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Sample records for 3-5 micron spectrum

  1. The 3.5 micron light curves of long period variable stars. Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Strecker, D. W.

    1973-01-01

    Infrared observations at an effective wavelength of 3.5 microns of a selected group of long period variable (LPV) stars are presented. Mira type and semiregular stars of M, S, and C spectral classifications were monitored throughout the full cycle of variability. Although the variable infrared radiation does not exactly repeat in intensity or time, the regularity is sufficient to produce mean 3.5 micron light curves. The 3.5 micron maximum radiation lags the visual maximum by about one-seventh of a cycle, while the minimum 3.5 micron intensity occurs nearly one-half cycle after infrared maximum. In some stars, there are inflections or humps on the ascending portion of the 3.5 micron light curve which may also be seen in the visual variations.

  2. Exploratory 5-micron spectrum of Uranus

    SciTech Connect

    Orton, G.S.; Kaminski, C.D.

    1989-01-01

    The intensity peak at 4.8 microns characterizing the spectrum observed for the disk of Uranus near 5 microns, in June 1987, exhibits steep declines at shorter and longer wavelength. An exploratory discussion is presented of various models in view of these data; it is noted that some component of the radiation must originate near the 140 K atmospheric irrespective of the radiation's origin in sunlight or thermal emission; physical considerations dictate that it be at least partly thermal in origin. One model consistent with the data requires the presence of a cloud top at the 8-bar level. 30 references.

  3. Infrared spectrum of Io, 2.8-5.2 microns

    NASA Astrophysics Data System (ADS)

    Cruikshank, D. P.

    1980-02-01

    The reflectance spectrum of Io is presented from 2.8 to 5.2 microns demonstrating the full extent of the broad and deep spectral absorption between 3.5 and 4.8 microns. Laboratory spectra of nitrates and carbonates diluted with sulfur do not satisfactorily reproduce the Io spectrum, but new information based on recently discovered volcanic activity on the satellite lead to consideration of other classes of compounds reported by Fanale et al. (1979). It is concluded that the variability of the supply of condensible SO2 gas to the surface of Io, its removal by sublimination, and the temporal variations in the strength of the SO2 band may provide an index of volcanic activity on Io that can be monitored from the earth.

  4. High-resolution IRCCD images of the Galactic center at 2.2 and 3.5 microns

    NASA Technical Reports Server (NTRS)

    Tollestrup, Eric V.; Becklin, E. E.; Capps, Richard W.

    1989-01-01

    An IRCCD camera was used to obtain high-resolution images at 2.2 and 3.5 microns of the Galactic center at subarcsecond resolution. These images show that the compact nonthermal radio source Sgr A-asterisk is not coincident with any part of IRS 16; Sgr A-asterisk is found to be 1.1 + or - 0.3 arcsec west of IRS 16C. At 3.5 microns, IRS 16 is a complex object. IRS 16SW is resolved into two sources, and IRS 16C may be double or extended. From the colors and sizes of the various components, it is difficult to explain these objects as stellar clusters; the required stellar density would be too high. Finally, there is evidence that there is a blue and a red source, separated by about 1 arcsec, for each of the northern arm sources, IRS 1W, IRS 5, and IRS 10.

  5. Clio: a 3-5 micron AO planet-finding camera

    NASA Astrophysics Data System (ADS)

    Sivanandam, Suresh; Hinz, Phil M.; Heinze, Ari N.; Freed, Melanie; Breuninger, Andrew H.

    2006-06-01

    Clio is an adaptive-optics camera mounted on the 6.5 meter MMT optimized for diffraction-limited L' and M-band imaging over a ~ 15" field. The instrument was designed from the ground up with a large well-depth, fast readout thermal infrared (~ 3_5μm) 320 by 256 pixel InSb detector, cooled optics, and associated focal plane and pupil masks (with the option for a coronograph) to minimize the thermal background and maximize throughput. When coupled with the MMT's adaptive secondary AO (two warm reflections) system's low thermal background, this instrument is in a unique position to image nearby warm planets, which are the brightest in the L' and M-band atmospheric windows. We present the current status of this recently commissioned instrument that performed exceptionally during first light. Our instrument sensitivities are impressive and are sky background limited: for an hour of integration, we obtain an L'-band 5 σ detection limit of of 17.0 magnitudes ~ 80%) and an M-band limit of 14.5 (Strehl ~ 90%). Our M-band sensitivity is lower due to the increase in thermal sky background. These sensitivities translate to finding relatively young planets five times Jupiter mass (M Jup) at 10 pc within a few AU of a star. Presently, a large Clio survey of nearby stellar systems is underway including a search for planets around solar-type stars, M dwarfs, and white dwarfs. Even with a null result, we can place strong constraints on planet distribution models.

  6. The 1.7- to 4.2-micron spectrum of asteroid 1 Ceres - Evidence for structural water in clay minerals

    NASA Technical Reports Server (NTRS)

    Lebofsky, L. A.; Feierberg, M. A.; Larson, H. P.; Johnson, J. R.; Tokunaga, A. T.

    1981-01-01

    A high-resolution Fourier spectrum (1.7-3.5 microns) and medium-resolution spectrophotometry (2.7-4.2 microns) were obtained for Asteroid 1 Ceres. The presence of the 3-micron absorption feature due to water of hydration was confirmed. The 3-micron feature is compared with the 3-micron bands due to water of hydration in clays and salts. It is concluded that the spectrum of Ceres shows a strong absorption at 2.7-2.8 microns due to structural OH groups in clay minerals. The dominant minerals on the surface of Ceres are therefore hydrated clay minerals structurally similar to terrestrial montmorillonites. There is also a narrow absorption feature at 3.1 microns which is attributable to a very small amount of water ice on Ceres. This is the first evidence for ice on the surface of an asteroid.

  7. Bidirectional reflectance measurement of zinc oxide in 0.25 to 2.5 microns spectrum

    NASA Technical Reports Server (NTRS)

    Scott, R. L., Jr.

    1974-01-01

    An experimental apparatus was designed and used to measure the bidirectional reflectance of zinc oxide in the spectrum 0.25 to 2.5 microns. The nonspecular reflectance is essentially Lambert for wavelengths above 0.40 microns with the most deviation occuring for large source zenith angles. Below 0.400 microns the nonspecular reflectance is greater than Lambert in all directions and is greatest in the forward and backscatter directions. The ratio of the specular component to the nonspecular component at a zenith of 0 degrees was found to increase with source zenith and wavelength for wavelengths above 0.400 microns. Below 0.400 microns this ratio increases as wavelengths decrease. The variation of bidirectional reflectance with wavelength was found to have the characteristics absorption for Zn0 for wavelength below 0.400 microns.

  8. Modeling the reflectance spectrum of Callisto 0.25 to 4.1 microns

    NASA Astrophysics Data System (ADS)

    Calvin, W. M.; Clark, R. N.

    1991-02-01

    Models employing Hapke's (1981) radiative transfer theory are presented for the 0.2-4.1 micron reflectance spectrum. A simultaneous intimate, as well as aereal, mixture solution of ice and dark material is envisioned, in order to satisfy both absorption band depths and reflectance levels. The models indicate that the surface's ice component is rather large-grained, and that the major spectral features above about 2.5 microns cannot be accounted for by the ice. Spectra obtained for the nonice material were similar to each other; their absorption features resemble hydrated silicates bearing both oxidation states of iron.

  9. Emission features in the spectrum of NGC 7027 near 3. 3 microns at very high resolution

    SciTech Connect

    Lowe, R.P.; Moorhead, J.M.; Wehlau, W.H.; Maillard, J.P. CNRS, Institut d'Astrophysique, Paris )

    1991-02-01

    A very high resolution spectrum is presented of the planetary nebula NGC 7027 over a 200/cm interval centered at 2950/cm, and the features found are described: (1) nebular continuum, (2) atomic recombination lines of H and He II, and (3) three broader emission features of uncertain origin. For the latter the first evidence is presented that the 3.46 micron feature and possibly the 3.40 micron feature are resolvable into a sequence of narrower features. The interpretation of the broader features is discussed in terms of the hypothesis of identification with emission by polycyclic aromatic hydrocarbons. 18 refs.

  10. Modeling the reflectance spectrum of Callisto 0. 25 to 4. 1 microns

    SciTech Connect

    Calvin, W.M.; Clark, R.N. )

    1991-02-01

    Models employing Hapke's (1981) radiative transfer theory are presented for the 0.2-4.1 micron reflectance spectrum. A simultaneous intimate, as well as aereal, mixture solution of ice and dark material is envisioned, in order to satisfy both absorption band depths and reflectance levels. The models indicate that the surface's ice component is rather large-grained, and that the major spectral features above about 2.5 microns cannot be accounted for by the ice. Spectra obtained for the nonice material were similar to each other; their absorption features resemble hydrated silicates bearing both oxidation states of iron. 33 refs.

  11. Modeling the reflectance spectrum of Callisto 0.25 to 4.1 microns

    NASA Technical Reports Server (NTRS)

    Calvin, Wendy M.; Clark, Roger N.

    1991-01-01

    Models employing Hapke's (1981) radiative transfer theory are presented for the 0.2-4.1 micron reflectance spectrum. A simultaneous intimate, as well as aereal, mixture solution of ice and dark material is envisioned, in order to satisfy both absorption band depths and reflectance levels. The models indicate that the surface's ice component is rather large-grained, and that the major spectral features above about 2.5 microns cannot be accounted for by the ice. Spectra obtained for the nonice material were similar to each other; their absorption features resemble hydrated silicates bearing both oxidation states of iron.

  12. The 2.4 micron spectrum of Comet Halley - A search for H2 emission

    NASA Astrophysics Data System (ADS)

    Smith, W. H.; Wolstencroft, R. D.; Lutz, B. L.

    1989-02-01

    A 2.4-micron spectrum of Comet Halley was obtained on April 1, 1986 with the UKIRT scanning Fabry-Perot-CVF equipped with an InSb detector. From the ratio of the measured flux from comet Halley to Zeta Her in the 8.8 x 10 to the -4th micron bandwidth, Comet Halley produced a detected flux of about 1.3 x 10 to the 5th photons/sec with a 1-sigma variance of 385 photons. The flux detected in the same spectral region by Maillard et al. (1986) agrees with the measurements reported here to within a factor of two. The data obtained are examined from the standpoint of the possible mechanisms of H2 production.

  13. The 3 micron spectrum of the classical Be star Beta Monocerotis A

    NASA Technical Reports Server (NTRS)

    Sellgren, K.; Smith, R. G.

    1992-01-01

    A 3.1-3.7-micron spectrum of the classical Be star Beta Mon A is presented at a resolution of lambda/Delta-lambda of 700-800. The spectrum shows strong hydrogen recombination lines, including Pf-delta and a series of Humphreys lines from Hu 19 to Hu 28. The relative recombination line strengths suggest that Pf-delta has a large optical depth. The Humphreys lines have relative strengths consistent with case B and may be optically thin. The line widths observed are broader than the Balmer lines and similar in width to Fe II lines, consistent with a disk model in which optically thinner lines arise primarily from a faster rotating inner disk, while optically thicker lines come mainly from a slower rotating outer disk. The apparent lack of Stark broadening of the Humphreys lines is used to place an upper limit on the circumstellar electron density of about 10 exp 12/cu cm.

  14. Investigations on the 1.7 micron residual absorption feature in the vegetation reflection spectrum

    NASA Technical Reports Server (NTRS)

    Verdebout, J.; Jacquemoud, S.; Andreoli, G.; Hosgood, B.; Sieber, A.

    1993-01-01

    The detection and interpretation of the weak absorption features associated with the biochemical components of vegetation is of great potential interest to a variety of applications ranging from classification to global change studies. This recent subject is also challenging because the spectral signature of the biochemicals is only detectable as a small distortion of the infrared spectrum which is mainly governed by water. Furthermore, the interpretation is complicated by complexity of the molecules (lignin, cellulose, starch, proteins) which contain a large number of different and common chemical bonds. In this paper, we present investigations on the absorption feature centered at 1.7 micron; these were conducted both on AVIRIS data and laboratory reflectance spectra of leaves.

  15. Detection of the 2165 Inverse Centimeter (4.619 Micron) XCN Band in the Spectrum of L1551 IRS 5

    NASA Technical Reports Server (NTRS)

    Tegler, Stephen C.; Weintraub, David A.; Allamandola, Louis J.; Sandford, Scott A.; Rettig, Terrence W.; Campins, Humberto

    1993-01-01

    We report the detection of a broad absorption band at 2165 cm (4.619 microns) in the spectrum of L1551 IRS 5. New laboratory results over the 2200-2100 /cm wavenumber interval (4.55-4.76 microns), performed with realistic interstellar ice analogs, suggest that this feature is due to a CN-containing compound. We will refer to this compound as XCN. We also confirm the presence of frozen CO (both in nonpolar and polar matrices) through absorption bands at 2140 /cm (4.67 microns) and 2135 /cm (4.68 microns). The relative abundance of solid-state CO to frozen H2O is approx. 0.13 while the abundance of XCN seems comparable to that of frozen CO.

  16. The Infrared Spectrum of H2S From 1 to 5 Microns

    NASA Technical Reports Server (NTRS)

    Bykov, Alexander D.; Naumenko, Olga V.; Smirnov, Maxim A.; Sinitsa, Leonid N.; Brown, Linda R.; Crisp, Joy; Crisp, David

    1994-01-01

    The absorption spectra of H2S from 2000 to 11,147 cm(exp -1) have been obtained with spectral resolutions of 0.006, 0.012, and 0.021 cm(exp -1) using the Fourier transform spectrometer at Kitt Peak National Observatory. The transitions of 21 bands have been assigned for the first time and 9 others reanalyzed so that accurate energy levels, band origins, and rotational parameters could be determined. The analysis of these data revealed some remarkable features in the energy spectrum, e.g., fourfold clustering of rotational levels belonging to the symmetric and asymmetric components of local mode manifolds at a high degree of stretching excitation. This paper reports fitted vibrational parameters and predicted band origins of H2S-32 up to 12,735 cm(exp -1). It also presents the degenerate rotational constants and upper state energies of (301)-(202) and (311)-(212) at 1 micron as illustrations of clustering in the local mode limit.

  17. The temporal evolution of the 4-14 micron spectrum of V1974 Cygni (Nova Cygni 1992)

    NASA Technical Reports Server (NTRS)

    Gehrz, R. D.; Woodward, Charles E.; Greenhouse, M. A.; Starrfield, S.; Wooden, D. H.; Witteborn, F. C.; Sanford, S. A.; Allamandola, L. J.; Bregman, J. D.; Klapisch, M.

    1994-01-01

    We present 4-14 micron spectra of the ONeMg nova V1974 Cygni (Nova Cygni 1992) obtained during 1992 May on the NASA Kuiper Airborne Observatory (KAO) and from the NASA 1.52 m infrared telescope at Mount Lemmon, Arizona in 1992 October/November with the HIFOGS mid-infrared spectrometer. The spectra at both epochs showed continuum emission from thermal bremstrahlung (free-free radiation) with emission lines from hydrogen and (Ne II), (Ar III), and Ne VI). During May, approximately = 80 days after outburst, the dominant emission lines in the mid-infrared spectra were a blend of three lines (Pf-alpha, Hu-beta, H11-7) near 7.5 microns and (Ne II) at 12.8 microns. By October (approximately 160 days later), the hydrogen emission had virtually disappeared, the (Ne II) 12.8 micron line had weakened considerably, and a pronounced (Ne VI) emission line had appeared at 7.6 microns. This behavior confirms that V1974 Cyg is similar to the prototypical slow ONeMg 'neon nova', Nova QU Vulpeculae (1984 No. 2). The remarkable evolution of the spectrum suggests that the ionization conditions changed drastically between 1992 May and 1992 October. We find that the ejecta of V1974 Cyg were overabundant in neon with respect to silicon by a factor of approximately 10 relative to the solar photosphere. We present new model calculations of infrared sodium forbidden line emission from (Na III) 7.319 microns (Na IV) 9.039 microns, and (Na IV) 21.29 microns that can be compared with recent model predictions of sodium synthesis in ONeMg nova outbursts. We conclude that sodium abundances in ONeMg novae can be determined by observations of infrared coronal lines of sodium that are accssible to the Infrared Space Observatory (ISO) and instruments at the NASA Infrared Telescope Facility (IRTF).

  18. Microwave spectrum and structure of the 3,5-difluoropyridine⋯CO2 van der Waals complex

    NASA Astrophysics Data System (ADS)

    Dewberry, Christopher T.; Cornelius, Ryan D.; Mackenzie, Rebecca B.; Smith, C. J.; Dvorak, Michael A.; Leopold, Kenneth R.

    2016-10-01

    The rotational spectrum of the weakly bound complex 3,5-difluoropyridine⋯CO2 has been observed using pulsed-nozzle Fourier transform microwave spectroscopy. Spectroscopic constants are reported for the parent and 13CO2 isotopologues. The data indicate a planar structure in which the nitrogen approaches the carbon of the CO2 with either a C2v or effectively C2v geometry in the ground vibrational state. The N⋯C van der Waals bond distance is 2.8245(16) Å and the oxygen⋯ortho-hydrogen distance is 3.091(2) Å. The N⋯C van der Waals bond length is 0.027(8) Å longer than that previously determined for pyridine-CO2, but is still considerably shorter than the 2.998 Å distance in HCN⋯CO2. M06-2X/6-311++G(3df,3pd) calculations place the binding energy of the complex at 4.3 kcal/mol (4.1 kcal/mol with counterpoise correction). The calculations further indicate that a secondary interaction between the ortho-hydrogens of the ring and the CO2 oxygens account for ∼50% of the total binding energy.

