored red and green color patches. Experiment 1 showed that this crossover interaction did occur, but only if participants were required to evaluate their preferences for the colored objects when they saw them. Experiment 2 showed that these overall changes decreased substantially over a 24-h delay, but the degree to which the effect lasted for individuals covaried with the magnitude of the effects immediately after object exposure. Experiment 3 demonstrated a similar, but weaker, effect of affectively biased changes in color preferences when participants did not see, but only imagined, the colored objects. The overall pattern of results indicated that color preferences are not fixed, but rather are shaped by affective experiences with colored objects. Possible explanations for the observed changes in color preferences were considered in terms of associative learning through evaluative conditioning and/or priming of prior knowledge in memory.

Influence of color word availability on the Stroop color-naming effect.

Science.gov (United States)

Kim, Hyosun; Cho, Yang Seok; Yamaguchi, Motonori; Proctor, Robert W

2008-11-01

Three experiments tested whether the Stroop color-naming effect is a consequence of word recognition's being automatic or of the color word's capturing visual attention. In Experiment 1, a color bar was presented at fixation as the color carrier, with color and neutral words presented in locations above or below the color bar; Experiment 2 was similar, except that the color carrier could occur in one of the peripheral locations and the color word at fixation. The Stroop effect increased as display duration increased, and the Stroop dilution effect (a reduced Stroop effect when a neutral word is also present) was an approximately constant proportion of the Stroop effect at all display durations, regardless of whether the color bar or color word was at fixation. In Experiment 3, the interval between the onsets of the to-be-named color and the color word was manipulated. The Stroop effect decreased with increasing delay of the color word onset, but the absolute amount of Stroop dilution produced by the neutral word increased. This study's results imply that an attention shift from the color carrier to the color word is an important factor modulating the size of the Stroop effect.

Representing Color Ensembles.

Science.gov (United States)

Chetverikov, Andrey; Campana, Gianluca; Kristjánsson, Árni

2017-10-01

Colors are rarely uniform, yet little is known about how people represent color distributions. We introduce a new method for studying color ensembles based on intertrial learning in visual search. Participants looked for an oddly colored diamond among diamonds with colors taken from either uniform or Gaussian color distributions. On test trials, the targets had various distances in feature space from the mean of the preceding distractor color distribution. Targets on test trials therefore served as probes into probabilistic representations of distractor colors. Test-trial response times revealed a striking similarity between the physical distribution of colors and their internal representations. The results demonstrate that the visual system represents color ensembles in a more detailed way than previously thought, coding not only mean and variance but, most surprisingly, the actual shape (uniform or Gaussian) of the distribution of colors in the environment.

Luminance contours can gate afterimage colors and 'real' colors

NARCIS (Netherlands)

Anstis, S.; Vergeer, M.L.T.; Lier, R.J. van

2012-01-01

It has long been known that colored images may elicit afterimages in complementary colors. We have already shown (Van Lier, Vergeer, & Anstis, 2009) that one and the same adapting image may result in different afterimage colors, depending on the test contours presented after the colored image. The

Digital color imaging

CERN Document Server

Fernandez-Maloigne, Christine; Macaire, Ludovic

2013-01-01

This collective work identifies the latest developments in the field of the automatic processing and analysis of digital color images.For researchers and students, it represents a critical state of the art on the scientific issues raised by the various steps constituting the chain of color image processing.It covers a wide range of topics related to computational color imaging, including color filtering and segmentation, color texture characterization, color invariant for object recognition, color and motion analysis, as well as color image and video indexing and retrieval. <

Color-quality control using color-difference formulas: progress and problems

Science.gov (United States)

Melgosa, M.; Gómez-Robledo, L.; García, P. A.; Morillas, S.; Fernández-Maloigne, C.; Richard, N.; Huang, M.; Li, C.; Cui, G.

2017-08-01

We report on some recent advances in industrial color-difference evaluation focused in three main fields: Development of reliable experimental visual datasets; proposal of new color spaces and color-difference formulas; tools to evaluate the merits of color-difference formulas. The use of fuzzy techniques to assign consistency degrees to color pairs in combined visual datasets is described. The CIE/ISO joint proposal of the CIEDE2000 color-difference formula as a standard will facilitate the communication among companies and users. The CIE recommendation of the STRESS index to assess observers' variability and relative merits of different color-difference formulas is reported. Power functions are an efficient method to improve the performance of modern color-difference formulas. We need of advanced color-difference formulas accounting for new materials with different kind of textures and gonioapparent effects.

Characterization of Angle Dependent Color Travel of Printed Multi-Color Effect Pigment on Different Color Substrates

Directory of Open Access Journals (Sweden)

Mirica Karlovits

2015-03-01

Full Text Available Color-travel pigments, which exhibit much more extensive color change as well provide angle-dependent optical effect can be used in many industrial products. In present paper the multi-color effect pigment printed on three different foils with different background color (black, silver and transparent was investigated. The pigment was based on synthetically produced transparent silicon dioxide platelets coated with titanium dioxide. CIEL*a*b* values and reflection of prints were measured by multi-angle spectrophotometer at constant illumination at an angle of 45º and different viewing angles (-15º, 15°, 25º, 45º, 75º and 110º were used. The measurements of printed multi-color pigment showed that CIEL*a*b* color coordinates varied to great extents, depending on detection angles as well on color of the printing substrate. The study revealed that pigmnet printed on black background obtained significant change in color. The study has also shown that when viewing angle increases, the reflection curves decreases.

Online Canton Fairs Ready for Convenient Trade--An Interview with Ding Qiang, General Manager of MOFCOM China International Electronic Commerce Center

Institute of Scientific and Technical Information of China (English)

Li Yinghong; Sun Yongjian

2006-01-01

@@ In 2006, the Canton Fairs will greet the 99th and 100th respectively in spring and fall. To meet the need of the development of the convenient trade, the Canton Fairs website, the platform of the online Canton Fairs run by MOFCOM China International Electronic Commerce Center is ready to take several effective measures to offer more convenient services. On March 24, China's Foreign Trade took the occasion to interview with Mr. Ding Qiang, General Manager of MOFCOM China International Electronic Commerce Center.

A new pathway for transmembrane electron transfer in photosynthetic reaction centers of Rhodobacter sphaeroides not involving the excited special pair.

NARCIS (Netherlands)

van Brederode, M.E.; Jones, M.R.; van Mourik, F.; van Stokkum, I.H.M.; van Grondelle, R.

1997-01-01

It is generally accepted that electron transfer in bacterial photosynthesis is driven by the first singlet excited state of a special pair of bacteriochlorophylls (P*). We have examined the first steps of electron transfer in a mutant of the Rhodobacter sphaeroides reaction center in which charge

A new pathway for transmembrane electron transfer in photosyntetic reaction centers of Rhodobacter sphaeroides not involving the excited special pair.

NARCIS (Netherlands)

van Brederode, M.E.; Jones, M.R.; van Mourik, F.; van Stokkum, I.H.M.; van Grondelle, R.

1997-01-01

It is generally accepted that electron transfer in bacterial photosynthesis is driven by the first singlet excited state of a special pair of bacteriochlorophylls (P*). We have examined the first steps of electron transfer in a mutant of the Rhodobacter sphaeroides reaction center in which charge

COLOR IMAGES

Directory of Open Access Journals (Sweden)

Dominique Lafon

2011-05-01

Full Text Available The goal of this article is to present specific capabilities and limitations of the use of color digital images in a characterization process. The whole process is investigated, from the acquisition of digital color images to the analysis of the information relevant to various applications in the field of material characterization. A digital color image can be considered as a matrix of pixels with values expressed in a vector-space (commonly 3 dimensional space whose specificity, compared to grey-scale images, is to ensure a coding and a representation of the output image (visualisation printing that fits the human visual reality. In a characterization process, it is interesting to regard color image attnbutes as a set of visual aspect measurements on a material surface. Color measurement systems (spectrocolorimeters, colorimeters and radiometers and cameras use the same type of light detectors: most of them use Charge Coupled Devices sensors. The difference between the two types of color data acquisition systems is that color measurement systems provide a global information of the observed surface (average aspect of the surface: the color texture is not taken into account. Thus, it seems interesting to use imaging systems as measuring instruments for the quantitative characterization of the color texture.

Examination of Color-Lighting Control System Using Colored Paper User Interface

Directory of Open Access Journals (Sweden)

Aida Hiroto

2016-01-01

Full Text Available In recent year, Full-Color LED Lighting that can be changed to various color such as red, green, blue has been appeared with development of LED Lighting. By Color-Lighting control, users affected such as concentrating and relaxing. Therefore, Color-lighting control will spread to various place such as home, offices, stations. However color-lighting control affected some disturbance such as daylight, display when Full-Color LED controlled indoors. Also, information devices control get difficult with information technology develop. I propose Color-Lighting Control System using Colored Paper User Interface(CLC/CPUI. The purpose of CLC/CPUI is that anyone can intuitively control Full-Color LED Lighting. CLC/CPUI uses colored paper as user interface by sensing the paper. CLC/CPUI realizes lighting color that user demanded to do feedback control. I conduct accuracy verification experiment of CLC/CPUI.

