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Sample records for extreme ultra violet

  1. Extreme ultra-violet movie camera for imaging microsecond time scale magnetic reconnection.

    Science.gov (United States)

    Chai, Kil-Byoung; Bellan, Paul M

    2013-12-01

    An ultra-fast extreme ultra-violet (EUV) movie camera has been developed for imaging magnetic reconnection in the Caltech spheromak/astrophysical jet experiment. The camera consists of a broadband Mo:Si multilayer mirror, a fast decaying YAG:Ce scintillator, a visible light block, and a high-speed visible light CCD camera. The camera can capture EUV images as fast as 3.3 × 10(6) frames per second with 0.5 cm spatial resolution. The spectral range is from 20 eV to 60 eV. EUV images reveal strong, transient, highly localized bursts of EUV radiation when magnetic reconnection occurs.

  2. Toward the Extreme Ultra Violet Four Wave Mixing Experiments: From Table Top Lasers to Fourth Generation Light Sources

    Directory of Open Access Journals (Sweden)

    Riccardo Cucini

    2015-01-01

    Full Text Available Three different Transient Grating setups are presented, with pulsed and continuous wave probe at different wavelengths, ranging from infrared to the extreme ultra violet region. Both heterodyne and homodyne detections are considered. Each scheme introduces variations with respect to the previous one, allowing moving from classical table top laser experiments towards a new four wave mixing scheme based on free electron laser radiation. A comparison between the various setups and the first results from extreme ultra violet transient grating experiments is also discussed.

  3. Analysis of observational data from Extreme Ultra-Violet Camera onboard Chang'E-3 mission

    Science.gov (United States)

    Yan, Yan; Wang, Hua-Ning; He, Han; He, Fei; Chen, Bo; Feng, Jian-Qing; Ping, Jin-Song; Shen, Chao; Xu, Rong-Lan; Zhang, Xiao-Xin

    2016-02-01

    The Extreme Ultra-Violet Camera (hereafter EUVC) is a scientific payload onboard the lander of the Chang'E-3 (hereafter CE-3) mission launched on December 1st, 2013. Centering on a spectral band around 30.4 nm, EUVC provides the global images of the Earth's plasmasphere from the meridian view, with a spatial resolution of 0.1 R_{oplus} in 150 × 150 pixels and a cadence of 10 minutes. Along with the data being publicly released online, some unsettled issues in the early stage have been clarified, including the geometrical preparations, the refined approach on the coefficient K for the background, and the alignment among the images. A demo of data after all the above processes is therefore presented as a guidance for users who are studying the structure and dynamics of the plasmasphere.

  4. Electronic structure, excitation properties, and chemical transformations of extreme ultra-violet resist materials

    Science.gov (United States)

    Rangan, Sylvie; Bartynski, Robert A.; Narasimhan, Amrit; Brainard, Robert L.

    2017-07-01

    The electronic structure of extreme ultra violet resist materials and of their individual components, two polymers and two photoacid generators (PAGs), is studied using a combination of x-ray and UV photoemission spectroscopies, electron energy loss spectroscopy, and ab-initio techniques. It is shown that simple molecular models can be used to understand the electronic structure of each sample and describe the experimental data. Additionally, effects directly relevant to the photochemical processes are observed: low energy loss processes are observed for the phenolic polymer containing samples that should favor thermalization of electrons; PAG segregation is measured at the surface of the resist films that could lead to surface inhomogeneities; both PAGs are found to be stable upon irradiation in the absence of the polymer, contrasting with a high reactivity that can be followed upon x-ray irradiation of the full resist.

  5. Fast resist-activation dosimetry for extreme ultra-violet lithography.

    Science.gov (United States)

    Heo, Jinseok; Xu, Man; Maas, Diederik

    2017-03-06

    Due to the rather broad band emission spectrum of the extremely hot plasma in its extreme ultra-violet (EUV) source, an EUV lithography scanner also projects out-of-band vacuum- and deep-UV (OoB V/DUV) light on the photoresist on a wafer. As this type of uncontrolled and undesirable light can activate resist chemistry, it will impair the critical dimension uniformity of the patterns, especially across the borders of the fields. Hence, OoB V/DUV quantification technology is required in the pre-production phase. For this reason, the systematic characterization of the EUV-source emission spectrum and the spatial profile of the light as projected on the wafer is indispensable to sustain stable integrated circuit production with EUV lithography. This paper introduces an in-band EUV and OoB V/DUV dosimetry method that is based on enhanced energy sensitivity by resist contrast (EESRC). This dosimetry method is applied in an EUV lithography tool to quantitatively analyze the spatial distribution the resist activation by in-band EUV and OoB V/DUV light, under several exposure conditions. This pragmatic approach can replace the current best-practice of measuring the full spectrum of an EUV light source.

  6. Radiation hardness of AlxGa1-xN photodetectors exposed to Extreme UltraViolet (EUV) light beam

    Science.gov (United States)

    Malinowski, Pawel E.; John, Joachim; Barkusky, Frank; Duboz, Jean Yves; Lorenz, Anne; Cheng, Kai; Derluyn, Joff; Germain, Marianne; De Moor, Piet; Minoglou, Kyriaki; Bayer, Armin; Mann, Klaus; Hochedez, Jean-Francois; Giordanengo, Boris; Borghs, Gustaaf; Mertens, Robert

    2009-05-01

    We report on the results of fabrication and optoelectrical characterization of Gallium Nitride (GaN) based Extreme UltraViolet (EUV) photodetectors. Our devices were Schottky photodiodes with a finger-shaped rectifying contact, allowing better penetration of light into the active region. GaN layers were epitaxially grown on Silicon (111) by Metal- Organic-Chemical Vapor Deposition (MOCVD). Spectral responsivity measurements in the Near UltraViolet (NUV) wavelength range (200-400 nm) were performed to verify the solar blindness of the photodetectors. After that the devices were exposed to the EUV focused beam of 13.5 nm wavelength using table-top EUV setup. Radiation hardness was tested up to a dose of 3.3Â.1019 photons/cm2. Stability of the quantum efficiency was compared to the one measured in the same way for a commercially available silicon based photodiode. Superior behavior of GaN devices was observed at the wavelength of 13.5 nm.

  7. Highly selective etching of SnO2 absorber in binary mask structure for extreme ultra-violet lithography.

    Science.gov (United States)

    Lee, Soo Jin; Jung, Chang Yong; Park, Sung Jin; Hwangbo, Chang Kweun; Seo, Hwan Seok; Kim, Sung Soo; Lee, Nae-Eung

    2012-04-01

    Among the core EUVL (extreme ultra-violet lithography) technologies for nanoscale patterning below the 30 nm node for Si chip manufacturing, new materials and fabrication processes for high-performance EUVL masks are of considerable importance due to the use of new reflective optics. In this work, the selective etching of SnO2 (tin oxide) as a new absorber material, with high EUV absorbance due to its large extinction coefficient, for the binary mask structure of SnO2 (absorber layer)/Ru (capping/etch stop layer)/Mo-Si multilayer (reflective layer)/Si (substrate), was investigated. Because infinitely high selectivity of the SnO2 layer to the Ru ESL is required due to the ultrathin nature of the Ru layer, various etch parameters were assessed in the inductively coupled Cl2/Ar plasmas in order to find the process window required for infinitely high etch selectivity of the SnO2 layer. The results showed that the gas flow ratio and V(dc) value play an important role in determining the process window for the infinitely high etch selectivity of SnO2 to Ru ESL. The high EUV-absorbance SnO2 layer, patternable by a dry process, allows a smaller absorber thickness, which can mitigate the geometric shadowing effects observed for high-performance binary EUVL masks.

  8. Critical dimension variation caused by wrinkle in extreme ultra-violet pellicle for 3-nm node

    Science.gov (United States)

    Kim, Guk-Jin; Kim, In-Seon; Lee, Sung-Gyu; Yeung, Michael; Kim, Min-Su; Park, Jin-Goo; Oh, Hye-Keun

    2017-10-01

    Extreme ultraviolet (EUV) pellicles help in the protection of EUV masks from defects, contaminants, and particles during the exposure process. However, a single-stack EUV pellicle can be easily deformed during the exposure process; therefore, multi-stack pellicles have been proposed to minimize the deformation of an EUV pellicle. However, wrinkles can be formed in an EUV pellicle due to extremely thin thickness. In this study, we investigated the impact of these wrinkles on the transmission and critical dimension (CD) variation for the 5- and 3-nm nodes. The 5- and 3-nm nodes can be used by conventional and high numerical aperture (NA) systems, respectively. The variation in the transmission and the allowable local tilt angle of the wrinkle as a function of the wrinkle height and periodicity were calculated. A change in transmission of 2.2% resulted in a 0.2 nm variation in the CD for the anamorphic NA system (3-nm node), whereas a transmission variation of 1.6% caused a 0.2 nm CD variation in the isomorphic NA system (5-nm node).

  9. Beyond Extreme Ultra Violet (BEUV) Radiation from Spherically symmetrical High-Z plasmas

    Science.gov (United States)

    Yoshida, Kensuke; Fujioka, Shinsuke; Higashiguchi, Takeshi; Ugomori, Teruyuki; Tanaka, Nozomi; Kawasaki, Masato; Suzuki, Yuhei; Suzuki, Chihiro; Tomita, Kentaro; Hirose, Ryouichi; Eshima, Takeo; Ohashi, Hayato; Nishikino, Masaharu; Scally, Enda; Nshimura, Hiroaki; Azechi, Hiroshi; O'Sullivan, Gerard

    2016-03-01

    Photo-lithography is a key technology for volume manufacture of high performance and compact semiconductor devices. Smaller and more complex structures can be fabricated by using shorter wavelength light in the photolithography. One of the most critical issues in development of the next generation photo-lithography is to increase energy conversion efficiency (CE) from laser to shorter wavelength light. Experimental database of beyond extreme ultraviolet (BEUV) radiation was obtained by using spherically symmetrical high-Z plasmas generated with spherically allocated laser beams. Absolute energy and spectra of BEUV light emitted from Tb, Gd, and Mo plasmas were measured with a absolutely calibrated BEUV calorimeter and a transmission grating spectrometer. 1.0 x 1012 W/cm2 is the optimal laser intensity to produced efficient BEUV light source plasmas with Tb and Gd targets. Maximum CE is achieved at 0.8% that is two times higher than the published CEs obtained with planar targets.

  10. Observations of solar coronal holes using radio (GMRT & GRH), extreme ultra-violet (SOHO-EIT) and X-ray (GOES-SXI) imaging instruments

    Science.gov (United States)

    Madsen, F. R. H.; Ramesh, R.; Ananthakrishnan, S.; Subramanian, P.; Cecatto, J. R.; Sawant, H. S.

    Solar observations with the Giant Metrewave Radio Telescope GMRT on 06 04 2005 at 150 MHz show evidence for a radio counterpart to a Coronal Hole CH observed as a depression in the radio brightness distribution on the solar disk In this work we compare the structural details of the radio CH using the GMRT observations and the Extreme Ultra Violet EUV and Soft X-Ray SXR images obtained with the SoHO EIT and GOES SXI respectively We also study the density temperature inside the same CH using 115 MHz data from the Gauribidanur Radioheliograph GRH We present and discuss our results for the radio counterpart to this CH focusing on the comparison of its position and size as determined from EUV and SXR with the parameters determined from the GMRT map and on the determination of plasma parameters from the GRH map

  11. Ultra Violet Imager on Venus Climate Orbiter

    Science.gov (United States)

    Yamada, M.; Watanabe, S.; Okano, S.; Imamura, T.; Nakamura, M.; Iwagami, N.; Keller, H. U.; Markiewicz, W. J.; Titov, D.

    We are developing a Ultra Violet Imager UVI which is one of the 5 cameras onboard the Venus Climate Orbiter VCO The VCO is the first planetary meteorological spacecraft and the cameras measuring different wavelength reveal atmospheric dynamics by cooperating with each other The Venus atmosphere has broad absorption of solar radiation between 200nm and 500nm The UVI is designed to measure the ultraviolet scattering lights at 283nm and 365nm wavelengths from cloud tops of sim 70km altitude The field of view is 0 015° with 1024x1024 SiCCD The spatial resolution is sim 15km at apoapsis of 13 Rv SO 2 at the cloud top absorbs the radiation in the region between 200nm and 320nm but the absorption above 320nm is due to unknown absorber Identification of the absorber is important for the energy balance and dynamics of the Venus atmosphere Tracking the cloud motion is used to investigate the dynamics of cloud winds and wave phenomena The typical size of the features is sim 100km and contrast is typically 5--10 The superrotation of the Venus cloud at sim 70km altitude has the zonal velocity of sim 100m s Therefore the imaging of clouds by the UVI will make clear the spatial and vertical distribution of the ultraviolet absorbers at the cloud tops identification of unknown absorber dynamics of cloud and vertical distribution of haze above the cloud Now we are testing the method to raise signal to noise ratio by use of an electrical breadboard model We will report the results of those tests

  12. Tests & Calibration on Ultra Violet Imaging Telescope (UVIT)

    CERN Document Server

    Kumar, Amit; Kamath, P U; Postma, Joe; Kathiravan, S; Mahesh, P K; S, Nagbhushana; Navalgund, K H; Rajkumar, N; Rao, M N; Sarma, K S; Sriram, S; Stalin, C S; Tandon, S N

    2012-01-01

    Ultra Violet Imaging Telescope on ASTROSAT Satellite mission is a suite of Far Ultra Violet (FUV; 130 to 180 nm), Near Ultra Violet (NUV; 200 to 300 nm) and Visible band (VIS; 320 to 550nm) imagers. ASTROSAT is a first multi wavelength mission of INDIA. UVIT will image the selected regions of the sky simultaneously in three channels & observe young stars, galaxies, bright UV Sources. FOV in each of the 3 channels is about 28 arc-minute. Targeted angular resolution in the resulting UV images is better than 1.8 arc-second (better than 2.0 arc-second for the visible channel). Two identical co-aligned telescopes (T1, T2) of Ritchey-Chretien configuration (Primary mirror of 375 mm diameter) collect the celestial radiation and feed to the detector system via a selectable filter on a filter wheel mechanism; gratings are available in the filter wheels of FUV and NUV channels for slit-less low resolution spectroscopy. The detector system for each of the 3 channels is generically identical. One telescope images in ...

  13. Vacuum ultra-violet and ultra-violet scintillation light detection by means of silicon photomultipliers at cryogenic temperature

    Energy Technology Data Exchange (ETDEWEB)

    Falcone, A., E-mail: andrea.falcone@pv.infn.it [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Bertoni, R. [INFN Sezione di Milano Bicocca, Piazza della Scienza, 3, 20126 Milano (Italy); Boffelli, F. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Bonesini, M. [INFN Sezione di Milano Bicocca, Piazza della Scienza, 3, 20126 Milano (Italy); Cervi, T. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); Menegolli, A. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Montanari, C.; Prata, M.C.; Rappoldi, A.; Raselli, G.L.; Rossella, M.; Simonetta, M. [INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Spanu, M. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); Torti, M. [University of Pavia, via Bassi, 6, 27100 Pavia (Italy); INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy); Zani, A. [INFN Sezione di Pavia, via Bassi, 6, 27100 Pavia (Italy)

    2015-07-01

    We tested the performance of two types of silicon photomultipliers, AdvanSiD ASD-NUV-SiPM3S-P and Hamamatsu 3×3 MM-50 UM VUV2, both at room (300 K) and at liquid nitrogen (77 K) temperature: breakdown voltage, quenching resistance, signal shape, gain and dark counts rate have been studied as function of temperature. The response of the devices to ultra-violet light is also studied. - Highlights: • We tested 2 SiPMs both at room and at cryogenic temperature. • Breakdown voltage, quenching resistance, gain and dark rate were measured. • Efficiency for VUV light detection was measured.

  14. Pulsed ultra-violet inactivation spectrum of Escherichia coli.

    Science.gov (United States)

    Wang, T; Macgregor, S J; Anderson, J G; Woolsey, G A

    2005-08-01

    Inactivation of Escherichia coli is examined using ultra-violet (UV) radiation from a pulsed xenon flashlamp. The light from the discharge has a broadband emission spectrum extending from the UV to the infrared region with a rich UV content. The flashlamp provides high-energy UV output using a small number of short-duration pulses (30 micros). The flashlamp is used with a monochromator to investigate the wavelength sensitivity of E. coli to inactivation by the pulsed UV light. Using 8 nm wide pulses of UV radiation, the most efficient inactivation is found to occur at around 270 nm and no inactivation is observed above 300 nm. A pyroelectric detector allows the energy dose to be determined at each wavelength, and a peak value for E. coli population reduction of 0.43 log per mJ/cm(2) is measured at 270 nm. The results are compared with the published data available for continuous UV light sources.

  15. White light emission from polystyrene under pulsed ultra violet laser irradiation

    Science.gov (United States)

    Kim, Eunkyeom; Kyhm, Jihoon; Kim, Jung Hyuk; Lee, Gi Yong; Ko, Doo-Hyun; Han, Il Ki; Ko, Hyungduk

    2013-01-01

    This paper reports for the first time the luminescent property of polystyrene (PS), produced by pulsed ultra violet laser irradiation. We have discovered that, in air, ultra-violet (UV) irradiated PS nanospheres emit bright white light with the dominant peak at 510 nm, while in vacuum they emit in the near-blue region. From the comparison of PS nanospheres irradiated in vacuum and air, we suggest that the white luminescence is due to the formation of carbonyl groups on the surface of PS by photochemical oxidation. Our results potentially offer a new route and strategy for white light sources. PMID:24247038

  16. Consequences of Ultra-Violet Irradiation on the Mechanical Properties of Spider Silk.

    Science.gov (United States)

    Lai, Wee Loong; Goh, Kheng Lim

    2015-09-10

    The outstanding combination of high tensile strength and extensibility of spider silk is believed to contribute to the material's toughness. Thus, there is great interest in engineering silk for biomedical products such as suture or implants. Additionally, over the years, many studies have also sought to enhance the mechanical properties of spider silk for wider applicability, e.g., by irradiating the material using ultra-violet radiation. However, the limitations surrounding the use of ultra-violet radiation for enhancing the mechanical properties of spider silk are not well-understood. Here, we have analyzed the mechanical properties of spider silk at short ultra-violet irradiation duration. Specimens of spider silk were subjected to ultra-violet irradiation (254-nm wavelength, i.e. UVC) for 10, 20, and 30 min, respectively, followed by tensile test to rupture to determine the strength (maximum stress), extensibility (rupture strain), and toughness (strain energy density to rupture). Controls, i.e., specimens that did not received UVC, were also subjected to tensile test to rupture to determine the respective mechanical properties. One-way analysis of variance reveals that these properties decrease significantly (p < 0.05) with increasing irradiation duration. Among the three mechanical parameters, the strength of the spider silk degrades most rapidly; the extensibility of the spider silk degrades the slowest. Overall, these changes correspond to the observed surface modifications as well as the bond rupture between the peptide chains of the treated silk. Altogether, this simple but comprehensive study provides some key insights into the dependence of the mechanical properties on ultra-violet irradiation duration.

  17. Consequences of Ultra-Violet Irradiation on the Mechanical Properties of Spider Silk

    Directory of Open Access Journals (Sweden)

    Wee Loong Lai

    2015-09-01

    Full Text Available The outstanding combination of high tensile strength and extensibility of spider silk is believed to contribute to the material’s toughness. Thus, there is great interest in engineering silk for biomedical products such as suture or implants. Additionally, over the years, many studies have also sought to enhance the mechanical properties of spider silk for wider applicability, e.g., by irradiating the material using ultra-violet radiation. However, the limitations surrounding the use of ultra-violet radiation for enhancing the mechanical properties of spider silk are not well-understood. Here, we have analyzed the mechanical properties of spider silk at short ultra-violet irradiation duration. Specimens of spider silk were subjected to ultra-violet irradiation (254-nm wavelength, i.e. UVC for 10, 20, and 30 min, respectively, followed by tensile test to rupture to determine the strength (maximum stress, extensibility (rupture strain, and toughness (strain energy density to rupture. Controls, i.e., specimens that did not received UVC, were also subjected to tensile test to rupture to determine the respective mechanical properties. One-way analysis of variance reveals that these properties decrease significantly (p < 0.05 with increasing irradiation duration. Among the three mechanical parameters, the strength of the spider silk degrades most rapidly; the extensibility of the spider silk degrades the slowest. Overall, these changes correspond to the observed surface modifications as well as the bond rupture between the peptide chains of the treated silk. Altogether, this simple but comprehensive study provides some key insights into the dependence of the mechanical properties on ultra-violet irradiation duration.

  18. Design Considerations for a Water Treatment System Utilizing Ultra-Violet Light Emitting Diodes

    Science.gov (United States)

    2014-03-27

    industry use for UV fluorescent bulb type water disinfection systems (Aquionics, 2013). Shorter wavelength LEDs (240 nm) were shown to be more...is in its infancy and research as it applies to UV water treatment is required to advance knowledge for practical application. This thesis focused...on two subjects. First, the design, fabrication, and operation of a water treatment reaction system utilizing Ultra-Violet ( UV ) Light Emitting

  19. A novel vacuum ultra violet lamp for metastable rare gas experiments

    CERN Document Server

    Daerr, Heiner; Sahling, Peter; Tippenhauer, Sandra; Arabi-Hashemi, Ariyan; Becker, Christoph; Sengstock, Klaus; Kalinowski, Martin B

    2011-01-01

    We report on a new design of a vacuum ultra violet (VUV) lamp for direct optical excitation of high laying atomic states e.g. for excitation of metastable rare gas atoms. The lamp can be directly mounted to ultra high vacuum vessels (p <= 10^(-10) mbar). It is driven by a 2.45 GHz microwave source. For optimum operation it requires powers of approximately 20 W. The VUV light is transmitted through a magnesium fluoride window, which is known to have a decreasing transmittance for VUV photons with time. In our special setup, after a run-time of the VUV lamp of 550 h the detected signal continuously decreased to 25 % of its initial value. This corresponds to a lifetime increase of two orders of magnitude compared to previous setups or commercial lamps.

  20. A novel vacuum ultra violet lamp for metastable rare gas experiments.

    Science.gov (United States)

    Daerr, Heiner; Kohler, Markus; Sahling, Peter; Tippenhauer, Sandra; Arabi-Hashemi, Ariyan; Becker, Christoph; Sengstock, Klaus; Kalinowski, Martin B

    2011-07-01

    We report on a new design of a vacuum ultra violet (VUV) lamp for direct optical excitation of high laying atomic states, e.g., for excitation of metastable rare gas atoms. The lamp can be directly mounted to ultra-high vacuum vessels (p ≤ 10(-10)mbar). It is driven by a 2.45 GHz microwave source. For optimum operation, it requires powers of ~20 W. The VUV light is transmitted through a magnesium fluoride window, which is known to have a decreasing transmittance for VUV photons with time. In our special setup, after a run-time of the VUV lamp of 550 h the detected signal continuously decreased to 25% of its initial value. This corresponds to a lifetime increase of two orders of magnitude compared to previous setups or commercial lamps.

  1. Effects of epigallocatechin gallate on ultra-violet-induced cell death in PC12 cells

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Hideo; Seki, Sakiko; Sakamoto, Naotaka; Nakagawa, Shigeki [Nihon Univ., Tokyo (Japan). School of Medicine

    2002-04-01

    We examined the effects of catechin on ultra-violet-induced cell death in PC12 cells. PC12 cells were irradiated by ultra-violet C (254 nm) (UVC). We found that the lactate dehydrogenase (LDH) activities in culture media and lipid peroxide in PC12 cells, which indicate cell death and cell membrane damage, respectively, were increased by UVC irradiation in a time-dependent manner. Cell death was gradually stimulated for 9 hours of cultivation after a UVC irradiation period of 10 or 30 min. Epigallocatechin gallate (EGCG), which is one of the main catechins found in green tea, suppressed the increase in LDH activity in culture medium and also inhibited the formation of lipid peroxide. I{kappa}B, a member of the cell death signaling system, was phosphorylated at 1 hour after 10 min of UVC irradiation. Stimulation of phosphorylation of I{kappa}B by UVC was suppressed by the addition of EGCG. We concluded that EGCG protects the PC12 cell from cell damage caused by UVC irradiation. (author)

  2. The strain specificity of vaccination with ultra violet attenuated cercariae of the Chinese strain of Schistosoma japonicum.

    Science.gov (United States)

    Moloney, N A; Garcia, E G; Webbe, G

    1985-01-01

    Mice vaccinated with ultra violet (u.v.) attenuated cercariae of the Chinese mainland strain of S. japonicum were resistant to homologous challenge, but were not resistant to challenge with the Philippine strain of S. japonicum. Thus vaccination using u.v. attenuated S. japonicum cercariae is strain specific.

  3. 1H NMR Study of Polyvinylalcohol Irradiated by Ultra-violet

    Institute of Scientific and Technical Information of China (English)

    Xiu Ling YAN; Wan Fu SUN; Jun TANG; Xin ZHAO

    2005-01-01

    The effect of Ultra-violet light on the structure and motion of the polyvinyl alcohol(PVA) chains was studied by 1H NMR, spin-lattice relaxation and IR spectroscopy. The results indicated that with the increase of irradiation time, the intensity of the polymer hydroxyl proton peaks decreased and finally vanished, which suggested the self-condensation between the hydroxyl groups proceeded. No methyl proton peaks appeared in the spectra after irradiation shows that there is no cleavage of polymer chain. The longer the irradiation time is, the wider the proton peak of the residual water of the solvent is and it shifted toward low field. This result implies that the hydrogen bonds formed between the polymer and the residual water. The absorption peak of hydroxyl group of the polymer moves toward the lower wave number in the IR spectrum that showed the existence of the hydrogen bonds between the PVA macromolecules.

  4. Effect of Montmorillonite Modification on Ultra Violet Radiation Cured Nanocomposite Filled with Glycidyl Methacrylate Modified Kenaf

    Science.gov (United States)

    Rozyanty, A. R.; Rozman, H. D.; Zhafer, S. F.; Musa, L.; Zuliahani, A.

    2016-06-01

    In this study nanocomposite cured by ultra violet radiation, were produced using modified montmorillonite (MMT) as reinforcing agent, chemically modified kenaf bast fiber as filler and unsaturated polyester as the matrix. Kenaf bast fiber was chemically modified with glycidyl methacrylate (GMA) whilst MMT were modified with cetyl trimethyl ammonium bromide (CTAB) and glycidyl methacrylate (GMA). Fixed 12 percent of GMA modified kenaf bast fiber with different percentage (i.e., 1, 3 and 5) of unmodified and modified MMT loading was used to produce the composite. The performed of GMA reaction with hydroxyl group of cellulose in kenaf bast fiber was evaluated using Fourier Transform infrared (FTIR) spectroscopy. GMA-MMT filled composite showed higher mechanical properties than MMT and CTAB-MMT filled composite. However, the increase of MMT, CTAB-MMT and GMA- MMT loading resulted in the reduction of mechanical properties. Scanning electron microscopy (SEM) analysis showed the evidence of compatibility enhancement between MMT and kenaf bast fiber with unsaturated polyester matrix.

  5. Measuring SO2 ship emissions with an ultra-violet imaging camera

    Science.gov (United States)

    Prata, A. J.

    2013-11-01

    Over the last few years fast-sampling ultra-violet (UV) imaging cameras have been developed for use in measuring SO2 emissions from industrial sources (e.g. power plants; typical fluxes ~1-10 kg s-1) and natural sources (e.g. volcanoes; typical fluxes ~10-100 kg s-1). Generally, measurements have been made from sources rich in SO2 with high concentrations and fluxes. In this work, for the first time, a UV camera has been used to measure the much lower concentrations and fluxes of SO2 (typical fluxes ~0.01-0.1 kg s-1) in the plumes from moving and stationary ships. Some innovations and trade-offs have been made so that estimates of the fluxes and path concentrations can be retrieved in real-time. Field experiments were conducted at Kongsfjord in Ny Ålesund, Svalbard, where emissions from cruise ships were made, and at the port of Rotterdam, Netherlands, measuring emissions from more than 10 different container and cargo ships. In all cases SO2 path concentrations could be estimated and fluxes determined by measuring ship plume speeds simultaneously using the camera, or by using surface wind speed data from an independent source. Accuracies were compromised in some cases because of the presence of particulates in some ship emissions and the restriction of single-filter UV imagery, a requirement for fast-sampling (>10 Hz) from a single camera. Typical accuracies ranged from 10-30% in path concentration and 10-40% in flux estimation. Despite the ease of use and ability to determine SO2 fluxes from the UV camera system, the limitation in accuracy and precision suggest that the system may only be used under rather ideal circumstances and that currently the technology needs further development to serve as a method to monitor ship emissions for regulatory purposes.

  6. Is ultra-violet radiation the main force shaping molecular evolution of varicella-zoster virus?

    Directory of Open Access Journals (Sweden)

    Escobar-Gutiérrez Alejandro

    2011-07-01

    Full Text Available Abstract Background Varicella (chickenpox exhibits a characteristic epidemiological pattern which is associated with climate. In general, primary infections in tropical regions are comparatively less frequent among children than in temperate regions. This peculiarity regarding varicella-zoster virus (VZV infection among certain age groups in tropical regions results in increased susceptibility during adulthood in these regions. Moreover, this disease shows a cyclic behavior in which the number of cases increases significantly during winter and spring. This observation further supports the participation of environmental factors in global epidemiology of chickenpox. However, the underlying mechanisms responsible for this distinctive disease behavior are not understood completely. In a recent publication, Philip S. Rice has put forward an interesting hypothesis suggesting that ultra-violet (UV radiation is the major environmental factor driving the molecular evolution of VZV. Discussion While we welcomed the attempt to explain the mechanisms controlling VZV transmission and distribution, we argue that Rice's hypothesis takes lightly the circulation of the so called "temperate VZV genotypes" in tropical regions and, to certain degree, overlooks the predominance of such lineages in certain non-temperate areas. Here, we further discuss and present new information about the overwhelming dominance of temperate VZV genotypes in Mexico regardless of geographical location and climate. Summary UV radiation does not satisfactorily explain the distribution of VZV genotypes in different tropical and temperate regions of Mexico. Additionally, the cyclic behavior of varicella does not shown significant differences between regions with different climates in the country. More studies should be conducted to identify the factors directly involved in viral spreading. A better understanding of the modes of transmissions exploited by VZV and their effect on viral

  7. An Ultra-Violet Tolerant Wild-Type Strain of Melanin-Producing Bacillus thuringiensis

    Science.gov (United States)

    Sansinenea, Estibaliz; Salazar, Francisco; Ramirez, Melanie; Ortiz, Aurelio

    2015-01-01

    Background: Bacillus thuringiensis is the most successful biological control agent used in agriculture, forestry and mosquito control. However, the insecticidal activity of the B. thuringiensis formulation is not very stable and rapidly loses its biological activity under field conditions, due to the ultraviolet radiation in sunlight. Melanin is known to absorb radiation therefore photo protection of B. thuringiensis based on melanin has been extensively studied. Objectives: The aim of this study was to find a wild type strain of naturally melanin-producing B. thuringiensis to avoid any mutation or manipulation that can affect the Cry protein content. Materials and Methods: Bacillus thuringiensis strains were isolated from soils of different States of Mexico and pigment extraction was followed by lowering the pH to 2 using 1N HCl. Pigment was characterized by some chemical tests based on its solubility, bleaching by H2O2 and flocculation with FeCl3, and using an Infrared (IR) spectrum. Ultraviolet (UV) irradiation experiment was performed to probe the melanin efficacy. Results: ELI52 strain of B. thuringiensis was confirmed to naturally produce melanin. The Cry protein analysis suggested that ELI52 is probably a B. thuringiensis subsp. israelensis strain with toxic activity against the Diptera order of insects. Ultra Violet protection efficacy of melanin was probed counting total viable colonies after UV radiation and comparing the results with the non-producing melanin strain L-DOPA (L-3, 4-dihydroxyphenylalanine) was also detected in the culture. ELI52 strain showed an antagonistic effect over some common bacteria from the environment. Conclusions: ELI52 wild-type strain of B. thuringiensis is a good bio-insecticide that produces melanin with UV-resistance that is probably toxic against the Diptera order of insects and can inhibit the growth of other environmental bacteria. PMID:26421136

  8. A Large Catalog of Homogeneous Ultra-Violet/Optical GRB Afterglows: Temporal and Spectral Evolution

    Science.gov (United States)

    Roming, Peter W. A.; Koch, T. Scott; Oates, Samantha R.; Porterfield, Blair L.; Bayless, Amanda J.; Breeveld, Alice A.; Gronwall, Caryl; Kuin, N. P. M.; Page, Mat J.; de Pasquale, Massimiliano; Siegel, Michael H.; Swenson, Craig A.; Tobler, Jennifer M.

    2017-02-01

    We present the second Swift Ultra-Violet/Optical Telescope (UVOT) gamma-ray burst (GRB) afterglow catalog, greatly expanding on the first Swift UVOT GRB afterglow catalog. The second catalog is constructed from a database containing over 120,000 independent UVOT observations of 538 GRBs first detected by Swift, the High Energy Transient Explorer 2 (HETE2), the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL), the Interplanetary Network (IPN), Fermi, and Astro-rivelatore Gamma a Immagini Leggero (AGILE). The catalog covers GRBs discovered from 2005 January 17 to 2010 December 25. Using photometric information in three UV bands, three optical bands, and a “white” or open filter, the data are optimally coadded to maximize the number of detections and normalized to one band to provide a detailed light curve. The catalog provides positional, temporal, and photometric information for each burst, as well as Swift Burst Alert Telescope and X-ray Telescope (XRT) GRB parameters. Temporal slopes are provided for each UVOT filter. The temporal slope per filter of almost half the GRBs are fit with a single power law, but one to three breaks are required in the remaining bursts. Morphological comparisons with the X-ray reveal that ∼ 75 % of the UVOT light curves are similar to one of the four morphologies identified by Evans et al. (2009). The remaining ∼ 25 % have a newly identified morphology. For many bursts, redshift- and extinction-corrected UV/optical spectral slopes are also provided at 2 × 103, 2 × 104, and 2 × 105 s.

  9. The induction of species-specific immunity against Schistosoma japonicum by exposure of rats to ultra-violet attenuated cercariae.

    Science.gov (United States)

    Moloney, N A; Webbe, G; Hinchcliffe, P

    1987-02-01

    Single percutaneous immunizations of Fischer rats with 1000 ultra-violet attenuated Schistosoma japonicum cercariae induced 52-88% resistance to challenge 4 weeks later. Increasing this to 3 immunizations induced 90% resistance to challenge, and this level of protection remained undiminished for up to 40 weeks after vaccination. Rats vaccinated with gamma-irradiated S. mansoni cercariae were resistant to challenge with S. mansoni but not S. japonicum. Similarly rats vaccinated with u.v.-attenuated S. japonicum cercariae were not resistant to heterologous challenge. Thus irradiated vaccines are species-specific in both permissive and non-permissive hosts.

  10. Induction of species-specific immunity against Schistosoma japonicum by exposure of rats to ultra-violet attenuated cercariae

    Energy Technology Data Exchange (ETDEWEB)

    Moloney, N.A.; Webbe, G.; Hinchcliffe, P.

    1987-02-01

    Single percutaneous immunizations of Fischer rats with 1000 ultra-violet attenuated Schistosoma japonicum cercariae induced 52-88% resistance to challenge 4 weeks later. Increasing this to 3 immunizations induced 90% resistance to challenge, and this level of protection remained undiminished for up to 40 weeks after vaccination. Rats vaccinated with gamma-irradiated S. mansoni cercariae were resistant to challenge with S. mansoni but not S. japonicum. Similarly rats vaccinated with u.v.-attenuated S. japonicum cercariae were not resistant to heterologous challenge. Thus irradiated vaccines are species-specific in both permissive and non-permissive hosts.

  11. 2-Chlorophenol Removal of Aqueous Solution Using Advanced Oxidation Processes Resulting from Iron/ Persulfate and Ultra Violet/ Persulfate

    Directory of Open Access Journals (Sweden)

    Shokufeh Astereki

    2016-06-01

    Full Text Available Background: Advanced oxidation processes are used to remove toxic aromatic compounds with low biodegradability, such as 2-chlorophenol. This study investigated the use of sulfate (SO4- and persulfate (S2O82- radicals, as one of the advanced oxidation methods, to remove 2- chlorophenol from aquatic solutions. Methods: This experimental and pilot-scale study was carried out using two chemical batch reactors; one of the reactors equipped with UV lamps and the other was on the hot plate. In iron/ persulfate (Fe/S2O82- and ultra violet/ persulfate (UV/S2O82- processes different parameters were investigated. Results: Iron, UV, the initial pH of the solution, persulfate concentration have considerable effects on the elimination of 2-chlorophenol in both processes. In both processes, the maximum elimination occurred in acidic conditions. The elimination efficiency was increased by increasing the concentration of 2-chlorophenol and UV intensity, and also by decreasing the concentration of persulfate and iron. Accordingly, in iron/ persulfate and ultra violet/ persulfate processes 2-chlorophenol was eliminated with 99.96% and 99.58% efficiencies, respectively. Conclusion: Sulfate radicals produced from activated persulfate ions with hot-Fe ion and UV radiation have significant impact on the removal of 2-chlorophenol. Therefore, the processes of Fe/S2O82- and UV/S2O82- can be regarded as good choices for industrial wastewater treatment plants operators in the future.

  12. Ultra-violet radiation is responsible for the differences in global epidemiology of chickenpox and the evolution of varicella-zoster virus as man migrated out of Africa

    Directory of Open Access Journals (Sweden)

    Rice Philip S

    2011-04-01

    Full Text Available Abstract Background Of the eight human herpes viruses, varicella-zoster virus, which causes chickenpox and zoster, has a unique epidemiology. Primary infection is much less common in children in the tropics compared with temperate areas. This results in increased adult susceptibility causing outbreaks, for example in health-care workers migrating from tropical to temperate countries. The recent demonstration that there are different genotypes of varicella-zoster virus and their geographic segregation into tropical and temperate areas suggests a distinct, yet previously unconsidered climatic factor may be responsible for both the clinical and molecular epidemiological features of this virus infection. Presentation of the hypothesis Unlike other human herpes viruses, varicella-zoster virus does not require intimate contact for infection to occur indicating that transmission may be interrupted by a geographically restricted climatic factor. The factor with the largest difference between tropical and temperate zones is ultra-violet radiation. This could reduce the infectiousness of chickenpox cases by inactivating virus in vesicles, before or after rupture. This would explain decreased transmissibility in the tropics and why the peak chickenpox incidence in temperate zones occurs during winter and spring, when ultra-violet radiation is at its lowest. The evolution of geographically restricted genotypes is also explained by ultra-violet radiation driving natural selection of different virus genotypes with varying degrees of resistance to inactivation, tropical genotypes being the most resistant. Consequently, temperate viruses should be more sensitive to its effects. This is supported by the observation that temperate genotypes are found in the tropics only in specific circumstances, namely where ultra-violet radiation has either been excluded or significantly reduced in intensity. Testing the Hypothesis The hypothesis is testable by exposing

  13. Photostability Characterization of Wood Polymer Composites of Polyvinyl Chloride and Rice Husk to Ultra-Violet Irradiation Exposure

    Directory of Open Access Journals (Sweden)

    Jais Farhana Hazwanee M.

    2016-01-01

    Full Text Available In this study, the photostability of wood polymer composites (WPC was assessed by using ultra-violet accelerated weathering test. Meanwhile, the mechanical properties of WPC show strength improvement at prolonged UV irradiation exposure with 43.21 MPa and maximum strain of 4.08 % at 5000 hours and 1000 hours UV irradiation exposure respectively. The colour stability of WPC was improved by addition of Ultraviolet (UV stabilizer during pre-mixing process which shows positive effect on the colour stability and prevented chalking of the composites for external use. Generally, discolourations of WPC during test exposure were caused by degradation of both wood and plastic. Therefore, incorporation with pigments and other additives gives improvement to the photostability of WPC. This is based on the increment of WPCs mechanical property while the morphological fracture surface of dumbbell test specimens revealed the pull out rice husk fiber which contributed to the distribution of load in the WPC samples.

  14. ANALYSIS OF DIFFERENT BRANDS OF PARACETAMOL 500mg TABLETS USED IN MAIDUGURI, USING ULTRA VIOLET SPECTROPHOTOMETRIC AND HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC (HPLC) METHODS

    OpenAIRE

    Sani Ali Audu; Alemika Emmanuel Taiwo; Bala Fatima Mohammed; Sani Musa; Ramat. Bukola

    2012-01-01

    The study involves quantitative analysis of eight (8) different brands (samples) of Paracetamol 500mg tablets used in Maiduguri, using Ultra Violet Spectrophotometric and High Performance Liquid Chromatographic methods, in which the samples were dissolved in 0.1M NaOH and distilled water and their various absorbances determined at wavelength of 257nm and the HPLC method. The results obtained were compared with that of the standard. Percentage content and content in mg for each sample was calc...

  15. Low-loss optical waveguides for the near ultra-violet and visible spectral regions with Al{sub 2}O{sub 3} thin films from atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Aslan, Mustafa M.; Webster, Nathan A.; Byard, Courtney L.; Pereira, Marcelo B.; Hayes, Colin M.; Wiederkehr, Rodrigo S. [Department of Physics and Astronomy, University of Louisville, Louisville, KY, 40292 (United States); Mendes, Sergio B., E-mail: sbmend01@louisville.ed [Department of Physics and Astronomy, University of Louisville, Louisville, KY, 40292 (United States)

    2010-06-30

    In this work, we report low-loss single-mode integrated optical waveguides in the near ultra-violet and visible spectral regions with aluminum oxide (Al{sub 2}O{sub 3}) films using an atomic layer deposition (ALD) process. Alumina films were deposited on glass and fused silica substrates by the ALD process at substrate/chamber temperatures of 200 {sup o}C and 300 {sup o}C. Transmission spectra and waveguide measurements were performed in our alumina films with thicknesses in the range of 210-380 nm for the optical characterization. Those measurements allowed us to determine the optical constants (n{sub w} and k{sub w}), propagation loss, and thickness of the alumina films. The experimental results from the applied techniques show good agreement and demonstrate a low-loss optical waveguide. Our alumina thin-film waveguides are well transparent in the whole visible spectral region and also in an important region of the UV; the measured propagation loss is below 4 dB/cm down to a wavelength as short as 250 nm. The low propagation loss of these alumina guiding films, in particular in the near ultra-violet region which lacks materials with high optical performance, is extremely useful for several integrated optic applications.

  16. [Detection of glucocorticoids by pressurized capillary electrochromatography with ultra-violet detection and its application in hair analysis].

    Science.gov (United States)

    Li, Boxiang; Zheng, Minmin; Lu, Lanxiang; Wu, Xiaoping

    2011-08-01

    An effective and convenient method for glucocorticoid analysis in hair by reversed-phase pressurized capillary electrochromatography (pCEC) with ultra-violet (UV) detection was developed. Eight glucocorticoids (betamethasone, dexamethasone, prednisone, prednisolone, prednisolone acetate, hydrocortisone acetate, cortisone acetate and corticosterone) were separated within 20 min in an isocratic mode pCEC. The separations were performed on a reversed-phase C18 column, and with 245 nm as the UV detection wavelength. The mobile phase was composed of 1.5 mmol/L Tris buffer (pH 8.0) and acetonitrile (65: 35, v/v), at a pump flow rate of 0.105 mL/min. All of the compounds showed good linearity in the range of 0.036 - 4.0 mmol/L. The limits of detection (LODs) for all glucocorticoids were of microg/g levels. The proposed method was applied to the analysis of hair samples. The interference of hair matrices was effectively eliminated by protein enzymatic digestion, followed by a methanol extraction and a solid phase extraction (SPE) clean up step. The average recoveries of 71% - 85% at different fortified levels of glucocorticoids were achieved. This non-invasive method is useful for rapidly estimating the level of drug exposure in drug chronic abuse and monitoring the compliance of therapeutic drugs.

  17. Reaction of photochemical resists used in screen printing under the influence of digitally modulated ultra violet light

    Science.gov (United States)

    Gmuender, T.

    2017-02-01

    Different chemical photo-reactive emulsions are used in screen printing for stencil production. Depending on the bandwidth, optical power and depth of field from the optical system, the reaction / exposure speed has a diverse value. In this paper, the emulsions get categorized and validated in a first step. After that a mathematical model gets developed and adapted due to heuristic experience to estimate the exposure speed under the influence of digitally modulated ultra violet (UV) light. The main intention is to use the technical specifications (intended wavelength, exposure time, distance to the stencil, electrical power, stencil configuration) in the emulsion data sheet primary written down with an uncertainty factor for the end user operating with large projector arc lamps and photo films. These five parameters are the inputs for a mathematical formula which gives as an output the exposure speed for the Computer to Screen (CTS) machine calculated for each emulsion / stencil setup. The importance of this work relies in the possibility to rate with just a few boundaries the performance and capacity of an exposure system used in screen printing instead of processing a long test series for each emulsion / stencil configuration.

  18. A spectroscopic study on the effect of ultra-violet solar radiation in Antarctica on the human skin fibroblast cells

    Directory of Open Access Journals (Sweden)

    Tatsuyuki Yamamoto

    2013-11-01

    Full Text Available A study on the effect of the solar ultra-violet radiation on the human skin fibroblast cells revealed that the production of matrix metalloproteinase-2 was inhibited by the radiation. A CO2 incubator connected by optical fibers to a reflector telescope for collecting the solar light was built at Syowa station by the 49th Japanese Antarctica Research Expedition. The direction of the telescope was continuously controlled by a sun-tracker to follow the movement of the Sun automatically. The intensity of the collected light was monitored by a portable spectrophotometer housed inside. The human skin fibroblast cells were incubated in the CO2 chamber to investigate the effect of the solar radiation at Syowa station and were compared with those reference experiments at a laboratory in Japan. The results showed cell damage by strong UV radiation. The production of matrix metalloproteinase-2 was prompted by the moderate UV-B, but was inhibited by the strong UV-B radiation, as studied under laboratory conditions in Japan. The effect of strong solar radiation at Syowa station involving the radiation of UV-B region was estimated to be of the same extent of the radiation caused by an artificial UV-B light with the intensity more than 50 mJ/cm2.

  19. Modeling the Effects of Star Formation Histories on Halpha and Ultra-Violet Fluxes in Nearby Dwarf Galaxies

    CERN Document Server

    Weisz, Daniel R; Johnson, L Clifton; Skillman, Evan D; Lee, Janice C; Kennicutt, Robert C; Calzetti, Daniela; van Zee, Liese; Bothwell, Matthew; Dalcanton, Julianne J; Dale, Daniel A; Williams, Benjamin F

    2011-01-01

    We consider the effects of non-constant star formation histories (SFHs) on Halpha and GALEX far ultra-violet (FUV) star formation rate (SFR) indicators. Under the assumption of a fully populated Chabrier IMF, we compare the distribution of Halpha-to-FUV flux ratios from ~ 1500 simple, periodic model SFHs with observations of 185 galaxies from the Spitzer Local Volume Legacy survey. We find a set of SFH models that are well matched to the data, such that more massive galaxies are best characterized by nearly constant SFHs, while low mass systems experience bursts amplitudes of ~ 30 (i.e., an increase in the SFR by a factor of 30 over the SFR during the inter-burst period), burst durations of tens of Myr, and periods of ~ 250 Myr; these SFHs are broadly consistent with the increased stochastic star formation expected in systems with lower SFRs. We analyze the predicted temporal evolution of galaxy stellar mass, R-band surface brightness, Halpha-derived SFR, and blue luminosity, and find that they provide a reas...

  20. Vacuum ultra-violet damage and damage mitigation for plasma processing of highly porous organosilicate glass dielectrics

    Energy Technology Data Exchange (ETDEWEB)

    Marneffe, J.-F. de, E-mail: marneffe@imec.be; Lukaszewicz, M.; Porter, S. B.; Vajda, F.; Rutigliani, V.; Verdonck, P.; Baklanov, M. R. [IMEC v.z.w., 3001 Leuven (Belgium); Zhang, L.; Heyne, M.; El Otell, Z.; Krishtab, M. [IMEC v.z.w., 3001 Leuven (Belgium); Department of Chemistry, KULeuven, 3001 Leuven (Belgium); Goodyear, A.; Cooke, M. [Oxford Instruments Plasma Technology, BS49 4AP Bristol (United Kingdom)

    2015-10-07

    Porous organosilicate glass thin films, with k-value 2.0, were exposed to 147 nm vacuum ultra-violet (VUV) photons emitted in a Xenon capacitive coupled plasma discharge. Strong methyl bond depletion was observed, concomitant with a significant increase of the bulk dielectric constant. This indicates that, besides reactive radical diffusion, photons emitted during plasma processing do impede dielectric properties and therefore need to be tackled appropriately during patterning and integration. The detrimental effect of VUV irradiation can be partly suppressed by stuffing the low-k porous matrix with proper sacrificial polymers showing high VUV absorption together with good thermal and VUV stability. In addition, the choice of an appropriate hard-mask, showing high VUV absorption, can minimize VUV damage. Particular processing conditions allow to minimize the fluence of photons to the substrate and lead to negligible VUV damage. For patterned structures, in order to reduce VUV damage in the bulk and on feature sidewalls, the combination of both pore stuffing/material densification and absorbing hard-mask is recommended, and/or the use of low VUV-emitting plasma discharge.

  1. Observing the Forest Canopy with a New Ultra-Violet Compact Airborne Lidar

    Directory of Open Access Journals (Sweden)

    Dominique Guyon

    2010-08-01

    Full Text Available We have developed a new airborne UV lidar for the forest canopy and deployed it in the Landes forest (France. It is the first one that: (i operates at 355 nm for emitting energetic pulses of 16 mJ at 20 Hz while fulfilling eye-safety regulations and (ii is flown onboard an ultra-light airplane for enhanced flight flexibility. Laser footprints at ground level were 2.4 m wide for a flying altitude of 300 m. Three test areas of ~500 × 500 m2 with Maritime pines of different ages were investigated. We used a threshold method adapted for this lidar to accurately extract from its waveforms detailed forest canopy vertical structure: canopy top, tree crown base and undergrowth heights. Good detection sensitivity enabled the observation of ground returns underneath the trees. Statistical and one-to-one comparisons with ground measurements by field foresters indicated a mean absolute accuracy of ~1 m. Sensitivity tests on detection threshold showed the importance of signal to noise ratio and footprint size for a proper detection of the canopy vertical structure. This UV-lidar is intended for future innovative applications of simultaneous observation of forest canopy, laser-induced vegetation fluorescence and atmospheric aerosols.

  2. Observing the forest canopy with a new ultra-violet compact airborne lidar.

    Science.gov (United States)

    Cuesta, Juan; Chazette, Patrick; Allouis, Tristan; Flamant, Pierre H; Durrieu, Sylvie; Sanak, Joseph; Genau, Pascal; Guyon, Dominique; Loustau, Denis; Flamant, Cyrille

    2010-01-01

    We have developed a new airborne UV lidar for the forest canopy and deployed it in the Landes forest (France). It is the first one that: (i) operates at 355 nm for emitting energetic pulses of 16 mJ at 20 Hz while fulfilling eye-safety regulations and (ii) is flown onboard an ultra-light airplane for enhanced flight flexibility. Laser footprints at ground level were 2.4 m wide for a flying altitude of 300 m. Three test areas of ≈ 500 × 500 m(2) with Maritime pines of different ages were investigated. We used a threshold method adapted for this lidar to accurately extract from its waveforms detailed forest canopy vertical structure: canopy top, tree crown base and undergrowth heights. Good detection sensitivity enabled the observation of ground returns underneath the trees. Statistical and one-to-one comparisons with ground measurements by field foresters indicated a mean absolute accuracy of ≈ 1 m. Sensitivity tests on detection threshold showed the importance of signal to noise ratio and footprint size for a proper detection of the canopy vertical structure. This UV-lidar is intended for future innovative applications of simultaneous observation of forest canopy, laser-induced vegetation fluorescence and atmospheric aerosols.

  3. Observing the Forest Canopy with a New Ultra-Violet Compact Airborne Lidar

    Science.gov (United States)

    Cuesta, Juan; Chazette, Patrick; Allouis, Tristan; Flamant, Pierre H.; Durrieu, Sylvie; Sanak, Joseph; Genau, Pascal; Guyon, Dominique; Loustau, Denis; Flamant, Cyrille

    2010-01-01

    We have developed a new airborne UV lidar for the forest canopy and deployed it in the Landes forest (France). It is the first one that: (i) operates at 355 nm for emitting energetic pulses of 16 mJ at 20 Hz while fulfilling eye-safety regulations and (ii) is flown onboard an ultra-light airplane for enhanced flight flexibility. Laser footprints at ground level were 2.4 m wide for a flying altitude of 300 m. Three test areas of ∼500 × 500 m2 with Maritime pines of different ages were investigated. We used a threshold method adapted for this lidar to accurately extract from its waveforms detailed forest canopy vertical structure: canopy top, tree crown base and undergrowth heights. Good detection sensitivity enabled the observation of ground returns underneath the trees. Statistical and one-to-one comparisons with ground measurements by field foresters indicated a mean absolute accuracy of ∼1 m. Sensitivity tests on detection threshold showed the importance of signal to noise ratio and footprint size for a proper detection of the canopy vertical structure. This UV-lidar is intended for future innovative applications of simultaneous observation of forest canopy, laser-induced vegetation fluorescence and atmospheric aerosols. PMID:22163608

  4. Durable silver mirror with ultra-violet thru far infra-red reflection

    Science.gov (United States)

    Wolfe, Jesse D.

    2010-11-23

    A durable highly reflective silver mirror characterized by high reflectance in a broad spectral range of about 300 nm in the UV to the far infrared (.about.10000 nm), as well as exceptional environmental durability. A high absorptivity metal underlayer is used which prevents the formation of a galvanic cell with a silver layer while increasing the reflectance of the silver layer. Environmentally durable overcoat layers are provided to enhance mechanical and chemical durability and protect the silver layer from corrosion and tarnishing, for use in a wide variety of surroundings or climates, including harsh or extreme environments.

  5. Durable silver mirror with ultra-violet thru far infra-red reflection

    Energy Technology Data Exchange (ETDEWEB)

    Wolfe, Jesse D. (Discovery Bay, CA)

    2010-11-23

    A durable highly reflective silver mirror characterized by high reflectance in a broad spectral range of about 300 nm in the UV to the far infrared (.about.10000 nm), as well as exceptional environmental durability. A high absorptivity metal underlayer is used which prevents the formation of a galvanic cell with a silver layer while increasing the reflectance of the silver layer. Environmentally durable overcoat layers are provided to enhance mechanical and chemical durability and protect the silver layer from corrosion and tarnishing, for use in a wide variety of surroundings or climates, including harsh or extreme environments.

  6. Influence of small dozes ultra-violet radiation on motion of dislocation in alkali-halide crystals

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    The purpose of this work was research into influence of ultra-violet radiation on size of run of regional and screw dislocations in beams of dislocation sockets, formed at indentation surface of alkali-halide crystals. In experiments it was used crystals NaCl, with the quantitative maintenance of impurity 10-2 -10-3weight%, the wave length of UV-radiation λ=250 nanometers, the sizes of samples 10mm× 20mm× 2mm,temperature of samples was constant T=290 K.It is established that indentation and the simultaneous irradiation of samples a ultraviolet is increases size of run of head dispositions in dislocation sockets..It is marked, that influence UV-radiation nonequivalence for various times of an exposition. At small times (till 5 minutes) the size of run grows. The length of beams increases on ~ 50 %. At the further increase in time of influence of a ultraviolet the length of beams is reduced till the sizes corresponding stressing without an irradiation (Figs. 1, 2, 3). The effect is observed on dislocation beams of regional and screw orientations and most expressed at small loadings (in our experiments-10 grams) (Fig. 3).Observable effects are explained from positions dislocation-exciton interactions. At UV-radiation exciton cooperates with the charged step on a disposition, causing movement of a step along a disposition on one internuclear distance. Due to this interaction overcoming by a disposition of a grid of stoppers is facilitated.Big times of endurance cause a relaxation of pressure directly in a print that provides convertible movement of dispositions in area of a print and as consequence, reduction of length of beams of dislocation sockets.

  7. New technologies to enhance quality and safety of table eggs: ultra-violet treatment and modified atmosphere packaging

    Directory of Open Access Journals (Sweden)

    Frédérique Pasquali

    2014-12-01

    Full Text Available In the present study the effect of ultra-violet (UV treatment alone and in combination with 100% CO2 modified atmosphere packaging (MAP was evaluated both on the survival of naturally occurring bacteria, as well as on quality parameters of table eggs during 28 days of storage at 21°C. Table eggs were collected from the conveyor belt after the UV module, and placed on carton trays. A representative number of carton trays were packed in a high barrier multilayer pouch filled with 100% CO2. All eggs were stored at 21°C and analysed at 0, 1, 7, 14, 21 and 28 days of storage. Eggs not treated with UV and not packed were also included. On the eggshells total colony count, total coliforms and faecal coliforms counts, as well as the detection of Salmonella spp. were investigated. Moreover, chemical-functional parameters such as weight loss, albumen pH and Haugh Unit (HU were evaluated. The total colony count on UV treated table eggs was approximately 1 log10 CFU/g lower than untreated eggs (2.27 vs 3.29 log10 CFU/g. During storage, CO2 packed eggs maintained the initial values of HU, whereas the albumen pH decreased up to 1.5-2 points in comparison to unpacked eggs. The UV treatment was effective in reducing the total colony count on the surface of table eggs. MAP showed a great potential in maintaining/enhance the technological properties of egg constituents (higher foam stability of the albumen for meringue preparation without significantly impacting on the microbial load of table eggs.

  8. Fabrication and characterization of p-ZnO:(P,N)/n-ZnO:Al homojunction ultra-violet (UV) light emitting diodes (Presentation Recording)

    Science.gov (United States)

    Rafiudeen, Amiruddin; Reddy, T. Srinivasa; Cheemadan, Shaheer; Kumar, M. C. Santhosh

    2015-10-01

    ZnO possess distinctive characteristics such as low cost, wide band gap (3.36 eV) and large exciton binding energy (60meV). As the band gap lies in ultra violet (UV) region, ZnO is considered as a novel material for the fabrication of ultra violet light emitting diodes (UV-LEDs). However, ZnO being intrinsic n-type semiconductor the key challenge lies in realization of stable and reproducible p-type ZnO. In the present research dual acceptor group-V elements such as P and N are simultaneously doped in ZnO films to obtain the p-type characteristics. The deposition is made by programmable spray pyrolysis technique upon glass substrates at 697K. The optimum doping concentration of P and N were found to be 0.75 at% which exhibits hole concentration of 4.48 x 10^18 cm-3 and resistivity value of 9.6 Ω.cm. The deposited p-ZnO were found to be stable for a period over six months. Highly conducting n-type ZnO films is made by doping aluminum (3 at%) which exhibits higher electron concentration of 1.52 x 10^19 cm-3 with lower electrical resistivity of 3.51 x 10-2 Ω.cm. The structural, morphological, optical and electrical properties of the deposited n-ZnO and p-ZnO thin films are investigated. An efficient p-n homojunction has been fabricated using the optimum p-ZnO:(P,N) and n-ZnO:Al layers. The current-voltage (I-V) characteristics show typical rectifying characteristics of p-n junction with a low turn on voltage. Electroluminescence (EL) studies reveals the fabricated p-n homojunction diodes exhibits strong emission features in ultra-violet (UV) region around 378 nm.

  9. Luminescence spectroscopy from the vacuum ultra-violet to the visible for Er 3+ and Tm 3+ in complex fluoride crystals

    Science.gov (United States)

    Khaidukov, N. M.; Lam, S. K.; Lo, D.; Makhov, V. N.; Suetin, N. V.

    2002-05-01

    Spectra and decay kinetics of luminescence from several complex fluorides of alkali elements and yttrium or gadolinium doped with Er 3+ or Tm 3+ have been studied in the vacuum ultra-violet (VUV), ultra-violet (UV) and visible spectral ranges under excitation by the 157 nm radiation from a pulsed molecular F 2-laser. It has been found that yttrium crystals have intense VUV luminescence due to interconfiguration 5d-4f transitions in the rare earth ions. On the other hand, the 5d-4f luminescence from Er 3+ or Tm 3+ in gadolinium crystals is completely absent and the nonradiative decay as a result of cross-relaxation is the dominant decay channel from the 5d level of the doping rare earth ion in these crystals. This process leads to complete conversion of absorbed VUV radiation into the lower energy part of the spectrum. These gadolinium fluorides appear to be promising materials for VUV-excited phosphors with high-quantum efficiency.

  10. Numerical study of extreme-ultra-violet generated plasmas in hydrogen

    OpenAIRE

    Astakhov, Dmitry

    2016-01-01

    In this thesis, we present the development and study a numerical model of EUV-induced plasma. Understanding of behavior of low pressure low density plasmas is of industrial relevance, because of their potential use for on-line removal of different forms of contaminations from multilayer mirrors, which will help increase the throughput of EUV lithography. The model is 2D axially symmetric particle-in-cell code, hence it allows the full geometry of an axially symmetric chamber to be taken into...

  11. Counter-facing plasma guns for efficient extreme ultra-violet plasma light source

    Directory of Open Access Journals (Sweden)

    Kuroda Yusuke

    2013-11-01

    Full Text Available A plasma focus system composed of a pair of counter-facing coaxial guns was proposed as a long-pulse and/or repetitive high energy density plasma source. We applied Li as the source of plasma for improvement of the conversion efficiency, the spectral purity, and the repetition capability. For operation of the system with ideal counter-facing plasma focus mode, we changed the system from simple coaxial geometry to a multi-channel configuration. We applied a laser trigger to make synchronous multi-channel discharges with low jitter. The results indicated that the configuration is promising to make a high energy density plasma with high spectral efficiency.

  12. Sub-50 nm metrology on extreme ultra violet chemically amplified resist--A systematic assessment.

    Science.gov (United States)

    Maas, D J; Fliervoet, T; Herfst, R; van Veldhoven, E; Meessen, J; Vaenkatesan, V; Sadeghian, H

    2015-10-01

    With lithographic patterning dimensions decreasing well below 50 nm, it is of high importance to understand metrology at such small scales. This paper presents results obtained from dense arrays of contact holes (CHs) with various Critical Dimension (CD) between 15 and 50 nm, as patterned in a chemically amplified resist using an ASML EUV scanner and measured at ASML and TNO. To determine the differences between various (local) CD metrology techniques, we conducted an experiment using optical scatterometry, CD-Scanning Electron Microscopy (CD-SEM), Helium ion Microscopy (HIM), and Atomic Force Microscopy (AFM). CD-SEM requires advanced beam scan strategies to mitigate sample charging; the other tools did not need that. We discuss the observed main similarities and differences between the various techniques. To this end, we assessed the spatial frequency content in the raw images for SEM, HIM, and AFM. HIM and AFM resolve the highest spatial frequencies, which are attributed to the more localized probe-sample interaction for these techniques. Furthermore, the SEM, HIM, and AFM waveforms are analyzed in detail. All techniques show good mutual correlation, albeit the reported CD values systematically differ significantly. HIM systematically reports a 25% higher CD uniformity number than CD-SEM for the same arrays of CHs, probably because HIM has a higher resolution than the CD-SEM used in this assessment. A significant speed boost for HIM and AFM is required before these techniques are to serve the demanding industrial metrology applications like optical critical dimension and CD-SEM do nowadays.

  13. Numerical study of extreme-ultra-violet generated plasmas in hydrogen

    NARCIS (Netherlands)

    Astakhov, Dmitry

    2016-01-01

    In this thesis, we present the development and study a numerical model of EUV-induced plasma. Understanding of behavior of low pressure low density plasmas is of industrial relevance, because of their potential use for on-line removal of different forms of contaminations from multilayer mirrors, whi

  14. Counter-facing plasma guns for efficient extreme ultra-violet plasma light source

    Science.gov (United States)

    Kuroda, Yusuke; Yamamoto, Akiko; Kuwabara, Hajime; Nakajima, Mitsuo; Kawamura, Tohru; Horioka, Kazuhiko

    2013-11-01

    A plasma focus system composed of a pair of counter-facing coaxial guns was proposed as a long-pulse and/or repetitive high energy density plasma source. We applied Li as the source of plasma for improvement of the conversion efficiency, the spectral purity, and the repetition capability. For operation of the system with ideal counter-facing plasma focus mode, we changed the system from simple coaxial geometry to a multi-channel configuration. We applied a laser trigger to make synchronous multi-channel discharges with low jitter. The results indicated that the configuration is promising to make a high energy density plasma with high spectral efficiency.

  15. Parametric Evaluation of an Innovative Ultra-Violet PhotocatalyticOxidation (UVPCO) Air Cleaning Technology for Indoor Applications

    Energy Technology Data Exchange (ETDEWEB)

    Hodgson, Alfred T.; Sullivan, Douglas P.; Fisk, William J.

    2005-10-31

    An innovative Ultra-Violet Photocatalytic Oxidation (UVPCO) air cleaning technology employing a semitransparent catalyst coated on a semitransparent polymer substrate was evaluated to determine its effectiveness for treating mixtures of volatile organic compounds (VOCs) representative of indoor environments at low, indoor-relevant concentration levels. The experimental UVPCO contained four 30 by 30-cm honeycomb monoliths irradiated with nine UVA lamps arranged in three banks. A parametric evaluation of the effects of monolith thickness, air flow rate through the device, UV power, and reactant concentrations in inlet air was conducted for the purpose of suggesting design improvements. The UVPCO was challenged with three mixtures of VOCs. A synthetic office mixture contained 27 VOCs commonly measured in office buildings. A building product mixture was created by combining sources including painted wallboard, composite wood products, carpet systems, and vinyl flooring. The third mixture contained formaldehyde and acetaldehyde. Steady state concentrations were produced in a classroom laboratory or a 20-m{sup 3} chamber. Air was drawn through the UVPCO, and single-pass conversion efficiencies were measured from replicate samples collected upstream and downstream of the reactor. Thirteen experiments were conducted in total. In this UVPCO employing a semitransparent monolith design, an increase in monolith thickness is expected to result in general increases in both reaction efficiencies and absolute reaction rates for VOCs oxidized by photocatalysis. The thickness of individual monolith panels was varied between 1.2 and 5 cm (5 to 20 cm total thickness) in experiments with the office mixture. VOC reaction efficiencies and rates increased with monolith thickness. However, the analysis of the relationship was confounded by high reaction efficiencies in all configurations for a number of compounds. These reaction efficiencies approached or exceeded 90% for alcohols, glycol

  16. Neuromuscular consequences of an extreme mountain ultra-marathon.

    Directory of Open Access Journals (Sweden)

    Guillaume Y Millet

    Full Text Available We investigated the physiological consequences of one of the most extreme exercises realized by humans in race conditions: a 166-km mountain ultra-marathon (MUM with 9500 m of positive and negative elevation change. For this purpose, (i the fatigue induced by the MUM and (ii the recovery processes over two weeks were assessed. Evaluation of neuromuscular function (NMF and blood markers of muscle damage and inflammation were performed before and immediately following (n = 22, and 2, 5, 9 and 16 days after the MUM (n = 11 in experienced ultra-marathon runners. Large maximal voluntary contraction decreases occurred after MUM (-35% [95% CI: -28 to -42%] and -39% [95% CI: -32 to -46%] for KE and PF, respectively, with alteration of maximal voluntary activation, mainly for KE (-19% [95% CI: -7 to -32%]. Significant modifications in markers of muscle damage and inflammation were observed after the MUM as suggested by the large changes in creatine kinase (from 144 ± 94 to 13,633 ± 12,626 UI L(-1, myoglobin (from 32 ± 22 to 1,432 ± 1,209 µg L(-1, and C-Reactive Protein (from <2.0 to 37.7 ± 26.5 mg L(-1. Moderate to large reductions in maximal compound muscle action potential amplitude, high-frequency doublet force, and low frequency fatigue (index of excitation-contraction coupling alteration were also observed for both muscle groups. Sixteen days after MUM, NMF had returned to initial values, with most of the recovery process occurring within 9 days of the race. These findings suggest that the large alterations in NMF after an ultra-marathon race are multi-factorial, including failure of excitation-contraction coupling, which has never been described after prolonged running. It is also concluded that as early as two weeks after such an extreme running exercise, maximal force capacities have returned to baseline.