  19. Silicon monoxide in the 4 micron infrared spectrum of long-period variables

    NASA Technical Reports Server (NTRS)

    Hinkle, K. H.; Barnes, T. G.; Lambert, D. L.; Beer, R.

    1976-01-01

    The first-overtone sequence of vibration-rotation transitions of the free radical silicon monoxide are shown to have extreme phase-dependent variations in the spectra of two M-type long-period variables, Omicron Ceti and R Leonis, and the mild S-type long-period variable, Chi Cygni. At maximum light, the SiO band heads are not detectable. Near minimum light, the band heads of (Si-25)O are detected in the 4-micron spectra of all three stars. The band heads of the terrestrially less abundant isotopic species, (Si-29)O and (Si-30)O, are detected in Chi Cygni. Possible explanations of the phase-dependent behavior are discussed, and the role of the stellar chromosphere is considered.

  20. Ultraviolet photometry from the Orbiting Astronomical Observatory. XXXIX - The structure of the eclipsing Wolf-Rayet binary V444 Cygni as derived from light curves between 2460 A and 3. 5 microns

    NASA Technical Reports Server (NTRS)

    Cherepashchuk, A. M.; Khaliullin, Kh. F.; Eaton, J. A.

    1984-01-01

    The WN5 component of V444 Cyg is characterized on the basis of light curves constructed using 1971 OAO observations at 425, 332, 298, and 246 nm and the broadband data at 2.2 and 3.5 microns of Hartmann (1978). Data and calculation results are presented in tables and graphs and discussed. Parameters estimated include core radius 2.9 solar radii, surface temperature 90,000 K, surface electron density 9 x 10 to the 12th/cu cm, surface outflow velocity 400 km/s, and terminal velocity (at about 10 solar radii) 2500 km/s, suggesting that the flow is He. These results are found to agree with the model of Wolf-Rayet atmospheres proposed by Beals (1929, 1944).

  1. The spectrum of Phobos from Phobos 2 observations at 0.3-2.6 microns: Comparison to previous data and meteorite analogs

    NASA Technical Reports Server (NTRS)

    Murchie, Scott; Erard, Stephane

    1993-01-01

    The surface of Phobos has been proposed to consist of carbonaceous chondrite or optically darkened ordinary chondrite ('black chondrite'). Measurements of Phobos's spectrum are key evidence for testing these hypotheses. Disk-integrated measurements were obtained by the Mariner 9 UV spectrometer, Viking Lander cameras, and groundbased observations. In 1989 disk-resolved measurements of Phobos and Mars were obtained by three instruments on Phobos 2: the KRFM spectrometer, which covered the wavelength range 0.32 - 0.6 microns; the ISM imaging spectrometer, which covered the wavelength range 0.76 - 3.16 microns; and the VSK TV cameras, whose wavelength ranges overlap those of KRFM and ISM. Here we report analysis of the Phobos 2 measurements completed since earlier results were reported. We validated calibration of the Phobos measurements using observations of Mars for reference, and compared them with pre-1989 measurements. We also combined spectra from the three detectors to produce an integrated spectrum of Phobos from 0.3 - 2.6 microns. Phobos 2 results agree well with previous measurements, contrary to some reports. The general shape of the spectrum is consistent with both proposed analogues. However position and depth of the previously unobserved 1 micron absorption are more diagnostic, and indicate the composition of typical surfaces to be more consistent with black chondrite.

  2. Rotational Spectrum and Large Amplitude Motions of 3,4-, 2,5- and 3,5-DIMETHYL-BENZALDEHYDE

    NASA Astrophysics Data System (ADS)

    Kleiner, I.; Tudorie, M.; Jahn, M.; Grabow, J.-U.; Goubet, M.

    2012-06-01

    The microwave spectra of the 3,4-, 2,5- and 3,5-Dimethyl-Benzaldehyde (DMBA) molecules have been recorded for the first time in the 2-26.5 GHz frequency range, using the COBRA-FTMW spectrometer in Hannover, with an instrumental uncertainty of 0.5 kHz for unblended lines. The experimental assignments and fits are supplemented by ab initio quantum chemical calculations,conformational energy landscape, and dipole moment components. The analysis of the spectra for the three isomers are in progress. The latest results, including spectroscopic constants and large amplitude motion parameters, will be presented. This investigation follows the study of the spectra of the 4-Methyl-Benzaldehyde molecule. The DMBA isomers belong to a similar series of molecules formally obtained by adding a second methyl group at the aromatic ring. These molecules serve as prototype systems for the development of the theoretical model of asymmetric top molecules having Cs symmetry while containing two inequivalent methyl tops (C3v), exhibiting different barrier heights and coupling terms to methyl internal rotation. Thus, the DMBA isomers represent benchmark species for testing the two-top internal rotors BELGI program written recently. Supported by the ANR-08-BLAN-0054 contract (France), the Deutsche Forschungsgemeinschaft, and the Land Niedersachsen (Germany). H. Saal, W. Caminati, I. Kleiner, A. R. Hight-Walker, J. T. Hougen, J.-U. Grabow, to be published. M. Tudorie, I. Kleiner, J. T. Hougen, S. Melandri, L. W. Sutikdja, W. Stahl, J. Mol. Spectrosc., 269 (2011), 211-225

  3. Absolute integrated intensity and individual line parameters for the 6.2-micron band of NO2. [in solar spectrum

    NASA Technical Reports Server (NTRS)

    Goldman, A.; Bonomo, F. S.; Williams, W. J.; Murcray, D. G.; Snider, D. E.

    1975-01-01

    The absolute integrated intensity of the 6.2-micron band of NO2 at 40 C was determined from quantitative spectra at about 10 per cm resolution by the spectral band model technique. A value of 1430 plus or minus 300 per sq cm per atm was obtained. Individual line parameters, positions, intensities, and ground-state energies were derived, and line-by-line calculations were compared with the band model results and with the quantitative spectra obtained at about 0.5 per cm resolution.

  4. The detection of a new strong band near 3590 cm(exp -1) (2.79 microns) in the spectrum of Io

    NASA Technical Reports Server (NTRS)

    Salama, F.; Allamandola, L. J.; Sandford, S. A.; Bregman, Jesse D.; Witteborn, F. C.; Cruikshank, D. P.

    1995-01-01

    A strong absorption band at 3590 +/- 20 cm(exp -1) (2.790 +/- 0.015 microns) has been discovered in the spectrum of Io using the Kuiper Airborne Observatory (KAO). The 2 nu(sub 1) + nu(sub 3) combination mode of solid SO2 falls at this position. Since SO2 is abundant on Io it must contribute to the new band. However, a band due to H2O was also predicted near this frequency in Io's spectrum based on laboratory experiments of H2O:SO2 mixed Io ice analogs which were used to assign the two weak, variable features at 3370 and 3170 cm(exp -1) (2.97 and 3.15 microns) to trace amounts of H2O frozen in solid SO2 on Io. The new band probably originates from both SO2 and H2O. Unfortunately, the spectral resolution of the data is insufficient to settle the issue of whether or not there are two resolvable components.

  5. Laboratory studies of the newly discovered infrared band at 4705.2/cm (2.1253 microns) in the spectrum of Io - The tentative identification of CO2

    NASA Technical Reports Server (NTRS)

    Sandford, Scott A.; Salama, Farid; Allamandola, Louis J.; Trafton, Larry M.; Lester, Dan F.

    1991-01-01

    The present evaluation of results from over 120 laboratory experiments relevant to the Trafton et al. (1991) discovery of a 2.1253-micron line in the spectrum of Io demonstrates that this band is produced by neither overtones nor combinations of the fundamental bands of molecules already noted on Io. Since the band's frequency is close to the first overtone of the nu(3) asymmetric stretching mode of CO2, attention is given this molecule's behavior under Io conditions. While pure solid CO2, and CO2 intimately mixed in a matrix of solid SO2 and H2S, generate bands of similar widths, these fall at frequencies lower than the Io band. Attention is given to the possible identification of the Io band with CO2 multimers of 'clusters' on Io.

  6. Detection of the 2165 inverse centimeter (4.619 micron) XCN band in the spectrum of L1551 IRS 5

    NASA Technical Reports Server (NTRS)

    Tegler, Stephen C.; Weintraub, David A.; Allamandola, Louis J.; Sandford, Scott A.; Rettig, Terrence W.; Campins, Humberto

    1993-01-01

    We report the detection of a broad absorption band at 2165/cm in the spectrum of L1551 IRS 5. New laboratory results over the 2200-2100/cm wavenumber interval, performed with realistic interstellar ice analogs, suggest that this feature is due to a CN-containing compound. We will refer to this compound as XCN. We also confirm the presence of frozen CO through absorption bands at 2140/cm and 2135/cm. The relative abundance of solid state CO to frozen H2O is about 0.13 while the abundance of XCN seems comparable to that of frozen CO.

  7. High Excitation Rydberg Levels of Fe I from the ATMOS Solar Spectrum at 2.5 and 7 microns

    NASA Technical Reports Server (NTRS)

    Schoenfeld, W. G.; Chang, E. S.; Geller, M.; Johansson, S.; Nave, G.; Sauval, A. J.; Grevesse, N.

    1995-01-01

    The quadrupole-polarization theory has been applied to the 3d(sup 6)4S(D-6)4f and 5g subconfigurations of Fe I by a parametric fit, and the fitted parameters are used to predict levels in the 6g and 6h subconfigurations. Using the predicted values, we have computed the 4f-6g and 5g-6h transition arrays and made identifications in the ATMOS infrared solar spectrum. The newly identified 6g and 6h levels, based on ATMOS wavenumbers, are combined with the 5g levels and found to agree with the theoretical values with a root mean-squared-deviation of 0.042/ cm. Our approach yields a polarizability of 28.07 a(sub o, sup 2) and a quadrupole moment of 0.4360 +/- 0.0010 ea(sup 2, sub o) for Fe II, as well as an improved ionization potential of 63737.700 +/- 0.010/ cm for Fe I.

  8. 1 to 2.4 microns spectrum and orbital properties of the Giant Planet Beta Pictoris b obtained with the Gemini Planet Imager

    NASA Astrophysics Data System (ADS)

    Pueyo, Laurent; Chilcote, Jeffrey; Millar-Blanchaer, Max; Barman, Travis; Fitzgerald, Michael P.; Graham, James R.; Larkin, James; Kalas, Paul G.; dawson, Rebekah; Wang, Jason; Perrin, Marshall; Moon, Dae-Sik; Macintosh, Bruce

    2015-12-01

    We present a low-resolution multi-band spectrum of the planetary companion to the nearby young star beta Pictoris using the Gemini Planet Imager (GPI). GPI is designed to image and provide low-resolution spectra of Jupiter sized, self-luminous planetary companions around young nearby stars. While H-bandis the primary workhorse for the GPI Exoplanet Survey, the instrument is capable of observing in the near infrared covering Y, J, H, and K bands. These observations of Beta Pic Pictoris b were taken covering multiple bands as part of GPI’s verification and commissioning phase in 2013 and 2014. Using atmospheric models along with the H-band data we recently reported an effective temperature of 1600-1700 K and a surface gravity of log (g) = 3.5-4.5 (cgs units). A similar exercise was also carried out by an independent team using the J band data, and did yield similar conclusions. These values agree well with ”hot-start” predictions from planetary evolution models for a gas giant with mass between 10 and 12 M Jup and age between 10 and 20 Myr. Here we revisit these conclusions in light of a joint analysis of these two datasets along with the longer wavelength GPI spectrum in K band, and present refined constraints on the atmospheric properties of this giant planet. In addition, we present an updated orbit for Beta Pictoris b based on astrometric measurements taken using commissioning and subsequent monitoring observations, spanning 14 months. The planet has a semi-major axis of 9.2 (+1.5 -0.4) AU, with an eccentricity e≤ 0.26. The position angle of the ascending node is Ω=31.75 deg±0.15, offset from both the outer main disk and the inner disk seen in the GPI image. We finally discuss these properties in the context of planet-disk dynamical interactions.

  9. THE 3-5 {mu}m SPECTRUM OF NGC 1068 AT HIGH ANGULAR RESOLUTION: DISTRIBUTION OF EMISSION AND ABSORPTION FEATURES ACROSS THE NUCLEAR CONTINUUM SOURCE

    SciTech Connect

    Geballe, T. R.; Mason, R. E.; Rodriguez-Ardila, A.; Axon, D. J.

    2009-08-20

    We report moderate resolution 3-5 {mu}m spectroscopy of the nucleus of NGC 1068 obtained at 0.''3 (20 pc) resolution with the spectrograph slit aligned approximately along the ionization cones of the active galactic nucleus. The deconvolved full width at half-maximum of the nuclear continuum source in this direction is 0.''3. Four coronal lines of widely different excitations were detected; the intensity of each peaks near radio knot C, approximately 0.''3 north of the infrared continuum peak, where the radio jet changes direction. Together with the broadened line profiles observed near that location, this suggests that shock ionization is the dominant excitation mechanism of the coronal lines. The depth of the 3.4 {mu}m hydrocarbon absorption is maximum at and just south of the continuum peak, similar to the 10 {mu}m silicate absorption. That and the similar and rapid variations of the optical depths of both features across the nucleus suggest that substantial portions of both arise in a dusty environment just in front of the continuum source(s). A new and tighter limit is set on the column density of CO. Although clumpy models of the dust screen might explain the shallowness of the silicate feature, the presence of the 3.4 {mu}m feature and the absence of CO are strongly reminiscent of Galactic diffuse cloud environments and a consistent explanation for them and the observed silicate feature is found if all three phenomena occur in such an environment, existing as close as 10 pc to the central engine.

  10. Functional characterization of FABP3, 5 and 7 gene variants identified in schizophrenia and autism spectrum disorder and mouse behavioral studies

    PubMed Central

    Shimamoto, Chie; Ohnishi, Tetsuo; Maekawa, Motoko; Watanabe, Akiko; Ohba, Hisako; Arai, Ryoichi; Iwayama, Yoshimi; Hisano, Yasuko; Toyota, Tomoko; Toyoshima, Manabu; Suzuki, Katsuaki; Shirayama, Yukihiko; Nakamura, Kazuhiko; Mori, Norio; Owada, Yuji; Kobayashi, Tetsuyuki; Yoshikawa, Takeo

    2014-01-01

    Disturbances of lipid metabolism have been implicated in psychiatric illnesses. We previously reported an association between the gene for fatty acid binding protein 7 (FABP7) and schizophrenia. Furthermore, we identified and reported several rare non-synonymous polymorphisms of the brain-expressed genes FABP3, FABP5 and FABP7 from schizophrenia and autism spectrum disorder (ASD), diseases known to part share genetic architecture. Here, we conducted further studies to better understand the contribution these genes make to the pathogenesis of schizophrenia and ASD. In postmortem brains, we detected altered mRNA expression levels of FABP5 in schizophrenia, and of FABP7 in ASD and altered FABP5 in peripheral lymphocytes. Using a patient cohort, comprehensive mutation screening identified six missense and two frameshift variants from the three FABP genes. The two frameshift proteins, FABP3 E132fs and FABP7 N80fs, formed cellular aggregates and were unstable when expressed in cultured cells. The four missense mutants with predicted possible damaging outcomes showed no changes in intracellular localization. Examining ligand binding properties, FABP7 S86G and FABP7 V126L lost their preference for docosahexaenoic acid to linoleic acid. Finally, mice deficient in Fabp3, Fabp5 and Fabp7 were evaluated in a systematic behavioral test battery. The Fabp3 knockout (KO) mice showed decreased social memory and novelty seeking, and Fabp7 KO mice displayed hyperactive and anxiety-related phenotypes, while Fabp5 KO mice showed no apparent phenotypes. In conclusion, disturbances in brain-expressed FABPs could represent an underlying disease mechanism in a proportion of schizophrenia and ASD sufferers. PMID:25027319

  11. The discovery of a new infrared emission feature at 1905 wavenumbers (5.25 microns) in the spectrum of BD +30 degrees 3639 and its relation to the polycyclic aromatic hydrocarbon model

    NASA Technical Reports Server (NTRS)

    Allamandola, L. J.; Bregman, J. D.; Sandford, S. A.; Tielens, A. G.; Witteborn, F. C.; Wooden, D. H.; Rank, D.

    1989-01-01

    We have discovered a new IR emission feature at 1905 cm-1 (5.25 microns) in the spectrum of BD +30 degrees 3639. This feature joins the family of well-known IR emission features at 3040, 2940, 1750, 1610, "1310," 1160, and 890 cm-1 (3.3, 3.4, 5.7, 6.2, "7.7," 8.6, and 11.2 microns). The origin of this new feature is discussed and it is assigned to an overtone or combination band involving C-H bending modes of polycyclic aromatic hydrocarbons (PAHs). Laboratory work suggests that spectral studies of the 2000-1650 cm-1 (5.0-6.1 microns) region may be very useful in elucidating the molecular structure of interstellar PAHs. The new feature, in conjunction with other recently discovered spectral structure, suggests that the narrow IR emission features originate in PAH molecules rather than large carbon grains. Larger species are likely to be the source of the broad underlying "plateaus" seen in many of the spectra.

  12. The discovery of a new infrared emission feature at 1905 wavenumbers (5.25 microns) in the spectrum of BD + 30 deg 3639 and its relation to the polycyclic aromatic hydrocarbon model

    NASA Technical Reports Server (NTRS)

    Allamandola, L. J.; Bregman, J. D.; Sandford, S. A.; Tielens, A. G. G. M.; Witteborn, F. C.