Colored Chaos

Science.gov (United States)

2004-01-01

[figure removed for brevity, see original site] Released 7 May 2004 This daytime visible color image was collected on May 30, 2002 during the Southern Fall season in Atlantis Chaos. The THEMIS VIS camera is capable of capturing color images of the martian surface using its five different color filters. In this mode of operation, the spatial resolution and coverage of the image must be reduced to accommodate the additional data volume produced from the use of multiple filters. To make a color image, three of the five filter images (each in grayscale) are selected. Each is contrast enhanced and then converted to a red, green, or blue intensity image. These three images are then combined to produce a full color, single image. Because the THEMIS color filters don't span the full range of colors seen by the human eye, a color THEMIS image does not represent true color. Also, because each single-filter image is contrast enhanced before inclusion in the three-color image, the apparent color variation of the scene is exaggerated. Nevertheless, the color variation that does appear is representative of some change in color, however subtle, in the actual scene. Note that the long edges of THEMIS color images typically contain color artifacts that do not represent surface variation. Image information: VIS instrument. Latitude -34.5, Longitude 183.6 East (176.4 West). 38 meter/pixel resolution. Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time. NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D

Color vision test

Science.gov (United States)

... present from birth) color vision problems: Achromatopsia -- complete color blindness , seeing only shades of gray Deuteranopia -- difficulty telling ... Vision test - color; Ishihara color vision test Images Color blindness tests References Bowling B. Hereditary fundus dystrophies. In: ...

S3-3: Misbinding of Color and Motion in Human V2 Revealed by Color-Contingent Motion Adaptation

Directory of Open Access Journals (Sweden)

Fang Fang

2012-10-01

Full Text Available Wu, Kanai, & Shimojo (2004 Nature 429 262 described a compelling illusion demonstrating a steady-state misbinding of color and motion. Here, we took advantage of the illusion and performed psychophysical and fMRI adaptation experiments to explore the neural mechanism of color-motion misbinding. The stimulus subtended 20 deg by 14 deg of visual angle and contained two sheets of random dots, one sheet moving up and the other moving down. On the upward-moving sheet, dots in the right-end area (4 deg by 14 deg were red, and the rest of the dots were green. On the downward-moving sheet, dots in the right-end area were green, and the rest of the dots were red. When subjects fixated at the center of the stimulus, they bound the color and motion of the dots in the right-end area erroneously–the red dots appeared to move downwards and the green dots appeared to move upwards. In the psychophysical experiment, we measured the color-contingent motion aftereffect in the right-end area after adaptation to the illusory stimulus. A significant aftereffect was observed as if subjects had adapted to the perceived binding of color and motion, rather than the physical binding. For example, after adaptation, stationary red dots appeared to move upwards, and stationary green dots appeared to move downwards. In the fMRI experiment, we measured direction-selective motion adaptation effects in V1, V2, V3, V4, V3A/B, and V5. Relative to other cortical areas, V2 showed a much stronger adaptation effect to the perceived motion direction (rather than the physical direction for both the red and green dots. Significantly, the fMRI adaptation effect in V2 correlated with the color-contingent motion aftereffect across twelve subjects. This study provides the first human evidence that color and motion could be misbound at a very early stage of visual processing.

Lithographically-generated 3D lamella layers and their structural color

Science.gov (United States)

Zhang, Sichao; Chen, Yifang; Lu, Bingrui; Liu, Jianpeng; Shao, Jinhai; Xu, Chen

2016-04-01

Inspired by the structural color from the multilayer nanophotonic structures in Morpho butterfly wing scales, 3D lamellae layers in dielectric polymers (polymethyl methacrylate, PMMA) with n ~ 1.5 were designed and fabricated by standard top-down electron beam lithography with one-step exposure followed by an alternating development/dissolution process of PMMA/LOR (lift-off resist) multilayers. This work offers direct proof of the structural blue/green color via lithographically-replicated PMMA/air multilayers, analogous to those in real Morpho butterfly wings. The success of nanolithography in this work for the 3D lamellae structures in dielectric polymers not only enables us to gain deeper insight into the mysterious blue color of the Morpho butterfly wings, but also breaks through the bottleneck in technical development toward broad applications in gas/liquid sensors, 3D meta-materials, coloring media, and infrared imaging devices, etc.

Colors, colored overlays, and reading skills

OpenAIRE

Uccula, Arcangelo; Enna, Mauro; Mulatti, Claudio

2014-01-01

In this article, we are concerned with the role of colors in reading written texts. It has been argued that colored overlays applied above written texts positively influence both reading fluency and reading speed. These effects would be particularly evident for those individuals affected by the so called Meares-Irlen syndrome, i.e., who experience eyestrain and/or visual distortions – e.g., color, shape, or movement illusions – while reading. This condition would interest the 12–14% of the ge...

Space Environmental Effects on Colored Coatings and Anodizes

Science.gov (United States)

Kamenetzky, Rachel R.; Finckenor, Miria M.; Vaughn, Jason A.

1999-01-01

Colored coatings and anodizes are used on spacecraft as markers and astronaut visual aids. These materials must be stable in the space environment and withstand atomic oxygen, ultraviolet radiation, particulate radiation, thermal cycling, and high vacuum without significant change in optical and mechanical properties. A variety of colored coatings and anodizes have been exposed to simulated space environments at Marshall Space Flight Center and also actual space environment as part of the Passive Optical Sample Assembly (POSA) - I flight experiment. Colored coatings were developed by AZ Technology, Huntsville, AL, under a NASA contract for International Space Station (ISS). These include yellow, red, blue, and black paints suitable for Extra-Vehicular Activity (EVA) visual aids and ISS emblems. AaChron, Inc., Minneapolis, MN, developed stable colored anodizes, also in yellow, red, blue, and black, for astronaut visual aids. These coatings were exposed in the laboratory to approximately 550 equivalent sun-hours of solar ultraviolet radiation and approximately 1 x 10(exp 21) atoms/sq cm of atomic oxygen in vacuum. The AZ Technology yellow colored coating, designated TMS800IY, and all four AaChron colored anodizes were flown on POSA-I. POSA-I was a Risk Mitigation Experiment for ISS. It was attached to the exterior of the Mir space station docking module by EVA and was exposed for 18 months. The laboratory-simulated space environment, the natural space environment and the unique environment of an orbiting, active space station and their effects on these developmental materials are discussed.

Structural colors from Morpho peleides butterfly wing scales

KAUST Repository

Ding, Yong; Xu, Sheng; Wang, Zhong Lin

2009-01-01

A male Morpho peleides butterfly wing is decorated by two types of scales, cover and ground scales. We have studied the optical properties of each type of scales in conjunction with the structural information provided by cross-sectional transmission electron microscopy and computer simulation. The shining blue color is mainly from the Bragg reflection of the one-dimensional photonic structure, e.g., the shelf structure packed regularly in each ridges on cover scales. A thin-film-like interference effect from the base plate of the cover scale enhances such blue color and further gives extra reflection peaks in the infrared and ultraviolet regions. The analogy in the spectra acquired from the original wing and that from the cover scales suggests that the cover scales take a dominant role in its structural color. This study provides insight of using the biotemplates for fabricating smart photonic structures. © 2009 American Institute of Physics.

Color Appearance of the Neon Color Spreading Effect

Directory of Open Access Journals (Sweden)

Damir Vusić

2017-04-01

Full Text Available As a part of this paper, the influence of various parameters within the target process of graphic reproduction on the color appearance of the neon color spreading effect was investigated. The shift in a color appearance qualitatively is determined through the calculation of changes in perceptual attributes of color, i.e. differences in lightness, chroma and hue. The influence of different media (printed images, and LCD display in the “cross-media” system was examined, as well as the role of the inserted segment color choice and background of the primary stimulus as an element of design solutions. These parameters were evaluated in a variety of ambient conditions and under the observation of three CIE standard light sources and illuminants. It was found that it was mostly the changes of the chroma and lightness. The change in the color hue is the lowest.

Using Single Colors and Color Pairs to Communicate Basic Tastes

Directory of Open Access Journals (Sweden)

Andy T. Woods

2016-07-01

Full Text Available Recently, it has been demonstrated that people associate each of the basic tastes (e.g., sweet, sour, bitter, and salty with specific colors (e.g., red, green, black, and white. In the present study, we investigated whether pairs of colors (both associated with a particular taste or taste word would give rise to stronger associations relative to pairs of colors that were associated with different tastes. We replicate the findings of previous studies highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. However, while there was evidence that pairs of colors could indeed communicate taste information more consistently than single colors, our participants took more than twice as long to match the color pairs with tastes than the single colors. Possible reasons for these results are discussed.

Using Single Colors and Color Pairs to Communicate Basic Tastes.

Science.gov (United States)

Woods, Andy T; Spence, Charles

2016-01-01

Recently, it has been demonstrated that people associate each of the basic tastes (e.g., sweet, sour, bitter, and salty) with specific colors (e.g., red, green, black, and white). In the present study, we investigated whether pairs of colors (both associated with a particular taste or taste word) would give rise to stronger associations relative to pairs of colors that were associated with different tastes. We replicate the findings of previous studies highlighting the existence of a robust crossmodal correspondence between individual colors and basic tastes. However, while there was evidence that pairs of colors could indeed communicate taste information more consistently than single colors, our participants took more than twice as long to match the color pairs with tastes than the single colors. Possible reasons for these results are discussed.

Center for electron nanoscopy, DTU

DEFF Research Database (Denmark)

Horsewell, Andy; Somers, Marcel A. J.; Chorkendorff, Ib

2006-01-01

front is in the field of scanning electron microscopy, SEM, which has already seen major advances due to field emission electron guns, FEG: I) Adding a focussed ion beam, so that specimen surface layers can be removed by controlled sputtering, a dual-beam FEGSEM FIB allows reconstruction...... image reconstruction from multiple images acquired through 70o tilts, TEM tomography can map nanostructures in 3D; III) Observation of TEM specimens in an environmental cell, at temperature and in a controlled gaseous environment, can provide in-situ observations of gas-solid interactions. The second...

The interaction between surface color and color knowledge: behavioral and electrophysiological evidence.