  17. The relation between radio flux density and ionizing ultra-violet flux for HII regions and supernova remnants in the Large Magellanic cloud

    Directory of Open Access Journals (Sweden)

    Filipović M.D.

    2003-01-01

    Full Text Available We present a comparison between the Parkes radio surveys (Filipović et al 1995 and Vacuum Ultra-Violet (VUV surveys (Smith et al. 1987 of the Large Magellanic Clouds (LMC. We have found 72 sources in common in the LMC which are known HII regions (52 and supernova remnants (SNRs (19. Some of these radio sources are associated with two or more UV stellar associations. A comparison of the radio flux densities and ionizing UV flux for HII regions shows a very good correlation, as expected from theory. Many of the Magellanic Clouds (MCs SNRs are embedded in HII regions, so there is also a relation between radio and UV which we attribute to the surrounding HII regions.

  18. Ultra-violet absorption induced modifications in bulk and nanoscale electrical transport properties of Al-doped ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Mohit; Basu, Tanmoy; Som, Tapobrata, E-mail: tsom@iopb.res.in [SUNAG Laboratory, Institute of Physics, Sachivalaya Marg, Bhubaneswar 751 005 (India)

    2015-08-07

    Using conductive atomic force microscopy and Kelvin probe force microscopy, we study local electrical transport properties in aluminum-doped zinc oxide (ZnO:Al or AZO) thin films. Current mapping shows a spatial variation in conductivity which corroborates well with the local mapping of donor concentration (∼10{sup 20 }cm{sup −3}). In addition, a strong enhancement in the local current at grains is observed after exposing the film to ultra-violet (UV) light which is attributed to persistent photocurrent. Further, it is shown that UV absorption gives a smooth conduction in AZO film which in turn gives rise to an improvement in the bulk photoresponsivity of an n-AZO/p-Si heterojunction diode. This finding is in contrast to the belief that UV absorption in an AZO layer leads to an optical loss for the underneath absorbing layer of a heterojunction solar cell.

  19. Ultra-violet absorption induced modifications in bulk and nanoscale electrical transport properties of Al-doped ZnO thin films

    Science.gov (United States)

    Kumar, Mohit; Basu, Tanmoy; Som, Tapobrata

    2015-08-01

    Using conductive atomic force microscopy and Kelvin probe force microscopy, we study local electrical transport properties in aluminum-doped zinc oxide (ZnO:Al or AZO) thin films. Current mapping shows a spatial variation in conductivity which corroborates well with the local mapping of donor concentration (˜1020 cm-3). In addition, a strong enhancement in the local current at grains is observed after exposing the film to ultra-violet (UV) light which is attributed to persistent photocurrent. Further, it is shown that UV absorption gives a smooth conduction in AZO film which in turn gives rise to an improvement in the bulk photoresponsivity of an n-AZO/p-Si heterojunction diode. This finding is in contrast to the belief that UV absorption in an AZO layer leads to an optical loss for the underneath absorbing layer of a heterojunction solar cell.

  20. Effects of ultra-violet ray and aqueous environment on deformation behavior of spider threads; Kumoito no henkei kyodo ni oyobosu hikari oyobi mizu kankyo no eikyo

    Energy Technology Data Exchange (ETDEWEB)

    Kitagawa, M.; Katsumi, S. [Kanazawa University, Ishikawa (Japan). Faculty of Engineering; Wako, Y. [Hachinohe Institute of Technology, Aomori (Japan). Laboratory of Food Technology

    1998-01-15

    As a series of the studies on the mechanical properties of spider threads, the effects of ultra- violet rays (UV) and water was investigated using drag lines of Nephila clavata (Jorougumo) and capture threads of Argiope amoena (Koganegumo). It was shown for the effect of water that (1) the drag line was contracted as soon as immersed in water (super contraction), while the capture thread was not so contracted and the viscid droplets attached to it were dissolved in water, and (2) the super contracted drag fine behaved like a capture thread with a j shaped load-draw ratio curve. For the effect of UV, it was found that (1) the degradation due to UV irradiation with short wave length was accelerated more than that with long one and (2) the degree of degradation for each wave length was governed by the integrated irradiation energy of UV. 9 refs., 8 figs.

  1. Characterization and error analysis of an operational retrieval algorithm for estimating column ozone and aerosol properties from ground-based ultra-violet irradiance measurements

    Science.gov (United States)

    Taylor, Thomas E.; L'Ecuyer, Tristan; Slusser, James; Stephens, Graeme; Krotkov, Nick; Davis, John; Goering, Christian

    2005-08-01

    Extensive sensitivity and error characteristics of a recently developed optimal estimation retrieval algorithm which simultaneously determines aerosol optical depth (AOD), aerosol single scatter albedo (SSA) and total ozone column (TOC) from ultra-violet irradiances are described. The algorithm inverts measured diffuse and direct irradiances at 7 channels in the UV spectral range obtained from the United States Department of Agriculture's (USDA) UV-B Monitoring and Research Program's (UVMRP) network of 33 ground-based UV-MFRSR instruments to produce aerosol optical properties and TOC at all seven wavelengths. Sensitivity studies of the Tropospheric Ultra-violet/Visible (TUV) radiative transfer model performed for various operating modes (Delta-Eddington versus n-stream Discrete Ordinate) over domains of AOD, SSA, TOC, asymmetry parameter and surface albedo show that the solutions are well constrained. Realistic input error budgets and diagnostic and error outputs from the retrieval are analyzed to demonstrate the atmospheric conditions under which the retrieval provides useful and significant results. After optimizing the algorithm for the USDA site in Panther Junction, Texas the retrieval algorithm was run on a cloud screened set of irradiance measurements for the month of May 2003. Comparisons to independently derived AOD's are favorable with root mean square (RMS) differences of about 3% to 7% at 300nm and less than 1% at 368nm, on May 12 and 22, 2003. This retrieval method will be used to build an aerosol climatology and provide ground-truthing of satellite measurements by running it operationally on the USDA UV network database.

  2. Comparison of vacuum ultra-violet emission of Ar/CF4 and Ar/CF3I capacitively coupled plasmas

    Science.gov (United States)

    Zotovich, A.; Proshina, O.; el Otell, Z.; Lopaev, D.; Rakhimova, T.; Rakhimov, A.; de Marneffe, J.-F.; Baklanov, M. R.

    2016-10-01

    Spectra in the vacuum-ultra violet range (VUV, 30 nm-200 nm) as well as in the ultra-violet(UV) and visible ranges (UV+vis, 200 nm-800 nm) were measured from Ar/CF3I and Ar/CF4 discharges. The discharges were generated in an industrial 300 mm capacitively coupled plasma source with 27 MHz radio-frequency power. It was seen that the measured spectra were strongly modified. This is mainly due to absorption, especially by CF3I, and Ar self-trapping along the line of sight, towards the detector and in the plasma itself. The estimated unabsorbed VUV spectra were revealed from the spectra of mixtures with low fluorocarbon gas content by means of normalization with unabsorbed I* emission, at 206 nm, and CF2\\ast band (1B1(0,v‧,0){{\\to}1} A1(0,{{\\text{v}}\\prime \\prime} ,0)) emission between 230 nm and 430 nm. Absolute fluences of UV CF2\\ast emission were derived using hybrid 1-dimensional (1D) particle-in-cell (PIC) Monte-Carlo (MC) model calculations. Absolute calibration of the VUV emission was performed using these calculated values from the model, which has never been done previously for real etch conditions in an industrial chamber. It was seen that the argon resonant lines play a significant role in the VUV spectra. These lines are dominant in the case of etching recipes close to the standard ones. The restored unabsorbed spectra confirm that replacement of conventional CF4 etchant gas with CF3I in low-k etching recipes leads to an increase in the overall VUV emission intensity. However, emission from Ar exhibited the most intense peaks. Damage to low-k SiCOH glasses by the estimated VUV was calculated for blanket samples with pristine k-value of 2.2. The calculations were then compared with Fourier transform infrared (FTIR) data for samples exposed to the similar experimental conditions in the same reactor. It was shown that Ar emission plays the most significant role in VUV-induced damage.

  3. Generation and characterization of 2.2 W-level 318.6 nm narrow-linewidth ultra-violet laser

    CERN Document Server

    Wang, Jieying; He, Jun; Wang, Junmin

    2016-01-01

    We have demonstrated a high-power and narrow-linewidth ultra-violet (UV) laser system at 318.6 nm for single-step 6S1/2-nP (n=70~100) Rydberg excitation of cesium atoms. Based on commercial fiber lasers and efficient nonlinear frequency conversion technology, our system can generate 2.26 W UV laser output from cavity-enhanced second-harmonic generation (SHG) followed by sum-frequency generation (SFG) of two infrared lasers at 1560.5 nm and 1076.9 nm. The maximum doubling efficiency is 57.3%. The enhanced doubling cavity is actively stabilized by using the PDH modulation method, while the 637.2 nm laser is indirectly modulated through the SFG process which transfers modulation from the 1560.5 nm seed laser to the red laser. The typical UV laser power fluctuation is less than 0.87% over 30 minutes, and the continuously tunable range of the UV laser frequency is more than 6 GHz.

  4. Indian herb `Sanjeevani' (Selaginella bryopteris) can promote growth and protect against heat shock and apoptotic activities of ultra violet and oxidative stress

    Indian Academy of Sciences (India)

    Nand K Sah; Shyam Nandan P Singh; Sudhir Sahdev; Sharmishta Banerji; Vidyanath Jha; Zakir Khan; Seyed E Hasnain

    2005-09-01

    Selaginella bryopteris is a lithophyte with remarkable ressurection capabilities. It is full of medicinal properties, hence also known as ‘Sanjeevani’ (one that infuses life). For lack of credible scientific evidence the plant is not in active use as a medicinal herb. We provide scientific evidence for why S. bryopteris is known as ‘Sanjeevani’. The aqueous extract of S. bryopteris possesses growth-promoting activity as well as protective action against stress-induced cell death in a number of experimental cell systems including mammalian cells. Treatment of the cells in culture with 10% aqueous extract enhanced cell growth by about 41% in Sf9 cells and 78% in mammalian cells. Pre-treatment of cells with the Selaginella extract (SE) (1–2.5%) protected against oxidative stress (H2O2)-induced cell death. The killing potential of ultra violet (UV) was also significantly reduced when the cells were pre-treated with SE for 1 h. Thermal radiation suppressed cell growth by about 50%. Pre-treatment of cells with SE for 1 h afforded complete protection against heat-induced growth suppression. SE may possess anti-stress and antioxidant activities that could be responsible for the observed effects. Chemical analysis shows that SE contains hexoses and proteins. Taken together, S. bryopteris extract may help in stress-induced complications including those due to heat shock.

  5. Strongly Time-Variable Ultra-Violet Metal Line Emission from the Circum-Galactic Medium of High-Redshift Galaxies

    CERN Document Server

    Sravan, N; van de Voort, F; Keres, D; Muratov, A L; Hopkins, P F; Feldmann, R; Quataert, E; Murray, N

    2015-01-01

    We use cosmological simulations from the Feedback In Realistic Environments (FIRE) project, which implement a comprehensive set of stellar feedback processes, to study ultra-violet (UV) metal line emission from the circum-galactic medium of high-redshift (z = 2-4) galaxies. Our simulations cover the halo mass range Mh~2x10^11 - 8.5x10^12 Msun at z = 2, representative of Lyman break galaxies. Of the transitions we analyze, the low-ionization C III (977 A) and Si III (1207 A) emission lines are the most luminous, with C IV (1548 A) and Si IV (1394 A) also showing interesting spatially-extended structures that should be detectable by current and upcoming integral field spectrographs such as the Multi Unit Spectroscopic Explorer (MUSE) on the Very Large Telescope and Keck Cosmic Web Imager (KCWI). The more massive halos are on average more UV-luminous. The UV metal line emission from galactic halos in our simulations arises primarily from collisionally ionized gas and is strongly time variable, with peak-to-troug...

  6. ANALYSIS OF DIFFERENT BRANDS OF PARACETAMOL 500mg TABLETS USED IN MAIDUGURI, USING ULTRA VIOLET SPECTROPHOTOMETRIC AND HIGH PERFORMANCE LIQUID CHROMATOGRAPHIC (HPLC METHODS

    Directory of Open Access Journals (Sweden)

    Sani Ali. Audu

    2012-08-01

    Full Text Available The study involves quantitative analysis of eight (8 different brands (samples of Paracetamol 500mg tablets used in Maiduguri, using Ultra Violet Spectrophotometric and High Performance Liquid Chromatographic methods, in which the samples were dissolved in 0.1M NaOH and distilled water and their various absorbances determined at wavelength of 257nm and the HPLC method. The results obtained were compared with that of the standard. Percentage content and content in mg for each sample was calculated using the absorbances and peak areas of the samples and that of the standard, to see if it is within the specified limit by official books (90%-110% according to USP. The percentage content of the analyzed samples using HPLC method ranges from 51.04-103.84%, while using UV method it ranges from 50.19-109.1%, indicating none of the samples contains less than 50% of the active principle. It was observed that five (5 samples Neimeth, Unclu P, Palmol, Emzol, Fidson, out of the eight (8 Neimeth, Unclu P, Palmol, Emzol, Shekdol, Fidson, Nemel, Arenol, analysed meet up the USP specified limit. After the calculation of the standard deviation and coefficient of variation of the two methods used, which are 123.5 and 27.7% respectively for UV method and 82.67 and 20.4% respectively for HPLC method, it was also observed that the HPLC method is more suitable for such kind of studies than the UV method,

  7. Warm Dark Matter via Ultra-Violet Freeze-In: Reheating Temperature and Non-Thermal Distribution for Fermionic Higgs Portal Dark Matter

    CERN Document Server

    McDonald, John

    2015-01-01

    Warm dark matter (WDM) of order keV mass may be able to resolve the disagreement between structure formation in cold dark matter simulations and observations. The detailed properties of WDM will depend upon its energy distribution, in particular how it deviates from the thermal distribution usually assumed in WDM simulations. Here we focus on WDM production via the Ultra-Violet (UV) freeze-in mechanism, for the case of fermionic Higgs portal dark matter $\\psi$ produced the portal interaction $\\overline{\\psi}\\psi H^{\\dagger}H/\\Lambda$. We show that the reheating temperature must satisfy $T_{R} \\gtrsim 0.3 $ TeV in order to account for the observed dark matter density when $m_{\\psi} \\approx 2 $ keV, where the lower bound on $T_{R}$ corresponds to the limit where the fermion mass is entirely due to electroweak symmetry breaking via the portal interaction. The corresponding bound on the interaction scale is $\\Lambda \\gtrsim 1.5 \\times 10^{10}$ GeV. We introduce a new method to simplify the computation of the non-...

  8. Sub-mm Scale Fiber Guided Deep/Vacuum Ultra-Violet Optical Source for Trapped Mercury Ion Clocks

    Science.gov (United States)

    Yi, Lin; Burt, Eric A.; Huang, Shouhua; Tjoelker, Robert L.

    2013-01-01

    We demonstrate the functionality of a mercury capillary lamp with a diameter in the sub-mm range and deep ultraviolet (DUV)/ vacuum ultraviolet (VUV) radiation delivery via an optical fiber integrated with the capillary. DUV spectrum control is observed by varying the fabrication parameters such as buffer gas type and pressure, capillary diameter, electrical resonator design, and temperature. We also show spectroscopic data of the 199Hg+ hyper-fine transition at 40.5GHz when applying the above fiber optical design. We present efforts toward micro-plasma generation in hollow-core photonic crystal fiber with related optical design and theoretical estimations. This new approach towards a more practical DUV optical interface could benefit trapped ion clock developments for future ultra-stable frequency reference and time-keeping applications.

  9. Sub-mm Scale Fiber Guided Deep/Vacuum Ultra-Violet Optical Source for Trapped Mercury Ion Clocks

    Science.gov (United States)

    Yi, Lin; Burt, Eric A.; Huang, Shouhua; Tjoelker, Robert L.

    2013-01-01

    We demonstrate the functionality of a mercury capillary lamp with a diameter in the sub-mm range and deep ultraviolet (DUV)/ vacuum ultraviolet (VUV) radiation delivery via an optical fiber integrated with the capillary. DUV spectrum control is observed by varying the fabrication parameters such as buffer gas type and pressure, capillary diameter, electrical resonator design, and temperature. We also show spectroscopic data of the 199Hg+ hyper-fine transition at 40.5GHz when applying the above fiber optical design. We present efforts toward micro-plasma generation in hollow-core photonic crystal fiber with related optical design and theoretical estimations. This new approach towards a more practical DUV optical interface could benefit trapped ion clock developments for future ultra-stable frequency reference and time-keeping applications.

  10. Eye injuries in the extreme environment ultra-marathon runner.

    Science.gov (United States)

    Cope, Thomas Adam; Kropelnicki, Anna

    2015-06-02

    We present the case of an ultra-marathon runner who developed a painful irritated eye due to prolonged exposure to high wind speed and sub-zero temperatures causing transient freezing and subsequent abrasion of the cornea. We recommend that all ultra-marathon runners racing in windy or exposed conditions should wear wrap-around eye protection or goggles. If runners present to checkpoints or after the race to primary care or the emergency department with ocular pain, corneal freezing and abrasions should be considered. Management should include ocular examination and withdrawing the runner from harmful conditions.

  11. Simultaneous Determination of Six Benzodiazepines in Spiked Soft Drinks by High Performance Liquid Chromatography with Ultra Violet Detection (HPLC-UV)

    Science.gov (United States)

    Soltaninejad, Kambiz; Karimi, Mohammad; Nateghi, Alireza; Daraei, Bahram

    2016-01-01

    A high performance liquid chromatographic method with ultra violet detection for simultaneous analysis of six benzodiazepines (BZDs) (chlordiazepoxide, diazepam, clonazepam, midazolam , flurazpam, and lorazepam) has been developed for forensic screening of adulterated non-alcoholic drinks. Samples were analyzed after a simple procedure for preparation using pH adjustment and filtering. Isocratic elution on a C18 column (250mm × 4.6 mm, 5μm) in the temperature 45ºC with a mobile phase consisting of 15mM phosphate buffer: methanol (50:50 v/v) at a flow rate 1.4 mL/min has been done. The column eluent was monitored with a UV detector at 245 nm. This allowed a rapid detection and identification as well as quantization of the eluting peaks. Calibration curves for all drugs in the range of 0.5- 10 µg/ mL that all the linear regression and has more than 0.996. Recovery rates for the BZDs were in the range 93.7- 108.7%. The limits of detection were calculated between 0.01- 0.02 µg/ mL. Also, the limits of quantification were 0.03- 0.05 µg/mL. Within-day and between -day coefficient of variation for all BZDs at all concentrations in the range of 0.45 - 7.69 % was calculated. The procedure can provide a simple, sensitive and fast method for the screening of six BZDs in adulterated soft drinks in forensic analysis. PMID:27642316

  12. Oxygen vacancy induced photoluminescence properties and enhanced photocatalytic activity of ferromagnetic ZrO{sub 2} nanostructures on methylene blue dye under ultra-violet radiation

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Sachin; Ojha, Animesh K., E-mail: animesh@mnnit.ac.in

    2015-09-25

    Highlights: • Room temperature ferromagnetism (RTFM) is found in ZrO{sub 2} nanostructures. • Oxygen vacancies are found to be the possible reason for the presence of RTFM. • The presence of oxygen vacancies are confirmed by photoluminescence spectra. • Enhanced photocatalytic activity of ZrO{sub 2} has been observed for MB dye. • Possible photodegradation mechanism of MB dye has been proposed. - Abstract: Room temperature ferromagnetic (RTFM) ZrO{sub 2} nanostructures with tetragonal (t-ZrO{sub 2}) and monoclinic (m-ZrO{sub 2}) phases were synthesized by sol–gel method. The photoluminescence (PL) feature of the synthesized samples was investigated using 300 nm excitation wavelength. The decrease of saturation magnetization (Ms) and intensity of emission band at higher calcinations temperature is attributed to the reduction of density of oxygen vacancies in the ZrO{sub 2} matrix. The variation of Ms with calcinations temperature follows the same trend as intensity of emission band varies. It further confirms that the presence of RTFM and decrease in emission band intensity is caused due change in density of oxygen vacancies with calcinations temperature. The photocatalytic activity of ZrO{sub 2} nanostructures has been investigated on methylene blue (MB) dye as function of particle size under ultra-violet (UV) radiation with 365 nm wavelength. The ZrO{sub 2} nanostructures with smaller particle size are found to be efficient for photodegradation of MB dye. Oxygen vacancies are found to be the main cause for enhanced photocatalytic activity of ZrO{sub 2} nanostructures.

  13. A Hot Companion to a Blue Straggler in NGC 188 as Revealed by the Ultra-Violet Imaging Telescope (UVIT) on ASTROSAT

    Science.gov (United States)

    Subramaniam, Annapurni; Sindhu, N.; Tandon, S. N.; Kameswara Rao, N.; Postma, J.; Côté, Patrick; Hutchings, J. B.; Ghosh, S. K.; George, K.; Girish, V.; Mohan, R.; Murthy, J.; Sankarasubramanian, K.; Stalin, C. S.; Sutaria, F.; Mondal, C.; Sahu, S.

    2016-12-01

    We present early results from the Ultra-Violet Imaging Telescope (UVIT) on board the ASTROSAT observatory. We report the discovery of a hot companion associated with one of the blue straggler stars (BSSs) in the old open cluster, NGC 188. Using fluxes measured in four filters in UVIT’s far-UV (FUV) channel, and two filters in the near-UV (NUV) channel, we have constructed the spectral energy distribution (SED) of the star WOCS-5885, after combining with flux measurements from GALEX, Ultraviolet Imaging Telescope, Ultraviolet Optical Telescope, SPITZER, WISE, and several ground-based facilities. The resulting SED spans a wavelength range of 0.15 μm to 7.8 μm. This object is found to be one of the brightest FUV sources in the cluster. An analysis of the SED reveals the presence of two components. The cooler component is found to have a temperature of 6000 ± 150 K, confirming that it is a BSS. Assuming it to be a main-sequence star, we estimate its mass to be ˜1.1-1.2 M ⊙. The hotter component, with an estimated temperature of 17,000 ± 500 K, has a radius of ˜ 0.6 R ⊙ and L ˜30 L ⊙. Bigger and more luminous than a white dwarf, yet cooler than a sub-dwarf, we speculate that it is a post-AGB/HB star that has recently transferred its mass to the BSS, which is known to be a rapid rotator. This binary system, which is the first BSS with a post-AGB/HB companion identified in an open cluster, is an ideal laboratory to study the process of BSS formation via mass transfer.

  14. Simultaneous Determination of Six Benzodiazepines in Spiked Soft Drinks by High Performance Liquid Chromatography with Ultra Violet Detection (HPLC-UV).

    Science.gov (United States)

    Soltaninejad, Kambiz; Karimi, Mohammad; Nateghi, Alireza; Daraei, Bahram

    2016-01-01

    A high performance liquid chromatographic method with ultra violet detection for simultaneous analysis of six benzodiazepines (BZDs) (chlordiazepoxide, diazepam, clonazepam, midazolam , flurazpam, and lorazepam) has been developed for forensic screening of adulterated non-alcoholic drinks. Samples were analyzed after a simple procedure for preparation using pH adjustment and filtering. Isocratic elution on a C18 column (250mm × 4.6 mm, 5μm) in the temperature 45ºC with a mobile phase consisting of 15mM phosphate buffer: methanol (50:50 v/v) at a flow rate 1.4 mL/min has been done. The column eluent was monitored with a UV detector at 245 nm. This allowed a rapid detection and identification as well as quantization of the eluting peaks. Calibration curves for all drugs in the range of 0.5- 10 µg/ mL that all the linear regression and has more than 0.996. Recovery rates for the BZDs were in the range 93.7- 108.7%. The limits of detection were calculated between 0.01- 0.02 µg/ mL. Also, the limits of quantification were 0.03- 0.05 µg/mL. Within-day and between -day coefficient of variation for all BZDs at all concentrations in the range of 0.45 - 7.69 % was calculated. The procedure can provide a simple, sensitive and fast method for the screening of six BZDs in adulterated soft drinks in forensic analysis.

  15. An Oceanic Ultra-Violet Catastrophe, Wave-Particle Duality and a Strongly Nonlinear Concept for Geophysical Turbulence

    Directory of Open Access Journals (Sweden)

    Kurt L. Polzin

    2017-06-01

    Full Text Available There is no theoretical underpinning that successfully explains how turbulent mixing is fed by wave breaking associated with nonlinear wave-wave interactions in the background oceanic internal wavefield. We address this conundrum using one-dimensional ray tracing simulations to investigate interactions between high frequency internal waves and inertial oscillations in the extreme scale separated limit known as “Induced Diffusion”. Here, estimates of phase locking are used to define a resonant process (a resonant well and a non-resonant process that results in stochastic jumps. The small amplitude limit consists of jumps that are small compared to the scale of the resonant well. The ray tracing simulations are used to estimate the first and second moments of a wave packet’s vertical wavenumber as it evolves from an initial condition. These moments are compared with predictions obtained from the diffusive approximation to a self-consistent kinetic equation derived in the ‘Direct Interaction Approximation’. Results indicate that the first and second moments of the two systems evolve in a nearly identical manner when the inertial field has amplitudes an order of magnitude smaller than oceanic values. At realistic (oceanic amplitudes, though, the second moment estimated from the ray tracing simulations is inhibited. The transition is explained by the stochastic jumps obtaining the characteristic size of the resonant well. We interpret this transition as an adiabatic ‘saturation’ process which changes the nominal background wavefield from supporting no mixing to the point where that background wavefield defines the normalization for oceanic mixing models.

  16. Evaluation of Ultra-Violet Photocatalytic Oxidation (UVPCO) forIndoor Air Applications: Conversion of Volatile Organic Compounds at LowPart-per-Billion Concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Hodgson, Alfred T.; Sullivan, Douglas P.; Fisk, William J.

    2005-09-30

    Efficient removal of indoor generated airborne particles and volatile organic compounds (VOCs) in office buildings and other large buildings may allow for a reduction in outdoor air supply rates with concomitant energy savings while still maintaining acceptable indoor air quality in these buildings. Ultra-Violet Photocatalytic Oxidation (UVPCO) air cleaners have the potential to achieve the necessary reductions in indoor VOC concentrations at relatively low cost. In this study, laboratory experiments were conducted with a scaled, prototype UVPCO device designed for use in a duct system. The experimental UVPCO contained two 30 by 30-cm honeycomb monoliths coated with titanium dioxide and 3% by weight tungsten oxide. The monoliths were irradiated with 12 UVC lamps arranged in four banks. The UVPCO was challenged with four mixtures of VOCs typical of mixtures encountered in indoor air. A synthetic office mixture contained 27 VOCs commonly measured in office buildings. A cleaning product mixture contained three cleaning products with high market shares. A building product mixture was created by combining sources including painted wallboard, composite wood products, carpet systems, and vinyl flooring. A fourth mixture contained formaldehyde and acetaldehyde. Steady-state concentrations were produced in a classroom laboratory or a 20-m{sup 3} environmental chamber. Air was drawn through the UVPCO, and single pass conversion efficiencies were measured from replicate air samples collected upstream and downstream of the reactor section. Concentrations of the mixtures were manipulated, with concentrations of individual VOCs mostly maintained below 10 ppb. Device flow rates were varied between 165 and 580 m{sup 3}/h. Production of formaldehyde, acetaldehyde, acetone, formic acid, and acetic acid as reaction products was investigated. Conversion efficiency data were generated for 48 individual VOCs or groups of closely related compounds. Alcohols and glycol ethers were the

  17. Deciphering the structure of isomeric oligosaccharides in a complex mixture by tandem mass spectrometry: Photon activation with vacuum ultra-violet brings unique information and enables definitive structure assignment

    Energy Technology Data Exchange (ETDEWEB)

    Ropartz, David, E-mail: David.Ropartz@nantes.inra.fr [INRA, UR1268 Biopolymers Interactions Assemblies, F-44316 Nantes (France); Lemoine, Jérôme [Institut des Sciences Analytiques, UMR 5280, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Giuliani, Alexandre [Synchrotron SOLEIL, L’Orme des Merisiers, F-91190 Gif-sur-Yvette (France); UAR 1008 CEPIA, INRA, F-44316 Nantes (France); Bittebière, Yann [INRA, UR1268 Biopolymers Interactions Assemblies, F-44316 Nantes (France); Enjalbert, Quentin [Institut des Sciences Analytiques, UMR 5280, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Antoine, Rodolphe; Dugourd, Philippe [Institut Lumière Matière, UMR5306, Université Lyon 1-CNRS, Université de Lyon, F-69622 Villeurbanne cedex (France); Ralet, Marie-Christine; Rogniaux, Hélène [INRA, UR1268 Biopolymers Interactions Assemblies, F-44316 Nantes (France)

    2014-01-07

    Graphical abstract: -- Highlights: •A complex mixture of methylated oligogalacturonans was fractionated by IP-RP-UHPLC. •Synchrotron-radiation in VUV range was used as an activation process for tandem MS. •VUV activation brought rich structural information compared to LE-CAD. •Resolution of more than 35 structures, including isomers, was successfully completed. -- Abstract: Carbohydrates have a wide variety of structures whose complexity and heterogeneity challenge the field of analytical chemistry. Tandem mass spectrometry, with its remarkable sensitivity and high information content, provides key advantages to addressing the structural elucidation of polysaccharides. Yet, classical fragmentation by collision-activated dissociation (CAD) in many cases fails to reach a comprehensive structural determination, especially when isomers have to be differentiated. In this work, for the first time, vacuum ultra-violet (VUV) synchrotron radiation is used as the activation process in tandem mass spectrometry of large oligosaccharides. Compared to low energy CAD (LE-CAD), photon activated dissociation brought more straightforward and valuable structural information. The outstanding feature was that complete series of informative ions were produced, with only minor neutral losses. Moreover, systematic fragmentation rules could be drawn thus facilitating the definitive assignments of fragment identities. As a result, most of the structures present in a complex mixture of oligogalacturonans could be comprehensively resolved, including many isomers differing in the position of methyl groups along the galacturonic acid backbone.

  18. Depth-resolved ultra-violet spectroscopic photo current-voltage measurements for the analysis of AlGaN/GaN high electron mobility transistor epilayer deposited on Si

    Energy Technology Data Exchange (ETDEWEB)

    Ozden, Burcu; Yang, Chungman; Tong, Fei; Khanal, Min P.; Mirkhani, Vahid; Sk, Mobbassar Hassan; Ahyi, Ayayi Claude; Park, Minseo, E-mail: park@physics.auburn.edu [Department of Physics, Auburn University, Auburn, Alabama 36849 (United States)

    2014-10-27

    We have demonstrated that the depth-dependent defect distribution of the deep level traps in the AlGaN/GaN high electron mobility transistor (HEMT) epi-structures can be analyzed by using the depth-resolved ultra-violet (UV) spectroscopic photo current-voltage (IV) (DR-UV-SPIV). It is of great importance to analyze deep level defects in the AlGaN/GaN HEMT structure, since it is recognized that deep level defects are the main source for causing current collapse phenomena leading to reduced device reliability. The AlGaN/GaN HEMT epi-layers were grown on a 6 in. Si wafer by metal-organic chemical vapor deposition. The DR-UV-SPIV measurement was performed using a monochromatized UV light illumination from a Xe lamp. The key strength of the DR-UV-SPIV is its ability to provide information on the depth-dependent electrically active defect distribution along the epi-layer growth direction. The DR-UV-SPIV data showed variations in the depth-dependent defect distribution across the wafer. As a result, rapid feedback on the depth-dependent electrical homogeneity of the electrically active defect distribution in the AlGaN/GaN HEMT epi-structure grown on a Si wafer with minimal sample preparation can be elucidated from the DR-UV-SPIV in combination with our previously demonstrated spectroscopic photo-IV measurement with the sub-bandgap excitation.

  19. Scintillation properties of Nd{sup 3+}, Tm{sup 3+}, and Er{sup 3+} doped LuF{sub 3} scintillators in the vacuum ultra violet region

    Energy Technology Data Exchange (ETDEWEB)

    Yanagida, Takayuki, E-mail: yanagida@imr.tohoku.ac.jp [New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Kawaguchi, Noriaki [Tokuyama Corporation Ltd., Shibuya 3-chome, Shibuya-ku, Tokyo 150-8383 Japan (Japan); Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577 (Japan); Fukuda, Kentaro [Tokuyama Corporation Ltd., Shibuya 3-chome, Shibuya-ku, Tokyo 150-8383 Japan (Japan); Kurosawa, Shunsuke; Fujimoto, Yutaka; Futami, Yoshisuke; Yokota, Yuui [Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577 (Japan); Taniue, Kojiro [Department of Physics, Graduate School of Science, Kyoto University, Kitashirakawa-oiwakecho, Sakyo, Kyoto, 606-8502 (Japan); Sekiya, Hiroyuki [Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Hida, 506-1205 (Japan); Kubo, Hidetoshi [Department of Physics, Graduate School of Science, Kyoto University, Kitashirakawa-oiwakecho, Sakyo, Kyoto, 606-8502 (Japan); Yoshikawa, Akira [New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai, 980-8577 (Japan); Tanimori, Toru [Department of Physics, Graduate School of Science, Kyoto University, Kitashirakawa-oiwakecho, Sakyo, Kyoto, 606-8502 (Japan)

    2011-12-11

    In order to develop novel vacuum ultra violet (VUV) emitting scintillators, we grew Nd 0.5%, Tm 0.5%, and Er 0.5% doped LuF{sub 3} scintillators by the {mu}-pulling down method, because LuF{sub 3} has a very wide band gap and Nd{sup 3+}, Tm{sup 3+}, and Er{sup 3+} luminescence centers show fast and intense 5d-4f emission in VUV region. Transmittance and X-ray induced radioluminescence were studied in these three samples using our original spectrometer made by Bunkou-Keiki company. In the VUV region, transmittance of 20-60% was achieved for all the samples. The emission peaks appeared at approximately 180, 165, and 164 nm for Nd{sup 3+}, Tm{sup 3+}, and Er{sup 3+} doped LuF{sub 3}, respectively. Using PMT R8778 (Hamamatsu), we measured their light yields under {sup 241}Am {alpha}-ray excitation. Compared with Nd:LaF{sub 3} scintillator, which has 33 photoelectrons/5.5 MeV {alpha}, Nd:LuF{sub 3} and Tm:LuF{sub 3} showed 900{+-}90 and 170{+-}20 ph/5.5 MeV-{alpha}, respectively. Only for the Nd doped one, we can detect {sup 137}Cs 662 keV {gamma}-ray photoabsorption peak and the light yield of 1200{+-}120 ph/MeV was measured. We also investigated their decay time profiles by picosecond pulse X-ray equipped streak camera, and the main decay component of Nd:LuF{sub 3} turned out to be 7.63 ns.

  20. Prospects of hydroacoustic detection of ultra-high and extremely high energy cosmic neutrinos

    Science.gov (United States)

    Dedenko, L. G.; Karlik, Ya. S.; Learned, J. G.; Svet, V. D.; Zheleznykh, I. M.

    2001-07-01

    The prospects of construction of deep underwater neutrino telescopes in the world's oceans for the goals of ultra-high and super-high energy neutrino astrophysics (astronomy) using acoustic technologies are reviewed. The effective detection volume of the acoustic neutrino telescopes can be far greater than a cubic kilometer for extreme energies. In recent years, it was proposed that an existing hydroacoustic array of 2400 hydrophones in the Pacific Ocean near Kamchatka Peninsula could be used as a test base for an acoustic neutrino telescope SADCO (Sea-based Acoustic Detector of Cosmic Objects) which should be capable of detecting acoustic signals produced in water by the cosmic neutrinos with energies 1019-21 eV (e.g., topological defect neutrinos). We report on simulations of super-high energy electron-hadron and electron-photon cascades with the Landau-Pomeranchuk-Migdal effect taken into account. Acoustic signals emitted by neutrino-induced cascades with energies 1020-21 eV were calculated. The possibilities of using a converted hydroacoustic station MG-10 (MG-10M) of 132 hydrophones as a basic module for a deep water acoustic neutrino detector with the threshold detection energy 1015 eV in the Mediterranean Sea are analyzed (with the aim of searching for neutrinos with energies 1015-16 eV from Active Galactic Nuclei). .

  1. Atmospheric and Fog Effects on Ultra-Wide Band Radar Operating at Extremely High Frequencies.

    Science.gov (United States)

    Balal, Nezah; Pinhasi, Gad A; Pinhasi, Yosef

    2016-05-23

    The wide band at extremely high frequencies (EHF) above 30 GHz is applicable for high resolution directive radars, resolving the lack of free frequency bands within the lower part of the electromagnetic spectrum. Utilization of ultra-wideband signals in this EHF band is of interest, since it covers a relatively large spectrum, which is free of users, resulting in better resolution in both the longitudinal and transverse dimensions. Noting that frequencies in the millimeter band are subjected to high atmospheric attenuation and dispersion effects, a study of the degradation in the accuracy and resolution is presented. The fact that solid-state millimeter and sub-millimeter radiation sources are producing low power, the method of continuous-wave wideband frequency modulation becomes the natural technique for remote sensing and detection. Millimeter wave radars are used as complementary sensors for the detection of small radar cross-section objects under bad weather conditions, when small objects cannot be seen by optical cameras and infrared detectors. Theoretical analysis for the propagation of a wide "chirped" Frequency-Modulated Continuous-Wave (FMCW) radar signal in a dielectric medium is presented. It is shown that the frequency-dependent (complex) refractivity of the atmospheric medium causes distortions in the phase of the reflected signal, introducing noticeable errors in the longitudinal distance estimations, and at some frequencies may also degrade the resolution.

  2. Extremely stretchable and conductive water-repellent coatings for low-cost ultra-flexible electronics

    Science.gov (United States)

    Mates, Joseph E.; Bayer, Ilker S.; Palumbo, John M.; Carroll, Patrick J.; Megaridis, Constantine M.

    2015-11-01

    Rapid advances in modern electronics place ever-accelerating demands on innovation towards more robust and versatile functional components. In the flexible electronics domain, novel material solutions often involve creative uses of common materials to reduce cost, while maintaining uncompromised performance. Here we combine a commercially available paraffin wax-polyolefin thermoplastic blend (elastomer matrix binder) with bulk-produced carbon nanofibres (charge percolation network for electron transport, and for imparting nanoscale roughness) to fabricate adherent thin-film composite electrodes. The simple wet-based process produces composite films capable of sustained ultra-high strain (500%) with resilient electrical performance (resistances of the order of 101-102 Ω sq-1). The composites are also designed to be superhydrophobic for long-term corrosion protection, even maintaining extreme liquid repellency at severe strain. Comprised of inexpensive common materials applied in a single step, the present scalable approach eliminates manufacturing obstacles for commercially viable wearable electronics, flexible power storage devices and corrosion-resistant circuits.

  3. Classification of extremely red objects in the Hubble Ultra Deep Field

    Institute of Scientific and Technical Information of China (English)

    Guan-Wen Fang; Xu Kong; Min Wang

    2009-01-01

    We present a quantitative study of the classification of Extremely Red Objects (EROs). The analysis is based on the multi-band spatial-and ground-based observa-tions (HST/ACS-BViz, HST/NICMOS-JH, VLT-JHK) in the Hubble Ultra Deep Field (UDF). Over a total sky area of 5.50 arcmin2 in the UDF, we select 24 EROs with the color criterion (i-K)vega 3.9, corresponding to (I-K)vega 4.0, down to KVega = 22. We develop four methods to classify EROs into Old passively evolving Galaxies (OGs) and Dusty star-forming Galaxies (DGs), including (i-K) vs. (J-K) color diagram,spectral energy distribution fitting method, Spitzer MIPS 24μm image matching, and nonparametric measure of galaxy morphology, and found that the classification results from these methods agree well. Using these four classification methods, we classify our EROs sample into 60Gs and 8 DGs to KVega < 20.5, and 80Gs and 16 DGs to KVega < 22, respectively. The fraction of DGs increases from 8/14 at KVega < 20.5to 16/24 at Kvega < 22. To study the morphology of galaxies with its wavelength, we measure the central concentration and the Gini coefficient for the 24 EROs in our sample in HST/ACS-i, z and HST/NICMOS-J, H bands. We find that the morphological param-eters of galaxies in our sample depend on the wavelength of observation, which suggests that caution is necessary when comparing single wavelength band images of galaxies at a variety of redshifts.

  4. Ultra-Violet Induced Insulator Flashover

    Energy Technology Data Exchange (ETDEWEB)

    Javedani, J B; Houck, T L; Kelly, B T; Lahowe, D A; Shirk, M D; Goerz, D A

    2008-05-21

    Insulators are critical components in high-energy, pulsed power systems. It is known that the vacuum surface of the insulator will flashover when illuminated by ultraviolet (UV) radiation depending on the insulator material, insulator cone angle, applied voltage and insulator shot-history. A testbed comprised of an excimer laser (KrF, 248 nm, {approx} 2 MW/cm{sup 2}, 30 ns FWHM,), a vacuum chamber (low 1.0E-6 torr), and dc high voltage power supply (<60 kV) was assembled for insulator testing to measure the UV dose during a flashover event. Five in-house developed and calibrated fast D-Dot probes (>12 GHz, bandwidth) were embedded in the anode electrode underneath the insulator to determine the time of flashover with respect to UV arrival. A commercial energy meter were used to measure the UV fluence for each pulse. Four insulator materials High Density Polyethylene, Rexolite{reg_sign} 1400, Macor{trademark} and Mycalex with side-angles of 0, {+-}30, and {+-}45 degrees, 1.0 cm thick samples, were tested with a maximum UV fluence of 75 mJ/cm{sup 2} and at varying electrode charge (10 kV to 60 kV). This information clarified/corrected earlier published studies. A new phenomenon was observed related to the UV power level on flashover that as the UV pulse intensity was increased, the UV fluence on the insulator prior to flashover was also increased. This effect would bias the data towards higher minimum flashover fluence.

  5. Ultra-Low Power Extreme Environment Capable Avionics System-on-a-Chip Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Develop ultra-low-power, wide-temperature (-150° C to +250 ° C), digital System-on-a-Chip (SOC) ASIC technology in a high resolution, inherently rad-hard IBM...

  6. Etude de la variation de transmission optique dans l'UltraViolet du quartz "Nippon Silica Glass" après expositions à des rayonnements - Etude du système d'acquisition de données et du système de contrôle de Hautes Tensions appliquées aux chambres à fils du BARREL RICH de DELPHI

    CERN Document Server

    Delorme, Sophie

    1992-01-01

    Etude de la variation de transmission optique dans l'UltraViolet du quartz "Nippon Silica Glass" après expositions à des rayonnements - Etude du système d'acquisition de données et du système de contrôle de Hautes Tensions appliquées aux chambres à fils du BARREL RICH de DELPHI

  7. Observing Ultra High Energy Cosmic Particles from Space: SEUSO, the Super Extreme Universe Space Observatory Mission

    CERN Document Server

    Santangelo, Andrea

    2009-01-01

    The experimental search for ultra high energy cosmic messengers, from $E\\sim 10^{19}$ eV to beyond $E\\sim 10^{20}$ eV, at the very end of the known energy spectrum, constitutes an extraordinary opportunity to explore a largely unknown aspect of our universe. Key scientific goals are the identification of the sources of ultra high energy particles, the measurement of their spectra and the study of galactic and local intergalactic magnetic fields. Ultra high energy particles might, also, carry evidence of unknown physics or of exotic particles relics of the early universe. To meet this challenge a significant increase in the integrated exposure is required. This implies a new class of experiments with larger acceptances and good understanding of the systematic uncertainties. Space based observatories can reach the instantaneous aperture and the integrated exposure necessary to systematically explore the ultra high energy universe. In this paper, after briefly summarising the science case of the mission, we desc...

  8. Microscopic description of rotation: From ground states to the extremes of ultra-high spin

    CERN Document Server

    Afanasjev, A V

    2013-01-01

    Recent progress in the microscopic description of rotational properties within covariant density functional theory (CDFT) is presented. It is shown that it provides an accurate description of rotational bands both in the paired regime at low spin and in the unpaired regime at ultra-high spins. The predictive power of CDFT is verified by comparing the CDFT predictions for band crossing features in the $A\\geq 242$ actinides with new experimental data. In addition, possible role of the Coulomb antipairing effect for proton pairing is discussed.

  9. Extreme ultraviolet (EUV) source and ultra-high vacuum chamber for studying EUV-induced processes

    NARCIS (Netherlands)

    Dolgov, A.; Yakushev, O.; Abrikosov, A.; Snegirev, E.; Krivtsun, V.M.; Lee, C.J.; Bijkerk, F.

    2015-01-01

    An experimental setup that directly reproduces extreme ultraviolet (EUV) lithography relevant conditions for detailed component exposure tests is described. The EUV setup includes a pulsed plasma radiation source, operating at 13.5 nm; a debris mitigation system; collection and filtering optics; and

  10. Effects of radiation damping in extreme ultra-intense laser-plasma interaction

    Science.gov (United States)

    Pandit, Rishi; Sentoku, Yasuhiko

    2011-10-01

    Effects of the radiation damping in the interaction of extremely intense laser (>1022 W/cm2) with overdense plasma are studied via a relativistic collisional particle-in-cell simulation, PICLS1D. We had derived the Landau-Lifshitz equation, which is the first order term of the Lorentz-Dirac equation, and also derived the second order term as the first time and implemented in the code. The code had been tested in a single particle motion at the extreme intensity laser. It was found that the first order damping term is reasonable up to the intensity 1022 W/cm2, but the second oder term becomes not negligible and comparable to the first order term beyond 1023 W/cm2. The radiation damping model was introduced to a one- dimensional particle-in-cell code (PIC), and tested in the laser - plasma interaction at extreme intensity. The strong damping of hot electrons in high energy tail was demonstrated in PIC simulations. Hot electrons generated by such extreme-intense laser lights on the plasma get the relativistic energy with gamma factor >100, and lose energy strongly by emitting radiation. The second order term becomes comparable to the first order term when the laser intensity >1023 W/cm2. US DOE DE-PS02-08ER08-16 and DE-FC02-04ER54789.

  11. 21 CFR 73.2775 - Manganese violet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Manganese violet. 73.2775 Section 73.2775 Food and... ADDITIVES EXEMPT FROM CERTIFICATION Cosmetics § 73.2775 Manganese violet. (a) Identity. The color additive manganese violet is a violet pigment obtained by reacting phosphoric acid, ammonium...

  12. Study on Spectral Response beyond Cut off of Cs2Te Ultra Violet Photo Cathode%Cs2Te紫外光电阴极带外光谱响应研究

    Institute of Scientific and Technical Information of China (English)

    李晓峰; 姜云龙; 李靖雯; 姬明; 李金沙; 张勤东

    2015-01-01

    With the strong light as the input, the spectral response beyond cut off of the Cs2Te ultraviolet photo cathode is measured. The results show that the spectral response of the Cs2Te cathode beyond cut off is lower, and is several orders of magnitude lower than that within the cutoff. The peak sensitivity of within cutoff can be greater than 40mA/W, but the spectral response beyond cut off can be as low as 10-3mA/W order of magnitude at 550nm wavelength. The divergence of spectral response beyond cut off of Cs2Te ultraviolet photo cathode made with the same process is large. According to the test of three different visible light photo cathode, namely Na2KSb (Cs), K2CsSb and GaAs (Cs-O), it is proved that these three kinds of visible light photo cathode also have certain spectral response. The test data show that the spectral response beyond cut off is related to the size of the work function (positive electron affinity cathode) or the band gap (negative electron affinity cathode). The smaller the work function or the band gap is, the greater the spectral response beyond cut off. The spectral response beyond cut off is a common phenomenon for photo cathode. The reason is that the effect of multiphoton absorption, i.e. multiphoton effect. Because Cs2Te photo cathodes are present spectral response beyond cut off, thus, when solar blind image intensifier adopting Cs2Te photo cathodes is used in the strong sun light or straight to the sun's light, detected signal would be disturbed by the light of the sun, or by the image of the sun like. Thus solar blind image intensifier does not have the sun blind characteristic. In order to make the solar blind ultraviolet image intensifier fully equipped with solar blind characteristic, solar blind filter is needed. Combining solar blind filter with spectral response of Cs2Te cathode beyond cut off, solar blind image intensifier can achieve complete solar blind. So in the practical application of ultra violet detecting, the solar

  13. Effects of radiation damping in ultra-intense laser matter interaction at extreme intensity regime

    Science.gov (United States)

    Sentoku, Yasuhiko; Pandit, Rishi

    2011-10-01

    Effects of the radiation damping in the interaction of extremely intense laser (>1022 W/cm2) with metal targets are studied via a relativistic collisional particle- in-cell simulation, PICLS. We had introduced the Landau-Lifshitz equation, which is the first order term of the Lorentz-Dirac equation to PIC, and also derived the second order term to check its effect. We had implemented these damping terms in the two- dimensional PICLS code, and had studied the laser plasma interaction at >1022 W/cm2 intensities. Hot electrons generated by such extreme-intense laser lights on the target get the relativistic energy with relativistic Lorentz factor γ > 100 , and lose energy strongly by emitting radiations. Especially, we had studied the second term's effect in a comparison with the first order damping term, and found that the second term becomes comparable to the first order term when the laser intensity >1023 W/cm2. With the higher order term, the hot electrons with energies greater than 500 MeV are totally suppressed and hard them to go beyond that energy even increasing the laser intensity >1023 W/cm2. Supported by US DOE DE-PS02-08ER08-16 and DE-FC02-04ER54789.

  14. Extreme Mountain Ultra-Marathon Leads to Acute but Transient Increase in Cerebral Water Diffusivity and Plasma Biomarkers Levels Changes

    Science.gov (United States)

    Zanchi, Davide; Viallon, Magalie; Le Goff, Caroline; Millet, Grégoire P.; Giardini, Guido; Croisille, Pierre; Haller, Sven

    2017-01-01

    Background: Pioneer studies demonstrate the impact of extreme sport load on the human brain, leading to threatening conditions for athlete's health such as cerebral edema. The investigation of brain water diffusivity, allowing the measurement of the intercellular water and the assessment of cerebral edema, can give a great contribution to the investigation of the effects of extreme sports on the brain. We therefore assessed the effect of supra-physiological effort (extreme distance and elevation changes) in mountain ultra-marathons (MUMs) athletes combining for the first time brain magnetic resonance imaging (MRI) and blood parameters. Methods:This longitudinal study included 19 volunteers (44.2 ± 9.5 years) finishing a MUM (330 km, elevation + 24000 m). Quantitative measurements of brain diffusion-weighted images (DWI) were performed at 3 time-points: Before the race, upon arrival and after 48 h. Multiple blood biomarkers were simultaneously investigated. Data analyses included brain apparent diffusion coefficient (ADC) and physiological data comparisons between three time-points. Results:The whole brain ADC significantly increased from baseline to arrival (p = 0.005) and then significantly decreased at recovery (p = 0.005) to lower values than at baseline (p = 0.005). While sodium, potassium, calcium, and chloride as well as hematocrit (HCT) changed over time, the serum osmolality remained constant. Significant correlations were found between whole brain ADC changes and osmolality (p = 0.01), cholesterol (p = 0.009), c-reactive protein (p = 0.04), sodium (p = 0.01), and chloride (p = 0.002) plasma level variations. Conclusions:These results suggest the relative increase of the inter-cellular volume upon arrival, and subsequently its reduction to lower values than at baseline, indicating that even after 48 h the brain has not fully recovered to its equilibrium state. Even though serum electrolytes may only indirectly indicate modifications at the brain level due

  15. Impact of ultra-viscous drops: air-film gliding and extreme wetting

    KAUST Repository

    Langley, K.

    2017-01-23

    A drop impacting on a solid surface must push away the intervening gas layer before making contact. This entails a large lubricating air pressure which can deform the bottom of the drop, thus entrapping a bubble under its centre. For a millimetric water drop, the viscous-dominated flow in the thin air layer counteracts the inertia of the drop liquid. For highly viscous drops the viscous stresses within the liquid also affect the interplay between the drop and the gas. Here the drop also forms a central dimple, but its outer edge is surrounded by an extended thin air film, without contacting the solid. This is in sharp contrast with impacts of lower-viscosity drops where a kink in the drop surface forms at the edge of the central disc and makes a circular contact with the solid. Larger drop viscosities make the central air dimple thinner. The thin outer air film subsequently ruptures at numerous random locations around the periphery, when it reaches below 150 nm thickness. This thickness we measure using high-speed two-colour interferometry. The wetted circular contacts expand rapidly, at orders of magnitude larger velocities than would be predicted by a capillary-viscous balance. The spreading velocity of the wetting spots is independent of the liquid viscosity. This may suggest enhanced slip of the contact line, assisted by rarefied-gas effects, or van der Waals forces in what we call extreme wetting. Myriads of micro-bubbles are captured between the local wetting spots.

  16. On the Dearth of Ultra-faint Extremely Metal-poor Galaxies

    Science.gov (United States)

    Sánchez Almeida, J.; Filho, M. E.; Dalla Vecchia, C.; Skillman, E. D.

    2017-02-01

    Local extremely metal-poor galaxies (XMPs) are of particular astrophysical interest since they allow us to look into physical processes characteristic of the early universe, from the assembly of galaxy disks to the formation of stars in conditions of low metallicity. Given the luminosity–metallicity relationship, all galaxies fainter than Mr ≃ ‑13 are expected to be XMPs. Therefore, XMPs should be common in galaxy surveys. However, they are not common, because several observational biases hamper their detection. This work compares the number of faint XMPs in the SDSS-DR7 spectroscopic survey with the expected number, given the known biases and the observed galaxy luminosity function (LF). The faint end of the LF is poorly constrained observationally, but it determines the expected number of XMPs. Surprisingly, the number of observed faint XMPs (∼10) is overpredicted by our calculation, unless the upturn in the faint end of the LF is not present in the model. The lack of an upturn can be naturally understood if most XMPs are central galaxies in their low-mass dark matter halos, which are highly depleted in baryons due to interaction with the cosmic ultraviolet background and to other physical processes. Our result also suggests that the upturn toward low luminosity of the observed galaxy LF is due to satellite galaxies.

  17. On the dearth of ultra-faint extremely metal poor galaxies

    CERN Document Server

    Almeida, J Sanchez; Vecchia, C Dalla; Skillman, E D

    2016-01-01

    Local extremely metal-poor (XMP) galaxies are of particular astrophysical interest since they allow us to look into physical processes characteristic of the early Universe, from the assembly of galaxy disks to the formation of stars in conditions of low metallicity. Given the luminosity-metallicity relationship, all galaxies fainter than Mr < -13 are expected to be XMPs. Therefore, XMPs should be common in galaxy surveys. However, they are not, because several observational biases hamper their detection. This work compares the number of faint XMPs in the SDSS-DR7 spectroscopic survey with the expected number, given the known biases and the observed galaxy luminosity function. The faint end of the luminosity function is poorly constrained observationally, but it determines the expected number of XMPs. Surprisingly, the number of observed faint XMPs (around 10) is over-predicted by our calculation, unless the upturn in the faint end of the luminosity function is not present in the model. The lack of an uptur...

  18. 21 CFR 73.3107 - Carbazole violet.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Carbazole violet. 73.3107 Section 73.3107 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL LISTING OF COLOR... additive is carbazole violet (Pigment Violet 23) (CAS Reg. No. 6358-30-1, Colour Index No. 51319). (b)...

  19. Discharge status evaluation on external insulation of insulator based on results of ultra-violet radiation measurement and fuzzy reasoning%采用模糊推理对绝缘子放电紫外检测结果进行外绝缘放电状况评估

    Institute of Scientific and Technical Information of China (English)

    汪金刚; 张作鹏; 龙震泽; 任昌智; 邓旭东; 何为; 杨帆

    2011-01-01

    In this paper, a method based on the fuzzy theory and ultra-violet (UV) radiation measurement to ac cess the discharge status of external insulation of the insulator is presented. In this method, the amount of UV pul ses generated by corona discharge of insulator is measured firstly, while collecting temperature of environment and humidity information, and then the relationship between the inputs is confirmed by analyzing online monitoring da ta, a series of fuzzy sets for fuzzy reasoning is set up, and the membership function is derived, fuzzy inference rules are established. Then the fuzzy reasoning is carried out to estimate the discharge status of external insulation. Final ly, the validity of this method is verified by simulating and analyzing the data detected from the tests of connecting to grid in Simulink.%根据紫外测量法[5]获得的绝缘子放电强度,提出了采用模糊推理对绝缘子外绝缘放电状况进行评估的方法.该方法首先测量绝缘子电晕放电产生的紫外光脉冲数量,同时采集环境温度、湿度信息,根据在线监测的数据分析确定各输入量之同的关系,建立了一系列可用于模糊推理的模糊子集,并对其隶属度函数进行了推导,建立详尽的模糊推理规则,进行模糊推理,判断其外绝缘放电状况.最后,针对现场挂网试验数据,采用simulink进行仿真分析,验证了该方法的有效性.

  20. Biodegradation of Crystal Violet by Agrobacterium radiobacter

    DEFF Research Database (Denmark)

    Parshetti, G.K.; Parshetti, S.G.; Telke, A.A.

    2011-01-01

    and phenol. We proposed the hypothetical metabolic pathway of Crystal Violet biodegradation by A. radiobacter. Phytotoxicity and microbial toxicity study showed that Crystal Violet biodegradation metabolites were less toxic to bacteria (A. radiobacter, P. aurugenosa and A. vinelandii) contributing to soil...

  1. Observation of extremely strong shock waves in solids launched by petawatt laser heating

    Science.gov (United States)

    Lancaster, K. L.; Robinson, A. P. L.; Pasley, J.; Hakel, P.; Ma, T.; Highbarger, K.; Beg, F. N.; Chen, S. N.; Daskalova, R. L.; Freeman, R. R.; Green, J. S.; Habara, H.; Jaanimagi, P.; Key, M. H.; King, J.; Kodama, R.; Krushelnick, K.; Nakamura, H.; Nakatsutsumi, M.; MacKinnon, A. J.; MacPhee, A. G.; Stephens, R. B.; Van Woerkom, L.; Norreys, P. A.

    2017-08-01

    Understanding hydrodynamic phenomena driven by fast electron heating is important for a range of applications including fast electron collimation schemes for fast ignition and the production and study of hot, dense matter. In this work, detailed numerical simulations modelling the heating, hydrodynamic evolution, and extreme ultra-violet (XUV) emission in combination with experimental XUV images indicate shock waves of exceptional strength (200 Mbar) launched due to rapid heating of materials via a petawatt laser. We discuss in detail the production of synthetic XUV images and how they assist us in interpreting experimental XUV images captured at 256 eV using a multi-layer spherical mirror.

  2. Ultra-thin metamaterial absorber with extremely bandwidth for solar cell and sensing applications in visible region

    Science.gov (United States)

    Tang, Jingyao; Xiao, Zhongyin; Xu, Kaikai

    2016-10-01

    In this paper, we proposed a broadband and ultra-thin metamaterial absorber in the visible region. The absorber is composed of three layers, and the most remarkable difference is that the split ring resonators (SRR) made of metal stannum are encrusted in the indium antimonide (InSb) plane on the top layer. Numerical results reveal that a broadband absorption spectrum above 90% can be realized from 353.9 THz to 613.2 THz due to the coupling effect between the material of stannum and InSb. The metamaterial absorber is ultra-thin, having the total thickness of 56 nm, i.e. less than λ/10 with respect to the center frequency of the absorption band more than 90%. In addition, the impedance matching theory, surface current distributions, E-field and H-field are investigated to explain the physical mechanism of the absorption. The sensing applications are discussed and the simulated results show that the proposed absorber operates well with a good efficiency. Moreover, the visible absorber has potential applications in the aspects of solar energy harvest, integrated photodetectors and so on.

  3. Exposure time to sunlight for ultra violet light therapy

    Directory of Open Access Journals (Sweden)

    Srinivas C

    1991-01-01

    Full Text Available Exposure time to sunlight for photo or photochemotherapy is arbitrarily determined. This could lead to inadequate or over exposure. As a sequence to our initial pilot study on exposure time for PUVASOL, we have now developed a bar chart which could be used as a guide to achieve a more logical and uniform exposure time during different months. We plan to extend the study to different zones in India.

  4. Rocksalt MgS solar blind ultra-violet detectors

    Directory of Open Access Journals (Sweden)

    Ying-Hoi Lai

    2012-03-01

    Full Text Available Studies using in-situ Auger electron spectroscopy and reflection high energy electron diffraction, and ex-situ high resolution X-ray diffraction and electron backscatter diffraction reveal that a MgS thin film grown directly on a GaAs (100 substrate by molecular beam epitaxy adopts its most stable phase, the rocksalt structure, with a lattice constant of 5.20 Å. A Au/MgS/n+-GaAs (100 Schottky-barrier photodiode was fabricated and its room temperature photoresponse was measured to have a sharp fall-off edge at 235 nm with rejection of more than three orders at 400 nm and higher than five orders at 500 nm, promising for various solar-blind UV detection applications.

  5. Ultra-violet-resistant mutants of Bacillus thuringiensis

    Energy Technology Data Exchange (ETDEWEB)

    Jones, D.R.; Karunakaran, V. (Polytechnic of Central London (UK). Faculty of Engineering and Science, School of Biological and Health Sciences); Burges, H.D. (Institute of Horticultural Research, Littlehampton (UK)); Hacking, A.J. (Reading Univ. (UK). Dextra Labs.Ltd.)

    1991-06-01

    One of the main disadvantages of using Bacillus thuringiensis as an insecticide is that the spore and crystal preparations applied to foliage are readily washed away by rain and are inactivated by sunlight. Spores from some strains of B. thuringiensis have been shown to be highly sensitive to u.v. light. This study has demonstrated how mutants with increased resistance to u.v., isolated by successive rounds of u.v. irradiation, and additionally with increased specific pathogenicity can be isolated. These techniques should be applied to strains that are frequently used in the industrial production of B.thuringiensis toxin. (author).

  6. Discovering extremely compact and metal-poor, star-forming dwarf galaxies out to z ~ 0.9 in the VIMOS Ultra-Deep Survey

    CERN Document Server

    Amorín, Ricardo; Castellano, M; Grazian, A; Tasca, L A M; Fontana, A; Pentericci, L; Cassata, P; Garilli, B; Brun, V Le; Fèvre, O Le; Maccagni, D; Thomas, R; Vanzella, E; Zamorani, G; Zucca, E; Bardelli, S; Capak, P; Cassará, L; Cimatti, A; Cuby, J G; Cucciati, O; de la Torre, S; Durkalec, A; Giavalisco, M; Hathi, N P; Ilbert, O; Lemaux, B C; Moreau, C; Paltani, S; Ribeiro, B; Salvato, M; Schaerer, D; Scodeggio, M; Talia, M; Taniguchi, Y; Tresse, L; Vergani, D; Wang, P W; Charlot, S; Contini, T; Fotopoulou, S; López-Sanjuan, C; Mellier, Y; Scoville, N

    2014-01-01

    We report the discovery of 31 low-luminosity (-14.5 < M_{AB}(B) < -18.8), extreme emission line galaxies (EELGs) at 0.3 < z < 0.9 identified by their unusually high rest-frame equivalent widths (100 < EW[OIII] < 1700 A) as part of the VIMOS Ultra Deep Survey (VUDS). VIMOS optical spectra of unprecedented sensitivity ($I_{AB}$ ~ 25 mag) along with multiwavelength photometry and HST imaging are used to investigate spectrophotometric properties of this unique sample and explore, for the first time, the very low stellar mass end (M* < 10^8 M$_{\\odot}$) of the luminosity-metallicity (LZR) and mass-metallicity (MZR) relations at z < 1. Characterized by their extreme compactness (R50 < 1 kpc), low stellar mass and enhanced specific star formation rates (SFR/M* ~ 10^{-9} - 10^{-7} yr^{-1}), the VUDS EELGs are blue dwarf galaxies likely experiencing the first stages of a vigorous galaxy-wide starburst. Using T_e-sensitive direct and strong-line methods, we find that VUDS EELGs are low-metall...

  7. Biodegradation of Crystal Violet by Agrobacterium radiobacter

    Institute of Scientific and Technical Information of China (English)

    G.K.Parshetti; S.G.Parshetti; A.A.Telke; D.C.Kalyani; R.A.Doong; S.P.Govindwar

    2011-01-01

    Agrobacterium radiobacter MTCC 8161 completely decolorized the Crystal Violet with 8 hr (10 mg/L) at static anoxic conditions.The decreased decolorization capability by A.radiobacter was observed,when the Crystal Violet concentration was increased from 10 to 100 mg/L.Semi-synthetic medium containing 1% yeast extract and 0.1% NH4Cl has shown 100% decolorization of Crystal Violet within 5 hr.A complete degradation of Crystal Violet by A.radiobacter was observed up to 7 cycles of repeated addition (10 mg/L).When the effect of increasing inoculum concentration on decolorization of Crystal Violet (100 rag/L) was studied,maximum decolorization was observed with 15% inoculum concentration.A significant increase in the activities of laccase (184%) and aminopyrine N-demethylase (300%) in cells obtained after decolorization indicated the involvement of these enzymes in decolorization process.The intermediates formed during the degradation of Crystal Violet were analyzed by gas chromatography and mass spectroscopy (GC/MS).It was detected the presence of N,N,N′,N"-tetramethylpararosaniline,[N,N-dimethylaminophenyl][N-methylaminophenyl] benzophenone,N,N-dimethylaminobenzaldehyde,4-methyl amino phenol and phenol.We proposed the hypothetical metabolic pathway of Crystal Violet biodegradation by A.radiobacter.Phytotoxicity and microbial toxicity study showed that Crystal Violet biodegradation metabolites were less toxic to bacteria (A.radiobacter,P.aurugenosa and A.vinelandii) contributing to soil fertility and for four kinds of plants (Sorghum bicolor,Vigna radiata,Lens culinaris and Triticum aestivum) which are most sensitive,fast growing and commonly used in Indian agriculture.

  8. Discharge-produced plasma extreme ultraviolet (EUV) source and ultra high vacuum chamber for studying EUV-induced processes

    CERN Document Server

    Dolgov, A; Abrikosov, A; Snegirev, E; Krivtsun, V M; Lee, C J; Bijkerk, F

    2014-01-01

    An experimental setup that directly reproduces Extreme UV-lithography relevant conditions for detailed component exposure tests is described. The EUV setup includes a pulsed plasma radiation source, operating at 13.5 nm; a debris mitigation system; collection and filtering optics; and an UHV experimental chamber, equipped with optical and plasma diagnostics. The first results, identifying the physical parameters and evolution of EUV-induced plasmas are presented. Finally, the applicability and accuracy of the in situ diagnostics is briefly discussed.

  9. [Qualitative Determination of Organic Vapour Using Violet and Visible Spectrum].