    1989-01-01

    A new IR emission feature at 1905/cm (5.25 microns) has been discovered in the spectrum of BD + 30 deg 3639. This feature joins the family of well-known IR emission features at 3040, 2940, 1750, 1610, '1310', 1160, and 890/cm. The origin of this new feature is discussed and it is assigned to an overtone or combination band involving C-H bending modes of polycyclic aromatic hydrocarbons (PAHs). Laboratory work suggests that spectral studies of the 2000-1650/cm region may be very useful in elucidating the molecular structure of interstellar PAHs. The new feature, in conjunction with other recently discovered spectral structures, suggests that the narrow IR emission features originate in PAH molecules rather than large carbon grains.

  13. Airborne spectrophotometry of Eta Carinae from 4.5 to 7.5 microns and a model for source morphology

    NASA Technical Reports Server (NTRS)

    Russell, Ray W.; Lynch, David K.; Hackwell, John A.; Rudy, Richard J.; Rossano, George S.; Castelaz, M. W.

    1987-01-01

    Spectrophotometric observations of Eta Car between 4.5 and 7.5 microns show a featureless thermal-like spectrum with no fine-structure lines or broad emission or absorption features. The color temperature of the spectrum is approximately 375 K. High spatial resolution maps at 3.5, 4.8, and 10 microns obtained from the ground are used to discuss the dust distribution and temperature structure, and to present a model for general source morphology. The upper limit to the brightness of the forbidden Ar II fine-structure emission line at 6.98 microns is less than 7 x 10 to the -16th W/sq cm, which still allows for a significant overabundance of argon and is consistent with the evolved nature of the source.

  14. Autism Spectrum Disorders in Africa: Current Challenges in Identification, Assessment, and Treatment: A Report on the International Child Neurology Association Meeting on ASD in Africa, Ghana, April 3-5, 2014.

    PubMed

    Ruparelia, Kavita; Abubakar, Amina; Badoe, Eben; Bakare, Muideen; Visser, Karren; Chugani, Diane C; Chugani, Harry T; Donald, Kirsten A; Wilmshurst, Jo M; Shih, Andy; Skuse, David; Newton, Charles R

    2016-07-01

    Prevalence of autism spectrum disorders has increased over recent years, however, little is known about the identification and management of autism spectrum disorder in Africa. This report summarizes a workshop on autism spectrum disorder in Africa under the auspices of the International Child Neurology Association and the African Child Neurology Association through guided presentations and working group reports, focusing on identification, diagnosis, management, and community support. A total of 47 delegates participated from 14 African countries. Although there was a huge variability in services across the countries represented, numbers of specialists assessing and managing autism spectrum disorder was small relative to populations served. Strategies were proposed to improve identification, diagnosis, management and support delivery for individuals with autism spectrum disorder across Africa in these culturally diverse, low-resource settings. Emphasis on raising public awareness through community engagement and improving access to information and training in autism spectrum disorder. Special considerations for the cultural, linguistic, and socioeconomic factors within Africa are discussed.

  15. Autism Spectrum Disorders in Africa: Current Challenges in Identification, Assessment, and Treatment: A Report on the International Child Neurology Association Meeting on ASD in Africa, Ghana, April 3-5, 2014.

    PubMed

    Ruparelia, Kavita; Abubakar, Amina; Badoe, Eben; Bakare, Muideen; Visser, Karren; Chugani, Diane C; Chugani, Harry T; Donald, Kirsten A; Wilmshurst, Jo M; Shih, Andy; Skuse, David; Newton, Charles R

    2016-07-01

    Prevalence of autism spectrum disorders has increased over recent years, however, little is known about the identification and management of autism spectrum disorder in Africa. This report summarizes a workshop on autism spectrum disorder in Africa under the auspices of the International Child Neurology Association and the African Child Neurology Association through guided presentations and working group reports, focusing on identification, diagnosis, management, and community support. A total of 47 delegates participated from 14 African countries. Although there was a huge variability in services across the countries represented, numbers of specialists assessing and managing autism spectrum disorder was small relative to populations served. Strategies were proposed to improve identification, diagnosis, management and support delivery for individuals with autism spectrum disorder across Africa in these culturally diverse, low-resource settings. Emphasis on raising public awareness through community engagement and improving access to information and training in autism spectrum disorder. Special considerations for the cultural, linguistic, and socioeconomic factors within Africa are discussed. PMID:26979098

  16. 3 micron spectrophotometry of Comet Halley - Evidence for water ice

    NASA Technical Reports Server (NTRS)

    Bregman, Jesse D.; Tielens, A. G. G. M.; Witteborn, Fred C.; Rank, David M.; Wooden, Diane

    1988-01-01

    Structure has been observed in the 3-3.6 micron preperihelion spectrum of Comet Halley consistent with either an absorption band near 3.1 microns or emission near 3.3 microns. The results suggest that a large fraction of the water molecules lost by the comet are initially ejected in the form of small ice particles rather than in the gas phase.

  17. The 10 micron spectral structure in comets

    NASA Technical Reports Server (NTRS)

    Lynch, David K.; Russell, Ray W.; Campins, Humberto

    1989-01-01

    The 10 micron spectra of comets Halley (1982i), Wilson (1986l), Kohoutek (1973f) and Bradfield (1987s) are presented and compared. The silicate emission profiles of Halley and Bradfield are seen to be remarkably similar in that both contain a sharp break in the spectrum at 11.3 microns. Comet Bradfield does not show the same double peak structure seen in olivine and reported in Comet Halley be Campins and Ryan (1988) and Bregman, et al. (1987). The authors interpret the 11.3 micron signature as being due to olivine-type dust grains with at least some degree of crystallinity. Olivine alone is not enough to reproduce the shape of the 10 micron structure. However, in view of the authors' past success in fitting interstellar dust features with the emissivity profile obtained from amorphous grains produced by laser-vaporizing olivine, this is a very appealing identification. They note that there are significant variations in olivine spectra due to compositional differences, grain size distribution and related grain temperature variations to make the olivine identification tentative. They further tentatively identify the 9.8 micron feature in Halley as being due to either amorphorous olivine or a phyllosilicate (layer lattice). Neither the spectra of Halley, Kohoutek, nor Bradfield exhibited the 12.2 micron feature seen in Comet Wilson, which may prove diagnostic of the composition or thermal history differences between these comets. IR spectra of various mineral samples are discussed in terms of their match to cometary spectra.

  18. 1,3,5-Trinitrobenzene

    Integrated Risk Information System (IRIS)

    1,3,5 - Trinitrobenzene ; CASRN 99 - 35 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health Hazard Assessments for Noncarcino

  19. Micronized grinding apparatus

    SciTech Connect

    Williams, R.M.

    1985-06-11

    Apparatus for grinding coal to micron fineness having a grinding chamber with a grinding surface supported by a circumferential wall in the grinding chamber, a plurality of grinding rolls orbiting in the grinding chamber for grinding the coal, air supply bustle surrounding the grinding chamber, air flow restrictor means opening from the air supply bustle to the grinding chamber to create a back pressure in the air supply bustle for substantially evenly distributing the air supplied to the grinding chamber around the circumference of the grinding chamber, and wherein the restrictor means directs the air flow tangentially relative to the circumferential wall of the grinding chamber so that the coal particles are caught up in a cyclonic movement having a large initial horizontally directed force to maintain a body of coal particles in the orbit of the grinding rolls, which horizontal force gradually diminishes as the vertical force component of the air flow lifts the ground coal particles out of the grinding chamber.

  20. Sub-micron filter

    DOEpatents

    Tepper, Frederick; Kaledin, Leonid

    2009-10-13

    Aluminum hydroxide fibers approximately 2 nanometers in diameter and with surface areas ranging from 200 to 650 m.sup.2/g have been found to be highly electropositive. When dispersed in water they are able to attach to and retain electronegative particles. When combined into a composite filter with other fibers or particles they can filter bacteria and nano size particulates such as viruses and colloidal particles at high flux through the filter. Such filters can be used for purification and sterilization of water, biological, medical and pharmaceutical fluids, and as a collector/concentrator for detection and assay of microbes and viruses. The alumina fibers are also capable of filtering sub-micron inorganic and metallic particles to produce ultra pure water. The fibers are suitable as a substrate for growth of cells. Macromolecules such as proteins may be separated from each other based on their electronegative charges.

  1. Modeling photoacoustic spectral features of micron-sized particles.

    PubMed

    Strohm, Eric M; Gorelikov, Ivan; Matsuura, Naomi; Kolios, Michael C

    2014-10-01

    The photoacoustic signal generated from particles when irradiated by light is determined by attributes of the particle such as the size, speed of sound, morphology and the optical absorption coefficient. Unique features such as periodically varying minima and maxima are observed throughout the photoacoustic signal power spectrum, where the periodicity depends on these physical attributes. The frequency content of the photoacoustic signals can be used to obtain the physical attributes of unknown particles by comparison to analytical solutions of homogeneous symmetric geometric structures, such as spheres. However, analytical solutions do not exist for irregularly shaped particles, inhomogeneous particles or particles near structures. A finite element model (FEM) was used to simulate photoacoustic wave propagation from four different particle configurations: a homogeneous particle suspended in water, a homogeneous particle on a reflecting boundary, an inhomogeneous particle with an absorbing shell and non-absorbing core, and an irregularly shaped particle such as a red blood cell. Biocompatible perfluorocarbon droplets, 3-5 μm in diameter containing optically absorbing nanoparticles were used as the representative ideal particles, as they are spherical, homogeneous, optically translucent, and have known physical properties. The photoacoustic spectrum of micron-sized single droplets in suspension and on a reflecting boundary were measured over the frequency range of 100-500 MHz and compared directly to analytical models and the FEM. Good agreement between the analytical model, FEM and measured values were observed for a droplet in suspension, where the spectral minima agreed to within a 3.3 MHz standard deviation. For a droplet on a reflecting boundary, spectral features were correctly reproduced using the FEM but not the analytical model. The photoacoustic spectra from other common particle configurations such as particle with an absorbing shell and a

  2. Infrared spectroscopy over the 2.9-3.9 microns waveband in biochemistry and astronomy

    NASA Astrophysics Data System (ADS)

    Hoyle, F.; Wickramasinghe, N. C.; Al-Mufti, S.; Olavesen, A. H.; Wickramasinghe, D. T.

    1982-04-01

    Astronomical data for the source GC-IRS 7 are compared with infrared spectra of microorganisms sealed within KBr disks heated in an inert atmosphere up to temperatures of at least 380 C. A remarkably close correspondence is shown between the astronomical spectrum and biology, implying the possibility of a firm spectroscopic identification. Transmittance curves over the wavelength range 2.6-3.9 microns were obtained for E. coli at room temperature and at 350 C and for dehydrated vegetative yeast cells. Thermal stability of the biological materials was found up to about 400 C, and the transmittance curves show a surprising invariance of shape between 3.3 and 3.5 microns for both E. coli and the eukaryote. One spectrum could be explicable on the basis of a single grain model subject to irradiation by hard ultraviolet and X-ray quanta. A search for cosmically relevant organic polymers to produce an even tolerable fit to the data led to negative results.

  3. Airborne spectrophotometry of Comet Halley from 5 to 9 microns

    NASA Technical Reports Server (NTRS)

    Campins, H.; Bregman, J. D.; Witteborn, F. C.; Wooden, D. H.; Rank, D. M.; Cohen, M.; Allamandola, Louis J.; Tielens, Alexander G. G. M.

    1986-01-01

    Spectrophotometry from 5 to 9 microns (resolution = 0.02) of comet Halley was obtained from the Kuiper Airborne Observatory on 1985 Dec. 12.1 and 1986 April 8.6 and 10.5 UT. Two spectral features are apparent in all the observations, one from 5.24 to 5.6 microns, and the silicate emission feature which has an onset between 7 and 8 microns. There is no evidence for the 7.5 microns feature observed by the Vega 1 spacecraft; the large difference between the areal coverage viewed from the spacecraft and the airplane may explain the discrepancy. Color temperatures significantly higher than a blackbody indicate that small particles are abundant in the coma. Significant spatial and temporal variations in the spectrum show trends similar to those observed from the ground.

  4. Micron-gap thermophotovoltaic systems enhanced by nanowires

    NASA Astrophysics Data System (ADS)

    Mirmoosa, Mohammad Sajjad; Simovski, Constantin

    2015-01-01

    We introduce new micron-gap thermophotovoltaic systems enhanced by tungsten nanowires. We theoretically show that these systems allow the frequency-selective super-Planckian spectrum of radiative heat transfer that promises a very efficient generation of electricity. Our system analysis covers practical aspects such as output power per unit area and efficiency of the tap water cooling.

  5. Planetary observations at a wavelength of 355 microns

    SciTech Connect

    De pater, I.; Ulich, B.L.; Kreysa, E.; Chini, R.; Kaman Aerospace Corp., Tucson, AZ; Max-Planck-Institut fuer Radioastronomie, Bonn )

    1989-05-01

    Brightness temperature measurements have been conducted for Jupiter, Saturn, Uranus, and Neptune, as well as the Galilean satellites Europa, Ganymede, and Callisto, and the asteroid Ceres, at 355 microns. The precise shape of the spectra of these bodies can be used to obtain information on their composition and the state of compactness of their surface/subsurface layers. The temperatures obtained for the giant planets agree with both previous measurements and model atmosphere calculations; the present result for Jupiter is noted to be consistent with a model atmosphere spectrum lacking a CH3-ice cloud, or perhaps with one having small (10-micron) particles. 12 refs.

  6. I. Infrared Spectrum of Matrix Isolated Triplet Phenylnitrene. I. Photolysis of Matrix Isolated Quadricyclanone. III. Photolysis of Matrix Isolated 1,3,4,5,6,9-HEXADEUTERIO -7,8-DIAZATETRACYCLO 4.3.0.0(3,5).0(4,9) NON-7-EN-2-ONE

    NASA Astrophysics Data System (ADS)

    Hayes, James Clayton

    Photolysis (lambda = 334 nm) of matrix isolated phenyl azide (1) at 10 K generated triplet phenylnitrene (2) and 1-azacyclohepta-1,2,4,6-tetraene (15) in a ratio of 2:1 even at short (5 sec.) irradiation times. Under the same conditions, the first infrared spectrum of triplet phenylnitrene (2T) was obtained. Photolysis of matrix isolated quadricyclanone (58) at 10 K generated tropone (65) benzene (66) and ketene (67). No oxyallyl (31) was observed from the low temperature matrix isolation experiments. Matrix isolated 1,3,4,5,6,9-hexadeuterio-7,8-diazatetracyclo(4.3.0.0 ^{3,5}.0^ {4,9}) non-7-en-2-one (74) was irradiated in argon and nitrogen matrices to determine if the hexadeuterated photoproduct, 1,2,3,4,5,6-hexadeuteriobicyclo(2.2.1) heptan -7-one (73), would vibrationally cool more rapidly in the nitrogen matrix than in the argon matrix due to increased coupling of similar vibrational modes of 73 and the nitrogen matrix. Similar irradiations in frozen deuterated NMR solvents and analysis by low temperature ^1 H NMR were conducted. Evidence of increased vibrational coupling of similar vibrational modes by IR and NMR analysis was inconclusive.

  7. Titan - 1.5 micron photometry and spectrophotometry and a search for variability

    NASA Technical Reports Server (NTRS)

    Noll, Keith S.; Knacke, Roger F.

    1993-01-01

    The first photometric measurements of Titan in the mid-IR free of possible contamination from long-wavelength filter leaks are reported. A low-resolution spectrum covering the last unobserved gap in Titan's near-IR spectrum from 3.1 to 5.1 micron is shown. A series of photometric measurements is reported that may lay the foundation for long-term searches for variations in the albedos. Low-resolution spectra of Ganymede, Callisto, and Europa are also reported along with marginal detections of Neptune at 4.8 micron and two 4.8 micron observations of Uranus.

  8. Micronized-Coal Burner Facility

    NASA Technical Reports Server (NTRS)

    Calfo, F. D.; Lupton, M. W.

    1986-01-01

    Micronized-coal (coal-in-oil mix) burner facility developed to fulfill need to generate erosion/corrosion data on series of superalloy specimens. In order to successfully operate gas turbine using COM, two primary conditions must be met. First, there must be adequate atomization of COM and second, minimization of coking of burner. Meeting these conditions will be achieved only by clean burning and flame stability.

  9. Electromagnetic Emission at Micron Wavelengths from Active Nerves

    PubMed Central

    Fraser, Allan; Frey, Allan H.

    1968-01-01

    In recent years there has been experimental work and speculation bearing upon the significance in neural functioning of electromagnetic energy in the region of the spectrum between 0.3 and 10 μ. We demonstrate, in this experiment, micron wavelength electromagnetic emission from active live crab nerves as compared to inactive live and dead nerves. Further, the data indicate that the active nerve emission is caused by specific biophysical reactions rather than being simply black-body radiation. PMID:5699805

  10. High Energy 2-micron Laser Developments

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Trieu, Bo C.; Petros, Mulugeta; Bai, Yingxin; Petzar, Paul J.; Koch, Grady J.; Singh, Upendra N.; Kavaya, Michael J.

    2007-01-01

    This viewgraph presentation shows the development of 2-micron solid state lasers. The topics covered include: 1) Overview 2-micron solid state lasers; 2) Modeling and population inversion measurement; 3) Side pump oscillator; and 4) One Joule 2-m Laser.

  11. Extraction, purification, identification and metabolism of 3',5'-cyclic UMP, 3',5'-cyclic IMP and 3',5'-cyclic dTMP from rat tissues.