Science.gov (United States)

Bramão, Inês; Faísca, Luís; Forkstam, Christian; Inácio, Filomena; Araújo, Susana; Petersson, Karl Magnus; Reis, Alexandra

2012-02-01

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 object were presented. Continuous electroencephalogram was recorded from 26 subjects. A cluster randomization procedure was used to explore the differences between typical and atypical color objects in each task. In the color knowledge task, we found two significant clusters that were consistent with the N350 and late positive complex (LPC) effects. Atypical color objects elicited more negative ERPs compared to typical color objects. The color effect found in the N350 time window suggests that surface color is an important cue that facilitates the selection of a stored object representation from long-term memory. Moreover, the observed LPC effect suggests that surface color activates associated semantic knowledge about the object, including color knowledge representations. We did not find any significant differences between typical and atypical color objects in the surface color verification task, which indicates that there is little contribution of color knowledge to resolve the surface color verification. Our main results suggest that surface color is an important visual cue that triggers color knowledge, thereby facilitating object identification. Copyright © 2011 Elsevier Inc. All rights reserved.

Color-Blindness Study: Color Discrimination on the TICCIT System.

Science.gov (United States)

Asay, Calvin S.; Schneider, Edward W.

The question studied whether the specific seven TICCIT system colors used within color coding schemes can be a source of confusion, or not seen at all, by the color-blind segment of target populations. Subjects were 11 color-blind and three normally sighted students at Brigham Young University. After a preliminary training exercise to acquaint the…

Human preferences for colorful birds: Vivid colors or pattern?

Science.gov (United States)

Lišková, Silvie; Landová, Eva; Frynta, Daniel

2015-04-29

In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern), and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.

Human Preferences for Colorful Birds: Vivid Colors or Pattern?

Directory of Open Access Journals (Sweden)

Silvie Lišková

2015-04-01

Full Text Available In a previous study, we found that the shape of a bird, rather than its color, plays a major role in the determination of human preferences. Thus, in the present study, we asked whether the preferences of human respondents towards uniformly shaped, colorful birds are determined by pattern rather than color. The experimental stimuli were pictures of small passerine birds of the family Pittidae possessing uniform shape but vivid coloration. We asked 200 participants to rank 43 colored and 43 identical, but grayscaled, pictures of birds. To find the traits determining human preferences, we performed GLM analysis in which we tried to explain the mean preference ranks and PC axes by the following explanatory variables: the overall lightness and saturation, edges (pattern, and the portion of each of the basic color hues. The results showed that the mean preference ranks of the grayscale set is explained mostly by the birds' pattern, whereas the colored set ranking is mostly determined by the overall lightness. The effect of colors was weaker, but still significant, and revealed that people liked blue and green birds. We found no significant role of the color red, the perception of which was acquired relatively recently in evolution.

Industrial Color Physics

CERN Document Server

Klein, Georg A

2010-01-01

This unique book starts with a short historical overview of the development of the theories of color vision and applications of industrial color physics. The three dominant factors producing color - light source, color sample, and observer - are described in detail. The standardized color spaces are shown and related color values are applied to characteristic color qualities of absorption as well as of effect colorants. The fundamentals of spectrometric and colorimetric measuring techniques together with specific applications are described. Theoretical models for radiative transfer in transparent, translucent, and opaque layers are detailed; the two, three, and multi-flux approximations are presented for the first time in a coherent formalism. These methods constitute the fundamentals not only for the important classical methods, but also modern methods of recipe prediction applicable to all known colorants. The text is supplied with 52 tables, more than 200 partially colored illustrations, an appendix, and a...

Photoluminescence of radiation-induced color centers in lithium fluoride thin films for advanced diagnostics of proton beams

Energy Technology Data Exchange (ETDEWEB)

Piccinini, M., E-mail: massimo.piccinini@enea.it; Ampollini, A.; Picardi, L.; Ronsivalle, C.; Bonfigli, F.; Libera, S.; Vincenti, M. A.; Montereali, R. M. [ENEA, C.R. Frascati, UTAPRAD, Technical Unit for Development and Applications of Radiations, Via E. Fermi 45, 00044 Frascati (Rome) (Italy); Ambrosini, F. [University Sapienza-Roma I, Piazzale Aldo Moro 5, 00185 Rome (Italy); Nichelatti, E. [ENEA, C.R. Casaccia, UTTMAT, Technical Unit for Materials Technologies, Via Anguillarese 301, 00123 S. Maria di Galeria (Rome) (Italy)

2015-06-29

Systematic irradiation of thermally evaporated 0.8 μm thick polycrystalline lithium fluoride films on glass was performed by proton beams of 3 and 7 MeV energies, produced by a linear accelerator, in a fluence range from 10{sup 11} to 10{sup 15} protons/cm{sup 2}. The visible photoluminescence spectra of radiation-induced F{sub 2} and F{sub 3}{sup +} laser active color centers, which possess almost overlapping absorption bands at about 450 nm, were measured under laser pumping at 458 nm. On the basis of simulations of the linear energy transfer with proton penetration depth in LiF, it was possible to obtain the behavior of the measured integrated photoluminescence intensity of proton irradiated LiF films as a function of the deposited dose. The photoluminescence signal is linearly dependent on the deposited dose in the interval from 10{sup 3} to about 10{sup 6 }Gy, independently from the used proton energies. This behavior is very encouraging for the development of advanced solid state radiation detectors based on optically transparent LiF thin films for proton beam diagnostics and two-dimensional dose mapping.

Color related to ceramic and zirconia restorations: a review.

Science.gov (United States)

Vichi, Alessandro; Louca, Chris; Corciolani, Gabriele; Ferrari, Marco

2011-01-01

The requirement to achieve natural looking restorations is one of the most challenging aspects of dentistry, and the shade matching of dental restorations with the natural dentition is a difficult task due to the complex optical characteristics of natural teeth. Dental porcelain is considered the reference material for prosthetic rehabilitation, but it is not easy to handle and aesthetic excellence is quite difficult to obtain. For these reasons, shade matching with dental porcelain is often considered to be more artistic than scientific. Shade matching is considered unpredictable due to several variables that may influence the final appearance of a restoration. In order to improve this situation, over the last decade new shade guides and instruments have been developed and the aesthetic aspects of dental porcelain have been further investigated. In this review some aspects of color selection and color reproduction have been examined. Color selection has advanced through the development of new shade guides and electronic shade taking devices, although visual assessment has still not been entirely replaced by electronic instruments. Color reproduction with dental porcelain has improved thanks to advances in the performance and knowledge of dental porcelain, but is still not easy to achieve. The difficulties of achieving good aesthetics with PFM restorations and the desire for metal free solutions have resulted in the increased use of zirconia. The unique optical properties of zirconia have introduced new opportunities for achieving superior aesthetics, however further research is required with this material. Copyright © 2010 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Color naming

OpenAIRE

Şahin, Ebru

1998-01-01

Ankara : Bilkent University, Department of Interior Architecture and Environmental Design and Institute of Fine Arts, 1998. Thesis (Ph.D) -- Bilkent University, 1998 Includes bibliographical refences. In this study, visual aspects of color and neurophysiological processes involved in the phenomenon, language of color and color models were explained in addition to the discussion of different ideas, orientations and previous works behind the subject of matter. Available color ...

Accurate color measurement methods for medical displays.

Science.gov (United States)

Saha, Anindita; Kelley, Edward F; Badano, Aldo

2010-01-01

The necessity for standard instrumentation and measurements of color that are repeatable and reproducible is the major motivation behind this work. Currently, different instrumentation and methods can yield very different results when measuring the same feature such as color uniformity or color difference. As color increasingly comes into play in medical imaging diagnostics, display color will have to be quantified in order to assess whether the display should be used for imaging purposes. The authors report on the characterization of three novel probes for measuring display color with minimal contamination from screen areas outside the measurement spot or from off-normal emissions. They compare three probe designs: A modified small-spot luminance probe and two conic probe designs based on black frusta. To compare the three color probe designs, spectral and luminance measurements were taken with specialized instrumentation to determine the luminance changes and color separation abilities of the probes. The probes were characterized with a scanning slit method, veiling glare, and a moving laser and LED arrangement. The scanning slit measurement was done using a black slit plate over a white line on an LCD monitor. The luminance was measured in 1 mm increments from the center of the slit to +/- 15 mm above and below the slit at different distances between the probe and the slit. The veiling glare setup consisted of measurements of the luminance of a black spot pattern with a white disk of radius of 100 mm as the black spot increases in 1 mm radius increments. The moving LED and laser method consisted of a red and green light orthogonal to the probe tip for the light to directly shine into the probe. The green light source was moved away from the red source in 1 cm increments to measure color stray-light contamination at different probe distances. The results of the color testing using the LED and laser methods suggest a better performance of one of the frusta probes

Fabrication of Ultra-thin Color Films with Highly Absorbing Media Using Oblique Angle Deposition.

Science.gov (United States)

Yoo, Young Jin; Lee, Gil Ju; Jang, Kyung-In; Song, Young Min

2017-08-29

Ultra-thin film structures have been studied extensively for use as optical coatings, but performance and fabrication challenges remain.  We present an advanced method for fabricating ultra-thin color films with improved characteristics. The proposed process addresses several fabrication issues, including large area processing. Specifically, the protocol describes a process for fabricating ultra-thin color films using an electron beam evaporator for oblique angle deposition of germanium (Ge) and gold (Au) on silicon (Si) substrates.  Film porosity produced by the oblique angle deposition induces color changes in the ultra-thin film. The degree of color change depends on factors such as deposition angle and film thickness. Fabricated samples of the ultra-thin color films showed improved color tunability and color purity. In addition, the measured reflectance of the fabricated samples was converted into chromatic values and analyzed in terms of color. Our ultra-thin film fabricating method is expected to be used for various ultra-thin film applications such as flexible color electrodes, thin film solar cells, and optical filters. Also, the process developed here for analyzing the color of the fabricated samples is broadly useful for studying various color structures.