    Science.gov (United States)

    Jiang, Bo; Hu, Wen-zhong; Liu, Chang-jian; Zheng, Wei; Qi, Xiao-hui; Jiang, Ai-li; Wang, Yan-ying

    2015-12-01

    Vapours of organic matters were determined qualitatively employed with ultraviolet-visible absorption spectroscopy. Vapours of organic matters were detected using ultraviolet-visible spectrophotometer employing polyethylene film as medium, the ultraviolet and visible absorption spectra of vegetable oil vapours of soybean oil, sunflower seed oil, peanut oil, rapeseed oil, sesame oil, cotton seed oil, tung tree seed oil, and organic compound vapours of acetone, ethyl acetate, 95% ethanol, glacial acetic acid were obtained. Experimental results showed that spectra of the vegetable oil vapour and the organic compound vapour could be obtained commendably, since ultra violet and visible spectrum of polyethylene film could be deducted by spectrograph zero setting. Different kinds of vegetable oils could been distinguished commendably in the spectra since the λ(max), λ(min), number of absorption peak, position, inflection point in the ultra violet and visible spectra obtained from the vapours of the vegetable oils were all inconsistent, and the vapours of organic compounds were also determined perfectly. The method had a good reproducibility, the ultraviolet and visible absorption spectra of the vapours of sunflower seed oil in 10 times determination were absolutely the same. The experimental result indicated that polyethylene film as a kind of medium could be used for qualitative analysis of ultraviolet and visible absorption spectroscopy. The method for determination of the vapours of the vegetable oils and organic compounds had the peculiarities of fast speed analysis, well reproducibility, accuracy and reliability and low cost, and so on. Ultraviolet and visible absorption spectrum of organic vapour could provide feature information of material vapour and structural information of organic compound, and provide a novel test method for identifying vapour of compound and organic matter.

  10. High-Redshift Extremely Red Objects in the HST Ultra Deep Field Revealed by the GOODS IRAC Observations

    CERN Document Server

    Yan, H; Eisenhardt, P R M; Ferguson, H C; Grogin, N A; Paolillo, M; Chary, R R; Casertano, S; Stern, D; Reach, W T; Moustakas, L A; Fall, S M; Yan, Haojing; Dickinson, Mark; Eisenhardt, Peter R. M.; Ferguson, Henry C.; Grogin, Norman A.; Paolillo, Maurizio; Chary, Ranga-Ram; Casertano, Stefano; Stern, Daniel; Reach, William T.; Moustakas, Leonidas A.

    2004-01-01

    Using early data from the Infrared Array Camera (IRAC) on the Spitzer Space Telescope, taken for the Great Observatories Origins Deep Survey (GOODS), we identify and study objects that are well-detected at 3.6um, but are very faint (and in some cases, invisible) in the Hubble Ultra Deep Field (HUDF) ACS and NICMOS images and in very deep VLT Ks-band imaging. We select a sample of 17 objects with f_nu(3.6um)/f_nu(z_{850})>20. The analysis of their spectral energy-distributions (SEDs) from 0.4 to 8.0um shows that the majority of these objects cannot be satisfactorily explained without a well-evolved stellar population. We find that most of them can be well fitted by a simple two-component model, where the primary component represents a massive, old population that dominates the strong IR emission, while the secondary component represents a low amplitude, on-going star-formation process that accounts for the weak optical fluxes. Their estimated photometric redshifts (z_p) range from 1.6 to 2.9, with the median a...

  11. Au-C allotrope nano-composite films at extreme conditions generated by intense ultra-short laser

    Science.gov (United States)

    Khan, Saif A.; Saravanan, K.; Tayyab, M.; Bagchi, S.; Avasthi, D. K.

    2016-07-01

    Structural evolution of gold-carbon allotrope nano-composite films under relativistically intense, ultra-short laser pulse irradiation is studied in this work. Au-C nano-composite films, having 4 and 10 at.% of Au, were deposited by co-sputtering technique on silicon substrates. Au-C60 NC films with 2.5 at.% Au were deposited on 12 μm thick Al foil using co-evaporation technique. These samples were radiated with single pulse from 45 fs, 10 TW Ti:Sapphire Laser at RRCAT at an intensity of 3 × 1018 W cm-2. The morphological and compositional changes were investigated using scanning electron microscopy (SEM) and Rutherford back-scattering spectrometry (RBS) techniques. Laser pulse created three morphologically distinct zones around the point of impact on samples with silicon substrates. The gold content in 600 μm circular region around a point of impact is found to reduce by a factor of five. Annular rings of ∼70 nm in diameter were observed in case of Au-C NC film after irradiation. Laser pulse created a hole of about 400 μm in the sample with Al foil as substrate and wavy structures of 6 μm wavelength are found to be created around this hole. The study shows radial variation in nano-structure formation with varying local intensity of laser pulse.

  12. Au–C allotrope nano-composite films at extreme conditions generated by intense ultra-short laser

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Saif A., E-mail: khansaifahmad@gmail.com [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Saravanan, K. [Department of Physics, Tamkang University, Tamsui 251, Taiwan (China); Tayyab, M.; Bagchi, S. [Laser Plasma Division, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India); Avasthi, D.K. [Inter-University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi 110067 (India); Amity University, Noida 201313, Uttar Pradesh (India)

    2016-07-15

    Structural evolution of gold–carbon allotrope nano-composite films under relativistically intense, ultra-short laser pulse irradiation is studied in this work. Au–C nano-composite films, having 4 and 10 at.% of Au, were deposited by co-sputtering technique on silicon substrates. Au–C{sub 60} NC films with 2.5 at.% Au were deposited on 12 μm thick Al foil using co-evaporation technique. These samples were radiated with single pulse from 45 fs, 10 TW Ti:Sapphire Laser at RRCAT at an intensity of 3 × 10{sup 18} W cm{sup −2}. The morphological and compositional changes were investigated using scanning electron microscopy (SEM) and Rutherford back-scattering spectrometry (RBS) techniques. Laser pulse created three morphologically distinct zones around the point of impact on samples with silicon substrates. The gold content in 600 μm circular region around a point of impact is found to reduce by a factor of five. Annular rings of ∼70 nm in diameter were observed in case of Au–C NC film after irradiation. Laser pulse created a hole of about 400 μm in the sample with Al foil as substrate and wavy structures of 6 μm wavelength are found to be created around this hole. The study shows radial variation in nano-structure formation with varying local intensity of laser pulse.

  13. Metal-Poor Stars Observed with the Magellan Telescope. III. New Extremely and Ultra Metal-Poor Stars from SDSS/SEGUE and Insights on the Formation of Ultra Metal-Poor Stars

    CERN Document Server

    Placco, Vinicius M; Lee, Young Sun; Jacobson, Heather R; Beers, Timothy C; Pena, Jose M; Chan, Conrad; Heger, Alexander

    2015-01-01

    We report the discovery of one extremely metal-poor (EMP; [Fe/H]<-3) and one ultra metal-poor (UMP; [Fe/H]<-4) star selected from the SDSS/SEGUE survey. These stars were identified as EMP candidates based on their medium-resolution (R~2,000) spectra, and were followed-up with high-resolution (R~35,000) spectroscopy with the Magellan-Clay Telescope. Their derived chemical abundances exhibit good agreement with those of stars with similar metallicities. We also provide new insights on the formation of the UMP stars, based on comparison with a new set of theoretical models of supernovae nucleosynthesis. The models were matched with 20 UMP stars found in the literature, together with one of the program stars (SDSS J1204+1201), with [Fe/H]=-4.34. From fitting their abundances, we find that the supernovae progenitors, for stars where carbon and nitrogen are measured, had masses ranging from 20.5 M_sun to 28 M_sun and explosion energies from 0.3 to 0.9x10^51 erg. These results are highly sensitive to the carbo...

  14. Amplification of coherent synchrotron high harmonic emission from ultra-thin foils in relativistic light fields

    Science.gov (United States)

    Braenzel, J.; Andreev, A. A.; Platonov, K. Y.; Ehrentraut, L.; Schnürer, M.

    2017-08-01

    We report on a remarkable enhancement of high harmonic (HH) radiation emitted from the interaction of an ultra-intense laser pulse with ultra-thin foils by a manipulation of foil pre-plasma conditions. With a strong counter-propagating pre-pulse, we introduce a concerted expansion of the ultrathin foil target, and this significantly raises the efficiency of the HH generation process. Our experimental results show how the emission efficiency can be easily controlled by the intensity and delay time of the pre-pulse. The results give an important insight into the high harmonic generation process from solid dense plasmas when spatially limited. 1D particles in cell simulations confirm our experimental findings and show a significant dependency of the HH emission efficiency on the plasma density. The simplicity of the ultra-thin foil target and interaction geometry hold promise for specifically compact realization of imaging experiments with ultra-short and bright extreme ultra violet-pulses.

  15. Ultra-high performance fibre-reinforced concrete under impact: experimental analysis of the mechanical response in extreme conditions and modelling using the Pontiroli, Rouquand and Mazars model

    Science.gov (United States)

    Erzar, Benjamin; Pontiroli, Christophe; Buzaud, Eric

    2017-01-01

    To evaluate the vulnerability of ultra-high performance fibre-reinforced concrete (UHPFRC) infrastructure to rigid projectile penetration, over the last few years CEA-Gramat has led an experimental and numerical research programme in collaboration with French universities. During the penetration process, concrete is subjected to extreme conditions of pressure and strain rate. Plasticity mechanisms as well as dynamic tensile and/or shear damage are activated during the tunnelling phase and the cratering of the concrete target. Each mechanism has been investigated independently at the laboratory scale and the role of steel fibres especially has been analysed to understand their influence on the macroscopic behaviour. To extend the experimental results to the structural scale, penetration tests on UHPFRC slabs have been conducted by CEA-Gramat. The analysis of this dataset combined with material characterization experiments allows the role of steel fibres to be identified in the different plasticity and damage mechanisms occurring during penetration. In parallel, some improvements have been introduced into the concrete model developed by Pontiroli, Rouquand and Mazars (PRM model), especially to take into account the contribution made by the fibres in the tensile fracture process. After a primary phase of validation, the capabilities of the PRM model are illustrated by performing numerical simulations of projectile penetration into UHPFRC concrete structures. This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

  16. Ultra-high performance fibre-reinforced concrete under impact: experimental analysis of the mechanical response in extreme conditions and modelling using the Pontiroli, Rouquand and Mazars model.

    Science.gov (United States)

    Erzar, Benjamin; Pontiroli, Christophe; Buzaud, Eric

    2017-01-28

    To evaluate the vulnerability of ultra-high performance fibre-reinforced concrete (UHPFRC) infrastructure to rigid projectile penetration, over the last few years CEA-Gramat has led an experimental and numerical research programme in collaboration with French universities. During the penetration process, concrete is subjected to extreme conditions of pressure and strain rate. Plasticity mechanisms as well as dynamic tensile and/or shear damage are activated during the tunnelling phase and the cratering of the concrete target. Each mechanism has been investigated independently at the laboratory scale and the role of steel fibres especially has been analysed to understand their influence on the macroscopic behaviour. To extend the experimental results to the structural scale, penetration tests on UHPFRC slabs have been conducted by CEA-Gramat. The analysis of this dataset combined with material characterization experiments allows the role of steel fibres to be identified in the different plasticity and damage mechanisms occurring during penetration. In parallel, some improvements have been introduced into the concrete model developed by Pontiroli, Rouquand and Mazars (PRM model), especially to take into account the contribution made by the fibres in the tensile fracture process. After a primary phase of validation, the capabilities of the PRM model are illustrated by performing numerical simulations of projectile penetration into UHPFRC concrete structures.This article is part of the themed issue 'Experimental testing and modelling of brittle materials at high strain rates'.

  17. Violet stimulated luminescence: geo- or thermochronometer?

    DEFF Research Database (Denmark)

    Ankjærgaard, Christina; Guralnik, Benny; Porat, N.

    2015-01-01

    The method of quartz optically stimulated luminescence (OSL) dating is widely used, but generally limited to the past ~0.1 million years (Ma) due to early saturation of the desired signal. Violet stimulated luminescence (VSL) of quartz has previously been shown as a promising alternative...

  18. 21 CFR 589.1000 - Gentian violet.

    Science.gov (United States)

    2010-04-01

    ... violation of the Federal Food, Drug, and Cosmetic Act (the act), in the absence of a regulation providing... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Gentian violet. 589.1000 Section 589.1000 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL...

  19. Violet stimulated luminescence: geo- or thermochronometer?

    DEFF Research Database (Denmark)

    Ankjærgaard, Christina; Guralnik, Benny; Porat, N.;

    2015-01-01

    The method of quartz optically stimulated luminescence (OSL) dating is widely used, but generally limited to the past ~0.1 million years (Ma) due to early saturation of the desired signal. Violet stimulated luminescence (VSL) of quartz has previously been shown as a promising alternative...

  20. Adsorption kinetics of methyl violet onto perlite.

    Science.gov (United States)

    Doğan, Mehmet; Alkan, Mahir

    2003-01-01

    This study examines adsorption kinetics and activation parameters of methyl violet on perlite. The effect of process parameters like contact time, concentration of dye, temperature and pH on the extent of methyl violet adsorption from solution has been investigated. Results of the kinetic studies show that the adsorption reaction is first order with respect to dye solution concentration with activation energy of 13.2 kJ mol(-1). This low activation energy value indicates that the adsorption reaction is diffusion controlled. The activation parameters using Arrhenius and Eyring equations have been calculated. Adsorption increases with increase of variables such as contact time, initial dye concentration, temperature and pH.

  1. Micropropagation of African violet (Saintpaulia ionantha Wendl.).

    Science.gov (United States)

    Shukla, Mukund; Sullivan, J Alan; Jain, Shri Mohan; Murch, Susan J; Saxena, Praveen K

    2013-01-01

    Micropropagation is an important tool for rapid multiplication and the creation of genetic variability in African violets (Saintpaulia ionantha Wendl.). Successful in vitro propagation depends on the specific requirements and precise manipulation of various factors such as the type of explants used, physiological state of the mother plant, plant growth regulators in the culture medium, and growth conditions. Development of cost-effective protocols with a high rate of multiplication is a crucial requirement for commercial application of micropropagation. The current chapter describes an optimized protocol for micropropagation of African violets using leaf explants obtained from in vitro grown plants. In this process, plant regeneration occurs via both somatic embryogenesis and shoot organogenesis simultaneously in the explants induced with the growth regulator thidiazuron (TDZ; N-phenyl-N'-1,2,3-thidiazol-5-ylurea). The protocol is simple, rapid, and efficient for large-scale propagation of African violet and the dual routes of regeneration allow for multiple applications of the technology from simple clonal propagation to induction or selection of variants to the production of synthetic seeds.

  2. Evolutionary replacement of UV vision by violet vision in fish

    Science.gov (United States)

    Tada, Takashi; Altun, Ahmet; Yokoyama, Shozo

    2009-01-01

    The vertebrate ancestor possessed ultraviolet (UV) vision and many species have retained it during evolution. Many other species switched to violet vision and, then again, some avian species switched back to UV vision. These UV and violet vision are mediated by short wavelength-sensitive (SWS1) pigments that absorb light maximally (λmax) at approximately 360 and 390–440 nm, respectively. It is not well understood why and how these functional changes have occurred. Here, we cloned the pigment of scabbardfish (Lepidopus fitchi) with a λmax of 423 nm, an example of violet-sensitive SWS1 pigment in fish. Mutagenesis experiments and quantum mechanical/molecular mechanical (QM/MM) computations show that the violet-sensitivity was achieved by the deletion of Phe-86 that converted the unprotonated Schiff base-linked 11-cis-retinal to a protonated form. The finding of a violet-sensitive SWS1 pigment in scabbardfish suggests that many other fish also have orthologous violet pigments. The isolation and comparison of such violet and UV pigments in fish living in different ecological habitats will open an unprecedented opportunity to elucidate not only the molecular basis of phenotypic adaptations, but also the genetics of UV and violet vision. PMID:19805066

  3. Removal of Crystal Violet dye from aqueous solution using water hyacinth: Equilibrium, kinetics and thermodynamics study

    Directory of Open Access Journals (Sweden)

    M. Rajeswari Kulkarni

    2017-03-01

    Full Text Available Effluent water from dyeing industries has now for long been a taxing issue. Of the various dyes which are extremely toxic, Crystal Violet which is used in the dyeing industry is known for its mutagenic and mitotic poisoning nature. Water hyacinth (Eichhornia crassipes is a perennial aquatic plant notorious for its rapid invasive growth on the surface of water bodies causing ill-effects on the biodiversity. The potential of powdered roots of water hyacinth was studied for decolorization of Crystal Violet dye. Influence of parameters such as initial pH (2.0–10.0, initial dye concentration (100–500 ppm, biosorbent dosage (0.5–5 g/l, contact time (10–240 min and temperature (300–323 K were examined. Maximum removal of dye was observed at pH 7.8. The obtained data were fit into different kinetic models and the biosorption was found to follow pseudo second order kinetic model. The Langmuir monolayer biosorption capacity of water hyacinth was estimated as 322.58 mg/g. The study has demonstrated water hyacinth as a potential low cost biosorbent for effective removal of Crystal Violet dye from aqueous solution.

  4. The PL "violet shift" of cerium dioxide on silicon

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    CeO2 thin film was fabricated by dual ion beam epitaxial technique. The phenomenon of PL violet shift at room temperature was observed, and the distance of shift was about 65 nm. After the analysis of crystal structure and valence in the compound were carried out by XRD and XPS technique, it was concluded that the PL shift was related with valence of cerium ion in the oxides. When the valence of cerium ion varied from tetravalence to trivalence, the PL peak position would move from blue region to violet region and the phenomenon of "violet shift" was observed.

  5. Biodegradation of methyl violet by Pseudomonas mendocina MCM B-402.

    Science.gov (United States)

    Sarnaik, S; Kanekar, P

    1999-08-01

    Pseudomonas mendocina MCM B-402 was found to utilize a triphenylmethane dye, methyl violet as the sole source of carbon when incorporated in synthetic medium. Almost complete decolorization of methyl violet by P. mendocina was observed within 48 h of incubation at ambient temperature (28 +/- 2 degrees C) under aerated culture conditions, when the bacteria were inoculated into Davis Mingioli's synthetic medium at a concentration of 100 mg/l medium. Methyl violet was mineralized to CO2 through three unknown intermediate metabolites and phenol. The decolorization of the dye involved demethylation.

  6. Removal of methyl violet from aqueous solution by perlite.

    Science.gov (United States)

    Doğan, Mehmet; Alkan, Mahir

    2003-11-01

    The use of perlite for the removal of methyl violet from aqueous solutions at different concentration, pH, and temperature has been investigated. Adsorption equilibrium is reached within 1 h. The capacity of perlite samples for the adsorption of methyl violet was found to increase with increasing pH and temperature and decrease with expansion and increasing acid-activation. The adsorption isotherms are described by means of the Langmuir and Freundlich isotherms. The adsorption isotherm was measured experimentally at different conditions and the experimental data were correlated reasonably well by the adsorption isotherm of Langmuir. The order of heat of adsorption corresponds to a physical reaction. It is concluded that the methyl violet is physically adsorbed onto the perlite. The removal efficiency (P) and dimensionless separation factor (R) have shown that perlite can be used for removal of methyl violet from aqueous solutions, but unexpanded perlite is more effective.

  7. Violet Laser Diode Enables Lighting Communication.

    Science.gov (United States)

    Chi, Yu-Chieh; Huang, Yu-Fang; Wu, Tsai-Chen; Tsai, Cheng-Ting; Chen, Li-Yin; Kuo, Hao-Chung; Lin, Gong-Ru

    2017-09-05

    Violet laser diode (VLD) based white-light source with high color rendering index (CRI) for lighting communication is implemented by covering with Y3Al5O12:Ce(3+) (YAG:Ce) or Lu3Al5O12:Ce(3+)/CaAlSiN3:Eu(2+) (LuAG:Ce/CASN:Eu) phosphorous diffuser plates. After passing the beam of VLD biased at 70 mA (~2I th ) through the YAG:Ce phosphorous diffuser, a daylight with a correlated color temperature (CCT) of 5068 K and a CRI of 65 is acquired to provide a forward error correction (FEC) certified data rate of 4.4 Gbit/s. By using the VLD biased at 122 mA (~3.5I th ) to excite the LuAG:Ce/CASN:Eu phosphorous diffuser with 0.85-mm thickness, a warm white-light source with a CCT of 2700 K and a CRI of 87.9 is obtained at a cost of decreasing transmission capacity to 2.4 Gbit/s. Thinning the phosphor thickness to 0.75 mm effectively reduces the required bias current by 32 mA to achieve the same CCT for the delivered white light, which offers an enlarged CRI of 89.1 and an increased data rate of 4.4 Gbit/s. Further enlarging the bias current to 105 mA remains the white-light transmission capacity at 4.4 Gbit/s but reveals an increased CCT of 3023 K and an upgraded CRI of 91.5.

  8. EUV SpectroPhotometer (ESP) in Extreme Ultraviolet Variability Experiment (EVE): Algorithms and Calibrations

    CERN Document Server

    Didkovsky, Leonid; Wieman, Seth; Woods, Tom; Jones, Andrew

    2009-01-01

    The Extreme ultraviolet SpectroPhotometer (ESP) is one of five channels of the Extreme ultraviolet Variability Experiment (EVE) onboard the NASA Solar Dynamics Observatory (SDO). The ESP channel design is based on a highly stable diffraction transmission grating and is an advanced version of the Solar Extreme ultraviolet Monitor (SEM), which has been successfully observing solar irradiance onboard the Solar and Heliospheric Observatory (SOHO) since December 1995. ESP is designed to measure solar Extreme UltraViolet (EUV) irradiance in four first order bands of the diffraction grating centered around 19 nm, 25 nm, 30 nm, and 36 nm, and in a soft X-ray band from 0.1 to 7.0 nm in the zeroth order of the grating. Each band's detector system converts the photo-current into a count rate (frequency). The count rates are integrated over 0.25 sec increments and transmitted to the EVE Science and Operations Center for data processing. An algorithm for converting the measured count rates into solar irradiance and the ES...

  9. On the design of experiments for the study of extreme field limits in the ultra-relativistic interaction of electromagnetic waves with plasmas

    Science.gov (United States)

    Bulanov, Sergei V.; Esirkepov, Timur Z.; Hayashi, Yukio; Kando, Masaki; Kiriyama, Hiromitsu; Koga, James K.; Kondo, Kiminori; Kotaki, Hideyuki; Pirozhkov, Alexander S.; Bulanov, Stepan S.; Zhidkov, Alexei G.; Chen, Pisin; Neely, David; Kato, Yoshiaki; Narozhny, Nikolay B.; Korn, Georg

    2011-06-01

    The critical electric field of quantum electrodynamics, called also the Schwinger field, is so strong that it produces electron-positron pairs from vacuum, converting the energy of light into matter. Since the dawn of quantum electrodynamics, there has been a dream on how to reach it on Earth. With the rise of laser technology this field has become feasible through the construction of extremely high power lasers or/and with the sophisticated use of nonlinear processes in relativistic plasmas. This is one of the most attractive motivations for extremely high power laser development, i.e. producing matter from vacuum by pure light in fundamental process of quantum electrodynamics in the nonperturbative regime. Recently it has been realized that a laser with intensity well below the Schwinger limit can create an avalanche of electron-positron pairs similar to a discharge before attaining the Schwinger field. It has also been realized that the Schwinger limit can be reached using an appropriate configuration of laser beams. In experiments on the collision of laser light and high intensity electromagnetic pulses generated by relativistic flying mirrors, with electron bunches produced by a conventional accelerator and with laser wake field accelerated electrons the studying of extreme field limits in the nonlinear interaction of electromagnetic waves is proposed. The regimes of dominant radiation reaction, which completely changes the electromagnetic wave-matter interaction, will be revealed. This will result in a new powerful source of high brightness gamma-rays. A possibility of the demonstration of the electronpositron pair creation in vacuum via multi-photon processes can be realized. This will allow modeling under terrestrial laboratory conditions neutron star magnetospheres, cosmological gamma ray bursts and the Leptonic Era of the Universe.

  10. Ablation of dentin by irradiation of violet diode laser

    Science.gov (United States)

    Hatayama, H.; Kato, J.; Akashi, G.; Hirai, Y.; Inoue, A.

    2006-02-01

    Several lasers have been used for clinical treatment in dentistry. Among them, diode lasers are attractive because of their compactness compared with other laser sources. Near-infrared diode lasers have been practically used for cutting soft tissues. Because they penetrate deep to soft tissues, they cause sufficiently thick coagulation layer. However, they aren't suitable for removal of carious dentin because absorption by components in dentin is low. Recently, a violet diode laser with a wavelength of 405nm has been developed. It will be effective for cavity preparation because dentin contains about 20% of collagen whose absorption coefficient at a violet wavelength is larger than that at a near-infrared wavelength. In this paper, we examined cutting performance of the violet diode laser for dentin. To our knowledge, there have been no previous reports on application of a violet laser to dentin ablation. Bovine teeth were irradiated by continuous wave violet diode laser with output powers in a range from 0.4W to 2.4W. The beam diameter on the sample was about 270μm and an irradiation time was one second. We obtained the crater ablated at more than an output power of 0.8W. The depth of crater ranged from 20μm at 0.8W to 90μm at 2.4W. Furthermore, the beam spot with an output power of 1.7W was scanned at a speed of 1mm/second corresponding to movement of a dentist's hand in clinical treatment. Grooves with the depth of more than 50μm were also obtained. From these findings, the violet diode laser has good potential for cavity preparation. Therefore, the violet diode laser may become an effective tool for cavity preparation.

  11. Violet-red discolouration of canned Palmyra palm during processing.

    Science.gov (United States)

    Chamchong, Montip; Tatidin, Yuporn; Misayan, Apinya

    2016-01-01

    The objectives of the research were to investigate the causes of the violet-red discolouration during processing of canned Palmyra palm and to identify preventive methods without the use of chemical additives. Palmyra palm flesh with (13-21 %) /without some peel left on was tested for the source of violet-red discolouration during blanching. It was found that blanching in distilled water had no effect on discolouration when blanching conditions were at 75, 85, and 95 °C for 7 min but the violet-red discolouration occurred only when tap water was used for blanching at 95 °C for 7 min. Moreover, the addition of bicarbonate (NaHCO3) in distilled water to imitate higher alkalinity of tap water during blanching could contribute to the violet-red discolouration. Thus the observed cut off alkalinity of the blanching water wherein not to expect any discolouration was found to be about 100 ppm. After sterilization, there was no violet-red discolouration from Palmyra palm flesh without any peel left on even though it had a preceding treatment of blanching in highly alkaline tap water.

  12. Facile preparation of stable palygorskite/methyl violet@SiO2 "Maya Violet" pigment.

    Science.gov (United States)

    Zhang, Yujie; Zhang, Junping; Wang, Aiqin

    2015-11-01

    Maya Blue pigment has attracted considerable attention owing to their extraordinary stability. The growing interest in this field has largely expanded the study of Maya Blue-like pigments. Inspired by Maya Blue, a stable palygorskite/methyl violet@SiO2 (PAL/MV@SiO2) "Maya Violet" pigment was fabricated via adsorption of MV by PAL, and then deposition of a layer of SiO2 on the surface by polycondensation of tetraethoxysilane (TEOS) in the presence of cetyltrimethylammonium bromide (CTAB). The weight ratio of MV to PAL is as high as 10%. The pigments were characterized by scanning electron microscopy and a variety of analytical techniques, e.g., Fourier Transform infrared spectroscopy and zeta potential. The results indicate that MV molecules are fixed onto the exterior surface, the grooves and at the entrances of the channels of PAL. The PAL/MV@SiO2 pigment shows excellent stability against chemical attacks, e.g., 0.1 M HCl, 0.1 M NaOH and various organic solvents. Different from Maya Blue, grinding and heating treatment are virtually ineffective in improving stability of the PAL/MV pigment. CTAB and the SiO2 layer formed on the surface of PAL/MV contribute greatly to the improved stability of the pigment due to shielding effect. The optimal CTAB/TEOS/ammonia/H2O molar ratio for the surface modification of PAL/MV is 0.24/1/2.89/495. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Spectral characteristics and nonlinear studies of crystal violet dye

    Science.gov (United States)

    Sukumaran, V. Sindhu; Ramalingam, A.

    2006-03-01

    Solid-state dye-doped polymer is an attractive alternative to the conventional liquid dye solution. In this paper, the spectral characteristics and the nonlinear optical properties of the dye crystal violet are studied. The spectral characteristics of crystal violet dye doped poly(methylmethacrylate) modified with additive n-butyl acetate (nBA) are studied by recording its absorption and fluorescence spectra and the results are compared with the corresponding liquid mixture. The nonlinear refractive index of the dye in nBA and dye doped polymer film were measured using z-scan technique, by exciting with He-Ne laser. The results obtained are intercompared. Both the samples of dye crystal violet show a negative nonlinear refractive index. The origin of optical nonlinearity in the dye may be attributed due to laser-heating induced nonlinear effect.

  14. Laser-Induced Fluorescence and Performance Analysis of the Ultra-Compact Combustor

    Science.gov (United States)

    2008-06-01

    fuel consumption TVC Trapped Vortex Combustion UCC Ultra Compact Combustor UHC Unburned hydrocarbons UV Ultra-violet VI Virtual Instrument 2-D...unburned hydrocarbons ( UHC ), oxides of nitrogen (NOx), carbon monoxide (CO), and soot particles (Turns, 2006:3). In conventional combustors, a high...power (fuel-rich) condition tends to produce more NOx and soot, while low power (fuel-lean) produces more UHC and CO (Quaale, 2003:27). While the UCC

  15. 75 FR 62765 - Carbazole Violet Pigment 23 From India: Final Results of Antidumping Duty Changed-Circumstances...

    Science.gov (United States)

    2010-10-13

    ... International Trade Administration Carbazole Violet Pigment 23 From India: Final Results of Antidumping Duty.... See Carbazole Violet Pigment 23 From India: Preliminary Results of Antidumping Duty Changed... most recently completed review. See Carbazole Violet Pigment 23 From India: Final Results...

  16. Moving in extreme environments

    DEFF Research Database (Denmark)

    Lucas, Samuel J E; Helge, Jørn W; Schütz, Uwe H W;

    2016-01-01

    This review addresses human capacity for movement in the context of extreme loading and with it the combined effects of metabolic, biomechanical and gravitational stress on the human body. This topic encompasses extreme duration, as occurs in ultra-endurance competitions (e.g. adventure racing...... and transcontinental races) and expeditions (e.g. polar crossings), to the more gravitationally limited load carriage (e.g. in the military context). Juxtaposed to these circumstances is the extreme metabolic and mechanical unloading associated with space travel, prolonged bedrest and sedentary lifestyle, which may...

  17. Quantifying hydrogen peroxide in iron-containing solutions using leuco crystal violet

    Directory of Open Access Journals (Sweden)

    Schoonen Martin A

    2005-06-01

    Full Text Available Hydrogen peroxide is present in many natural waters and wastewaters. In the presence of Fe(II, this species decomposes to form hydroxyl radicals, that are extremely reactive. Hence, in the presence of Fe(II, hydrogen peroxide is difficult to detect because of its short lifetime. Here, we show an expanded use of a hydrogen peroxide quantification technique using leuco crystal violet (LCV for solutions of varying pH and iron concentration. In the presence of the biocatalyst peroxidase, LCV is oxidized by hydrogen peroxide, forming a colored crystal violet ion (CV+, which is stable for days. The LCV method uses standard equipment and allows for detection at the low microM concentration level. Results show strong pH dependence with maximum LCV oxidation at pH 4.23. By chelating dissolved Fe(II with EDTA, hydrogen peroxide can be stabilized for analysis. Results are presented for hydrogen peroxide quantification in pyrite–water slurries. Pyrite–water slurries show surface area dependent generation of hydrogen peroxide only in the presence of EDTA, which chelates dissolved Fe(II. Given the stability of CV+, this method is particularly useful for field work that involves the detection of hydrogen peroxide.

  18. Improving Student Results in the Crystal Violet Chemical Kinetics Experiment

    Science.gov (United States)

    Kazmierczak, Nathanael; Vander Griend, Douglas A.

    2017-01-01

    Despite widespread use in general chemistry laboratories, the crystal violet chemical kinetics experiment frequently suffers from erroneous student results. Student calculations for the reaction order in hydroxide often contain large asymmetric errors, pointing to the presence of systematic error. Through a combination of "in silico"…

  19. 75 FR 27815 - Carbazole Violet Pigment 23 From China and India; Determinations

    Science.gov (United States)

    2010-05-18

    ... (Review) Carbazole Violet Pigment 23 From China and India; Determinations On the basis of the record \\1... countervailing duty order on carbazole violet pigment 23 from India would be likely to lead to continuation or... that revocation of the antidumping duty orders on carbazole violet pigment 23 from China and...

  20. 75 FR 14468 - Carbazole Violet Pigment 23 From China and India

    Science.gov (United States)

    2010-03-25

    ... COMMISSION Carbazole Violet Pigment 23 From China and India AGENCY: United States International Trade... carbazole violet pigment 23 from India and the antidumping duty orders on carbazole violet pigment 23 from China and India. SUMMARY: The Commission hereby gives notice of the scheduling of expedited...

  1. Ultra-precision bearings

    CERN Document Server

    Wardle, F

    2015-01-01

    Ultra-precision bearings can achieve extreme accuracy of rotation, making them ideal for use in numerous applications across a variety of fields, including hard disk drives, roundness measuring machines and optical scanners. Ultraprecision Bearings provides a detailed review of the different types of bearing and their properties, as well as an analysis of the factors that influence motion error, stiffness and damping. Following an introduction to basic principles of motion error, each chapter of the book is then devoted to the basic principles and properties of a specific type of bearin

  2. Different degradation behaviors of InGaN/GaN MQWs blue and violet LEDs

    Energy Technology Data Exchange (ETDEWEB)

    Huang Liubing [State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Yu Tongjun, E-mail: tongjun@pku.edu.c [State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China); Chen Zhizhong; Qin Zhixin; Yang Zhijian; Zhang Guoyi [State Key Laboratory of Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China)

    2009-12-15

    InGaN/GaN multiple quantum wells (MQWs) blue and violet light-emitting diodes (LEDs) were stressed under the injection current density of 26.5 A/cm{sup 2} for about 400 h at room temperature. Degradation behaviors of blue and violet LEDs were compared. Two stages of degradation were identified in the blue and violet LEDs. At the initial stage, the violet LEDs degraded very fast, but the blue LEDs degraded relatively slow. At later stage, both blue and violet LEDs showed similar degradation rates. Analyses of the L-I and I-V characteristics revealed that the increase of effective nonradiative recombination centers in the active regions was responsible for both blue and violet LED degradations. Rapid degradation of violet LEDs at early stage resulted from dramatical increase of the effective nonradiative centers. More indium in the MQWs might be helpful for better reliability performance of blue LEDs.

  3. Ultra and extremely low frequency electromagnetic fields

    CERN Document Server

    Surkov, Vadim

    2014-01-01

    This book examines how different sources and physical mechanisms affect ULF/ELF effects. It investigates non seismic prediction of impending natural disasters such as earthquakes, volcano eruptions and tsunamis.

  4. Photoporation and cell transfection using a violet diode laser

    Science.gov (United States)

    Paterson, L.; Agate, B.; Comrie, M.; Ferguson, R.; Lake, T. K.; Morris, J. E.; Carruthers, A. E.; Brown, C. T. A.; Sibbett, W.; Bryant, P. E.; Gunn-Moore, F.; Riches, A. C.; Dholakia, Kishan

    2005-01-01

    The introduction and subsequent expression of foreign DNA inside living mammalian cells (transfection) is achieved by photoporation with a violet diode laser. We direct a compact 405 nm laser diode source into an inverted optical microscope configuration and expose cells to 0.3 mW for 40 ms. The localized optical power density of ~1200 MW/m2 is six orders of magnitude lower than that used in femtosecond photoporation (~104 TW/m2). The beam perforates the cell plasma membrane to allow uptake of plasmid DNA containing an antibiotic resistant gene as well as the green fluorescent protein (GFP) gene. Successfully transfected cells then expand into clonal groups which are used to create stable cell lines. The use of the violet diode laser offers a new and simple poration technique compatible with standard microscopes and is the simplest method of laser-assisted cell poration reported to date.

  5. Danish Ultras

    DEFF Research Database (Denmark)

    Havelund, Jonas; Joern, Lise; Rasmussen, Kristian

    2012-01-01

    is the result of a qualitative study of the self-declared nonviolent segment of the Danish risk supporters, i.e. the ultra culture. The study’s empirical data stems from qualitative interviews and participant observation primarily focusing at matches involving Brøndby IF, the club supported by the interviewees...

  6. MORPHOLOGICAL AND CHEMICAL PROPERTIES OF SELECTED SWEET VIOLET POPULATIONS

    OpenAIRE

    Erhatić, Renata; Vukobratović, Marija; Tomislava PEREMIN VOLF; Vesna ŽIDOVEC

    2010-01-01

    Sweet violet (Viola odorata L.) blooms in continental climate conditions in early spring (March-April) with delicate flowers of attractive scent because of which it is frequently gathered from its natural habitats. Differences among the populations were established according to their morphological properties of twelve populations from Križevci area. Stated information indicates that the populations gathered from meadow – habitat are shorter and have a smaller diameter than the populations gat...

  7. How extreme are extremes?

    Science.gov (United States)

    Cucchi, Marco; Petitta, Marcello; Calmanti, Sandro

    2016-04-01

    High temperatures have an impact on the energy balance of any living organism and on the operational capabilities of critical infrastructures. Heat-wave indicators have been mainly developed with the aim of capturing the potential impacts on specific sectors (agriculture, health, wildfires, transport, power generation and distribution). However, the ability to capture the occurrence of extreme temperature events is an essential property of a multi-hazard extreme climate indicator. Aim of this study is to develop a standardized heat-wave indicator, that can be combined with other indices in order to describe multiple hazards in a single indicator. The proposed approach can be used in order to have a quantified indicator of the strenght of a certain extreme. As a matter of fact, extremes are usually distributed in exponential or exponential-exponential functions and it is difficult to quickly asses how strong was an extreme events considering only its magnitude. The proposed approach simplify the quantitative and qualitative communication of extreme magnitude

  8. Plasmas generated by ultra-violet light rather than electron impact

    Energy Technology Data Exchange (ETDEWEB)

    Franklin, R. N. [Department of Astronomy and Physics, The Open University, Milton Keynes MK7 6AA (United Kingdom); Allen, J. E. [University College, University of Oxford, Oxford OX1 4BH, United Kingdom and OCIAM, Mathematical Institute, University of Oxford, Oxford OX2 6GG (United Kingdom); Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Thomas, D. M. [Blackett Laboratory, Imperial College London, Prince Consort Road, London SW7 2BW (United Kingdom); Benilov, M. S. [Departamento de Fisica, CCCEE, Universidade de Madeira, Largo do Municipio, 9000 Funchal (Portugal)

    2013-12-15

    We analyze, in both plane and cylindrical geometries, a collisionless plasma consisting of an inner region where generation occurs by UV illumination, and an un-illuminated outer region with no generation. Ions generated in the inner region flow outwards through the outer region and into a wall. We solve for this system's steady state, first in the quasi-neutral regime (where the Debye length λ{sub D} vanishes and analytic solutions exist) and then in the general case, which we solve numerically. In the general case, a double layer forms where the illuminated and un-illuminated regions meet, and an approximately quasi-neutral plasma connects the double layer to the wall sheath; in plane geometry, the ions coast through the quasi-neutral section at slightly more than the Bohm speed c{sub s}. The system, although simple, therefore has two novel features: a double layer that does not require counter-streaming ions and electrons, and a quasi-neutral plasma where ions travel in straight lines with at least the Bohm speed. We close with a précis of our asymptotic solutions of this system, and suggest how our theoretical conclusions might be extended and tested in the laboratory.

  9. An ultrashort pulse ultra-violet radiation undulator source driven by a laser plasma wakefield accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Anania, M. P. [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); INFN, Laboratori Nazionali di Frascati, I-00044 Frascati (Italy); Brunetti, E.; Wiggins, S. M.; Grant, D. W.; Welsh, G. H.; Issac, R. C.; Cipiccia, S.; Shanks, R. P.; Manahan, G. G.; Aniculaesei, C.; Jaroszynski, D. A., E-mail: d.a.jaroszynski@strath.ac.uk [SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Geer, S. B. van der; Loos, M. J. de [Pulsar Physics, Burghstraat 47, 5614 BC Eindhoven (Netherlands); Poole, M. W.; Shepherd, B. J. A.; Clarke, J. A. [ASTeC, STFC, Daresbury Laboratory, Warrington WA4 4AD (United Kingdom); Gillespie, W. A. [SUPA, School of Engineering, Physics and Mathematics, University of Dundee, Dundee DD1 4HN (United Kingdom); MacLeod, A. M. [School of Computing and Creative Technologies, University of Abertay Dundee, Dundee DD1 1HG (United Kingdom)

    2014-06-30

    Narrow band undulator radiation tuneable over the wavelength range of 150–260 nm has been produced by short electron bunches from a 2 mm long laser plasma wakefield accelerator based on a 20 TW femtosecond laser system. The number of photons measured is up to 9 × 10{sup 6} per shot for a 100 period undulator, with a mean peak brilliance of 1 × 10{sup 18} photons/s/mrad{sup 2}/mm{sup 2}/0.1% bandwidth. Simulations estimate that the driving electron bunch r.m.s. duration is as short as 3 fs when the electron beam has energy of 120–130 MeV with the radiation pulse duration in the range of 50–100 fs.

  10. Registration of RF Plasma Radiation in Ultra-Violet Range by Solar-blind Photoreceptor

    Science.gov (United States)

    Nguyen-Kuok, Shi; Malakhov, Yury; Korotkikh, Ivan

    2016-09-01

    A spectrum response of a photoreceptor to the RF plasma radiation is determined in the present work by means of a spectrophotometer utilizing a gas-filled photoreceptor. A continuous radiation spectrum was observed in the wavelength interval of 190 - 270 nm. The photoreceptor allows measuring of absolute radiation taking into account the spectral sensitivity of the photoreceptor and the values of quantum output for the given wavelength. A continuous spectrum was observed in all three orders of magnitude of diffraction. Develop and test a technique for measuring the intensity of the plasma radiation in the UV wavelength range measured amount of discharge pulses can be used to determine the spectral sensitivity range of UV radiation receivers. Professor.

  11. Zwitterionic states in gas-phase polypeptide ions revealed by 157-nm ultra-violet photodissociation

    DEFF Research Database (Denmark)

    Kjeldsen, Frank; Silivra, Oleg A; Zubarev, Roman A

    2006-01-01

    carboxylic groups relative to competing COOH losses (45 Da) from neutral carboxylic groups. Loss of CO2 is a strong indication of the presence of a zwitterionic [(+)...(-)...(+)] salt bridge in the gas-phase polypeptide cation. This method provides a tool for studying, for example, the nature of binding...

  12. Quantitative Detection of Combustion Species using Ultra-Violet Diode Lasers

    Science.gov (United States)

    Pilgrim, J. S.; Peterson, K. A.

    2001-01-01

    Southwest Sciences is developing a new microgravity combustion diagnostic based on UV diode lasers. The instrument will allow absolute concentration measurements of combustion species on a variety of microgravity combustion platforms including the Space Station. Our approach uses newly available room temperature UV diode lasers, thereby keeping the instrument compact, rugged and energy efficient. The feasibility of the technique was demonstrated by measurement of CH radicals in laboratory flames. Further progress in fabrication technology of UV diode lasers at shorter wavelengths and higher power will result in detection of transient species in the deeper UV. High sensitivity detection of combustion radicals is provided with wavelength modulation absorption spectroscopy.

  13. Effect Of Ethylene Oxide, Autoclave and Ultra Violet Sterilizations On Surface Topography Of Pet Electrospun Fibers

    Directory of Open Access Journals (Sweden)

    Sebnem DUZYER

    2016-11-01

    Full Text Available The aim of this study to investigate the effects of different sterilization methods on electrospun polyester. Ethylene oxide (EO, autoclave (AU and ultraviolet (UV sterilization methods were applied to electrospun fibers produced from polyethylene terephthalate (PET solutions with concentrations of 10, 15 and 20 wt.%. The surface characteristics of the fibers were examined by scanning electron microscope (SEM, atomic force microscope (AFM, surface pore size studies and contact angle measurements. Differential scanning calorimetry (DSC tests were carried out to characterize the thermal properties. Fourier Transform Infrared spectroscopy (FTIR tests were performed to analyze the micro structural properties. SEM studies showed that different sterilization methods made significant changes on the surfaces of the fibers depending on the PET concentration. Although the effects were decreased with the increasing polymer concentration, the fiber structure was damaged especially with the EO sterilization. The contact angle values were decreased with the UV sterilization method the most.

  14. Leading and following sunspots: their magnetic properties and ultra-violet emission above them

    CERN Document Server

    Zagainova, Iu S; Obridko, V N

    2015-01-01

    Using SDO/HMI and SDO/AIA data for sunspot groups of the 24th solar cycle, we analyzed magnetic properties and He II 304 emission in leading and following sunspots separately. Simultaneous examination of umbral magnetic properties and atmospheric characteristics above the umbrae draws on average differences in He II 304 contrast over the umbrae of leading and following spots we discovered earlier for solar cycle 23 sunspot groups based on SOHO data as well as on the hypothetical relationship between contrast asymmetry and magnetic field asymmetry in umbrae. We use a more accurate and faster algorithm for solving the pi-uncertainty problem of the transverse magnetic field direction in this research producing new results on differences in magnetic field properties between magneto-conjugated leaders and followers. We found that, in ~78% of the cases, the minimum (over the umbra area) angle between the magnetic field line and the normal to the solar surface, a_min, is smaller in the leading spots, so the magnetic...

  15. Physical-Mechanical Properties of Nitrodopes Affected by Ultra-Violet Radiation

    Directory of Open Access Journals (Sweden)

    Miodrag Stojanovic

    2007-10-01

    Full Text Available The FTIR spectroscopy has been employed in this research work to monitor theprocess of nitrodope photodegradation, by measuring surfaces of bands typical of a nitrogroup. Nitric esters are subject to degradation, which is reflected on a quantitative ratio ofthe surfaces of the IR bands that originate from the nitric ester. The obtained results showthat the length of the UV rays’ activity on the samples over the time periods of 240, 480and 960 minutes directly affects the spectrum appearance of the same sample before andafter the irradiation. The longer the action time of the UV rays and the higher a masspercentage of nitrocellulose in the nitrodope is, the smaller the bands’ surfaces become, i.e.the level of degradation is higher. In order to confirm the degradation of nitrodope, thedegree of crosslinking has also been examined by determining the König hardness and alsothe mean viscosity molar mass has been defined repeatedly applying the capillaryviscosimetry method.

  16. Ultra-violet Spectrophotometric Determination of Caffeine in Soft and Energy Drinks Available in Yenagoa, Nigeria

    Directory of Open Access Journals (Sweden)

    Amos-Tautua

    2014-02-01

    Full Text Available This study was carried out to determine the pH and levels of caffeine in eight brands of carbonated and energy drinks available in local market in Yenagoa, Nigeria. Quantitative analysis of caffeine was performed by a simple and fast standard UV spectrophotometric method, using carbon tetrachloride as the extracting solvent. Results showed that the pH of the beverages were slightly acidic ranging from 5.92-6.44. The minimum caffeine level was observed in the carbonated soft drink Coca Cola (43.71±0.55 ppm, while the energy drink, Red Bull sample showed the highest caffeine content (58.31±0.35 ppm. The carbonated soft drinks showed caffeine levels in the range of 43.71 and 45.83 ppm with average concentration of 44.52 ppm, whereas in the energy drinks it ranged from 47.56 to 58.31 ppm with a mean concentration of 52.24 ppm. The caffeine content in all the beverage samples analyzed in this study are well below the maximum allowable limits set by the US Food and Drugs Administration.

  17. Effects of agrochemicals, ultra violet stabilisers and solar radiation on the radiometric properties of greenhouse films

    Directory of Open Access Journals (Sweden)

    Giuliano Vox

    2013-10-01

    Full Text Available Agrochemicals, based on iron, sulphur and chlorine, generate by products that lead to a degradation of greenhouse films together with a decrease in their mechanical and physical properties. The degradation due to agrochemicals depends on their active principles, method and frequency of application, and greenhouse ventilation. The aim of the research was to evaluate how agrochemical contamination and solar radiation influence the radiometric properties of ethylene-vinyl acetate copolymer greenhouse films by means of laboratory and field tests. The films, manufactured on purpose with the addition of different light stabiliser systems, were exposed to natural outdoor weathering at the experimental farm of the University of Bari (Italy; 41° 05’ N in the period from 2006 to 2008. Each film was tested for two low tunnels: one low tunnel was sprayed from inside with the agrochemicals containing iron, chlorine and sulphur while the other one was not sprayed and served as control. Radiometric laboratory tests were carried out on the new films and on samples taken at the end of the trials. The experimental tests showed that both the natural weathering together with the agrochemicals did not modify significantly the radiometric properties of the films in the solar and in the photosynthetically active radiation wavelength range. Within six months of experimental field tests the variations in these radiometric characteristics were at most 10%. Significant variations, up to 70% of the initial value, were recorded for the stabilised films in the long-wave infrared radiation wavelength range.

  18. Formation of genotoxic compounds by medium pressure ultra violet treatment of nitrate rich water

    NARCIS (Netherlands)

    Martijn, A.J.; Boersma, M.G.; Vervoort, Jacques; Rietjens, I.; Kruithof, J.C.

    2014-01-01

    Genotoxic compounds were produced by full-scale medium pressure (MP) ultraviolet hydrogen peroxide (UV/H2O2) treatment of nitrate-rich pretreated surface water. It was hypothesized that this formation was caused by the reaction of nitrate photolysis intermediates with natural organic matter (NOM). A

  19. Properties of Ultra-Violet Cured Poly(diemthylsiloxane)-Urea Acrylates.

    Science.gov (United States)

    1984-11-01

    fraction. 2. Infrared Spectroscopy The thin polymer films were cast on KBr plates and infrared spectra were taken before and after UV irradiation using a...synthesized by coequilibration of octamethylcyclotetraslloxane (U4) (Petrarch Systems Inc.) and 1,3,bis(-y-aminopropyl)tetramethyldisiloxane (AT) ( Silar ...viscoelastoer model DDV-IIC which was controlled automatically. by a LSI-11/03 microprocessor. Film samples of about 20x3xO.04 mm in size were tested

  20. A Fourier transform spectrometer for visible and near ultra-violet measurements of atmospheric absorption

    Science.gov (United States)

    Parsons, C. L.; Gerlach, J. C.; Whitehurst, M.

    1982-01-01

    The development of a prototype, ground-based, Sun-pointed Michelson interferometric spectrometer is described. Its intended use is to measure the atmospheric amount of various gases which absorb in the near-infrared, visible, and near-ultraviolet portions of the electromagnetic spectrum. Preliminary spectra which contain the alpha, 0.8 micrometer, and rho sigma tau water vapor absorption bands in the near-infrared are presented to indicate the present capability of the system. Ultimately, the spectrometer can be used to explore the feasible applications of Fourier transform spectroscopy in the ultraviolet where grating spectrometers were used exclusively.

  1. Ultra Violet Escape Fractions from Giant Molecular Clouds During Early Cluster Formation

    CERN Document Server

    Howard, Corey S; Klessen, Ralf S

    2016-01-01

    The UV photon escape fraction from molecular clouds is a key parameter for understanding the ionization of the Interstellar Medium (ISM), and extragalactic processes, such as cosmic reionization. We present the ionizing photon flux and the corresponding photon escape fraction (f$_{esc}$) arising as a consequence of star cluster formation in a turbulent, 10$^6$ M$_{\\odot}$ GMC, simulated using the code FLASH. We make use of sink particles to represent young, star-forming clusters coupled with a radiative transfer scheme to calculate the emergent UV flux. We find that the ionizing photon flux across the cloud boundary is highly variable in time and space due to the turbulent nature of the intervening gas. The escaping photon fraction remains at $\\sim$5% for the first 2.5 Myr, followed by two pronounced peaks at 3.25 and 3.8 Myr with a maximum f$_{esc}$ of 30% and 37%, respectively. These peaks are due to the formation of large HII regions, that expand into regions of lower density and some of which reach the cl...

  2. STUDY OF INTERACTION OF DRUGS WITH BODY-ALIKE MACROMOLECULE (POLYVINYLPYRROLIDONE BY ULTRA VIOLET SPECTROSCOPIC METHOD

    Directory of Open Access Journals (Sweden)

    AKHTAR SAEED

    2006-01-01

    Full Text Available UV-visible spectrophotometric technique was used to study the interaction of polyvinylpyrrolidone (PVP with co-solutes: phenol, benzoic acid, sodium benzoate, salicylic acid and acetyl salicylic acid in aqueous medium. Changes in the absorption spectra of the co-solutes were observed in the presence of PVP from 200 to 210 nm. The changes were attributed to interaction of PVP molecules with the co-solute molecules. As the concentration of the co-solute increased, a red shift in the bands was observed indicating an increase in interaction between PVP and the co-solute.

  3. Engineering of ultra-violet ray curable PSAs%UV固化压敏胶工程

    Institute of Scientific and Technical Information of China (English)

    吕凤亭

    2012-01-01

    压敏胶及其制品工业需要向节能、减排、绿色方面发展.其中以UV固化压敏胶制品的工业化最为先进.UV固化压敏胶工业化,即UV固化压教胶工程分为4部分予以实现:1)UV固化压敏胶制备;2)UV固化辐照设备设计;3)UV固化压敏胶涂布生产线的建造和改造;4)工厂管理和成本测算.%Pressure-sensitive adhesive products industry needs to save energy,reduce emission and realize green. Wherein,the industrialization of the UV curable PSA products is the most prominent.The industrialization, that is the engineering, of the UV curable PSAs is divided into four sections: 1. The preparation of the UV curable PSAs,2. The designment of UV radiation devices,3. The construction and modification of coating production line,and,4.the factory management and the cost estimates.

  4. Growth and properties of ultra-violet emitting aligned zinc oxide nanocones with hexagonal caps.

    Science.gov (United States)

    Umar, Ahmad; Al Hajry, A; Al-Ghamdi, A A; Al-Heniti, S

    2010-10-01

    Ultraviolet-emitting, single-crystalline aligned zinc oxide (ZnO) nanocones with hexagonal caps were grown on silicon substrate via simple non-catalytic thermal evaporation process. High-purity metallic zinc powder and oxygen were used as source materials for zinc and oxygen, respectively. The detailed structural characterizations confirmed that the formed products are single-crystalline, possess a wurtzite hexagonal phase and grown along the c-axis direction. Raman-active optical-phonon E2(high) mode at 437 cm(-1) with sharp and strong UV emission at 385 nm in room-temperature photoluminescence (PL) spectrum demonstrated that the as-grown ZnO nanocones with hexagonal caps possess good-crystal quality with the excellent optical properties. Finally, a plausible growth mechanism for the formation of as-grown ZnO nanocones with hexagonal caps was also proposed.

  5. Thermal annealing effects on ultra-violet luminescence properties of Gd doped AlN

    Energy Technology Data Exchange (ETDEWEB)

    Kita, Takashi; Ishizu, Yuta; Tsuji, Kazuma; Harada, Yukihiro [Department of Electrical and Electronic Engineering, Graduate School of Engineering, Kobe University, 1-1 Rokkodai, Nada, Kobe 657-8501 (Japan); Chigi, Yoshitaka; Nishimoto, Tetsuro; Tanaka, Hiroyuki; Kobayashi, Mikihiro [YUMEX INC., 400 Itoda, Yumesaki, Himeji, Hyogo 671-2114 (Japan); Ishihara, Tsuguo; Izumi, Hirokazu [Hyogo Prefectural Institute of Technology, 3-1-12 Yukihira, Suma, Kobe 654-0037 (Japan)

    2015-04-28

    We studied energy transfer from AlN to doped Gd{sup 3+} ions as a function of the post-thermal annealing temperature. Gd-doped AlN thin films were deposited on fused-silica substrates using a reactive radio-frequency magnetron sputtering technique. The film is a c-axis oriented polycrystal. The intra-orbital electron transition in Gd{sup 3+} showed an atomically sharp luminescence at 3.9 eV (318 nm). The photoluminescence (PL) excitation spectrum exhibited a resonant peak, indicating efficient energy transfer from the host AlN crystal to Gd{sup 3+} ions. The PL intensity increases approximately ten times by thermal annealing. The PL decay lifetime becomes long with annealing, and mid-gap luminescence relating to the crystal defects in AlN was also found to be reduced by annealing. These results suggest that energy dissipation of excited carriers in AlN was suppressed by annealing, and the efficiency of energy transfer into Gd{sup 3+} was improved.

  6. Induction of gynogenetic haploidy in oyster Crassostrea gigas, using ultra violet irradiated sperms

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, U.

    Eggs of Crassostrea gigas were fertilized with sperms exposed to different doses of UV irradiations by keeping a constant rate of 121.47 ergs. mm/2 sec/1 and changing the period of exposure from 4 to 90 sec. Samples of larvae were analysed...

  7. The Young and the Dustless: Interpreting Radio Observations of UltraViolet Luminous Galaxies

    CERN Document Server

    Basu-Zych, Antara R; Johnson, Benjamin D; Hoopes, Charles; Overzier, Roderik; Treyer, Marie A; Heckman, Timothy M; Barlow, Tom A; Bianchi, Luciana; Conrow, Tim; Donas, Jose; Forster, Karl G; Friedman, Peter G; Lee, Young-Wook; Madore, Barry F; Martin, D Christopher; Milliard, Bruno; Morrissey, Patrick; Neff, Susan G; Rich, R Michael; Salim, Samir; Seibert, Mark; Small, Todd A; Szalay, Alexander S; Wyder, Ted K; Yi, Suk Young

    2007-01-01

    Ultraviolet Luminous Galaxies (UVLGs) have been identified as intensely star-forming, nearby galaxies. A subset of these, the supercompact UVLGs, are believed to be local analogs of high redshift Lyman Break Galaxies. Here we investigate the radio continuum properties of this important population for the first time. We have observed 42 supercompact UVLGs with the VLA, all of which have extensive coverage in the UV/optical by GALEX and SDSS. Our analysis includes comparison samples of multiwavelength data from the Spitzer First Look Survey and from the SDSS-Galex matched catalogs. In addition we have Spitzer MIPS data for 24 of our galaxies and find that they fall on the radio-FIR correlation of normal star-forming galaxies. We find that our galaxies have lower radio-to-UV ratios and lower Balmer decrements than other local galaxies with similar (high) star formation rates. Optical spectra show they have lower Dn(4000) and HdeltaA indices, higher Hbeta emission-line equivalents widths, and higher [OIII]5007/Hb...

  8. Sulphur Dioxide: High Resolution Ultra-Violet Photoabsorption Cross Section Measurements at 200K.

    Science.gov (United States)

    Blackie, D.; Blackwell-Whitehead, R.; Stark, G.; Pickering, J. C.; Rufus, J.; Thorne, A.; Smith, P. L.

    2007-12-01

    Sulphur Dioxide plays an important role not only within the Earth's atmosphere but also within the complex chemistry of both the upper atmosphere of Venus and the volcanically active Jovian moon Io. The lack of high resolution laboratory studies has prevented the full, accurate determination of absorption cross sections which are the basis for reliable photochemical models. High resolution laboratory measurements of SO2 are essential to resolve the complex SO2 spectrum and yield accurate photoabsorption cross sections. Using the Imperial College UV Fourier Transform Spectrometer new high resolution (λ/δλ ~ 450,000) measurements have been recorded over a range of temperatures and pressures. As part of an on-going series of measurements, current laboratory work focused on photoabsorption cross sections of SO2 at 200K across the wavelength range 220 → 325 nm. These measurements not only compliment previous room temperature measurements obtained at Imperial College in the 190 → 220 nm and 220 → 328 nm ranges (Stark et al., JGR Planets 104, 16, 585 (1999) and Rufus et al.,( JGR Planets 108, 2, 5 (2003)), but also coincide with the wavelength regions being recorded by the Venus Express mission through the UV-IR spectrometer SPICAV (ESA-SCI(2001)6). Our new measurements will allow accurate analysis of the chemical processes in the upper atmosphere of Venus. These absorption cross section measurements are the first to be acquired at this resolution, temperature and pressure. Results will be presented. This work was supported in part by NASA Grant NNG05GA03G, PPARC (UK), and the Leverhulme Trust.

  9. Print characterization of photomasks from next-generation deep-ultra-violet laser pattern generator

    Science.gov (United States)

    Jackson, Curt; Kiefer, Robert; Buck, Peter; Mellenthin, David; Manfredo, John; Garg, Vishal; Hickethier, Jason; Cohen, Sarah; Morgante, Cris; Allen, Paul C.; Christenson, Eric; White, Michael

    2005-06-01

    Currently, the ALTA 4300 generation DUV Laser tool is capable of printing critical and semi-critical photomasks for the 130nm and 90nm IC technology nodes. With improved optical elements, an improved objective lens, and a higher bandwidth data-path the capability of the tool has been dramatically enhanced - culminating with the introduction of the ALTA 4700. Both the ALTA 4300 system"s diffractive optic element (DOE) and acousto-optic modulator (AOM) have been refined. Additionally, the ALTA 4300 system"s 33x, 0.8NA objective lens has been replaced with a 42x, 0.9NA objective lens. Finally, the tool"s data-path has been enhanced to maintain the ALTA system"s superior write time on critical mask layers. Quantitative results of these enhancements will be detailed through reporting of critical feature resolution limits, CD uniformity control, and pattern placement accuracy on mask. Performance will be shown from masks printed pre- and post- hardware upgrade. Experimental results will be compared with theoretical calculations that show expected and actual improvements. In this paper details of the aerial image created when printing wafers with DUV Laser generated photomasks pre- and post- upgrade will be shown. 193nm print results will be shown with multiple illumination conditions. Details of a print test comparison performed on photomasks from each tool configuration will be documented. The print test comparison will include process window characterization from each mask type.

  10. EUV SpectroPhotometer (ESP) in Extreme Ultraviolet Variability Experiment (EVE): Algorithms and Calibrations

    Science.gov (United States)

    Didkovsky, L.; Judge, D.; Wieman, S.; Woods, T.; Jones, A.

    2012-01-01

    The Extreme ultraviolet SpectroPhotometer (ESP) is one of five channels of the Extreme ultraviolet Variability Experiment (EVE) onboard the NASA Solar Dynamics Observatory (SDO). The ESP channel design is based on a highly stable diffraction transmission grating and is an advanced version of the Solar Extreme ultraviolet Monitor (SEM), which has been successfully observing solar irradiance onboard the Solar and Heliospheric Observatory (SOHO) since December 1995. ESP is designed to measure solar Extreme UltraViolet (EUV) irradiance in four first-order bands of the diffraction grating centered around 19 nm, 25 nm, 30 nm, and 36 nm, and in a soft X-ray band from 0.1 to 7.0 nm in the zeroth-order of the grating. Each band’s detector system converts the photo-current into a count rate (frequency). The count rates are integrated over 0.25-second increments and transmitted to the EVE Science and Operations Center for data processing. An algorithm for converting the measured count rates into solar irradiance and the ESP calibration parameters are described. The ESP pre-flight calibration was performed at the Synchrotron Ultraviolet Radiation Facility of the National Institute of Standards and Technology. Calibration parameters were used to calculate absolute solar irradiance from the sounding-rocket flight measurements on 14 April 2008. These irradiances for the ESP bands closely match the irradiance determined for two other EUV channels flown simultaneously: EVE’s Multiple EUV Grating Spectrograph (MEGS) and SOHO’s Charge, Element and Isotope Analysis System/ Solar EUV Monitor (CELIAS/SEM).

  11. Computer-to-plate Technology: Violet or Thermo?

    OpenAIRE

    Michael Mittelhaus

    2004-01-01

    Up to now CtP has been a technology for medium-sized and large companies and their printing presses, and thus predominantly in the 70 x 100 cm format and larger. The CtP technology is and remains divided up between violet and thermo, with the advantages and drawbacks of both imaging systems in a counterbalance. Due to the broad penetration of CtP in many markets, practical questions have now come to the fore, including those of continuous process control and quality assurance; providers and s...

  12. MORPHOLOGICAL AND CHEMICAL PROPERTIES OF SELECTED SWEET VIOLET POPULATIONS

    Directory of Open Access Journals (Sweden)

    Renata ERHATIĆ

    2010-10-01

    Full Text Available Sweet violet (Viola odorata L. blooms in continental climate conditions in early spring (March-April with delicate flowers of attractive scent because of which it is frequently gathered from its natural habitats. Differences among the populations were established according to their morphological properties of twelve populations from Križevci area. Stated information indicates that the populations gathered from meadow – habitat are shorter and have a smaller diameter than the populations gathered from the habitat in forest, whereas the population from the orchards has the highest number of leaves and flowers. Correlation analysis shows strong (P<0.01 positive connection of the root mass, leaves mass, number of leaves with the total mass of the plants, as well as connection of the plant mass with the number of flowers. Chemical analysis established agrochemical soil properties and nutrient concentrations in plants. Correlations between the examined properties of violets and soil properties indicate that the potassium concentration in the roots is in strong (P <0.01 correlation with potassium in the soil, whereas phosphorus concentration in flower is in a considerably strong (P<0.05 positive correlation with the phosphorus in the soil.

  13. Extreme Makeover

    Institute of Scientific and Technical Information of China (English)

    VALERIE; SARTOR

    2008-01-01

    Sir Norman Foster’s architecturefirm, in conjunction with theBeijing Institute of ArchitecturalDesign and Research, recently fin-ished the dazzling, ultra-modern Terminal3 at the Beijing Capital International

  14. Investigation of adsorption of the dyestuff astrazon red violet 3rn (basic violet 16 on montmorillonite clay

    Directory of Open Access Journals (Sweden)

    B. A. Fil

    2014-03-01

    Full Text Available In this study, color removal by absorption from synthetically prepared wastewater was investigated using montmorillonite clay by adsorption. As dyestuff Astrazon Red Violet 3RN (Basic Violet 16 was used. Experimental parameters selected were pH, temperature, agitation speed, initial dyestuff concentration, adsorbent dosage and ionic strength. It was established that adsorption rate increased with increasing pH, temperature, dye concentration and agitation speed, but decreased with increased ionic strength and adsorbent dosage. Adsorption equilibrium data obtained by a series of experiments carried out in a water bath were employed with common isotherm equations such as Langmuir, Freundlich, Temkin, Elovich and Dubinin-Radushkevich. It was found that the Langmuir equation appears to fit the equilibrium data better than the other models. Furthermore, the fit of the kinetic data to common kinetic models such as the pseudo-first-order, second-order, Elovich and intraparticle diffusion models was tested to elucidate the adsorption mechanism. Kinetic data conformed to the pseudo-second-order model, indicating chemisorptions. In addition, the thermodynamic parameters activation energy, Ea, enthalpy ΔH*, entropy, ΔS*, and free energy change, ΔG*, were calculated. The values of the calculated parameters indicated that physical adsorption of ARV on the clay was dominant and that the adsorption process was endothermic.