    PubMed Central

    Newton, R P; Kingston, E E; Hakeem, N A; Salih, S G; Beynon, J H; Moyse, C D

    1986-01-01

    The large-scale extraction and partial purification of endogenous 3',5'-cyclic UMP, 3',5'-cyclic IMP and 3',5'-cyclic dTMP are described. Rat liver, kidney, heart, spleen and lung tissues were subjected to a sequential purification procedure involving freeze-clamping, perchlorate extraction, alumina and Sephadex ion-exchange chromatography and preparative electrophoresis. The samples thus obtained co-chromatographed with authentic cyclic UMP, cyclic IMP and cyclic dTMP on t.l.c. and h.p.l.c. and the u.v. spectra of the extracted samples were identical with those of the standards. Fast atom bombardment of the three cyclic nucleotide standards yielded mass spectra containing a molecular protonated ion in each case; mass-analysed ion kinetic-energy spectrometry ('m.i.k.e.s') of these ions produced a spectrum unique to the parent cyclic nucleotide. The extracted putative cyclic UMP, cyclic IMP and cyclic dTMP each produced a m.i.k.e.s. identical with that obtained with the corresponding cyclic nucleotide standard. Rat liver, heart, kidney, brain, intestine, spleen, testis and lung protein preparations were each found capable of the synthesis of cyclic UMP, cyclic IMP and cyclic dTMP from the corresponding nucleoside triphosphate, of the hydrolysis of these cyclic nucleotides and of their binding, with the exception that cyclic dTMP was not synthesized by the kidney preparation. PMID:3019316

  12. Solid methane on Triton and Pluto - 3- to 4-micron spectrophotometry

    NASA Technical Reports Server (NTRS)

    Spencer, John R.; Buie, Marc W.; Bjoraker, Gordon L.

    1990-01-01

    Methane has been identified in the Pluto/Charon system on the basis of absorption features in the reflectance spectrum at 1.5 and 2.3 microns; attention is presently given to observations of a 3.25 micron-centered deep absorption feature in Triton and Pluto/Charon system reflectance spectra. This absorption may indicate the presence of solid methane, constituting either the dominant surface species or a mixture with a highly transparent substance, such as N2 frost.

  13. Micron-focused ion beamlets

    NASA Astrophysics Data System (ADS)

    Chowdhury, Abhishek; Bhattacharjee, Sudeep

    2010-05-01

    A multiple beam electrode system (MBES) is used to provide focused ion beamlets of elements from a compact microwave plasma. In this study, a honeycomb patterned plasma electrode with micron size apertures for extracting ion beamlets is investigated. The performance of the MBES is evaluated with the help of two widely adopted and commercially available beam simulation tools, AXCEL-INP and SIMION, where the input parameters are obtained from our experiments. A simple theoretical model based upon electrostatic ray optics is employed to compare the results of the simulations. It is found that the results for the beam focal length agree reasonably well. Different geometries are used to optimize the beam spot size and a beam spot ˜5-10 μm is obtained. The multiple ion beamlets will be used to produce microfunctional surfaces on soft matter like polymers. Additionally, the experimental set-up and plans are presented in the light of above applications.

  14. 32 CFR 3.5 - Appropriate use.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTRACTS, GRANTS, OR COOPERATIVE AGREEMENTS FOR PROTOTYPE PROJECTS § 3.5 Appropriate use. In accordance... is participating to a significant extent in the prototype project; or (b) No nontraditional Defense contractor is participating to a significant extent in the prototype project, but at least one of...

  15. 32 CFR 3.5 - Appropriate use.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CONTRACTS, GRANTS, OR COOPERATIVE AGREEMENTS FOR PROTOTYPE PROJECTS § 3.5 Appropriate use. In accordance... is participating to a significant extent in the prototype project; or (b) No nontraditional Defense contractor is participating to a significant extent in the prototype project, but at least one of...

  16. 32 CFR 3.5 - Appropriate use.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... CONTRACTS, GRANTS, OR COOPERATIVE AGREEMENTS FOR PROTOTYPE PROJECTS § 3.5 Appropriate use. In accordance... is participating to a significant extent in the prototype project; or (b) No nontraditional Defense contractor is participating to a significant extent in the prototype project, but at least one of...

  17. 32 CFR 3.5 - Appropriate use.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... CONTRACTS, GRANTS, OR COOPERATIVE AGREEMENTS FOR PROTOTYPE PROJECTS § 3.5 Appropriate use. In accordance... is participating to a significant extent in the prototype project; or (b) No nontraditional Defense contractor is participating to a significant extent in the prototype project, but at least one of...

  18. 32 CFR 3.5 - Appropriate use.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... CONTRACTS, GRANTS, OR COOPERATIVE AGREEMENTS FOR PROTOTYPE PROJECTS § 3.5 Appropriate use. In accordance... is participating to a significant extent in the prototype project; or (b) No nontraditional Defense contractor is participating to a significant extent in the prototype project, but at least one of...

  19. Water Sourcebook. Grades 3-5.

    ERIC Educational Resources Information Center

    Tennessee Valley Authority, Knoxville.

    The goal of this supplemental activity guide for elementary students in grades 3-5 is to develop awareness, knowledge, and skills for sound water use decisions. Materials developed for the program are compatible with existing curriculum standards established by State Boards of Education throughout the United States and teach concepts included in…

  20. Spectroscopy of the 3 micron emission features

    NASA Technical Reports Server (NTRS)

    Geballe, T. R.; Lacy, J. H.; Persson, S. E.; Mcgregor, P. J.; Soifer, B. T.

    1985-01-01

    High-spectral-resolution observations of the 3.3 and 3.4 microns features in the three planetary nebulae NGC 7027, IC 418, and BD +30 deg 3639, in the H II region S106, and in the 'red rectangle' HD 44179 are presented. The profile of the unidentified 3.3 microns emission feature is similar in all five sources. The unidentified feature previously referred to as the 3.4 microns feature actually consists of two components, a low-level emission from 3.35 to 3.60 microns and a narrow emission peak at 3.40 microns. The strength of the latter feature relative to that of the 3.3 microns feature varies by a a factor of three from source to source. The origin and properties of these features may be explained by further development of the small-grain models of Sellgren (1984) and Leger and Puget (1984).

  1. Modeling cloth at micron resolution

    NASA Astrophysics Data System (ADS)

    Bala, Kavita

    2014-02-01

    Fabric is one of the most common materials in our everyday lives, and accurately simulating the appearance of cloth is a critical problem in graphics, design, and virtual prototyping. But modeling and rendering fabric is very challenging because fabrics have a very complex structure, and this structure plays an important role in their visual appearance—cloth is made of fibers that are twisted into yarns which are woven into patterns. Light interacting with this complex structure produce the characteristic visual appearance that humans recognize as silk, cotton, or wool. In this paper we present an end-to-end pipeline to model and render fabrics: we introduce a novel modality to create volume models of fabric at micron resolution using CT technology coupled with photographs; a new technique to synthesize models of user-specified designs from such CT scans; and finally, an efficient algorithm to render these complex volumetric models for practical applications. This pipeline produces the most realistic images of virtual cloth to date, and opens the way to bridging the gap between real and virtual fabric appearance.

  2. Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)

    Integrated Risk Information System (IRIS)

    Hexahydro - 1,3,5 - trinitro - 1,3,5 - triazine ( RDX ) ; CASRN 121 - 82 - 4 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I ( Health

  3. Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)

    Integrated Risk Information System (IRIS)

    Octahydro - 1,3,5,7 - tetranitro - 1,3,5,7 - tetr . . . ( HMX ) ; CASRN 2691 - 41 - 0 Human health assessment information on a chemical substance is included in the IRIS database only after a comprehensive review of toxicity data , as outlined in the IRIS assessment development process . Sections I

  4. Adiabatic pressure dependence of the 2.7 and 1.9 micron water vapor bands

    NASA Technical Reports Server (NTRS)

    Mathai, C. V.; Walls, W. L.; Broersma, S.

    1977-01-01

    An acoustic excitation technique is used to determine the adiabatic pressure derivative of the spectral absorptance of the 2.7 and 1.9 micron water vapor bands, and the 3.5 micron HCl band. The dependence of this derivative on thermodynamic parameters such as temperature, concentration, and pressure is evaluated. A cross-flow water vapor system is used to measure spectral absorptance. Taking F as the ratio of nonrigid to rotor line strengths, it is found that an F factor correction is needed for the 2.7 micron band. The F factor for the 1.9 micron band is also determined. In the wings of each band a wavelength can be found where the concentration dependence is predominant. Farther out in the wings a local maximum occurs for the temperature derivative. It is suggested that the pressure derivative is significant in the core of the band.

  5. High Energy 2-Micron Laser Developments

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Trieu, Bo C.; Petros, Mulugeta; Bai, Yingxin; Petzar, Paul J.; Koch, Grady J.; Singh, Upendra N.; Kavaya, Michael J.

    2007-01-01

    A master oscillator power amplifier, high energy Q-switched 2-micron laser system has been recently demonstrated. The laser and amplifiers are all designed in side-pumped rod configuration, pumped by back-cooled conductive packaged GaAlAs diode laser arrays. This 2-micron laser system provides nearly transform limited beam quality.

  6. One Micron Laser Technology Advancements at GSFC

    NASA Technical Reports Server (NTRS)

    Heaps, William S.

    2010-01-01

    This slide presentation reviews the advancements made in one micron laser technology at Goddard Space Flight Center. It includes information about risk factors that are being addressed by GSFC, and overviews of the various programs that GSFC is currently managing that are using 1 micron laser technology.

  7. Biodegradation of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine

    PubMed Central

    McCormick, N. G.; Cornell, J. H.; Kaplan, A. M.

    1981-01-01

    Biodegradation of the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) occurs under anaerobic conditions, yielding a number of products, including: hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine, hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine, hexahydro-1,3,5-trinitroso-1,3,5-triazine, hydrazine, 1,1-dimethyl-hydrazine, 1,2-dimethylhydrazine, formaldehyde, and methanol. A scheme for the biodegradation of RDX is proposed which proceeds via successive reduction of the nitro groups to a point where destabilization and fragmentation of the ring occurs. The noncyclic degradation products arise via subsequent reduction and rearrangement reactions of the fragments. The scheme suggests the presence of several additional compounds, not yet identified. Several of the products are mutagenic or carcinogenic or both. Anaerobic treatment of RDX wastewaters, which also contain high nitrate levels, would permit the denitrification to occur, with concurrent degradation of RDX ultimately to a mixture of hydrazines and methanol. The feasibility of using an aerobic mode in the further degradation of these products is discussed. PMID:16345884

  8. THUMPER: The 200 Micron Photometer

    NASA Astrophysics Data System (ADS)

    Rinehart, S. A.; Ade, P. A. R.; Griffin, M. J.; Unger, S. J.; Gear, W. K.; Ward-Thompson, D.

    2000-05-01

    THUMPER, the Two-Hundred Micron Photometer, will be a novel new instrument for use on the JCMT and other submillimetre telescopes. Under the best atmospheric conditions at Mauna Kea, a transmission window at 200μ m opens, with atmospheric transmission better than 25% during very dry weather. THUMPER will take advantage of these conditions to take FIR high-resolution (7'') observations with sensitivites comparable to that of instruments previously flown on the Kuiper Airborne Observatory. Further, because of the steep rise in flux towards short wavelengths of thermal sources (which includes most sources of interest), THUMPER will be able to achieve the same SNR as the 450μ m array of SCUBA in a similar amount of time, with similar angular resolution, a capability not provided by any other facility. This instrument will provide powerful new data for the study of many differnt types of astronomical sources, ranging from YSOs and pre-stellar cores to evolved stars to nearby galaxies. One of the primary difficulties in studying such sources is the fact that they have temperature and density distributions which vary across the source. The submillimetre measurements of SCUBA are a powerful tool to study these sources, but these observations are not able to differentiate between temperature and density variations across sources because they do not sample the peak of the Planck function. The FIR observations of ISO and other space-based missions are of value for examination of the global spectral energy distribution, but because of the poor angular resolution of such facilities, cannot be used to separate the effects of temperature and density variations. THUMPER will provide the high-resolution measurements which are needed to differentiate between these effects, opening a valuable new window for FIR astronomy.

  9. Method for sampling sub-micron particles

    DOEpatents

    Gay, Don D.; McMillan, William G.

    1985-01-01

    Apparatus and method steps for collecting sub-micron sized particles include a collection chamber and cryogenic cooling. The cooling is accomplished by coil tubing carrying nitrogen in liquid form, with the liquid nitrogen changing to the gas phase before exiting from the collection chamber in the tubing. Standard filters are used to filter out particles of diameter greater than or equal to 0.3 microns; however the present invention is used to trap particles of less than 0.3 micron in diameter. A blower draws air to said collection chamber through a filter which filters particles with diameters greater than or equal to 0.3 micron. The air is then cryogenically cooled so that moisture and sub-micron sized particles in the air condense into ice on the coil. The coil is then heated so that the ice melts, and the liquid is then drawn off and passed through a Buchner funnel where the liquid is passed through a Nuclepore membrane. A vacuum draws the liquid through the Nuclepore membrane, with the Nuclepore membrane trapping sub-micron sized particles therein. The Nuclepore membrane is then covered on its top and bottom surfaces with sheets of Mylar.RTM. and the assembly is then crushed into a pellet. This effectively traps the sub-micron sized particles for later analysis.

  10. Sub-micron particle sampler apparatus

    DOEpatents

    Gay, Don D.; McMillan, William G.

    1987-01-01

    Apparatus and method steps for collecting sub-micron sized particles include a collection chamber and cryogenic cooling. The cooling is accomplished by coil tubing carrying nitrogen in liquid form, with the liquid nitrogen changing to the gas phase before exiting from the collection chamber in the tubing. Standard filters are used to filter out particles of diameter greater than or equal to 0.3 microns; however the present invention is used to trap particles of less than 0.3 micron in diameter. A blower draws air to said collection chamber through a filter which filters particles with diameters greater than or equal to 0.3 micron. The air is then cryogenically cooled so that moisture and sub-micron sized particles in the air condense into ice on the coil. The coil is then heated so that the ice melts, and the liquid is then drawn off and passed through a Buchner funnel where the liquid is passed through a Nuclepore membrane. A vacuum draws the liquid through the Nuclepore membrane, with the Nuclepore membrane trapping sub-micron sized particles therein. The Nuclepore membrane is then covered on its top and bottom surfaces with sheets of Mylar.RTM. and the assembly is then crushed into a pellet. This effectively traps the sub-micron sized particles for later analysis.

  11. Hexahydro-1,3,5-trinitro-1,3,5-triazine translocation in poplar trees

    SciTech Connect

    Thompson, P.L.; Ramer, L.A.; Schnoor, J.L.

    1999-02-01

    This article evaluates the translocation of the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in hybrid poplar trees (Populus deltoides x nigra, DN34) grown in hydroponic solutions. Mass balances with [U-{sup 14}C]RDX were used to assess RDX translocation. Up to 60% of the RDX uptaken by the tree accumulated in leaf tissues. Analysis of plant extracts by high-performance liquid chromatography equipped with radiochemical detection indicated that RDX was not significantly transformed during exposure periods of up to 7 d. The bioaccumulation of RDX may be an important concern for phytoremediation efforts.

  12. Spatial variations of the 3 micron emission features within UV-excited nebulae - Photochemical evolution of interstellar polycyclic aromatic hydrocarbons

    NASA Technical Reports Server (NTRS)

    Geballe, T. R.; Tielens, A. G. G. M.; Allamandola, L. J.; Moorhouse, A.; Brand, P. W. J. L.

    1989-01-01

    Spectra at 3 microns have been obtained at several positions in the Orion Bar region and in the nebula surrounding HD 44179. Weak emission features at 3.40, 3.46, 3.51, and 3.57 microns are prominent in the Orion Bar region. The 3.40- and 3.51-micron features increase in intensity relative to the dominant 3.29-micron feature. The spectrum obtained in the Red Rectangle region 5 arcsecs north of HD 44179 are similar to those in the Orion Bar, with a weak, broad 3.40-micron feature at the position of HD 44179. The spatial behavior of the weak emission features is explained in terms of hot bands of the CH stretch and overtones, and combination bands of other fundamental vibrations in simple PAHs. Based on the susceptibility of PAHs to destruction by the far UV fields in both regions, PAH sizes are estimated at 20-50 carbon atoms.

  13. Ab initio study of coherent anti-Stokes Raman scattering (CARS) of the 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) explosive

    NASA Astrophysics Data System (ADS)

    Mohammed, Abdelsalam; Ågren, Hans; Thorvaldsen, Andreas J.; Ruud, Kenneth

    2010-01-01

    Coherent anti-Stokes Raman scattering (CARS) of the 1,3,5-trinitro-1,3,5-triazacyclohexane (RDX) C 3H 6N 6O 6 molecule is studied by ab initio methods. The results are compared to available experimental observations and against calculations and experimental observations of the conventional non-resonant Raman spectrum for RDX. It is found that all intense bands in the observed CARS spectrum and all Raman differential cross sections are well reproduced by the calculations. The features of the resonant CARS signal vary strongly from the corresponding Raman signal, and are obtained with a considerably larger cross section, a fact that could further facilitate the use of CARS spectroscopy in applications of stand-off detection of gaseous samples at ultra-low concentrations.

  14. Infrared spectroscopy, imaging, and 10 micron photometry of Giclas 29-38

    NASA Technical Reports Server (NTRS)

    Tokunaga, A. T.; Hodapp, K.-W.; Becklin, E. E.; Cruikshank, D. P.; Rigler, M.; Toomey, D.; Brown, R. H.