Color response and color transport in a quark-gluon plasma

International Nuclear Information System (INIS)

Heinz, U.

1986-01-01

Using color kinetic theory, we discuss color conduction and color response in a quark-gluon plasma. Collective color oscillations and their damping rates are investigated. An instability of the thermal equilibrium state in high T QCD is discovered

Cognitive aspects of color

Science.gov (United States)

Derefeldt, Gunilla A. M.; Menu, Jean-Pierre; Swartling, Tiina

1995-04-01

This report surveys cognitive aspects of color in terms of behavioral, neuropsychological, and neurophysiological data. Color is usually defined as psychophysical color or as perceived color. Behavioral data on categorical color perception, absolute judgement of colors, color coding, visual search, and visual awareness refer to the more cognitive aspects of color. These are of major importance in visual synthesis and spatial organization, as already shown by the Gestalt psychologists. Neuropsychological and neurophysiological findings provide evidence for an interrelation between cognitive color and spatial organization. Color also enhances planning strategies, as has been shown by studies on color and eye movements. Memory colors and the color- language connections in the brain also belong among the cognitive aspects of color.

Color response and color transport in a quark-gluon plasma

International Nuclear Information System (INIS)

Heinz, U.

1986-01-01

Using color kinetic theory, the authors discuss color conduction and color response in a quark-gluon plasma. Collective color oscillations and their damping rates are investigated. An instability of the thermal equilibrium state in high T QCD is discovered

A Study of Color Transformation on Website Images for the Color Blind

OpenAIRE

Siew-Li Ching; Maziani Sabudin

2010-01-01

In this paper, we study on color transformation method on website images for the color blind. The most common category of color blindness is red-green color blindness which is viewed as beige color. By transforming the colors of the images, the color blind can improve their color visibility. They can have a better view when browsing through the websites. To transform colors on the website images, we study on two algorithms which are the conversion techniques from RGB colo...

Color reproduction system based on color appearance model and gamut mapping

Science.gov (United States)

Cheng, Fang-Hsuan; Yang, Chih-Yuan

2000-06-01

By the progress of computer, computer peripherals such as color monitor and printer are often used to generate color image. However, cross media color reproduction by human perception is usually different. Basically, the influence factors are device calibration and characterization, viewing condition, device gamut and human psychology. In this thesis, a color reproduction system based on color appearance model and gamut mapping is proposed. It consists of four parts; device characterization, color management technique, color appearance model and gamut mapping.

Color inference in visual communication: the meaning of colors in recycling.

Science.gov (United States)

Schloss, Karen B; Lessard, Laurent; Walmsley, Charlotte S; Foley, Kathleen

2018-01-01

People interpret abstract meanings from colors, which makes color a useful perceptual feature for visual communication. This process is complicated, however, because there is seldom a one-to-one correspondence between colors and meanings. One color can be associated with many different concepts (one-to-many mapping) and many colors can be associated with the same concept (many-to-one mapping). We propose that to interpret color-coding systems, people perform assignment inference to determine how colors map onto concepts. We studied assignment inference in the domain of recycling. Participants saw images of colored but unlabeled bins and were asked to indicate which bins they would use to discard different kinds of recyclables and trash. In Experiment 1, we tested two hypotheses for how people perform assignment inference. The local assignment hypothesis predicts that people simply match objects with their most strongly associated color. The global assignment hypothesis predicts that people also account for the association strengths between all other objects and colors within the scope of the color-coding system. Participants discarded objects in bins that optimized the color-object associations of the entire set, which is consistent with the global assignment hypothesis. This sometimes resulted in discarding objects in bins whose colors were weakly associated with the object, even when there was a stronger associated option available. In Experiment 2, we tested different methods for encoding color-coding systems and found that people were better at assignment inference when color sets simultaneously maximized the association strength between assigned color-object parings while minimizing associations between unassigned pairings. Our study provides an approach for designing intuitive color-coding systems that facilitate communication through visual media such as graphs, maps, signs, and artifacts.

A subjective evaluation of high-chroma color with wide color-gamut display

Science.gov (United States)

Kishimoto, Junko; Yamaguchi, Masahiro; Ohyama, Nagaaki

2009-01-01

Displays tends to expand its color gamut, such as multi-primary color display, Adobe RGB and so on. Therefore displays got possible to display high chroma colors. However sometimes, we feel unnatural some for the image which only expanded chroma. Appropriate gamut mapping method to expand color gamut is not proposed very much. We are attempting preferred expanded color reproduction on wide color gamut display utilizing high chroma colors effectively. As a first step, we have conducted an experiment to investigate the psychological effect of color schemes including highly saturated colors. We used the six-primary-color projector that we have developed for the presentation of test colors. The six-primary-color projector's gamut volume in CIELAB space is about 1.8 times larger than the normal RGB projector. We conducted a subjective evaluation experiment using the SD (Semantic Differential) technique to find the quantitative psychological effect of high chroma colors.

Role of color memory in successive color constancy.

Science.gov (United States)

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.

Correlation between grain orientation and the shade of color etching

International Nuclear Information System (INIS)

Szabo, Peter J.; Kardos, I.

2010-01-01

Color etching is an extremely effective metallographic technique not only for making grains well visible, but also for making them distinguishable for automated image analyzers. During color etching, a thin film is formed on the surface of the specimen. The thickness of this layer is in the order of magnitude of the visible light and since both the metal-film boundary and the film surface reflect light, an interference occurs. A wavelength-component of the white line is eliminated and its complementary color will be seen on the surface. As the thickness changes, the colors also change grain by grain. The thickness of the film is dependent on several factors, mostly on the type of the phase. However, different color shades can be observed on the surfaces of single phase materials, which phenomenon is caused by the different crystallographic orientations of the grains. This paper shows a combined color etching electron backscatter diffraction (EBSD) investigation of cast iron. An area of the surface of a gray cast iron specimen was etched. Colors were characterized by their luminescence and their red, green and blue intensity. An EBSD orientation map was taken from the same area and the orientations of the individual grains were determined. Results showed that a strong correlation was found between the luminescence and the R, G, B intensity of the color and the angle between the specimen normal and the direction, while such correlation was not observed between the color parameters and the and directions, respectively. This indicates that film thickness is sensitive to the direction of the crystal.

Inkjet printing the three organic functional layers of two-colored organic light emitting diodes

International Nuclear Information System (INIS)

Coenen, Michiel J.J.; Slaats, Thijs M.W.L.; Eggenhuisen, Tamara M.; Groen, Pim

2015-01-01

Inkjet printing allows for the roll-2-roll fabrication of organic electronic devices at an industrial scale. In this paper we demonstrate the fabrication of two-colored organic light emitting diodes (OLEDs) in which three adjacent organic device layers were inkjet printed from halogen free inks. The resulting devices demonstrate the possibilities offered by this technique for the fabrication of OLEDs for signage and personalized electronics. - Highlights: • Two-colored organic light emitting diodes with 3 inkjet printed device layers were fabricated. • All materials were printed from halogen free inks. • Inkjet printing of emissive materials is suitable for signage applications

Color stability of esthetic coatings applied to nickel-titanium archwires

Directory of Open Access Journals (Sweden)

Marcus Vinicius Neiva Nunes do REGO

Full Text Available Abstract Introduction Color stability is an important feature to be considered when using esthetic coated archwires. Objective To evaluate color changes on the surface of esthetic nickel-titanium archwires coated with Teflon (Ortho Organizers, USA or epoxy resin (Tecnident, Brazil after immersion in staining solution. Material and method Twelve 20-mm-long wire segments were used for each type of coating, which were mounted as two test specimens with a width of 7 mm each. The buccal surface of the archwires was evaluated for fluorescence and color measurements both at baseline and after immersion in a staining solution for 21 days using the VITA Easyshade® Compact spectrophotometer (Model DEASYC220. Differences in total color change according to coating type were compared using an independent samples t-test (p<0.05. The surface characteristics of as-received coated archwires were assessed using scanning electron microscopy. Result Color changes were observed on the esthetic coatings, with a significant difference between the two brands analyzed. Surface analysis revealed flaws such as wear, pitting, elevations, lack of material, granulation, grooves, cracks, and lack of standardization in the coating process in all as-received archwires, but flaws were less evident in epoxy-resin coatings. Conclusion The two esthetic coatings did not show color stability, but Teflon coatings showed a more intense color change than epoxy-resin coatings.

Charge dynamics in aluminum oxide thin film studied by ultrafast scanning electron microscopy.

Science.gov (United States)

Zani, Maurizio; Sala, Vittorio; Irde, Gabriele; Pietralunga, Silvia Maria; Manzoni, Cristian; Cerullo, Giulio; Lanzani, Guglielmo; Tagliaferri, Alberto

2018-04-01

The excitation dynamics of defects in insulators plays a central role in a variety of fields from Electronics and Photonics to Quantum computing. We report here a time-resolved measurement of electron dynamics in 100 nm film of aluminum oxide on silicon by Ultrafast Scanning Electron Microscopy (USEM). In our pump-probe setup, an UV femtosecond laser excitation pulse and a delayed picosecond electron probe pulse are spatially overlapped on the sample, triggering Secondary Electrons (SE) emission to the detector. The zero of the pump-probe delay and the time resolution were determined by measuring the dynamics of laser-induced SE contrast on silicon. We observed fast dynamics with components ranging from tens of picoseconds to few nanoseconds, that fits within the timescales typical of the UV color center evolution. The surface sensitivity of SE detection gives to the USEM the potential of applying pump-probe investigations to charge dynamics at surfaces and interfaces of current nano-devices. The present work demonstrates this approach on large gap insulator surfaces. Copyright © 2018 Elsevier B.V. All rights reserved.