  15. Quantification of biofilm biomass by staining: Non-toxic safranin can replace the popular crystal violet.

    Science.gov (United States)

    Ommen, Pernille; Zobek, Natalia; Meyer, Rikke Louise

    2017-10-01

    Crystal violet staining is commonly used for quantification of biofilm formation, although it is highly toxic. Here we test safranin as a non-toxic replacement. Safranin staining provided similar results as crystal violet, but with higher reproducibility. We therefore recommend safranin staining for biofilm biomass quantification. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. A milestone toward understanding PDR properties in the extreme environment of LMC-30Dor

    CERN Document Server

    Chevance, M; Lebouteiller, V; Godard, B; Cormier, D; Galliano, F; Hony, S; Indebetouw, R; Bourlot, J Le; Lee, M Y; Petit, F Le; Pellegrini, E; Roueff, E; Wu, R

    2016-01-01

    More complete knowledge of galaxy evolution requires understanding the process of star formation and interaction between the interstellar radiation field and the interstellar medium in galactic environments traversing a wide range of physical parameter space. Here we focus on the impact of massive star formation on the surrounding low metallicity ISM in 30 Doradus in the Large Magellanic Cloud. A low metal abundance, as is the case of some galaxies of the early universe, results in less ultra-violet shielding for the formation of the molecular gas necessary for star formation to proceed. The half-solar metallicity gas in this region is strongly irradiated by the super star cluster R136, making it an ideal laboratory to study the structure of the ISM in an extreme environment. Our spatially resolved study investigates the gas heating and cooling mechanisms, particularly in the photo-dissociation regions where the chemistry and thermal balance are regulated by far-ultraviolet photons (6 eV< h\

  17. Transient transfection of mammalian cells using a violet diode laser

    Science.gov (United States)

    Torres-Mapa, Maria Leilani; Angus, Liselotte; Ploschner, Martin; Dholakia, Kishan; Gunn-Moore, Frank J.

    2010-07-01

    We demonstrate the first use of the violet diode laser for transient mammalian cell transfection. In contrast to previous studies, which showed the generation of stable cell lines over a few weeks, we develop a methodology to transiently transfect cells with an efficiency of up to ~40%. Chinese hamster ovary (CHO-K1) and human embryonic kidney (HEK293) cells are exposed to a tightly focused 405-nm laser in the presence of plasmid DNA encoding for a mitochondrial targeted red fluorescent protein. We report transfection efficiencies as a function of laser power and exposure time for our system. We also show, for the first time, that a continuous wave laser source can be successfully applied to selective gene silencing experiments using small interfering RNA. This work is a major step towards an inexpensive and portable phototransfection system.

  18. The response characteristics of tetrazolium violet solutions to gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Emi-Reynolds, G. [Radiation Protection Institute, Ghana Atomic Energy Commission, P.O. Box LG 80, Legon-Accra (Ghana)]. E-mail: gemi-reynolds@idngh.com; Kovacs, Andras [Institute of Isotopes, Hungarian Academy of Sciences, P.O. Box 77, Budapest H-1525 (Hungary); Fletcher, J.J. [Department of Physics, University of Cape Coast, Cape Coast (Ghana)

    2007-08-15

    The dosimetry characteristics of various solutions of tetrazolium violet, TV, (2,5-diphenyl-3-(1-naphthyl)-2H-tetrazolium chloride) to gamma irradiation are reported. The optical absorption spectra of these solutions show peaks between 400 and 600 nm with a shoulder at around 550 nm. The dose response of the optical absorbance values of aqueous and aqueous-alcoholic solutions containing different concentrations of TV was measured in the 250 Gy up to 75 kGy dose range. The formation of formazan product was observed due to radiolytic reduction in both solutions. Its formation was found more pronounced in N{sub 2}-saturated as well as in alkaline solutions. The results indicate that the 1 mM TV solution can be used for food irradiation and medical sterilization dosimetry at gamma irradiation facilities.

  19. The response characteristics of tetrazolium violet solutions to gamma irradiation

    Science.gov (United States)

    Emi-Reynolds, G.; Kovács, András; Fletcher, J. J.

    2007-08-01

    The dosimetry characteristics of various solutions of tetrazolium violet, TV, (2,5-diphenyl-3-(1-naphthyl)-2H-tetrazolium chloride) to gamma irradiation are reported. The optical absorption spectra of these solutions show peaks between 400 and 600 nm with a shoulder at around 550 nm. The dose response of the optical absorbance values of aqueous and aqueous-alcoholic solutions containing different concentrations of TV was measured in the 250 Gy up to 75 kGy dose range. The formation of formazan product was observed due to radiolytic reduction in both solutions. Its formation was found more pronounced in N 2-saturated as well as in alkaline solutions. The results indicate that the 1 mM TV solution can be used for food irradiation and medical sterilization dosimetry at gamma irradiation facilities.

  20. Extreme Heat

    Science.gov (United States)

    ... Landslides & Debris Flow Nuclear Blast Nuclear Power Plants Power Outages Pandemic Radiological Dispersion Device Severe Weather Snowstorms & Extreme ... Landslides & Debris Flow Nuclear Blast Nuclear Power Plants Power Outages Pandemic Radiological Dispersion Device Severe Weather Snowstorms & Extreme ...

  1. Extreme Photonics & Applications

    CERN Document Server

    Hall, Trevor J; Paredes, Sofia A

    2010-01-01

    "Extreme Photonics & Applications" arises from the 2008 NATO Advanced Study Institute in Laser Control & Monitoring in New Materials, Biomedicine, Environment, Security and Defense. Leading experts in the manipulation of light offered by recent advances in laser physics and nanoscience were invited to give lectures in their fields of expertise and participate in discussions on current research, applications and new directions. The sum of their contributions to this book is a primer for the state of scientific knowledge and the issues within the subject of photonics taken to the extreme frontiers: molding light at the ultra-finest scales, which represents the beginning of the end to limitations in optical science for the benefit of 21st Century technological societies. Laser light is an exquisite tool for physical and chemical research. Physicists have recently developed pulsed lasers with such short durations that one laser shot takes the time of one molecular vibration or one electron rotation in an ...

  2. Toxicity induced by Basic Violet 14, Direct Red 28 and Acid Red 26 in zebrafish larvae.

    Science.gov (United States)

    Shen, Bing; Liu, Hong-Cui; Ou, Wen-Bin; Eilers, Grant; Zhou, Sheng-Mei; Meng, Fan-Guo; Li, Chun-Qi; Li, Yong-Quan

    2015-12-01

    Basic Violet 14, Direct Red 28 and Acid Red 26 are classified as carcinogenic dyes in the European textile ecology standard, despite insufficient toxicity data. In this study, the toxicity of these dyes was assessed in a zebrafish model, and the underlying toxic mechanisms were investigated. Basic Violet 14 and Direct Red 28 showed acute toxicity with a LC50 value at 60.63 and 476.84 µg ml(-1) , respectively, whereas the LC50 of Acid Red 26 was between 2500 and 2800 µg ml(-1) . Treatment with Basic Violet 14, Direct Red 28 and Acid Red 26 resulted in common developmental abnormalities including delayed yolk sac absorption and swimming bladder deflation. Hepatotoxicity was observed in zebrafish treated with Basic Violet 14, and cardiovascular toxicity was found in zebrafish treated with Acid Red 26 at concentrations higher than 2500 µg ml(-1) . Basic Violet 14 also caused significant up-regulation of GCLC gene expression in a dose-dependent manner whereas Acid Red 26 induced significant up-regulation of NKX2.5 and down-regulation of GATA4 at a high concentration in a dose-dependent manner. These results suggest that Basic Violet 14, Direct Red 28 and Acid Red 26 induce developmental and organ-specific toxicity, and oxidative stress may play a role in the hepatotoxicity of Basic Violet 14, the suppressed GATA4 expression may have a relation to the cardiovascular toxicity of Acid Red 26. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Mandelbrot's Extremism

    NARCIS (Netherlands)

    Beirlant, J.; Schoutens, W.; Segers, J.J.J.

    2004-01-01

    In the sixties Mandelbrot already showed that extreme price swings are more likely than some of us think or incorporate in our models.A modern toolbox for analyzing such rare events can be found in the field of extreme value theory.At the core of extreme value theory lies the modelling of maxima

  4. MORPHOGENESIS AND DEVELOPMENTAL BIOLOGY OF AFRICAN VIOLET (SAINTPAULIA IONANTHA H. WENDL.

    Directory of Open Access Journals (Sweden)

    Jaime A. TEIXEIRA DA SILVA

    2016-12-01

    Full Text Available African violet (Saintpaulia ionantha H. Wendl. has been domesticated, bred and commercialized. It is the most famous and popular of the Saintpaulia species, its ornamental value arising from its attractive leaves and flowers. African violet plants are easy to propagate by adventitious organ regeneration and are very sensitive to environmental factors including light, temperature, humidity, CO2 concentration and photoperiod. This review offers a short synthesis on advances made in conventional vegetative propagation by adventitious organ regeneration, select early historical in vitro developmental perspectives, and vegetative and reproductive development of African violet.

  5. Removal of Azo Dyes (Violet B and Violet 5R from Aqueous Solution Using New Activated Carbon Developed from Orange Peel

    Directory of Open Access Journals (Sweden)

    Saeedeh Hashemian

    2013-01-01

    Full Text Available Activated carbon developed from agricultural waste orange peel (COP was prepared. COP was characterized using Fourier infrared spectroscopy (FTIR, X-ray powder diffraction (XRD, scanning electron microscopy (SEM, and BET. COP has surface area and mean pore diameter of 225.6 m2 g−1 and 22.40 nm, respectively. The removal of violet B (VB and violet 5R (V5R from aqueous solutions by COP was investigated. The effect of operational parameters such as contact time, pH, initial dye concentration, and adsorbent dosage on the adsorption of dyes was investigated. Maximum dye was removed within 30 min of contact time at pH > 7. Two common models, the Langmuir and Freundlich isotherms, were used to investigate the interaction of dye and COPs. The isotherm evaluations revealed that the Langmuir model provides better fit to the experimental data than the Freundlich model. The adsorption of VB and V5R onto COP was followed by pseudo-second-order kinetic model with a good correlation (R2>0.99. Activation energies 5.47 and 29.7 KJ mol−1 were determined for violet B and violet 5R, respectively. The rate of adsorption of violet 5R was faster than that of violet B (kV5R>kVB. The prepared COP could thus be used as promising adsorbent for removal of organic dyes, especially azo dye, from polluted water. The solid COP could be conveniently regenerated after adsorption.

  6. Avian ultraviolet/violet cones identified as probable magnetoreceptors.

    Directory of Open Access Journals (Sweden)

    Christine Niessner

    Full Text Available BACKGROUND: The Radical-Pair-Model postulates that the reception of magnetic compass directions in birds is based on spin-chemical reactions in specialized photopigments in the eye, with cryptochromes discussed as candidate molecules. But so far, the exact subcellular characterization of these molecules in the retina remained unknown. METHODOLOGY/PRINCIPAL FINDINGS: We here describe the localization of cryptochrome 1a (Cry1a in the retina of European robins, Erithacus rubecula, and domestic chickens, Gallus gallus, two species that have been shown to use the magnetic field for compass orientation. In both species, Cry1a is present exclusively in the ultraviolet/violet (UV/V cones that are distributed across the entire retina. Electron microscopy shows Cry1a in ordered bands along the membrane discs of the outer segment, and cell fractionation reveals Cry1a in the membrane fraction, suggesting the possibility that Cry1a is anchored along membranes. CONCLUSIONS/SIGNIFICANCE: We provide first structural evidence that Cry1a occurs within a sensory structure arranged in a way that fulfils essential requirements of the Radical-Pair-Model. Our findings, identifying the UV/V-cones as probable magnetoreceptors, support the assumption that Cry1a is indeed the receptor molecule mediating information on magnetic directions, and thus provide the Radical-Pair-Model with a profound histological background.

  7. Computer-to-plate Technology: Violet or Thermo?

    Directory of Open Access Journals (Sweden)

    Michael Mittelhaus

    2004-12-01

    Full Text Available Up to now CtP has been a technology for medium-sized and large companies and their printing presses, and thus predominantly in the 70 x 100 cm format and larger. The CtP technology is and remains divided up between violet and thermo, with the advantages and drawbacks of both imaging systems in a counterbalance. Due to the broad penetration of CtP in many markets, practical questions have now come to the fore, including those of continuous process control and quality assurance; providers and specialist forums on these topics will also hold centre stage at drupa. This applies equally to frequency-modulated screening processes, which are today well known and are viewed as a means for ensuring a competitive edge. The CtP technology is now broader and more diverse than ever, and drupa 2004 will clarify which technology and which imagers best allow economical digital plate production for formats up to 50 x 70 cm.

  8. Fenton Oxidation of Methyl Violet in Aqueous Solution

    Directory of Open Access Journals (Sweden)

    Saeedeh Hashemian

    2013-01-01

    Full Text Available In this study, oxidative discoloration of methyl violet (MV dye in aqueous solution has been studied using Fenton (Fe2+/H2O2 process. The parameters such as concentration of Fe2+, H2O2, MV, temperature, and Cl− and ions that affected of discoloration in Fenton process were investigated. The rate of degradation is dependent on initial concentration of Fe2+ ion, initial concentration of H2O2, and pH of media. Discoloration of MV was increased by increasing the temperature of reaction. Optimized condition was determined and it was found that the obtained efficiency was about 95.5% after 15 minutes of reaction at pH 3. TOC of dye sample, before and after the oxidation process, was determined. TOC removal indicates partial and significant mineralization of MV dye. The results of experiments showed that degradation of MV dye in Fenton oxidation can be described with a pseudo-irst-order kinetic model. The thermodynamic constants of the Fenton oxidation process were evaluated. The results implied that the oxidation process was feasible, spontaneous, and endothermic.

  9. Sun Ultra 5

    CERN Multimedia

    1998-01-01

    The Sun Ultra 5 is a 64-bit personal computer based on the UltraSPARC microprocessor line at a low price. The Ultra 5 has been declined in several variants: thus, some models have a processor with less cache memory to further decrease the price of the computer.

  10. H-bond network around retinal regulates the evolution of ultraviolet and violet vision

    Science.gov (United States)

    Altun, Ahmet; Morokuma, Keiji; Yokoyama, Shozo

    2011-01-01

    Ancestors of vertebrates used ultraviolet vision. Some descendants preserved ultraviolet vision while some others replaced it with violet vision, and then, some of avian lineages reinvented ultraviolet vision. Ultraviolet (absorption at ~360 nm) and violet (410–440 nm) sensitivities of visual pigments are known to be affected by around 20 amino acid substitutions. The present quantum mechanical/molecular mechanical calculations show that these substitutions modify a H-bond network formed by two waters and sites 86, 90, 113, 114, 118 and 295, which determines the protonation state of Schiff base-linked 11-cis-retinal. A pigment is ultraviolet-sensitive when it is more stable with an unprotonated retinal (SBR) form than with its protonated analog (PSBR), and is violet-sensitive when the PSBR form is more stable. These results establish for the first time the chemical basis of ultraviolet and violet vision in vertebrates. PMID:21650174

  11. Photo Inactivation of Streptococcus mutans Biofilm by Violet-Blue light.

    Science.gov (United States)

    Gomez, Grace F; Huang, Ruijie; MacPherson, Meoghan; Ferreira Zandona, Andrea G; Gregory, Richard L

    2016-09-01

    Among various preventive approaches, non-invasive phototherapy/photodynamic therapy is one of the methods used to control oral biofilm. Studies indicate that light at specific wavelengths has a potent antibacterial effect. The objective of this study was to determine the effectiveness of violet-blue light at 380-440 nm to inhibit biofilm formation of Streptococcus mutans or kill S. mutans. S. mutans UA159 biofilm cells were grown for 12-16 h in 96-well flat-bottom microtiter plates using tryptic soy broth (TSB) or TSB with 1 % sucrose (TSBS). Biofilm was irradiated with violet-blue light for 5 min. After exposure, plates were re-incubated at 37 °C for either 2 or 6 h to allow the bacteria to recover. A crystal violet biofilm assay was used to determine relative densities of the biofilm cells grown in TSB, but not in TSBS, exposed to violet-blue light. The results indicated a statistically significant (P < 0.05) decrease compared to the non-treated groups after the 2 or 6 h recovery period. Growth rates of planktonic and biofilm cells indicated a significant reduction in the growth rate of the violet-blue light-treated groups grown in TSB and TSBS. Biofilm viability assays confirmed a statistically significant difference between violet-blue light-treated and non-treated groups in TSB and TSBS. Visible violet-blue light of the electromagnetic spectrum has the ability to inhibit S. mutans growth and reduce the formation of S. mutans biofilm. This in vitro study demonstrated that violet-blue light has the capacity to inhibit S. mutans biofilm formation. Potential clinical applications of light therapy in the future remain bright in preventing the development and progression of dental caries.

  12. Ultraviolet pigments in birds evolved from violet pigments by a single amino acid change

    OpenAIRE

    Yokoyama, Shozo; Radlwimmer, F. Bernhard; Blow, Nathan S.

    2000-01-01

    UV vision has profound effects on the evolution of organisms by affecting such behaviors as mating preference and foraging strategies. Despite its importance, the molecular basis of UV vision is not known. Here, we have transformed the zebra finch UV pigment into a violet pigment by incorporating one amino acid change, C84S. By incorporating the reverse mutations, we have also constructed UV pigments from the orthologous violet pigments of the pigeon and chicken. These results and comparative...

  13. A Micro Blue-violet Laser by Frequency Doubling of Semiconductor Laser

    Institute of Scientific and Technical Information of China (English)

    周寿桓; 姜东升; 赵鸿

    2001-01-01

    In this paper, a micro blue-violet laser by frequency doubling of a semiconductor laser with a new nonlinear organometallic complex cadmium mercury thiocyanate crystal (CMTC) is reported. At room temperature, the blue-violet laser output of 11.8 mW at 404 nm and the conversion4efficiency of the second harmonic generation (SHG) of 0. 60% were obtained with a 1. 98 W, 808 nm semiconductor laser and a 4 mm crystal.

  14. 应用超量扩张形成的超薄皮瓣修复面颈部及四肢关节瘢痕组织%Application of ultra-thin expanded flap for repairing scar of neck and face and joint of extremities

    Institute of Scientific and Technical Information of China (English)

    陈骥扬; 何海填; 孟晖; 孙东原; 向明

    2016-01-01

    目的:探讨应用超量扩张形成的超薄皮瓣修复面颈部及四肢关节瘢痕组织的临床价值。方法回顾性分析2012年1月至2014年12月深圳市蛇口人民医院收治的42例面颈部及四肢关节瘢痕患者的临床资料,共置入112枚皮肤软组织扩张器,进行超过额定容积的超量扩张,形成超薄皮瓣后修复瘢痕组织。观察扩张器外露及皮瓣存活情况,评估总体修复效果,调查患者满意度。结果面颈部及四肢超薄皮瓣厚度为2.0~3.0 mm。扩张器注水期5处扩张器外露,余皆正常。皮瓣转移术后112处扩张皮瓣中10处出现皮瓣远端血运障碍,经处理后3处恢复正常、7处皮瓣坏死,但未严重影响最终治疗效果;余皮瓣成活良好。随访3~6个月,平均随访时间5个月。术后外观功能均获得明显改善,患者总体满意度90%(38/42)。结论超量扩张形成的超薄皮瓣修复面颈部及四肢关节瘢痕组织效果满意。%Objective To explore the applicable value of ultra-thin expanded flap for repairing scar of neck, face or joint of extremities. Methods Clinical data of 42 patients who were treated by ultra-thin exceedingly expanded flaps (by 112 implanted expanders of skin soft tissue) to repair scar of neck and face, joint of extremities in Shekou People's Hospital from January 2012 to December 2014, were analyzed retrospectively. The expander exposure and flap survival were observed, total repair effects were evaluated, and the patient satisfaction degree was investigated. Results The thickness of ultra-thin expanded flap was 2.0 to 3.0 mm. Five expanders were exposed during water-injection period. Of 112 expanded flaps, there were 10 flaps with distal blood circulatory disorders after skin flap transferring, in which 3 flaps survived after treatment, other 7 flaps developed necrosis without serious effects on therapeutic results. The remaining flaps survived well. The follow-up time was

  15. Tunable light source with GaN-based violet laser diode

    Science.gov (United States)

    Omori, Masaki; Mori, Naoki; Dejima, Norihiro

    2013-03-01

    GaN based violet Laser Diode has been applying for the industrial market with unique high potential characters. It has possibility Replacing Gas lasers, Dye Lasers, SHG lasers and Solid-state Lasers and more. Diode based laser extreme small and low costs at the high volume range. In addition GaN Laser has high quality with long lifetime and has possibility to cover the wide wavelength range as between 375 to 520nm. However, in general, diode based laser could only lase with Longitudinal Multi Mode. Therefore applicable application field should be limited and it was difficult to apply for the analysis. Recently, Single Longitudinal Mode laser with GaN diode has also be accomplished with external cavity by Nichia Corporation. External cavity laser achieved at least much higher than 20dB SMSR. The feature of installing laser is that Laser on the front facet with AR coating to avoid chip mode lasing. In general, external cavity laser has been required precision of mechanical assembly and Retention Capability. Nichia has gotten rid of the issue with Intelligence Cavity and YAG Laser welding assembly technique. This laser has also been installed unique feature that the longitudinal mode could be maintained to Single Mode lasing with installing internal functional sensors in the tunable laser.*1,*2 This tunable laser source could lock a particular wavelength optionally between 390 to 465nm wavelength range. As the results, researcher will have benefit own study and it will be generated new market with the laser in the near future.

  16. Extreme cosmos

    CERN Document Server

    Gaensler, Bryan

    2011-01-01

    The universe is all about extremes. Space has a temperature 270°C below freezing. Stars die in catastrophic supernova explosions a billion times brighter than the Sun. A black hole can generate 10 million trillion volts of electricity. And hypergiants are stars 2 billion kilometres across, larger than the orbit of Jupiter. Extreme Cosmos provides a stunning new view of the way the Universe works, seen through the lens of extremes: the fastest, hottest, heaviest, brightest, oldest, densest and even the loudest. This is an astronomy book that not only offers amazing facts and figures but also re

  17. Culture of the green microalga Botryococcus braunii Showa with LED irradiation eliminating violet light enhances hydrocarbon production and recovery.

    Science.gov (United States)

    Atobe, Sueko; Saga, Kiyotaka; Maeyama, Haruko; Fujiwara, Kazuhiro; Okada, Shigeru; Imou, Kenji

    2014-01-01

    The green microalga Botryococcus braunii (B. braunii), race B, was cultured under light-emitting diode (LED) irradiation with and without violet light. This study examined the effect of violet light on hydrocarbon recovery and production in B. braunii. C34 botryococcene hydrocarbons were efficiently extracted by thermal pretreatments at lower temperatures when the alga was cultured without violet light. The hydrocarbon content was also higher (approximately 3%) in samples cultured without violet light. To elucidate the mechanism of effective hydrocarbon recovery and production, we examined structural components of the extracellular matrix (ECM). The amounts of extracellular carotenoids and water-soluble polymers extracted by thermal pretreatment from the ECM were decreased when the alga was cultured without violet light. These results indicate that LED irradiation without violet light is more effective for hydrocarbon recovery and production in B. braunii. Furthermore, structural ECM components are closely involved in hydrocarbon recovery and production in B. braunii.

  18. Design and simulation of blue/violet sensitive photodetectors in silicon-on-insulator

    Institute of Scientific and Technical Information of China (English)

    Han Zhitao; Chu Jinkui; Meng Fantao; Jin Rencheng

    2009-01-01

    According to Lambert's law, a novel structure of photodetectors, namely photodetectors in silicon on-insulator, is proposed. By choosing a certain thickness value for the SOI layer, the photodetector can absorb blue/violet light effectively and affect the responsivity of the long wavelength in the visible and near-infrared re gion, making a blue/violet filter unnecessary. The material of the SOI layer is high-resistivity floating-zone silicon which can cause the neutral N type SOI layer to become fully depleted after doping with a P type impurity. This can improve the collection efficiency of short-wavelength photogenerated carriers. The device structure was optimized through numerical simulation, and the results show that the photodiode is a kind of high performance photodetector in the blue/violet region.

  19. Solvatochromic effect and kinetics of methyl violet reduction with potassium iodide in water-isopropanol mixtures

    Science.gov (United States)

    Ashfaq, Maria; Saeed, Rehana; Khan, Sameera Razi; Masood, Summyia

    2016-12-01

    The solvent influence on the reduction kinetics of methyl violet with iodide in binary mixture of aqueous isopropanol was investigated spectrophotometrically. The absorption spectra of methyl violet were recorded in water, aqueous isopropanol and absolute isopropanol. In these solvents λmax was in the range from 580.5 to 582.5 nm. The CNIBS/R-K model was used to calculate the solvatochromic parameters in a binary mixture; polynomial equation was also applied to describe the experimental data. The transition energies ( E T) were calculated. They show bathochromic shift with the decrease in the polarity of the solvent. The temperature was varied from 298-318 K, while the pH of the reaction was maintained at 4.99 and 6.00. The reduction reaction was found to be first order by potassium iodide and zero order by methyl violet. The thermodynamic parameters were also evaluated to support the kinetic data.

  20. Oxidation kinetics of crystal violet by potassium permanganate in acidic medium

    Science.gov (United States)

    Khan, Sameera Razi; Ashfaq, Maria; Mubashir; Masood, Summyia

    2016-05-01

    The oxidation kinetics of crystal violet (a triphenylmethane dye) by potassium permanganate was focused in an acidic medium by the spectrophotometric method at 584 nm. The oxidation reaction of crystal violet by potassium permanganate is carried out in an acidic medium at different temperatures ranging within 298-318 K. The kinetic study was carried out to investigate the effect of the concentration, ionic strength and temperature. The reaction followed first order kinetics with respect to potassium permanganate and crystal violet and the overall rate of the reaction was found to be second order. Thermodynamic activation parameters like the activation energy ( E a), enthalpy change (Δ H*), free energy change (Δ G*), and entropy change (Δ S*) have also been evaluated.

  1. Electrochemical Decolorization of Reactive Violet 5 Textile Dye using Pt/Ir Electrodes

    Directory of Open Access Journals (Sweden)

    Bahadır K. Körbahti

    2016-08-01

    Full Text Available Electrochemical decolorization of textile dyeing wastewater containing Reactive Violet 5 (RV5 were investigated at Pt/Ir electrodes in the presence of 75%NaCl+25%Na2CO3 (w/w supporting electrolyte mixture in a batch electrochemical reactor. Experimental parameters were operated in the range of 300-1500 mg/L textile dye concentration, 4-20 g/L 75%NaCl+25%Na2CO3 electrolyte concentration, 5-15 mA/cm2 current density, and 20-60°C reaction temperature in 15 min electrolysis time. Reactive Violet 5 decolorization increased with increasing current density and electrolyte concentration, and decreasing the textile dye concentration. Although a slight increase obtained in color removal efficiency, the temperature was not show much significant effect on decolorization. Depending on electrochemical reaction conditions, Reactive Violet 5 textile dye decolorization were obtained between 42.8-100%.

  2. 极低频高压脉冲电场对萌发玉米种子超弱发光的影响%Effect of Extremely Low Frequency High-voltage Pulsed Electric Field on Ultra-weak Luminescence of Corns during Germination

    Institute of Scientific and Technical Information of China (English)

    习岗; 刘锴; 杨运经; 高宇

    2013-01-01

    生物超弱发光是来自细胞的电磁信号,在揭示电磁生物学效应的机理研究中具有重要作用.为了研究极低频脉冲电场生物学效应及其机理,采用基于玉米细胞电位波动频率的1 Hz极低频高压脉冲电场处理萌发玉米种子,结果发现玉米种子的萌发过程明显加快,根长和芽长均有显著增长.对萌发种子的自发发光和延迟发光的测量结果显示,1 Hz极低频高压脉冲电场对萌发过程中玉米种子的自发发光和延迟发光积分强度都有明显的促进作用,表明1 Hz极低频高压脉冲电场加速了玉米种子萌发过程中的DNA合成和细胞代谢.%Biological ultra-weak luminescence is an electromagnetic signal from cells,which plays an important role in revealing the mechanism of electromagnetic biological effects.In order to study the biological effects and mechanism of extremely low frequency pulsed electric field,1 Hz extremely low frequency high-voltage pulsed electric field based on the potential fluctuation frequency of corn cells was used to treat the corns during germination.The results showed that the germination process of corns was accelerated obviously and both the shoot length and root length of germinating corns were significantly longer than the control.Through the measurement and analysis of spontaneous luminescence and delayed luminescence on corns during germination,it was found that the spontaneous luminescence and delayed luminescence integral intensity of germinating corn were significantly increased under the action of 1 Hz extremely low frequency high-voltage pulsed electric field,which indicated that this specific pulsed electric field promoted the DNA synthesis and cell metabolism of the corns during germination.The coupled resonance of pulsed electric field and cell electric field in corn seeds may be the cause of biological effects of the extremely low frequency high-voltage pulsed electric field.

  3. Kinetics of polarization gratings assisted with polarized violet light in bacteriorhodopsin films.

    Science.gov (United States)

    Yu, Xianghua; Gao, Peng; Yao, Baoli; Lei, Ming; Rupp, Romano

    2013-09-01

    Polarization gratings can be recorded in bacteriorhodopsin films by an orthogonal pair of linearly or circularly polarized beams. If a linearly polarized auxiliary violet light is added during the grating formation, the grating becomes polarization-sensitive. A theoretical model based on the two-state photochromic theory is proposed to calculate the diffraction efficiency kinetics of these polarization gratings. In both cases, the additional linearly polarized auxiliary violet irradiation improves the steady-state diffraction efficiency and leads to a cosine modulation of the steady-state diffraction efficiency by the polarization orientation of the readout beam. Experiment results demonstrate the correctness of the theoretical model.

  4. Ultraviolet pigments in birds evolved from violet pigments by a single amino acid change

    Science.gov (United States)

    Yokoyama, Shozo; Radlwimmer, F. Bernhard; Blow, Nathan S.

    2000-01-01

    UV vision has profound effects on the evolution of organisms by affecting such behaviors as mating preference and foraging strategies. Despite its importance, the molecular basis of UV vision is not known. Here, we have transformed the zebra finch UV pigment into a violet pigment by incorporating one amino acid change, C84S. By incorporating the reverse mutations, we have also constructed UV pigments from the orthologous violet pigments of the pigeon and chicken. These results and comparative amino acid sequence analyses of the pigments in vertebrates demonstrate that many avian species have achieved their UV vision by S84C. PMID:10861005

  5. [Effects of two trypanosomicide drugs, gention violet and WR6026, on platelet concentrates preservation].

    Science.gov (United States)

    Soares, Sheila; Moraes-Souza, Hélio; Tostes, Maria Aparecida Vieira; Lourenço, Dayse Maria

    2004-01-01

    In order to verify the viability of platelet concentrate during its preservation period when added with two trypanosomicidal chemical substances, gentian violet and quinoline WR6026, we tested these concentrates and verified the following parameters: number of platelets, pH and platelet aggregation test with a pair of agonists. Significant alterations were observed in the platelet concentrate treated with gentian violet suggesting important damage to the platelet viability. With WR6026 similar values to the controls were observed, opening new perspectives for the utilization of this salt for the chemoprophylaxis of transfusional Chagas' disease in highly endemic regions.

  6. "In vitro" activity of gentian violet against asexual Plasmodium falciparum parasites

    Directory of Open Access Journals (Sweden)

    Shen Lin Yang

    1988-02-01

    Full Text Available In order to investigate whether gentian violet exhibited "in vitro" inhibitory activity against Plasmodium falciparum, the Authors have carried out 20 sensitivity tests according to the microtechnique described by RIECK MANN et al.5. Results have shown inhibition of schizonts'maturation at the following concentration: 1/1000; 1/1500; 1/2000; 1/2500; 1/3000 and 1/4000, thus demonstrating inhibitory activity of the tested dye against asexual blood parasites. The present data suggest gentain violet may be possibly used in the prophylaxis of transfusion-acquired malaria.

  7. Interactions between crystal violet and AOT in aqueous solutions and in AOT/isooctane/water microemulsions

    Institute of Scientific and Technical Information of China (English)

    HAO Xiaojuan; AN Xueqin; CHEN Zhiyun; SHEN Weiguo

    2004-01-01

    The absorbance of crystal violet (CV) in a series of aqueous solutions and a series of sodium bis(2-ethyl- hexyl) sulfosuccinate (AOT)/isooctane/water microemulsions has been determined. Association models have been used to analyse the experimental data to obtain the association constants of CV and AOT in the above two media. It was found that about up to 57% CV was associated by AOT in AOT/ isooctane/water microemulsions, which reduced the reaction rate of alkaline fading of crystal violet in the microemulsions.

  8. Advanced Ultra-Violet (UV) Aircraft Fire Detection System. Volume 3. Ground Support Equipment (GSE) for System Check-Out

    Science.gov (United States)

    1982-08-01

    Springer, Program Manager, directed the efforts of P.H. Lang , W.B. Kirk, B.B. Witte, D.C. Nelson, and J. Phillips. The overall effort was under the...50-078 7.. .. . .Erie. 333 Jumpers. plug-in ... . .-........ .....51.18194 Serg . 65474-002 J3 .... . Printhead connector

  9. Molecular beam epitaxy-grown wurtzite MgS thin films for solar-blind ultra-violet detection

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Y. H.; He, Q. L. [Nano Science and Nano Technology Program, The Hong Kong University of Science and Technology, HKSAR, People' s Republic of China (China); Department of Physics and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, HKSAR, People' s Republic of China (China); Cheung, W. Y.; Lok, S. K.; Wong, K. S.; Sou, I. K. [Department of Physics and William Mong Institute of Nano Science and Technology, The Hong Kong University of Science and Technology, HKSAR, People' s Republic of China (China); Ho, S. K. [Faculty of Science and Technology, University of Macau, Macau, People' s Republic of China (China); Tam, K. W. [Department of Electrical and Electronics Engineering, University of Macau, Macau, People' s Republic of China (China)

    2013-04-29

    Molecular beam epitaxy grown MgS on GaAs(111)B substrate was resulted in wurtzite phase, as demonstrated by detailed structural characterizations. Phenomenological arguments were used to account for why wurtzite phase is preferred over zincblende phase or its most stable rocksalt phase. Results of photoresponse and reflectance measurements performed on wurtzite MgS photodiodes suggest a direct bandgap at around 5.1 eV. Their response peaks at 245 nm with quantum efficiency of 9.9% and enjoys rejection of more than three orders at 320 nm and close to five orders at longer wavelengths, proving the photodiodes highly competitive in solar-blind ultraviolet detection.

  10. LADEE UVS (UltraViolet Visible Spectrometer) and the Search for Lunar Exospheric Dust: A Detailed Spectral Analysis

    Science.gov (United States)

    Wooden, Diane H.; Cook, Amanda; Colaprete, Anthony; Shirley, Mark; Vargo, Kara; Elphic, Richard C.; Hermalyn, Brendan; Stubbs, Timothy John; Glenar, David A.

    2014-01-01

    The Lunar Atmosphere and Dust Environment Explorer (LADEE) executed science observations in lunar orbit spanning 2013-Oct-16- 2014-04-18 UT. LADEE's Ultraviolet/Visible Spectrometer (UVS) studies the composition and temporal variations of the tenuous lunar exosphere and dust environment, utilizing two sets of optics: a limb-viewing telescope, and a solar-viewer. The limb-viewing telescope observes illuminated dust and emitting gas species while the Sun is just behind the lunar limb. The solar viewer, with its diffuser, allows UVS to also stare directly at the solar disk as it approaches the limb, sampling progressively lower exosphere altitudes. Solar viewer "Occultation" activities occur at the lunar sunrise limb, as the LADEE spacecraft passes into the lunar night side, facing the Sun (the spacecraft orbit is near-equatorial retrograde). A loss of transmission of sunlight occurs by the occultation of dust grains along the line-of-sight. So-called "Inertial Limb" activities have the limb-viewing telescope pointed at the lit exosphere just after the Sun has set. Inertial Limb activities follow a similar progression of diminishing sampling altitudes but hold the solar elongation angle constant so the zodiacal light contribution remains constant while seeking to observe the weak lunar horizon glow. On the dark side of the moon, "Sodium Tail" activities pointed the limb-viewing telescope in the direction of the Moon's sodium tail (similar to anti-sunward), during different lunar phases. Of the UVS data sets, these show the largest excess of scattered blue light, indicative of the presence of small (approximately 100 nm) dust grains in the tail. Correlations are sought between dust in the sodium tail and meteor streams and magnetotail crossings to investigate impact- versus electrostatic-lofting. Once lofted, nanoparticles can become charged and picked up by the solar wind. The LADEE UVS Occultation, Inertial Limb, and Sodium Tail spectral datasets provide evidence of a lunar dust exosphere.

  11. Ultra violet sensors based on nanostructured ZnO spheres in network of nanowires: a novel approach

    Directory of Open Access Journals (Sweden)

    Luykx A

    2007-01-01

    Full Text Available AbstractThe ZnO nanostructures consisting of micro spheres in a network of nano wires were synthesized by direct vapor phase method. X-ray Photoelectron Spectroscopy measurements were carried out to understand the chemical nature of the sample. ZnO nanostructures exhibited band edge luminescence at 383 nm. The nanostructure based ZnO thin films were used to fabricate UV sensors. The photoresponse measurements were carried out and the responsivity was measured to be 50 mA W−1. The rise and decay time measurements were also measured.

  12. Effects of environmental aging and ultra violet radiation on asphalt mixture dynamic modulus, permanent deformation and fatigue life

    Directory of Open Access Journals (Sweden)

    Wilmar Darío Fernández-Gómez

    2016-01-01

    Full Text Available El envejecimiento produce cambios en las propiedades de las mezclas asfálticas como debilitar la adhesión asfalto - agregado y el incremento de la rigidez y la viscosidad del asfalto. Adicionalmente, esos cambios afectan la durabilidad del pavimento asfáltico. El objetivo de este estudio es evaluar el comportamiento de las mezclas asfálticas bajo diferentes condiciones de envejecimiento comparando muestras sometidas a envejecimiento en cámara de radiación UV y otras extraídas de vías en terreno. Las mezclas de laboratorio se fabricaron con material granular de una fuente y un cemento asfaltico. Cuatro grupos de mezclas se analizaron: No envejecidas, envejecidas en laboratorio mediante UV y Vaso de envejecimiento presión y envejecidas en campo. Para el tratamiento de envejecimiento por radiación ultravioleta, se diseñó una cámara y las muestras se trataron en periodos de 100, 200 y 500 horas. Se extrajeron muestras de pavimentos en servicio de edades entre 1,5 y 11 años después de la construcción. El comportamiento mecánico se evaluó mediante ensayos de modulo dinámico, deformación permanente y fatiga trapezoidal. Lo resultados mostraron que el envejecimiento incrementa la rigidez del material hasta dos veces con respecto al material sin envejecer. La deformación permanente muestra un mejor desempeño en las muestras envejecidas que en aquella sin exposición al envejecimiento. Por otro lado, el envejecimiento afecta de manera negativa la vida de fatiga dado que se presentan

  13. The effect of heat- or ultra violet ozone-treatment of titanium on complement deposition from human blood plasma.

    Science.gov (United States)

    Linderbäck, Paula; Harmankaya, Necati; Askendal, Agneta; Areva, Sami; Lausmaa, Jukka; Tengvall, Pentti

    2010-06-01

    Titanium (Ti) is a well known metallic biomaterial extensively used in dental, orthopaedic-, and occasionally also in blood contacting applications. It integrates well to bone and soft tissues, and is shown upon blood plasma contact to activate the intrinsic pathway of coagulation and bind complement factor 3b. The material properties depend largely on those of the nm-thick dense layer of TiO(2) that becomes rapidly formed upon contact with air and water. The spontaneously formed amorphous Ti-oxide has a pzc approximately 5-6 and its water solubility is at the order of 1-2 micromolar. It is often subjected to chemical- and heat treatments in order to increase the anatase- and rutile crystallinity, to modify the surface topography and to decrease the water solubility. In this work, we prepared sol-gel derived titanium and smooth PVD titanium surfaces, and analysed their oxide and protein deposition properties in human blood plasma before and after annealing at 100-500 degrees C or upon UVO-treatment for up to 96 hours. The blood plasma results show that complement deposition vanished irreversibly after heat treatment at 250-300 degrees C for 30 minutes or after UVO exposure for 24 hours or longer. XPS and infrared spectroscopy indicated change of surface water/hydroxyl binding upon the heat- and UVO treatments, and increased Ti oxidation. XRD analysis confirmed an increased crystallinity and both control (untreated) and annealed smooth titanium displayed low XRD-signals indicating some nanocrystallinity, with predominantly anatase phase. The current results show that the behaviour of titanium dioxide in blood contact can be controlled through relatively simple means, such as mild heating and illumination in UV-light, which both likely irreversibly change the stoichiometry and structure of the outmost layers of titanium dioxide and its OH/H(2)O binding characteristics.

  14. Ultra-violet B (UVB)-induced skin cell death occurs through a cyclophilin D intrinsic signaling pathway

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Chao [Department of Dermatology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu (China); Yang, Bo [Department of Dermatology, Huashan Hospital, Fudan University, Shanghai 200040 (China); Yang, Zhi; Tu, Ying [Department of Dermatology, The First Affiliated Hospital of Kunming Medical University, Yunnan Provincial Institute of Dermatology, Kunming 650032, Yunnan (China); Yang, Yan-li [Department of Otorhinolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu (China); He, Li, E-mail: heli2662@yahoo.com.cn [Department of Otorhinolaryngology, The First Affiliated Hospital of Nanjing Medical University, Nanjing 210024, Jiangsu (China); Bi, Zhi-Gang, E-mail: eltonbibenqhospital@yahoo.com.cn [Department of Dermatology, BenQ Medical Center, Nanjing Medical University, Nanjing 210019, Jiangsu (China)

    2012-09-07

    Highlights: Black-Right-Pointing-Pointer UVB radiated skin keratinocytes show cyclophilin D (Cyp-D) upregulation. Black-Right-Pointing-Pointer NAC inhibits UVB induced Cyp-D expression, while H{sub 2}O{sub 2} facilitates it. Black-Right-Pointing-Pointer Cyp-D-deficient cells are significantly less susceptible to UVB induced cell death. Black-Right-Pointing-Pointer Over-expression of Cyp-D causes spontaneous keratinocytes cell death. -- Abstract: UVB-induced skin cell damage involves the opening of mitochondrial permeability transition pore (mPTP), which leads to both apoptotic and necrotic cell death. Cyclophilin D (Cyp-D) translocation to the inner membrane of mitochondrion acts as a key component to open the mPTP. Our Western-Blot results in primary cultured human skin keratinocytes and in HaCaT cell line demonstrated that UVB radiation and hydrogen peroxide (H{sub 2}O{sub 2}) induced Cyp-D expression, which was inhibited by anti-oxidant N-acetyl cysteine (NAC). We created a stable Cyp-D deficiency skin keratinocytes by expressing Cyp-D-shRNA through lentiviral infection. Cyp-D-deficient cells were significantly less susceptible than their counterparts to UVB- or H{sub 2}O{sub 2}-induced cell death. Further, cyclosporine A (Cs-A), a Cyp-D inhibitor, inhibited UVB- or H{sub 2}O{sub 2}-induced keratinocytes cell death. Reversely, over-expression of Cyp-D in primary keratinocytes caused spontaneous keratinocytes cell death. These results suggest Cyp-D's critical role in UVB/oxidative stress-induced skin cell death.

  15. The role of graphene formed on silver nanowire transparent conductive electrode in ultra-violet light emitting diodes

    Science.gov (United States)

    Seo, Tae Hoon; Lee, Seula; Min, Kyung Hyun; Chandramohan, S.; Park, Ah Hyun; Lee, Gun Hee; Park, Min; Suh, Eun-Kyung; Kim, Myung Jong

    2016-07-01

    This paper reports a highly reliable transparent conductive electrode (TCE) that integrates silver nanowires (AgNWs) and high-quality graphene as a protecting layer. Graphene with minimized defects and large graphene domains has been successfully obtained through a facile two-step growth approach. Ultraviolet light emitting diodes (UV-LEDs) were fabricated with AgNWs or hybrid electrodes where AgNWs were combined with two-step grown graphene (A-2GE) or conventional one-step grown graphene (A-1GE). The device performance and reliability of the UV-LEDs with three different electrodes were compared. The A-2GE offered high figure of merit owing to the excellent UV transmittance and reduced sheet resistance. As a consequence, the UV-LEDs made with A-2GE demonstrated reduced forward voltage, enhanced electroluminescence (EL) intensity, and alleviated efficiency droop. The effects of joule heating and UV light illumination on the electrode stability were also studied. The present findings prove superior performance of the A-2GE under high current injection and continuous operation of UV LED, compared to other electrodes. From our observation, the A-2GE would be a reliable TCE for high power UV-LEDs.

  16. Rest-frame ultra-violet spectra of massive galaxies at z=3: evidence for high-velocity outflows

    CERN Document Server

    Karman, W; Trager, S C; Almaini, O; Cirasuolo, M

    2013-01-01

    Galaxy formation models invoke the presence of strong feedback mechanisms that regulate the growth of massive galaxies at high redshifts. In this paper we aim to: (1) confirm spectroscopically the redshifts of a sample of massive galaxies selected with photometric redshifts larger than 2.5; (2) investigate the properties of their stellar and interstellar media; (3) detect the presence of outflows, and measure their velocities. To achieve this, we analysed deep, high-resolution (R=2000) FORS2 rest-frame UV spectra for 11 targets. We confirmed that 9 out of 11 have spectroscopic redshifts larger than 2.5. We also serendipitously found two mask fillers at redshift larger than 2.5, which originally were assigned photometric redshifts between 2.0 and 2.5. In the four highest-quality spectra we derived outflow velocities by fitting the absorption line profiles with models including multiple dynamical components. We found strongly asymmetric, high-ionisation lines, from which we derived outflow velocities ranging be...

  17. Fast carbohydrate analysis via liquid chromatography coupled with ultra violet and electrospray ionization ion trap detection in 96-well format.

    Science.gov (United States)

    Rühmann, Broder; Schmid, Jochen; Sieber, Volker

    2014-07-11

    A fast carbohydrate screening platform processible in 96-well format is described. The method is suitable for the determination of various carbohydrates out of complex mixtures as obtained by acidic hydrolysis of carbohydrates polymers. The chromatographic conditions for an efficient separation (12min) and the derivatization process with 1-phenyl-3-methyl-5-pyrazolone (PMP) were optimized for high resolution separation and simultaneous determination of deoxy-, amino-, anhydro-sugars as well as hexoses, pentoses, dimers, uronic acids and degradation products like furfural and hydroxymethylfurfural (HMF). The potential to quantify with UV- and MS-detector in the same range has been demonstrated for 20 different compounds. Finally, the matrix effects of the hydrolysis were positively evaluated. The micro scale hydrolysis and PMP-derivatization without any extraction or drying steps, both in 96-well format, result in a fast and intuitive sample preparation. In combination with a fast liquid chromatography coupled to UV and electrospray ionization ion trap detection (LC-UV-ESI-MS/MS) for the qualification and quantification of various sugars, dimers and degradation products, this method shows great performance in carbohydrate analysis.

  18. The Type IIP SN 2005ay: An Extensive Study From UltraViolet To Near-IR

    Science.gov (United States)

    Bufano, F. M.; Turatto, M.; Zampieri, L.; Gal-Yam, A.

    2006-08-01

    Several supernova types are thought to explode via the gravitational collapse of the core of massive stars at the end of their lifetimes. The great observational diversity has not been fully understood even if it clearly involves the progenitor masses and configurations at the time of explosion. These Supernovae, called Core Collapse Supernovae (CC SNe), are expected to dominate the counts of SNe observed at high redshifts and to be the only observable probe of the first generation stars (Pop III). Recently indicated as reliable distance indicators (Hamuy 02, Pastorello `03), CC SNe are objects of great interest but significantly less studied in comparison with the Termonuclear ones. With the aim to understand better the reasons of the heterogeneous behaviour , we have started an extensive study of the properties of SN II with different observational features (luminosity, velocity, etc..). Here we present the last results on our first observed target, SN2005ay, a Type IIP supernova observed in an extended way from the Ultraviolet wavelengths, provided by the GALEX , to the Optical and near-IR , obtained with IISP (Italian Intensive Supernova Program).

  19. A Study of Ultra-Violet Irradiation on Epithelial Tissue of Fresh Water Fish, “Puntius Sophore”

    Directory of Open Access Journals (Sweden)

    Vivek Sharma

    2016-09-01

    Full Text Available The small indigenous fishes (SIFs are known to be micronutrient rich. The gene Puntius comprises of about 134 beautiful species, out of which PuntiusSophore is an important species. Comprehensive nutrient profile of PuntiusSophore showed that it is rich in protein and minerals. In the present study we are investigating the effect of UV irradiation on epithelial tissue of fish, PuntiusSophore. The quantities of various mineral constituents, fat and amino acids were analyzed at different time intervals. This study was undertaken to evaluate the mineral and organic chemical constituents present in scale of fish, PuntiusSophore. The minerals (Na, Ca, Mg, P, and F, CO2 and organic constituents (fat, protein and nitrogen were determined before and after the time intervals of 1 hour, 10 hours and 20 hours of U.V. irradiation. All mineral constituents remain unchanged after U.V. irradiation. Total nitrogen, crude fat and crude protein showed continuous decrease with increase in the time of exposure. Percentage decrease in total nitrogen, crude fat and crude protein after 20 hour exposure was 2.784, 7.79 and 2.88 respectively. Likewise Amino acids content in fish scale decreases, maximum being in case of valine after 20 hours exposure. The reason for this decrease is the C-C bond cleavage with the formation of free radicals and evolution of ammonia. Exposure also reduced the weight of the scale powder.

  20. Cisplatin and ultra-violet-C synergistically down-regulate receptor tyrosine kinases in human colorectal cancer cells

    Directory of Open Access Journals (Sweden)

    Kawaguchi Junji

    2012-07-01

    Full Text Available Abstract Background Platinum-containing anti-cancer drugs such as cisplatin are widely used for patients with various types of cancers, however, resistance to cisplatin is observed in some cases. Whereas we have recently reported that high dose UV-C (200 J/m² induces colorectal cancer cell proliferation by desensitization of EGFR, which leads oncogenic signaling in these cells, in this study we investigated the combination effect of low dose cisplatin (10 μM and low dose UV-C (10 J/m² on cell growth and apoptosis in several human colorectal cancer cells, SW480, DLD-1, HT29 and HCT116. Results The combination inhibited cell cycle and colony formation, while either cisplatin or UV-C alone had little effect. The combination also induced apoptosis in these cells. In addition, the combination caused the downregulation of EGFR and HER2. Moreover, UV-C alone caused the transient internalization of the EGFR, but with time EGFR recycled back to the cell surface, while cisplatin did not affect its localization. Surprisingly, the combination caused persistent internalization of the EGFR, which results in the lasting downregulation of the EGFR. Conclusions The combination of low dose cisplatin and low dose UV-C synergistically exerted anti-cancer effect by down-regulating RTK, such as EGFR and HER2. These findings may provide a novel strategy for the treatment of patients with colorectal cancer.

  1. Advanced Ultra-Violet (UV) Aircraft Fire Detection System. Volume 2. System Hardware Design, Software Design, and Test

    Science.gov (United States)

    1982-08-01

    599 .SIJPROUTINE ADJSEIAUTHOR NIGEL YOUNG ( 0900 Dato .;h.et: D0~.5306 .Th..ti 27 Issue: A -13- AS 12/67/79 esee600 ..CALLED BY INITIALIZATION epee...8217 iVolta/Metr.o Vol.a,, etre, VoZ ./tue 3 Volt Rande ! 1.0 1.0 0.9 P22.0 1.99 1.9 2.5 2.5 2.44 3.0 3.0 3.0 t 10 Volt Ronge 4.o 4.0 4.0 5.0 5.0 4.9 6.o

  2. 3D textural evidence for the formation of ultra-high tenor precious metal bearing sulphide microdroplets in offset reefs: An extreme example from the Platinova Reef, Skaergaard Intrusion, Greenland

    Science.gov (United States)

    Holwell, David A.; Barnes, Stephen J.; Le Vaillant, Margaux; Keays, Reid R.; Fisher, Louise A.; Prasser, Richard

    2016-07-01

    The Platinova Reef in the Skaergaard Intrusion, east Greenland, is an example of a type of layered-intrusion-hosted, precious metal-enriched, stratiform, disseminated sulphide deposit referred to as "offset reefs". These typically show platinum-group element (PGE) enrichment immediately below a major increase in the abundance of Cu-rich sulphides, with a prominent peak in Au enrichment exactly at that transition between the PGE-rich and the Cu-sulphide-rich zones. The reasons for the relative sequence of offsets in metal peaks, and the occasionally very high metal tenors have been subject to great debate. Here we use an integrated approach of high-resolution X-ray computed tomography (HRXCT), SEM, synchrotron and desktop microbeam XRF mapping, and thin section petrography to comprehensively classify the textural relations of the precious metal-bearing sulphides of the Platinova Reef as an extreme end member example of an exceedingly high tenor offset deposit. Our results show that in the zones of PGE enrichment, precious metal minerals (PMMs) are intimately associated with Cu sulphide globules, mostly located at, or close to, silicate and oxide boundaries. The textures are identical in zones enriched in Pd and Au, and thus we do not see any evidence for different processes forming the different zones. The PMM:Cu sulphide ratio in each globule varies significantly but overall the size of the globules increases from the Pd-rich, through the Au-rich, and into the Cu zone, with a significant corresponding decrease in PM tenor. As such, this records a progression of exceedingly high tenor, microdroplets of sulphide, which progressively get larger up through the section, and decrease in tenor proportionally to their size. Cumulus droplets of Cu sulphide became enriched in metals, and were trapped in situ without significant transport from their point of nucleation. The transition to larger sulphides represents a change from sulphides nucleated and trapped in situ, to

  3. 基于样本熵和极端学习机的超短期风电功率组合预测模型%Combined Model for Ultra Short-term Wind Power Prediction Based on Sample Entropy and Extreme Learning Machine

    Institute of Scientific and Technical Information of China (English)

    张学清; 梁军; 张熙; 张峰; 张利; 徐兵

    2013-01-01

    该文提出一种经验模态分解(empirical mode 该文提出一种经验模态分解(empirical mode decomposition,EMD)-样本熵(sample entropy,SE)和极端学习机(extreme learning machine,ELM)相结合的风电功率超短期预测方法。该方法首先利用 EMD-SE 将风电功率时间序列分解为一系列复杂度差异明显的风电子序列;其次利用最小二乘支持向量机(least squares support vector machine, LSSVM)、极端学习机和经原始岭回归(primal ridge regression,PRR)改进的极端学习机(PRR-ELM)对各子序列建立组合预测模型,并采用交叉验证法和重构相空间法确定各模型的参数和输入向量维数,以提高各组合模型的预测精度;最后以某一风电场实际采集的数据为算例,结果表明基于EMD-SE理论的ELM和PRR-ELM组合预测模型在预测精度和训练速度上都明显优于 EMD-SE 理论和 LSSVM 的组合模型,且其预测结果更接近于真实值,为实现风电功率在线的较高精度超短期预测提供了可能。%An ultra short-term wind power combined prediction approach based on empirical mode decomposition (EMD)-sample entropy (SE) and extreme learning machine (ELM) was proposed. Firstly, the wind power time series was decomposed into a series of wind power subsequences with obvious differences in complex degree by using EMD-SE. Secondly, the prediction models of each subsequence were constructed with least squares support vector machine (LSSVM), extreme learning machine (ELM) and ELM improved by primal ridge regression (PRR-ELM), of which the parameters and the input vector dimensions were determined by cross validation and chaotic phase space theory to improve the forecasting accuracy of each prediction model. Finally, taking the actual collecting data of certain a wind farm for an example, the simulation results illustrate that ELM and PRR-ELM prediction model based on EMD-SE are much better than the combined LSSVM model

  4. Extremely compliant and highly stretchable patterned graphene

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Shuze; Huang, Yinjun; Li, Teng, E-mail: LiT@umd.edu [Department of Mechanical Engineering and Maryland NanoCenter, University of Maryland, College Park, Maryland 20742 (United States)

    2014-04-28

    Graphene is intrinsically ultra-stiff in its plane. Its huge mechanical mismatch when interfacing with ultra-compliant biological tissues and elastomers (7–9 orders of magnitude difference in stiffness) poses significant challenge in its application to functional devices such as epidermal electronics and sensing prosthesis. We offer a feasible and promising solution to this significant challenge by suitably patterning graphene into a nanomesh. Through systematic coarse-grained simulations, we show that graphene nanomesh can be made extremely compliant with nearly zero stiffness up to about 20% elongation and then remain highly compliant up to about 50% elongation.

  5. 75 FR 34699 - Carbazole Violet Pigment 23 from India: Rescission of Countervailing Duty Administrative Review

    Science.gov (United States)

    2010-06-18

    ... International Trade Administration Carbazole Violet Pigment 23 from India: Rescission of Countervailing Duty... 23(CVP-23) from India. See Antidumping or Countervailing Duty Order, Finding, or Suspended... countervailing duty order on CVP-23 from India for the period January 1, 2008 through December 31, 2008. In...

  6. Violet and blue light-induced green fluorescence emissions from dental caries.

    Science.gov (United States)

    Shakibaie, F; Walsh, L J

    2016-12-01

    The objective of this laboratory study was to compare violet and visible blue LED light-elicited green fluorescence emissions from enamel and dentine in healthy or carious states. Microscopic digital photography was undertaken using violet and blue LED illumination (405 nm and 455 nm wavelengths) of tooth surfaces, which were photographed through a custom-made stack of green compensating filters which removed the excitation light and allowed green fluorescence emissions to pass. Green channel pixel data were analysed. Dry sound enamel and sound root surfaces showed strong green fluorescence when excited by violet or blue lights. Regions of cavitated dental caries gave lower green fluorescence, and this was similar whether the dentine in the lesions was the same colour as normal dentine or was darkly coloured. The presence of saliva on the surface did not significantly change the green fluorescence, while the presence of blood diluted in saliva depressed green fluorescence. Using violet or blue illumination in combination with green compensating filters could potentially aid in the assessment of areas of mineral loss. © 2016 Australian Dental Association.

  7. Integumental reddish-violet coloration owing to novel dichromatic chromatophores in the teleost fish, Pseudochromis diadema.

    Science.gov (United States)

    Goda, Makoto; Ohata, Mihoko; Ikoma, Hayato; Fujiyoshi, Yoshinori; Sugimoto, Masazumi; Fujii, Ryozo

    2011-08-01

    In the reddish-violet parts of the skin of the diadema pseudochromis Pseudochromis diadema, we found novel dichromatic chromatophores with a reddish pigment and reflecting platelets. We named these novel cells 'erythro-iridophores'. In standard physiological solution, erythro-iridophores displayed two hues, red and dark violet when viewed with an optical microscope under ordinary transmission light and epi-illumination optics, respectively. Under transmission electron microscopy, however, we observed no typical red chromatosomes, i.e., erythrosomes, in the cytoplasm. High-performance thin-layer chromatography (HPTLC) analysis of the pigment eluted from the erythro-iridophores indicated that carotenoid is the main pigment generating the reddish color. Furthermore, when the irrigating medium was a K(+)-rich saline solution, the color reflected from the erythro-iridophores changed from dark violet to sky blue, but the red coloration remained. The motile activities of the erythro-iridophores may participate in the changes in the reddish-violet shades of the pseudochromis fish.

  8. Violet LED light enhances the recruitment of a thrip predator in open fields

    Science.gov (United States)

    Ogino, Takumi; Uehara, Takuya; Muraji, Masahiko; Yamaguchi, Terumi; Ichihashi, Takahisa; Suzuki, Takahiro; Kainoh, Yooichi; Shimoda, Masami

    2016-01-01

    The predatory bug Orius sauteri is an indigenous natural enemy of thrips and whiteflies in Asian countries. To put these bugs to practical use in pest management, methods to attract and retain the bugs in agricultural fields are needed. We previously showed that violet light (405 nm) attracts O. sauteri selectively. Many thrips and whiteflies are attracted to UV or green light. In this study, we examined the effect of violet-LED illumination on O. sauteri in pesticide-free eggplant (Solanum melongena L.) cultivation. In three cultivation trials, the density of O. sauteri on eggplant leaves was consistently higher in the illuminated plots; at least twice that of the non-illuminated plots. Simultaneously, the density of thrips declined markedly to less than half that of the non-illuminated plots. We identified three positive effects of violet light including an “immediate-effect” on predator attraction, a “persistent-effect” on predator reproduction, and a “secondary-effect” on the food web structure. Our results showed that illumination with violet light provides a powerful tool for integrated pest management. This is the first report on the use of illumination to manipulate the behavior of natural enemies. PMID:27604315

  9. Adaptive evolutionary paths from UV reception to sensing violet light by epistatic interactions

    Science.gov (United States)

    Yokoyama, Shozo; Altun, Ahmet; Jia, Huiyong; Yang, Hui; Koyama, Takashi; Faggionato, Davide; Liu, Yang; Starmer, William T.

    2015-01-01

    Ultraviolet (UV) reception is useful for such basic behaviors as mate choice, foraging, predator avoidance, communication, and navigation, whereas violet reception improves visual resolution and subtle contrast detection. UV and violet reception are mediated by the short wavelength–sensitive (SWS1) pigments that absorb light maximally (λmax) at ~360 nm and ~395 to 440 nm, respectively. Because of strong nonadditive (epistatic) interactions among amino acid changes in the pigments, the adaptive evolutionary mechanisms of these phenotypes are not well understood. Evolution of the violet pigment of the African clawed frog (Xenopus laevis, λmax = 423 nm) from the UV pigment in the amphibian ancestor (λmax = 359 nm) can be fully explained by eight mutations in transmembrane (TM) I–III segments. We show that epistatic interactions involving the remaining TM IV–VII segments provided evolutionary potential for the frog pigment to gradually achieve its violet-light reception by tuning its color sensitivity in small steps. Mutants in these segments also impair pigments that would cause drastic spectral shifts and thus eliminate them from viable evolutionary pathways. The overall effects of epistatic interactions involving TM IV–VII segments have disappeared at the last evolutionary step and thus are not detectable by studying present-day pigments. Therefore, characterizing the genotype-phenotype relationship during each evolutionary step is the key to uncover the true nature of epistasis. PMID:26601250

  10. Adsorption of Crystal Violet Dye Using Zeolite A Synthesized From Coal Fly Ash

    Science.gov (United States)

    Jumaeri; Kusumastuti, E.; Santosa, S. J.; Sutarno

    2017-02-01

    Adsorption of Crystal Violet (CV) dye using zeolite A synthesized from coal fly ash (ZA) has been done. Effect of pH, contact time, and the initial concentration of dye adsorption was studied in this adsorption. Model experimental of adsorption isotherms and adsorption kinetics were also studied. The adsorption is done in a batch reactor at room temperature. A total of 0.01 g of zeolite A was added to the Erlenmeyer flask 50 mL containing 20 mL of the dye solution of Crystal Violet in a variety of conditions of pH, contact time and initial concentration. Furthermore, Erlenmeyer flask and its contents were shaken using an orbital shaker at a speed of 200 rpm. After a specified period of adsorption, the solution was centrifuged for 2 minutes so that the solids separated from the solution. The concentration of the dye after adsorption determined using Genesis-20 Spectrophotometer. The results showed that the Zeolite A synthesized from coal fly ash could be used as an effective adsorbent for Crystal Violet dye. The optimum adsorption occurs at pH 6, and contact time 45 minutes. At the initial concentration of 2 to 6 mg/L, adsorption is reduced from 79 to 62.8%. Crystal Violet dye adsorption in zeolite A fulfilled kinetic model of pseudo-order 2 and model of Freundlich adsorption isotherm.

  11. Removal of methyl violet dye by adsorption onto N-benzyltriazole derivatized dextran

    DEFF Research Database (Denmark)

    Cho, Eunae; Tahir, Muhammad Nazir; Kim, Hwanhee

    2015-01-01

    In this work, N-benzyltriazole derivatized dextran was evaluated for its potential as a novel carbohydrate-based adsorbent for the removal of methyl violet dye from water. The modified dextran was synthesized by a click reaction of pentynyl dextran and benzyl azide, and the structure...

  12. Ultra-endurance exercise: unanswered questions in redox biology and immunology

    NARCIS (Netherlands)

    Turner, J.E.; Bennett, S.J.; Bosch, J.A.; Griffiths, H.S.; Aldred, S.

    2014-01-01

    Ultra-endurance races are extreme exercise events that can take place over large parts of a day, several consecutive days or over weeks and months interspersed by periods of rest and recovery. Since the first ultra-endurance races in the late 1970s, around 1000 races are now held worldwide each

  13. Side population analysis using a violet-excited cell-permeable DNA binding dye.

    Science.gov (United States)

    Telford, William G; Bradford, Jolene; Godfrey, William; Robey, Robert W; Bates, Susan E

    2007-04-01

    Hoechst 33342 side population (SP) analysis is a common method for identifying stem cells in mammalian hematopoietic and nonhematopoietic tissues. Although widely employed for stem cell analysis, this method requires an ultraviolet (UV) laser to excite Hoechst 33342. Flow cytometers equipped with UV sources are not common because of the cost of both the laser and optics that can transmit light UV light. Violet laser sources are inexpensive and are now common fixtures on flow cytometers, but have been previously shown to provide insufficient Hoechst dye excitation for consistent resolution of SP cells. One solution to this problem is to identify additional fluorescent substrates with the same pump specificity as Hoechst 33342, but with better violet excitation characteristics. DyeCycle Violet reagent has emission characteristics similar to those of Hoechst 33342, but with a longer wavelength excitation maxima (369 nm). When this dye is loaded into hematopoietic cells, a sharply resolved side population was also observed, similar in appearance to that seen with Hoechst 33342. Unlike Hoechst SP, DCV SP was similar in appearance with both violet and UV excitation. DCV SP could be inhibited fumitremorgin C, and showed the same membrane pump specificity as Hoechst 33342. Simultaneous immunophenotyping with stem cell markers in mouse bone marrow demonstrated that DCV SP was restricted to the stem cell lineage(-) Sca-1(+) c-kit(+) cells population, as is Hoechst SP. Pending confirmation by functional analysis of DCV SP cells, these results suggest that DCV efflux identified approximately the same stem cell population as did Hoechst 33342 efflux. Substituting DCV for Hoechst 33342 in the SP technique may, therefore, allow side population analysis on flow cytometers with violet lasers.

  14. Biodegradation of crystal violet using Burkholderia vietnamiensis C09V immobilized on PVA-sodium alginate-kaolin gel beads.

    Science.gov (United States)

    Cheng, Ying; Lin, HongYan; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravi

    2012-09-01

    The strain, Burkholderia vietnamiensis C09V was immobilized on PVA-alginate-kaolin gel beads as a biomaterial to improve the degradation of crystal violet from aqueous solution. The results show that 98.6% (30 mg L(-1)) crystal violet was removed from aqueous solution using immobilized cells on PVA-alginate-kaolin gel beads, while 94.0% crystal violet was removed by free cells after degradation at the pH 5 and 30°C for 30 h. Kinetics studies show that the pseudo-second-order kinetics well described the adsorption of crystal violet on the PVA-alginate-kaolin beads. Biodegradation of crystal violet on immobilized cells was fitted well by first-order reaction kinetics, indicating that CV was adsorbed onto kaolin and followed their degradation by immobilized cells onto the the PVA-alginate-kaolin beads. Characterization with SEM shows that cells attached well to the surface of PVA-alginate-kaolin beads, leading to improved crystal violet transfer from aqueous solution to immobilized cells. In addition, UV-vis show that the absorption peak at 588 nm was reduced by the degraded N-bond linkages, as well as the formation of degrading products were observed by Fourier transform infrared (FTIR). These results suggest that crystal violet was biodegraded to N,N-dimethylaminophenol and Michler's Ketone prior to these intermediates being further degraded. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Geodynamic environments of ultra-slow spreading

    Science.gov (United States)

    Kokhan, Andrey; Dubinin, Evgeny

    2015-04-01

    part of Bransfield rift); 2. During back-arc inter-subduction spreading (Ayu trough, northern Fiji basin), 3. During diffuse back-arc spreading (area on the south-eastern border of Scotia sea), 4. During back-arc spreading under splitting of island arc (northern extremity of Mariana trough). Each of the geodynamic environments is characterized by peculiar topographic, geological and geophysical features forming under the same spreading velocities. Development of ultra-slow spreading in each of these environments results in formation of peculiar extension sedimentary basins.