    1988-01-01

    An NIR spectrum and several images of Giclas 29-38, a white dwarf suspected to have a brown dwarf in orbit around it, are presented. There is no absorption feature in the spectrum that is deeper than 5 percent in the wavelength range 1.95-2.45 microns, from which it is inferred that there is no feature deeper than 10 percent at 2.4 microns from any brown dwarf companion. The IR spectrum does not yield any strong constraint on whether or not the thermal emission observed from G29-38 comes from a brown dwarf or dust. The 1.6- and 2.2-micron images of G29-38 appear indistinguishable from a point source with an upper limit of 0.4 arcsec for the separation of the white dwarf and the source of the excess IR emission. This corresponds to a projected linear separation of 5.6 AU. A 2sigma limit at 10 microns of 10 mJy constrains possible alternative models for the IR excess by emission from dust grains. While the present results do not show evidence for the suspected brown dwarf companion around G29-38, the presence of such an object cannot be ruled out.

  15. Solid methane on Triton and Pluto - 3- to 4-micron spectrophotometry

    SciTech Connect

    Spencer, J.R.; Buie, M.W.; Bjoraker, G.L. Space Telescope Science Institute, Baltimore, MD NASA, Goddard Space Flight Center, Greenbelt, MD )

    1990-12-01

    Methane has been identified in the Pluto/Charon system on the basis of absorption features in the reflectance spectrum at 1.5 and 2.3 microns; attention is presently given to observations of a 3.25 micron-centered deep absorption feature in Triton and Pluto/Charon system reflectance spectra. This absorption may indicate the presence of solid methane, constituting either the dominant surface species or a mixture with a highly transparent substance, such as N2 frost. 35 refs.

  16. Airborne 20-65 micron spectrophotometry of Comet Halley

    NASA Technical Reports Server (NTRS)

    Glaccum, William; Moseley, S. H.; Campins, Humberto C.; Loewenstein, R. F.

    1988-01-01

    Observations of Comet Halley with a grating spectrometer on board the Kuiper Airborne Observatory on four nights in Dec. 1985 to Apr. 1986 are reported. Low resolution 20 to 65 micrometer spectra of the nucleus with a 40 arcsec FWHM beam was obtained on 17 Dec. 1985, and on 15 and 17 Apr. 1986. On 20 Dec. 1985, only a 20 to 35 micrometer spectrum was obtained. Most of the data have been discussed in a paper where the continuum was dealt with. In that paper, models were fit to the continuum that showed that more micron sized particles of grain similar to amorphous carbon were needed to fit the spectrum than were allowed by the Vega SP-2 mass distribution, or that a fraction of the grains had to be made out of a material whose absorption efficiency fell steeper than lambda sup -1 for lambda greater than 20 micrometers. Spectra was also presented taken at several points on the coma on 15 Apr. which showed that the overall shape to the spectrum is the same in the coma. Tabulated values of the data and calibration curves are available. The spectral features are discussed.

  17. Sub-micron particle sampler apparatus and method for sampling sub-micron particles

    DOEpatents

    Gay, D.D.; McMillan, W.G.

    1984-04-12

    Apparatus and method steps for collecting sub-micron sized particles include a collection chamber and cryogenic cooling. The cooling is accomplished by coil tubing carrying nitrogen in liquid form, with the liquid nitrogen changing to the gas phase before exiting from the collection chamber in the tubing. Standard filters are used to filter out particles of diameter greater than or equal to 0.3 microns; however, the present invention is used to trap particles of less than 0.3 micron in diameter. A blower draws air to said collection chamber through a filter which filters particles with diameters greater than or equal to 0.3 micron. The air is then cryogenically cooled so that moisture and sub-micron sized particles in the air condense into ice on the coil. The coil is then heated so that the ice melts, and the liquid is then drawn off and passed through a Buchner funnel where the liquid is passed through a Nuclepore membrane. A vacuum draws the liquid through the Nuclepore membrane, with the Nuclepore membrane trapping sub-micron sized particles therein. The Nuclepore membrane is then covered on its top and bottom surfaces with sheets of Mylar and the assembly is then crushed into a pellet. This effectively traps the sub-micron sized particles for later analysis. 6 figures.

  18. Application of coherent 10 micron imaging lidar

    SciTech Connect

    Simpson, M.L.; Hutchinson, D.P.; Richards, R.K.; Bennett, C.A.

    1997-04-01

    With the continuing progress in mid-IR array detector technology and high bandwidth fan-outs, i.f. electronics, high speed digitizers, and processing capability, true coherent imaging lidar is becoming a reality. In this paper experimental results are described using a 10 micron coherent imaging lidar.

  19. Efavirenz Dissolution Enhancement I: Co-Micronization

    PubMed Central

    da Costa, Maíra Assis; Seiceira, Rafael Cardoso; Rodrigues, Carlos Rangel; Hoffmeister, Cristiane Rodrigues Drago; Cabral, Lucio Mendes; Rocha, Helvécio Vinícius Antunes

    2012-01-01

    AIDS constitutes one of the most serious infectious diseases, representing a major public health priority. Efavirenz (EFV), one of the most widely used drugs for this pathology, belongs to the Class II of the Biopharmaceutics Classification System for drugs with very poor water solubility. To improve EFV’s dissolution profile, changes can be made to the physical properties of the drug that do not lead to any accompanying molecular modifications. Therefore, the study objective was to develop and characterize systems with efavirenz able to improve its dissolution, which were co-processed with sodium lauryl sulfate (SLS) and polyvinylpyrrolidone (PVP). The technique used was co-micronization. Three different drug:excipient ratios were tested for each of the two carriers. The drug dispersion dissolution results showed significant improvement for all the co-processed samples in comparison to non-processed material and corresponding physical mixtures. The dissolution profiles obtained for dispersion with co-micronized SLS samples proved superior to those of co-micronized PVP, with the proportion (1:0.25) proving the optimal mixture. The improvements may be explained by the hypothesis that formation of a hydrophilic layer on the surface of the micronized drug increases the wettability of the system formed, corroborated by characterization results indicating no loss of crystallinity and an absence of interaction at the molecular level. PMID:24300394

  20. The 11 Micron Emissions of Carbon Stars

    NASA Technical Reports Server (NTRS)

    Goebel, J. H.; Cheeseman, P.; Gerbault, F.

    1995-01-01

    A new classification scheme of the IRAS LRS carbon stars is presented. It comprises the separation of 718 probable carbon stars into 12 distinct self-similar spectral groupings. Continuum temperatures are assigned and range from 470 to 5000 K. Three distinct dust species are identifiable: SiC, alpha:C-H, and MgS. In addition to the narrow 11 + micron emission feature that is commonly attributed to SiC, a broad 11 + micron emission feature, that is correlated with the 8.5 and 7.7 micron features, is found and attributed to alpha:C-H. SiC and alpha:C-H band strengths are found to correlate with the temperature progression among the Classes. We find a spectral sequence of Classes that reflects the carbon star evolutionary sequence of spectral types, or alternatively developmental sequences of grain condensation in carbon-rich circumstellar shells. If decreasing temperature corresponds to increasing evolution, then decreasing temperature corresponds to increasing C/O resulting in increasing amounts of carbon rich dust, namely alpha:C-H. If decreasing the temperature corresponds to a grain condensation sequence, then heterogeneous, or induced nucleation scenarios are supported. SiC grains precede alpha:C-H and form the nuclei for the condensation of the latter material. At still lower temperatures, MgS appears to be quite prevalent. No 11.3 micron PAH features are identified in any of the 718 carbon stars. However, one of the coldest objects, IRAS 15048-5702, and a few others, displays an 11.9 micron emission feature characteristic of laboratory samples of coronene. That feature corresponds to the C-H out of plane deformation mode of aromatic hydrocarbon. This band indicates the presence of unsaturated, sp(sup 3), hydrocarbon bonds that may subsequently evolve into saturated bonds, sp(sup 2), if, and when, the star enters the planetary nebulae phase of stellar evolution. The effusion of hydrogen from the hydrocarbon grain results in the evolution in wavelength of this

  1. The 11 Micron Emissions of Cabon Stars

    NASA Technical Reports Server (NTRS)

    Goebel, J. H.; Cheeseman, P.; Gerbault, F.

    1995-01-01

    A new classification scheme of the IRAS LRS carbon stars is presented. It comprises the separation of 718 probable carbon stars into 12 distinct self-similar spectral groupings. Continuum temperatures are assigned and range from 470 to 5000 K. Three distinct dust species are identifiable: SiC, alpha:C-H, and MgS. In addition to the narrow 11 + micron emission feature that is commonly attributed to SiC, a broad 11 + micron emission feature, that is correlated with the 8.5 and 7.7 micron features, is found and attributed to alpha:C-H. SiC and alpha:C-H band strengths are found to correlate with the temperature progression among the Classes. We find a spectral sequence of Classes that reflects the carbon star evolutionary sequence of spectral types, or alternatively developmental sequences of grain condensation in carbon-rich circumstellar shells. If decreasing temperature corresponds to increasing evolution, then decreasing temperature corresponds to increasing CIO resulting in increasing amounts of carbon rich dust, namely alpha:C-H. If decreasing the temperature corresponds to a grain condensation sequence, then heterogeneous, or induced nucleation scenarios are supported. SiC grains precede alpha:C-H and form the nuclei for the condensation of the latter material. At still lower temperatures, MgS appears to be quite prevalent. No 11.3 micron PAH features are identified in any of the 718 carbon stars. However, one of the coldest objects, IRAS 15048-5702, and a few others, displays an 11.9 micron emission feature characteristic of laboratory samples of coronene. That feature corresponds to the C-H out of plane deformation mode of aromatic hydrocarbon. This band indicates the presence of unsaturated, sp(sup 3), hydrocarbon bonds that may subsequently evolve into saturated bonds, sp(sup 2), if, and when, the star enters the planetary nebulae phase of stellar evolution. The effusion of hydrogen from the hydrocarbon grain results in the evolution in wavelength of this

  2. Water quality criteria for hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).

    PubMed

    Etnier, E L

    1989-04-01

    The occurrence of the munitions compound hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in groundwater surrounding Army ammunition plants may result in contamination of local drinking water supplies. RDX exerts its primary toxic effect in humans on the central nervous system, but also involves gastrointestinal and renal effects. Symptomatic effects following acute exposure include hyperirritability, nausea, vomiting, generalized epileptiform seizures, and prolonged postictal confusion and amnesia. Health effects data were analyzed for RDX, and although no controlled human studies exist concerning the acute or chronic toxic effects of exposure to RDX, sufficient animal toxicity data are available to derive an ambient water quality criterion for the protection of human health. This paper summarizes the available literature on metabolism of RDX and human and animal toxicity. Based on noncarcinogenic mammalian toxicity data, and following the methodologies of the U.S. Environmental Protection Agency, an ambient water quality criterion for the protection of human health of 103 micrograms/liter is proposed for ingestion of drinking water and aquatic foodstuffs. A criterion of 105 micrograms/liter is proposed for ingestion of drinking water alone.

  3. Water quality criteria for hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)

    SciTech Connect

    Etnier, E.L.

    1989-04-01

    The occurrence of the munitions compound hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in groundwater surrounding Army ammunition plants may result in contamination of local drinking water supplies. RDX exerts its primary toxic effect in humans on the central nervous system, but also involves gastrointestinal and renal effects. Symptomatic effects following acute exposure include hyperirritability, nausea, vomiting, generalized epileptiform seizures, and prolonged postictal confusion and amnesia. Health effects data were analyzed for RDX, and although no controlled human studies exist concerning the acute or chronic toxic effects of exposure to RDX, sufficient animal toxicity data are available to derive an ambient water quality criterion for the protection of human health. This paper summarizes the available literature on metabolism of RDX and human and animal toxicity. Based on noncarcinogenic mammalian toxicity data, and following the methodologies of the U.S. Environmental Protection Agency, an ambient water quality criterion for the protection of human health of 103 micrograms/liter is proposed for ingestion of drinking water and aquatic foodstuffs. A criterion of 105 micrograms/liter is proposed for ingestion of drinking water alone.54 references.

  4. Discovering sub-micron ice particles across Dione' surface

    NASA Astrophysics Data System (ADS)

    Scipioni, Francesca; Schenk, Pual; Tosi, Federico; Clark, Roger; Dalle Ore, Cristina; Combe, Jean-Philippe

    2015-11-01

    Water ice is the most abundant component of Saturn’s mid-sized moons. However, these moons show an albedo asymmetry - their leading sides are bright while their trailing side exhibits dark terrains. Such differences arise from two surface alteration processes: (i) the bombardment of charged particles from the interplanetary medium and driven by Saturn’s magnetosphere on the trailing side, and (ii) the impact of E-ring water ice particles on the satellites’ leading side. As a result, the trailing hemisphere appears to be darker than the leading side. This effect is particularly evident on Dione's surface. A consequence of these surface alteration processes is the formation or the implantation of sub-micron sized ice particles.The presence of such particles influences and modifies the surfaces' spectrum because of Rayleigh scattering by the particles. In the near infrared range of the spectrum, the main sub-micron ice grains spectral indicators are: (i) asymmetry and (ii) long ward minimum shift of the absorption band at 2.02 μm (iii) a decrease in the ratio between the band depths at 1.50 and 2.02 μm (iv) a decrease in the height of the spectral peak at 2.6 μm (v) the suppression of the Fresnel reflection peak at 3.1 μm and (vi) the decrease of the reflection peak at 5 μm relative to those at 3.6 μm.We present results from our ongoing work mapping the variation of sub-micron ice grains spectral indicators across Dione' surface using Cassini-VIMS cubes acquired in the IR range (0.8-5.1 μm). To characterize the global variations of spectral indicators across Dione' surface, we divided it into a 1°x1° grid and then averaged the band depths and peak values inside each square cell.We will investigate if there exist a correspondence with water ice abundance variations by producing water ice' absorption band depths at 1.25, 1.52 and 2.02 μm, and with surface morphology by comparing the results with ISS color maps in the ultraviolet, visible and infrared

  5. Laboratory simulation of infrared astrophysical features. [Terrestrial silicate, meteoritic and lunar soil 10-micron spectral comparisons with comets Bennet and Kohoutek

    NASA Technical Reports Server (NTRS)

    Rose, L. A.

    1979-01-01

    Laboratory infrared emission and absorption spectra have been taken of terrestrial silicates, meteorites, and lunar soils in the form of micrometer and submicrometer grains. The emission spectra were taken in a way that imitates telescopic observations. The purpose was to see which materials best simulate the 10-micron astrophysical feature. The emission spectra of dunite, fayalite, and Allende give a good fit to the 10-micron broadband emission feature of comets Bennett and Kohoutek. A study of the effect of grain size on the presence of the 10-micron emission feature of dunite shows that for particles larger than 37 microns no feature is seen. The emission spectrum of the Murray meteorite, a Type 2 carbonaceous chrondrite, is quite similar to the intermediate-resolution spectrum of comet Kohoutek in the 10-micron region. Hydrous silicates or amorphous magnesium silicates in combination with high-temperature condensates, such as olivine or anorthite, would yield spectra that match the intermediate-resolution spectrum of comet Kohoutek in the 10-micron region. Glassy olivine and glassy anorthite in approximately equal proportions would also give a spectrum that is a good fit to the cometary 10-micron feature.

  6. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloroanisole

    SciTech Connect

    Ott, Donald G.; Benziger, Theodore M.

    1991-01-01

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB.

  7. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloroanisole

    SciTech Connect

    Ott, D.G.; Benziger, T.M.

    1991-03-05

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole is described. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB. 8 figures.

  8. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloranisole

    SciTech Connect

    Ott, Donald G.; Benziger, Theodore M.

    1990-01-01

    Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) from 3,5-dichloroanisole. Nitration of 3,5-dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6-trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6-trinitrobenzene. Ammonolysis of this product produced TATB.

  9. Absorption bands in the spectrum of Io

    NASA Technical Reports Server (NTRS)

    Cruikshank, D. P.; Jones, T. J.; Pilcher, C. B.

    1978-01-01

    Near-infrared spectra of Io in the region from 2.8 to 4.2 microns are reported which show distinct absorption features, the most notable at 4.1 microns. Frozen volatiles or atmospheric gases cannot account for these absorptions, nor do they resemble those seen in common silicate rocks. Several candidate substances, most notably nitrate and carbonate salts, show absorption features in this spectral region; the deepest band in the spectrum may be a nitrate absorption. The satellite surface is shown to be anhydrous, as indicated by the absence of the 3-micron bound water band.

  10. Spatial Variation of the 3.29 and 3.40 Micron Emission Bands Within Reflection Nebulae and The Photochemical Evolution of Methylated Polycyclic Aromatic Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Joblin, C.; Tielens, A. G. G. M.; Allamandola, L. J.; Geballe, T. R.

    1996-01-01

    Spectra of 3 microns emission features have been obtained at several positions within the reflection nebulae NGC 1333 SVS3 and NGC 2023. Strong variations of the relative intensities of the 3.29 microns feature and its most prominent satellite band at 3.40 microns are found. It is shown that: (1) the 3.40 microns band is too intense with respect to the 3.29 microns band at certain positions to arise from hot band emission alone, (2) the 3.40 microns band can be reasonably well matched by new laboratory spectra of gas-phase polycyclic aromatic hydrocarbons (PAHs) with alkyl (-CH3) side groups, and (3) the variations in the 3.40 microns to 3.29 microns band intensity ratios are consistent with the photochemical erosion of alkylated PAHs. We conclude that the 3.40 microns emission feature is attributable to -CH3 side groups on PAH molecules. We predict a value of 0.5 for the peak intensity ratio of the 3.40 and 3.29 microns emission bands from free PAHs in the diffuse interstellar medium, which would correspond to a proportion of one methyl group for four peripheral hydrogens. We also compare the 3 microns spectrum of the proto-planetary nebula IRAS 05341 + 0852 with the spectrum of the planetary nebula IRAS 21282 + 5050. We suggest that a photochemical evolution of the initial aliphatic and aromatic hydrocarbon mixture formed in the outflow is responsible for the changes observed in the 3 microns emission spectra of these objects.