ColorPhylo: A Color Code to Accurately Display Taxonomic Classifications.

Science.gov (United States)

Lespinats, Sylvain; Fertil, Bernard

2011-01-01

Color may be very useful to visualise complex data. As far as taxonomy is concerned, color may help observing various species' characteristics in correlation with classification. However, choosing the number of subclasses to display is often a complex task: on the one hand, assigning a limited number of colors to taxa of interest hides the structure imbedded in the subtrees of the taxonomy; on the other hand, differentiating a high number of taxa by giving them specific colors, without considering the underlying taxonomy, may lead to unreadable results since relationships between displayed taxa would not be supported by the color code. In the present paper, an automatic color coding scheme is proposed to visualise the levels of taxonomic relationships displayed as overlay on any kind of data plot. To achieve this goal, a dimensionality reduction method allows displaying taxonomic "distances" onto a Euclidean two-dimensional space. The resulting map is projected onto a 2D color space (the Hue, Saturation, Brightness colorimetric space with brightness set to 1). Proximity in the taxonomic classification corresponds to proximity on the map and is therefore materialised by color proximity. As a result, each species is related to a color code showing its position in the taxonomic tree. The so called ColorPhylo displays taxonomic relationships intuitively and can be combined with any biological result. A Matlab version of ColorPhylo is available at http://sy.lespi.free.fr/ColorPhylo-homepage.html. Meanwhile, an ad-hoc distance in case of taxonomy with unknown edge lengths is proposed.

Effects of irradiation on color and lipid oxidation of prosciutto

International Nuclear Information System (INIS)

Kong Qiulian; Qi Wenyuan; Yue Ling; Chen Zhijun; Bao Yingzi; Dai Xudong; Xu Yun

2012-01-01

This study dealt with the effect of irradiation on the color, irradiation odor and lipid oxidation of prosciutto crudo. The hams were irradiated by γ-ray and electronic beam (EB). Changes of color, irradiation odor, TBA value (TBARS), peroxide value (POV), carbonyl value and conjugated diene value were analyzed and compared with non-irradiated hams. Results showed that color index (a * ) of control, γ-ray irradiated and EB irradiated were 14.39, 9.45 and 11.71 respectively. The ratios of a * /b * were different with the type of rays. The ratio of a * /b * of EB irradiation was same with control, while that of γ-ray irradiation was decreased apparently. γ-ray irradiation had been shown to have apparently detrimental effect on the color and odor of hams, while EB irradiation had little detrimental effect. Irradiation increased POV and conjugated diene value, but the amounts of lipid oxidation products (TBARS, carbonyl value) were less than nonirradiated hams. (authors)

Optical absorption and electron spin resonance in natural, irradiated and heated spodumene

International Nuclear Information System (INIS)

Ito, A.S.; Isotani, S.

1983-09-01

Heat treatment and X and γ-Rays irradiation of lylac and colorless natural spodumene, LiAlSi 2 O 6 , have been studied. Irradiation produces a color change, from lylac or colorless to green. Irradiated samples heated at 200 0 C turn lylac and bleach at 400 0 C. Optical absorption spectra were decomposed into gaussian line shape bands and it is observed that green and lylac centers are simultaneously created by irradiation. These centers are independent from each other. Optical absorption, EPR and X-Ray fluorescence results show the spectra of impurities, responsible by the presence of the created centers and indicated Mn participation in the process of centers creation and destruction. Decay Kinetics of green and lylac centers have been studied and it is observed that simple Kinetic models do not apply to these cases. An empirical fit allowed the calculation of activation energies of the lylac and green centers decays. Discussions about the present results led us to propose a new model where the green and lylac centers are due to Mn 3+ ions in two different Al 3+ sites, whose absorption are intensified by the interaction with an electron trapped in a neighbour oxygen. (Author) [pt

Color Space and Its Divisions: Color Order from Antiquity to the Present

Science.gov (United States)

Kuehni, Rolf G.

2003-03-01

It has been postulated that humans can differentiate between millions of gradations in color. Not surprisingly, no completely adequate, detailed catalog of colors has yet been devised, however the quest to understand, record, and depict color is as old as the quest to understand the fundamentals of the physical world and the nature of human consciousness. Rolf Kuehni's Color Space and Its Divisions: Color Order from Antiquity to the Present represents an ambitious and unprecedented history of man's inquiry into color order, focusing on the practical applications of the most contemporary developments in the field. Kuehni devotes much of his study to geometric, three-dimensional arrangements of color experiences, a type of system developed only in the mid-nineteenth century. Color spaces are of particular interest for color quality-control purposes in the manufacturing and graphics industries. The author analyzes three major color order systems in detail: Munsell, OSA-UCS, and NCS. He presents historical and current information on color space developments in color vision, psychology, psychophysics, and color technology. Chapter topics include: A historical account of color order systems Fundamentals of psychophysics and the relationship between stimuli and experience Results of perceptual scaling of colors according to attributes History of the development of mathematical color space and difference formulas Analysis of the agreements and discrepancies in psychophysical data describing color differences An experimental plan for the reliable, replicated perceptual data necessary to make progress in the field Experts in academia and industry, neuroscientists, designers, art historians, and anyone interested in the nature of color will find Color Space and Its Divisions to be the authoritative reference in its field.

Strategizing for the Future: Evolving Cultural Resource Centers in Higher Education

Science.gov (United States)

Shek, Yen Ling

2013-01-01

Cultural resource centers have been an ongoing and integral component to creating a more welcoming campus climate for Students of Color since its establishment in the 1960s. While the racial dynamics may have changed, many of the challenges Students of Color faced on predominantly White campuses have not. Interestingly, cultural resource centers…

Full-color laser cathode ray tube (L-CRT) projector

Science.gov (United States)

Kozlovskiy, Vladimir; Nasibov, Alexander S.; Popov, Yuri M.; Reznikov, Parvel V.; Skasyrsky, Yan K.

1995-04-01

A full color TV projector based on three laser cathode-ray tubes (L-CRT) is described. A water-cooled laser screen (LS) is the radiation element of the L-CRT. We have produced three main colors (blue, green and red) by using the LS made of three II-VI compounds: ZnSe ((lambda) equals 475 nm), CdS ((lambda) equals 530 nm) and ZnCdSe (630 nm). The total light flow reaches 1500 Lm, and the number of elements per line is not less than 1000. The LS efficiency may be about 10 Lm/W. In our experiments we have tested new electron optics: - (30 - 37) kV are applied to the cathode unit of the electron gun; the anode of the e-gun and the e-beam intensity modulator are under low potential; the LS has a potential + (30 - 37) kV. The accelerating voltage is divided into two parts, and this enables us to diminish the size and weight of the projector.

Two-color mid-infrared spectroscopy of optically doped semiconductors

International Nuclear Information System (INIS)

Forcales, M.; Klik, M.A.J.; Vinh, N.Q.; Phillips, J.; Wells, J-P.R.; Gregorkiewicz, T.

2003-01-01

Optical doping is an attractive method to tailor photonic properties of semiconductor matrices for development of solid-state electroluminescent structures. For practical applications, thermal stability of emission obtained from these materials is required. Thermal processes can be conveniently investigated by two-color spectroscopy in the visible and the mid-infrared. Free-electron laser is a versatile high-brilliance source of radiation in the latter spectral range. In this contribution, we briefly review some of the results obtained recently by the two-color spectroscopy with a free-electron laser in different semiconductors optically doped with rare earth and transition metal ions. Effects leading to both enhancement and quenching of emission from optical dopants will be presented. For InP:Yb, Si:Er, and Si:Cu activation of particular optically induced non-radiative recombination paths will be shown. For Si:Er and Si:Ag, observation of a low temperature optical memory effect will be reported

COLORS AND COLOR GRADIENTS IN BULGES OF GALAXIES

NARCIS (Netherlands)

BALCELLS, M; PELETIER, RF

We have obtained surface photometry in U, B, R, and I for a complete optically selected sample of 45 early-type spiral galaxies, to investigate the colors and color gradients of spiral bulges. Color profiles in U-R, B-R, U-B, and R-I have been determined in wedges opening on the semiminor axes.

Pluto and Charon: Surface Colors and Compositions - A Hypothesis

Science.gov (United States)

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.

Examination of Color-Lighting Control System Using Colored Paper User Interface

OpenAIRE

Aida Hiroto; Matsui Kento; Keisuke Soma; Murakami Hiroki; Miki Mistunori

2016-01-01

In recent year, Full-Color LED Lighting that can be changed to various color such as red, green, blue has been appeared with development of LED Lighting. By Color-Lighting control, users affected such as concentrating and relaxing. Therefore, Color-lighting control will spread to various place such as home, offices, stations. However color-lighting control affected some disturbance such as daylight, display when Full-Color LED controlled indoors. Also, information devices control get difficul...

Full-color tuning in binary polymer:perovskite nanocrystals organic-inorganic hybrid blends

Science.gov (United States)

Perulli, A.; Balena, A.; Fernandez, M.; Nedelcu, G.; Cretí, A.; Kovalenko, M. V.; Lomascolo, M.; Anni, M.

2018-04-01

The excellent optical and electronic properties of metal halide perovskites recently proposed these materials as interesting active materials for optoelectronic applications. In particular, the high color purity of perovskite colloidal nanocrystals (NCs) had recently motivated their exploration as active materials for light emitting diodes with tunable emission across the visible range. In this work, we investigated the emission properties of binary blends of conjugated polymers and perovskite NCs. We demonstrate that the emission color of the blends is determined by the superposition of the component photoluminescence spectra, allowing color tuning by acting on the blend relative composition. The use of two different polymers, two different perovskite NCs, and different blend compositions is exploited to tune the blend color in the blue-green, yellow-red, and blue-red ranges, including white light generation.