  16. Detectors in Extreme Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Blaj, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Carini, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Carron, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Haller, G. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hart, P. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Hasi, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Herrmann, S. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Kenney, C. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Segal, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Tomada, A. [SLAC National Accelerator Lab., Menlo Park, CA (United States)

    2015-08-06

    Free Electron Lasers opened a new window on imaging the motion of atoms and molecules. At SLAC, FEL experiments are performed at LCLS using 120Hz pulses with 1012 - 1013 photons in 10 femtoseconds (billions of times brighter than the most powerful synchrotrons). This extreme detection environment raises unique challenges, from obvious to surprising. Radiation damage is a constant threat due to accidental exposure to insufficiently attenuated beam, focused beam and formation of ice crystals reflecting the beam onto the detector. Often high power optical lasers are also used (e.g., 25TW), increasing the risk of damage or impeding data acquisition through electromagnetic pulses (EMP). The sample can contaminate the detector surface or even produce shrapnel damage. Some experiments require ultra high vacuum (UHV) with strict design, surface contamination and cooling requirements - also for detectors. The setup is often changed between or during experiments with short turnaround times, risking mechanical and ESD damage, requiring work planning, training of operators and sometimes continuous participation of the LCLS Detector Group in the experiments. The detectors used most often at LCLS are CSPAD cameras for hard x-rays and pnCCDs for soft x-rays.

  17. Plasma Physics of Extreme Astrophysical Environments

    CERN Document Server

    Uzdensky, Dmitri A

    2014-01-01

    Certain classes of astrophysical objects, namely magnetars and central engines of supernovae and gamma-ray bursts (GRBs), are characterized by extreme physical conditions not encountered elsewhere in the Universe. In particular, they possess magnetic fields that exceed the critical quantum field of 44 teragauss. Figuring out how these complex ultra-magnetized systems work requires understanding various plasma processes, both small-scale kinetic and large-scale magnetohydrodynamic (MHD). However, an ultra-strong magnetic field modifies the underlying physics to such an extent that many relevant plasma-physical problems call for building QED-based relativistic quantum plasma physics. In this review, after describing the extreme astrophysical systems of interest and identifying the key relevant plasma-physical problems, we survey the recent progress in the development of such a theory. We discuss how a super-critical field modifies the properties of vacuum and matter and outline the basic theoretical framework f...

  18. Adsorption of crystal violet onto functionalised multi-walled carbon nanotubes: Equilibrium and kinetic studies.

    Science.gov (United States)

    Sabna, V; Thampi, Santosh G; Chandrakaran, S

    2016-12-01

    Synthetic dyes present in effluent from textile, paper and paint industries contain crystal violet (CV), a known carcinogenic agent. This study investigates the modification of multiwalled carbon nanotubes by acid reflux method and equilibrium and kinetic behaviour of adsorption of CV onto functionalized multi-walled carbon nanotubes (fMWNTs) in batch system. High stability of the fMWNTs suspension in water indicates the hydrophilicity of fMWNTs induced due to the formation of functional groups that make hydrogen bonds with water molecules. fMWNTs were characterized by Fourier Transform Infra Red (FTIR) spectroscopy and the functional groups present on the fMWNTs were confirmed. Characteristic variation was observed in the FTIR spectra of fMWNTs after adsorption of crystal violet onto it. Adsorption characteristics were evaluated as a function of system variables such as contact time, dosage of fMWNTs and initial concentration and pH of the crystal violet solution. Adsorption capacity of fMWNTs and percentage removal of the dye increased with increase in contact time, adsorbent dosage and pH but declined with increase in initial concentration of the dye. fMWNTs showed higher adsorption capacity compared to that of pristine MWNTs. Data showed good fit with the Langmuir and Freundlich isotherm models and the pseudo-second order kinetic model; the maximum adsorption capacity was 90.52mg/g. Kinetic parameters such as rate constants, equilibrium adsorption capacities and regression coefficients were estimated. Results indicate that fMWNTs are an effective adsorbent for the removal of crystal violet from aqueous solution.

  19. Violet laser power sensor based on micro-fiber coated with methyl blue-functionalized reduced graphene oxide

    Science.gov (United States)

    Tian, Zhengwen; Zhang, Jun; Yang, Bing; Yu, Jianhui; Chen, Zhe; Tang, Jieyuan; Luo, Yunhan; Cai, Xiang; Tan, Shaozao; Lu, Huihui

    2014-05-01

    A novel all fiber-optic power sensor of violet laser based on methyl blue-functionalized reduced graphene oxide (MB-rGO) film coated on a microfiber (MF) was proposed. The experiments show that when the violet laser illuminating onto the MB-rGO film with power variation from 0.03mw to 12.8mw, the transmitted optical power of the MF changes with a relative variation of ~2.7dB. The novel power sensor of violet laser possesses a sensitivity of ~0.22dB/mw in 1550nm. Furthermore, the MB-rGO-based all fiber-optic violet power sensor is easy to fabricate, compatible with fiberoptic systems and possesses high potentiality in photonics applications such as all fiber-optic broadband sensors, switches and modulators.

  20. Visual function improvement using photocromic and selective blue-violet light filtering spectacle lenses in patients affected by retinal diseases

    National Research Council Canada - National Science Library

    L Colombo; E Melardi; P Ferri; G Montesano; S Samir Attaalla; F Patelli; S De Cilla; G Savaresi; L Rossetti

    2017-01-01

    Background To evaluate functional visual parameters using photocromic and selective blue-violet light filtering spectacle lenses in patients affected by central or peripheral scotoma due to retinal diseases...

  1. Fixed-bed column studies on biosorption of crystal violet from aqueous solution by Citrullus lanatus rind and Cyperus rotundus

    National Research Council Canada - National Science Library

    Bharathi, Kandaswamy Suyamboo; Ramesh, SriKrishna Perumal Thanga

    2013-01-01

    In this study, fixed-bed column experiments were performed to investigate the biosorption potential of two agricultural wastes, Citrullus lanatus rind and Cyperus rotundus to remove Crystal violet (CV...

  2. 75 FR 29718 - Carbazole Violet Pigment 23 From India and the People's Republic of China: Continuation of...

    Science.gov (United States)

    2010-05-27

    ... of Sales at Less Than Fair Value and Antidumping Duty Order: Carbazole Violet Pigment 23 From India...-proprietary information. In this case, the brackets are simply part of the chemical nomenclature....

  3. Tertiary structure and spectral tuning of UV and violet pigments in vertebrates

    Science.gov (United States)

    Yokoyama, Shozo; Starmer, William T.; Takahashi, Yusuke; Tada, Takashi

    2010-01-01

    Many vertebrate species use ultraviolet (UV) vision for such behaviors as mating, foraging, and communication. UV vision is mediated by UV-sensitive visual pigments, which have the wavelengths of maximal absorption (λmax) at ~360 nm, whereas violet (or blue) vision is mediated by orthologous pigments with λmax values of 390–440 nm. It is widely believed that amino acids in transmembrane (TM) I–III are solely responsible for the spectral tuning of these SWS1 pigments. Recent molecular analyses of SWS1 pigments, however, show that amino acids in TM IV–VII are also involved in the spectral tuning of these pigments through synergistic interactions with those in TM I–III. Comparisons of the tertiary structures of UV and violet pigments reveal that the distance between the counterion E113 in TM III and amino acid sites 87–93 in TM II is narrower for UV pigments than for violet pigments, which may restrict the access of water molecules to the Schiff base pocket and deprotonate the Schiff base nitrogen. Both mutagenesis analyses of E113Q and quantum chemical calculations strongly suggest that unprotonated Schiff base-linked chromophore is responsible for detecting UV light. PMID:16343816

  4. Determination of optical constants and nonlinear optical coefficients of Violet 1-doped polyvinyl alcohol thin film

    Indian Academy of Sciences (India)

    Hussain A Badran; Alaa Y Al-Ahmad; Qusay M Ali Hassan; Chassib A Emshary

    2016-01-01

    The optical properties of Violet 1-doped polyvinyl alcohol (PVA) have been investigated using Wemble and Didomenico (WD) method. The optical constants such as refractive index , the dispersion energy , the oscillation energy 0, the lattice dielectric constant ∞, light frequency dielectric constant 0 and the ratio of carrier concentration to the effective mass /* have been determined using reflection spectra in the wavelength range 300–900 nm. The singlebeam Z-scan technique was used to determine the nonlinear optical properties of Violet 1:polyvinylalcohol (PVA) thin film. The experiments were performed using continuous wave (cw) laser with a wavelength of 635 nm. The calculated nonlinear refractive index of the film, $n_{2} = -2.79 \\times 10^{-7}$ cm2/Wand nonlinear absorption coefficient, $\\beta = 6.31\\times10^{−3}$ cm/W. Optical limiting characteristics of the dye-doped polymer film was studied. The result reveals that Violet 1 can be a promising material for optical limiting applications.

  5. A violet emission in ZnS:Mn,Eu: Luminescence and applications for radiation detection

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Lun; Chen, Wei, E-mail: weichen@uta.edu [Department of Physics and the SAVANT Center, The University of Texas at Arlington, Arlington, Texas 76019-0059 (United States); Jiang, Ke [Center for Biofrontiers Institute, University of Colorado at Colorado Springs, 1420 Austin Bluffs Pkwy., Colorado Springs, Colorado 80918 (United States); Liu, Xiao-tang [Department of Physics and the SAVANT Center, The University of Texas at Arlington, Arlington, Texas 76019-0059 (United States); Department of Applied Chemistry, College of Science, South China Agricultural University, Guangzhou 510642 (China)

    2014-03-14

    We prepared manganese and europium co-doped zinc sulfide (ZnS:Mn,Eu) phosphors and used them for radiation detection. In addition to the red fluorescence at 583 nm due to the d-d transition of Mn ions, an intense violet emission at 420 nm is newly observed in ZnS:Mn,Eu phosphors. The emission is related to Eu{sup 2+} doping but only appears at certain Eu{sup 2+} concentrations. It is found that the intensity of the 420 nm violet fluorescence is X-ray does-dependent, while the red fluorescence of 583 nm is not. The ratio of fluorescence intensities at 420 nm and 583 nm has been monitored as a function of X-ray doses that exposed upon the ZnS:Mn,Eu phosphors. Empirical formulas are provided to estimate the doses of applied X-ray irradiation. Finally, possible mechanisms of X-ray irradiation induced fluorescence quenching are discussed. The intense 420 nm emission not only provides a violet light for solid state lighting but also offers a very sensitive method for radiation detection.

  6. Extreme sports: injuries and medical coverage.

    Science.gov (United States)

    Young, Craig C

    2002-10-01

    Extreme sports (including in-line skating, snowboarding, mountain bicycling, extreme skiing, rock climbing, indoor tackle football, kickboxing, skateboarding, and ultra-endurance racing) are growing in popularity. Often these sports are designed to expose athletes to greater thrills and risks than are found in traditional sporting activities. Despite this increased risk of injury, athletes competing in these sports often have little or no formal medical coverage. This article reviews what is known about this emerging area of sports medicine to assist physicians in preparing for medical coverage of these athletes and their competitions.

  7. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

    Ultra Wide Band Technology (UWB) has reached a level of maturity that allows us to offer wireless links with either high or low data rates. These wireless links are frequently associated with a location capability for which ultimate accuracy varies with the inverse of the frequency bandwidth. Using time or frequency domain waveforms, they are currently the subject of international standards facilitating their commercial implementation. Drawing up a complete state of the art, Ultra Wide Band Antennas is aimed at students, engineers and researchers and presents a summary of internationally recog

  8. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2002-07-30

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems, including foamed and sodium silicate slurries. During this project quarter, a comparison study of the three cement systems examined the effect that cement drillout has on the three cement systems. Testing to determine the effect of pressure cycling on the shear bond properties of the cement systems was also conducted. This report discusses testing that was performed to analyze the alkali-silica reactivity of ULHS in cement slurries.

  9. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2001-10-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). Work reported herein addresses tasks performed in the fourth quarter as well as the other three quarters of the past year. The subjects that were covered in previous reports and that are also discussed in this report include: Analysis of field laboratory data of active cement applications from three oil-well service companies; Preliminary findings from a literature review focusing on problems associated with ultra-lightweight cements; Summary of pertinent information from Russian ultra-lightweight cement literature review; and Comparison of compressive strengths of ULHS systems using ultrasonic and crush methods Results reported from the fourth quarter include laboratory testing of ULHS systems along with other lightweight cement systems--foamed and sodium silicate slurries. These comparison studies were completed for two different densities (10.0 and 11.5 lb/gal) and three different field application scenarios. Additional testing included the mechanical properties of ULHS systems and other lightweight systems. Studies were also performed to examine the effect that circulation by centrifugal pump during mixing has on breakage of ULHS.

  10. Weighing Ultra-Cool Stars

    Science.gov (United States)

    2004-05-01

    Large Ground-Based Telescopes and Hubble Team-Up to Perform First Direct Brown Dwarf Mass Measurement [1] Summary Using ESO's Very Large Telescope at Paranal and a suite of ground- and space-based telescopes in a four-year long study, an international team of astronomers has measured for the first time the mass of an ultra-cool star and its companion brown dwarf. The two stars form a binary system and orbit each other in about 10 years. The team obtained high-resolution near-infrared images; on the ground, they defeated the blurring effect of the terrestrial atmosphere by means of adaptive optics techniques. By precisely determining the orbit projected on the sky, the astronomers were able to measure the total mass of the stars. Additional data and comparison with stellar models then yield the mass of each of the components. The heavier of the two stars has a mass around 8.5% of the mass of the Sun and its brown dwarf companion is even lighter, only 6% of the solar mass. Both objects are relatively young with an age of about 500-1,000 million years. These observations represent a decisive step towards the still missing calibration of stellar evolution models for very-low mass stars. PR Photo 19a/04: Orbit of the ultra-cool stars in 2MASSW J0746425+2000321. PR Photo 19b/04: Animated Gif of the orbital motion. Telephone number star Even though astronomers have found several hundreds of very low mass stars and brown dwarfs, the fundamental properties of these extreme objects, such as masses and surface temperatures, are still not well known. Within the cosmic zoo, these ultra-cool stars represent a class of "intermediate" objects between giant planets - like Jupiter - and "normal" stars less massive than our Sun, and to understand them well is therefore crucial to the field of stellar astrophysics. The problem with these ultra-cool stars is that contrary to normal stars that burn hydrogen in their central core, no unique relation exists between the luminosity of the

  11. Magnetic solid-phase extraction for determination of the total malachite green, gentian violet and leucomalachite green, leucogentian violet in aquaculture water by high-performance liquid chromatography with fluorescence detection.

    Science.gov (United States)

    Zhao, Jiao; Wei, Daqiao; Yang, Yaling

    2016-06-01

    In this study, magnetic multi-walled carbon nanotube nanoparticles were synthesized and used as the adsorbent for the sums of malachite green, gentian violet and leucomalachite green, leucogentian violet in aquaculture water samples followed by high performance liquid chromatography with fluorescence detection. This method was based on in situ reduction of chromic malachite green, gentian violet to colorless leucomalachite green, leucogentian violet with potassium borohydride, respectively. The obtained adsorbent combines the advantages of carbon nanotubes and Fe3 O4 nanoparticles in one material for separation and preconcentration of the reductive dyes in aqueous media. The structure and properties of the prepared nanoparticles were characterized by transmission and scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared spectroscopy. The main parameters affecting the adsorption recoveries were investigated and optimized, including reducing agent concentration, type and amount of sorbent, sample pH, and eluting conditions. Under the optimum conditions, the limits of detection in this method were 0.22 and 0.09 ng/mL for malachite green and gentian violet, respectively. Product recoveries ranged from 87.0 to 92.8% with relative standard deviations from 4.6 to 5.9%. The results indicate that the sorbent is a suitable material for the removal and concentration of triphenylmethane dyes from polluted environmental samples.

  12. Adsorption of Crystal violet on raw and acid-treated montmorillonite, K10, in aqueous suspension.

    Science.gov (United States)

    Sarma, Gautam Kumar; Sen Gupta, Susmita; Bhattacharyya, Krishna G

    2016-04-15

    Crystal violet is used as a dye in cotton and silk textiles, paints and printing ink. The dye is hazardous and exposure to it may cause permanent injury to the cornea and conjunctiva including permanent blindness, and in severe cases, may lead to respiratory and kidney failure. The present work describes removal of Crystal violet from aqueous solution by adsorption on raw and acid-treated montmorillonite, K10. The clay mineral was treated with 0.25 and 0.50 M sulfuric acid and the resulting materials were characterized by XRD, zeta potential, SEM, FTIR, cation exchange capacity, BET surface area and pore volume measurements. The influences of pH, interaction time, adsorbent amount, and temperature on adsorption were monitored and explained on the basis of physico-chemical characteristics of the materials. Basic pH generally favors adsorption but considerable removal was possible even under neutral conditions. Adsorption was very rapid and equilibrium could be attained in 180 min. The kinetics conformed to second order model. Langmuir monolayer adsorption capacity of raw montmorillonite K10 was 370.37 mg g(-1) whereas 0.25 M and 0.50 M acid treated montmorillonite K10 had capacities of 384.62 and 400.0 mg g(-1) respectively at 303 K. Adsorption was exothermic and decreased in the temperature range of 293-323 K. Thermodynamically, the process was spontaneous with Gibbs energy decreasing with rise in temperature. The results suggest that montmorillonite K10 and its acid treated forms would be suitable for removing Crystal violet from aqueous solution. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2002-01-23

    The objective of this project is to develop an improved ultra-lightweight cement using ultra-lightweight hollow glass spheres (ULHS). This report includes results from laboratory testing of ULHS systems along with other lightweight cement systems: foamed and sodium silicate slurries. Comparison studies of the three cement systems examined several properties: tensile strength, Young's modulus, water permeability, and shear bond. Testing was also done to determine the effect that temperature cycling has on the shear bond properties of the cement systems. In addition, analysis was carried out to examine alkali silica reactivity of slurries containing ULHS. Data is also presented from a study investigating the effects of mixing and pump circulation on breakage of ULHS. Information is also presented about the field application of ULHS in cementing a 7-in. intermediate casing in south Texas.

  14. Computational Chemistry Approach to Interpret the Crystal Violet Adsorption on Golbasi Lignite Activated Carbon

    Science.gov (United States)

    Depci, Tolga; Sarikaya, Musa; Prisbrey, Keith A.; Yucel, Aysegul

    2016-10-01

    In this paper, adsorption mechanism of Crystal Violet (CV) dye from the aqueous solution on the activated carbon prepared from Golbasi lignite was explained and interpreted by a computational chemistry approach and experimental studies. Molecular dynamic simulations and Ab initio frontier orbital analysis indicated relatively high energy and electron transfer processes during adsorption, and molecular dynamics simulations showed CV dye molecules moving around on the activated carbon surface after adsorption, facilitating penetration into cracks and pores. The experimental results supported to molecular dynamic simulation and showed that the monolayer coverage occurred on the activated carbon surface and each CV dye ion had equal sorption activation energy.

  15. Adsorption Capability of Cationic Dyes (Methylene Blue and Crystal Violet) onto Poly-γ-glutamic Acid.

    Science.gov (United States)

    Ogata, Fumihiko; Nagai, Noriaki; Kawasaki, Naohito

    2017-01-01

    In this study, the adsorption capability of cationic dyes, which were methylene blue and crystal violet, by poly-γ-glutamic acid (PGA) in a single or binary solution system was investigated. The effect of the molecular weight of PGA, initial dye concentration, solution pH, and temperature on the adsorption of dyes was evaluated. The adsorption mechanism of dyes onto PGA was the interaction between -COOH group on the PGA surface and the polarity groups of dyes. These results indicated that PGA is useful for removal of dyes and cationic organic compounds from a single or binary solution system.

  16. Towards dating Quaternary sediments using the quartz Violet Stimulated Luminescence (VSL) signal

    DEFF Research Database (Denmark)

    Ankjærgaard, C.; Jain, Mayank; Wallinga, J.

    2013-01-01

    Quartz optically stimulated luminescence (OSL) dating is widely used to determine the time of deposition and burial of Late Quaternary sediments. Application of the method is usually limited to the past 150,000 years due to early saturation of the OSL signal. Here we explore the potential to date...... Quaternary sediments using the violet (402 nm) stimulated luminescence (VSL) signal of quartz.We develop and test a new post-blue VSL single aliquot regenerative dose dating protocol, and demonstrate that the VSL signal originates from a deep trap at about 1.9 eV with a thermal lifetime of 1011 years at 10...

  17. Violet/blue photoluminescence from CeO2 thin film

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    CeO2 thin film was fabricated by dual ion beam epitaxial technique. The violet/blue PL at room temperature and lower temperature was observed from the CeO2 thin film. After the analysis of crystal structure and valence in the compound was carried out by the XRD and XPS technique, it was inferred that the origin of CeO2 PL was due to the electrons transition from Ce4f band to O2p band and the defect level to O2p band. And these defects levels were located in the range of 1 eV around Ce4f band.

  18. High light extraction efficiency in bulk-GaN based volumetric violet light-emitting diodes

    Energy Technology Data Exchange (ETDEWEB)

    David, Aurelien, E-mail: adavid@soraa.com; Hurni, Christophe A.; Aldaz, Rafael I.; Cich, Michael J.; Ellis, Bryan; Huang, Kevin; Steranka, Frank M.; Krames, Michael R. [Soraa Inc., 6500 Kaiser Dr., Fremont, California 94555 (United States)

    2014-12-08

    We report on the light extraction efficiency of III-Nitride violet light-emitting diodes with a volumetric flip-chip architecture. We introduce an accurate optical model to account for light extraction. We fabricate a series of devices with varying optical configurations and fit their measured performance with our model. We show the importance of second-order optical effects like photon recycling and residual surface roughness to account for data. We conclude that our devices reach an extraction efficiency of 89%.

  19. Matrix dependent changes in metachromasy of crystal violet in Langmuir-Blodgett films

    Science.gov (United States)

    Shil, Ashis; Saha, Mitu; Debnath, Chandan; Hussain, S. A.; Bhattacharjee, D.

    2016-11-01

    This communication reports the effect of building matrices and nano clay platelets on the aggregation pattern of a water soluble cationic fluorescent dye Crystal Violet (CV) in Langmuir-Blodgett (LB) Films. When stearic acid (SA) was used as a building matrix, pressure induced changes in metachromasy was observed in the SA-CV complex LB films with a characteristic J-band formed at the longer wavelength side. On the other hand, clay incorporated hybrid LB films showed high degree of control over H-dimeric band. Isotherm characteristics, Brewster Angle Microscopic (BAM) images, UV-vis absorption and fluorescence characteristic studies were employed to investigate this result.

  20. Orange and IR to violet up-conversion processes in Nd:ZBLAN glasses

    Science.gov (United States)

    Klimczak, M.; Malinowski, M.; Piramidowicz, R.

    2009-10-01

    In this work we investigate, compare and discuss UV and violet emission behaviour under pulsed, multi-photon orange and infra-red excitation in Nd 3+ doped ZBLAN samples of different concentrations ranging from 0.3 to 5 mol.%. Supported by the obtained spectroscopic results, orange and IR excitation schemes were proposed and verified by time dependent rate equation model, which has been employed to confirm the nature of observed processes. Proposed model returns fitting results which qualitatively reflect the experimentally obtained fluorescence decays.

  1. Room-temperature fluorozirconate glass fiber laser in the violet (412 nm).

    Science.gov (United States)

    Funk, D S; Carlson, J W; Eden, J G

    1995-07-01

    Continuous oscillation on the (2)P(3/2) ? (4)I(11/2) transition of Nd(3+) in a f luorozirconate glass (ZBLAN) fiber at room temperature has been observed. When pumped at ~590 nm, a Nd:ZBLAN f iber 39 cm in length lases in the violet at 412 nm and produces ~0.5 mW of power for 320 mW of pump power and a cavity output coupling of 0.4%. The breadth of the laser's excitation spectrum is ~12 nm (581-593 nm).

  2. Ultra high resolution tomography

    Energy Technology Data Exchange (ETDEWEB)

    Haddad, W.S.

    1994-11-15

    Recent work and results on ultra high resolution three dimensional imaging with soft x-rays will be presented. This work is aimed at determining microscopic three dimensional structure of biological and material specimens. Three dimensional reconstructed images of a microscopic test object will be presented; the reconstruction has a resolution on the order of 1000 A in all three dimensions. Preliminary work with biological samples will also be shown, and the experimental and numerical methods used will be discussed.

  3. Ultra-Wideband Radio

    Directory of Open Access Journals (Sweden)

    Won Namgoong

    2005-03-01

    Full Text Available The application of ultra-wideband (UWB technology to low-cost short-range communications presents unique challenges to the communications engineer. The impact of the US FCC's regulations and the characteristics of the low-power UWB propagation channels are explored, and their effects on UWB hardware design are illustrated. This tutorial introduction includes references to more detailed explorations of the subject.

  4. Tensile and Flexural Properties of Ultra High Toughness Cemontious Composite

    Institute of Scientific and Technical Information of China (English)

    LI Hedong; XU Shilang; Christopher K Y Leung

    2009-01-01

    The tensile and flexural properties of polyvinyl alcohol(PVA)fiber reinforced ultra high toughness cementitious composite(UHTCC)were investigated.The composite,tested at the age of 14 d,28 d and 56 d,shows extremely remarkable pseudo strain hardening behavior,saturated mul-tiple cracking and ultra high ultimate strain capacity above 4%under uniaxial loading.Also,the cor-responding crack widths are controlled under 50 μm even at 56 days age.In the third point bending tests on thin plate specimens,the composite shows ultra high flexural ductility and multiple cracking on the tension surface.The high ultimate flexural strength/first tensile strength ratio of about 5 verifies the pseudo strain hardening behavior of UHTCC.SEM observation on fracture surfaces provides in-direct evidence of optimal design for the composite.

  5. ULTRA-LIGHTWEIGHT CEMENT

    Energy Technology Data Exchange (ETDEWEB)

    Fred Sabins

    2001-04-15

    The objective of this project is to develop an improved ultra-lightweight cement using ultralight hollow glass spheres (ULHS). Work reported herein addresses Task 1: Assess Ultra-Lightweight Cementing Problems and Task 3: Test Ultra-Lightweight Cements. Results reported this quarter include a review and summary of Halliburton Energy Services (HES) and BJ Services historical performance data for lightweight cement applications. These data are analyzed and compared to ULHS cement and foamed cement performances. Similar data is expected from Schlumberger, and an analysis of this data will be completed in the following phases of the project. Quality control testing of materials used to formulate ULHS cements in the laboratory was completed to establish baseline material performance standards. A testing protocol was developed employing standard procedures as well as procedures tailored to evaluate ULHS and foamed cement. This protocol is presented and discussed. Results of further testing of ULHS cements are presented along with an analysis to establish cement performance design criteria to be used during the remainder of the project. Finally, a list of relevant literature on lightweight cement performance is compiled for review during the next quarter.

  6. Ultra reliability at NASA

    Science.gov (United States)

    Shapiro, Andrew A.

    2006-01-01

    Ultra reliable systems are critical to NASA particularly as consideration is being given to extended lunar missions and manned missions to Mars. NASA has formulated a program designed to improve the reliability of NASA systems. The long term goal for the NASA ultra reliability is to ultimately improve NASA systems by an order of magnitude. The approach outlined in this presentation involves the steps used in developing a strategic plan to achieve the long term objective of ultra reliability. Consideration is given to: complex systems, hardware (including aircraft, aerospace craft and launch vehicles), software, human interactions, long life missions, infrastructure development, and cross cutting technologies. Several NASA-wide workshops have been held, identifying issues for reliability improvement and providing mitigation strategies for these issues. In addition to representation from all of the NASA centers, experts from government (NASA and non-NASA), universities and industry participated. Highlights of a strategic plan, which is being developed using the results from these workshops, will be presented.

  7. A temperature response function for modeling leaf growth and development of the African violet (Saintpaulia ionantha Wendl.

    Directory of Open Access Journals (Sweden)

    Streck Nereu Augusto

    2004-01-01

    Full Text Available Response functions used in crop simulation models are usually different for different physiological processes and cultivars, resulting in many unknown coefficients in the response functions. This is the case of African violet (Saintpaulia ionantha Wendl., where a generalized temperature response for leaf growth and development has not been developed yet. The objective of this study was to develop a generalized nonlinear temperature response function for leaf appearance rate and leaf elongation rate in African violet. The nonlinear function has three coefficients, which are the cardinal temperatures (minimum, optimum, and maximum temperatures. These coefficients were defined as 10, 24, and 33ºC, based on the cardinal temperatures of other tropical species. Data of temperature response of leaf appearance rate and leaf elongation rate in African violet, cultivar Utah, at different light levels, which are from published research, were used as independent data for evaluating the performance of the nonlinear temperature response function. The results showed that a generalized nonlinear response function can be used to describe the temperature response of leaf growth and development in African violet. These results imply that a reduction in the number of input data required in African violet simulation models is possible.

  8. Ultra-broadband and ultra-fast optical signal processing

    DEFF Research Database (Denmark)

    Oxenløwe, Leif Katsuo

    2015-01-01

    We have recently seen that nanowires can provide unparalleled optical signal processing (OSP) bandwidth and provide ultra-fast operation as well. Utilising the ultra-broad OSP bandwidth for e.g. optical time lenses allows for energy-efficient optical switching. © 2015 OSA.......We have recently seen that nanowires can provide unparalleled optical signal processing (OSP) bandwidth and provide ultra-fast operation as well. Utilising the ultra-broad OSP bandwidth for e.g. optical time lenses allows for energy-efficient optical switching. © 2015 OSA....

  9. Extremely Preterm Birth

    Science.gov (United States)

    ... Events Advocacy For Patients About ACOG Extremely Preterm Birth Home For Patients Search FAQs Extremely Preterm Birth ... Spanish FAQ173, June 2016 PDF Format Extremely Preterm Birth Pregnancy When is a baby considered “preterm” or “ ...

  10. Photocatalytic studies of crystal violet dye using mn doped and PVP capped ZnO nanoparticles.

    Science.gov (United States)

    Mittal, Manish; Sharma, Manoj; Pandey, O P

    2014-04-01

    Mn (0.5%, 1%, 1.5% and 2%) doped and undoped ZnO nanoparticles (NPs) capped with PVP (1.0%) were successfully synthesized via co-precipitation approach using zinc acetate, sodium hydroxide and manganese acetate as precursors. Structural analysis was performed by XRD confirming phase purity and crystalline wurtzite structure. TEM results show average particle size 15-20 nm and 22-25 nm for Mn (1%) and Mn (2%) doped ZnO NPs respectively. Manganese (Mn) doping has led to reduction in band gap which facilitate the absorption of radiation in visible region. The Photocatalytic activity of undoped and Mn (0.5%,1%,1.5% and 2%) doped NPs was analyzed via degradation of crystal violet (CV) dye. The crystal violet decomposition rate of undoped and Mn doped NPs were studied under UV-visible region. It is observed from degradation studies that the doping has a pronounced effect on the photocatalytic activity of ZnO NPs. Kinetic studies shows that photo degradation of CV follow a pseudo first-order kinetic law. Experiments for reusability of Mn (1%) doped with PVP (1%) capped ZnO were also performed to determine the stability of as prepared sample. It shows an increase in catalytic activity of NPs by small amount when exposed to UV irradiation for 3 h. Photoluminescence and UV-Visible absorption spectroscopy studies were also performed for studying the effect of UV irradiation on the surface of ZnO NPs.

  11. Liquid phase adsorption of Crystal violet onto activated carbons derived from male flowers of coconut tree.

    Science.gov (United States)

    Senthilkumaar, S; Kalaamani, P; Subburaam, C V

    2006-08-25

    Adsorption of Crystal violet, a basic dye onto phosphoric and sulphuric acid activated carbons (PAAC and SAAC), prepared from male flowers coconut tree has been investigated. Equilibrium data were successfully applied to study the kinetics and mechanism of adsorption of dye onto both the carbons. The kinetics of adsorption was found to be pseudo second order with regard to intraparticle diffusion. The pseudo second order is further supported by the Elovich model, which in turn intensifies the fact of chemisorption of dye onto both the carbons. Quantitative removal of dye at higher initial pH of dye solution reveals the basic nature of the Crystal violet and acidic nature of the activated carbons. Influence of temperature on the removal of dye from aqueous solution shows the feasibility of adsorption and its endothermic nature. Mass transfer studies were also carried out. The adsorption capacities of both the carbons were found to be 60.42 and 85.84 mg/g for PAAC and SAAC, respectively. Langmuir's isotherm data were used to design single-stage batch adsorption model.

  12. Adsorption and desorption characteristics of crystal violet in bottom ash column

    Directory of Open Access Journals (Sweden)

    Puthiya Veetil Nidheesh

    2012-06-01

    Full Text Available This study described adsorption of Crystal Violet (CV by bottom ash in fixed-bed column mode. Equilibrium of adsorption was studied in batch mode for finding adsorption capacity of bottom ash. In fixed bed column adsorption, the effects of bed height, feed flow rate, and initial concentration were studied by assessing breakthrough curve. The slope of the breakthrough curve decreased with increasing bed height. The breakthrough time and exhaustion time were decreased with increasing influent CV concentration and flow rates. The effect of bed depth, flow rate and CV concentration on the adsorption column design parameters were analyzed. Bed depth service time (BDST model was applied for analysis of crystal violet adsorption in the column. The adsorption capacity of bottom ash was calculated at 10% breakthrough point for different flow rates and concentrations. Desorption studies reveals that recovery of CV from bottom ash was effective by using CH3COOH than H2SO4, NaOH, HCl and NaCl solutions.

  13. ADSORPTION AND DESORPTION CHARACTERISTICS OF CRYSTAL VIOLET IN BOTTOM ASH COLUMN

    Directory of Open Access Journals (Sweden)

    Puthiya Veetil Nidheesh

    2012-01-01

    Full Text Available This study described adsorption of Crystal Violet (CV by bottom ash in fixed-bed column mode. Equilibrium of adsorption was studied in batch mode for finding adsorption capacity of bottom ash. In fixed bed column adsorption, the effects of bed height, feed flow rate, and initial concentration were studied by assessing breakthrough curve. The slope of the breakthrough curve decreased with increasing bed height. The breakthrough time and exhaustion time were decreased with increasing influent CV concentration and flow rates. The effect of bed depth, flow rate and CV concentration on the adsorption column design parameters were analyzed. Bed depth service time (BDST model was applied for analysis of crystal violet adsorption in the column. The adsorption capacity of bottom ash was calculated at 10% breakthrough point for different flow rates and concentrations. Desorption studies reveals that recovery of CV from bottom ash was effective by using CH3COOH than H2SO4, NaOH, HCl and NaCl solutions.

  14. Enhanced tetrazolium violet reduction of Salmonella spp. by magnesium addition to the culture media.

    Science.gov (United States)

    Junillon, Thomas; Morand, Lucie; Flandrois, Jean Pierre

    2014-09-01

    Tetrazolium salts (TTZ), such as tetrazolium violet (TV), have been widely used for microbiological studies. The formation of the colored formazan product due to bacterial reduction of the uncolored reagent is extensively exploited to stain cells or colonies in agar or on filters. But an important toxic effect of tetrazolium salts on bacteria exists that limits their use at high concentrations, impairing the efficient staining of the colonies. This is especially the case for Salmonella spp. where we observed, using a classic photometric approach and mathematical modeling of the growth, an important impact of tetrazolium violet on the apparent growth rate below the inhibitory concentration. In this study, we demonstrate that adding magnesium to the medium in the presence of TV leads to a significant increase in the apparent growth rate. Moreover, when higher TV concentrations are used which lead to total inhibition of Salmonella strains, magnesium addition to the culture media allows growth and TV reduction. This effect of magnesium may allow the use of higher TTZ concentrations in liquid growth media and enhance bacteria detection capabilities.

  15. Quantification of antidepressants and antipsychotics in human serum by precipitation and ultra high pressure liquid chromatography-tandem mass spectrometry

    DEFF Research Database (Denmark)

    Hasselstrøm, Jørgen Bo

    2011-01-01

    for therapeutic drug monitoring. The method was developed to replace old techniques which applied solid phase extraction and ultra-violet detection. The old methods had reached their limit of capacity regarding the number of samples and co-medicated drugs interfering with the detection. Serum samples were...... precipitated with zinc sulphate and methanol containing a stable isotope labelled analog for each analyte. Quantitative analysis was performed by ultra high pressure liquid chromatography combined with a tandem mass spectrometer using a Zorbax SB-C8 column (2.0×50mm; 1.8m) with a mobile phase consisting of 0...... time, reduced interference from other drugs, avoided acetonitrile usage, and reduced the amount of serum needed for analysis 50-fold....

  16. Red, violet and upconversion luminescence of Eu/Sm codoped sol gel SiO2-TiO2

    Science.gov (United States)

    Azzouz, I. M.; Klein, Lisa C.

    2012-12-01

    Rare earth (Eu/Sm) doped silica-titania composite systems were sensitized by sol-gel method in solid and powder forms. The crystalline phase has been identified for the annealed samples at 1000 °C by X-ray diffraction (XRD). The bonding formation of the host matrix was examined by Fourier transform infrared (FTIR). The fingerprint transition lines of Eu3+ ions, with the main emission line at 616 nm, are recorded for the samples. Improvement in Eu3+ luminescence has been recorded by adding Sm3+ and by samples. Violet emission is observed under UV irradiation. Violet-blue upconversion luminescence is recorded at room temperature.

  17. Multidimensional extremal dependence coefficients

    OpenAIRE

    2017-01-01

    Extreme values modeling has attracting the attention of researchers in diverse areas such as the environment, engineering, or finance. Multivariate extreme value distributions are particularly suitable to model the tails of multidimensional phenomena. The analysis of the dependence among multivariate maxima is useful to evaluate risk. Here we present new multivariate extreme value models, as well as, coefficients to assess multivariate extremal dependence.

  18. The European Extreme Right and Religious Extremism

    Directory of Open Access Journals (Sweden)

    Jean-Yves Camus

    2007-12-01

    Full Text Available The ideology of the Extreme Right in Western Europe is rooted in Catholic fundamentalism and Counter-Revolutionary ideas. However, the Extreme Right, like all other political families, has had to adjust to an increasingly secular society. The old link between religion and the Extreme Right has thus been broken and in fact already was when Fascism overtook Europe: Fascism was secular, sometimes even anti-religious, in its essence. Although Catholic fundamentalists still retain strong positions within the apparatus of several Extreme Right parties (Front National, the vote for the Extreme Right is generally weak among regular churchgoers and strong among non-believers. In several countries, the vote for the Extreme Right is stronger among Protestant voters than among Catholics, since while Catholics may support Christian-Democratic parties, there are very few political parties linked to Protestant churches. Presently, it also seems that Paganism is becoming the dominant religious creed within the Extreme Right. In a multicultural Europe, non-Christian forms of religious fundamentalism such as Islamism also exist with ideological similarities to the Extreme Right, but this is not sufficient to categorize Islamism as a form of Fascism. Some Islamist groups seek alliances with the Extreme Right on the basis of their common dislike for Israel and the West, globalization and individual freedom of thought.

  19. Microbial Manganese Oxidation in Saltmarsh Surface Sediments Using a Leuco Crystal Violet Manganese Oxide Detection Technique

    Science.gov (United States)

    Spratt, Henry G.; Siekmann, Ellen C.; Hodson, Robert E.

    1994-01-01

    Microbial manganese (Mn) oxide production in surface sediments of a Georgia saltmarsh was directly measured using an assay involving the oxidation of 4,4',4″-methylidynetris (N,N-dimethylaniline), leuco crystal violet (LCV), by Mn oxides to produce crystal violet. The assay exhibits high specificity for Mn oxides without interference by Mn(II) and is sufficiently sensitive to determine rates of Mn oxidation in surface sediment or saltmarsh creek water suspensions. Sample salinity affects crystal violet absorbance in the 0-25 salinity range and must be corrected for in Mn oxide determinations for estuarine samples of variable salinity. Other oxidants found to oxidize LCV slowly included Cl(I), Cr(III), I(V), Fe(III), and Mn(III), although the sensitivity of the assay for Mn(IV) oxides was found to be seven times greater than for Mn(III), and at least 100 times greater than for any of the other oxidants. Rates of abiotic Mn oxide production in sediment suspensions treated with either sodium azide or formalin, or autoclaved, were much slower than rates determined for untreated sediments. Sodium azide (7·7 mM) inhibited Mn oxide production in these sediment suspensions to rates between 5 and 10% of the rates of Mn oxidation determined for unamended suspensions. Manganese oxidation was highly temperature dependent, with maximal rates on a dry weight basis (8·9 nmol mg dwt -1 h -1), occurring at 60°C, and negligible activity at 100 and 0°C. Rates were also dependent on sample pH, with maximal rates at pH 6·7, decreasing to near 0 as the pH was lowered to approximately 3·0. For Mn(II) concentrations ranging from 9 to 91 μM, rates of Mn oxide production were independent of Mn(II) concentration, while Mn oxide production was inhibited at concentrations greater than 91 μM (e.g. by 25-40% at 450 μM). Rates of microbial Mn oxide production in surface sediment/saltmarsh creek water suspensions incubated under natural conditions of temperature, pH, and Mn

  20. Production ultra propre

    CERN Document Server

    Morvan, Gilles

    2011-01-01

    L'ultra propreté se caractérise par l'absence de particules et la maîtrise de la contamination dans un environnement défini. Largement appliquée dans diverses industries (pharmacie, cosmétiques, dispositifs médicaux, chimie fine, biotechnologies, électronique et secteurs de pointe, agroalimentaire, plasturgie…), la technicité dans ce domaine est élevée, car principalement liée à la maîtrise des différentes sources de contaminations (eau, air ambiant, fluides, etc.). Véritable guide pratique, cet ouvrage détaille les points techniques essentiels pour permettre à l’ingénieur de trouver des solutions adéquates à chaque type de projet. La démarche passe par la rédaction de spécifications rigoureuses pour : - l’eau, essentielle à toutes productions, - les équipements de production ultra propre, - la démarche qualité et environnementale, - la démarche de suivi du projet.

  1. Adsorption of Crystal Violet on Activated Carbon Prepared from Coal Flotation Concentrate

    Science.gov (United States)

    Aydogmus, Ramazan; Depci, Tolga; Sarikaya, Musa; Riza Kul, Ali; Onal, Yunus

    2016-10-01

    The objective of this study is firstly to investigate the floatability properties of Zilan- Van coal after microwave irradiation and secondly to produce activated carbon from flotation concentrate in order to remove Crystal Violet (CV) from waste water. The flotation experiments showed that microwave heating at 0.9 kW power level for 60 sec exposure time enhanced the hydrophobicity and increased the flotation yield. The activated carbon with remarkable surface area (696 m2/g) was produced from the flotation concentrate and used to adsorb CV from aqueous solution in a batch reactor at different temperature. The adsorption properties of CV onto the activated carbon are discussed in terms of the adsorption isotherms (Langmuir and Freundlich) and found that the experimental results best fitted by the Langmuir model.

  2. Study on the violet LED-induced fluorescence spectra of thioredoxin reductase from human brain

    Institute of Scientific and Technical Information of China (English)

    Xiufeng Lan(兰秀风); Tao Yang(杨涛); Shumei Gao(高淑梅); Xiaosen Luo(骆晓森); Zhonghua Shen(沈中华); Jian Lu(陆建); Xiaowu Ni(倪晓武); Lin Xu(许琳)

    2003-01-01

    The technique of fluorescence spectroscopy is applied to study thioredoxin reductase (TrxR) in the ce;lsof human brain. Experimental results show that, by the violet light emitting diode (LED, λmax=407 nm)light irradiation, TrxR is able to emit three striking spectral bands (528 - 582 nm; 588 - 660 nm; 683 - 700nm). The fluorescence intensity is linear to the concentration of TrxR. The spectrum of denatured TrxR israther different from that of organized TrxR, which reflects the structure change between denatured TrxRand organized TrxR. Furthermore, physical and biochemical mechanisms of fluorescence production forLED light-induced TrxR spectra and its characteristics are analyzed. This paper may be useful to betterunderstand the structure of TrxR, and to provide new spectroscopic information to improve the resolutionfor this kind of biology structure.

  3. Acylated anthocyanins from the blue-violet flowers of Anemone coronaria.

    Science.gov (United States)

    Saito, Norio; Toki, Kenjiro; Moriyama, Hidekazu; Shigihara, Atsushi; Honda, Toshio

    2002-06-01

    Five polyacylated anthocyanins were isolated from blue-violet flowers of Anemone coronaria 'St. Brigid'. They were identified as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its demalonylated form, delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside]-3'-O-[beta-D-glucuronopyranoside], and its cyanidin analog as well as delphinidin 3-O-[2-O-(2-O-(trans-caffeoyl)-beta-D-glucopyranosyl)-6-O-(2-O-(tartaryl)malonyl)-beta-D-galactopyranoside]-7-O-[6-O-(trans-caffeoyl)-beta-D-glucopyranoside].

  4. Decolorization of reactive violet 5 dye in textile wastewater by electrocoagulation

    Directory of Open Access Journals (Sweden)

    Borislav N. Malinovic

    2016-04-01

    Full Text Available The textile dyeing industry consumes large quantities of water and produces large volumes of wastewater from different steps in the dyeing and finishing processes. Wastewater from printing and dyeing units is often rich in color, containing residues of reactive dyes and chemicals, such as complex components. This study investigates the decolorization of synthetic dye wastewater containing textile dye Reactive Violet 5 (RV5 by electrocoagulation. A laboratory batch reactor was used to investigate the effect of various operating parameters using aluminium (Al, iron (Fe and stainless steel (SS anode. The effect of dye concentration, current density, supporting electrolyte, sup­porting electrolyte concentration, electrolysis duration, and material of anode of the systems were evaluated. Color removal efficiency was 22, 91.5 and 99.8 % in 15 minutes using Al, Fe and SS anode, respectively (j = 10 mA/cm2, cNaCl = 0.171 M.

  5. Photodegradation of Acid Violet 7 with AgBr-ZnO under highly alkaline conditions.

    Science.gov (United States)

    Krishnakumar, B; Swaminathan, M

    2012-12-01

    The photocatalytic activity of AgBr-ZnO was investigated for the degradation of Acid Violet 7 (AV 7) in aqueous solution using UV-A light. AgBr-ZnO is found to be more efficient than commercial ZnO and prepared ZnO at pH 12 for the mineralization of AV 7. The effects of operational parameters such as the amount of photocatalyst, dye concentration, initial pH on photo mineralization have been analyzed. Expect oxone, other oxidants decrease the degradation efficiency. Addition of metal ions and anions decrease the degradation efficiency of AgBr-ZnO significantly. The mineralization of AV 7 has also been confirmed by COD measurements. The mechanism of degradation by AgBr-ZnO is proposed to explain its higher activity under UV light. The catalyst is found to be reusable.

  6. Performance and degradation characteristics of blue-violet laser diodes grown by molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Tan, W.S.; Kauer, M.; Hooper, S.E.; Smeeton, T.M.; Bousquet, V.; Rossetti, M.; Heffernan, J. [Sharp Laboratories of Europe Ltd., Edmund Halley Road, Oxford Science Park, Oxford, OX4 4GB (United Kingdom); Xiu, H.; Humphreys, C.J. [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge, CB2 3QZ (United Kingdom)

    2009-06-15

    This paper reports the state of the art performance for blue-violet laser diodes (LD) grown by molecular beam epitaxy. Improvements in device design and growth have resulted in a threshold current density of 3.6 kA/cm{sup 2}, which translates into improved cw lifetime of up to 42 hours. Reducing the internal loss resulted in a high cw slope efficiency of 1.08 W/A and a maximum cw output power of 145 mW. To obtain a better understanding of the LD failure mechanism, degraded LDs were analysed using surface mapping techniques such as photoluminescence and electroluminescence on a micrometric scale, which allows the identification of failure regions. These measurements revealed increased nonradiative recombination in localized regions and increased current injection non-uniformities as possible mechanisms for LD performance degradation after aging. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Insight into biosorption equilibrium, kinetics and thermodynamics of crystal violet onto Ananas comosus (pineapple) leaf powder

    Science.gov (United States)

    Chakraborty, Sagnik; Chowdhury, Shamik; Saha, Papita Das

    2012-06-01

    Biosorption performance of pineapple leaf powder (PLP) for removal of crystal violet (CV) from its aqueous solutions was investigated. To this end, the influence of operational parameters such as pH, biosorbent dose, initial dye concentration and temperature were studied employing a batch experimental setup. The biosorption process followed the Langmuir isotherm model with high correlation coefficients ( R 2 > 0.99) at different temperatures. The maximum monolayer biosorption capacity was found to be 78.22 mg g-1 at 293 K. The kinetic data conformed to the pseudo-second-order kinetic model. The activation energy of the system was calculated as 58.96 kJ mol- 1 , indicating chemisorption nature of the ongoing biosorption process. A thermodynamic study showed spontaneous and exothermic nature of the biosorption process. Owing to its low cost and high dye uptake capacity, PLP has potential for application as biosorbent for removal of CV from aqueous solutions.

  8. Preconcentrafion/separation and determination of mercury using microcrystalline phenolphthalein modified by ethyl violet

    Institute of Scientific and Technical Information of China (English)

    LI Ying; LI Quanrnin; OUYANG Ruizhuo

    2007-01-01

    A novel method was developed for enrichment and separation of trace mercury using phenolphthalein modified by ethyl violet (EV).The effects of different parameters,such as stirring time, various metal ions and salts,and the amounts of phenolphthalein, NH4SCN,and EV on the extraction rate of mercury were studied,to select the experimental conditions.Under optimum conditions,mercury can be adsorbed on the surface of microcrystalline phenolphthalein by the intermolecular action strength.The possible reaction mechanism for the enrichment of mercury was discussed in detail.Hg(Ⅱ)could be completely separated from Fe(Ⅱ),Co(Ⅱ),Ni(Ⅱ),Mn(Ⅱ),Cd(Ⅱ),Cr(Ⅲ), and Al(Ⅲ) in the solution.The proposed method has been successfully applied to the determination of trace mercury in industrial wastewater with the recoveries 1.4%,1.1%,and1.2%,respectively.The analytical results were very satisfactory.

  9. Unpredictable adsorption and visible light induced decolorization of nano rutile for the treatment of crystal violet

    Science.gov (United States)

    Dong, Yanling; Liu, Yang; Lu, Dingze; Zheng, Feng; Fang, Pengfei; Zhang, Haining

    2017-04-01

    Photocatalysts containing different ratios of anatase and rutile are prepared via heat treatment of Degussa P-25 titania. X-ray diffraction (XRD), Bruuauer-Emmett-Teller (BET), ultraviolet-visible light diffuse reflectance spectra (DRS), Raman spectra (Raman), positron annihilation lifetime spectra (PAL) and temperature-programmed desorption (TPD) are applied to investigate the phase composition of the synthesized catalysts. Using crystal violet (CV) as the target pollutant, the unexpected visible light decolorization of rutile is observed. Despite the decreased specific surface area, the as-synthesized rutile samples exhibit much higher adsorption capability of CV than P-25 does, which in turn leads to improved photoreaction efficiency. Since the rutile samples can't absorb the visible light, the degradation under visible light irradiation is attributed to self-sensitization of CV on the surface of rutile.

  10. Controllable Assembly and Spectroscopic Behavior of Brilliant Cresyl Violet in Different Environments

    Science.gov (United States)

    Ma, Q.; Song, J.-P.; Guo, Y.; Shuang, Sh.-M.; Dong, Ch.

    2017-01-01

    In this paper, the aggregation behavior of brilliant cresyl violet (BCV) was studied using UV-vis absorption spectroscopy. BCV aggregation depends not only on the properties of the solvent and electrolyte, and the temperature and concentration of the dye solution, but also on the anionic surfactant. The results demonstrate that Nafion triggers trimer formation. Graphene oxide adjusts the relative position of dye molecules on the template through the electrostatic force and π-π stacking interactions to form highly ordered H-aggregates. However, BCV molecules on the graphene surface form the so-called J-aggregates after removal of the oxygen-containing surface groups by hydrazine reduction. The major driving forces affecting BCV aggregation are the electrostatic force, π-π stacking interactions, and hydrogen-bonding interactions.

  11. Highly solar active Fe(III) immobilised alumina for the degradation of Acid Violet 7

    Energy Technology Data Exchange (ETDEWEB)

    Muthuvel, Inbasekaran; Swaminathan, Meenakshisundaram [Department of Chemistry, Annamalai University, Annamalainagar 608 002 (India)

    2008-08-15

    The hetero-Fenton catalyst Fe(III)-Al{sub 2}O{sub 3} was prepared and characterised by ICP-AES, FT-IR and SEM-EDX. A detailed investigation of photocatalytic degradation of Acid Violet 7 (AV 7) using this Fenton immobilised Al{sub 2}O{sub 3} catalyst was carried out. The optimal reaction conditions for the photodegradation of AV 7 with this catalyst are reported. Higher efficiency of the catalyst in solar light than in UV light makes this heterophoto-Fenton degradation, a green technological process. The catalyst is found to be stable and reusable. The completion of degradation has also been confirmed by chemical oxygen demand (COD) measurements. (author)

  12. Molecularly Imprinted Polymers for Selective Extraction of Crystal Violet from Natural Seawater coupled with High- Performance Liquid Chromatographic Determination

    Institute of Scientific and Technical Information of China (English)

    LIAN Ziru; WANG Jiangtao

    2014-01-01

    Molecularly imprinted polymers (MIPs) were prepared by the bulk polymerization using crystal violet as the template molecule, and the methacrylic acid and ethylene glycol dimetheacrylate as functional monomer and cross-linker, respectively. Sys-tematic investigations of synthetic conditions were conducted. The surface morphology and recognition mechanism of the obtained polymers were studied using scanning electron microscope and spectrophotometric analysis. MIPs showed high affinity to template molecule and were successfully applied as special solid-phase extraction sorbent for selective extraction of crystal violet from natural seawater. An off-line molecularly imprinted solid-phase extraction (MISPE) method followed by high-performance liquid chroma-tography with diodearray detection for the analysis of crystal violet was also established. MISPE columns have good recoveries for crystal violet standard solutions and good linearity was obtained over the concentration range of 0-200μg L-1 (R2>0.99). Finally, two natural seawater samples were investigated. The recoveries of spiked seawater on the MISPE columns were from 44.47% to 62.34%, the relative standard deviation (n=3) being in the range of 2.89%-5.96%.

  13. Sterilization of African Violet in the in Vitro Culture Using Synthesized Silver Nanoparticles by Two Plant Extracts

    Directory of Open Access Journals (Sweden)

    M. Solgi

    2015-12-01

    Full Text Available One of the major advantages of in vitro culture of African violet (Saintpaulha ionantha is production of new cultivars and propagation of their chimera which might not be propagated by the other methods. In this study, we tested the effects of silver nanoparticles on the sterilization rate (antifungal and antibacterial activity, regeneration and shoot formation of African violet "Pink Amiss" explants. These nanoparticles were synthesized from pomegranate peels and Damask rose petals extracts. We used a completely randomized design test with factorial arrangement to investigate various volumetric ratios of plant extracts to silver nitrate (1:20, 1:10, 1:5 and 1:1 on the culture contaminations. Using silver nanoparticles synthesized by the plant extracts, especially Damask rose petals extract resulted in no fungal and bacterial contamination in the African violet explants after 1 and 3 weeks as compared to the control, and silver nitrate (1mM. All tested concentrations of the silver nanoparticles significantly (P &le 0.05 controlled both bacterial and fungal contaminations. The 1:20 ratio of plant extracts to silver nitrate showed the best control. In addition, the highest regeneration (%52 and shoot regeneration (%38 was observed in this treatment. In conclusion, we suggest using silver nanoparticles synthesized by plant extracts for sterilization of in Vitro Culture for African Violet rather than using other chemicals such as silver nitrate.

  14. Violet diode laser-induced chlorophyll fluorescence: a tool for assessing mosaic disease severity in cassava (Manihot esculenta Crantz) cultivars.

    Science.gov (United States)

    Anderson, Benjamin; Eghan, Moses J; Asare-Bediako, Elvis; Buah-Bassuah, Paul K

    2012-01-01

    Violet diode laser-induced chlorophyll fluorescence was used in agronomical assessment (disease severity and average yield per plant). Because cassava (Manihot esculenta Crantz) is of economic importance, improved cultivars with various levels of affinity for cassava mosaic disease were investigated. Fluorescence data correlated with cassava mosaic disease severity levels and with the average yield per plant.

  15. Enhanced violet photoemission of nanocrystalline fluorine doped zinc oxide (FZO) thin films

    Science.gov (United States)

    Anusha, Muthukumar; Arivuoli, D.; Manikandan, E.; Jayachandran, M.

    2015-09-01

    Highly stable fluorine doped nanocrystalline zinc oxide thin films were prepared on corning glass substrates by aerosol assisted chemical vapor deposition (AACVD) at variable deposition temperature of 360 °C, 380 °C and 420 °C. Especially, the optimum deposition temperature was investigated for high intense violet emission. The film crystallinity improved with the increasing deposition temperature and highly textured film was obtained at 420 °C. The films exhibited surface morphology variation from spherical to platelets due to deposition temperature effect, analyzed by field emission scanning electron microscope (FE-SEM). Higher growth rate observed at 420 °C which leads larger grains and lowest resistivity of ∼5.77 Ω cm among the deposited films which may be due to reduction in zinc vacancies and grain boundary area. Zinc vacancies are acts as electron killer centres. UV-visible spectra indicated higher transmittance (83-90%) in the visible region. Red shift of optical absorption edges associated with the increase in particle size consistent well with the XRD results. Reduced E2(high) intensity was observed in Raman spectra, for the film deposited at 380 °C which indicates decreased oxygen incorporation confirmed by PL spectra. Especially, enhanced violet emission observed at 3.06 eV for the films deposited at 380 °C due to electronic transition from the defect level of zinc vacancies to the conduction band, probably attributed to enhanced incorporation of 'F' into 'O' sites associated with increased Zn vacancies and also decreased oxygen incorporation consistent with the electrical and Raman analyses.

  16. Determination of crystal violet in water by direct solid phase spectrophotometry after rotating disk sorptive extraction.

    Science.gov (United States)

    Manzo, Valentina; Navarro, Orielle; Honda, Luis; Sánchez, Karen; Inés Toral, M; Richter, Pablo

    2013-03-15

    The microextraction of crystal violet (CV) from water samples into polydimethylsiloxane (PDMS) using the rotating disk sorptive extraction (RDSE) technique was performed. The extracting device was a small Teflon disk that had an embedded miniature magnetic stirring bar and a PDMS (560 μL) film attached to one side of the disk using double-sided tape. The extraction involves a preconcentration of CV into the PDMS, where the analyte is then directly quantified using solid phase spectrophotometry at 600 nm. Different chemical and extraction device-related variables were studied to achieve the best sensitivity for the determination. The optimum extraction was performed at pH 14 because under this condition, CV is transformed to the neutral and colorless species carbinol, which can be quantitatively transferred to the PDMS phase. Although the colorless species is the chemical form extracted in the PDMS, an intense violet coloration appeared in the phase because the -OH bond in the carbinol molecule is weakened through the formation of hydrogen bonds with the oxygen atoms of the PDMS, allowing the resonance between the three benzene rings to compensate for the charge deficit on the central carbon atom of the molecule. The accuracy and precision of the method were evaluated in river water samples spiked with 10 and 30 μg L(-1) of CV, yielding a relative standard deviation of 6.2% and 8.4% and a recovery of 98.4% and 99.4%, respectively. The method detection limit was 1.8 μg L(-1) and the limit of quantification was 5.4 μg L(-1), which can be decreased if the sample volume is increased.

  17. Ketone production in ultra marathon runners.

    Science.gov (United States)

    Weibel, J; Glonek, T

    2007-12-01

    The aim of this study was to determine the magnitude of ketone production in ultra marathon runners and what affect if any this has on performance. Participants in the Cliff Young Australian Six Day Race (n=31) provided a prerace urine sample and, then, random urine samples throughout the duration of the event, ranging from 4-20 samples each. Based on urinalysis results, participants were divided into two groups: those who formed ketones (ketone group), and those who did not form ketones or formed ketones only once during a race at the lowest recordable value (non-ketone group). The average ketone level of the 22 athletes in the ketone group (value+/-standard deviation: 5.67+/-5.59 mg/dL) was statistically different from 9 athletes who were in the non-ketone group (0.18+/-0.14 mg/dL) (Pketone value was compared, excluding runners who did not complete the race, the ketone group (5.88+/-1.37) remained statistically different from the non-ketone group (0.2+/-0.45) (Pketones and runners who do not make ketones, the level of ketones produced did not affect overall distance run, which is the performance criterion of the race. The nature of this extreme event has illuminated a physiologic difference among ultra marathon runners, and although this difference does not appear to affect race performance, the long-term health consequences are unknown and additional rigorous research is warranted.

  18. Legacy to the extreme

    NARCIS (Netherlands)

    A. van Deursen (Arie); T. Kuipers (Tobias); L.M.F. Moonen (Leon)

    2000-01-01

    textabstractWe explore the differences between developing a system using extreme programming techniques, and maintaining a legacy system. We investigate whether applying extreme programming techniques to legacy maintenance is useful and feasible.

  19. Legacy to the extreme

    NARCIS (Netherlands)

    Deursen, A. van; Kuipers, T.; Moonen, L.M.F.

    2000-01-01

    We explore the differences between developing a system using extreme programming techniques, and maintaining a legacy system. We investigate whether applying extreme programming techniques to legacy maintenance is useful and feasible.

  20. Extreme environment electronics

    CERN Document Server

    Cressler, John D

    2012-01-01

    Unfriendly to conventional electronic devices, circuits, and systems, extreme environments represent a serious challenge to designers and mission architects. The first truly comprehensive guide to this specialized field, Extreme Environment Electronics explains the essential aspects of designing and using devices, circuits, and electronic systems intended to operate in extreme environments, including across wide temperature ranges and in radiation-intense scenarios such as space. The Definitive Guide to Extreme Environment Electronics Featuring contributions by some of the world's foremost exp

  1. A very luminous magnetar-powered supernova associated with an ultra-long gamma-ray burst

    CERN Document Server

    Greiner, Jochen; Kann, D Alexander; Krühler, Thomas; Pian, Elena; Prentice, Simon; E., Felipe Olivares; Rossi, Andrea; Klose, Sylvio; Taubenberger, Stefan; Knust, Fabian; Afonso, Paulo M J; Ashall, Chris; Bolmer, Jan; Delvaux, Corentin; Diehl, Roland; Elliott, Jonathan; Filgas, Robert; Fynbo, Johan P U; Graham, John F; Guelbenzu, Ana Nicuesa; Kobayashi, Shiho; Leloudas, Giorgos; Savaglio, Sandra; Schady, Patricia; Schmid, Sebastian; Schweyer, Tassilo; Sudilovsky, Vladimir; Tanga, Mohit; Updike, Adria C; van Eerten, Hendrik; Varela, Karla

    2015-01-01

    A new class of ultra-long duration (>10,000 s) gamma-ray bursts has recently been suggested. They may originate in the explosion of stars with much larger radii than normal long gamma-ray bursts or in the tidal disruptions of a star. No clear supernova had yet been associated with an ultra-long gamma-ray burst. Here we report that a supernova (2011kl) was associated with the ultra-long duration burst 111209A, at z=0.677. This supernova is more than 3 times more luminous than type Ic supernovae associated with long gamma-ray bursts, and its spectrum is distinctly different. The continuum slope resembles those of super-luminous supernovae, but extends farther down into the rest-frame ultra-violet implying a low metal content. The light curve evolves much more rapidly than super-luminous supernovae. The combination of high luminosity and low metal-line opacity cannot be reconciled with typical type Ic supernovae, but can be reproduced by a model where extra energy is injected by a strongly magnetized neutron sta...

  2. Deficiently Extremal Gorenstein Algebras

    Indian Academy of Sciences (India)

    Pavinder Singh

    2011-08-01

    The aim of this article is to study the homological properties of deficiently extremal Gorenstein algebras. We prove that if / is an odd deficiently extremal Gorenstein algebra with pure minimal free resolution, then the codimension of / must be odd. As an application, the structure of pure minimal free resolution of a nearly extremal Gorenstein algebra is obtained.

  3. Extreme value distributions

    CERN Document Server

    Ahsanullah, Mohammad

    2016-01-01

    The aim of the book is to give a through account of the basic theory of extreme value distributions. The book cover a wide range of materials available to date. The central ideas and results of extreme value distributions are presented. The book rwill be useful o applied statisticians as well statisticians interrested to work in the area of extreme value distributions.vmonograph presents the central ideas and results of extreme value distributions.The monograph gives self-contained of theory and applications of extreme value distributions.

  4. Endoscopic diagnosis of invasion depth for early colorectal carcinomas: a prospective comparative study of narrow-band imaging, acetic acid, and crystal violet.

    Science.gov (United States)

    Zhang, Jing-Jing; Gu, Li-Yang; Chen, Xiao-Yu; Gao, Yun-Jie; Ge, Zhi-Zheng; Li, Xiao-Bo

    2015-02-01

    Several studies have validated the effectiveness of narrow-band imaging (NBI) in estimating invasion depth of early colorectal cancers. However, comparative diagnostic accuracy between NBI and chromoendoscopy remains unclear. Other than crystal violet, use of acetic acid as a new staining method to diagnose deep submucosal invasive (SM-d) carcinomas has not been extensively evaluated. We aimed to assess the diagnostic accuracy and interobserver agreement of NBI, acetic acid enhancement, and crystal violet staining in predicting invasion depth of early colorectal cancers. A total of 112 early colorectal cancers were prospectively observed by NBI, acetic acid, and crystal violet staining in sequence by 1 expert colonoscopist. All endoscopic images of each technique were stored and reassessed. Finally, 294 images of 98 lesions were selected for evaluation by 3 less experienced endoscopists. The accuracy of NBI, acetic acid, and crystal violet for real-time diagnosis was 85.7%, 86.6%, and 92.9%, respectively. For image evaluation by novices, NBI achieved the highest accuracy of 80.6%, compared with that of 72.4% by acetic acid, and 75.8% by crystal violet. The kappa values of NBI, acetic acid, and crystal violet among the 3 trainees were 0.74 (95% CI 0.65-0.83), 0.68 (95% CI 0.59-0.77), and 0.70 (95% CI 0.61-0.79), respectively. For diagnosis of SM-d carcinoma, NBI was slightly inferior to crystal violet staining, when performed by the expert endoscopist. However, NBI yielded higher accuracy than crystal violet staining, in terms of less experienced endoscopists. Acetic acid enhancement with pit pattern analysis was capable of predicting SM-d carcinoma, comparable to the traditional crystal violet staining.

  5. Ultra High Energy Nuclei Propagation

    CERN Document Server

    Aloisio, Roberto

    2008-01-01

    We discuss the problem of ultra high energy nuclei propagation in astrophysical backgrounds. We present a new analytical computation scheme based on the hypothesis of continuos energy losses in a kinetic formulation of the particles propagation. This scheme enables the computation of the fluxes of ultra high energy nuclei as well as the fluxes of secondaries (nuclei and nucleons) produced by the process of photo-disintegration suffered by nuclei.