  11. Micron Accurate Absolute Ranging System: Range Extension

    NASA Technical Reports Server (NTRS)

    Smalley, Larry L.; Smith, Kely L.

    1999-01-01

    The purpose of this research is to investigate Fresnel diffraction as a means of obtaining absolute distance measurements with micron or greater accuracy. It is believed that such a system would prove useful to the Next Generation Space Telescope (NGST) as a non-intrusive, non-contact measuring system for use with secondary concentrator station-keeping systems. The present research attempts to validate past experiments and develop ways to apply the phenomena of Fresnel diffraction to micron accurate measurement. This report discusses past research on the phenomena, and the basis of the use Fresnel diffraction distance metrology. The apparatus used in the recent investigations, experimental procedures used, preliminary results are discussed in detail. Continued research and equipment requirements on the extension of the effective range of the Fresnel diffraction systems is also described.

  12. Supersonic Flows in Micron-Sized Geometries

    NASA Astrophysics Data System (ADS)

    Bayt, Robert; Breuer, Kenneth

    1998-11-01

    The results of experiments and numerical simulations of flows in micromachined converging-diverging nozzles are presented. The nozzles are fabricated using deep Reactive Ion Etching (DRIE) and are typically 20-30 microns at the throat with expansion ratios ranging from 5 to 20. The flow channels are 300 microns deep, resulting in a 10:1 or better aspect ratio at the throat. Experimental measurements of mass flow and thrust vs. pressure ratio are presented demonstrating the presence of choked and supersonic flow in the micron-scale gemoetries. Mass flow and thrust efficiencies are also presented and compared with results from two-dimensional Navier-Stokes simulations. It is found that, while the efficiencies are reasonably large (much better than one might expect, considering the small dimension of the nozzles), the boundary layers have a considerable effect, particularly on the thrust efficiency of the device, due to the relatively large displacement thickness which reduces the effective expansion ratio. The boundary layers at the top and bottom of the nozzles also affect the performance, particularly at low Reynolds numbers. Additional experimental and numerical results are also discussed.

  13. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene from 3,5-dichloranisole

    SciTech Connect

    Oh, D.G.; Benziger, T.M.

    1990-08-28

    This patent describes the preparation of 1,3,5-triamino-2,4,6- trinitrobenzene (TATB) from 2,5-dichloroanisole. Nitration of 3,5- dichloroanisole under relatively mild conditions gave 3,5-dichloro-2,4,6- trinitroanisole in high yield and purity. Ammonolysis of this latter compound gave the desired TATB. Another route to TATB was through the treatment of the 3,5-dichloro-2,4,6-trinitroanisole with thionyl chloride and dimethylformamide to yield 1,3,5-trichloro-2,4,6- trinitrobenzene. Ammonolysis of this product produced TATB.

  14. Liquid chromatography/electrospray ionization tandem mass spectrometry analysis of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX).

    PubMed

    Pan, Xiaoping; Zhang, Baohong; Tian, Kang; Jones, Lindsey E; Liu, Jun; Anderson, Todd A; Wang, Jia-Sheng; Cobb, George P

    2006-01-01

    A quantitative liquid chromatography/electrospray ionization tandem mass spectrometry (LC/ESI-MS/MS) method was developed for the analysis of the explosive, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). In negative ionization mode, HMX forms an acetate adduct ion [M + CH(3)COO](-), m/z 355, in the presence of a small amount of acetic acid in the mobile phase. The ESI collision-induced dissociation (CID) spectrum of m/z 355 was acquired and the transitions m/z 355 --> 147 and m/z 355 --> 174 were chosen for the determination of HMX in samples. Using this quantification technique, the method detection limit was 1.57 microg/L and good linearity was achieved in the range 5-500 microg/L. This method will help to unambiguously analyze environmentally relevant concentrations of HMX.

  15. The submillimeter spectrum of the cosmic background radiation

    NASA Technical Reports Server (NTRS)

    Matsumoto, T.; Hayakawa, S.; Matsuo, H.; Murakami, H.; Sato, S.

    1988-01-01

    The diffuse brightness of the sky has been measured in six submillimeter passbands, using a rocket-borne, liquid helium-cooled, absolute radiometer. The flux measured at 1160 microns is in good agreement with the average of longer wavelength measurements of the temperature of the cosmic background radiation. The fluxes measured at 709 microns and 481 microns show a rapid decrease toward shorter wavelength, but correspond to significantly higher temperatures. No local source of this excess flux has been identified. The spectrum of the excess significantly constrains cosmological models. Data at 262, 137, and 102 microns are consistent with emission from interstellar dust.

  16. The infrared spectrum of Rhea

    NASA Technical Reports Server (NTRS)

    Clark, R. N.; Owensby, P. D.

    1981-01-01

    The reflectance spectrum of the leading side of the Saturnian satellite Rhea in the 0.65 to 2.5 micron range is reported and used to quantify the amount of water and other materials present on the surface. Data were obtained with 1.5% spectral resolution and 3 to 5% precision by the 3.0-m Infrared Telescope Facility at Mauna Kea Observatory with a continuously scanning circular variable filter spectrometer. Water ice absorptions previously identified at 2.02, 1.65 and 1.55 microns are confirmed, and additional absorptions at 1.25 and probably 1.04 microns are identified. The spectrum of Rhea is noted to be very similar to that of the leading side of Ganymede in the 0.6 to 2.5 micron region and to laboratory spectra of water frost on ice blocks rather than an optically thick frost. Results indicate that the leading side of Rhea is at least 90 wt % water ice, and may be as much as 98 wt %. Of the remaining material, neither clathrates nor minerals is excluded.

  17. 39 CFR 3.5 - Delegation of authority by Board.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 39 Postal Service 1 2014-07-01 2014-07-01 false Delegation of authority by Board. 3.5 Section 3.5 Postal Service UNITED STATES POSTAL SERVICE THE BOARD OF GOVERNORS OF THE U.S. POSTAL SERVICE BOARD OF GOVERNORS (ARTICLE III) § 3.5 Delegation of authority by Board. As authorized by 39 U.S.C. 402, these bylaws delegate to the Postmaster General...

  18. The 11 micron Silicon Carbide Feature in Carbon Star Shells

    NASA Technical Reports Server (NTRS)

    Speck, A. K.; Barlow, M. J.; Skinner, C. J.

    1996-01-01

    Silicon carbide (SiC) is known to form in circumstellar shells around carbon stars. SiC can come in two basic types - hexagonal alpha-SiC or cubic beta-SiC. Laboratory studies have shown that both types of SiC exhibit an emission feature in the 11-11.5 micron region, the size and shape of the feature varying with type, size and shape of the SiC grains. Such a feature can be seen in the spectra of carbon stars. Silicon carbide grains have also been found in meteorites. The aim of the current work is to identity the type(s) of SiC found in circumstellar shells and how they might relate to meteoritic SiC samples. We have used the CGS3 spectrometer at the 3.8 m UKIRT to obtain 7.5-13.5 micron spectra of 31 definite or proposed carbon stars. After flux-calibration, each spectrum was fitted using a chi(exp 2)-minimisation routine equipped with the published laboratory optical constants of six different samples of small SiC particles, together with the ability to fit the underlying continuum using a range of grain emissivity laws. It was found that the majority of observed SiC emission features could only be fitted by alpha-SiC grains. The lack of beta-SiC is surprising, as this is the form most commonly found in meteorites. Included in the sample were four sources, all of which have been proposed to be carbon stars, that appear to show the SiC feature in absorption.

  19. New emission features in the 11-13 micron region and their relationship to polycyclic aromatic hydrocarbons.

    PubMed

    Witteborn, F C; Sandford, S A; Bregman, J D; Allamandola, L J; Cohen, M; Wooden, D H; Graps, A L

    1989-06-01

    If the "11.3 microns" emission feature seen in the spectra of many planetary nebulae, H II regions, and reflection nebulae is due to polycyclic aromatic hydrocarbons (PAHs), then additional features should be present between 11.3 and 13.0 microns (885 and 770 cm-1). Moderate-resolution spectra of NGC 7027, HD 44179, IRAS 21282+5050, and BD + 30 degrees 3639 are presented which show that the "11.3 microns" feature actually peaks at 11.22 microns (891 cm-1). The spectra also show evidence of new emission features near 11.9 and 12.7 microns (840 and 787 cm-1). These are consistent with an origin from PAHs and can be used to constrain the molecular structure of the family of PAHs responsible for the infrared features. The observed asymmetry of the "11.3 microns" band is consistent with the slight anharmonicity expected in the C--H out-of-plane bending mode in PAHs. Laboratory experiments show that the intensity of this mode relative to the higher frequency modes depends on the extent of molecular "clustering." The observed strengths of the "11.3 microns" interstellar bands relative to the higher frequency bands are most consistent with the features originating from free molecular PAHs. The intensity and profile of the underlying broad structure, however, may well arise from PAH clusters and amorphous carbon particles. Analysis of the 11-13 microns (910-770 cm-1) emission suggests that the molecular structures of the most intensity emitting free PAHs vary somewhat between the high-excitation environment in NGC 7027 and the low-excitation but high-flux environment close to HD 44179. Finally, a previously undetected series of regularly spaced features between 10 and 11 microns (1000 and 910 cm-1) in the spectrum of HD 44179 suggests that a simple polyatomic hydride is present in the gas phase in this object. PMID:11542169

  20. Searching for New Physics from 20 microns to a micron and below

    NASA Astrophysics Data System (ADS)

    Geraci, Andrew; Smullin, Sylvia; Weld, David; Kapitulnik, Aharon; Dimopoulos, Savas

    2004-05-01

    Several recent theoretical ideas suggest that new physics related to gravity may appear at short length scales. For example, light moduli or particles in "large" extra dimensions could mediate macroscopic forces of (super)gravitational strength at length scales below a millimeter. At the 20 microns level, I will discuss the Stanford cantilever experiment (J. Chiaverini, S. J. Smullin, A. A. Geraci, D. M. Weld, A. Kapitulnik, Phys.Rev.Lett. 90, 151101 (2003).), including an improvement involving a magnetic analog which allows force calibration and precision alignment to reduce systematics. I will also discuss some experimental challenges at length scales below a few microns including the Casimir/Van der Waals background, and will describe an experimental prospect to search for new (sub)-micron forces using arrays of trapped Bose-Einstein condensed atoms (Savas Dimopoulos and Andrew A. Geraci, Phys. Rev. D 68, 124021 (2003). ).

  1. Novel Tests of Gravity Below Fifty Microns

    NASA Astrophysics Data System (ADS)

    Martinez, Gabriela; Johnson, Jeremy; Guerrero, Ian; Hoyle, C. D.

    2016-03-01

    Due to inconsistencies between General Relativity and the Standard Model, tests of gravity remain at the forefront of experimental physics. At Humboldt State University, undergraduates and faculty are designing an experiment sensitive enough to detect gravitational interactions below the 50 micron scale. The experiment measures the twist of a torsion pendulum as an attractor mass is oscillated nearby in a parallel plate configuration, providing time varying gravitational torque on the pendulum. The size and distance dependence of the torque variation will provide a means to determine any deviation from current models of gravity on untested scales. Supported by NSF Grants 1065697 and 1306783.

  2. Administration of 3,5-diiodothyronine (3,5-T2) causes central hypothyroidism and stimulates thyroid-sensitive tissues.

    PubMed

    Padron, Alvaro Souto; Neto, Ruy Andrade Louzada; Pantaleão, Thiago Urgal; de Souza dos Santos, Maria Carolina; Araujo, Renata Lopes; de Andrade, Bruno Moulin; da Silva Leandro, Monique; de Castro, João Pedro Saar Werneck; Ferreira, Andrea Claudia Freitas; de Carvalho, Denise Pires

    2014-06-01

    In general, 3,5-diiodothyronine (3,5-T2) increases the resting metabolic rate and oxygen consumption, exerting short-term beneficial metabolic effects on rats subjected to a high-fat diet. Our aim was to evaluate the effects of chronic 3,5-T2 administration on the hypothalamus-pituitary-thyroid axis, body mass gain, adipose tissue mass, and body oxygen consumption in Wistar rats from 3 to 6 months of age. The rats were treated daily with 3,5-T2 (25, 50, or 75 μg/100 g body weight, s.c.) for 90 days between the ages of 3 and 6 months. The administration of 3,5-T2 suppressed thyroid function, reducing not only thyroid iodide uptake but also thyroperoxidase, NADPH oxidase 4 (NOX4), and thyroid type 1 iodothyronine deiodinase (D1 (DIO1)) activities and expression levels, whereas the expression of the TSH receptor and dual oxidase (DUOX) were increased. Serum TSH, 3,3',5-triiodothyronine, and thyroxine were reduced in a 3,5-T2 dose-dependent manner, whereas oxygen consumption increased in these animals, indicating the direct action of 3,5-T2 on this physiological variable. Type 2 deiodinase activity increased in both the hypothalamus and the pituitary, and D1 activities in the liver and kidney were also increased in groups treated with 3,5-T2. Moreover, after 3 months of 3,5-T2 administration, body mass and retroperitoneal fat pad mass were significantly reduced, whereas the heart rate and mass were unchanged. Thus, 3,5-T2 acts as a direct stimulator of energy expenditure and reduces body mass gain; however, TSH suppression may develop secondary to 3,5-T2 administration.

  3. 43 CFR 9269.3-5 - Timber management.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Timber management. 9269.3-5 Section 9269.3-5 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT... Timber management. (a) Sales of forest products; general. (b) Non-sale disposals;...

  4. 43 CFR 9269.3-5 - Timber management.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Timber management. 9269.3-5 Section 9269.3-5 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT... Timber management. (a) Sales of forest products; general. (b) Non-sale disposals;...

  5. 43 CFR 9269.3-5 - Timber management.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Timber management. 9269.3-5 Section 9269.3-5 Public Lands: Interior Regulations Relating to Public Lands (Continued) BUREAU OF LAND MANAGEMENT... Timber management. (a) Sales of forest products; general. (b) Non-sale disposals;...

  6. 40 CFR 721.1055 - Benzeneamine, 3,5-difluoro-.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CONTROL ACT SIGNIFICANT NEW USES OF CHEMICAL SUBSTANCES Significant New Uses for Specific Chemical Substances § 721.1055 Benzeneamine, 3,5-difluoro-. (a) Chemical substance and significant new uses subject to reporting. (1) The chemical substance identified as benzeneamine, 3,5-difluoro- (PMN P-97-648; CAS No....

  7. Numerical Modeling of 3.5 {mu }text{m} Dual-Wavelength Pumped Erbium-Doped Mid-Infrared Fiber Lasers

    NASA Astrophysics Data System (ADS)

    Malouf, Andrew; Henderson-Sapir, Ori; Gorjan, Martin; Ottaway, David J.

    2016-11-01

    The performance of mid-infrared erbium doped fiber lasers has dramatically improved in the last few years. In this paper we present a numerical model that provides valuable insight into the dynamics of a dual-wavelength pumped fiber laser that can operate on the 3.5 micron and 2.8 micron bands. This model is a much needed tool for optimizing and understanding the performance of these laser systems. Comparisons between simulation and experimental results for three different systems are presented.

  8. Digital mammography: tradeoffs between 50- and 100-micron pixel size

    NASA Astrophysics Data System (ADS)

    Freedman, Matthew T.; Steller Artz, Dorothy E.; Jafroudi, Hamid; Lo, Shih-Chung B.; Zuurbier, Rebecca A.; Katial, Raj; Hayes, Wendelin S.; Wu, Chris Y.; Lin, Jyh-Shyan; Steinman, Richard M.; Tohme, Walid G.; Mun, Seong K.

    1995-05-01

    Improvements in mammography equipment related to a decrease in pixel size of digital mammography detectors raise questions of the possible effects of these new detectors. Mathematical modeling suggested that the benefits of moving from 100 to 50 micron detectors were slight and might not justify the cost of these new units. Experiments comparing screen film mammography, a storage phosphor 100 micron digital detector, a 50 micron digital breast spot device, 100 micron film digitization and 50 micron film digitization suggests that object conspicuity should be better for digital compared to conventional systems, but that there seemed to be minimal advantage to going from 100 to 50 microns. The 50 micron pixel system appears to provide a slight advantage in object contrast and perhaps in shape definition, but did not allow smaller objects to be detected.

  9. The interstellar 4.62 micron band.

    PubMed

    Pendleton, Y J; Tielens, A G; Tokunaga, A T; Bernstein, M P

    1999-03-01

    We present new 4.5-5.1 micron (2210-1970 cm-1) spectra of embedded protostars, W33 A, AFGL 961 E, AFGL 2136, NGC 7538 IRS 9, and Mon R2 IRS 2, which contain a broad absorption feature located near 4.62 micron (2165 cm-1), commonly referred to in the literature as the "X-C triple bond N" band. The observed peak positions and widths of the interstellar band agree to within 2.5 cm-1 and 5 cm-1, respectively. The strengths of the interstellar 4.62 micrometers band and the ice absorption features in these spectra are not correlated, which suggests a diversity of environmental conditions for the ices we are observing. We explore several possible carriers of the interstellar band and review possible production pathways through far-ultraviolet photolysis (FUV), ion bombardment of interstellar ice analog mixtures, and acid-base reactions. Good fits to the interstellar spectra are obtained with an organic residue produced through ion bombardment of nitrogen-containing ices or with the OCN- ion produced either through acid-base reactions or FUV photolysis of NH3-containing ices.