Fast-responding liquid crystal light-valve technology for color-sequential display applications

Science.gov (United States)

Janssen, Peter J.; Konovalov, Victor A.; Muravski, Anatoli A.; Yakovenko, Sergei Y.

1996-04-01

A color sequential projection system has some distinct advantages over conventional systems which make it uniquely suitable for consumer TV as well as high performance professional applications such as computer monitors and electronic cinema. A fast responding light-valve is, clearly, essential for a good performing system. Response speed of transmissive LC lightvalves has been marginal thus far for good color rendition. Recently, Sevchenko Institute has made some very fast reflective LC cells which were evaluated at Philips Labs. These devices showed sub millisecond-large signal-response times, even at room temperature, and produced good color in a projector emulation testbed. In our presentation we describe our highly efficient color sequential projector and demonstrate its operation on video tape. Next we discuss light-valve requirements and reflective light-valve test results.

Phylloedes tumor of breast: findings at mammography, sonography and color Doppler imaging

International Nuclear Information System (INIS)

Park, Kun Choon; Ahn, Sei Hyun; Kim, Young Hwan; Choi, Hye Yong; Baek, Seung Yon; Yoon, Jeong Hyun

1994-01-01

The phylloides tumor of the breast is rare. the purposes of this study were to find the characteristic findings at mammography, sonography, and color Doppler imaging and to evaluate the usefulness of color Doppler study as an additional modality in the diagnosis of phylloides tumor and differentiation between benign and malignant varieties. Eight cases, who were pathologically proven as pylloides tumors, were retrospectively studied. The findings at histologic examination suggested benign in five, malignantin two, and borderline in one. We analyzed the mammograms of all eight patients and sonogram and color Doppler images of four patients. Phylloides tumors were seen as dense masses with lobulated margins in mammograms. On sonography, they showed relatively well-defined masses with in homogenous internal echo pattern and central echogenic areas. They were characterized by the presence of arterial and venous flows in the center and periphery of the lesion on color Doppler imaging and spectral analysis. We conclude that mammographic, sonographic and even color Doppler findings are not predictive of benign or malignant nature of the phylloides tumor. However, mammography and sonography with color Doppler interrogation are helpful in the diagnosis of phylloides tumor

Combining fine texture and coarse color features for color texture classification

Science.gov (United States)

Wang, Junmin; Fan, Yangyu; Li, Ning

2017-11-01

Color texture classification plays an important role in computer vision applications because texture and color are two fundamental visual features. To classify the color texture via extracting discriminative color texture features in real time, we present an approach of combining the fine texture and coarse color features for color texture classification. First, the input image is transformed from RGB to HSV color space to separate texture and color information. Second, the scale-selective completed local binary count (CLBC) algorithm is introduced to extract the fine texture feature from the V component in HSV color space. Third, both H and S components are quantized at an optimal coarse level. Furthermore, the joint histogram of H and S components is calculated, which is considered as the coarse color feature. Finally, the fine texture and coarse color features are combined as the final descriptor and the nearest subspace classifier is used for classification. Experimental results on CUReT, KTH-TIPS, and New-BarkTex databases demonstrate that the proposed method achieves state-of-the-art classification performance. Moreover, the proposed method is fast enough for real-time applications.

Characterization of Structural and Pigmentary Colors in Common Emigrant (Catopsilia Pomona) Butterfly

International Nuclear Information System (INIS)

Ghate, Ekata; Kulkarni, G. R.; Bhoraskar, S. V.; Adhi, K. P.

2011-01-01

Study of structural colors in case of insects and butterflies is important for their biomimic and biophotonics applications. Structural color is the color which is produced by physical structures and their interaction with light while pigmentary color is produced by absorption of light by pigments. Common Emigrant butterfly is widely distributed in India. It is of moderate size with wing span of about 60-80 mm. The wings are broadly white with yellow or sulphur yellow coloration at places as well as few dark black patches. It belongs to family Pieridae. A study of structural color in case of Common Emigrant butterfly has been carried out in the present work. The characterization of wing color was performed using absorption spectroscopy. Scanning electron microscopic study of the wings of Common Emigrant butterfly showed that three different types of scales are present on the wing surface dorsally. Diffracting structures are present in certain parts of the surfaces of the various scales. Bead like structures are embedded in the intricate structures of the scales. Absorption spectra revealed that a strong absorption peak is seen in the UV-range. Crystalline structure of beads was confirmed by the X-ray diffraction analysis.

A relativistic colored spinning particle in an external color field

International Nuclear Information System (INIS)

Heinz, U.

1984-01-01

I derive fully covariant equations of motion for a classical colored spinning particle in an external SU(3) color field. Although the total color charge and total spin of the particle are found to be separately constants of motion (here I disagree with a recent paper by Arodz), the dynamics of the orientation of the color and spin vectors are coupled to each other through interaction with the color field, even if the latter is homogeneous. (orig.)

Colored operads

CERN Document Server

Yau, Donald

2016-01-01

The subject of this book is the theory of operads and colored operads, sometimes called symmetric multicategories. A (colored) operad is an abstract object which encodes operations with multiple inputs and one output and relations between such operations. The theory originated in the early 1970s in homotopy theory and quickly became very important in algebraic topology, algebra, algebraic geometry, and even theoretical physics (string theory). Topics covered include basic graph theory, basic category theory, colored operads, and algebras over colored operads. Free colored operads are discussed in complete detail and in full generality. The intended audience of this book includes students and researchers in mathematics and other sciences where operads and colored operads are used. The prerequisite for this book is minimal. Every major concept is thoroughly motivated. There are many graphical illustrations and about 150 exercises. This book can be used in a graduate course and for independent study.

Color management of porcelain veneers: influence of dentin and resin cement colors.

Science.gov (United States)

Dozic, Alma; Tsagkari, Maria; Khashayar, Ghazal; Aboushelib, Moustafa

2010-01-01

Porcelain veneers have become an interesting treatment option to correct the shape and color of anterior teeth. Because of their limited thickness and high translucency, achieving a good color match is influenced by several variables. The aim of this work was to investigate the influence of natural dentin and resin cement colors on final color match of porcelain veneers. A preselected shade tab (A1) was chosen as the target color for a maxillary central incisor, and its color parameters (L*a*b*) were measured using a digital spectrophotometer (SpectroShade, MHT). Nine natural dentin colors (Natural Die Material, Ivoclar Vivadent) representing a wide range of tooth colors were used to prepare resin replicas of the maxillary central incisor with a standard preparation for porcelain veneers. The prepared porcelain veneers (IPS Empress Esthetic, A1, 0.6 mm thick, Ivoclar Vivadent) were cemented on the resin dies (nine groups of natural dentin colors) using seven shades of resin cement (Variolink Veneers, Ivoclar Vivadent). The L*a*b* values of the cemented veneers were measured, and DE values were calculated against the preselected target color (A1). DE greater than 3.3 was considered as a significant color mismatch detectable by the human eye. The seven shades of resin cement had no significant influence on the final color of the veneers, as the measured DE values were almost identical for every test group. On the other hand, the color of natural dentin was a significant factor that influenced final color match. None of the 63 tested combinations (nine natural dentin colors and seven resin cement colors) produced an acceptable color match. Thin porcelain veneers cannot mask underlying tooth color even when different shades of resin cement are used. Incorporation of opaque porcelain (high chroma) may improve final color match.

P1-15: Categorical Color Perception of LED Illuminant Color for Deuteranomals

Directory of Open Access Journals (Sweden)

Saeko Oishi

2012-10-01

Full Text Available Color information has great value in our everyday lives, but it is not mindful of people with color vision deficiency (CVD. We can choose several color names to categorize a lot of colors around us. Eleven color names (white, black, red, green, yellow, blue, brown, orange, pink, and gray are known as basic color categories, but people with CVD cannot necessarily describe colors as people who are color vision normal (CVN do. Previous studies showed that it was hard for people with CVD to discriminate illuminant color from object color, and their color perception changed largely depending on experimental conditions. In this study we investigated categorical color perception of illuminant color for deuteranomals, using a mixture of light which consists of a red, a green, and a blue LED as a test stimulus. We tested those stimuli with three luminance levels (180 cd/m2, 18 cd/m2, 1.8 cd/m2 and two visual angles (10 deg, 0.5 deg. Subjects were three deuteranomals and three people who are CVN. Our result showed that the categorical color of mild deuteranomals was similar to that of those who were CVN, but that of severe deuteranomals was not. Severe deuteranomals judged more low chromatic colors as achromatic colors than those who were CVN. The smaller visual angle or lower luminance level the test stimulus had, the more deuteranomals confused color. The results suggest that the effect of the Bezold-Brucke phenomenon is greater to deuteranomals than to those who are CVN. Furthermore, deuteranomals use not only chromatic information but also luminance information when they describe color.

Colored tracks of heavy ion particles recorded on photographic color film

International Nuclear Information System (INIS)

Kuge, K.; Yasuda, N.; Kumagai, H.; Aoki, N.; Hasegawa, A.

2002-01-01

A new method to obtain the three-dimensional information on nuclear tracks was developed using color photography. Commercial color films were irradiated with ion beam and color-developed. The ion tracks were represented with color images in which different depths were indicated by different colors, and the three-dimensional information was obtained from color changes. Details of this method are reported, and advantages and limitations are discussed in comparison with a conventional method using a nuclear emulsion

ColorTracker

NARCIS (Netherlands)

Holzheu, Stefanie; Lee, S.; Herneoja, Aulikki; Österlund, Toni; Markkanen, Piia

2016-01-01

With the work-in-progress research project ColorTracker we explore color as a formal design tool. This project-based paper describes a novel software application that processes color composition of a place and transcribes the data into three-dimensional geometries for architectural design. The

On-Demand Generation of Neutral and Negatively Charged Silicon-Vacancy Centers in Diamond

Science.gov (United States)

Dhomkar, Siddharth; Zangara, Pablo R.; Henshaw, Jacob; Meriles, Carlos A.