  6. CFT Duals for Ultra-Spinning Gauged Supergravity Black Holes

    CERN Document Server

    Noorbakhsh, S M

    2016-01-01

    Recently a new class of asymptotically AdS ultra-spinning black holes has been constructed with non-compact horizon of finite area [1], in which the asymptotic rotation is effectively boosted to the speed of light. We employ this technique to the $4$-dimensional $U(1)^4$ and $5$-dimensional $U(1)^3$ gauged supergravity black holes. The obtained new exact black hole solutions for both cases possess a non-compact horizon; their topologies are sphere with two punctures. We then demonstrate that the ultra-spinning limit commutes with the extremality condition as well as the near horizon limit for both black holes. We also show that the near horizon extremal geometries of the resulting ultra-spinning gauged supergravity black holes lead to the well-known result which contains an AdS$_2$ throat. We then obtain the $[(d-1)/2]$ central charges of the dual CFTs. By assuming the Cardy formula, we show that despite the non-compactness of the horizon, microscopic entropy of the dual CFT is precisely equivalent to the Bek...

  7. Driving Extreme Efficiency to Market

    Science.gov (United States)

    Garbesi, Karina

    2014-03-01

    The rapid development of extremely energy efficient appliances and equipment is essential to curtail catastrophic climate disruption. This will require the on-going development of products that apply all best-practices and that take advantage of the synergies of hybridization and building integration. Beyond that, it requires the development of new disruptive technologies and concepts. To facilitate these goals, in 2011 the Lawrence Berkeley National Laboratory and the U.S. Department of Energy launched the Max Tech and Beyond Design Competition for Ultra-Low-Energy-Use Appliances and Equipment. Now in its third year, the competition supports faculty-lead student design teams at U.S. universities to develop and test new technology prototypes. This talk describes what the competition and the Max Tech Program are doing to drive such rapid technology progress and to facilitate the entry to the market of successful Max Tech prototypes. The talk also initiates a discussion of physicists' unique role in driving that technology progress faster and farther. Emerging Technologies, Building Technologies Office, U.S. Department of Energy.

  8. Measuring the Photocatalytic Breakdown of Crystal Violet Dye using a Light Emitting Diode Approach

    Science.gov (United States)

    Ryan, Robert E.; Underwood, Lauren W.; O'Neal, Duane; Pagnutti, Mary; Davis, Bruce A.

    2009-01-01

    A simple method to estimate the photocatalytic reactivity performance of spray-on titanium dioxide coatings for transmissive glass surfaces was developed. This novel technique provides a standardized method to evaluate the efficiency of photocatalytic material systems over a variety of illumination levels. To date, photocatalysis assessments have generally been conducted using mercury black light lamps. Illumination levels for these types of lamps are difficult to vary, consequently limiting their use for assessing material performance under a diverse range of simulated environmental conditions. This new technique uses an ultraviolet (UV) gallium nitride (GaN) light emitting diode (LED) array instead of a traditional black light to initiate and sustain photocatalytic breakdown. This method was tested with a UV-resistant dye (crystal violet) applied to a titanium dioxide coated glass slide. Experimental control is accomplished by applying crystal violet to both titanium dioxide coated slides and uncoated control slides. A slide is illuminated by the UV LED array, at various light levels representative of outdoor and indoor conditions, from the dye side of the slide. To monitor degradation of the dye over time, a temperature-stabilized white light LED, whose emission spectrum overlaps with the dye absorption spectrum, is used to illuminate the opposite side of the slide. Using a spectrometer, the amount of light from the white light LED transmitted through the slide as the dye degrades is monitored as a function of wavelength and time and is subsequently analyzed. In this way, the rate of degradation for photocatalytically coated versus uncoated slide surfaces can be compared. Results demonstrate that the dye absorption decreased much more rapidly on the photocatalytically coated slides than on the control uncoated slides, and that dye degradation is dependent on illumination level. For photocatalytic activity assessment purposes, this experimental configuration and

  9. ULTRA-HIGH ENERGY COSMIC RAY AND NEUTRINO DETECTION USING THE MOON : FIRST RESULTS

    NARCIS (Netherlands)

    Scholten, O.; Bacelar, J.; Singh, K.; Al Yahyaoui, R.; Buitink, S.; Falcke, H.; Braun, R.; de Bruyn, A. G.; Strom, R. G.; Stappers, B.

    2009-01-01

    We show that at wavelengths comparable to the length of the shower produced by an Ultra-High Energy cosmic ray or neutrino, radio signals are an extremely efficient way to detect these particles. First results are presented of an analysis of 20 hours of observation data for NuMoon project using the

  10. Lunar detection of ultra-high-energy cosmic rays and neutrinos

    NARCIS (Netherlands)

    Bray, J. D.; Alvarez-Muñiz, J.; Buitink, S.; Dagkesamanskii, R. D.; Ekers, R. D.; Falcke, H.; Gayley, K. G.; Huege, T.; James, C. W.; Mevius, M.; Mutel, R. L.; Protheroe, R. J.; Scholten, O.; Spencer, R. E.; ter Veen, S.

    2014-01-01

    The origin of the most energetic particles in nature, the ultra-high-energy (UHE) cosmic rays, is still a mystery. Due to their extremely low flux, even the 3,000 km^2 Pierre Auger detector registers only about 30 cosmic rays per year with sufficiently high energy to be used for directional studies.

  11. [Sports and extreme conditions. Cardiovascular incidence in long term exertion and extreme temperatures (heat, cold)].

    Science.gov (United States)

    Melin, B; Savourey, G

    2001-06-30

    During ultra-endurance exercise, both increase in body temperature and dehydration due to sweat losses, lead to a decrease in central blood volume. The heart rate drift allows maintaining appropriate cardiac output, in order to satisfy both muscle perfusion and heat transfer requirements by increasing skin blood flow. The resulting dehydration can impair thermal regulation and increase the risks of serious accidents as heat stroke. Endurance events, lasting more than 8 hours, result in large sweat sodium chloride losses. Thus, ingestion of large amounts of water with poor salt intake can induce symptomatic hyponatremia (plasma sodium extreme condition.

  12. Use of hydrogen peroxide treatment and crystal violet agar plates for selective recovery of bacteriophages from natural environments

    Energy Technology Data Exchange (ETDEWEB)

    Asghari, A.; Farrah, S.R.; Bitton, G. (Univ. of Florida, Gainesville (United States))

    1992-04-01

    Hydrogen peroxide inactivated bacteriophages and bacteria at different rates. A concentration of 0.1% hydrogen peroxide reduced the numbers of several bacteria by an average of 94% but caused an average of 25% inactivation in the numbers of bacteriophages tested. Treating natural samples with hydrogen peroxide selectively reduced the indigenous bacterial flora and permitted better visualization of plaques of lawns of Escherichia coli C-3000. In some cases indigenous gram-positive bacteria were relatively resistant to hydrogen peroxide, but their growth could be limited by incorporation of crystal violet into the bottom agar used for plaque assays. The use of hydrogen peroxide treatment and crystal violet-containing plates permitted recovery of more phages from natural samples than did other procedures, such as chloroform pretreatment or the use of selective plating agar such as EC medium.

  13. Bioremoval of Basic Violet 3 and Acid Blue 93 by Pseudomonas putida and its adsorption isotherms and kinetics.

    Science.gov (United States)

    Arunarani, A; Chandran, Preethy; Ranganathan, B V; Vasanthi, N S; Sudheer Khan, S

    2013-02-01

    Basic Violet 3 and Acid Blue 93 are the most important group of synthetic colourants extensively used in textile industries for dyeing cotton, wool, silk and nylon. Release of these dye pollutants in to the environment adversely affects the human health and aquatic organisms. The present study we used Pseudomonas putida MTCC 4910 for the adsorptive removal of Basic Violet 3 and Acid Blue 93 from the aqueous solutions. The pH (4-9) and NaCl concentrations (1mM-1M) did not influence the adsorption process. The equilibrium adsorption process fitted well to Freundlich model than Langmuir model. The kinetics of adsorption fitted well by pseudo-second-order. Thus in the present study an attempt has been made to exploit the dye removal capability of P. putida MTCC 4910, and it was found to be an efficient microbe that could be used for bio removal of dyes from textile effluents.

  14. Ecological aspects of the extreme purification of water

    Science.gov (United States)

    Shaposhnik, Vladimir A.; Mazo, A. A.; Frölich, P.

    1991-11-01

    The influence on the eco-system of the products of the large-scale technology for the preparation of ultra-pure water required for the electronic and radiotechnical industries is examined. The distillation, ion-exchange, and membrane methods are subjected to a comparative analysis. It is shown that the membrane method for the extreme purification of water is ecologically the most desirable. The methods for the elimination of nitrates from drinking water are examined. The bibliography includes 41 references.

  15. Extreme Velocity Wind Sensor

    Science.gov (United States)

    Perotti, Jose; Voska, Ned (Technical Monitor)

    2002-01-01

    This presentation provides an overview of the development of new hurricane wind sensor (Extreme Velocity Wind Sensor) for the Kennedy Space Center (KSC) which is designed to withstand winds of up to three hundred miles an hour. The proposed Extreme Velocity Wind Sensor contains no moveable components that would be exposed to extreme wind conditions. Topics covered include: need for new hurricane wind sensor, conceptual design, software applications, computational fluid dynamic simulations of design concept, preliminary performance tests, and project status.

  16. Chemical analysis of rutile - a pyrocatechol violet spectrophotometric procedure for the direct microdetermination of zirconium

    Science.gov (United States)

    Meyrowitz, Robert

    1973-01-01

    The ZrO2 content of rutile is determined spectrophotometrically by a direct pyrocatechol violet procedure. The sample is decomposed by potassium pyrosulfate fusion in a transparent quartz crucible, and a sulfuric acid solution of the melt is used for the determination at a pH of 5.1. Of the elements commonly present in rutile, only titanium and niobium occur in concentrations large enough to interfere. Titanium and niobium interference is overcome by adding the titanium and niobium contents of the sample to the standard zirconium solutions used for the standard zirconium curve. The absorbance is measured at 570 nm. Beer's law is obeyed within the range of 0.05-1.50 ppm ZrO2. In the presence of 50 ppm TiO2, the range is 0.15-1.50 ppm ZrO2 . The tolerances of 47 elements were determined. The sensitivity is 0.0058 ug Zr/cm2 . The variables in the method were studied, and typical results are given for commercial rutile concentrates.

  17. Kinetic and Thermodynamic Studies of the Adsorption of Crystal Violet onto Used Black Tea Leaves

    Directory of Open Access Journals (Sweden)

    Mohammad Abul Hossain

    2013-11-01

    Full Text Available This study presents the kinetic and thermodynamic investigation of the adsorption of crystal violet (CV on used black tea leaves (UBTL from aqueous solution to evaluate the feasibility of the process. The effects of concentration, solution pH and temperature on adsorption kinetics were carried out in batch process. Kinetic studies have shown that the adsorption data partially follow simple first order, second order and pseudo second order kinetic equations for different initial concentrations at pH 2.0. The equilibrium amount adsorbed, equilibrium concentration and rate constant were calculated from better fitted pseudo second order kinetic plots for different initial concentrations. The equilibrium amount adsorbed (200 mg/g at 30 oC increased with the increase of temperature, indicated endothermic nature of the adsorption. The apparent activation energy of adsorption was determined from Arrhenius plot using pseudo second order rate constant and the value, Ea = 83.1 kJ/mol, revealed the process is chemisorption. Thermodynamic parameters: DHo, DGo and DSo, were determined from the equilibrium adsorption constant and the results obtained confirmed that the adsorption process was feasible, less spontaneous and endothermic. The equilibrium amount adsorbed was found to be increased with increase of solution pH from 2.0 to 6.0 indicating electrostatic interaction between cationic CV with anionic surface of UBTL dominated at higher pH due to the low zero point charge of pH of UBTL.

  18. Bacillus amyloliquefaciens biofilm as a novel biosorbent for the removal of crystal violet from solution.

    Science.gov (United States)

    Sun, Pengfei; Hui, Cai; Wang, Sheng; Wan, Li; Zhang, Xin; Zhao, Yuhua

    2016-03-01

    Bacillus amyloliquefaciens biofilm shows promise for use in the control of soil-borne pathogens; however, it has never been used to treat dye-polluted wastewaters. Here, we propose the novel idea of using B. amyloliquefaciens biofilm for the adsorption of crystal violet (CV) from liquids. The relative contents of three main elements (C1s, O1s, and N1s) in the biofilm were 65.55%, 21.21%, and 13.24%, respectively. The results of Fourier transform infrared (FTIR) spectra and X-ray photoelectron spectroscopy revealed that the biofilm contained β-type heteropolysaccharide and proteins. The ruggedness of the biofilm surface due to embedded bacterial cells suggested potential adsorption sites for CV molecules. The maximum capacity for CV adsorption was 582.41mg/g, which is the largest value reported to date for any CV adsorbent. Blueshift occurred in the FTIR spectrum of CV-loaded biofilm as compared to that of virgin biofilm, confirming a physical adsorption process. We found that CV adsorption by biofilm was complex and resulted from intraparticle diffusion as well as surface adsorption. Our data also suggested that the process is exothermal and spontaneous, with micropore diffusion as the rate-limiting step. These findings provide a basis for using B. amyloliquefaciens biofilm as an efficient adsorbent for treating CV-polluted wastewaters.

  19. [Flotation spectrophotometric determination of copper on isochromatic dye ion pair with crystal violet and bromopnenol blue].

    Science.gov (United States)

    Liu, B; Chen, C; Zuo, B

    1999-02-01

    Bromophenol blue (BPB) was produced and entered into the aqueous phase when NaOH solution of pH = 10 was added to Cu(biq)2BPB by trichloromethane and isoamyl alcohol (20:1) extractive. And then CV x BPB was floated by crystal violet (CV) with benzene solution. The flotation was dissolved in ethanol and the absorbance of the solution measured at 590 nm. The sensitivity was raised because of the two dyes assistant effect. The molar absorptivity was 1.45 x 10(5) L x mol(-1) x cm(-1). Copper in the sample was separated first by extracting the Cu(biq)2BPB complex with trichloromethane and isoamyl alcohol, thus achieving a high selectivity. Beer's law was obeyd in the range of 0-0. 4 mg/L with a relative standard deviation of 3.6%. For 4.8 x 10(-8) g/mL copper solution, the recoveries were 97.8%-101.7%.

  20. Laccase-conjugated amino-functionalized nanosilica for efficient degradation of Reactive Violet 1 dye

    Science.gov (United States)

    Gahlout, Mayur; Rudakiya, Darshan M.; Gupte, Shilpa; Gupte, Akshaya

    2017-08-01

    Immobilization of enzyme with nanostructures enhances its ideal characteristics, which may allow the enzyme to become more stable and resistant. The present investigation deals with the formulation of laccase nanosilica conjugates to overcome the problems associated with its stability and reusability. Synthesized nanosilica and laccase nanoparticles were spherical shaped, with the mean size of 220 and 615 nm, respectively. Laccase nanoparticles had an optimum temperature of 55 °C and pH 4.0 for the oxidation of ABTS. Laccase nanoparticle retained 79% of residual activity till 20th cycle. It also showed 91% of its initial activity at lower temperatures even after 60 days. Laccase nanoparticles were applied for Reactive Violet 1 degradation wherein 96.76% of decolourization was obtained at pH 5.0 and 30 °C within 12 h. Toxicity studies on microbes and plants suggested that the degraded metabolites were less toxic than control dye. Thus, the method applied for immobilization increased storage stability and reusability of laccase, and therefore, it can be utilized for efficient degradation of azo dyes.

  1. The complete mitochondrial genome of the Violet-spotted reef lobster Enoplometopus debelius (Crustacea, Astacidea, Enoplometopidae).

    Science.gov (United States)

    Ahn, Dong-Ha; Min, Gi-Sik; Park, Joong-Ki; Kim, Sanghee

    2016-05-01

    The violet-spotted reef lobster Enoplometopus debelius Holthuis, 1983 (Decapoda, Astacidea, Enoplometopidae) is found in the tropical reef areas of the Indo-Pacific region, and is a highly prized and very popular species in the aquarium trade industry. The complete mitochondrial genome of E. debelius has 15,641 base pairs consisting of 13 protein-coding genes, 22 transfer RNAs, 2 ribosomal RNAs, and a control region of 746 bp. The base composition of E. debelius is 36.4% A, 35.3% T, 18.1% C, 10.3% G, and the species has an AT content of 71.7%. The E. debelius mitogenome was found to have a gene arrangement and transcriptional polarity identical to that of the Homarus americanus mitogenome, a representative of the arthropod ground pattern. Here, we present the complete mitogenome sequence of E. debelius, which is the first in the superfamily Enoplometopoidea. These data will provide a useful molecular resource for the phylogenetic study of the infraorder Astacidea/order Decapoda.

  2. Application potential of grapefruit peel as dye sorbent: Kinetics, equilibrium and mechanism of crystal violet adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Saeed, Asma, E-mail: asmadr@wol.net.pk [Environmental Biotechnology Group, Biotechnology and Food Research Centre, PCSIR Laboratories Complex, Ferozepur Road, Lahore 54600 (Pakistan); Sharif, Mehwish [School of Biological Sciences, University of the Punjab, Lahore 54590 (Pakistan); Iqbal, Muhammad [Environmental Biotechnology Group, Biotechnology and Food Research Centre, PCSIR Laboratories Complex, Ferozepur Road, Lahore 54600 (Pakistan)

    2010-07-15

    This study reports the sorption of crystal violet (CV) dye by grapefruit peel (GFP), which has application potential in the remediation of dye-contaminated wastewaters using a solid waste generated by the citrus fruit juice industry. Batch adsorption of CV was conducted to evaluate the effect of initial pH, contact time, temperature, initial dye concentration, GFP adsorbent dose, and removal of the adsorbate CV dye from aqueous solution to understand the mechanism of sorption involved. Sorption equilibrium reached rapidly with 96% CV removal in 60 min. Fit of the sorption experimental data was tested on the pseudo-first and pseudo-second-order kinetics mathematical equations, which was noted to follow the pseudo-second-order kinetics better, with coefficient of correlation {>=}0.992. The equilibrium process was well described by the Langmuir isotherm model, with maximum sorption capacity of 254.16 mg g{sup -1}. The GFP was regenerated using 1 M NaOH, with up to 98.25% recovery of CV and could be reused as a dye sorbent in repeated cycles. GFP was also shown to be highly effective in removing CV from aqueous solution in continuous-flow fixed-bed column reactors. The study shows that GFP has the potential of application as an efficient sorbent for the removal of CV from aqueous solutions.

  3. Blue-violet photoluminescence of 4-isopropyl-pyridine hydroxide crystals.

    Science.gov (United States)

    Vaganova, Evgenia; Wachtel, Ellen; Leitus, Gregory; Danovich, David; Popov, Inna; Dubnikova, Faina; Yitzchaik, Shlomo

    2014-05-01

    There is continuing interest in determining essential structural features of polymer gels, which display photoelectric and/or thermoelectric behavior. One such gel is the blend, poly(4-vinylpyridine-co-butyl methacrylate)/poly(4-vinylpyridine), dissolved in liquid pyridine. Following extended aeration of a three-component mixture, which serves as a model for the gel side chain interactions, crystallization of a new molecule, 4-isopropylpyridine hydroxide (IPPOH), occurs. X-ray diffraction, DFT modeling, and spectroscopy were used to determine the structural, electronic, and luminescent properties of the crystal. The crystal structure reveals molecules forming head-to-tail, hydrogen-bonded chains without base stacking or marked interchain interaction. The molecular chains are characterized by moderately long-lived, blue-violet luminescence excited in the near-UV. Because these photoluminescent properties resemble those of the gel from which the crystals are derived, we may posit similar structural features in the gel for which direct structural analysis is not available.

  4. Adsorption of crystal violet with diatomite earth&carbon by a modification of hydrothermal carbonization process.

    Science.gov (United States)

    Zhang, Yanzhuo; Li, Jun; Chen, Guanghui; Bian, Wei; Lu, Yun; Li, Wenjing; Zheng, Zhaoming; Cheng, Xiaojie

    2016-01-01

    The high colority and difficulty of decolorization are the most important tasks on printing and dyeing wastewater. This study investigates the ability of diatomite earth&carbon (DE&C) as an adsorbent to removal crystal violet (CV) from aqueous solutions. Fourier transform infrared spectroscopy results indicate the importance of functional groups during the adsorption of CV. The obtained N2 adsorption-desorption isotherm values accord with well IUPAC type II. Our calculations determined a surface area of 73.15 m(2) g(-1) for DE&C and an average pore diameter of 10.56 nm. Equilibrium data of the adsorption process fitted very well to the Langmuir model (R(2) > 0.99). The results of kinetics study showed that the pseudo-second-order model fitted to the experimental data well. The thermodynamic parameters were also evaluated. ΔH° 0 and ΔG° < 0 demonstrated that the adsorption process was spontaneous and exothermic for dye. Furthermore the positive value of ΔS° reflected good affinity of the CV dye.

  5. Characteristics of InGaN multiple quantum well blue-violet laser diodes

    Institute of Scientific and Technical Information of China (English)

    LI Deyao; YANG Hui; LIANG Junwu; ZHANG Shuming; WANG Jianfeng; CHEN Jun; CHEN Lianghui; CHONG Ming; ZHU Jianjun; ZHAO Degang; LIU Zongshun

    2006-01-01

    Studies on InGaN multiple quantum well blue-violet laser diodes have been reported. Laser structures with long-period multiple quantum wells were grown by metal-organic chemical vapor deposition. Triple-axis X-ray diffraction (TAXRD) measurements show that the multiple quantum wells were high quality. Ridge waveguide laser diodes were fabricated with cleaved facet mirrors. The laser diodes lase at room temperature under a pulsed current. A threshold current density of 3.3 kA/cm2 and a characteristic temperature T0 of 145 K were observed for the laser diode.orted. Laser structures with long-period multiple quantum wells were grown by metal-organic chemical vapor deposition. Triple-axis X-ray diffraction (TAXRD) measurements show that the multiple quantum wells were high quality. Ridge waveguide laser diodes were fabricated with cleaved facet mirrors. The laser diodes lase at room temperature under a pulsed current. A threshold current density of 3.3 kA/cm2 and a characteristic temperature T0 of 145 K were observed for the laser diode.

  6. Adsorption of Crystal Violet Dye from Aqueous Solution onto Zeolites from Coal Fly and Bottom Ashes

    Directory of Open Access Journals (Sweden)

    Tharcila Colachite Rodrigues Bertolini

    2013-11-01

    Full Text Available The adsorption of the cationic dye Crystal Violet (CV over zeolites from coal fly ash (ZFA and bottom ash (ZBA was evaluated. The coal fly ash (CFA and the coal bottom ash (CBA used in the synthesis of the zeolites by alkaline hydrothermal treatment were collected in Jorge Lacerda coal-fired power plant located at Capivari de Baixo County, in Santa Catarina State, Brazil. The zeolitic materials were characterized predominantly as hydroxy-sodalite and X. The dye adsorption equilibrium was reached after 10 min for ZFA and ZBA. The kinetics studies indicated that the adsorption followed the pseudo-second order kinetics and that surface adsorption and intraparticle diffusion were involved in the adsorption mechanism for both the adsorbents. The equilibrium data of ZFA was found to best fit to the Langmuir model, while ZBA was best explained by the Freundlich model. The maximum adsorption capacities were 19.6 mg g-1 for the CV/ZFA and 17.6 mg g-1 for the CV/ZBA.

  7. Biodegradation of Basic Violet 3 by Candida krusei isolated from textile wastewater.

    Science.gov (United States)

    Deivasigamani, Charumathi; Das, Nilanjana

    2011-11-01

    Basic Violet 3 (BV) belongs to the most important group of synthetic colorants and is used extensively in textile industries. It is considered as xenobiotic compound which is recalcitrant to biodegradation. As Candida krusei could not use BV as sole carbon source, experiments were conducted to study the effect of cosubstrates on decolorization of BV in semi synthetic medium using glucose, sucrose, lactose, maltose, yeast extract, peptone, urea and ammonium sulphate. Maximum decolorization (74%) was observed in media supplemented with sucrose. Use of sugarcane bagasse extract as sole nutrient source showed 100% decolorization of BV within 24 h under optimized condition. UV-visible, FTIR spectral analysis and HPLC analysis confirmed the biodegradation of BV. Six degradation products were isolated and identified. We propose the biodegradation pathway for BV which occurs via stepwise reduction and demethylation process to yield mono-, di-, tri-, tetra-, penta- and hexa-demethylated BV species which was degraded completely. The study of the enzymes responsible for decolorization showed the activities of lignin peroxidase, lacasse, tyrosinase, NADH-DCIP reductase, MG reductase and azoreductase in cells before and after decolorization. A significant increase in activities of NADH-DCIP reductase and laccase was observed in the cells after decolorization. The yeast C. krusei could show the ability to decolorize the textile dye BV using inexpensive source like sugarcane bagasse extract for decolorization.

  8. Genotoxic and antibutyrylcholinesterasic activities of acid violet 7 and its biodegradation products.

    Science.gov (United States)

    Mansour, Hedi Ben; Mosrati, Ridha; Limem, Ilef; Corroler, David; Ghedira, Kamel; Barillier, Daniel; Chekir-Ghedira, Leila

    2009-01-01

    Acid violet 7, a sulfonated azo dye was degraded by Pseudomonas putida mt-2 in mineral medium at concentrations up to 200 mg/L. The genotoxicity of AV7 and its biodegradation extracts was evaluated by using the DNA-strand scission assay. No genotoxicity was observed, even with or without exposition to UV irradiation, for biodegradation under shaking conditions, but increased significantly after biodegradation under static conditions. In addition, the ability of tested compounds to reduce human plasma butyrylcholinesterase (BuChE) activity was evaluated in vitro. Genotoxicity and anti-BuChE activity generated by the azoreduction products [4'-aminoacetanilid (4'-AA) and 5-acetamido-2-amino-1-hydroxy-3,6-naphtalene disulfonic acid (5-ANDS)] were assessed and compared with that of the parent unsubstituted amines. 4'-AA exhibited a strong genotoxicity, which was imputed to the presence of the acetoxy (COCH3) substituent on the aromatic amine; however, the presence of sulphonic groups in 5-ANDS seems to be responsible for its BuChE inhibition activity. The present study demonstrates that P. putida mt-2, incubated under aerobic conditions, has a catabolism that enables it to degrade AV7 and, especially, to detoxify the dye mixtures.

  9. Removal of Crystal Violet Dye from Aqueous Solutions onto Date Palm Fiber by Adsorption Technique

    Directory of Open Access Journals (Sweden)

    Mashael Alshabanat

    2013-01-01

    Full Text Available The adsorption of crystal violet (CV onto date palm fibers (DPFs was examined in aqueous solution at 25°C. The experimental maximum adsorption capacity value was 0.66×10−6. Langmuir, Freundlich, Elovich and Temkin models were applied to describe the equilibrium isotherms. The influence of pH and temperature on dye removal was evaluated. The percentage removal of CV dye by adsorption onto DPF at different pH and temperatures showed that these factors play a role in the adsorption process. Thermodynamic analysis was performed, and the Gibbs free energy ΔGο, enthalpy change ΔHο, and entropy ΔSο were calculated. The negative values of ΔGο indicate spontaneous adsorption. The negative value of ΔHο indicates that the interaction between CV and DPF is exothermic, and the positive value of ΔSο indicates good affinity between DPF and CV. The kinetic data were fitted to a pseudo-second-order model.

  10. Molecular and structural characterization of some violet phosphate pigments for their non-invasive identification in modern paintings

    Science.gov (United States)

    Anselmi, C.; Vagnini, M.; Cartechini, L.; Grazia, C.; Vivani, R.; Romani, A.; Rosi, F.; Sgamellotti, A.; Miliani, C.

    2017-02-01

    A complete non-invasive characterization by XRF, XRD, near-FTIR and UV-Vis reflectance spectroscopy has been performed on some commercially available violet pigments as well as on pure violet Co-salts also known to be used as pigments. The obtained results show that, after a preliminary elemental characterization, the studied pigments can be easily identified by near-FTIR and UV-Vis spectroscopies since they exhibit peculiar spectral bands in these regions. Among the analyzed samples emerged that the pigment 45350 - "Manganviolett" from Kremer consists of two α- and β-NH4MnP2O7 polymorphs, being α-NH4MnP2O7 the most abundant one; furthermore we found that the pigment R1215D -"Cobalt violet" by Winsor & Newton (no longer available since 2006) displays spectral features that match exactly those of 45820-"Kobaltviolett hell" from Kremer and both are composed by cobalt ammonium phosphate hydrate. Such non-invasive study allowed for the identification of "Manganese Violet" (α-NH4MnP2O7) and anhydrous cobalt phosphate (Co3(PO4)2) on some Boccioni's paintings during MOLAB in situ measurements at the Museo del Novecento (Milano). The spectrum of sample 6 shows, as expected, the O-P-O bending and P-O stretching vibrational multiple bands in the ranges of 420-700 cm-1 and 1000-1250 cm-1, while the peaks located at 760 and 912 cm-1 are attributed to the symmetric and antisymmetric P-O-P vibrations that are typical of the pyrophosphate group. [4]. Characteristic stretching and bending absorptions of the NH4+ cation are visible in the range 3300-3000 cm-1, and at about 1450-1400 cm-1. Typical spectral features of kaolin are visible at 3620 and 3694 cm-1[5].

  11. How extreme is extreme hourly precipitation?

    Science.gov (United States)

    Papalexiou, Simon Michael; Dialynas, Yannis G.; Pappas, Christoforos

    2016-04-01

    The importance of accurate representation of precipitation at fine time scales (e.g., hourly), directly associated with flash flood events, is crucial in hydrological design and prediction. The upper part of a probability distribution, known as the distribution tail, determines the behavior of extreme events. In general, and loosely speaking, tails can be categorized in two families: the subexponential and the hyperexponential family, with the first generating more intense and more frequent extremes compared to the latter. In past studies, the focus has been mainly on daily precipitation, with the Gamma distribution being the most popular model. Here, we investigate the behaviour of tails of hourly precipitation by comparing the upper part of empirical distributions of thousands of records with three general types of tails corresponding to the Pareto, Lognormal, and Weibull distributions. Specifically, we use thousands of hourly rainfall records from all over the USA. The analysis indicates that heavier-tailed distributions describe better the observed hourly rainfall extremes in comparison to lighter tails. Traditional representations of the marginal distribution of hourly rainfall may significantly deviate from observed behaviours of extremes, with direct implications on hydroclimatic variables modelling and engineering design.

  12. Demographic and random amplified polymorphic DNA analyses reveal high levels of genetic diversity in a clonal violet.

    Science.gov (United States)

    Auge, H; Neuffer, B; Erlinghagen, F; Grupe, R; Brandl, R

    2001-07-01

    We performed demographic and molecular investigations on woodland populations of the clonal herb Viola riviniana in central Germany. We investigated the pattern of seedling recruitment, the amount of genotypic (clonal) variation and the partitioning of genetic variation among and within populations. Our demographic study was carried out in six violet populations of different ages and habitat conditions. It revealed that repeated seedling recruitment takes place in all of these populations, and that clonal propagation is accompanied by high ramet mortality. Our molecular investigations were performed on a subset of three of these six violet populations. Random amplified polymorphic DNA analyses using six primers yielded 45 scorable bands that were used to identify multilocus genotypes, i.e. putative clones. Consistent with our demographic results and independent of population age, we found a large genotypic diversity with a mean proportion of distinguishable genotypes of 0.93 and a mean Simpson's diversity index of 0.99. Using AMOVA we found a strong genetic differentiation among these violet populations with a PhiST value of 0.41. We suggest that a high selfing rate, limited gene flow due to short seed dispersal distances and drift due to founder effects are responsible for this pattern. Although Viola riviniana is a clonal plant, traits associated with sexual reproduction rather than clonality per se are moulding the pattern of genetic variation in this species.

  13. Brain responses to violet, blue, and green monochromatic light exposures in humans: prominent role of blue light and the brainstem.

    Directory of Open Access Journals (Sweden)

    Gilles Vandewalle

    Full Text Available BACKGROUND: Relatively long duration retinal light exposure elicits nonvisual responses in humans, including modulation of alertness and cognition. These responses are thought to be mediated in part by melanopsin-expressing retinal ganglion cells which are more sensitive to blue light than violet or green light. The contribution of the melanopsin system and the brain mechanisms involved in the establishment of such responses to light remain to be established. METHODOLOGY/PRINCIPAL FINDINGS: We exposed 15 participants to short duration (50 s monochromatic violet (430 nm, blue (473 nm, and green (527 nm light exposures of equal photon flux (10(13ph/cm(2/s while they were performing a working memory task in fMRI. At light onset, blue light, as compared to green light, increased activity in the left hippocampus, left thalamus, and right amygdala. During the task, blue light, as compared to violet light, increased activity in the left middle frontal gyrus, left thalamus and a bilateral area of the brainstem consistent with activation of the locus coeruleus. CONCLUSION/SIGNIFICANCE: These results support a prominent contribution of melanopsin-expressing retinal ganglion cells to brain responses to light within the very first seconds of an exposure. The results also demonstrate the implication of the brainstem in mediating these responses in humans and speak for a broad involvement of light in the regulation of brain function.

  14. Isolation and Characterization of Paracoccus sp. GSM2 Capable of Degrading Textile Azo Dye Reactive Violet 5

    Directory of Open Access Journals (Sweden)

    Mallikarjun C. Bheemaraddi

    2014-01-01

    Full Text Available A potential bacterial strain GSM2, capable of degrading an azo dye Reactive Violet 5 as a sole source of carbon, was isolated from textile mill effluent from Solapur, India. The 16S rDNA sequence and phenotypic characteristics indicated an isolated organism as Paracoccus sp. GSM2. This strain exhibited complete decolorization of Reactive Violet 5 (100 mg/L within 16 h, while maximally it could decolorize 800 mg/L of dye within 38 h with 73% decolorization under static condition. For color removal, the most suitable pH and temperature were pH 6.0–9.0 and 25–40°C, respectively. The isolate was able to decolorize more than 70% of five structurally different azo dyes within 38 h. The isolate is salt tolerant as it can bring out more than 90% decolorization up to a salt concentration of 2% (w/v. UV-Visible absorption spectra before and after decolorization suggested that decolorization was due to biodegradation and was further confirmed by FT-IR spectroscopy. Overall results indicate the effectiveness of the strain GSM2 explored for the treatment of textile industry effluents containing various azo dyes. To our knowledge, this could be the first report on biodegradation of Reactive Violet 5 by Paracoccus sp. GSM2.

  15. Genetic Basis of Spectral Tuning in the Violet-Sensitive Visual Pigment of African Clawed Frog, Xenopus laevis

    Science.gov (United States)

    Takahashi, Yusuke; Yokoyama, Shozo

    2005-01-01

    Ultraviolet (UV) and violet vision in vertebrates is mediated by UV and violet visual pigments that absorb light maximally (λmax) at ∼360 and 390–440 nm, respectively. So far, a total of 11 amino acid sites only in transmembrane (TM) helices I–III are known to be involved in the functional differentiation of these short wavelength-sensitive type 1 (SWS1) pigments. Here, we have constructed chimeric pigments between the violet pigment of African clawed frog (Xenopus laevis) and its ancestral UV pigment. The results show that not only are the absorption spectra of these pigments modulated strongly by amino acids in TM I–VII, but also, for unknown reasons, the overall effect of amino acid changes in TM IV–VII on the λmax-shift is abolished. The spectral tuning of the contemporary frog pigment is explained by amino acid replacements F86M, V91I, T93P, V109A, E113D, L116V, and S118T, in which V91I and V109A are previously unknown, increasing the total number of critical amino acid sites that are involved in the spectral tuning of SWS1 pigments in vertebrates to 13. PMID:16079229

  16. Intense, stable and excitation wavelength-independent photoluminescence emission in the blue-violet region from phosphorene quantum dots

    Science.gov (United States)

    Ge, Shuaipeng; Zhang, Lisheng; Wang, Peijie; Fang, Yan

    2016-06-01

    Nanoscale phosphorene quantum dots (PQDs) with few-layer structures were fabricated by pulsed laser ablation of a bulk black phosphorus target in diethyl ether. An intense and stable photoluminescence (PL) emission of the PQDs in the blue-violet wavelength region is clearly observed for the first time, which is attributed to electronic transitions from the lowest unoccupied molecular orbital (LUMO) to the highest occupied molecular orbital (HOMO) and occupied molecular orbitals below the HOMO (H-1, H-2), respectively. Surprisingly, the PL emission peak positions of the PQDs are not red-shifted with progressively longer excitation wavelengths, which is in contrast to the cases of graphene and molybdenum disulphide quantum dots. This excitation wavelength-independence is derived from the saturated passivation on the periphery and surfaces of the PQDs by large numbers of electron-donating functional groups which cause the electron density on the PQDs to be dramatically increased and the band gap to be insensitive to the quantum size effect in the PQDs. This work suggests that PQDs with intense, stable and excitation wavelength-independent PL emission in the blue-violet region have a potential application as semiconductor-based blue-violet light irradiation sources.

  17. Intense, stable and excitation wavelength-independent photoluminescence emission in the blue-violet region from phosphorene quantum dots.

    Science.gov (United States)

    Ge, Shuaipeng; Zhang, Lisheng; Wang, Peijie; Fang, Yan

    2016-06-06

    Nanoscale phosphorene quantum dots (PQDs) with few-layer structures were fabricated by pulsed laser ablation of a bulk black phosphorus target in diethyl ether. An intense and stable photoluminescence (PL) emission of the PQDs in the blue-violet wavelength region is clearly observed for the first time, which is attributed to electronic transitions from the lowest unoccupied molecular orbital (LUMO) to the highest occupied molecular orbital (HOMO) and occupied molecular orbitals below the HOMO (H-1, H-2), respectively. Surprisingly, the PL emission peak positions of the PQDs are not red-shifted with progressively longer excitation wavelengths, which is in contrast to the cases of graphene and molybdenum disulphide quantum dots. This excitation wavelength-independence is derived from the saturated passivation on the periphery and surfaces of the PQDs by large numbers of electron-donating functional groups which cause the electron density on the PQDs to be dramatically increased and the band gap to be insensitive to the quantum size effect in the PQDs. This work suggests that PQDs with intense, stable and excitation wavelength-independent PL emission in the blue-violet region have a potential application as semiconductor-based blue-violet light irradiation sources.

  18. Quenching of fluorescence by crystal violet and its use to differentiate between surface-bound and internalized bacteria

    Science.gov (United States)

    Mathew, S.; Lim, Y. C.; Kishen, A.

    2008-06-01

    Phagocytosis is a complex process involving attachment, ingestion and intracellular processing of bacteria by phagocytes. A great difficulty in the evaluation of this process is to differentiate between attachment of the particles to the cell surface and internalization of the particles by the cells. Various techniques have been used to differentiate internalized and surface-attached bacteria in cultured cells, but only a few permit differentiations between surface-bound and internalized bacteria. In this study the quenching of fluorescence by crystal violet on acridine orange stained bacterial biofilm and planktonic bacterial cells is used to differentiate between surface-bound and internalized bacteria within macrophages. Method: One week old Enterococcus faecalis biofilm was grown on perspex and glass substrates in All-Culture medium (nutrient-rich condition) and phosphate buffered saline (nutrient-deprived condition). As model systems, human monocytic (THP-1) and histiocytic (U937) cell lines were used. These cell lines were incubated with the biofilm bacteria for 4 hrs in CO II incubator at 37 °C. The cells and bacteria were stained with acridine orange and quenched with crystal violet to distinguish between surface-bound and internalized bacteria. Results: The presence of green-fluorescing internalized bacteria was detected within the macrophages under the planktonic, nutrient-rich and nutrient-deprived biofilm conditions. All infecting bacteria take up acridine orange and fluoresced green, crystal violet quenched the fluorescence of extra-cellular adhering bacteria so that only fluorescent intracellular bacteria would be visible under fluorescent light microscopy.

  19. Ultra-light dark matter in ultra-faint dwarf galaxies

    Science.gov (United States)

    Calabrese, Erminia; Spergel, David N.

    2016-08-01

    Cold Dark Matter (CDM) models struggle to match the observations at galactic scales. The tension can be reduced either by dramatic baryonic feedback effects or by modifying the particle physics of CDM. Here, we consider an ultra-light scalar field DM particle manifesting a wave nature below a DM particle mass-dependent Jeans scale. For DM mass m ˜ 10-22 eV, this scenario delays galaxy formation and avoids cusps in the centre of the dark matter haloes. We use new measurements of half-light mass in ultra-faint dwarf galaxies Draco II and Triangulum II to estimate the mass of the DM particle in this model. We find that if the stellar populations are within the core of the density profile then the data are in agreement with a Wave Dark Matter model having a DM particle with m ˜ 3.7-5.6 × 10-22 eV. The presence of this extremely light particle will contribute to the formation of a central solitonic core replacing the cusp of a Navarro-Frenk-White profile and bringing predictions closer to observations of cored central density in dwarf galaxies.

  20. Ultra-Light Dark Matter in Ultra-Faint Dwarf Galaxies

    CERN Document Server

    Calabrese, Erminia

    2016-01-01

    Cold Dark Matter (CDM) models struggle to match the observations at galactic scales. The tension can be reduced either by dramatic baryonic feedback effects or by modifying the particle physics of CDM. Here, we consider an ultra-light scalar field DM particle manifesting a wave nature below a DM particle mass-dependent Jeans scale. For DM mass $m\\sim10^{-22}{\\rm eV}$, this scenario delays galaxy formation and avoids cusps in the center of the dark matter haloes. We use new measurements of half-light mass in ultra-faint dwarf galaxies Draco II and Triangulum II to estimate the mass of the DM particle in this model. We find that if the stellar populations are within the core of the density profile then the data are in agreement with a wave dark matter model having a DM particle with $m\\sim 3.7-5.6\\times 10^{-22}{\\rm eV}$. The presence of this extremely light particle will contribute to the formation of a central solitonic core replacing the cusp of a Navarro-Frenk-White profile and bringing predictions closer t...

  1. Progress in ultra high energy neutrino experiments using radio techniques

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jiali [Physics department, Kunming University, Kunming, 650214 (China); Tiedt, Douglas [Physics department, South Dakota School of Mines and Technology, Rapid City, SD, 57701-3995 (United States)

    2013-05-23

    Studying the source of Ultra High Energy Cosmic Ray (UHECR) can provide important clues on the understanding of UHE particle physics, astrophysics, and other extremely energetic phenomena in the universe. However, charged CR particles are deflected by magnetic fields and can not point back to the source. Furthermore, UHECR charged particles above the Greisen-Zatsepin-Kuzmin (GZK) cutoff (about 5 Multiplication-Sign 10{sup 19} eV) suffer severe energy loss due to the interaction with the Cosmic Microwave Background Radiation (CMBR). Consequently almost all the information carried by CR particles about their origin is lost. Neutrinos, which are neutral particles and have extremely weak interactions with other materials can arrive at the earth without deflection and absorption. Therefore UHE neutrinos can be traced back to the place where they are produced. Due to their weak interaction and ultra high energies (thus extremely low flux) the detection of UHE neutrinos requires a large collecting area and massive amounts of material. Cherenkov detection at radio frequency, which has long attenuation lengths and can travel freely in natural dense medium (ice, rock and salt et al), can fulfill the detection requirement. Many UHE neutrino experiments are being performed by radio techniques using natural ice, lunar, and salt as detection mediums. These experiments have obtained much data about radio production, propagation and detection, and the upper limit of UHE neutrino flux.

  2. SciDAC Institute for Ultra-Scale Visualization: Activity Recognition for Ultra-Scale Visualization

    Energy Technology Data Exchange (ETDEWEB)

    Silver, Deborah [Rutgers Univ., Piscataway, NJ (United States)

    2014-04-30

    Understanding the science behind ultra-scale simulations requires extracting meaning from data sets of hundreds of terabytes or more. Developing scalable parallel visualization algorithms is a key step enabling scientists to interact and visualize their data at this scale. However, at extreme scales, the datasets are so huge, there is not even enough time to view the data, let alone explore it with basic visualization methods. Automated tools are necessary for knowledge discovery -- to help sift through the information and isolate characteristic patterns, thereby enabling the scientist to study local interactions, the origin of features and their evolution in large volumes of data. These tools must be able to operate on data of this scale and work with the visualization process. In this project, we developed a framework for activity detection to allow scientists to model and extract spatio-temporal patterns from time-varying data.

  3. Classifying Returns as Extreme

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    2014-01-01

    I consider extreme returns for the stock and bond markets of 14 EU countries using two classification schemes: One, the univariate classification scheme from the previous literature that classifies extreme returns for each market separately, and two, a novel multivariate classification scheme tha...

  4. Liquid-liquid extraction combined with high performance liquid chromatography-diode array-ultra-violet for simultaneous determination of antineoplastic drugs in plasma

    Directory of Open Access Journals (Sweden)

    Ananda Lima Sanson

    2011-06-01

    Full Text Available A liquid-liquid extraction (LLE combined with high-performance liquid chromatography-diode array detection method for simultaneous analysis of four chemically and structurally different antineoplastic drugs (cyclophosphamide, doxorubicin, 5-fluorouracil and ifosfamide was developed. The assay was performed by isocratic elution, with a C18 column (5 µm, 250 x 4.6 mm and mobile phase constituted by water pH 4.0- acetonitrile-methanol (68:19:13, v/v/v, which allowed satisfactory separation of the compounds of interest. LLE, with ethyl acetate, was used for sample clean-up with recoveries ranging from 60 to 98%. The linear ranges were from 0.5 to 100 µg mL-1, for doxorubicin and 1 to 100 µg mL-1, for the other compounds. The relative standard deviations ranged from 5.5 to 17.7%. This method is a fast and simple alternative that can be used, simultaneously, for the determination of the four drugs in plasma, with a range enabling quantification of the drugs in pharmacokinetics, bioequivalence and therapeutic drug-monitoring studies.Um método de extração líquido-líquido (ELL combinado com cromatografia líquida de alta eficiência-detector de arranjo de diodos foi desenvolvido para análise simultânea de quatro fármacos antineoplásicos quimicamente e estruturalmente diferentes (ciclofosfamida, doxorrubicina, fluoruracila e ifosfamida. O estudo foi realizado sob condições isocráticas, com coluna C18 (5µm, 250 x 4.6 mm e fase móvel constituída por água pH 4.0-acetonitrila-metanol (68:19:13, v/v/v, que permitiu separação satisfatória dos analitos de interesse. A ELL, com acetato de etila, foi utilizada para limpeza da amostra, com recuperação variando de 60 a 98%. As faixas foram lineares de 0,5 a 100 µg mL-1 para doxorrubicina e 1 a 100 µg mL-1 para os outros compostos. O desvio padrão relativo variou de 5,5 a 17,7%. Este método é uma alternativa rápida e simples que pode ser usado, simultaneamente, para a determinação dos quatro fármacos em plasma, com uma faixa que permite quantificá-los em estudos de farmacocinética, bioequivalência e monitorização terapêutica.

  5. Tuning of ultra-violet to green emission by choosing suitable excitation wavelength in ZnO: Quantum dot, nanocrystals and bulk

    Energy Technology Data Exchange (ETDEWEB)

    Singh, L. Robindro [Department of Physics, PU College, Mizoram University, Aizawal, 796001 (India); Ningthoujam, R.S., E-mail: rsn@barc.gov.i [Chemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085 (India); Singh, S. Dorendrajit [Department of Physics, Manipur University, Canchipur, 795 003 (India)

    2009-11-13

    ZnO particles (quantum dots to bulk) have been prepared using urea hydrolysis and are dispersible in methanol. In photoluminescence study, as-prepared sample shows the main emission peaks at 375 and 394 nm, which are assigned to the exciton and band-edge emissions, respectively. The former peak disappears when as-prepared sample is heated at 300, 500, 700 and 900 deg. C due to particle size effect. Interestingly, higher heated samples shows emission peak at 505 nm and it is attributed to oxygen vacancy created in ZnO lattice. The intensity ratio of UV-light at 394 nm to green light at 505 nm can be adjusted by choosing suitable excitation wavelengths and also particle size or heat-treatment. Optimum emission intensities at 394 and 505 nm can be obtained on 360-370 and 320-330 nm excitations, respectively. These materials will be useful in optoelectronic applications.

  6. Climatology of Ultra Violet (UV) irradiance as measured through the Belgian ground-based monitoring network during the time period of 1995-2014

    Science.gov (United States)

    Pandey, Praveen; Gillotay, Didier; Depiesse, Cedric

    2016-04-01

    In this study we describe the network of ground-based ultraviolet (UV) radiation monitoring stations in Belgium. The evolution of the entire network, together with the details of measuring instruments is given. The observed cumulative irradiances -UVB, UVA and total solar irradiance (TSI)- over the course of measurement for three stations -a northern (Ostende), central (Uccle) and a southern (Redu)- are shown. The longest series of measurement shown in this study is at Uccle, Brussels, from 1995 till 2014. Thus, the variation of the UV index (UVI), together with the variation of irradiances during summer and winter months at Uccle are shown as a part of this climatological study. The trend of UVB irradiance over the above mentioned three stations is shown. This UVB trend is studied in conjunction with the long-term satellite-based total column ozone value over Belgium, which shows two distinct trends marked by a change point. The total column ozone trend following the change point is positive. It is also seen that the UVB trend is positive for the urban/sub-urban sites: Uccle and Redu. Whereas the UVB trend at Ostende, which is a coastal site, is not positive. A possible explanation of this relation between total column ozone and UVB trend could be associated with aerosols, which is shown in this paper by means of a radiative transfer model based study -as a part of a preliminary investigation. It is seen that the UVI is influenced by the type of aerosols.

  7. Climatology of Ultra Violet(UV) Irradiance at the Surface of the Earth as Measured by the Belgian UV Radiation Monitoring Network

    Science.gov (United States)

    Pandey, Praveen; Gillotay, Didier; Depiesse, Cedric

    2016-08-01

    In this paper we describe the network of ground-based ultraviolet (UV) radiation monitoring stations in Belgium. The evolution of the entire network, together with the details of measuring instruments is given. The observed cumulative irradiations -UVB, UVA and total solar irradiation (TSI)- over the course of measurement for three stations -a northern (Ostende), central (Uccle) and a southern (Redu)- are shown. The longest series of measurement shown in this study is at Uccle, Brussels, from 1995 till 2014. Thus, the variation of the UV index, together with the variation of irradiations during summer and winter months at Uccle are shown as a part of this climatological study. The trend of UVB irradiance over the above mentioned three stations is shown. This UVB trend is studied in conjunction with the long-term satellite-based total column ozone value over Belgium, which shows two distinct trends marked by a change point. The total column ozone trend following the change point is positive. It is also seen that the UVB trend is positive for the urban/sub-urban sites: Uccle and Redu. Whereas the UVB trend at Ostende, which is a coastal site, is not positive. A possible explanation of this relation between total column ozone and UVB trend could be associated with aerosols, which is shown in this paper by means of a radiative transfer model based study -as a part of a preliminary investigation. It is seen that the UVI is influenced by the type of aerosols.

  8. Specific behavior of the p-aminothiophenol--silver sol system in their Ultra-Violet-Visible (UV-Visible) and Surface Enhanced Raman (SERS) spectra.

    Science.gov (United States)

    Firkala, Tamás; Tálas, Emília; Mihály, Judith; Imre, Tímea; Kristyán, Sándor

    2013-11-15

    The UV-Visible and Surface Enhanced Raman Spectroscopy (SERS) behavior of silver sol (a typical SERS agent) were studied in the presence of different bifunctional thiols such as p-aminothiophenol, p-mercaptobenzoic acid, p-nitrothiophenol, p-aminothiophenol hydrochloride, and 2-mercaptoethylamine hydrochloride in diluted aqueous solution. Our results confirm that the p-aminothiophenol induced aggregation of citrate stabilized silver colloid originates from its electrostatic nature, as well as the azo-bridge formation cannot be the reason of the observed time dependent UV-Visible spectra. Based on our parallel SERS and electrospray ionization mass spectrometry measurements, we have concluded that certain amount of oxidized form of the probe molecule has to be present for the so-called b2-mode enhancement in the SERS spectrum of p-aminothiophenol. Our findings seem to support the idea that the azo-bridge formation is responsible for the b2-mode enhancement in the SERS spectrum of p-aminothiophenol. Copyright © 2013 Elsevier Inc. All rights reserved.

  9. Development of one-step hollow fiber supported liquid phase sampling technique for occupational workplace air analysis using high performance liquid chromatography with ultra-violet detector.

    Science.gov (United States)

    Yan, Cheing-Tong; Chien, Hai-Ying

    2012-07-13

    In this study, a simple and novel one-step hollow-fiber supported liquid-phase sampling (HF-LPS) technique was developed for enriched sampling of gaseous toxic species prior to chemical analysis for workplace air monitoring. A lab-made apparatus designed with a gaseous sample generator and a microdialysis sampling cavity (for HF-LPS) was utilized and evaluated to simulate gaseous contaminant air for occupational workplace analysis. Gaseous phenol was selected as the model toxic species. A polyethersulfone hollow fiber dialysis module filled with ethylene glycol in the shell-side was applied as the absorption solvent to collect phenol from a gas flow through the tube-side, based on the concentration distribution of phenol between the absorption solvent and the gas flow. After sampling, 20 μL of the extractant was analyzed by high performance liquid chromatography with ultraviolet detection (HPLC-UV). Factors that influence the generation of gaseous standards and the HF-LPS were studied thoroughly. Results indicated that at 25 °C the phenol (2000 μg/mL) standard solution injected at 15-μL/min can be vaporized into sampling cavity under nitrogen flow at 780 mL/min, to generate gaseous phenol with concentration approximate to twice the permissible exposure limit. Sampling at 37.3 mL/min for 30 min can meet the requirement of the workplace air monitoring. The phenol in air ranged between 0.7 and 10 cm³/m³ (shows excellent linearity) with recovery between 98.1 and 104.1%. The proposed method was identified as a one-step sampling for workplace monitoring with advantages of convenience, rapidity, sensitivity, and usage of less-toxic solvent. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Tunable High Power Picosecond Laser in Ultra-violet%皮秒级高功率紫外可调谐激光

    Institute of Scientific and Technical Information of China (English)

    王丽; 黄骝

    2001-01-01

    采用355 nm主被动锁模YAG激光器作抽运源,结合BBO晶体的倍频调谐特性,获得了200~350 nm的皮秒级紫外可调谐激光,转换效率为15.3%~23.6%.对影响参量光倍频转换效率的发散角、线宽进行模拟和分析,其结果与实验吻合.%Utilizing SHG tunable feature of nonlinear crystal BBO, an experiment of UV tunable laser in 200~350 nm with conversion efficiency from 15.3% to 23.6% has been demonstrated. The influence of the divergence angle and the linewidth of the incident parametric light on the SHG conversion is calculated and compared with the experiments.

  11. The Use of Ultra-Violet (UV) Light Emitting Diodes (LEDS) in an Advanced Oxidation Process (AOP) with Brilliant Blue FCF as an Indicator

    Science.gov (United States)

    2015-03-26

    tasks of graduate school. Thank you for being my wife and mother to our beautiful daughter. You both have my word that I will do my best to make sure...H2O2 in solution Fill remainder of flask with reverse osmosis deionized water up to the 1 liter mark Drop in stir bar and place on stir plate ...instrument Close the panel Click “Zero” Retrieve solution from the stir plate . Make Calibration Samples (0%, 25%, 50%, 75%, 100%) Using a

  12. Vacuum ultra-violet emission of CF4 and CF3I containing plasmas and Their effect on low-k materials

    Science.gov (United States)

    el Otell, Z.; Šamara, V.; Zotovich, A.; Hansen, T.; de Marneffe, J.-F.; Baklanov, M. R.

    2015-10-01

    CF3I was suggested as a replacement of CF4 gas to decrease the plasma-induced damage (PID) on low-k dielectrics during etching. This proposal is investigated by means of plasma emission measurements and material characterisation. The experiments were conducted in a 300 mm capacitively coupled plasma source. The vacuum ultraviolet (VUV, 30≤slant λ ≤slant 220 nm) plasma emission was measured for discharges generated in a pure or a mixture of argon, CF4 and/or CF3I, since VUV plays a major role in PID. However, CF3I containing discharges were found to have a stronger emission than CF4 in the VUV range. Nevertheless, Fourier transform infra-red spectroscopy and κ-value measurements showed that there is almost no difference between the damage caused by CF3I or CF4 containing plasmas, while etching in a capacitively coupled plasma source. It is proposed that the damage caused by CF3I with lower F*-density but higher VUV-photon flux is similar to the damage caused by CF4, with higher F*-density but lower VUV-photon flux.

  13. Degradation of picric acid and 2,6-DNT in marine sediments and waters: The role of microbial activity and ultra-violet exposure

    Science.gov (United States)

    Nipper, Marion; Qian, Yaorong; Carr, R. Scott; Miller, Karen

    2004-01-01

    Bio- and photo-transformation of two munitions and explosives of concern, 2,6-dinitrotoluene (2,6-DNT) and 2,4,6-trinitrophenol (picric acid) were assessed in spiked marine sediments and water. A sandy and a fine-grained sediment, with 0.25% and 1.1% total organic carbon, respectively, were used for biotransformation assessments at 10 and 20 °C. Sterilized sediments were used as controls for biotic vs. abiotic transformation. Transformation products were analyzed by HPLC, GC/MS and LC/MS. Biotransformation in sediments started soon after the initial contact of the chemicals with the sediments and proceeded for several months, with rates in the following sequence: fine-grain at 20 °C > fine-grain at 10 °C > sand at 20 °C > sand at 10 °C. The biotransformation paths seemed to be similar for all conditions. The major biotransformation product of 2,6-DNT was 2-amino-6-nitrotoluene (2-A-6-NT). 2-Nitrotoluene (2-NT) and other minor components, including N,N-dimethyl-3-nitroaniline, benzene nitrile, methylamino-2-nitrosophenol and diaminophenol, were also identified. After more prolonged incubation these chemicals were replaced by high molecular weight polymers. Several breakdown products of picric acid were identified by GC/MS, including 2,4-dinitrophenol, amino dinitrophenols, 3,4-diamino phenol, amino nitrophenol and nitro diaminophenol. Photo-transformation of 2,6-DNT and picric acid in seawater was assessed under simulated solar radiation (SSR). No significant photolysis of picric acid in seawater was observed for up to 47 days, but photo-transformation of 2,6-DNT began soon after the initial exposure to SSR, with 89% being photo-transformed in 24 h and none remaining after 72 h. High molecular weight chemicals were generated, with mass spectra ranging from molecular weight 200–500 compared to 182 for DNT, and the color of the stock solution changed from clear to orange. Complexity of the mass spectra and mass differences among fragments suggest that multiple polymers were produced and were co-eluting during the LC/MS analyses.

  14. Collective electronic excitations in the ultra violet regime in 2-D and 1-D carbon nanostructures achieved by the addition of foreign atoms

    Science.gov (United States)

    Bangert, U.; Pierce, W.; Boothroyd, C.; Pan, C.-T.; Gwilliam, R.

    2016-06-01

    Plasmons in the visible/UV energy regime have attracted great attention, especially in nano-materials, with regards to applications in opto-electronics and light harvesting; tailored enhancement of such plasmons is of particular interest for prospects in nano-plasmonics. This work demonstrates that it is possible, by adequate doping, to create excitations in the visible/UV regime in nano-carbon materials, i.e., carbon nanotubes and graphene, with choice of suitable ad-atoms and dopants, which are introduced directly into the lattice by low energy ion implantation or added via deposition by evaporation. Investigations as to whether these excitations are of collective nature, i.e., have plasmonic character, are carried out via DFT calculations and experiment-based extraction of the dielectric function. They give evidence of collective excitation behaviour for a number of the introduced impurity species, including K, Ag, B, N, and Pd. It is furthermore demonstrated that such excitations can be concentrated at nano-features, e.g., along nano-holes in graphene through metal atoms adhering to the edges of these holes.

  15. OH SENSOR BASED ON ULTRA-VIOLET, CONTINUOUS-WAVE ABSORPTION SPECTROSCOPY UTILIZING A FREQUENCY-QUADRUPLED, FIBER-AMPLIFIED EXTERNAL CAVITY DIODE LASER. (R828180)

    Science.gov (United States)

    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  16. Plasma physics of extreme astrophysical environments.

    Science.gov (United States)

    Uzdensky, Dmitri A; Rightley, Shane

    2014-03-01

    Among the incredibly diverse variety of astrophysical objects, there are some that are characterized by very extreme physical conditions not encountered anywhere else in the Universe. Of special interest are ultra-magnetized systems that possess magnetic fields exceeding the critical quantum field of about 44 TG. There are basically only two classes of such objects: magnetars, whose magnetic activity is manifested, e.g., via their very short but intense gamma-ray flares, and central engines of supernovae (SNe) and gamma-ray bursts (GRBs)--the most powerful explosions in the modern Universe. Figuring out how these complex systems work necessarily requires understanding various plasma processes, both small-scale kinetic and large-scale magnetohydrodynamic (MHD), that govern their behavior. However, the presence of an ultra-strong magnetic field modifies the underlying basic physics to such a great extent that relying on conventional, classical plasma physics is often not justified. Instead, plasma-physical problems relevant to these extreme astrophysical environments call for constructing relativistic quantum plasma (RQP) physics based on quantum electrodynamics (QED). In this review, after briefly describing the astrophysical systems of interest and identifying some of the key plasma-physical problems important to them, we survey the recent progress in the development of such a theory. We first discuss the ways in which the presence of a super-critical field modifies the properties of vacuum and matter and then outline the basic theoretical framework for describing both non-relativistic and RQPs. We then turn to some specific astrophysical applications of relativistic QED plasma physics relevant to magnetar magnetospheres and to central engines of core-collapse SNe and long GRBs. Specifically, we discuss the propagation of light through a magnetar magnetosphere; large-scale MHD processes driving magnetar activity and responsible for jet launching and propagation in

  17. Plasma physics of extreme astrophysical environments

    Science.gov (United States)

    Uzdensky, Dmitri A.; Rightley, Shane

    2014-03-01

    Among the incredibly diverse variety of astrophysical objects, there are some that are characterized by very extreme physical conditions not encountered anywhere else in the Universe. Of special interest are ultra-magnetized systems that possess magnetic fields exceeding the critical quantum field of about 44 TG. There are basically only two classes of such objects: magnetars, whose magnetic activity is manifested, e.g., via their very short but intense gamma-ray flares, and central engines of supernovae (SNe) and gamma-ray bursts (GRBs)—the most powerful explosions in the modern Universe. Figuring out how these complex systems work necessarily requires understanding various plasma processes, both small-scale kinetic and large-scale magnetohydrodynamic (MHD), that govern their behavior. However, the presence of an ultra-strong magnetic field modifies the underlying basic physics to such a great extent that relying on conventional, classical plasma physics is often not justified. Instead, plasma-physical problems relevant to these extreme astrophysical environments call for constructing relativistic quantum plasma (RQP) physics based on quantum electrodynamics (QED). In this review, after briefly describing the astrophysical systems of interest and identifying some of the key plasma-physical problems important to them, we survey the recent progress in the development of such a theory. We first discuss the ways in which the presence of a super-critical field modifies the properties of vacuum and matter and then outline the basic theoretical framework for describing both non-relativistic and RQPs. We then turn to some specific astrophysical applications of relativistic QED plasma physics relevant to magnetar magnetospheres and to central engines of core-collapse SNe and long GRBs. Specifically, we discuss the propagation of light through a magnetar magnetosphere; large-scale MHD processes driving magnetar activity and responsible for jet launching and propagation in

  18. An LED Approach for Measuring the Photocatalytic Breakdown of Crystal Violet Dye

    Science.gov (United States)

    Ryan, Robert E.; Underwood, Lauren W.; ONeal, Duane; Pagnutti, Mary; Davis, Bruce A.

    2009-01-01

    A simple technique to assess the reactivity of photocatalytic coatings sprayed onto transmissive glass surfaces was developed. This new method uses ultraviolet (UV) gallium nitride (GaN) light-emitting diodes (LEDs) to drive a photocatalytic reaction (the photocatalytic breakdown of a UV-resistant dye applied to a surface coated with the semiconductor titanium dioxide); and then a combination of a stabilized white light LED and a spectrometer to track the dye degradation as a function of time. Simple, standardized evaluation techniques that assess photocatalytic materials over a variety of environmental conditions, including illumination level, are not generally available and are greatly needed prior to in situ application of photocatalytic technologies. To date, much research pertaining to this aspect of photocatalysis has been limited and has focused primarily on laboratory experiments using mercury lamps. Mercury lamp illumination levels are difficult to control over large ranges and are temporally modulated by line power, limiting their use in helping to understand and predict how photocatalytic materials will behave in natural environmental settings and conditions. The methodology described here, using steady-state LEDs and time series spectroradiometric techniques, is a novel approach to explore the effect of UV light on the photocatalytic degradation of a UV resistant dye (crystal violet). GaN UV LED arrays, centered around 365 nm with an adjustable DC power supply, are used to create a small, spatially uniform light field where the steady state light level can be varied over three to four orders of magnitude. For this study, a set of glass microscope slides was custom coated with a thinly sprayed layer of photocatalytic titanium dioxide. Crystal violet was then applied to these titanium-dioxide coated slides and to uncoated control slides. The slides were then illuminated at various light levels from the dye side of the slide by the UV LED array. To monitor

  19. Ultra preconcentration of polycyclic aromatic hydrocarbons in smoked bacon by a combination of SPE and DLLME.

    Science.gov (United States)

    Liu, Xiaofang; Zhou, Shu; Zhu, Quanfei; Ye, Yong; Chen, Huaixia

    2014-09-01

    A sample pretreatment method, solid-phase extraction combined with dispersive liquid-liquid microextraction (SPE-DLLME), was established for the sensitive determination of polycyclic aromatic hydrocarbons (PAHs) in smoked bacon samples. In the SPE-DLLME process, three PAHs including naphthalene (Naph), phenanthrene (Phen) and pyrene (Pyr) were extracted from samples and transferred into C18 SPE cartridge. The target analytes were subsequently eluted with 1.2 ml of acetonitrile-dichloromethane (5:1, v/v) mixture solution. The eluent was injected directly into the 5.0 ml ultrapure water in the subsequent DLLME procedure. The sedimented phase was concentrated under a gentle nitrogen flow to 120.0 µl. Finally, the analytes in the extraction solvent were determined by high-performance liquid chromatography with a ultra-violet detector. Some important extraction parameters affecting the performance, such as the sample solution flow rate, breakthrough volume, salt addition as well as the type and volume of the elution solvent were optimized. The developed method provided an ultra enrichment factors for PAHs ranged from 3478 to 3824. The method was applied for the selective extraction and sensitive determination of PAHs in smoked bacon samples. The limits of detection (S/N = 3) were 0.05, 0.01, 0.02 μg kg(-1) for Naph, Phen, Pyr, respectively.

  20. Modelling Carbon Radio Recombination Line observation towards the Ultra-Compact HII region W48A

    CERN Document Server

    Jeyakumar, S

    2013-01-01

    We model Carbon Recombination Line (CRL) emission from the Photo Dissociation Region (PDR) surrounding the Ultra-Compact (UC) HII region W48A. Our modelling shows that the inner regions ($A_V \\sim 1$) of the CII layer in the PDR contribute significantly to the CRL emission. The dependence of line ratios of CRL emission with the density of the PDR and the far ultra-violet (FUV) radiation incident on the region is explored over a large range of these parameters that are typical for the environments of UCHII regions. We find that by observing a suitable set of CRLs it is possible to constrain the density of the PDR. If the neutral density in the PDR is high ($\\gtrsim 10^7$ \\cmthree) CRL emission is bright at high frequencies ($\\gtrsim 20$ GHz), and absorption lines from such regions can be detected at low frequencies ($\\lesssim 10$ GHz). Modelling CRL observations towards W48A shows that the UCHII region is embedded in a molecular cloud of density of about $4 \\times$ 10$^7$ \\cmthree.