  10. The 1.2 micron CMOS technology

    NASA Technical Reports Server (NTRS)

    Pina, C. A.

    1985-01-01

    A set of test structures was designed using the Jet Propulsion Laboratory (JPL) test chip assembler and was used to evaluate the first CMOS-bulk foundry runs with feature sizes of 1.2 microns. In addition to the problems associated with the physical scaling of the structures, this geometry provided an additional set of problems, since the design files had to be generated in such a way as to be capable of being processed through p-well, n-well, and twin-well processing lines. This requirement meant that the files containing the geometric design rules as well as the structure design files had to produce process-insensitive designs, a requirement that does not apply to the more mature 3.0-micron CMOS feature size technology. Because of the photolithographic steps required with this feature size, the maximum allowable chip size was 10 x 10 mm, and this chip was divided into 24 project areas, with each area being 1.6 x 1.6 mm in size. The JPL-designed structures occupied 13 out of the 21 allowable project sizes and provided the only test information obtained from these three preliminary runs. The structures were used to successfully evaluate three different manufacturing runs through two separate foundries.

  11. The Two Micron All Sky Survey

    NASA Technical Reports Server (NTRS)

    Kleinmann, S. G.; Lysaght, M. G.; Pughe, W. L.; Schneider, S. E.; Skrutskie, M. F.; Weinberg, M. D.; Price, S. D.; Matthews, K.; Soifer, B. T.; Huchra, J. P.

    1994-01-01

    The Two Micron All Sky Survey (2MASS) will provide a uniform survey of the entire sky at three near-infrared wavebands: J(lambda(sub eff) = 1.25 micrometers), H(lambda(sub eff) = 1.65 micrometers), and K(sub s)(lambda(sub eff) = 2.16 micrometers). A major goal of the survey is to probe large scale structures in the Milky Way and in the Local Universe, exploiting the relatively high transparency of the interstellar medium in the near-infrared, and the high near-infrared luminosities of evolved low- and intermediate-mass stars. A sensitive overview of the near-infrared sky is also an essential next step to maximize the gains achievable with infrared array technology. Our assessment of the astrophysical questions that might be addressed with these new arrays is currently limited by the very bright flux limit of the only preceding large scale near-infrared sky survey, the Two Micron Sky Survey carried out at Caltech in the late 1960's. Near-infrared instruments based on the new array technology have already obtained spectra of objects 1 million times fainter than the limit of the TMSS! This paper summarizes the essential parameters of the 2MASS project and the rationale behind those choices, and gives an overview of results obtained with a prototype camera that has been in operation since May 1992. We conclude with a list of expected data products and a statement of the data release policy.

  12. The Far-Infrared Emission Line and Continuum Spectrum of the Seyfert Galaxy NGC 1068

    NASA Technical Reports Server (NTRS)

    Spinoglio, Luigi; Smith, Howard A.; Gonzalez-Alfonso, Eduardo; Fisher, Jacqueline

    2005-01-01

    We report on the analysis of the first complete far-infrared spectrum (43-197 microns) of the Seyfert 2 galaxy NGC 1068 as observed with the Long Wavelength Spectrometer (LWS) onboard the Infrared Space Observatory (ISO). In addition to the 7 expected ionic fine structure emission lines, the OH rotational lines at 79, 119 and 163 microns were all detected in emission, which is unique among galaxies with full LWS spectra, where the 119 micron line, where detected, is always in absorption. The observed line intensities were modelled together with IS0 Short Wavelength Spectrometer (SWS) and optical and ultraviolet line intensities from the literature, considering two independent emission components: the AGN component and the starburst component in the circumnuclear ring of approximately 3kpc in size. Using the UV to mid-IR emission line spectrum to constrain the nuclear ionizing continuum, we have confirmed previous results: a canonical power-law ionizing spectrum is a poorer fit than one with a deep absorption trough, while the presence of a big blue bump is ruled out. Based on the instantaneous starburst age of 5 Myr constrained by the Br gamma equivalent width in the starburst ring, and starburst synthesis models of the mid- and far-infrared fine-structure line emission, a low ionization parameter (U=10(exp -3.5)) and low densities (n=100 cm (exp -3)) are derived. Combining the AGN and starburst components, we succeed in modeling the overall UV to far-IR atomic spectrum of SGC 1068, reproducing the line fluxes to within a factor 2.0 on average with a standard deviation of 1.4. The OH 119 micron emission indicates that the line is collisionally excited, and arises in a warm and dense region. The OH emission has been modeled using spherically symmetric, non-local, non-LTE radiative transfer models. The models indicate that the bulk of the emission arises from the nuclear region, although some extended contribution from the starburst is not ruled out. The OH abundance

  13. Identification of ovine ruminal microbes capable of biotransforming hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Bioremediation is of great interest in the detoxification of soil contaminated with residues from explosives such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Although there are numerous forms of in situ and ex situ bioremediation, ruminants would provide the option of an in situ bioreactor tha...

  14. IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) (Interagency Science Consultation Draft)

    EPA Science Inventory

    On March 10, 2016, the public comment draft Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine and the draft charge to external peer reviewers were released for public review and comment. The Toxicological Review and charge were reviewed internally by EPA and by othe...

  15. IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) (Public Comment Draft)

    EPA Science Inventory

    EPA is developing an Integrated Risk Information System (IRIS) assessment of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and has released the draft assessment for public comment. When final, the assessment will appear on the IRIS database.

  16. IRIS Toxicological Review of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (Rdx) (External Review Draft)

    EPA Science Inventory

    The IRIS Toxicological Review of Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was released for external peer review in September 2016. The EPA’s Science Advisory Board’s (SAB) Chemical Assessment Advisory Committee (CAAC) will conduct a peer review of the scientific basis suppor...

  17. Spitzer IRS (8-30 micron) Spectra of Basaltic Asteroids 1459 Magnya and 956 Elisa: Mineralogy and Thermal Properties

    NASA Technical Reports Server (NTRS)

    Lim, Lucy F.; Emery, J. P.; Moskovitz, N. A.

    2009-01-01

    We report preliminary results from Spitzer IRS (Infrared Spectrograph) spectroscopy of 956 Elisa, 1459 Magnya, and other small basaltic asteroids with the Spitzer IRS. Program targets include members of the dynamical family of the unique large differentiated asteroid 4 Vesta ("Vestoids"), several outer-main-belt basaltic asteroids whose orbits exclude them from originating on 4 Vesta, and the basaltic near-Earth asteroid 4055 Magellan. The preliminary thermal model (STM) fit to the 5--35 micron spectrum of 956 Elisa gives a radius of 5.4 +/- 0.3 km and a subsolar- point temperature of 282.2 +/- 0.5 K. This temperature corresponds to eta approximately equals 1.06 +/- 0.02, which is substantially higher than the eta approximately equals 0.756 characteristic of large main-belt asteroids. Unlike 4 Vesta and other large asteroids, therefore, 956 Elisa has significant thermal inertia in its surface layer. The wavelength of the Christiansen feature (emissivity maximum near 9 micron), the positions and shapes of the narrow maxima (10 micron, 11 micron) within the broad 9--14 micron silicate band, and the 19--20 micron minimum are consistent with features found in the laboratory spectra of diogenites and of low-Ca pyroxenes of similar composition (Wo<5, En50-En75).

  18. New MBE buffer for micron- and quarter-micron-gateGaAs MESFETs

    NASA Technical Reports Server (NTRS)

    1988-01-01

    A new buffer layer has been developed that eliminates backgating in GaAs MESFETs and substantially reduces short-channel effects in GaAs MESFETs with 0.27-micron-long gates. The new buffer is grown by molecular beam epitaxy (MBE) at a substrate temperature of 200 C using Ga and As sub 4 beam fluxes. The buffer is crystalline, highly resistive, optically inactive, and can be overgrown with high quality GaAs. GaAs MESFETs with a gate length of 0.27 microns that incorporate the new buffer show improved dc and RF properties in comparison with a similar MESFET with a thin undoped GaAs buffer. To demonstrate the backgating performance improvement afforded by the new buffer, MESFETs were fabricated using a number of different buffer layers and structures. A schematic cross section of the MESFET structure used in this study is shown. The measured gate length, gate width, and source-drain spacing of this device are 2,98, and 5.5 microns, respectively. An ohmic contact, isolated from the MESFET by mesa etching, served as the sidegate. The MESFETs were fabricated in MBE n-GaAs layers grown on the new buffer and also in MBE n-GaAs layers grown on buffer layers of undoped GaAs, AlGaAs, and GaAs/AlGaAs superlattices. All the buffer layers were grown by MBE and are 2 microns thick. The active layer is doped to approximately 2 x 10 to the 17th/cu cm with silicon and is 0.3 microns thick.

  19. Spatial variations of the 3 micron emission features within nebulae

    NASA Technical Reports Server (NTRS)

    Moorhouse, Alan; Geballe, T. R.; Allamandola, Louis J.

    1989-01-01

    The 3 micron spectra is presented for the Orion bar region and the Red Rectangle. In both objects spectra were obtained at more than one location, corresponding to different distances from the excitation source. The well known 3.3 and 3.4 micron emission bands are seen in both objects as well as the recently discovered features at 3.46, 3.51, and 3.57 microns in the Orion bar spectra. The spectra show that the relative strengths of the 3 micron emission features vary within the Orion bar. As distance from the exciting star increases, the 3.4 and 3.51 micron features increase, and the 3.46 micron feature decreases in strength, relative to the strong 3.3 micron feature. These are two possible interpretations which are postulated, each of which involves the breaking of bonds by UV radiation, which removes the modes responsible for the 3.4 micron emission near the star. The two possible bond ruptures are the CH bond in small polycyclic aromatic hydrocarbons (PAHs), or the bond to an aliphatic subgroup. It has to be pointed out that neither interpretation appears entirely satisfactory. The vibrational overtone interpretation cannot explain the presence or behavior of the 3.46 micron feature, whereas the laboratory spectra of aliphatic sidegroups contain many more features in the 3 micron region than are observed in the astronomical sources.

  20. Phosphatidylinositol 3,5-bisphosphate: metabolism and cellular functions.

    PubMed

    Michell, Robert H; Heath, Victoria L; Lemmon, Mark A; Dove, Stephen K

    2006-01-01

    Polyphosphoinositides (PPIn) are low-abundance membrane phospholipids that each bind to a distinctive set of effector proteins and, thereby, regulate a characteristic suite of cellular processes. Major functions of phosphatidylinositol 3,5-bisphosphate [PtdIns(3,5)P(2)] are in membrane and protein trafficking, and in pH control in the endosome-lysosome axis. Recently identified PtdIns(3,5)P(2) effectors include a family of novel beta-propeller proteins, for which we propose the name PROPPINs [for beta-propeller(s) that binds PPIn], and possibly proteins of the epsin and CHMP (charged multi-vesicular body proteins) families. All eukaryotes, with the exception of some pathogenic protists and microsporidians, possess proteins needed for the formation, metabolism and functions of PtdIns(3,5)P(2). The importance of PtdIns(3,5)P(2) for normal cell function is underscored by recent evidence for its involvement in mammalian cell responses to insulin and for PtdIns(3,5)P(2) dysfunction in the human genetic conditions X-linked myotubular myopathy, Type-4B Charcot-Marie-Tooth disease and fleck corneal dystrophy.

  1. On Io's 2.788-micron band: Origin by SO2 or H2O?

    NASA Astrophysics Data System (ADS)

    Nash, D. B.

    1994-02-01

    Laboratory reflectance spectra of SO2 frost and ice and thin H2O frost show that the recently reported band at 2.788 microns in Io's disk-integrated spectrum can be qualitatively explained by the presence of solid SO2 on Io's surface. However, the reported width of the Io band is too great to be explained by SO2 frost or ice alone. Lab spectra presented here, and other data cited here, show clearly that solid SO2 has a strong band at 2.789 microns, and that Io should have such a band. These results do not support the claim of Bregman et al. that H2O is the primary cause of the Io band.

  2. Zellweger Spectrum

    MedlinePlus

    ... the Zellweger spectrum result from defects in the assembly of a cellular structure called the peroxisome, and ... Zellweger spectrum are caused by defects in the assembly of the peroxisome. There are at least 12 ...

  3. Degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Stenotrophomonas maltophilia PB1.

    PubMed Central

    Binks, P R; Nicklin, S; Bruce, N C

    1995-01-01

    A mixed microbial culture capable of metabolizing the explosive RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) was obtained from soil enrichments under aerobic and nitrogen-limiting conditions. A bacterium, Stenotrophomonas maltophilia PB1, isolated from the culture used RDX as a sole source of nitrogen for growth. Three moles of nitrogen was used per mole of RDX, yielding a metabolite identified by mass spectroscopy and 1H nuclear magnetic resonance analysis as methylene-N-(hydroxymethyl)-hydroxylamine-N'-(hydroxymethyl)nitroamin e. The bacterium also used s-triazine as a sole source of nitrogen but not the structurally similar compounds octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, cyanuric acid, and melamine. An inducible RDX-degrading activity was present in crude cell extracts. PMID:7747953

  4. Poly[(μ-3,5-dinitro-benzoato)(μ-3,5-dinitro-benzoic acid)rubidium].

    PubMed

    Miao, Yanqing; Fan, Tao

    2011-08-01

    The asymmetric unit of the title compound, [Rb(C(7)H(3)N(2)O(6))(C(7)H(4)N(2)O(6))](n), comprises an Rb(+) cation, a 3,5-dinitro-benzoate anion and a 3,5-dinitro-benzoic acid ligand. The Rb(+) cation is nine-coordinated by O atoms from four 3,5-dinitro-benzoate anions and three neutral 3,5-dinitro-benzoic acid ligands. The metal atom is firstly linked by four bridging carboxyl groups, forming a binuclear motif, which is further linked by the nitro groups into a two-dimensional framework along the [110] direction. A short O-H⋯O hydrogen bond between two adjacent carboxy/carboxylate groups occurs. PMID:22090832

  5. Near 16 micron CO.sub.2 laser system

    DOEpatents

    Krupke, William F.

    1977-01-01

    Method and apparatus for inducing laser action in CO.sub.2 at a wavelength of 16 microns involving the transition between the 02.sup.0 0 and 01.sup.1 0 states. The population inversion between these two states is achieved by pumping to the 00.sup.0 1 level, suppressing the usual 10.6 micron transition to the 10.sup.0 0 level and encouraging the 9.6 micron transition, thereby populating the 02.sup.0 0 level, as the principal prerequisite for 16 micron laser action between the 02.sup.0 0 and 01.sup.1 0 levels.

  6. Hexahydro-1,3,5-trinitro-1,3,5-triazine mineralization by zerovalent iron and mixed anaerobic cultures.

    PubMed

    Oh, B T; Just, C L; Alvarez, P J

    2001-11-01

    Soil microcosms were used to evaluate the potential benefits of an integrated microbial-Fe0 system to treat groundwater contamination by RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine). Microcosms amended with both Fe0 filings and municipal anaerobic sludge mineralized RDX faster and to a greater extent than separate treatments, with up to 51% 14CO2 recovery after 77 d. The nitroso byproducts 1,3-dinitro-5-nitroso-1,3,5-triazacyclohexane (MNX), 1,3-dinitroso-5-nitro-1,3,5-triazacyclohexane (DNX), and 1,3,5-trinitroso-1,3,5-triazacyclohexane (TNX) were detected in all microcosms, although these compounds never accumulated above 5% of the added RDX on a molar basis. A soluble intermediate that was tentatively identified as methylenedinitramine [(O2NNH)2CH2] was relatively persistent, although it accumulated to a much lower extent in combined-treatment reactors than in sets with Fe0 or sludge alone. Some of the radiolabel was bound to soil and Fe0 and could not be extracted with CH3CN. This fraction, which was recovered by combustion with a biological oxidizer, was also found at lower concentrations in combined-treatment reactors. This work suggests that permeable reactive Fe0 barriers might be an effective approach to intercept and degrade RDX plumes and that treatment efficiency might be enhanced by biogeochemical interactions through bioaugmentation.