2018-03-01

Point defects in wide-band-gap semiconductors are emerging as versatile resources for nanoscale sensing and quantum information science, but our understanding of the photoionization dynamics is presently incomplete. Here, we use two-color confocal microscopy to investigate the dynamics of charge in type 1b diamond hosting nitrogen-vacancy (NV) and silicon-vacancy (SiV) centers. By examining the nonlocal fluorescence patterns emerging from local laser excitation, we show that, in the simultaneous presence of photogenerated electrons and holes, SiV (NV) centers selectively transform into the negative (neutral) charge state. Unlike NVs, 532 nm illumination ionizes SiV- via a single-photon process, thus hinting at a comparatively shallower ground state. In particular, slower ionization rates at longer wavelengths suggest the latter lies approximately ˜1.9 eV below the conduction band minimum. Building on the above observations, we demonstrate on-demand SiV and NV charge initialization over large areas via green laser illumination of variable intensity.

Deep reduced PEDOT films support electrochemical applications: Biomimetic color front.

Directory of Open Access Journals (Sweden)

Toribio Fernandez OTERO

2015-02-01

Full Text Available Most of the literature accepts, despite many controversial results, that during oxidation/reduction films of conducting polymers move from electronic conductors to insulators. Thus, engineers and device’s designers are forced to use metallic supports to reoxidize the material for reversible device work. Electrochromic front experiments appear as main visual support of the claimed insulating nature of reduced conducting polymers. Here we present a different design of the biomimetic electrochromic front that corroborates the electronic and ionic conducting nature of deep reduced films. The direct contact PEDOT metal/electrolyte and film/electrolyte was prevented from electrolyte contact until 1cm far from the metal contact with protecting Parafilm®. The deep reduced PEDOT film supports the flow of high currents promoting reaction induced electrochromic color changes beginning 1 cm far from the metal-polymer electrical contact and advancing, through the reduced film, towards the metal contact. Reverse color changes during oxidation/reduction always are initiated at the film/electrolyte contact advancing, under the protecting film, towards the film/metal contact. Both reduced and oxidized states of the film demonstrate electronic and ionic conductivities high enough to be used for electronic applications or, as self-supported electrodes, for electrochemical devices. The electrochemically stimulated conformational relaxation (ESCR model explains those results.

Colors in mind: a novel paradigm to investigate pure color imagery.

Science.gov (United States)

Wantz, Andrea L; Borst, Grégoire; Mast, Fred W; Lobmaier, Janek S

2015-07-01

Mental color imagery abilities are commonly measured using paradigms that involve naming, judging, or comparing the colors of visual mental images of well-known objects (e.g., "Is a sunflower darker yellow than a lemon"?). Although this approach is widely used in patient studies, differences in the ability to perform such color comparisons might simply reflect participants' general knowledge of object colors rather than their ability to generate accurate visual mental images of the colors of the objects. The aim of the present study was to design a new color imagery paradigm. Participants were asked to visualize a color for 3 s and then to determine a visually presented color by pressing 1 of 6 keys. We reasoned that participants would react faster when the imagined and perceived colors were congruent than when they were incongruent. In Experiment 1, participants were slower in incongruent than congruent trials but only when they were instructed to visualize the colors. The results in Experiment 2 demonstrate that the congruency effect reported in Experiment 1 cannot be attributed to verbalization of the color that had to be visualized. Finally, in Experiment 3, the congruency effect evoked by mental imagery correlated with performance in a perceptual version of the task. We discuss these findings with respect to the mechanisms that underlie mental imagery and patients suffering from color imagery deficits. (c) 2015 APA, all rights reserved.

Visual half-field presentations of incongruent color words: effects of gender and handedness.

Science.gov (United States)

Franzon, M; Hugdahl, K

1986-09-01

Right-handed (dextral) and left-handed (sinistral) males and females (N = 15) were compared for language lateralization in a visual half-field (VHF) incongruent color-words paradigm. The paradigm consists of repeated brief (less than 200 msec) presentations of color-words written in an incongruent color. Presentations are either to the right or to the left of center fixation. The task of the subject is to report the color the word is written in on each trial, ignoring the color-word. Color-bars and congruent color-words were used as control stimuli. Vocal reaction time (VRT) and error frequency were used as dependent measures. The logic behind the paradigm is that incongruent color-words should lead to a greater cognitive conflict when presented in the half-field contralateral to the dominant hemisphere. The results showed significantly longer VRTs in the right half-field for the dextral subjects. Furthermore, significantly more errors were observed in the male dextral group when the incongruent stimuli were presented in the right half-field. There was a similar trend in the data for the sinistral males. No differences between half-fields were observed for the female groups. It is concluded that the present results strengthen previous findings from our laboratory (Hugdahl and Franzon, 1985) that the incongruent color-words paradigm is a useful non-invasive technique for the study of lateralization in the intact brain.

ATR/OTR-SY Tank Camera Purge System and in Tank Color Video Imaging System

International Nuclear Information System (INIS)

Werry, S.M.

1995-01-01

This procedure will document the satisfactory operation of the 101-SY tank Camera Purge System (CPS) and 101-SY in tank Color Camera Video Imaging System (CCVIS). Included in the CPRS is the nitrogen purging system safety interlock which shuts down all the color video imaging system electronics within the 101-SY tank vapor space during loss of nitrogen purge pressure

Coloring mixed hypergraphs

CERN Document Server

Voloshin, Vitaly I

2002-01-01

The theory of graph coloring has existed for more than 150 years. Historically, graph coloring involved finding the minimum number of colors to be assigned to the vertices so that adjacent vertices would have different colors. From this modest beginning, the theory has become central in discrete mathematics with many contemporary generalizations and applications. Generalization of graph coloring-type problems to mixed hypergraphs brings many new dimensions to the theory of colorings. A main feature of this book is that in the case of hypergraphs, there exist problems on both the minimum and th

Study of optical absorption in the ultraviolet region of mixed crystals ADA/ADP aiming to investigate defects and centers formed by ionizing radiation

International Nuclear Information System (INIS)

Schneider, S.

1978-01-01

The development of a crystal model to explain the ionizing radiation effect on the color centers is presented. The methods of crystal growth used in the sample preparation and the requirements necessary for an efficient optical study, such as area, thickness purity, etc, are described. The processes of color center production are analysed and the techniques used in the study of color centers, such as optical absorption, spectrometry and spin resonance, are described. The computer programs used in curve adjustment and the approximated calculation of centers per cm 3 are also presented. (M.C.K.) [pt

Perception of color emotions for single colors in red-green defective observers.

Science.gov (United States)

Sato, Keiko; Inoue, Takaaki

2016-01-01

It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions). The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1) reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2) examine differences in color emotions related to the three cardinal channels in human color vision; and (3) explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP). Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance) as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth ratings in

Perception of color emotions for single colors in red-green defective observers

Directory of Open Access Journals (Sweden)

Keiko Sato

2016-12-01

Full Text Available It is estimated that inherited red-green color deficiency, which involves both the protan and deutan deficiency types, is common in men. For red-green defective observers, some reddish colors appear desaturated and brownish, unlike those seen by normal observers. Despite its prevalence, few studies have investigated the effects that red-green color deficiency has on the psychological properties of colors (color emotions. The current study investigated the influence of red-green color deficiency on the following six color emotions: cleanliness, freshness, hardness, preference, warmth, and weight. Specifically, this study aimed to: (1 reveal differences between normal and red-green defective observers in rating patterns of six color emotions; (2 examine differences in color emotions related to the three cardinal channels in human color vision; and (3 explore relationships between color emotions and color naming behavior. Thirteen men and 10 women with normal vision and 13 men who were red-green defective performed both a color naming task and an emotion rating task with 32 colors from the Berkeley Color Project (BCP. Results revealed noticeable differences in the cleanliness and hardness ratings between the normal vision observers, particularly in women, and red-green defective observers, which appeared mainly for colors in the orange to cyan range, and in the preference and warmth ratings for colors with cyan and purple hues. Similarly, naming errors also mainly occurred in the cyan colors. A regression analysis that included the three cone-contrasts (i.e., red-green, blue-yellow, and luminance as predictors significantly accounted for variability in color emotion ratings for the red-green defective observers as much as the normal individuals. Expressly, for warmth ratings, the weight of the red-green opponent channel was significantly lower in color defective observers than in normal participants. In addition, the analyses for individual warmth

Color Degree Sum Conditions for Rainbow Triangles in Edge-Colored Graphs

NARCIS (Netherlands)

Li, Ruonan; Ning, Bo; Zhang, Shenggui

Let G be an edge-colored graph and v a vertex of G. The color degree of v is the number of colors appearing on the edges incident to v. A rainbow triangle in G is one in which all edges have distinct colors. In this paper, we first prove that an edge-colored graph on n vertices contains a rainbow

What is Color Blindness?

Science.gov (United States)

... Color Blindness? Who Is at Risk for Color Blindness? Color Blindness Causes Color Blindness Diagnosis and Treatment How Color Blindness Is Tested What Is Color Blindness? Leer en Español: ¿Qué es el daltonismo? Written ...