  1. Past, Present and Future of Ultra-Slow Muons

    Science.gov (United States)

    Nagamine, Kanetada

    Experimental works towards a realization of the ultra-slow positive muon by laser resonant ionization of thermal muonium (USM) in 1995 are reviewed with reference to the other methods. Then a short description is given for the present USM project at J-PARC MUSE. Finally, possible future projects at J-PARC MUSE are presented, with a particular emphasis on the fundamental atomic physics of extreme muonic atomic states, µ+µ- atoms which would only be produced, along with the UCM, by a possible development of a slow and narrow µ- beam for which some ideas are given.

  2. Chemical enrichment in Ultra-Faint Dwarf galaxies

    Science.gov (United States)

    Romano, Donatella

    2016-08-01

    Our view of the Milky Way's satellite population has radically changed after the discovery, ten years ago, of the first Ultra-Faint Dwarf galaxies (UFDs). These extremely faint, dark-matter dominated, scarcely evolved stellar systems are found in ever-increasing number in our cosmic neighbourhood and constitute a gold-mine for studies of early star formation conditions and early chemical enrichment pathways. Here we show what can be learned from the measurements of chemical abundances in UFD stars read through the lens of chemical evolution studies, point out the limitations of the classic approach, and discuss the way to go to improve the models.

  3. Ultra low frequency waves impact on radiation belt energetic particles

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    One of the most fundamental important issues in the space physics is to understand how solar wind energy transports into the inner magnetosphere.Ultra low frequency(ULF)wave in the magnetosphere and its impact on energetic particles,such as the wave-particle resonance,modulation,and particle acceleration,are extremely important topics in the Earth’s radiation belt dynamics and solar wind― magnetospheric coupling.In this review,we briefly introduce the recent advances on ULF waves study. Further,we will explore the density structures and ion compositions around the plasmaspheric boundary layer(PBL)and discuss its possible relation to the ULF waves.

  4. Ultra low frequency waves impact on radiation belt energetic particles

    Institute of Scientific and Technical Information of China (English)

    ZONG QiuGang; HAO YongQiang; WANG YongFu

    2009-01-01

    One of the most fundamental important issues in the space physics is to understand how solar wind energy transports into the inner magnetosphere.Ultra low frequency(ULF)wave in the magnetosphere and its impact on energetic particles,such as the wave-particle resonance,modulation,and particle acceleration,are extremely important topics in the Earth's radiation belt dynamics and solar windmagnetospheric coupling.In this review,we briefly introduce the recent advances on ULF waves study.Further,we will explore the density structures and ion compositions around the plasmaspheric boundary layer(PBL)and discuss its possible relation to the ULF waves.

  5. Indirect differential pulse voltammetric determination of aluminum by a pyrocatechol violet-modified electrode

    Energy Technology Data Exchange (ETDEWEB)

    Chen, G.; Bi, S.; Dai, L.; Cao, M.; Chen, Y. Wang, X. [Nanjing Univ. (China)

    1999-03-01

    Aluminum is one of the abundant elements in the earth`s crust. It has been considered to be a causative agent for various neurological disorders such as Alzheimer Senile, presenile dementia and amyotrophic lateral sclerosis. It is also very harmful to plants and aquatic organisms. Therefore, the determination of Al is very important. A Pyrocatechol Violet (PCV) modified electrode for the voltammetric determination of aluminum is reported. The modified electrode is simply prepared by dip-coating a pyrolytic graphite electrode in a NaAc-HAc buffer solution of PCV. Optimum experimental conditions for aluminum determination include a 0.2 mol/L NaAc-HAc buffer solution of pH 4.8, a PCV concentration of 0.02 mol/L used to modify the electrode and the use of differential-pulse mode for measurement. The peak currents of differential pulse voltammograms (DPV) decrease with the addition of Al into the buffer solution while the peak potentials remain the same. The decreasing value of peak current {Delta}i{sub p} is linear with Al concentration in the range of 1{times}10{sup {minus}8} to 1{times}10{sup {minus}7} mol/L and 1{times}10{sup {minus}7} to 1{times}10{sup {minus}6} mol/L. The detection limit is 5{times}10{sup {minus}9} mol/L and the relative standard deviation for 4{times}10{sup {minus}8} mol/L Al is 2.9% (n=8). The stability of this electrode is satisfactory. No serious interference is found. This method has been applied to determine Al in drinking water samples.

  6. Blue-violet laser modification of titania treated titanium: antibacterial and osteo-inductive effects.

    Directory of Open Access Journals (Sweden)

    Takanori Kawano

    Full Text Available BACKGROUND: Many studies on surface modifications of titanium have been performed in an attempt to accelerate osseointegration. Recently, anatase titanium dioxide has been found to act as a photocatalyst that expresses antibiotic properties and exhibits hydrophilicity after ultraviolet exposure. A blue-violet semiconductor laser (BV-LD has been developed as near-ultraviolet light. The purpose of this study was to investigate the effects of exposure to this BV-LD on surface modifications of titanium with the goal of enhancing osteoconductive and antibacterial properties. METHODS: The surfaces of pure commercial titanium were polished with #800 waterproof polishing papers and were treated with anatase titania solution. Specimens were exposed using BV-LD (λ = 405 nm or an ultraviolet light-emitting diode (UV-LED, λ = 365 nm at 6 mW/cm(2 for 3 h. The surface modification was evaluated physically and biologically using the following parameters or tests: surface roughness, surface temperature during exposure, X-ray diffraction (XRD analysis, contact angle, methylene blue degradation tests, adherence of Porphyromonas gingivalis, osteoblast and fibroblast proliferation, and histological examination after implantation in rats. RESULTS: No significant changes were found in the surface roughness or XRD profiles after exposure. BV-LD exposure did not raise the surface temperature of titanium. The contact angle was significantly decreased, and methylene blue was significantly degraded. The number of attached P. gingivalis organisms was significantly reduced after BV-LD exposure compared to that in the no exposure group. New bone was observed around exposed specimens in the histological evaluation, and both the bone-to-specimen contact ratio and the new bone area increased significantly in exposed groups. CONCLUSIONS: This study suggested that exposure of titanium to BV-LD can enhance the osteoconductivity of the titanium surface and induce antibacterial

  7. A simple method for studying the molecular mechanisms of ultraviolet and violet reception in vertebrates.

    Science.gov (United States)

    Yokoyama, Shozo; Tada, Takashi; Liu, Yang; Faggionato, Davide; Altun, Ahmet

    2016-03-22

    Many vertebrate species use ultraviolet (UV) reception for such basic behaviors as foraging and mating, but many others switched to violet reception and improved their visual resolution. The respective phenotypes are regulated by the short wavelength-sensitive (SWS1) pigments that absorb light maximally (λmax) at ~360 and 395-440 nm. Because of strong epistatic interactions, the biological significance of the extensive mutagenesis results on the molecular basis of spectral tuning in SWS1 pigments and the mechanisms of their phenotypic adaptations remains uncertain. The magnitudes of the λmax-shifts caused by mutations in a present-day SWS1 pigment and by the corresponding forward mutations in its ancestral pigment are often dramatically different. To resolve these mutagenesis results, the A/B ratio, in which A and B are the areas formed by amino acids at sites 90, 113 and 118 and by those at sites 86, 90 and 118 and 295, respectively, becomes indispensable. Then, all critical mutations that generated the λmax of a SWS1 pigment can be identified by establishing that 1) the difference between the λmax of the ancestral pigment with these mutations and that of the present-day pigment is small (3 ~ 5 nm, depending on the entire λmax-shift) and 2) the difference between the corresponding A/B ratios is < 0.002. Molecular adaptation has been studied mostly by using comparative sequence analyses. These statistical results provide biological hypotheses and need to be tested using experimental means. This is an opportune time to explore the currently available and new genetic systems and test these statistical hypotheses. Evaluating the λmaxs and A/B ratios of mutagenized present-day and their ancestral pigments, we now have a method to identify all critical mutations that are responsible for phenotypic adaptation of SWS1 pigments. The result also explains spectral tuning of the same pigments, a central unanswered question in phototransduction.

  8. A comparison of ultra-endurance cyclists in a qualifying ultra-cycling race for Paris-Brest-Paris and Race Across America-Swiss cycling marathon.

    Science.gov (United States)

    Knechtle, Beat; Wirth, Andrea; Knechtle, Patrizia; Rüst, Christoph Alexander; Rosemann, Thomas

    2012-02-01

    Ultra-endurance events test the adaptation of human physiology to extreme physical and mental demands, high levels of training, motivation, and physical conditioning among participants. To understand basic differences among participants according to the severity of the race, participants in qualifying events for two ultra-endurance cycling races, differing in length and intensity, were compared on measures of anthropometry, training, and support. One race was four times longer, required supporting teams, and racers typically had little sleep, which should lead to the qualifiers being substantially more highly trained than those from the shorter race. The qualifiers in the longer race had greater intensity in training while the qualifiers in the shorter race relied more on training volume. Different strategies and types of training reflected the different demands of the races. Future studies should evaluate personality and motivational differences in ultra-endurance events and between these athletes and athletes in other sports.

  9. Ultra-high energy particle collisions in a regular spacetime without blackholes or naked singularities

    CERN Document Server

    Patil, Mandar

    2012-01-01

    We investigate here the particle acceleration and collisions with extremely large center of mass energies in a perfectly regular spacetime containing neither singularity nor an event horizon. The ultra-high energy collisions of particles near the event horizon of extremal Kerr blackhole, and also in many other examples of extremal blackholes have been investigated and reported recently. We studied an analogous particle acceleration process in the Kerr and Reissner- Nordstrom spacetimes without horizon, containing naked singularities. Further to this, we show here that the particle acceleration and collision process is in fact independent of blackholes and naked singularities, and can happen in a fully regular spacetime containing neither of these. We derive the conditions on the general static spherically symmetric metric for such a phenomena to happen. We show that in order to have ultra-high energy collisions it is necessary for the norm of the timelike Killing vector to admit a maximum with a vanishingly s...

  10. Extremal surface barriers

    Energy Technology Data Exchange (ETDEWEB)

    Engelhardt, Netta; Wall, Aron C. [Department of Physics, University of California,Santa Barbara, CA 93106 (United States)

    2014-03-13

    We present a generic condition for Lorentzian manifolds to have a barrier that limits the reach of boundary-anchored extremal surfaces of arbitrary dimension. We show that any surface with nonpositive extrinsic curvature is a barrier, in the sense that extremal surfaces cannot be continuously deformed past it. Furthermore, the outermost barrier surface has nonnegative extrinsic curvature. Under certain conditions, we show that the existence of trapped surfaces implies a barrier, and conversely. In the context of AdS/CFT, these barriers imply that it is impossible to reconstruct the entire bulk using extremal surfaces. We comment on the implications for the firewall controversy.

  11. Analysis of extreme events

    CSIR Research Space (South Africa)

    Khuluse, S

    2009-04-01

    Full Text Available ) determination of the distribution of the damage and (iii) preparation of products that enable prediction of future risk events. The methodology provided by extreme value theory can also be a powerful tool in risk analysis...

  12. Extreme environments and exobiology.

    Science.gov (United States)

    Friedmann, E I

    1993-01-01

    Ecological research on extreme environments can be applied to exobiological problems such as the question of life on Mars. If life forms (fossil or extant) are found on Mars, their study will help to solve fundamental questions about the nature of life on Earth. Extreme environments that are beyond the range of adaptability of their inhabitants are defined as "absolute extreme". Such environments can serve as terrestrial models for the last stages of life in the history of Mars, when the surface cooled down and atmosphere and water disappeared. The cryptoendolithic microbial community in porous rocks of the Ross Desert in Antarctica and the microbial mats at the bottom of frozen Antarctic lakes are such examples. The microbial communities of Siberian permafrost show that, in frozen but stable communities, long-term survival is possible. In the context of terraforming Mars, selected microorganisms isolated from absolute extreme environments are considered for use in creation of a biological carbon cycle.

  13. Venous Ultrasound (Extremities)

    Science.gov (United States)

    ... News Physician Resources Professions Site Index A-Z Ultrasound - Venous (Extremities) Venous ultrasound uses sound waves to ... limitations of Venous Ultrasound Imaging? What is Venous Ultrasound Imaging? Ultrasound is safe and painless, and produces ...

  14. Statistics of extremes

    CERN Document Server

    Gumbel, E J

    2012-01-01

    This classic text covers order statistics and their exceedances; exact distribution of extremes; the 1st asymptotic distribution; uses of the 1st, 2nd, and 3rd asymptotes; more. 1958 edition. Includes 44 tables and 97 graphs.

  15. Multi-Objective Optimization of A Semisubmersible for Ultra-Deep Water

    Institute of Scientific and Technical Information of China (English)

    CHEN Xin-quan; TAN Jia-hua

    2008-01-01

    Semisubmersible will work well when oil exploitation goes to ultra-deep water because of its variable load capacities, and good motion performance in extreme waves. It is considered to be a main type of platform while the water depth is more than 3000 meters. This paper establishes a multi-objective optimization model of semisubmersible for ultra-deep water, and it is solved by a multi-objective genetic algorithm-NSGA-II. The model is applied to a practical design, and Pareto results are obtained. The effectiveness of the method is verified by hydrodynamic analysis.

  16. Synthesis of CdSe quantum dots with luminescence in the violet region of the solar spectrum.

    Science.gov (United States)

    Shukla, Nisha; Nigra, Michael M

    2010-01-01

    We have designed a simple, one-step synthesis of CdSe quantum dots with photoluminescence frequencies ranging from the red through to the violet region of the solar spectrum. The photoluminescence peaks have FWHM of 30 nm indicating absorption over a narrow range of wavelengths. The effect of solvent type and solvent boiling point on the physical and photoluminescence properties of the quantum dots has been studied. High boiling point, non-polar solvents shift the photoluminescence peak to longer wavelengths and low boiling point, polar solvents shift the photoluminescence peak to shorter wavelengths.

  17. Micelles entrapped Cresyl Violet can selectively detect copper and mercury ions in solution: A fluorescence Correlation Spectroscopy investigation

    Science.gov (United States)

    Das, Nirmal Kumar; Ghosh, Subhadip; Jaiswal, Sunidhi; Tewary, Anu; Mukherjee, Saptarshi

    2017-08-01

    The dynamic interaction of Cresyl Violet (CV) in different micellar systems has been demonstrated in single molecular level by FCS studies. The SDS micelle entrapped CV efficiently detected Cu2+ ions in solution with a limit of detection (LOD) of 70 nM, which is further substantiated with the gradual enhancement of the translational motion. The CV entrapped in the DTAB micelles could selectively detect Hg2+ ions in solution with a LOD of 35 nM. The micelle encapsulated CV was effective in detecting these metal ions in real water samples from different sources.

  18. Multicenter evaluation of crystal violet decolorization assay (CVDA) for rapid detection of isoniazid and rifampicin resistance in Mycobacterium tuberculosis

    OpenAIRE

    Coban, Ahmet Yilmaz; Akbal,Ahmet Ugur; Bicmen, Can; Albay, Ali; Ali Korhan Sig; Uzun, Meltem; Selale, Deniz Sertel; Ozkutuk, Nuri; Surucuoglu, Suheyla; Albayrak, Nurhan; Ucarman, Nilay; Ozkutuk, Aydan; ESEN, Nuran; Ceyhan,Ismail; Ozyurt, Mustafa

    2016-01-01

    The aim of this multicenter study was to evaluate the performance of the crystal violet decolorization assay (CVDA) for detection of multidrug resistant tuberculosis (MDR-TB). This study was performed in 11 centers in two phases. A total of 156 isolates were tested for INH and RIF resistance. In the phase I, 106 clinical isolates were tested in the Center 1–7. In the phase 2, 156 clinical isolates were tested in the center 1–6, center 8–11. Eighty six of 156 tested isolates were the same in p...

  19. Extreme Programming: Maestro Style

    Science.gov (United States)

    Norris, Jeffrey; Fox, Jason; Rabe, Kenneth; Shu, I-Hsiang; Powell, Mark

    2009-01-01

    "Extreme Programming: Maestro Style" is the name of a computer programming methodology that has evolved as a custom version of a methodology, called extreme programming that has been practiced in the software industry since the late 1990s. The name of this version reflects its origin in the work of the Maestro team at NASA's Jet Propulsion Laboratory that develops software for Mars exploration missions. Extreme programming is oriented toward agile development of software resting on values of simplicity, communication, testing, and aggressiveness. Extreme programming involves use of methods of rapidly building and disseminating institutional knowledge among members of a computer-programming team to give all the members a shared view that matches the view of the customers for whom the software system is to be developed. Extreme programming includes frequent planning by programmers in collaboration with customers, continually examining and rewriting code in striving for the simplest workable software designs, a system metaphor (basically, an abstraction of the system that provides easy-to-remember software-naming conventions and insight into the architecture of the system), programmers working in pairs, adherence to a set of coding standards, collaboration of customers and programmers, frequent verbal communication, frequent releases of software in small increments of development, repeated testing of the developmental software by both programmers and customers, and continuous interaction between the team and the customers. The environment in which the Maestro team works requires the team to quickly adapt to changing needs of its customers. In addition, the team cannot afford to accept unnecessary development risk. Extreme programming enables the Maestro team to remain agile and provide high-quality software and service to its customers. However, several factors in the Maestro environment have made it necessary to modify some of the conventional extreme

  20. Statistics of Extremes

    KAUST Repository

    Davison, Anthony C.

    2015-04-10

    Statistics of extremes concerns inference for rare events. Often the events have never yet been observed, and their probabilities must therefore be estimated by extrapolation of tail models fitted to available data. Because data concerning the event of interest may be very limited, efficient methods of inference play an important role. This article reviews this domain, emphasizing current research topics. We first sketch the classical theory of extremes for maxima and threshold exceedances of stationary series. We then review multivariate theory, distinguishing asymptotic independence and dependence models, followed by a description of models for spatial and spatiotemporal extreme events. Finally, we discuss inference and describe two applications. Animations illustrate some of the main ideas. © 2015 by Annual Reviews. All rights reserved.

  1. Extremely deformable structures

    CERN Document Server

    2015-01-01

    Recently, a new research stimulus has derived from the observation that soft structures, such as biological systems, but also rubber and gel, may work in a post critical regime, where elastic elements are subject to extreme deformations, though still exhibiting excellent mechanical performances. This is the realm of ‘extreme mechanics’, to which this book is addressed. The possibility of exploiting highly deformable structures opens new and unexpected technological possibilities. In particular, the challenge is the design of deformable and bi-stable mechanisms which can reach superior mechanical performances and can have a strong impact on several high-tech applications, including stretchable electronics, nanotube serpentines, deployable structures for aerospace engineering, cable deployment in the ocean, but also sensors and flexible actuators and vibration absorbers. Readers are introduced to a variety of interrelated topics involving the mechanics of extremely deformable structures, with emphasis on ...

  2. Precursors of extreme increments

    CERN Document Server

    Hallerberg, S; Holstein, D; Kantz, H; Hallerberg, Sarah; Altmann, Eduardo G.; Holstein, Detlef; Kantz, Holger

    2006-01-01

    We investigate precursors and predictability of extreme events in time series, which consist in large increments within successive time steps. In order to understand the predictability of this class of extreme events, we study analytically the prediction of extreme increments in AR(1)-processes. The resulting strategies are then applied to predict sudden increases in wind speed recordings. In both cases we evaluate the success of predictions via creating receiver operator characteristics (ROC-plots). Surprisingly, we obtain better ROC-plots for completely uncorrelated Gaussian random numbers than for AR(1)-correlated data. Furthermore, we observe an increase of predictability with increasing event size. Both effects can be understood by using the likelihood ratio as a summary index for smooth ROC-curves.

  3. Ultra-High Temperature Gratings

    Institute of Scientific and Technical Information of China (English)

    John Canning; Somnath Bandyopadhyay; Michael Stevenson; Kevin Cook

    2008-01-01

    Regenerated gratings seeded by type-Ⅰ gratings are shown to withstand temperatures beyond 1000 ℃. The method of regeneration offers a new approach to increasing temperature resistance of stable fibre Bragg and other gratings. These ultra-high temperature (UHT) gratings extend the applicability of silicate based components to high temperature applications such as monitoring of smelters and vehicle and aircraft engines to high power fibre lasers.

  4. Weather and Climate Extremes.

    Science.gov (United States)

    1997-09-01

    Antarctica’s highest (New Zealand Antarctic Society, 1974). This extreme exceeded the record of 58°F (14.4°C) that occurred on 20 October 1956 at Esperanza ... Esperanza (also known as Bahia Esperanza , Hope Bay) was in operation from 1945 through the early 1960s. Meteorological/Climatological Factors: This extreme...cm) Location: Grand Ilet, La R’eunion Island [21°00’S, 55°30’E] Date: 26 January 1980 WORLD’S GREATEST 24-HOUR RAINFALL 72 in (182.5 cm

  5. Adventure and Extreme Sports.

    Science.gov (United States)

    Gomez, Andrew Thomas; Rao, Ashwin

    2016-03-01

    Adventure and extreme sports often involve unpredictable and inhospitable environments, high velocities, and stunts. These activities vary widely and include sports like BASE jumping, snowboarding, kayaking, and surfing. Increasing interest and participation in adventure and extreme sports warrants understanding by clinicians to facilitate prevention, identification, and treatment of injuries unique to each sport. This article covers alpine skiing and snowboarding, skateboarding, surfing, bungee jumping, BASE jumping, and whitewater sports with emphasis on epidemiology, demographics, general injury mechanisms, specific injuries, chronic injuries, fatality data, and prevention. Overall, most injuries are related to overuse, trauma, and environmental or microbial exposure.

  6. Extremal graph theory

    CERN Document Server

    Bollobas, Bela

    2004-01-01

    The ever-expanding field of extremal graph theory encompasses a diverse array of problem-solving methods, including applications to economics, computer science, and optimization theory. This volume, based on a series of lectures delivered to graduate students at the University of Cambridge, presents a concise yet comprehensive treatment of extremal graph theory.Unlike most graph theory treatises, this text features complete proofs for almost all of its results. Further insights into theory are provided by the numerous exercises of varying degrees of difficulty that accompany each chapter. A

  7. Challenges in optics for Extremely Large Telescope instrumentation

    CERN Document Server

    Span`o, P; Norrie, C J; Cunningham, C R; Strassmeier, K G; Bianco, A; Blanche, P A; Bougoin, M; Ghigo, M; Hartmann, P; Zago, L; Atad-Ettedgui, E; Delabre, B; Dekker, H; Melozzi, M; Snyders, B; Takke, R; Walker, D D

    2006-01-01

    We describe and summarize the optical challenges for future instrumentation for Extremely Large Telescopes (ELTs). Knowing the complex instrumental requirements is crucial for the successful design of 30-60m aperture telescopes. After all, the success of ELTs will heavily rely on its instrumentation and this, in turn, will depend on the ability to produce large and ultra-precise optical components like light-weight mirrors, aspheric lenses, segmented filters, and large gratings. New materials and manufacturing processes are currently under study, both at research institutes and in industry. In the present paper, we report on its progress with particular emphasize on volume-phase-holographic gratings, photochromic materials, sintered silicon-carbide mirrors, ion-beam figuring, ultra-precision surfaces, and free-form optics. All are promising technologies opening new degrees of freedom to optical designers. New optronic-mechanical systems will enable efficient use of the very large focal planes. We also provide...

  8. Blue-violet light irradiation dose dependently decreases carotenoids in human skin, which indicates the generation of free radicals.

    Science.gov (United States)

    Vandersee, Staffan; Beyer, Marc; Lademann, Juergen; Darvin, Maxim E

    2015-01-01

    In contrast to ultraviolet and infrared irradiation, which are known to facilitate cutaneous photoaging, immunosuppression, or tumour emergence due to formation of free radicals and reactive oxygen species, potentially similar effects of visible light on the human skin are still poorly characterized. Using a blue-violet light irradiation source and aiming to characterize its potential influence on the antioxidant status of the human skin, the cutaneous carotenoid concentration was measured noninvasively in nine healthy volunteers using resonance Raman spectroscopy following irradiation. The dose-dependent significant degradation of carotenoids was measured to be 13.5% and 21.2% directly after irradiation at 50 J/cm² and 100 J/cm² (P skin. In all volunteers the cutaneous carotenoid concentration dropped down in a manner similar to that caused by the infrared or ultraviolet irradiations, leading to the conclusion that also blue-violet light at high doses could represent a comparably adverse factor for human skin.

  9. Evaluation of crystal violet decolorization assay for minimal inhibitory concentration detection of primary antituberculosis drugs against Mycobacterium tuberculosis isolates

    Directory of Open Access Journals (Sweden)

    Ahmet Yilmaz Coban

    2016-01-01

    Full Text Available In this study we evaluated the crystal violet decolorization assay (CVDA for detection of minimum inhibitory concentration (MIC of antituberculosis drugs. 53 isolates were tested in this study and 13 of them were multidrug resistant (MDR isolates. The antibiotics concentrations were 2-0.06 mg/L for isoniazid (INH and rifampicin (RIF and were 16-0.25 mg/L for streptomycin (STM and ethambutol (EMB. Crystal violet (CV-25 mg/L was added into the microwells on the seventh day of incubation and incubation was continued until decolorization. Decolorization of CV was the predictor of bacterial growth. Overall agreements for four drugs were detected as 98.1%, and the average time was detected as 9.5 ± 0.89 day after inoculation. One isolate for INH and two isolates for STM were determined resistant in the reference method, but susceptible by the CVDA. One isolate was susceptible to EMB by the reference method, but resistant by the CVDA. All results were concordant for RIF. This study shows that CVDA is a rapid, reliable and suitable for determination of MIC values of Mycobacterium tuberculosis. And it can be used easily especially in countries with limited-sources.

  10. Spectrally-isolated violet to blue wavelength generation by cascaded degenerate four-wave mixing in a photonic crystal fiber.

    Science.gov (United States)

    Yuan, Jinhui; Kang, Zhe; Li, Feng; Zhang, Xianting; Zhou, Guiyao; Sang, Xinzhu; Wu, Qiang; Yan, Binbin; Zhou, Xian; Wang, Liang; Zhong, Kangping; Wang, Kuiru; Yu, Chongxiu; Tam, Hwa Yaw; Wai, P K A

    2016-06-01

    Generation of spectrally-isolated wavelengths in the violet to blue region based on cascaded degenerate four-wave mixing (FWM) is experimentally demonstrated for the first time in a tailor-made photonic crystal fiber, which has two adjacent zero dispersion wavelengths (ZDWs) at 696 and 852 nm in the fundamental mode. The influences of the wavelength λp and the input average power Pav of the femtosecond pump pulses on the phase-matched frequency conversion process are studied. When femtosecond pump pulses at λp of 880, 870, and 860 nm and Pav of 500 mW are coupled into the normal dispersion region close to the second ZDW, the first anti-Stokes waves generated near the first ZDW act as a secondary pump for the next FWM process. The conversion efficiency ηas2 of the second anti-Stokes waves, which are generated at the violet to blue wavelengths of 430, 456, and 472 nm, are 4.8, 6.48, and 9.66%, for λp equalling 880, 870, and 860 nm, respectively.

  11. Over 1000 mW single mode operation of planar inner stripe blue-violet laser diodes

    Energy Technology Data Exchange (ETDEWEB)

    Sasaoka, C.; Fukuda, K.; Ohya, M.; Shiba, K.; Sumino, M.; Kohmoto, S.; Naniwae, K.; Matsudate, M.; Mizuki, E.; Masumoto, I.; Kobayashi, R.; Kudo, K.; Sasaki, T.; Nishi, K. [System Devices Research Laboratories, NEC Corporation, 9-1, Seiran 2-chome, Otsu, Shiga 520-0833 (Japan)

    2006-05-15

    We report the 1000 mW single mode operation of a planar blue-violet laser diode with inner stripe waveguide. Kink-free output surpassed 400 mW (CW) and 600 mW (50 ns pulsed, duty 50%) at temperatures up to 90 C. Precise optical field design for narrow stripe waveguide as well as damage-free stripe formation was a key to achieving watt class output. By utilizing buried AlN as optical and current confinement layers, a damage-free inner stripe as narrow as 1.0 {mu}m wide was successfully fabricated. Planar inner stripe structure also has the advantage of a small increase in the electrical resistance for such a narrow stripe, which is favorable for high power operations. The results here indicate the potential of this planar blue-violet laser diode for high power applications as the next generation of optical disc systems. (copyright 2006 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Solving the 170-Year-Old Mystery About Red-Violet and Blue Transient Intermediates in the Gmelin Reaction.

    Science.gov (United States)

    Gao, Yin; Toubaei, Abouzar; Kong, Xianqi; Wu, Gang

    2015-11-23

    The Gmelin reaction between nitroprusside and sulfides in aqueous solution is known to produce two transient intermediates with distinct colors: an initial red-violet intermediate that subsequently converts into a blue intermediate. In this work, we use a combination of multinuclear ((17) O, (15) N, (13) C) NMR, UV/Vis, IR spectroscopic techniques and quantum chemical computation to show unequivocally that the red-violet intermediate is [Fe(CN)5 N(O)S](4-) and the blue intermediate is [Fe(CN)5 N(O)SS)](4-) . While the formation of [Fe(CN)5 N(O)S](4-) has long been postulated in the literature, this study provides the most direct proof of its structure. In contrast, [Fe(CN)5 N(O)SS)](4-) represents the first example of any metal coordination complex containing a perthionitro ligand. The new reaction pathways found in this study not only provide clues for the mode of action of nitroprusside for its pharmacological activity, but also have broader implications to the biological role of H2 S, potential reactions between H2 S and nitric oxide donor compounds, and the possible biological function of polysulfides.

  13. Efficient photodegradation of methyl violet dye using TiO2/Pt and TiO2/Pd photocatalysts

    Science.gov (United States)

    Saeed, Khalid; Khan, Idrees; Gul, Tamanna; Sadiq, Mohammad

    2017-02-01

    Titanium oxide supported palladium (TiO2/Pd) and titanium oxide supported platinum (TiO2/Pt) nanoparticles were prepared from their precursors through the incipient wetness method. The TiO2/Pd and TiO2/Pt nanoparticles were characterized by scanning electron microscopy (SEM), and energy dispersive X-rays (EDX), while the photodegradation study of methyl violet was performed by UV/VIS spectrophotometry. The morphological study shows that the Pd and Pt were well deposited on the surface of TiO2, which was confirmed by EDX. Both TiO2/Pd and TiO2/Pt nanoparticles were used as photocatalysts for the photodegradation of methyl violet in aqueous media under UV-light irradiation. The photodegradation study revealed that the TiO2/Pd and TiO2/Pt nanoparticles degraded about 95 and 78% of dye within 20 min, respectively. The effect of various parameters such as catalyst dosage, concentration of dye, and medium on the photocatalytic degradation was examined. The activity of recovered TiO2/Pd and TiO2/Pt nanoparticles was studied.

  14. Blue-Violet Light Irradiation Dose Dependently Decreases Carotenoids in Human Skin, Which Indicates the Generation of Free Radicals

    Directory of Open Access Journals (Sweden)

    Staffan Vandersee

    2015-01-01

    Full Text Available In contrast to ultraviolet and infrared irradiation, which are known to facilitate cutaneous photoaging, immunosuppression, or tumour emergence due to formation of free radicals and reactive oxygen species, potentially similar effects of visible light on the human skin are still poorly characterized. Using a blue-violet light irradiation source and aiming to characterize its potential influence on the antioxidant status of the human skin, the cutaneous carotenoid concentration was measured noninvasively in nine healthy volunteers using resonance Raman spectroscopy following irradiation. The dose-dependent significant degradation of carotenoids was measured to be 13.5% and 21.2% directly after irradiation at 50 J/cm² and 100 J/cm² (P<0.05. The irradiation intensity was 100 mW/cm². This is above natural conditions; the achieved doses, though, are acquirable under natural conditions. The corresponding restoration lasted 2 and 24 hours, respectively. The degradation of cutaneous carotenoids indirectly shows the amount of generated free radicals and especially reactive oxygen species in human skin. In all volunteers the cutaneous carotenoid concentration dropped down in a manner similar to that caused by the infrared or ultraviolet irradiations, leading to the conclusion that also blue-violet light at high doses could represent a comparably adverse factor for human skin.

  15. Highly sensitive UVA and violet photodetector based on single-layer graphene-TiOsub>2sub> heterojunction.

    Science.gov (United States)

    Liang, Feng-Xia; Zhang, Deng-Yue; Wang, Jiu-Zhen; Kong, Wei-Yu; Zhang, Zhi-Xiang; Wang, Yi; Luo, Lin-Bao

    2016-11-14

    A highly sensitive ultraviolet A (UVA) and violet photodetector based on p-type single-layer graphene (SLG)-TiOsub>2sub> heterostructure was fabricated by transferring chemical vapor deposition derived SLG on the surface of commercial single-crystal TiOsub>2sub> wafer. Optoelectronic analysis reveals the as-fabricated Schottky junction PD was highly sensitive to light illumination in UVA and violet range, with peak sensitivity at 410 nm and excellent stability and reproducibility, but virtually blind to illumination with wavelength less than 350 nm or more than 460 nm. The on/off ratio of the device was calculated to be 6.8 × 104, which is better than the majority of previously reported TiOsub>2sub> based PDs. What is more, the rise/fall time were estimated to be 0.74/1.18 ms, much faster than other TiOsub>2sub> based counterparts. The totality of the above result signifies that the present SLG-TiOsub>2sub> Schottky junction photodetector may have promising application in future high-speed, high-sensitivity optoelectronic nanodevices and systems.

  16. Synthesis and photoluminescence of violet-blue phosphor Ba10(PO4)6F2: Eu2+

    Science.gov (United States)

    Huang, Yumei; Zhang, Xinguo; Pan, Jialiang

    2017-01-01

    A violet-blue phosphor of Ba10(PO4)6F2: Eu2+ was prepared by high-temperature solid state reaction. Luminescence, concentration quenching and thermal stability of Ba10(PO4)6F2: Eu2+ are systematically investigated. The phosphor exhibits a broadband UV absorption and a violet-blue emission peaking at 420 nm with corresponding CIE coordinates of (0.163, 0.024). It is found that Eu2+ ions occupy 9-coordinated Ba(1) and 7-coordinated Ba(2) site in Ba10(PO4)6F2, and therefore generate two emission sub-bands at 415 and 433 nm. The optimal concentration of Eu2+ is 5 mol% according to emission intensity and the quenching mechanism is verified to be a dipole-dipole interaction. Ba10(PO4)6F2: 0.05Eu2+ phosphor shows good thermal stability with 81% of room temperature intensity at 180 °C.

  17. The relationship between the violet pigment PP-V production and intracellular ammonium level in Penicillium purpurogenum.

    Science.gov (United States)

    Kojima, Ryo; Arai, Teppei; Matsufuji, Hiroshi; Kasumi, Takafumi; Watanabe, Taisuke; Ogihara, Jun

    2016-12-01

    Penicillium purpurogenum is the fungus that produces an azaphilone pigment. However, details about the pigment biosynthesis pathway are unknown. The violet pigment PP-V is the one of the main pigments biosynthesized by this fungus. This pigment contains an amino group in a pyran ring as its core structure. We focused on this pigment and examined the relationship between intracellular ammonium concentration and pigment production using glutamine as a nitrogen source. The intracellular ammonium level decreased about 1.5-fold in conditions favoring PP-V production. Moreover, P. purpurogenum was transferred to medium in which it commonly produces the related pigment PP-O after cultivating it in the presence or absence of glutamine to investigate whether this fungus biosynthesizes PP-V using surplus ammonium in cells. Only mycelia cultured in medium containing 10 mM glutamine produced the violet pigment, and simultaneously intracellular ammonium levels decreased under this condition. From comparisons of the amount of PP-V that was secreted with quantity of surplus intracellular ammonium, it is suggested that P. purpurogenum maintains ammonium homeostasis by excreting waste ammonium as PP-V.

  18. Exposure to Crystal Violet, Its Toxic, Genotoxic and Carcinogenic Effects on Environment and Its Degradation and Detoxification for Environmental Safety.

    Science.gov (United States)

    Mani, Sujata; Bharagava, Ram Naresh

    2016-01-01

    Crystal Violet (CV), a triphenylmethane dye, has been extensively used in human and veterinary medicine as a biological stain, as a textile dye in textile processing industries and also used to provide a deep violet color to paints and printing ink. CV is also used as a mutagenic and bacteriostatic agent in medical solutions and antimicrobial agent to prevent the fungal growth in poultry feed. Inspite of its many uses, CV has been reported as a recalcitrant dye molecule that persists in environment for a long period and pose toxic effects in environment. It acts as a mitotic poison, potent carcinogen and a potent clastogene promoting tumor growth in some species of fish. Thus, CV is regarded as a biohazard substance. Although, there are several physico-chemical methods such as adsorption, coagulation and ion-pair extraction reported for the removal of CV, but these methods are insufficient for the complete removal of CV from industrial wastewaters and also produce large quantity of sludge containing secondary pollutants. However, biological methods are regarded as cost-effective and eco-friendly for the treatment of industrial wastewaters, but these methods also have certain limitations. Therefore, there is an urgent need to develop such eco-friendly and cost-effective biological treatment methods, which can effectively remove the dye from industrial wastewaters for the safety of environment, as well as human and animal health.

  19. Adsorption of Acid Yellow-73 and Direct Violet-51 Dyes from Textile Wastewater by Using Iron Doped Corncob Charcoal

    Directory of Open Access Journals (Sweden)

    Mujtaba Baqar

    2015-06-01

    Full Text Available The presence of synthetic dyes in textile industry wastewater lead to deterioration of precious fresh water resources, making the need to remove dyes crucial for environmental protection. Recently, different techniques have been employed to remove these dyes from water resources. Among them, biosorption has gained tremendous popularity due to its eco-friendly nature and inexpensive method. In this study, the removal potential of two acid dyes, i.e. yellow-73 and direct violet-51, was assessed from textile effluent samples using iron modified corncob charcoal. The adsorption efficiency ranged between 93.93 ­ 97.96 % and 92.2 - 95.4 % for acid yellow-73 and direct violet-51, respectively. Furthermore, study highlights optimum parameters for successful adsorption of these dyes, such as stirring time (numbers, pH (numbers, temperature (numbers, and adsorbent dosage (numbers. Keeping in consideration these findings, we recommend the use of Iron Doped Corncob Charcoal (IDCC as a low-cost, efficient alternative for wastewater treatment, primarily minimizing the detrimental effects of hazardous dyes.

  20. Using violet laser-induced chlorophyll fluorescence emission spectra for crop yield assessment of cowpea (Vigna unguiculata (L) Walp) varieties

    Science.gov (United States)

    Anderson, Benjamin; Buah-Bassuah, Paul K.; Tetteh, Jonathan P.

    2004-07-01

    The use of violet laser-induced chlorophyll fluorescence (LICF) emission spectra to monitor the growth of five varieties of cowpea in the University of Cape Coast Botanical Garden is presented. Radiation from a continuous-wave violet laser diode emitting at 396 nm through a fibre is closely incident on in vivo leaves of cowpea to excite chlorophyll fluorescence, which is detected by an integrated spectrometer with CCD readout. The chlorophyll fluorescence spectra with peaks at 683 and 731 nm were used for growth monitoring of the cowpea plants over three weeks and analysed using Gaussian spectral functions with curve fitted parameters to determine the peak positions, area under the spectral curve and the intensity ratio F683/F731. The variation in the intensity ratio of the chlorophyll bands showed sensitive changes indicating the photosynthetic activity of the cowpea varieties. A discussion of the fluorescence result as compared to conventional assessment is presented with regard to discrimination between the cowpea varieties in terms of crop yield performance.

  1. Assessment of adsorption kinetics for removal potential of Crystal Violet dye from aqueous solutions using Moroccan pyrophyllite

    Directory of Open Access Journals (Sweden)

    Youssef Miyah

    2017-06-01

    Full Text Available This study involves the adsorption of Crystal Violet (CV dye adsorbed from solution on the pyrophyllite’s surface. The batch technique was used under a variety of conditions to produce quantitative adsorption, namely amount of adsorbent, dye concentration, contact time, pH solution and temperature. The maximum adsorption capacity of Crystal Violet on pyrophyllite was 9.58 mg/g for 10 mg/L of CV concentration, pH = 6.8 at a temperature 20 °C and 1 g/L of adsorbent. This study of adsorption kinetics was carried out within framework of three models: intraparticle diffusion, pseudo-first order and pseudo-second order. The experimental isotherm data were analyzed using Langmuir and Freundlich models. Different thermodynamic parameters have shown spontaneous reaction with endothermic nature (The estimated value for ΔG was −7.64 kJ/mol at 293 K. Various techniques for characterizing the adsorbent were applied including X-ray diffraction (XRD, X-ray fluorescence spectroscopy (XRF, scanning electron microscopy (SEM and transmission electron microscopy (TEM coupled by energy dispersive X-ray spectroscopy (EDX. In addition, the regenerated adsorbents technique was reused several times; this demonstrated an economical aspect of using pyrophyllite which underlines the re-use importance considering the material capacity to regenerate.

  2. Extremity perfusion for sarcoma

    NARCIS (Netherlands)

    Hoekstra, Harald Joan

    2008-01-01

    For more than 50 years, the technique of extremity perfusion has been explored in the limb salvage treatment of local, recurrent, and multifocal sarcomas. The "discovery" of tumor necrosis factor-or. in combination with melphalan was a real breakthrough in the treatment of primarily irresectable ext

  3. Hydrological extremes and security

    Science.gov (United States)

    Kundzewicz, Z. W.; Matczak, P.

    2015-04-01

    Economic losses caused by hydrological extremes - floods and droughts - have been on the rise. Hydrological extremes jeopardize human security and impact on societal livelihood and welfare. Security can be generally understood as freedom from threat and the ability of societies to maintain their independent identity and their functional integrity against forces of change. Several dimensions of security are reviewed in the context of hydrological extremes. The traditional interpretation of security, focused on the state military capabilities, has been replaced by a wider understanding, including economic, societal and environmental aspects that get increasing attention. Floods and droughts pose a burden and serious challenges to the state that is responsible for sustaining economic development, and societal and environmental security. The latter can be regarded as the maintenance of ecosystem services, on which a society depends. An important part of it is water security, which can be defined as the availability of an adequate quantity and quality of water for health, livelihoods, ecosystems and production, coupled with an acceptable level of water-related risks to people, environments and economies. Security concerns arise because, over large areas, hydrological extremes - floods and droughts - are becoming more frequent and more severe. In terms of dealing with water-related risks, climate change can increase uncertainties, which makes the state's task to deliver security more difficult and more expensive. However, changes in population size and development, and level of protection, drive exposure to hydrological hazards.

  4. Acute lower extremity ischaemia

    African Journals Online (AJOL)

    tend to impact at arterial bifurcations, the commonest site being the ... Other ominous signs of advanced ischaemia include bluish ... Recommended standards for lower extremity ischaemia*. Doppler signals ... of the embolectomy procedure. An ... in a cath-lab or angio-suite under local ... We serially measure the aPTT and.

  5. Extremity perfusion for sarcoma

    NARCIS (Netherlands)

    Hoekstra, Harald Joan

    2008-01-01

    For more than 50 years, the technique of extremity perfusion has been explored in the limb salvage treatment of local, recurrent, and multifocal sarcomas. The "discovery" of tumor necrosis factor-or. in combination with melphalan was a real breakthrough in the treatment of primarily irresectable

  6. Statistics of Local Extremes

    DEFF Research Database (Denmark)

    Larsen, Gunner Chr.; Bierbooms, W.; Hansen, Kurt Schaldemose

    2003-01-01

    . A theoretical expression for the probability density function associated with local extremes of a stochasticprocess is presented. The expression is basically based on the lower four statistical moments and a bandwidth parameter. The theoretical expression is subsequently verified by comparison with simulated...

  7. de Sitter Extremal Surfaces

    CERN Document Server

    Narayan, K

    2015-01-01

    We study extremal surfaces in de Sitter space in the Poincare slicing in the upper patch, anchored on spatial subregions at the future boundary ${\\cal I}^+$, restricted to constant boundary Euclidean time slices (focussing on strip subregions). We find real extremal surfaces of minimal area as the boundaries of past lightcone wedges of the subregions in question: these are null surfaces with vanishing area. We find also complex extremal surfaces as complex extrema of the area functional, and the area is not always real-valued. In $dS_4$ the area is real and has some structural resemblance with entanglement entropy in a dual $CFT_3$. There are parallels with analytic continuation from the Ryu-Takayanagi expressions for holographic entanglement entropy in $AdS$. We also discuss extremal surfaces in the $dS$ black brane and the de Sitter "bluewall" studied previously. The $dS_4$ black brane complex surfaces exhibit a real finite cutoff-independent extensive piece. In the bluewall geometry, there are real surface...

  8. Moving in extreme environments

    DEFF Research Database (Denmark)

    Lucas, Samuel J E; Helge, Jørn W; Schütz, Uwe H W

    2016-01-01

    and transcontinental races) and expeditions (e.g. polar crossings), to the more gravitationally limited load carriage (e.g. in the military context). Juxtaposed to these circumstances is the extreme metabolic and mechanical unloading associated with space travel, prolonged bedrest and sedentary lifestyle, which may...

  9. 5G Ultra-Dense Cellular Networks

    OpenAIRE

    Ge, Xiaohu; Tu, Song; Mao, Guoqiang; Wang, Cheng-xiang; Han, Tao

    2015-01-01

    Traditional ultra-dense wireless networks are recommended as a complement for cellular networks and are deployed in partial areas, such as hotspot and indoor scenarios. Based on the massive multiple-input multi-output (MIMO) antennas and the millimeter wavecommunication technologies, the 5G ultra-dense cellular network is proposed to deploy in overall cellular scenarios. Moreover, a distribution network architecture is presented for 5G ultra-dense cellular networks. Furthermore, the backhaul ...

  10. Extreme nonlinear optics and laser damage

    Science.gov (United States)

    Maldutis, Evaldas

    2010-11-01

    The study of laser induced damage threshold caused by series of identical laser pulses (LID-T-N) on gamma radiation resistant glasses and their analogs is performed applying know-how ultra stable laser radiation. The presented results and analysis of earlier received results show that nonlinear optical phenomena in extreme conditions of interaction are different from the traditional nonlinear optical processes, because they depend not only on intensity of electromagnetic field of laser radiation, but also on the pulse number in series of identical laser pulses. This range of laser intensities is not wide; it is different for each material and determines the range of Extreme Nonlinear Optics. The dependence of LID-T-N on pulse number N for different kinds of high quality transparent glasses was observed. The study of dynamics of these processes (i.e. the study of dependence on N) at different intensities in series of incident laser pulses provides new information about properties of the materials useful for studying laser damage fundamentals and their application. The expectation that gamma radiation resistant glasses could give useful information for technology of resistant optics for high power lasers has not proved. The received results well correspond with the earlier proposed model of laser damage.

  11. Ultra low emission vehicle development: a study on the drivers for car firms and the implications for sustainable development policy

    NARCIS (Netherlands)

    Dijk, M.; Montalvo Corral, C.

    2009-01-01

    This paper studies the factors that lead automotive manufacturing firms to invest in Ultra Low Emission Vehicles (ULEVs). ULEVs are vehicles that emit extremely low levels of harmful gases compared to other vehicles. In contrast to studies that examine aggregated patterns on the market (such as

  12. Optimal radio window for the detection of ultra-high energy cosmic rays and neutrinos off the Moon

    NARCIS (Netherlands)

    Scholten, O.; Bacelar, J.; Braun, R.; de Bruyn, A. G.; Falcke, H.; Stappers, B.; Strom, R. G.

    2006-01-01

    When high-energy cosmic rays impinge on a dense dielectric medium, radio waves are produced through the Askaryan effect. We show that at wavelengths comparable to the length of the shower produced by an Ultra-High Energy cosmic ray or neutrino, radio signals are ail extremely efficient way to detect

  13. Ultra low emission vehicle development: a study on the drivers for car firms and the implications for sustainable development policy

    NARCIS (Netherlands)

    Dijk, M.; Montalvo Corral, C.

    2009-01-01

    This paper studies the factors that lead automotive manufacturing firms to invest in Ultra Low Emission Vehicles (ULEVs). ULEVs are vehicles that emit extremely low levels of harmful gases compared to other vehicles. In contrast to studies that examine aggregated patterns on the market (such as sale

  14. Study of Volumetrically Heated Ultra-High Energy Density Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Rocca, Jorge J. [Colorado State Univ., Fort Collins, CO (United States)

    2016-10-27

    Heating dense matter to millions of degrees is important for applications, but requires complex and expensive methods. The major goal of the project was to demonstrate using a compact laser the creation of a new ultra-high energy density plasma regime characterized by simultaneous extremely high temperature and high density, and to study it combining experimental measurements and advanced simulations. We have demonstrated that trapping of intense femtosecond laser pulses deep within ordered nanowire arrays can heat near solid density matter into a new ultra hot plasma regime. Extreme electron densities, and temperatures of several tens of million degrees were achieved using laser pulses of only 0.5 J energy from a compact laser. Our x-ray spectra and simulations showed that extremely highly ionized plasma volumes several micrometers in depth are generated by irradiation of gold and Nickel nanowire arrays with femtosecond laser pulses of relativistic intensities. We obtained extraordinarily high degrees of ionization (e.g. we peeled 52 electrons from gold atoms, and up to 26 electrons from nickel atoms). In the process we generated Gigabar pressures only exceeded in the central hot spot of highly compressed thermonuclear fusion plasmas.. The plasma created after the dissolved wires expand, collide, and thermalize, is computed to have a thermal energy density of 0.3 GJ cm-3 and a pressure of 1-2 Gigabar. These are pressures only exceeded in highly compressed thermonuclear fusion plasmas. Scaling these results to higher laser intensities promises to create plasmas with temperatures and pressures exceeding those in the center of the sun.

  15. Non-extremal branes

    Directory of Open Access Journals (Sweden)

    Pablo Bueno

    2015-04-01

    Full Text Available We prove that for arbitrary black brane solutions of generic Supergravities there is an adapted system of variables in which the equations of motion are exactly invariant under electric–magnetic duality, i.e. the interchange of a given extended object by its electromagnetic dual. We obtain thus a procedure to automatically construct the electromagnetic dual of a given brane without needing to solve any further equation. We apply this procedure to construct the non-extremal (p,q-string of Type-IIB String Theory (new in the literature, explicitly showing how the dual (p,q-five-brane automatically arises in this construction. In addition, we prove that the system of variables used is suitable for a generic characterization of every double-extremal Supergravity brane solution, which we perform in full generality.

  16. Tibetans at extreme altitude.

    Science.gov (United States)

    Wu, Tianyi; Li, Shupin; Ward, Michal P

    2005-01-01

    Between 1960 and 2003, 13 Chinese expeditions successfully reached the summit of Chomolungma (Mt Everest or Sagarmatha). Forty-five of the 80 summiteers were Tibetan highlanders. During these and other high-altitude expeditions in Tibet, a series of medical and physiological investigations were carried out on the Tibetan mountaineers. The results suggest that these individuals are better adapted to high altitude and that, at altitude, they have a greater physical capacity than Han (ethnic Chinese) lowland newcomers. They have higher maximal oxygen uptake, greater ventilation, more brisk hypoxic ventilatory responses, larger lung volumes, greater diffusing capacities, and a better quality of sleep. Tibetans also have a lower incidence of acute mountain sickness and less body weight loss. These differences appear to represent genetic adaptations and are obviously significant for humans at extreme altitude. This paper reviews what is known about the physiologic responses of Tibetans at extreme altitudes.

  17. Extremal periodic wave profiles

    Directory of Open Access Journals (Sweden)

    E. van Groesen

    2007-01-01

    Full Text Available As a contribution to deterministic investigations into extreme fluid surface waves, in this paper wave profiles of prescribed period that have maximal crest height will be investigated. As constraints the values of the momentum and energy integrals are used in a simplified description with the KdV model. The result is that at the boundary of the feasible region in the momentum-energy plane, the only possible profiles are the well known cnoidal wave profiles. Inside the feasible region the extremal profiles of maximal crest height are "cornered" cnoidal profiles: cnoidal profiles of larger period, cut-off and periodically continued with the prescribed period so that at the maximal crest height a corner results.

  18. Extremal Hairy Black Holes

    CERN Document Server

    Gonzalez, P A; Saavedra, Joel; Vasquez, Yerko

    2014-01-01

    We consider a gravitating system consisting of a scalar field minimally coupled to gravity with a self-interacting potential and an U(1) electromagnetic field. Solving the coupled Einstein-Maxwell-scalar system we find exact hairy charged black hole solutions with the scalar field regular everywhere. We go to the zero temperature limit and we study the effect of the scalar field on the near horizon geometry of an extremal black hole. We find that except a critical value of the charge of the black hole there is also a critical value of the charge of the scalar field beyond of which the extremal black hole is destabilized. We study the thermodynamics of these solutions and we find that if the space is flat then at low temperature the Reissner-Nordstr\\"om black hole is thermodynamically preferred, while if the space is AdS the hairy charged black hole is thermodynamically preferred at low temperature.

  19. Effect of LOS/NLOS Propagation on 5G Ultra-Dense Networks

    DEFF Research Database (Denmark)

    Galiotto, Carlo; Pratas, Nuno; Doyle, Linda

    2017-01-01

    The combined presence of Line-of-Sight (LOS) and Non-Line-of-Sight (NLOS) components in the radio propagation environment can severely degrade the Ultra-Dense Networks (UDNs) performance. Backed by a stochastic geometry model, we show that when the LOS/NLOS propagation components are taken into a...... and to take advantage of extreme cell densification in the upcoming 5G wireless networks....

  20. GRB 080407: An Ultra-long Burst Discovered by the IPN

    Science.gov (United States)

    Cummings, J; Barthelmy, S.; Gehrels, N.; Krimm, H.; Palmer, D.; Palshin, V.; Hurley, K.; Goldsten, J.; Mitrofanov, I. G.; Boynton, W.; vonKienlln, A.; Feroci, M.; Aptekar, R.; Frederiks, D.; Golenetskli, S.; Mazets, E.; Svinkin, D.; Golovin, D.; Litvak, M. L.; Sanin, A. B.; Fellows, C.; Harshman, K.; Starr, R.; Rau, A.; Zhang, X.

    2012-01-01

    We present observations of the extremely long GRB 080704 obtained with the instruments of the Interplanetary Network (IPN). The observations reveal two distinct emission episodes, separated by a approx.1500 s long period of quiescence. The total burst duration is about 2100 s. We compare the temporal and spectral characteristics of this burst with those obtained for other ultra-long GRBs and discuss these characteristics in the context of different models.

  1. GRB 080407: an ultra-long burst discovered by the IPN

    CERN Document Server

    Pal'shin, V; Goldsten, J; Mitrofanov, I G; Boynton, W; von Kienlin, A; Cummings, J; Feroci, M; Aptekar, R; Frederiks, D; Golenetskii, S; Mazets, E; Svinkin, D; Golovin, D; Litvak, M L; Sanin, A B; Fellows, C; Harshman, K; Starr, R; Rau, A; Savchenko, V; Zhang, X; Barthelmy, S; Gehrels, N; Krimm, H; Palmer, D; Del Monte, E; Marisaldi, M

    2013-01-01

    We present observations of the extremely long GRB 080704 obtained with the instruments of the Interplanetary Network (IPN). The observations reveal two distinct emission episodes, separated by a ~1500 s long period of quiescence. The total burst duration is about 2100 s. We compare the temporal and spectral characteristics of this burst with those obtained for other ultra-long GRBs and discuss these characteristics in the context of different models.

  2. The Work Function Associated with Ultra-relativistic Electron Emission from Strongly Magnetized Neutron Star Surface

    Indian Academy of Sciences (India)

    Arpita Ghosh; Somenath Chakrabarty

    2011-09-01

    Following an extremely interesting idea (Schieber 1984), published long ago, the work function associated with the emission of ultra-relativistic electrons from magnetically deformed metallic crystal (mainly iron) at the outer crust of a magnetar is obtained using relativistic version of Thomas–Fermi type model for electron distribution around the nuclei in this region. In the present scenario, surprisingly, the work function becomes anisotropic; the longitudinal part is an increasing function of magnetic field strength, whereas the transverse part diverges.

  3. Horizontal Shear Transfer Between Ultra High Performance Concrete And Lightweight Concrete

    OpenAIRE

    Banta, Timothy E.

    2005-01-01

    Ultra high performance concrete, specifically Ductal® concrete, has begun to revolutionize the bridge design industry. This extremely high strength material has given smaller composite sections the ability to carry larger loads. As the forces being transferred through composite members are increasing in magnitude, it is vital that the equations being used for design are applicable for use with the new materials. Of particular importance is the design of the horizontal shear reinforcement ...

  4. Religious Extremism in Pakistan

    Science.gov (United States)

    2014-12-01

    Face (July 2008): 32. 21 Ahmed Rashid , Pakistan on the Brink: The Future of America, Pakistan, and Afghanistan (New York: Viking, 2012). 22 Brian J...promoting extremism. Commentators such as Jessica Stern, Alan Richards, Hussain Haqqani, Ahmed Rashid , and Ali Riaz are a few of the scholars who...www.jstor.org/stable/3183558; See also Ahmed Rashid , Descent Into Chaos: The United States and the Failure of Nation Building in Pakistan, Afghanistan, and

  5. USACE Extreme Sea levels

    Science.gov (United States)

    2014-03-14

    report summarising the results of the research, together with a set of recommendations arising from the research. This report describes progress to...Southampton University at HR Wallingford and subsequent teleconference with Heidi Moritz and Kate White. The notes summarising the findings of the...suggestion was made that we may want to begin talking about extreme water levels separate from storms. Ivan mentioned an analysis of storminess which

  6. Extreme geomagnetically induced currents

    Science.gov (United States)

    Kataoka, Ryuho; Ngwira, Chigomezyo

    2016-12-01

    We propose an emergency alert framework for geomagnetically induced currents (GICs), based on the empirically extreme values and theoretical upper limits of the solar wind parameters and of d B/d t, the time derivative of magnetic field variations at ground. We expect this framework to be useful for preparing against extreme events. Our analysis is based on a review of various papers, including those presented during Extreme Space Weather Workshops held in Japan in 2011, 2012, 2013, and 2014. Large-amplitude d B/d t values are the major cause of hazards associated with three different types of GICs: (1) slow d B/d t with ring current evolution (RC-type), (2) fast d B/d t associated with auroral electrojet activity (AE-type), and (3) transient d B/d t of sudden commencements (SC-type). We set "caution," "warning," and "emergency" alert levels during the main phase of superstorms with the peak Dst index of less than -300 nT (once per 10 years), -600 nT (once per 60 years), or -900 nT (once per 100 years), respectively. The extreme d B/d t values of the AE-type GICs are 2000, 4000, and 6000 nT/min at caution, warning, and emergency levels, respectively. For the SC-type GICs, a "transient alert" is also proposed for d B/d t values of 40 nT/s at low latitudes and 110 nT/s at high latitudes, especially when the solar energetic particle flux is unusually high.

  7. Extremes in nature

    CERN Document Server

    Salvadori, Gianfausto; Kottegoda, Nathabandu T

    2007-01-01

    This book is about the theoretical and practical aspects of the statistics of Extreme Events in Nature. Most importantly, this is the first text in which Copulas are introduced and used in Geophysics. Several topics are fully original, and show how standard models and calculations can be improved by exploiting the opportunities offered by Copulas. In addition, new quantities useful for design and risk assessment are introduced.

  8. Extreme low-power mixed signal IC design

    CERN Document Server

    Tajalli, Armin

    2010-01-01

    This book describes a completely novel class of techniques for designing ultra-low-power integrated circuits (ICs). In many applications such as battery operated systems and battery-less (energy-scavenging) systems, power dissipation is a critical parameter. As a result, there is a growing demand for reducing the power (energy) consumption in ICs to extremely low levels, not achievable by using classical ""subthreshold CMOS"" techniques. This book introduces a new family of ""subthreshold circuits"" called ""source-coupled circuits"". This family of circuits can be used for implementing digita

  9. Assessment of the State of the Art of Ultra High Temperature Ceramics

    Science.gov (United States)

    Johnson, Sylvia; Gasch, Matt; Stackpoole, Mairead

    2009-01-01

    Ultra High Temperature Ceramics (UHTCs) are a family of materials that includes the borides, carbides and nitrides of hafnium-, zirconium- and titanium-based systems. UHTCs are famous for possessing some of the highest melting points of known materials. In addition, they are very hard, have good wear resistance, mechanical strength, and relatively high thermal conductivities (compared to other ceramic materials). Because of these attributes, UHTCs are ideal for thermal protection systems, especially those that require chemical and structural stability at extremely high operating temperatures. UHTCs have the potential to revolutionize the aerospace industry by enabling the development of sharp hypersonic vehicles or atmospheric entry probes capable of the most extreme entry conditions.

  10. Valley-engineered ultra-thin silicon for high-performance junctionless transistors

    Science.gov (United States)

    Kim, Seung-Yoon; Choi, Sung-Yool; Hwang, Wan Sik; Cho, Byung Jin

    2016-07-01

    Extremely thin silicon show good mechanical flexibility because of their 2-D like structure and enhanced performance by the quantum confinement effect. In this paper, we demonstrate a junctionless FET which reveals a room temperature quantum confinement effect (RTQCE) achieved by a valley-engineering of the silicon. The strain-induced band splitting and a quantum confinement effect induced from ultra-thin-body silicon are the two main mechanisms for valley engineering. These were obtained from the extremely well-controlled silicon surface roughness and high tensile strain in silicon, thereupon demonstrating a device mobility increase of ~500% in a 2.5 nm thick silicon channel device.

  11. Ultra-thin chip technology and applications

    CERN Document Server

    2010-01-01

    Ultra-thin chips are the "smart skin" of a conventional silicon chip. This book shows how very thin and flexible chips can be fabricated and used in many new applications in microelectronics, microsystems, biomedical and other fields. It provides a comprehensive reference to the fabrication technology, post processing, characterization and the applications of ultra-thin chips.

  12. Extraction of catechol violet, chrome azurol S and eriochrome cyanine R with chloroform solutions of liquid anion-exchangers.

    Science.gov (United States)

    Przeszlakowski, S; Wydra, H

    1984-06-01

    The extraction of Catechol Violet, Chrome Azurol S and Eriochrome Cyanine R with chloroform solutions of tri-n-octylamine (TOA), TOA hydrochloride and Aliquat 336 has been investigated. From the extraction isotherms, absorption spectra of the organic phases and dependence of the extraction coefficients on extractant concentration, it was found that the singly-charged anions HL(-) are extracted preferentially, but acidic groups other than sulphonate can also form ion-pairs with alkylammonium cations at higher pH values of the aqueous phase, and at high acidity these dyes can be extracted other than by an anion-exchange reaction. The three dyes (especially Eriochrome Cyanine R and Chrome Azurol S) were strongly extracted with the liquid anion-exchanger used and Aliquat 336 was a better extractant than TOA or TOA hydrochloride. The absorption spectra for the organic phases containing Chrome Azurol S and Eriochrome Cyanine R depended on the extractant used.

  13. Quantitative super-resolution localization microscopy of DNA in situ using Vybrant® DyeCycle™ Violet fluorescent probe

    Directory of Open Access Journals (Sweden)

    Dominika Żurek-Biesiada

    2016-06-01

    Full Text Available Single Molecule Localization Microscopy (SMLM is a recently emerged optical imaging method that was shown to achieve a resolution in the order of tens of nanometers in intact cells. Novel high resolution imaging methods might be crucial for understanding of how the chromatin, a complex of DNA and proteins, is arranged in the eukaryotic cell nucleus. Such an approach utilizing switching of a fluorescent, DNA-binding dye Vybrant® DyeCycle™ Violet has been previously demonstrated by us (Żurek-Biesiada et al., 2015 [1]. Here we provide quantitative information on the influence of the chemical environment on the behavior of the dye, discuss the variability in the DNA-associated signal density, and demonstrate direct proof of enhanced structural resolution. Furthermore, we compare different visualization approaches. Finally, we describe various opportunities of multicolor DNA/SMLM imaging in eukaryotic cell nuclei.

  14. Quantitative super-resolution localization microscopy of DNA in situ using Vybrant® DyeCycle™ Violet fluorescent probe.

    Science.gov (United States)

    Żurek-Biesiada, Dominika; Szczurek, Aleksander T; Prakash, Kirti; Best, Gerrit; Mohana, Giriram K; Lee, Hyun-Keun; Roignant, Jean-Yves; Dobrucki, Jurek W; Cremer, Christoph; Birk, Udo

    2016-06-01

    Single Molecule Localization Microscopy (SMLM) is a recently emerged optical imaging method that was shown to achieve a resolution in the order of tens of nanometers in intact cells. Novel high resolution imaging methods might be crucial for understanding of how the chromatin, a complex of DNA and proteins, is arranged in the eukaryotic cell nucleus. Such an approach utilizing switching of a fluorescent, DNA-binding dye Vybrant® DyeCycle™ Violet has been previously demonstrated by us (Żurek-Biesiada et al., 2015) [1]. Here we provide quantitative information on the influence of the chemical environment on the behavior of the dye, discuss the variability in the DNA-associated signal density, and demonstrate direct proof of enhanced structural resolution. Furthermore, we compare different visualization approaches. Finally, we describe various opportunities of multicolor DNA/SMLM imaging in eukaryotic cell nuclei.

  15. Photoconversion of DAPI following UV or violet excitation can cause DAPI to fluoresce with blue or cyan excitation.

    Science.gov (United States)

    Piterburg, M; Panet, H; Weiss, A

    2012-04-01

    4'-6-Diamidino-2-phenylindole is a fluorescent dye commonly used to visualize deoxyribonucleic acid or cell nuclei in fixed cell preparations, and is often used together with fluorescein or green fluorescent protein, which can be excited without exciting 4'-6-Diamidino-2-phenylindole. It is assumed that when using typical fluorescein or green fluorescent protein filter cubes, 4'-6-Diamidino-2-phenylindole will not be observed. In this paper, we show that following observation of 4'-6-Diamidino-2-phenylindole using UV or violet excitation, it may become sensitive to the blue/cyan excitation used in fluorescein/green fluorescent protein filter cubes. This has serious implications for the use of 4'-6-Diamidino-2-phenylindole together with widely used green fluorophores in double labelling experiments.

  16. Adsorption and subsequent partial photodegradation of methyl violet 2B on Cu/Al layered double hydroxides

    Science.gov (United States)

    Guzmán-Vargas, Ariel; Lima, Enrique; Uriostegui-Ortega, Gisselle A.; Oliver-Tolentino, Miguel A.; Rodríguez, Esaú E.

    2016-02-01

    Uncalcined Cu/Al LDH was studied as adsorbent and photocatalyst in the adsorption and subsequent photodegradation of methyl violet 2B dye (MV2B). Physicochemical characterization was carried out by XRD, FTIR, UV-vis, including photoactive properties, DSC/TGA and SEM. Kinetic and thermodynamic models showed great affinity and sorption capacity, the maximum adsorption capacity was 361.0 mg g-1 obtained by Langmuir model, in addition, the results showed that the dye was adsorbed on the LDH surface. Photocatalytic activity was evaluated in the MV2B dye photodegradation process, and it was confirmed by the presence rad OH radicals monitored by EPR spin trapping technique, additionally, COD and TOC parameters were measured, 13C NMR showed differences for the adsorbed and photodegraded samples.

  17. Removal of the methyl violet 2B dye from aqueous solution using sustainable adsorbent Artocarpus odoratissimus stem axis

    Science.gov (United States)

    Kooh, Muhammad Raziq Rahimi; Dahri, Muhammad Khairud; Lim, Linda B. L.

    2016-10-01

    This study investigates the potential of the stem axis of Artocarpus odoratissimus fruit (TSA) as an adsorbent for the removal of methyl violet 2B (MV). The functional group analysis was carried out using Fourier-transform infrared spectroscopy. Investigation of the effects of pH and ionic strength provide insights on the involvement of electrostatic attraction and hydrophobic-hydrophobic attraction between the adsorbent and adsorbates. Kinetics models (pseudo-first-order, pseudo-second-order, Weber-Morris and Boyd) and isotherm models (Langmuir, Freundlich and Dubinin-Raduskevich) were used for characterising the adsorption process. The Langmuir model predicted a high q m of 263.7 mg g-1. Thermodynamics studies indicate the adsorption system is spontaneous, endothermic and physical sorption dominant. The spent adsorbent was successfully regenerated using water and obtained adsorption capacity close to the unused adsorbent even after fifth cycle of washing.

  18. Small particle reagent based on crystal violet dye for developing latent fingerprints on non-porous wet surfaces

    Directory of Open Access Journals (Sweden)

    Richa Rohatgi

    2015-12-01

    Full Text Available Small particle reagent (SPR is a widely used method for developing latent fingerprints on non-porous wet surfaces. SPR based on zinc carbonate hydroxide monohydrate, ZnCo3·2Zn(OH2·H2O – also called basic zinc carbonate – has been formulated. The other ingredients of the formulation are crystal violet dye and a commercial liquid detergent. The composition develops clear, sharp and detailed fingerprints on non-porous items, after these were immersed separately in clean and dirty water for variable periods of time. The ability of the present formulation to detect weak and faint chance prints not only enhances its utility, but also its potentiality in forensic case work investigations. The raw materials used to prepare the SPR are cost-effective and non-hazardous.

  19. Adsorption of methyl violet from aqueous solution using gum xanthan/Fe3O4 based nanocomposite hydrogel.

    Science.gov (United States)

    Mittal, H; Kumar, Vaneet; Saruchi; Ray, Suprakas Sinha

    2016-08-01

    This research paper reports the utilization of gum xanthan-grafted-polyacrylic acid and Fe3O4 magnetic nanoparticles based nanocomposite hydrogel (NCH) for the highly effective adsorption of methyl violet (MV) from aqueous solution. Synthesized NCH was characterized using various techniques, such as FTIR, XRD, SEM-EDS, TEM and BET. Adsorption behavior of NCH was studied for the adsorption of MV and it was found to remove 99% dye from the solution. Adsorption process followed Langmuir isotherm model (qe=642mg/g) and pseudo-second-order kinetics model. Thermodynamic studies suggested that the adsorption process was endothermic and spontaneous. Moreover, the adsorbent was successfully utilized for successive five cycles of adsorption-desorption.

  20. Kinetic Approach to the Mechanism of Redox Reaction of Pyrocatechol Violet and Nitrite Ion in Aqueous Hydrochloric Acid

    Directory of Open Access Journals (Sweden)

    A. Adetoro

    2011-10-01

    Full Text Available The kinetics of the oxidation of Pyrocatechol violet (PCVH by nitrite ion (NO2- in aqueous acidic medium has been studied at 24±1ºC, I = 0.50 mol/dm3(NaCl, [H+] = 1.0×10-3 mol/dm3. The reaction is first order to [PCVH] and half order to [NO2-]. The redox reaction displayed a 1:1 stoichiometry and obeys the rate law: d[PCVH]/dt = (a + b[H+] [PCVH][NO2-]½. The second-order rate constant increases with increase in acid concentration and ionic strength. This system displayed positive salt effect while spectroscopic investigation and Michaelis-Menten plot showed evidence of intermediate complex formation in the course of the reaction. A plausible mechanism has been proposed for the reaction.

  1. Photo- and bio-physical characterization of novel violet and near-infrared lipophilic fluorophores for neuronal tracing.

    Science.gov (United States)

    Tonniges, J; Hansen, M; Duncan, J; Bassett, M J; Fritzsch, B; Gray, B D; Easwaran, A; Nichols, M G

    2010-08-01

    Lipophilic fluorescent dyes have been used to trace neuronal connections because of their ability to diffuse laterally within nerve cell membranes. Given the hundreds to thousands of connections that a typical neuron makes with its neighbours, a diffusion-matched set of spectrally distinct dyes is desirable. To extend a set of these dyes to obtain six independent labels, we have characterized the properties of novel violet and near-infrared candidates. By combining two-photon and confocal microscopy all of these candidates can be imaged using a single Titanium Sapphire laser. Here we present measurements of the two-photon action cross-sections and diffusion properties of the dyes, using either the relative diffusion distance or fluorescence recovery after photobleaching techniques, and demonstrate six-colour neuronal tracing within the spinal cord and brain tissue.

  2. High-power AlInGaN-based violet laser diodes with InGaN optical confinement layers

    Science.gov (United States)

    Lee, Sung-Nam; Son, J. K.; Paek, H. S.; Sung, Y. J.; Kim, K. S.; Kim, H. K.; Kim, H.; Sakong, T.; Park, Y.; Ha, K. H.; Nam, O. H.

    2008-09-01

    InGaN optical confinement layers (OCLs) were introduced into blue-violet AlInGaN-based laser diodes (LDs), resulting in the drastic improvements of lasing performance. Comparing with conventional LD structure, the lowest threshold current density of 2.3kA/cm2 has been achieved by adding 100-nm-thick InGaN OCLs which represented maximum optical confinement factor. Additionally, we observed the high quantum efficiency and the uniform emission intensity distribution of InGaN quantum wells grown on lower InGaN OCL than on typical GaN layer. Upper InGaN OCL can reduce Mg diffusion from p-type layers to InGaN active region by separating the distance between InGaN quantum wells and p-type layers.

  3. Adsorptive removal of crystal violet dye by a local clay and process optimization by response surface methodology

    Science.gov (United States)

    Loqman, Amal; El Bali, Brahim; Lützenkirchen, Johannes; Weidler, Peter G.; Kherbeche, Abdelhak

    2016-12-01

    The current study relates to the removal of a dye [crystal violet (CV)] from aqueous solutions through batch adsorption experiment onto a local clay from Morocco. The clay was characterized by X-ray diffraction, IR spectroscopy, X-ray fluorescence, scanning electron microscope, Brunauer-Emmett-Teller analysis and Fraunhofer diffraction method. The influence of independent variables on the removal efficiency was determined and optimized by response surface methodology using the Box-Behnken surface statistical design. The model predicted maximum adsorption of 81.62% under the optimum conditions of operational parameters (125 mg L-1 initial dye concentration, 2.5 g L-1 adsorbent dose and time of 43 min). Practically, the removal ranges in 27.4-95.3%.

  4. Determination of aluminium in molybdenum and tungsten metals, iron, steel and ferrous and non-ferrous alloys with pyrocatechol violet.

    Science.gov (United States)

    Donaldson, E M

    1971-09-01

    A method for determining 0.001-0.10% of aluminium in molybdenum and tungsten metals is described. After sample dissolution, aluminium is separated from the matrix materials by chloroform extraction of its acetylacetone complex, at pH 6.5, from an ammonium acetate-hydrogen peroxide medium, then back-extracted into 12M hydrochloric add. Following separation of most co-extracted elements, except for beryllium and small amounts of chroinium(III) and copper(II), by a combined ammonium pyrrolidincdithiocarbamate-cupfen-on-chlorofonn extraction, aluminium is determined spectrophotometrically with Pyrocatechol Violet at 578 nm. Chromium interferes during colour development but beryllium, in amounts equivalent to the aluminium concentration, does not cause significant error in the results. Interference from copper(II) is eliminated by reduction with ascorbic acid. The proposed method is also applicable to iron, steel, ferrovanadium, and copper-base alloys after preliminary removal of the matrix elements by a mercury cathode separation.

  5. Fluorescence, Decay Time, and Structural Change of Laser Dye Cresyl Violet in Solution due to Microwave Irradiation at GSM 900/1800 Mobile Phone Frequencies

    Directory of Open Access Journals (Sweden)

    Fuat Bayrakceken

    2012-01-01

    Full Text Available Microwave irradiation at GSM 900/1800 MHz mobile phone frequencies affects the electronic structure of cresyl violet in solution. These changes are important because laser-dye cresyl violet strongly bonds to DNA- and RNA-rich cell compounds in nerve tissues. The irradiation effects on the electronic structure of cresyl violet and its fluorescence data were all obtained experimentally at room temperature. For most laser dyes, this is not a trivial task because laser dye molecules possess a relatively complex structure. They usually consist of an extended system of conjugated double or aromatic π-bonds with attached auxochromic (electron donating groups shifting the absorption band further towards longer wavelength. Because of the intrinsically high degree of conjugation, the vibrational modes of the molecular units couple strongly with each other. We found that the fluorescence quantum yield was increased from to due to intramolecular energy hopping of cresyl violet in solution which is exposed to microwave irradiation at mobile phone frequencies, and the photonic product cannot be used as a laser dye anymore.

  6. Ultra-Deepwater Production Systems

    Energy Technology Data Exchange (ETDEWEB)

    Ken L. Smith; Marc E. Leveque

    2005-05-31

    The report herein is a summary of the work performed on three projects to demonstrate hydrocarbon drilling and production methods applicable to deep and ultra deepwater field developments in the Gulf of Mexico and other like applications around the world. This work advances technology that could lead to more economic development and exploitation of reserves in ultra-deep water or remote areas. The first project is Subsea Processing. Its scope includes a review of the ''state of the art'' in subsea components to enable primary production process functions such as first stage liquids and gas separation, flow boosting, chemical treatment, flow metering, etc. These components are then combined to allow for the elimination of costly surface production facilities at the well site. A number of studies were then performed on proposed field development projects to validate the economic potential of this technology. The second project involved the design and testing of a light weight production riser made of composite material. The proposed design was to meet an actual Gulf of Mexico deepwater development project. The various engineering and testing work is reviewed, including test results. The third project described in this report encompasses the development and testing of a close tolerance liner drilling system, a new technology aimed at reducing deepwater drilling costs. The design and prototype testing in a test well are described in detail.

  7. Aminoquinolone WR6026 as a feasible substitute for gentian violet in Chagas' disease prophylaxis in preserved blood for transfusional purposes.

    Science.gov (United States)

    Moraes-Souza, Helio; Pianetti, Gisele Marilia; Barretto, Orlando César de Oliveira Pereira; Nonoyama, Kimyo; Grolg, M; Chiari, Egler

    2002-01-01

    The search for a colorless, nontoxic and efficient drug to prevent transfusion-associated Chagas' disease (TACD) has been underway unsuccessfully since 1953 when gentian violet was preconized and to date is still being used as the only in vitro trypanocidal agent. The recent findings of aminoquinolone "WR6026" as a trypanocidal agent, led the authors to study the metabolism of red cells stored with this compound, the main objective of which was to define its applicability in TACD control. Ten units of human whole blood collected in CPDA-1 were divided into two equal satellite bags. One had "WR6026" (final concentration 62.5 g/mL) added and the other was used as a control, both were stored at 4 C. At baseline, day 7, 14, 21 and 28, samples were taken for the following measurements: adenosine triphosphate (ATP), hemoglobin, electrolytes (sodium and potassium), gases (pO2 and pCO2) and osmotic fragility. The results of tests and control were analyzed through parametric t-student test. The results were similar in both groups throughout the experiment except for the level of ATP on day 14, which presented significantly higher values in the tests when compared with the controls (p = 0.012). It was concluded that WR6026 does not interfere in the preservation and probably the viability of the erythrocytes also until day 28 of storage. Consequently the authors suggest that WR6026 could emerge as a colorless substitute for gentian violet in the control of TACD in endemic areas.

  8. Aminoquinolone WR6026 as a feasible substitute for gentian violet in Chagas' disease prophylaxis in preserved blood for transfusional purposes

    Directory of Open Access Journals (Sweden)

    Moraes-Souza Helio

    2002-01-01

    Full Text Available The search for a colorless, nontoxic and efficient drug to prevent transfusion-associated Chagas' disease (TACD has been underway unsuccessfully since 1953 when gentian violet was preconized and to date is still being used as the only in vitro trypanocidal agent. The recent findings of aminoquinolone "WR6026" as a trypanocidal agent, led the authors to study the metabolism of red cells stored with this compound, the main objective of which was to define its applicability in TACD control. Ten units of human whole blood collected in CPDA-1 were divided into two equal satellite bags. One had "WR6026" (final concentration 62.5µg/mL added and the other was used as a control, both were stored at 4ºC. At baseline, day 7, 14, 21 and 28, samples were taken for the following measurements: adenosine triphosphate (ATP, hemoglobin, electrolytes (sodium and potassium, gases (pO2 and pCO2 and osmotic fragility. The results of tests and control were analyzed through parametric t-student test. The results were similar in both groups throughout the experiment except for the level of ATP on day 14, which presented significantly higher values in the tests when compared with the controls (p = 0.012. It was concluded that WR6026 does not interfere in the preservation and probably the viability of the erythrocytes also until day 28 of storage. Consequently the authors suggest that WR6026 could emerge as a colorless substitute for gentian violet in the control of TACD in endemic areas.

  9. Structural and Optical Properties of Ultra-high Pure Hot Water Processed Ga2O3 Thin Film

    Directory of Open Access Journals (Sweden)

    Subramani SHANMUGAN

    2016-05-01

    Full Text Available Thin film based gas sensor is an advanced application of thin film especially Ga2O3 (GO thin film gas sensor is useful for high temperature gas sensor. The effect of moisture or environment on thin film properties has more influence on gas sensing properties. Radio Frequency sputtered Ga2O3 thin film was synthesized and processed in ultra-high pure hot water at 95 °C for different time durations. The structural properties were verified by the Xray Diffraction technique and the observed spectra revealed the formation of hydroxyl compound of Gallium (Gallium Oxide Dueterate – GOD on the surface of the thin film and evidenced for structural defects as an effect of moisture. Decreased crystallite size and increased dislocation density was showed the crystal defects of prepared film. From the Ultra Violet – Visible spectra, decreased optical transmittance was noticed for various processing time. The formation of needle like GOD was confirmed using Field Emission Secondary Electron Microscope (FESEM images.DOI: http://dx.doi.org/10.5755/j01.ms.22.2.7186

  10. UVUDF: Ultraviolet Through Near-infrared Catalog and Photometric Redshifts of Galaxies in the Hubble Ultra Deep Field

    CERN Document Server

    Rafelski, Marc; Gardner, Jonathan P; Coe, Dan; Bond, Nicholas A; Koekemoer, Anton M; Grogin, Norman; Kurczynski, Peter; McGrath, Elizabeth J; Bourque, Matthew; Atek, Hakim; Brown, Thomas M; Colbert, James W; Codoreanu, Alex; Ferguson, Henry C; Finkelstein, Steven L; Gawiser, Eric; Giavalisco, Mauro; Gronwall, Caryl; Hanish, Daniel J; Lee, Kyoung-Soo; Mehta, Vihang; de Mello, Duilia F; Ravindranath, Swara; Ryan, Russell E; Scarlata, Claudia; Siana, Brian; Soto, Emmaris; Voyer, Elysse N

    2015-01-01

    We present photometry and derived redshifts from up to eleven bandpasses for 9927 galaxies in the Hubble Ultra Deep field (UDF), covering an observed wavelength range from the near-ultraviolet (NUV) to the near-infrared (NIR) with Hubble Space Telescope observations. Our Wide Field Camera 3 (WFC3)/UV F225W, F275W, and F336W image mosaics from the ultra-violet UDF (UVUDF) imaging campaign are newly calibrated to correct for charge transfer inefficiency, and use new dark calibrations to minimize background gradients and pattern noise. Our NIR WFC3/IR image mosaics combine the imaging from the UDF09 and UDF12 campaigns with CANDELS data to provide NIR coverage for the entire UDF field of view. We use aperture-matched point-spread function corrected photometry to measure photometric redshifts in the UDF, sampling both the Lyman break and Balmer break of galaxies at z~0.8-3.4, and one of the breaks over the rest of the redshift range. Our comparison of these results with a compilation of robust spectroscopic redsh...

  11. Consumers' conceptualization of ultra-processed foods.

    Science.gov (United States)

    Ares, Gastón; Vidal, Leticia; Allegue, Gimena; Giménez, Ana; Bandeira, Elisa; Moratorio, Ximena; Molina, Verónika; Curutchet, María Rosa

    2016-10-01

    Consumption of ultra-processed foods has been associated with low diet quality, obesity and other non-communicable diseases. This situation makes it necessary to develop educational campaigns to discourage consumers from substituting meals based on unprocessed or minimally processed foods by ultra-processed foods. In this context, the aim of the present work was to investigate how consumers conceptualize the term ultra-processed foods and to evaluate if the foods they perceive as ultra-processed are in concordance with the products included in the NOVA classification system. An online study was carried out with 2381 participants. They were asked to explain what they understood by ultra-processed foods and to list foods that can be considered ultra-processed. Responses were analysed using inductive coding. The great majority of the participants was able to provide an explanation of what ultra-processed foods are, which was similar to the definition described in the literature. Most of the participants described ultra-processed foods as highly processed products that usually contain additives and other artificial ingredients, stressing that they have low nutritional quality and are unhealthful. The most relevant products for consumers' conceptualization of the term were in agreement with the NOVA classification system and included processed meats, soft drinks, snacks, burgers, powdered and packaged soups and noodles. However, some of the participants perceived processed foods, culinary ingredients and even some minimally processed foods as ultra-processed. This suggests that in order to accurately convey their message, educational campaigns aimed at discouraging consumers from consuming ultra-processed foods should include a clear definition of the term and describe some of their specific characteristics, such as the type of ingredients included in their formulation and their nutritional composition.

  12. Extreme Programming Pocket Guide

    CERN Document Server

    Chromatic

    2003-01-01

    Extreme Programming (XP) is a radical new approach to software development that has been accepted quickly because its core practices--the need for constant testing, programming in pairs, inviting customer input, and the communal ownership of code--resonate with developers everywhere. Although many developers feel that XP is rooted in commonsense, its vastly different approach can bring challenges, frustrations, and constant demands on your patience. Unless you've got unlimited time (and who does these days?), you can't always stop to thumb through hundreds of pages to find the piece of info

  13. Mycetoma of lower extremity

    Directory of Open Access Journals (Sweden)

    Sahariah S

    1978-01-01

    Full Text Available Ten cases of mycetoma of the lower extremity were seen and treated at the Postgraduate Institute of Medical Education & Research, Chandigarh, India, during the years 1973 to 1975. Six were treated by conservative method e.g. antibiotics, sulfonamides and immobilization of the part while remaining four were submitted t o surgery. Four out o f six from the first group had recurrence and has been put on second line of therapy. Recurrence occurred in only one case from the second group and he required an above knee amputation while the remaining three are free of disease and are well rehabilitated.

  14. Metagenomics of extreme environments.

    Science.gov (United States)

    Cowan, D A; Ramond, J-B; Makhalanyane, T P; De Maayer, P

    2015-06-01

    Whether they are exposed to extremes of heat or cold, or buried deep beneath the Earth's surface, microorganisms have an uncanny ability to survive under these conditions. This ability to survive has fascinated scientists for nearly a century, but the recent development of metagenomics and 'omics' tools has allowed us to make huge leaps in understanding the remarkable complexity and versatility of extremophile communities. Here, in the context of the recently developed metagenomic tools, we discuss recent research on the community composition, adaptive strategies and biological functions of extremophiles.

  15. Characterizing Extreme Ionospheric Storms

    Science.gov (United States)

    Sparks, L.; Komjathy, A.; Altshuler, E.

    2011-12-01

    Ionospheric storms consist of disturbances of the upper atmosphere that generate regions of enhanced electron density typically lasting several hours. Depending upon the storm magnitude, gradients in electron density can sometimes become large and highly localized. The existence of such localized, dense irregularities is a major source of positioning error for users of the Global Positioning System (GPS). Consequently, satellite-based augmentation systems have been implemented to improve the accuracy and to ensure the integrity of user position estimates derived from GPS measurements. Large-scale irregularities generally do not pose a serious threat to estimate integrity as they can be readily detected by such systems. Of greater concern, however, are highly localized irregularities that interfere with the propagation of a signal detected by a user measurement but are poorly sampled by the receivers in the system network. The most challenging conditions have been found to arise following disturbances of large magnitude that occur only rarely over the course of a solar cycle. These extremely disturbed conditions exhibit behavior distinct from moderately disturbed conditions and, hence, have been designated "extreme storms". In this paper we examine and compare the behavior of the extreme ionospheric storms of solar cycle 23 (or, more precisely, extreme storms occurring between January 1, 2000, and December 31, 2008), as represented in maps of vertical total electron content. To identify these storms, we present a robust means of quantifying the regional magnitude of an ionospheric storm. Ionospheric storms are observed frequently to occur in conjunction with magnetic storms, i.e., periods of geophysical activity as measured by magnetometers. While various geomagnetic indices, such as the disturbance storm time (Dst) and the planetary Kp index, have long been used to rank the magnitudes of distinct magnetic storms, no comparable, generally recognized index exists for

  16. Extending ultra-short pulse laser texturing over large area

    Energy Technology Data Exchange (ETDEWEB)

    Mincuzzi, G., E-mail: girolamo.mincuzzi@alphanov.com; Gemini, L.; Faucon, M.; Kling, R.

    2016-11-15

    Highlights: • We carried out metal surface texturing (Ripples, micro grooves, Spikes) using a high power, high repetition rate, industrial, Ultra-short pulses laser. • Extremely Fast processing is shown (Laser Scan speed as high as 90 m/s) with a polygon scanner head. • Stainless steel surface blackening with Ultra-short pulses laser has been obtained with unprecedented scanspeed. • Full SEM surface characterization was carried out for all the different structures obtained. • Reflectance measurements were carried out to characterize surface reflectance. - Abstract: Surface texturing by Ultra-Short Pulses Laser (UPL) for industrial applications passes through the use of both fast beam scanning systems and high repetition rate, high average power P, UPL. Nevertheless unwanted thermal effects are expected when P exceeds some tens of W. An interesting strategy for a reliable heat management would consists in texturing with a low fluence values (slightly higher than the ablation threshold) and utilising a Polygon Scanner Heads delivering laser pulses with unrepeated speed. Here we show for the first time that with relatively low fluence it is possible over stainless steel, to obtain surface texturing by utilising a 2 MHz femtosecond laser jointly with a polygonal scanner head in a relatively low fluence regime (0.11 J cm{sup −2}). Different surface textures (Ripples, micro grooves and spikes) can be obtained varying the scan speed from 90 m s{sup −1} to 25 m s{sup −1}. In particular, spikes formation process has been shown and optimised at 25 m s{sup −1} and a full morphology characterization by SEM has been carried out. Reflectance measurements with integrating sphere are presented to compare reference surface with high scan rate textures. In the best case we show a black surface with reflectance value < 5%.

  17. Winter Storms and Extreme Cold

    Science.gov (United States)

    ... Landslides & Debris Flow Nuclear Blast Nuclear Power Plants Power Outages Pandemic Radiological Dispersion Device Severe Weather Snowstorms & Extreme ... Landslides & Debris Flow Nuclear Blast Nuclear Power Plants Power Outages Pandemic Radiological Dispersion Device Severe Weather Snowstorms & Extreme ...

  18. EFFECTS OF ULTRA REIZ CURRENT AND TENS ON PAIN AND FUNCTIONAL ABILITY IN OLDER PATIENTS WITH OSTEO ARTHRITIS KNEE

    Directory of Open Access Journals (Sweden)

    Siddhartha Sen

    2013-10-01

    Full Text Available Background and introduction:Osteoarthritis is a degenerative joint disease where Progressive destructionarticular cartilage and formation of bone at the margin of the joint happens. This is extremely common conditionIt is evident that ultra reiz current is good analgesic and can improve circulation locally, but there is least workof ultra reiz on osteoarthritis. Ultra reiz current is more effective in comparison with tens in reducing pain andincreasing functional ability of older adults with osteoarthritis knee.Purpose of the study:is To determine theeffect of ultra reiz current on pain and functional ability of osteoarthritis knee and to determinethe effects ofultra reiz current in comparison with TENS.Methodology:On the basis of inclusion and exclusion criteriasubjects was screened and included in the study. Convenient sampling was done with random assignmenttothree treatment groups where Group-A (experimental undertook ultra reiz current and exercise, Group-B(experimental TENS and exercise, Group- C (control only exercise. The outcome measure was pain & Functionalability and measured with WOMAC scale. The data was collected in pre intervention at the 1stweek and postintervention at the 2ndweek.Result:data was analyzed by using ANOVA and the result showed there is decreasein VAS score and improve in functional ability.Conclusion:The study concluded that Ultra reiz current andTENS show similar improvement in relieving pain and functional ability in comparison with TENS in older patientswith osteoarthritis knee.

  19. Ultra High Energy Neutrino Signature in Top-Down Scenario

    CERN Document Server

    Aloisio, R

    2006-01-01

    Neutrinos are the best candidates to test the extreme Universe and ideas beyond the Standard Model of particle Physics. Once produced, neutrinos do not suffer any kind of attenuation by intervening radiation fields like the Cosmic Microwave Background and are not affected by magnetic fields. In this sense neutrinos are useful messengers from the far and young Universe. In the present paper we will discuss a particular class of sources of Ultra High Energy Cosmic Rays introduced to explain the possible excess of events with energy larger than the Graisen-Zatsepin-Kuzmin cut-off. These sources, collectively called top-down, share a common feature: UHE particles are produced in the decay or annihilation of superheavy, exotic, particles. As we will review in the present paper, the largest fraction of Ultra High Energy particles produced in the top-down scenario are neutrinos. The study of these radiation offers us a unique opportunity to test the exotic mechanisms of the top-down scenario.

  20. Ultra-compact Marx-type high-voltage generator

    Science.gov (United States)

    Goerz, David A.; Wilson, Michael J.

    2000-01-01

    An ultra-compact Marx-type high-voltage generator includes individual high-performance components that are closely coupled and integrated into an extremely compact assembly. In one embodiment, a repetitively-switched, ultra-compact Marx generator includes low-profile, annular-shaped, high-voltage, ceramic capacitors with contoured edges and coplanar extended electrodes used for primary energy storage; low-profile, low-inductance, high-voltage, pressurized gas switches with compact gas envelopes suitably designed to be integrated with the annular capacitors; feed-forward, high-voltage, ceramic capacitors attached across successive switch-capacitor-switch stages to couple the necessary energy forward to sufficiently overvoltage the spark gap of the next in-line switch; optimally shaped electrodes and insulator surfaces to reduce electric field stresses in the weakest regions where dissimilar materials meet, and to spread the fields more evenly throughout the dielectric materials, allowing them to operate closer to their intrinsic breakdown levels; and uses manufacturing and assembly methods to integrate the capacitors and switches into stages that can be arranged into a low-profile Marx generator.

  1. Active Galactic Nuclei: Sources for ultra high energy cosmic rays?

    Energy Technology Data Exchange (ETDEWEB)

    Biermann, Peter L. [MPI for Radioastronomy, Bonn (Germany); Dept. of Phys. and Astron., Univ. of Bonn (Germany); Dept. of Phys. and Astr., Univ. of Alabama, Tuscaloosa, AL (United States); Dept. of Phys., Univ. of Alabama at Huntsville, AL (United States); Inst. Nucl. Phys. FZ, Karlsruhe Inst. of Techn. (KIT) (Germany); Becker, Julia K. [Institution foer Fysik, Goeteborgs Univ. (Sweden); Dept. of Phys., Univ. Dortmund, Dortmund (Germany); Caramete, Laurentiu [MPI for Radioastronomy, Bonn (Germany); Institute for Space Studies, Bucharest (Romania); Curutiu, Alex [MPI for Radioastronomy, Bonn (Germany); Engel, Ralph [Inst. Nucl. Phys. FZ, Karlsruhe Inst. of Techn. (KIT) (Germany); Falcke, Heino [Dept. of Astrophys., IMAP, Radboud Univ., Nijmegen (Netherlands); ASTRON, Dwingeloo (Netherlands); Gergely, Laszlo A. [Dept. Appl. Sci., London South Bank University (United Kingdom); Dept. of Theoret. and Exp. Phys., Univ. of Szeged, Szeged (Hungary); Isar, P. Gina [Inst. Nucl. Phys. FZ, Karlsruhe Inst. of Techn. (KIT) (Germany); Institute for Space Studies, Bucharest (Romania); Maris, Ioana C. [Inst. Nucl. Phys. FZ, Karlsruhe Inst. of Techn. (KIT) (Germany); Meli, Athina [Physik. Inst. Univ. Erlangen-Nuernberg (Germany); Kampert, Karl-Heinz [Phys. Dept., Univ. Wuppertal (Germany); Stanev, Todor [Bartol Research Inst., Univ. of Delaware, Newark, DE (United States); Tascau, Oana [Phys. Dept., Univ. Wuppertal (Germany); Zier, Christian [MPI for Radioastronomy, Bonn (Germany); Raman Res. Inst., Bangalore (India)

    2009-05-15

    The origin of ultra high energy cosmic rays promises to lead us to a deeper understanding of the structure of matter. This is possible through the study of particle collisions at center-of-mass energies in interactions far larger than anything possible with the Large Hadron Collider, albeit at the substantial cost of no control over the sources and interaction sites. For the extreme energies we have to identify and understand the sources first, before trying to use them as physics laboratories. Here we describe the current stage of this exploration. The most promising contenders as sources are radio galaxies and gamma ray bursts. The sky distribution of observed events yields a hint favoring radio galaxies. Key in this quest are the intergalactic and galactic magnetic fields, whose strength and structure are not yet fully understood. Current data and statistics do not yet allow a final judgement. We outline how we may progress in the near future.

  2. Observational signatures of modified gravity on ultra-large scales

    CERN Document Server

    Baker, Tessa

    2015-01-01

    Extremely large surveys with future experiments like Euclid and the SKA will soon allow us to access perturbation modes close to the Hubble scale, with wavenumbers $k \\sim {\\cal H}$. If a modified gravity theory is responsible for cosmic acceleration, the Hubble scale is a natural regime for deviations from General Relativity (GR) to become manifest. The majority of studies to date have concentrated on the consequences of alternative gravity theories for the subhorizon, quasi-static regime, however. We investigate how modifications to the gravitational field equations affect perturbations around the Hubble scale, and how this translates into deviations of ultra large-scale relativistic observables from their GR behaviour. Adopting a model-independent ethos that relies only on the broad physical properties of gravity theories, we find that the deviations of the observables are small unless modifications to GR are drastic. The angular dependence and redshift evolution of the deviations is highly parameterisatio...

  3. Implications of the causality principle for ultra chiral metamaterials

    Science.gov (United States)

    Gorkunov, Maxim V.; Dmitrienko, Vladimir E.; Ezhov, Alexander A.; Artemov, Vladimir V.; Rogov, Oleg Y.

    2015-01-01

    Chiral metamaterials – artificial subwavelength structures with broken mirror symmetry – demonstrate outstanding degree of optical chirality that exhibits sophisticated spectral behavior and can eventually reach extreme values. Based on the fundamental causality principle we show how one can unambiguously relate the metamaterial circular dichroism and optical activity by the generalized Kramers-Kronig relations. Contrary to the conventional relations, the generalized ones provide a unique opportunity of extracting information on material-dependent zeroes of transmission coefficient in the upper half plane of complex frequency. We illustrate the merit of the formulated relations by applying them to the observed ultra chiral optical transmission spectra of subwavelength arrays of chiral holes in silver films. Apart from the possibility of precise verification of experimental data, the relations enable resolving complex eigenfrequencies of metamaterial intrinsic modes and resonances. PMID:25787007

  4. Ultra-portable, wireless smartphone spectrometer for rapid, non-destructive testing of fruit ripeness.

    Science.gov (United States)

    Das, Anshuman J; Wahi, Akshat; Kothari, Ishan; Raskar, Ramesh

    2016-09-08

    We demonstrate a smartphone based spectrometer design that is standalone and supported on a wireless platform. The device is inherently low-cost and the power consumption is minimal making it portable to carry out a range of studies in the field. All essential components of the device like the light source, spectrometer, filters, microcontroller and wireless circuits have been assembled in a housing of dimensions 88 mm × 37 mm × 22 mm and the entire device weighs 48 g. The resolution of the spectrometer is 15 nm, delivering accurate and repeatable measurements. The device has a dedicated app interface on the smartphone to communicate, receive, plot and analyze spectral data. The performance of the smartphone spectrometer is comparable to existing bench-top spectrometers in terms of stability and wavelength resolution. Validations of the device were carried out by demonstrating non-destructive ripeness testing in fruit samples. Ultra-Violet (UV) fluorescence from Chlorophyll present in the skin was measured across various apple varieties during the ripening process and correlated with destructive firmness tests. A satisfactory agreement was observed between ripeness and fluorescence signals. This demonstration is a step towards possible consumer, bio-sensing and diagnostic applications that can be carried out in a rapid manner.

  5. Ultra-portable, wireless smartphone spectrometer for rapid, non-destructive testing of fruit ripeness

    Science.gov (United States)

    Das, Anshuman J.; Wahi, Akshat; Kothari, Ishan; Raskar, Ramesh

    2016-09-01

    We demonstrate a smartphone based spectrometer design that is standalone and supported on a wireless platform. The device is inherently low-cost and the power consumption is minimal making it portable to carry out a range of studies in the field. All essential components of the device like the light source, spectrometer, filters, microcontroller and wireless circuits have been assembled in a housing of dimensions 88 mm × 37 mm × 22 mm and the entire device weighs 48 g. The resolution of the spectrometer is 15 nm, delivering accurate and repeatable measurements. The device has a dedicated app interface on the smartphone to communicate, receive, plot and analyze spectral data. The performance of the smartphone spectrometer is comparable to existing bench-top spectrometers in terms of stability and wavelength resolution. Validations of the device were carried out by demonstrating non-destructive ripeness testing in fruit samples. Ultra-Violet (UV) fluorescence from Chlorophyll present in the skin was measured across various apple varieties during the ripening process and correlated with destructive firmness tests. A satisfactory agreement was observed between ripeness and fluorescence signals. This demonstration is a step towards possible consumer, bio-sensing and diagnostic applications that can be carried out in a rapid manner.

  6. Predictions for Ultra-Deep Radio Counts of Star-Forming Galaxies

    CERN Document Server

    Mancuso, Claudia; Cai, Zhen-Yi; Negrello, Mattia; De Zotti, Gianfranco; Bressan, Alessandro; Bonato, Matteo; Perrotta, Francesca; Danese, Luigi

    2015-01-01

    We have worked out predictions for the radio counts of star-forming galaxies down to nJy levels, along with redshift distributions down to the detection limits of the phase 1 Square Kilometer Array MID telescope (SKA1-MID) and of its precursors. Such predictions were obtained by coupling epoch dependent star formation rate (SFR) functions with relations between SFR and radio (synchrotron and free-free) emission. The SFR functions were derived taking into account both the dust obscured and the unobscured star-formation, by combining far-infrared (FIR), ultra-violet (UV) and H_alpha luminosity functions up to high redshifts. We have also revisited the South Pole Telescope (SPT) counts of dusty galaxies at 95\\,GHz performing a detailed analysis of the Spectral Energy Distributions (SEDs). Our results show that the deepest SKA1-MID surveys will detect high-z galaxies with SFRs two orders of magnitude lower compared to Herschel surveys. The highest redshift tails of the distributions at the detection limits of pla...

  7. Ultra-cold molecule production.

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-Serrano, Jamie; Chandler, David W.; Strecker, Kevin; Rahn, Larry A.

    2005-12-01

    The production of Ultra-cold molecules is a goal of many laboratories through out the world. Here we are pursuing a unique technique that utilizes the kinematics of atomic and molecular collisions to achieve the goal of producing substantial numbers of sub Kelvin molecules confined in a trap. Here a trap is defined as an apparatus that spatially localizes, in a known location in the laboratory, a sample of molecules whose temperature is below one degree absolute Kelvin. Further, the storage time for the molecules must be sufficient to measure and possibly further cool the molecules. We utilize a technique unique to Sandia to form cold molecules from near mass degenerate collisions between atoms and molecules. This report describes the progress we have made using this novel technique and the further progress towards trapping molecules we have cooled.

  8. Hemispheric ultra-wideband antenna.

    Energy Technology Data Exchange (ETDEWEB)

    Brocato, Robert Wesley

    2006-04-01

    This report begins with a review of reduced size ultra-wideband (UWB) antennas and the peculiar problems that arise when building a UWB antenna. It then gives a description of a new type of UWB antenna that resolves these problems. This antenna, dubbed the hemispheric conical antenna, is similar to a conventional conical antenna in that it uses the same inverted conical conductor over a ground plane, but it also uses a hemispheric dielectric fill in between the conductive cone and the ground plane. The dielectric material creates a fundamentally new antenna which is reduced in size and much more rugged than a standard UWB conical antenna. The creation of finite-difference time domain (FDTD) software tools in spherical coordinates, as described in SAND2004-6577, enabled this technological advance.

  9. Analysis of ultra-triathlon performances

    Directory of Open Access Journals (Sweden)

    Rosemann T

    2011-08-01

    Full Text Available Romuald Lepers1, Beat Knechtle2,3, Patrizia Knechtle2, Thomas Rosemann2 1INSERM U887, Faculty of Sport Sciences, University of Burgundy, Dijon, France; 2Institute of General Practice and Health Services Research, University of Zurich, Switzerland; 3Gesundheitszentrum St Gallen, St Gallen, Switzerland Abstract: Despite increased interest in ultra-endurance events, little research has examined ultra-triathlon performance. The aims of this study were: (i to compare swimming, cycling, running, and overall performances in three ultra-distance triathlons, double Ironman distance triathlon (2IMT (7.6 km swimming, 360 km cycling, and 84.4 km running, triple Ironman distance triathlon (3IMT (11.4 km, 540 km, and 126.6 km, and deca Ironman distance triathlon (10IMT (38 km, 1800 km, and 420 km and (ii to examine the relationships between the 2IMT, 3IMT, and 10IMT performances to create predicted equations of the 10IMT performances. Race results from 1985 through 2009 were examined to identify triathletes who performed the three considered ultra-distances. In total, 73 triathletes (68 men and 5 women were identified. The contribution of swimming to overall ultra-triathlon performance was lower than for cycling and running. Running performance was more important to overall performance for 2IMT and 3IMT compared with 10IMT. The 2IMT and 3IMT performances were significantly correlated with 10IMT performances for swimming and cycling, but not for running. 10IMT total time performance might be predicted by the following equation: 10IMT race time (minutes = 5885 + 3.69 × 3IMT race time (minutes. This analysis of human performance during ultra-distance triathlons represents a unique data set in the field of ultra-endurance events. Additional studies are required to determine the physiological and psychological factors associated with ultra-triathlon performance. Keywords: triathlon, swimming, cycling, running, ultra-endurance 

  10. 21 CFR 177.2910 - Ultra-filtration membranes.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Ultra-filtration membranes. 177.2910 Section 177... Components of Articles Intended for Repeated Use § 177.2910 Ultra-filtration membranes. Ultra-filtration... the processing of food, under the following prescribed conditions; (a)(1) Ultra-filtration...

  11. Development of Compressor for Ultra Micro Gas Turbine

    Institute of Scientific and Technical Information of China (English)

    Shimpei MIZUKI

    2007-01-01

    The major problems for the development of an ultra micro gas turbine system were discussed briefly from the stand point of the internal flow and the performance characteristics. Following to these, the development of ultra micro centrifugal compression systems for the ultra micro gas turbine is explained with the design and the manufacturing processes. The measured results of ultra micro centrifugal compressors are shown.

  12. Ultras in Trnava: History, Activities and Ideology

    Directory of Open Access Journals (Sweden)

    Kušnierová Daniela

    2014-12-01

    Full Text Available The environment of football fans is unknown phenomenon for the rest of the public. This article offers basic view on formation and functioning of the most numerous and the most active ultras group in Slovakia, Trnava fans. First part of the text encompasses a history overview of ultras movement, as well as an overview of basic activities of ultras fans during a football match and also outside of it. The second part of this text deals with the most debated activity of football fans, which is violence during a football match.

  13. Extreme light infrastructure: laser architecture and major challenges

    Science.gov (United States)

    Chambaret, J.-P.; Chekhlov, O.; Cheriaux, G.; Collier, J.; Dabu, R.; Dombi, P.; Dunne, A. M.; Ertel, K.; Georges, P.; Hebling, J.; Hein, J.; Hernandez-Gomez, C.; Hooker, C.; Karsch, S.; Korn, G.; Krausz, F.; Le Blanc, C.; Major, Zs.; Mathieu, F.; Metzger, T.; Mourou, G.; Nickles, P.; Osvay, K.; Rus, B.; Sandner, W.; Szabó, G.; Ursescu, D.; Varjú, K.

    2010-05-01

    Extreme Light Infrastructure (ELI), the first research facility hosting an exawatt class laser will be built with a joint international effort and form an integrated infrastructure comprised at last three branches: Attosecond Science (in Szeged, Hungary) designed to make temporal investigation at the attosecond scale of electron dynamics in atoms, molecules, plasmas and solids. High Field Science will be mainly focused on producing ultra intense and ultra short sources of electons, protons and ions, coherent and high energetic X rays (in Prague, Czech Republic) as well as laserbased nuclear physics (in Magurele, Romania). The location of the fourth pillar devoted to Extreme Field Science, which will explore laser-matter interaction up to the non linear QED limit including the investigation of vacuum structure and pair creation, will be decided after 2012. The research activities will be based on an incremental development of the light sources starting from the current high intensity lasers (APOLLON, GEMINI, Vulcan and PFS) as prototypes to achieve unprecedented peak power performance, from tens of petawatt up to a fraction of exawatt (1018 W). This last step will depend on the laser technology development in the above three sites as well as in current high intensity laser facilities.

  14. Precipitation extremes under climate change

    CERN Document Server

    O'Gorman, Paul A

    2015-01-01

    The response of precipitation extremes to climate change is considered using results from theory, modeling, and observations, with a focus on the physical factors that control the response. Observations and simulations with climate models show that precipitation extremes intensify in response to a warming climate. However, the sensitivity of precipitation extremes to warming remains uncertain when convection is important, and it may be higher in the tropics than the extratropics. Several physical contributions govern the response of precipitation extremes. The thermodynamic contribution is robust and well understood, but theoretical understanding of the microphysical and dynamical contributions is still being developed. Orographic precipitation extremes and snowfall extremes respond differently from other precipitation extremes and require particular attention. Outstanding research challenges include the influence of mesoscale convective organization, the dependence on the duration considered, and the need to...

  15. "Triangular" extremal dilatonic dyons

    CERN Document Server

    Gal'tsov, Dmitri; Orlov, Dmitri

    2014-01-01

    Explicit dyonic dilaton black holes of the four-dimensional Einstein-Maxwell-dilaton theory are known only for two particular values of the dilaton coupling constant $a =1,\\sqrt{3}$, while for other $a$ numerical evidence was presented earlier about existence of extremal dyons in theories with the discrete sequence of dilaton couplings $a=\\sqrt{n(n+1)/2}$ with integer $n$. Apart from the lower members $n=1,\\,2$, this family of theories does not have motivation from supersymmetry or higher dimensions, and so far the above quantization rule has not been derived analytically. We fill this gap showing that this rule follows from analyticity of the dilaton at the $AdS_2\\times S^2$ event horizon with $n$ being the leading dilaton power in the series expansion. We also present generalization for asymptotically anti-de Sitter dyonic black holes with spherical, plane and hyperbolic topology of the horizon.

  16. Extreme skin depth waveguides

    CERN Document Server

    Jahani, Saman

    2014-01-01

    Recently, we introduced a paradigm shift in light confinement strategy and introduced a class of extreme skin depth (e-skid) photonic structures (S. Jahani and Z. Jacob, "Transparent sub-diffraction optics: nanoscale light confinement without metal," Optica 1, 96-100 (2014)). Here, we analytically establish that figures of merit related to light confinement in dielectric waveguides are fundamentally tied to the skin depth of waves in the cladding. We contrast the propagation characteristics of the fundamental mode of e-skid waveguides and conventional waveguides to show that the decay constant in the cladding is dramatically larger in e-skid waveguides, which is the origin of sub-diffraction confinement. Finally, we propose an approach to verify the reduced skin depth in experiment using the decrease in the Goos-H\\"anchen phase shift.

  17. Pulsars and Extreme Physics

    Science.gov (United States)

    Bell-Burnell, Jocelyn

    2004-10-01

    Pulsars were discovered 35 years ago. What do we know about them now, and what have they taught us about the extremes of physics? With an average density comparable to that of the nucleus, magnetic fields around 108 T and speeds close to c these objects have stretched our understanding of the behaviour of matter. They serve as extrememly accurate clocks with which to carry out precision experiments in relativity. Created in cataclysmic explosions, pulsars are a (stellar) form of life after death. After half a billion revolutions most pulsars finally die, but amazingly some are born again to yet another, even weirder, afterlife. Pulsar research continues lively, delivering exciting, startling and almost unbelievable results!

  18. Do ultra-orphan medicinal products warrant ultra-high prices? A review

    Directory of Open Access Journals (Sweden)

    Picavet E

    2013-06-01

    Full Text Available Eline Picavet,1 David Cassiman,2 Steven Simoens1 1Department of Pharmaceutical and Pharmacological Sciences, KU Leuven, Leuven, Belgium; 2Department of Hepatology, University Hospital Leuven, Leuven, Belgium Abstract: Ultra-orphan medicinal products (ultra-OMPs are intended for the treatment, prevention, or diagnosis of ultra-rare diseases, ie, life-threatening or chronically debilitating diseases that affect less than one per 50,000 individuals. Recently, high prices for ultra-OMPs have given rise to debate on the sustainability and justification of these prices. The aim of this article is to review the international scientific literature on the pricing of ultra-OMPs and to provide an overview of the current knowledge on the drivers of ultra-OMP pricing. The pricing process of ultra-OMPs is a complex and nontransparent issue. Evidence in the literature seems to indicate that ultra-OMPs are priced according to rarity and what the manufacturer believes the market will bear. Additionally, there appears to be a trend between the price of an ultra-OMP and the number of available alternatives. Patients, third-party payers, and pharmaceutical companies could benefit from more transparent pricing strategies. With a view to containing health care costs, it is likely that cost-sharing strategies, such as performance-based risk sharing arrangements, will become increasingly more important. However, it is vital that any measures for price control are consistent with the intended goals of the incentives to promote the development of new OMPs. Ideally, a balance must be struck between attaining affordable prices for ultra-OMPs and securing a realistic return on investment for the pharmaceutical industry. Keywords: ultra-orphan medicinal product, ultra-rare disease, pricing

  19. Extreme Adaptive Optics Planet Imager: XAOPI

    Energy Technology Data Exchange (ETDEWEB)

    Macintosh, B A; Graham, J; Poyneer, L; Sommargren, G; Wilhelmsen, J; Gavel, D; Jones, S; Kalas, P; Lloyd, J; Makidon, R; Olivier, S; Palmer, D; Patience, J; Perrin, M; Severson, S; Sheinis, A; Sivaramakrishnan, A; Troy, M; Wallace, K

    2003-09-17

    Ground based adaptive optics is a potentially powerful technique for direct imaging detection of extrasolar planets. Turbulence in the Earth's atmosphere imposes some fundamental limits, but the large size of ground-based telescopes compared to spacecraft can work to mitigate this. We are carrying out a design study for a dedicated ultra-high-contrast system, the eXtreme Adaptive Optics Planet Imager (XAOPI), which could be deployed on an 8-10m telescope in 2007. With a 4096-actuator MEMS deformable mirror it should achieve Strehl >0.9 in the near-IR. Using an innovative spatially filtered wavefront sensor, the system will be optimized to control scattered light over a large radius and suppress artifacts caused by static errors. We predict that it will achieve contrast levels of 10{sup 7}-10{sup 8} at angular separations of 0.2-0.8 inches around a large sample of stars (R<7-10), sufficient to detect Jupiter-like planets through their near-IR emission over a wide range of ages and masses. We are constructing a high-contrast AO testbed to verify key concepts of our system, and present preliminary results here, showing an RMS wavefront error of <1.3 nm with a flat mirror.

  20. Ultra fine tantalum powder for advanced capacitors

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    @@ Ultra fine tantalum and niobium powders are applicable in many areas of engineering. Of particular significance are high purity powders that are usable in production of high capacitance capacitors and superconductors.

  1. Ultra fine tantalum powder for advanced capacitors

    Institute of Scientific and Technical Information of China (English)

    Nebera; A.; Markusbkin; Yu.; Azarov; V.; Ermolaev; N.

    2005-01-01

    Ultra fine tantalum and niobium powders are applicable in many areas of engineering. Of particular significance are high purity powders that are usable in production of high capacitance capacitors and superconductors.……

  2. Special techniques in ultra-precision machining

    Science.gov (United States)

    Li, Li; Min, Xu; Chen, Dong; Wang, JunHua

    2007-12-01

    As the development of ultra-precision machining, the SPDT (single point diamond turning) was applied for the manufacture of a variety of optical components for its high precision , versatility and lower manufacturing cost. Whereas, the improvement of ultra-precision machining is not only related to the most topnotch equipments in the world but also closely linked to the special techniques in the ultra-precision Machining. Therefore, the industrialization and marketization of the ultra-precision machining will not be realized without these special techniques. This paper introduces the principle, trait and application of some important special techniques which can match the SPDT efficaciously, they are FTS, STS, SSS, ACT, VQ, LADT and UADT techniques.

  3. ULTRA BARRIER TOPSHEET (UBT) FOR FLEXIBLE PHOTOVOLTAICS

    Energy Technology Data Exchange (ETDEWEB)

    DeScioli, Derek

    2013-06-01

    This slide-show presents 3M photovoltaic-related products, particularly flexible components. Emphasis is on the 3M Ultra Barrier Solar Films. Topics covered include reliability and qualification testing and flexible photovoltaic encapsulation costs.

  4. Introduction to Ultra Wideband for Wireless Communications

    DEFF Research Database (Denmark)

    Nikookar, Homayoun; Prasad, Ramjee

    wireless channels, interference, signal processing as well as applications and standardization activities are addressed. Introduction to Ultra Wideband for Wireless Communications provides easy-to-understand material to (graduate) students and researchers working in the field of commercial UWB wireless......Ultra Wideband (UWB) Technology is the cutting edge technology for wireless communications with a wide range of applications. In Introduction to Ultra Wideband for Wireless Communications UWB principles and technologies for wireless communications are explained clearly. Key issues such as UWB...... communications. Due to tutorial nature of the book it can also be adopted as a textbook on the subject in the Telecommunications Engineering curriculum. Problems at the end of each chapter extend the reader's understanding of the subject. Introduction to Ultra Wideband for Wireless Communications will aslo...

  5. Successful Treatment of Severe Tungiasis in Pigs Using a Topical Aerosol Containing Chlorfenvinphos, Dichlorphos and Gentian Violet

    Science.gov (United States)

    Mutebi, Francis; von Samson-Himmelstjerna, Georg; Feldmeier, Hermann; Waiswa, Charles; Bukeka Muhindo, Jeanne; Krücken, Jürgen

    2016-01-01

    Background In endemic communities, zoonotic tungiasis, a severe skin disease caused by penetrating female sand fleas, is a public health hazard causing significant human and animal morbidity. No validated drugs are currently available for treatment of animal tungiasis. Due to the reservoir in domestic animals, integrated management of human and animal tungiasis is required to avert its negative effects. Methods and principal findings A topical aerosol containing chlorfenvinphos 4.8%, dichlorphos 0.75% and gentian violet 0.145% licensed to treat tick infestations, myiasis and wound sepsis in animals in the study area, was tested for its potential tungicidal effects in a randomized controlled field trial against pig tungiasis in rural Uganda. Animals with at least one embedded flea were randomized in a treatment (n = 29) and a control (n = 26) group. One week after treatment, 58.6% of the treated pigs did not show any viable flea lesion whereas all control pigs had at least one viable lesion. After treatment the number of viable lesions (treated median = 0, overall range = 0–18 vs. control median = 11.5, range = 1–180) and the severity score for estimating acute pathology in pig tungiasis (treated median = 1, range = 0–3.5 vs. control median = 7, range = 0–25) were significantly lower in treated than in control pigs (p < 0.001). In the treatment group the median number of viable flea lesions decreased from 8.5 to 0 (p < 0.001). Similarly, the median acute severity score dropped from 6 to 1 (p < 0.001). Every pig in the treatment group showed a decrease in the number of viable fleas and tungiasis-associated acute morbidity while medians for both increased in the control group. Conclusions The study demonstrates that a topical treatment based on chlorfenvinphos, dichlorphos and gentian violet is highly effective against pig tungiasis. Due to its simplicity, the new approach can be used for the treatment of individual animals as well as in mass campaigns. PMID

  6. ULTRA HIGH POWER TRANSMISSION LINE TECHNIQUES

    Science.gov (United States)

    The ultra-high power transmission line techniques including both failure mechanisms and component design are discussed. Failures resulting from...a waveguide. In view of the many advantages of the low loss mode in circular waveguide for ultra-high power levels, a mode transducer and a two...percent of the peak power of a standard rectangular wave guide. Water cooling is provided for high average power operation. Analysis of mode sup pression

  7. CMOS Compatible Ultra-Compact Modulator

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Kinsey, Nathaniel; Naik, Gururaj V.

    2014-01-01

    A planar layout for an ultra-compact plasmonic modulator is proposed and numerically investigated. Our device utilizes potentially CMOS compatible materials and can achieve 3-dB modulation in just 65nm and insertion loss <1dB at telecommunication wavelengths.......A planar layout for an ultra-compact plasmonic modulator is proposed and numerically investigated. Our device utilizes potentially CMOS compatible materials and can achieve 3-dB modulation in just 65nm and insertion loss

  8. Ultra wideband antennas design, methodologies, and performance

    CERN Document Server

    Galvan-Tejada, Giselle M; Jardón Aguilar, Hildeberto

    2015-01-01

    Ultra Wideband Antennas: Design, Methodologies, and Performance presents the current state of the art of ultra wideband (UWB) antennas, from theory specific for these radiators to guidelines for the design of omnidirectional and directional UWB antennas. Offering a comprehensive overview of the latest UWB antenna research and development, this book:Discusses the developed theory for UWB antennas in frequency and time domainsDelivers a brief exposition of numerical methods for electromagnetics oriented to antennasDescribes solid-planar equivalen

  9. Analysis of ultra-triathlon performances.

    Science.gov (United States)

    Lepers, Romuald; Knechtle, Beat; Knechtle, Patrizia; Rosemann, Thomas

    2011-01-01

    Despite increased interest in ultra-endurance events, little research has examined ultra-triathlon performance. The aims of this study were: (i) to compare swimming, cycling, running, and overall performances in three ultra-distance triathlons, double Ironman distance triathlon (2IMT) (7.6 km swimming, 360 km cycling, and 84.4 km running), triple Ironman distance triathlon (3IMT) (11.4 km, 540 km, and 126.6 km), and deca Ironman distance triathlon (10IMT) (38 km, 1800 km, and 420 km) and (ii) to examine the relationships between the 2IMT, 3IMT, and 10IMT performances to create predicted equations of the 10IMT performances. Race results from 1985 through 2009 were examined to identify triathletes who performed the three considered ultra-distances. In total, 73 triathletes (68 men and 5 women) were identified. The contribution of swimming to overall ultra-triathlon performance was lower than for cycling and running. Running performance was more important to overall performance for 2IMT and 3IMT compared with 10IMT The 2IMT and 3IMT performances were significantly correlated with 10IMT performances for swimming and cycling, but not for running. 10IMT total time performance might be predicted by the following equation: 10IMT race time (minutes) = 5885 + 3.69 × 3IMT race time (minutes). This analysis of human performance during ultra-distance triathlons represents a unique data set in the field of ultra-endurance events. Additional studies are required to determine the physiological and psychological factors associated with ultra-triathlon performance.

  10. Women in extreme poverty.

    Science.gov (United States)

    1994-01-01

    Population is estimated to increase from 5.5 billion in 1990 to 10 billion by 2050; the poverty level is expected to increase from 1 billion to 2-3 billion people. Women in development has been promoted throughout the UN and development system, but women in poverty who perform work in the informal sector are still uncounted, and solutions are elusive. The issue of extreme poverty can not be approached as just another natural disaster with immediate emergency relief. Many people live in precarious economic circumstances throughout their lives. Recent research reveals a greater understanding of the underlying causes and the need for inclusion of poor women in sustainable development. Sanitation, water, housing, health facilities need to be improved. Women must have access to education, opportunities for trading, and loans on reasonable terms. UNESCO makes available a book on survival strategies for poor women in the informal sector. The profile shows common problems of illiteracy, broken marriages, and full time involvement in provision of subsistence level existence. Existence is a fragile balance. Jeanne Vickers' "Women and the World" offers simple, low cost interventions for aiding extremely poor women. The 1992 Commission on the Status of Women was held in Vienna. Excerpts from several speeches are provided. The emphasis is on some global responses and an analysis of solutions. The recommendation is for attention to the gender dimension of poverty. Women's dual role contributes to greater disadvantages. Women are affected differently by macroeconomic factors, and that there is intergenerational transfer of poverty. Social services should be viewed as investments and directed to easing the burdens on time and energy. Public programs must be equipped to deal with poverty and to bring about social and economic change. Programs must be aware of the different distribution of resources within households. Women must be recognized as principal economic providers within

  11. Extreme winds in Denmark

    Energy Technology Data Exchange (ETDEWEB)

    Kristensen, L.; Rathmann, O.; Hansen, S.O.

    1999-02-01

    Wind-speed data from four sites in Denmark have been analyzed in order to obtain estimates of the basic wind velocity which is defined as the 50-year wind speed under standard conditions, i.e. ten-minute averages at the height 10 m over a uniform terrain with the roughness length 0.05 m. The sites are, from west, Skjern (15 years), Kegnaes (7 years), Sprogoe (20 years), and Tystofte (15 years). The data are ten minute averages of wind speed, wind direction, temperature and pressure. The last two quantities are used to determine the air density {rho}. The data are cleaned for terrain effects by means of a slightly modified WASP technique where the sector speed-up factors and roughness lengths are linearly smoothed with a direction resolution of one degree. Assuming geotropic balance, all the wind-velocity data are transformed to friction velocity u{sub *} and direction at standard conditions by means of the geotropic drag law for neutral stratification. The basic wind velocity in 30 deg. sectors are obtained through ranking of the largest values of the friction velocity pressure 1/2{rho}u{sub *}{sup 2} taken both one every two months and once every year. The main conclusion is that the basic wind velocity is significantly larger at Skjern, close to the west coast of Jutland, than at any of the other sites. Irrespective of direction, the present standard estimates of 50-year wind are 25 {+-} 1 m/s at Skern and 22 {+-} 1 m/s at the other three sites. These results are in agreement with those obtained by Jensen and Franck (1970) and Abild (1994) and supports the conclusion that the wind climate at the west coast of Jutland is more extreme than in any other part of the country. Simple procedures to translate in a particular direction sector the standard basic wind velocity to conditions with a different roughness length and height are presented. It is shown that a simple scheme makes it possible to calculate the total 50-year extreme load on a general structure without

  12. Ultra-spinning gauged supergravity black holes and their Kerr/CFT correspondence

    Science.gov (United States)

    Noorbakhsh, S. M.; Ghominejad, M.

    2017-02-01

    Recently a new class of asymptotically AdS ultra-spinning black holes has been constructed with a noncompact horizon of finite area [R. A. Hennigar, D. Kubiznak, and R. B. Mann, Super-Entropic Black Holes, Phys. Rev. Lett. 115, 031101 (2015)., 10.1103/PhysRevLett.115.031101], in which the asymptotic rotation is effectively boosted to the speed of light. We employ this technique for four-dimensional U (1 )4 and five-dimensional U (1 )3 gauged supergravity black holes. The obtained new exact black hole solutions for both cases possess a noncompact horizon; their topologies are a sphere with two punctures. We then demonstrate that the ultra-spinning limit commutes with the extremality condition as well as the near horizon limit for both black holes. We also show that the near horizon extremal geometries of the resulting ultra-spinning gauged supergravity black holes lead to the well-known result which contains an AdS2 throat. We then obtain the [(d -1 )/2 ] central charges of the dual CFTs. By assuming the Cardy formula, we show that despite the noncompactness of the horizon, microscopic entropy of the dual CFT is precisely equivalent to the Bekenstein-Hawking entropy.

  13. Stacked Extreme Learning Machines.

    Science.gov (United States)

    Zhou, Hongming; Huang, Guang-Bin; Lin, Zhiping; Wang, Han; Soh, Yeng Chai

    2015-09-01

    Extreme learning machine (ELM) has recently attracted many researchers' interest due to its very fast learning speed, good generalization ability, and ease of implementation. It provides a unified solution that can be used directly to solve regression, binary, and multiclass classification problems. In this paper, we propose a stacked ELMs (S-ELMs) that is specially designed for solving large and complex data problems. The S-ELMs divides a single large ELM network into multiple stacked small ELMs which are serially connected. The S-ELMs can approximate a very large ELM network with small memory requirement. To further improve the testing accuracy on big data problems, the ELM autoencoder can be implemented during each iteration of the S-ELMs algorithm. The simulation results show that the S-ELMs even with random hidden nodes can achieve similar testing accuracy to support vector machine (SVM) while having low memory requirements. With the help of ELM autoencoder, the S-ELMs can achieve much better testing accuracy than SVM and slightly better accuracy than deep belief network (DBN) with much faster training speed.

  14. Solar extreme events

    CERN Document Server

    Hudson, Hugh S

    2015-01-01

    Solar flares and CMEs have a broad range of magnitudes. This review discusses the possibility of "extreme events," defined as those with magnitudes greater than have been seen in the existing historical record. For most quantitative measures, this direct information does not extend more than a century and a half into the recent past. The magnitude distributions (occurrence frequencies) of solar events (flares/CMEs) typically decrease with the parameter measured or inferred (peak flux, mass, energy etc. Flare radiation fluxes tend to follow a power law slightly flatter than $S^{-2}$, where S represents a peak flux; solar particle events (SPEs) follow a still flatter power law up to a limiting magnitude, and then appear to roll over to a steeper distribution, which may take an exponential form or follow a broken power law. This inference comes from the terrestrial $^{14}$C record and from the depth dependence of various radioisotope proxies in the lunar regolith and in meteorites. Recently major new observation...

  15. Extremal almost-Kahler metrics

    CERN Document Server

    Lejmi, Mehdi

    2009-01-01

    We generalize the notion of the Futaki invariant and extremal vector field to the general almost-Kahler case and we prove the periodicity of the extremal vector field when the symplectic form represents an integral cohomology class modulo torsion. We give also an explicit formula of the hermitian scalar curvature which allows us to obtain examples of non-integrable extremal almost-Kahler metrics saturating LeBrun's estimates.

  16. Upper extremity amputations and prosthetics.

    Science.gov (United States)

    Ovadia, Steven A; Askari, Morad

    2015-02-01

    Upper extremity amputations are most frequently indicated by severe traumatic injuries. The location of the injury will determine the level of amputation. Preservation of extremity length is often a goal. The amputation site will have important implications on the functional status of the patient and options for prosthetic reconstruction. Advances in amputation techniques and prosthetic reconstructions promote improved quality of life. In this article, the authors review the principles of upper extremity amputation, including techniques, amputation sites, and prosthetic reconstructions.

  17. Post-column reaction for simultaneous analysis of chromatic and leuco forms of malachite green and crystal violet by high-performance liquid chromatography with photometric detection

    Science.gov (United States)

    Allen, J.L.; Meinertz, J.R.

    1991-01-01

    The chromatic and leuco forms of malachite green and crystal violet were readily separated and detected by a sensitive and selective high-performance liquid chromatographic procedure. The chromatic and leuco forms of the dyes were separated within 11 min on a C18 column with a mobile phase of 0.05 M sodium acetate and 0.05 M acetic acid in water (19%) and methanol (81%). A reaction chamber, containing 10% PbO2 in Celite 545, was placed between the column and the spectrophotometric detector to oxidize the leuco forms of the dyes to their chromatic forms. Chromatic and leuco malachite green were quantified by their absorbance at 618 nm; and chromatic and leuco Crystal Violet by their absorbance at 588 nm. Detection limits for chromatic and leuco forms of both dyes ranged from 0.12 to 0.28 ng. A linear range of 1 to 100 ng was established for both forms of the dyes.

  18. Room-temperature violet luminescence and ultraviolet photodetection of Sb-doped ZnO/Al-doped ZnO homojunction array.

    Science.gov (United States)

    Chen, Wei-Jen; Wu, Jen-Kai; Lin, Jheng-Cyuan; Lo, Shun-Tsung; Lin, Huang-De; Hang, Da-Ren; Shih, Ming Feng; Liang, Chi-Te; Chang, Yuan Huei

    2013-07-05

    A Sb-doped ZnO microrod array was fabricated on an Al-doped ZnO thin film by electrodeposition. Strong violet luminescence, originated from free electron-to-acceptor level transitions, was identified by temperature-dependent photoluminescence measurements. This acceptor-related transition was attributed to substitution of Sb dopants for Zn sites, instead of O sites, to form a complex with two Zn vacancies (VZn), the SbZn-2VZn complex. This SbZn-2VZn complex has a lower formation energy and acts as a shallow acceptor which can induce the observed strong violet luminescence. The photoresponsivity of our ZnO p-n homojunction device under a negative bias demonstrated a nearly 40-fold current gain, illustrating that our device is potentially an excellent candidate for photodetector applications in the ultraviolet wavelength region.

  19. Likelihood estimators for multivariate extremes

    KAUST Repository

    Huser, Raphaël

    2015-11-17

    The main approach to inference for multivariate extremes consists in approximating the joint upper tail of the observations by a parametric family arising in the limit for extreme events. The latter may be expressed in terms of componentwise maxima, high threshold exceedances or point processes, yielding different but related asymptotic characterizations and estimators. The present paper clarifies the connections between the main likelihood estimators, and assesses their practical performance. We investigate their ability to estimate the extremal dependence structure and to predict future extremes, using exact calculations and simulation, in the case of the logistic model.

  20. A new rapid colourimetric method for testing Mycobacterium tuberculosis susceptibility to isoniazid and rifampicin: a crystal violet decolourisation assay

    Directory of Open Access Journals (Sweden)

    Ahmet Yilmaz Coban

    2014-04-01

    Full Text Available The aim of this study was to investigate the performance of a new and accurate method for the detection of isoniazid (INH and rifampicin (RIF resistance among Mycobacterium tuberculosis isolates using a crystal violet decolourisation assay (CVDA. Fifty-five M. tuberculosis isolates obtained from culture stocks stored at -80ºC were tested. After bacterial inoculation, the samples were incubated at 37ºC for seven days and 100 µL of CV (25 mg/L stock solution was then added to the control and sample tubes. The tubes were incubated for an additional 24-48 h. CV (blue/purple was decolourised in the presence of bacterial growth; thus, if CV lost its colour in a sample containing a drug, the tested isolate was reported as resistant. The sensitivity, specificity, positive predictive value, negative predictive value and agreement for INH were 92.5%, 96.4%, 96.1%, 93.1% and 94.5%, respectively, and 88.8%, 100%, 100%, 94.8% and 96.3%, respectively, for RIF. The results were obtained within eight-nine days. This study shows that CVDA is an effective method to detect M. tuberculosis resistance to INH and RIF in developing countries. This method is rapid, simple and inexpensive. Nonetheless, further studies are necessary before routine laboratory implementation.