Color Calibration for Colorized Vision System with Digital Sensor and LED Array Illuminator

Directory of Open Access Journals (Sweden)

Zhenmin Zhu

2016-01-01

Full Text Available Color measurement by the colorized vision system is a superior method to achieve the evaluation of color objectively and continuously. However, the accuracy of color measurement is influenced by the spectral responses of digital sensor and the spectral mismatch of illumination. In this paper, two-color vision system illuminated by digital sensor and LED array, respectively, is presented. The Polynomial-Based Regression method is applied to solve the problem of color calibration in the sRGB and CIE  L⁎a⁎b⁎ color spaces. By mapping the tristimulus values from RGB to sRGB color space, color difference between the estimated values and the reference values is less than 3ΔE. Additionally, the mapping matrix ΦRGB→sRGB has proved a better performance in reducing the color difference, and it is introduced subsequently into the colorized vision system proposed for a better color measurement. Necessarily, the printed matter of clothes and the colored ceramic tile are chosen as the application experiment samples of our colorized vision system. As shown in the experimental data, the average color difference of images is less than 6ΔE. It indicates that a better performance of color measurement is obtained via the colorized vision system proposed.

Colored solar collectors - Annual report 2006

Energy Technology Data Exchange (ETDEWEB)

Schueler, A.; Chambrier, E. De; Roecker, Ch.; Scartezzini, J.-L.

2007-12-15

The architectural integration of thermal solar collectors into buildings is often limited by their black color, and the visibility of tubes and corrugations of the absorber sheets. A certain freedom in color choice would be desirable, but the colored appearance should not cause an excessive degradation of the collector efficiency. Multilayered thin film interference filters on the collector glazing can produce a colored reflection, hiding the corrugated metal sheet, while transmitting the non-reflected radiation entirely to the absorber. These interference filters are designed and optimized by numerical simulation, and are manufactured by sol-gel dip-coating or magnetron sputtering. The novel colored glazed solar collectors will be ideally suited for architectural integration into buildings, e.g. as solar active glass facades. Due to the tunability of the refractive index, nanostructured materials such as SiO{sub 2}:TiO{sub 2} composites and porous SiO{sub 2} are very useful for application in multilayer interference stacks. Novel quaternary Mg-F-Si-O films exhibit a surprisingly low refractive index and are therefore promising candidates for highly transparent coatings on solar collector glazing. The nanostructure of these thin films is studied by transmission electron microscopy, while the optical constants are measured precisely by ellipsometry. For a convincing demonstration, sufficiently large samples of high quality are imperatively needed. The fabrication of nanocomposite SiO{sub 2}:TiO{sub 2} films has been demonstrated by sol-gel dip-coating of A4-sized glass panes. The produced coatings exhibit a colored reflection in combination with a high solar transmittance, a homogenous appearance, and are free of visible defects. Film hardening by UV exposure will result in speeding up the sol-gel process and saving energy, thereby reducing costs significantly. The infrastructure for UV-curing has been established. A UV C radiation source can now be attached to the

Photo darkening characterization and mechanisms

DEFF Research Database (Denmark)

Mattsson, Kent Erik

2010-01-01

+ formation. The color center becomes hereby either neutral oxygen vacancies that have received an electron to form E’ type color centers or by capture of a hole on surrounding anions such as (AlO4/20) reported for smoky quartz. In this presentation a phenomenological model for PD is suggested...... and the mechanism both of color center formation and the physics of the color center is described. Experimentally the induced PD is found to be either partially or fully reversed through temperature annealing or exposure to UV and/or visible light. Even bleach by the 915 nm pump power gives this possibility...

Multifunctional AgNPs@Wool: colored, UV-protective and antioxidant functional textiles

Science.gov (United States)

Shabbir, Mohd; Mohammad, Faqeer

2018-02-01

Nanomaterials have great impact on textile industry for multifunctional and smart clothing as per the need of present, and further, green nanotechnology is the current hotspot of research and industrial developments. Silver nanoparticles (AgNPs) are synthesized (in situ) by using natural compounds of plant extracts (naphthoquinones, phenolics/flavonoids, polyphenols) as reducing or stabilizing agents, and simultaneously deposited on wool fabric for coloration, UV protection and antioxidant properties. UV-visible spectroscopy is used to monitor the route of biosynthesis of nanoparticles and transmission electron microscopy for morphological characteristics of synthesized AgNPs. Spherical and almost oval-shaped AgNPs were synthesized by naphthoquinones, polyphenols and flavonoids, respectively. Scanning electron microscopy (SEM) coupled with energy dispersive X-ray (EDX) spectroscopy, X-ray diffraction pattern (XRD) and Fourier transform infrared spectroscopy were used for the AgNPs@Wool fabrics characterization. SEM-EDX analysis and XRD patterns confirmed the successful deposition of silver nanoparticles on wool. Coloration characteristics in terms of color strength (K/S) and CIEL*a*b*c*h° values, UV protection abilities in terms of UV transmittance and UV protection factor, and % antioxidant activity of AgNPs@Wool are suggestive of good-to-excellent results.

A flexible optically re-writable color liquid crystal display

Science.gov (United States)

Zhang, Yihong; Sun, Jiatong; Liu, Yang; Shang, Jianhua; Liu, Hao; Liu, Huashan; Gong, Xiaohui; Chigrinov, Vladimir; Kowk, Hoi Sing

2018-03-01

It is very difficult to make a liquid crystal display (LCD) that is flexible. However, for an optically re-writable LCD (ORWLCD), only the spacers and the substrates need to be flexible because the driving unit and the display unit are separate and there are no electronics in the display part of ORWLCD. In this paper, three flexible-spacer methods are proposed to achieve this goal. A cholesteric liquid crystal colored mirror with a polarizer behind it is used as the colored reflective backboard of an ORWLCD. Polyethersulfone substrates and flexible spacers are used to make the optically re-writable cell insensitive to mechanical force.

Clinical validation of a medical grade color monitor for chest radiology

Science.gov (United States)

Jacobs, J.; Zanca, F.; Verschakelen, J.; Marchal, G.; Bosmans, H.

2009-02-01

Until recently, the specifications of medical grade monochrome LCD monitors outperformed those of color LCD monitors. New generations of color LCD monitors, however, show specifications that are in many respects similar to those of monochrome monitors typically used in diagnostic workstations. The aim of present study was to evaluate the impact of different medical grade monitors in terms of detection of simulated lung nodules in chest x-ray images. Specifically, we wanted to compare a new medical grade color monitor (Barco Coronis 6MP color) to a medical grade grayscale monitor (Barco Coronis 3MP monochrome) and a consumer color monitor (Philips 200VW 1.7MP color) by means of an observer performance experiment. Using the free-response acquisition data paradigm, seven radiologists were asked to detect and locate lung nodules (170 in total), simulated in half of the 200 chest X-ray images used in the experiment. The jackknife free-response receiver operating characteristic (JAFROC) analysis of the data showed a statistically significant difference between at least two monitors, F-value=3.77 and p-value =0.0481. The different Figure of Merit values were 0.727, 0.723 and 0.697 for the new color LCD monitor, the medical grade monitor and the consumer color monitor respectively. There was no difference between the needed reading times but there was a difference between the mean calculated Euclidian distances between the position marked by the observers and the center of the simulated nodule, indicating a better accuracy with both medical grade monitors. Present data suggests that the new generation of medical grade color monitors could be used as diagnostic workstations.

Transpassive Dissolution of Copper and Rapid Formation of Brilliant Colored Copper Oxide Films

Science.gov (United States)

Fredj, Narjes; Burleigh, T. David; New Mexico Tech Team

2014-03-01

This investigation describes an electrochemical technique for growing adhesive copper oxide films on copper with attractive colors ranging from gold-brown to pearl with intermediate colors from red violet to gold green. The technique consists of anodically dissolving copper at transpassive potentials in hot sodium hydroxide, and then depositing brilliant color films of Cu2O onto the surface of copper after the anodic potential has been turned off. The color of the copper oxide film depends on the temperature, the anodic potential, the time t1 of polarization, and the time t2, which is the time of immersion after potential has been turned off. The brilliant colored films were characterized using glancing angle x-ray diffraction, and the film was found to be primarily Cu2O. Cyclic voltammetry, chronopotentiometry, scanning electron microscopy, and x-ray photoelectron spectroscopy were also used to characterize these films.

Full-color wide field-of-view holographic helmet-mounted display for pilot/vehicle interface development and human factors studies

Science.gov (United States)

Burley, James R., II; LaRussa, Joseph A.

1990-10-01

A Helmet-Mounted Display (HMD) which utilizes highly efficient trichromatic holographic elements has been designed to support pilot vechicle interface development and human factors studies at the NASA-Langley Research Center. While the optics are fully color corrected, the miniature CRT's are monochromatic. This design provides an upgrade path to full-color when miniature display technology matures to color. The optical design conforms to the helmet shape and provides a 50 degree field-of-view (FOV) to each eye. Built-in adjustments allow each ocular to be independently moved so that the overall horizontal FOV may be varied from 50 degrees to 100 degrees with a corresponding change in the stereo overlap region. The helmet design and interpupillary adjustment allow for the 5th through 95th percentile male and female wearer. Total head-borne weight is approximately 4.2 pounds. The high-resolution monochromatic CRTs are driven by a set of multisync electronics with a maximum video bandwidth of 88 Mhz and supports bith raster and stroke modes. The electronics are designed to be compatiable with the Silicon Graphics IRIS 4D graphics workstations and the ADAGE 340 stroke graphics computer. A Polhemus magnetic tracking device is used to determine the helmet line-of-sight. The helmet will be used to develop innovative new display concepts for the F- 1 8 High-Alpha Research Vehicle (HARV) which make use of the unique display properties of the HMD. Pictorial displays, which convey the appropriate information intuitively, are envisioned. Human factors studies are also planned to evaluate the utility of stereopsis and determine the FOV requirements for different tasks. Concepts proven in the simulator will be carried to flight test in 1993 with a lighter weight, "hardened" version of this HMD design.