  7. Roles of the 2 microns gene products in stable maintenance of the 2 microns plasmid of Saccharomyces cerevisiae.

    PubMed Central

    Reynolds, A E; Murray, A W; Szostak, J W

    1987-01-01

    We have examined the replication and segregation of the Saccharomyces cerevisiae 2 microns circle. The amplification of the plasmid at low copy numbers requires site-specific recombination between the 2 microns inverted repeat sequences catalyzed by the plasmid-encoded FLP gene. No other 2 microns gene products are required. The overexpression of FLP in a strain carrying endogenous 2 microns leads to uncontrolled plasmid replication, longer cell cycles, and cell death. Two different assays show that the level of Flp activity decreases with increasing 2 microns copy number. This regulation requires the products of the REP1 and REP2 genes. These gene products also act together to ensure that 2 microns molecules are randomly segregated between mother and daughter cells at cell division. Images PMID:3316982

  8. NMR Microscopy - Micron-Level Resolution.

    NASA Astrophysics Data System (ADS)

    Kwok, Wing-Chi Edmund

    1990-01-01

    Nuclear Magnetic Resonance Imaging (MRI) has been developed into a powerful and widely used diagnostic tool since the invention of techniques using linear magnetic field gradients in 1973. The variety of imaging contrasts obtainable in MRI, such as spin density, relaxation times and flow rate, gives MRI a significant advantage over other imaging techniques. For common diagnostic applications, image resolutions have been in the order of millimeters with slice thicknesses in centimeters. For many research applications, however, resolutions in the order of tens of microns or smaller are needed. NMR Imaging in these high resolution disciplines is known as NMR microscopy. Compared with conventional microscopy, NMR microscopy has the advantage of being non-invasive and non-destructive. The major obstacles of NMR microscopy are low signal-to-noise ratio and effects due to spin diffusion. To overcome these difficulties, more sensitive RF probes and very high magnetic field gradients have to be used. The most effective way to increase sensitivity is to build smaller probes. Microscope probes of different designs have been built and evaluated. Magnetic field gradient coils that can produce linear field gradients up to 450 Gauss/cm were also assembled. In addition, since microscope probes often employ remote capacitors for RF tuning, the associated signal loss in the transmission line was studied. Imaging experiments have been carried out in a 2.1 Tesla small bore superconducting magnet using the typical two-dimensional spin warp imaging technique. Images have been acquired for both biological and non-biological samples. The highest resolution was obtained in an image of a nerve bundle from the spinal cord of a racoon and has an in-plane resolution of 4 microns. These experiments have demonstrated the potential application of NMR microscopy to pathological research, nervous system study and non -destructive testings of materials. One way to further improve NMR microscopy is

  9. 3.5 billion years of glass bioalteration: Volcanic rocks as a basis for microbial life?

    SciTech Connect

    Staudigel, H.; Furnes, H.; McLoughlin, N.; Banerjee, N.R.; Connell, L.B.; Templeton, A.

    2009-04-07

    Alteration textures in volcanic glass from the seafloor fall into two classes, one suggestive of abiotic/diffusive hydration and chemical exchange, and another likely to be caused by microbial, cavity-forming, congruent dissolution. Glass bioalteration is common in submarine lavas throughout the world's ocean, dominant in the upper 300 m of the oceanic crust, and found in all well-preserved ophiolites and greenstone belts dating back to 3.5 Ga. It may yield a significant fraction of the global biomass and geochemical fluxes and is relevant to the development of the earliest life on Earth. We present a critical review concerning these glass bioalteration textures and present new data on their microchemical environment. We explore arguments for their biogenicity and further develop the prevalent model for their formation by relating corrosion morphology to the mechanism of microbial dissolution. Biological alteration produces conspicuous micron-scale granular and tubular textures. Granular glass alteration is well explained by colonizing microbes that selectively dissolve the glass in their contact area, forming a sponge-like interconnected network of micron-sized cavities along glass surfaces. Tubular alteration meanwhile, is more likely to be caused by filamentous cell extensions in a process similar to fungal tunneling of soil feldspars and marine carbonates. While we see clear functional similarities to fungal dissolution behavior, we do not know whether fungal or prokaryotic organisms are involved. However, this functional constraint may eventually help to identify potential microbes responsible for these features, potentially including eukaryotic or prokaryotic organisms. Yet, we caution that these organisms may be difficult to identify and to study, because they are likely to be sparsely distributed, slow growing, and difficult to cultivate.

  10. Deformation Behavior of Sub-micron and Micron Sized Alumina Particles in Compression.

    SciTech Connect

    Sarobol, Pylin; Chandross, Michael E.; Carroll, Jay; Mook, William; Boyce, Brad; Kotula, Paul Gabriel; McKenzie, Bonnie Beth; Bufford, Daniel Charles; Hall, Aaron Christopher.

    2014-09-01

    The ability to integrate ceramics with other materials has been limited due to high temperature (>800degC) ceramic processing. Recently, researchers demonstrated a novel process , aerosol deposition (AD), to fabricate ceramic films at room temperature (RT). In this process, sub - micro n sized ceramic particles are accelerated by pressurized gas, impacted on the substrate, plastically deformed, and form a dense film under vacuum. This AD process eliminates high temperature processing thereby enabling new coatings and device integration, in which ceramics can be deposited on metals, plastics, and glass. However, k nowledge in fundamental mechanisms for ceramic particle s to deform and form a dense ceramic film is still needed and is essential in advancing this novel RT technology. In this wo rk, a combination of experimentation and atomistic simulation was used to determine the deformation behavior of sub - micron sized ceramic particle s ; this is the first fundamental step needed to explain coating formation in the AD process . High purity, singl e crystal, alpha alumina particles with nominal size s of 0.3 um and 3.0 um were examined. Particle characterization, using transmission electron microscopy (TEM ), showed that the 0.3 u m particles were relatively defect - free single crystals whereas 3.0 u m p articles were highly defective single crystals or particles contained low angle grain boundaries. Sub - micron sized Al 2 O 3 particles exhibited ductile failure in compression. In situ compression experiments showed 0.3um particles deformed plastically, fractured, and became polycrystalline. Moreover, dislocation activit y was observed within the se particles during compression . These sub - micron sized Al 2 O 3 particles exhibited large accum ulated strain (2 - 3 times those of micron - sized particles) before first fracture. I n agreement with the findings from experimentation , a tomistic simulation s of nano - Al 2 O 3 particles showed dislocation slip and

  11. Radioimmunoassay for 3,5-diiodothyronine and evidence for dependence on conversion from 3,5,3'-triiodothyronine

    SciTech Connect

    Pangaro, L.; Burman, K.D.; Wartofsky, L.; Cahnmann, H.J.; Smallridge, R.C.; O'Brian, J.T.; Wright, F.D.; Latham, K.

    1980-06-01

    The present report describes a RIA for 3,5-diiodothyronine (3,5T/sub 2/) which uses inner ring-labeled 3,5-(/sup 125/I)T/sub 2/ as the ligand and has a lower limit of detectability of 0.5 ng/dl. Cross-reaction was 0.14% with T/sub 3/, less than 0.001% with T/sub 4/, 1.2% with 3,3',5-triiodothyroacetic acid, and 6.1% with 3,5-diiodothyroacetic acid. No cross-reaction was detectable for iodothyronines within their physiological ranges. Intraassay variation ranged from 2.2 to 7.8%, and interassay variation ranged from 12.7 to 14%. The mean (+-SE) serum 3.5T/sub 2/ concentration in 70 normal subjects was 4.3 +- 0.2 ng/dl. The mean (+-SE) 3.5T/sub 2/ in 14 hyperthyroid patients was increased to 18.4 +- 2.3 ng/dl (P < 0.001), and all but 1 patient had an elevated level. In 10 hypothyroid patients the mean (+-SE) 3,5T/sub 2/ level was decreased to 1.4 +- 0.3 ng/dl (P < 0.001). In 4 patients, levels overlapped with the normal range. In 4 hypothyroid subjects treated with L-T/sub 1/, 3,5T/sub 2/ levels were normal, suggesting that the majority of 3,5T/sub 2/ originates from extrathyroidal conversion from T/sub 3/. Studies in fasting obese subjects demonstrated that serum 3,5T/sub 2/ (mean +- SE) levels fell from 3.4 +- 0.3 to 2.5 +- 0.7 ng/dl during fasting. This fall was significant (P < 0.001) and in parallel with the fall in T/sub 3/ levels of 182 +- 20 to 126 +- 12 ng/dl. In fasting subjects given 100 ..mu..g oral L-T/sub 3//day T/sub 3/ levels rose from 138 +- 11 to 362 +- 26 ng/dl. 3,5T/sub 2/ levels (corrected for cross-reaction and for contamination of oral T/sub 3/ with 3,5T/sub 2/) rose from 2.2 +- 0.7 to 6.4 +- 1.0 ng/dl. In fasting subjects given 25 ..mu..g oral L-T/sub 3//day, T/sub 3/ levels fell from 165 +- 5.1 to 139 +- 6.9 ng/dl. Corrected 3,5T/sub 2/ levels changed from 3.7 +- 0.4 to 2.5 +- 0.3 ng/dl. Neither change were significant.

  12. Spectra of Uranus and Neptune at 8-14 and 17-23 microns

    SciTech Connect

    Orton, G.S.; Aitken, D.K.; Smith, C.; Roche, P.F.; Caldwell, J.

    1987-04-01

    The 3-m NASA Infrared Telescope Facility was used to observe the disks of Uranus and Neptune between May 30 and June 1, 1985 in the 7-14 and 17-23 micron spectral regions. Maximum stratospheric mixing ratios of 9 x 10 to the -9th for C/sub 2/H/sub 2/, and of 2 x 10 to the -8th for C/sub 2/H/sub 6/, are found for Uranus, and the spectrum is otherwise smooth, consistent with the opacity provided by H/sub 2/ collision-induced absorption and spectrally continuous stratospheric emission. Strong emission features of CH/sub 4/ and C/sub 2/H/sub 6/ are found in the short-wavelength spectrum of Neptune, and the spectrum near 13.5 microns is consistent with C/sub 2/H/sub 2/ emission in local saturation equilibrium with a maximum mixing ratio of 9 x 10 to the -7th. 27 references.

  13. 3,5-Dichlorophenol Removal From Wastewater Using Alternative Adsorbents

    NASA Astrophysics Data System (ADS)

    Kobetičová, Hana; Lipovský, Marek; Wachter, Igor; Soldán, Maroš

    2015-06-01

    The main objective of this paper is to evaluate the efficiency of 3,5-dichlorophenol removal from wastewater by using alternative low cost adsorbents. Waste from the production and processing of metals (black nickel mud, red mud) and a biosorbent (Lemna minor) were used for this research. Initial concentration of the contaminant was 4 mmol L-1, the contact time of sorbent and waste water was 0 - 48 hrs and the temperature during experiment was 25 ± 0.2 °C. The results show that the highest removal efficiency of 3,5 - dichlorophenol (58.18 %) was reached by the red mud in 48 hours.

  14. Infrared (2.08-14 micron) spectra of powered stony meteorites

    NASA Technical Reports Server (NTRS)

    Salisbury, J. W.; Daria, D. M.; Jarosewich, E.

    1991-01-01

    Infrared biconical reflectance spectra of 60 powdered meteorite samples, representing 50 different stony meteorites, were measured as analogues of asteroidal regolith. Representative samples were measured in directional hemispherical reflectance to assure that Kirchhoff's Law can be used to predict relative emissivity from the reflectance spectra. These spectral data confirm that the O-H fundamental absorption band near 2.9 microns is an extremely sensitive indicator of incipient alteration, which often has taken place in powdered meteorite samples exposed only to water vapor in the air. Such non-carbonaceous samples typically contain less than 1 percent water by weight. Likewise, the C-H fundamental absorption bands near 3.4 and 3.5 microns are equally sensitive indicators of contamination with volatile hydrocarbons, which can also be absorbed from the air. The heavy, macromolecular hydrocarbons native to chondrites do not display such heavy bands, making detection of these bands in remote sensing of asteroids unlikely. Despite the spectral artifacts introduced by alteration and hydrocarbon contamination, powdered stony meteorites display a wide variety of real spectral features that can be used for their identification, including residual reststrahlen bands, absorption bands, and the Christiansen feature. Researchers found that the wavelengths of the peaks or troughs of each of these spectral features can be used independently to infer meteorite composition, but the best results are obtained when the entire spectral curve is used, or at least the portion of it encompassed by the 8 to 14 micron atmospheric window, in a digital search library.

  15. A high-resolution atlas of the infrared spectrum of the Sun and the Earth atmosphere from space: A compilation of ATMOS spectra of the region from 650 to 4800 cm (2.3 to 16 micron). Volume 1: The Sun

    NASA Technical Reports Server (NTRS)

    Farmer, Crofton B.; Norton, Robert H.

    1989-01-01

    During the period April 29 through May 2, 1985, the Atmospheric Trace Molecular Spectroscopy experiment was operated as part of the Spacelab-3 payload of the shuttle Challenger. The instrument, a modified Michelson Interferometer covering the frequency range from 600 to 5000/cm, at a spectral resolution of 0.01/cm, recorded infrared spectra of the Sun and of the Earth's atmosphere at times close to entry into and exit from occultation by the Earth's limb as seen from the shuttle orbit of 360 km. Spectra were obtained that are free from absorptions due to constituents of the atmosphere (i.e., solar pure spectra), as well as spectra of the atmosphere itself, covering line-of-sight tangent altitudes that span the range from the lower thermosphere to the bottom of the troposphere. This atlas, believed to be the first record of observations of the continuous high resolution infrared spectrum of the Sun and the Earth's atmosphere from space, provides a compilation of these spectra arranged in a hardcopy format suitable for quick-look reference purposes; the data are also available in digital form.

  16. Improved properties of micronized genetically modified flax fibers.

    PubMed

    Dymińska, Lucyna; Szatkowski, Michał; Wróbel-Kwiatkowska, Magdalena; Zuk, Magdalena; Kurzawa, Adam; Syska, Wojciech; Gągor, Anna; Zawadzki, Mirosław; Ptak, Maciej; Mączka, Mirosław; Hanuza, Jerzy; Szopa, Jan

    2012-12-15

    The aim of this study was to investigate the effect of micronization on the compound content, crystalline structure and physicochemical properties of fiber from genetically modified (GM) flax. The GM flax was transformed with three bacterial (Ralstonia eutropha) genes coding for enzymes of polyhydroxybutyrate (PHB) synthesis and under the control of the vascular bundle promoter. The modification resulted in fibers containing the 3-hydroxybutyrate polymer bound to cellulose via hydrogen and ester bonds and antioxidant compounds (phenolic acids, vanillin, vitexin, etc.). The fibers appeared to have a significantly decreased particle size after 20h of ball-milling treatment. Micronized fibers showed reduced phenolic contents and antioxidant capacity compared to the results for untreated fibers. An increased level of PHB was also detected. Micronization introduces structural changes in fiber constituents (cellulose, hemicellulose, pectin, lignin, PHB) and micronized fibers exhibit more functional groups (hydroxyl, carboxyl) derived from those constituents. It is thus concluded that micronization treatments improve the functional properties of the fiber components.

  17. Wee Recyclers. An Activity Guide for Ages 3-5.

    ERIC Educational Resources Information Center

    Wisconsin State Dept. of Natural Resources, Madison.

    Recycling and reusing are skills that can be developed in early child care programs. This activity guide is intended to help teach children (ages 3-5) about recycling using simple, hands-on activities. Teacher-directed activities involve setting up a recycling center, sorting recyclable items, landfills, litter, a recycling alphabet, and ways that…

  18. 9 CFR 3.5 - Mobile or traveling housing facilities.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Transportation of Dogs and Cats 1 Facilities and Operating Standards § 3.5 Mobile or traveling housing facilities. (a) Heating, cooling, and temperature. Mobile or traveling housing facilities for dogs and cats must be sufficiently heated and cooled when necessary to protect the dogs and cats from temperature...

  19. 9 CFR 3.5 - Mobile or traveling housing facilities.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Transportation of Dogs and Cats 1 Facilities and Operating Standards § 3.5 Mobile or traveling housing facilities. (a) Heating, cooling, and temperature. Mobile or traveling housing facilities for dogs and cats must be sufficiently heated and cooled when necessary to protect the dogs and cats from temperature...

  20. 9 CFR 3.5 - Mobile or traveling housing facilities.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Transportation of Dogs and Cats 1 Facilities and Operating Standards § 3.5 Mobile or traveling housing facilities. (a) Heating, cooling, and temperature. Mobile or traveling housing facilities for dogs and cats must be sufficiently heated and cooled when necessary to protect the dogs and cats from temperature...

  1. 45 CFR 1210.3-5 - Preparation for appeal.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... SERVICE VISTA TRAINEE DESELECTION AND VOLUNTEER EARLY TERMINATION PROCEDURES VISTA Volunteer Early Termination § 1210.3-5 Preparation for appeal. (a) Entitlement to Representation. A Volunteer may be accompanied, represented and advised by a representative of the Volunteer's own choice at any stage of...

  2. 45 CFR 1210.3-5 - Preparation for appeal.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... SERVICE VISTA TRAINEE DESELECTION AND VOLUNTEER EARLY TERMINATION PROCEDURES VISTA Volunteer Early Termination § 1210.3-5 Preparation for appeal. (a) Entitlement to Representation. A Volunteer may be accompanied, represented and advised by a representative of the Volunteer's own choice at any stage of...

  3. 45 CFR 1210.3-5 - Preparation for appeal.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... SERVICE VISTA TRAINEE DESELECTION AND VOLUNTEER EARLY TERMINATION PROCEDURES VISTA Volunteer Early Termination § 1210.3-5 Preparation for appeal. (a) Entitlement to Representation. A Volunteer may be accompanied, represented and advised by a representative of the Volunteer's own choice at any stage of...

  4. 9 CFR 3.5 - Mobile or traveling housing facilities.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Transportation of Dogs and Cats 1 Facilities and Operating Standards § 3.5 Mobile or traveling housing facilities. (a) Heating, cooling, and temperature. Mobile or traveling housing facilities for dogs and cats must be sufficiently heated and cooled when necessary to protect the dogs and cats from temperature...

  5. Differentiating Instruction with Menus Grades 3-5: Math

    ERIC Educational Resources Information Center

    Westphal, Laurie E.

    2007-01-01

    "Differentiating Instruction With Menus Grades 3-5" offers teachers everything they need to create a student-centered learning environment based on choice. Addressing the four main subject areas (language arts, math, science, and social studies) and the major concepts taught within these areas, these books provide a number of different types of…

  6. Synthesis and biological evaluation of 3,5-dimethoxystilbene analogs

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In our continuing effort to discover natural product-based pest management agents, derivatives of 3,5-dimethoxystilbene were synthesized yielding 27 new and 6 known compounds. Of these, compounds 11 and 12 showed strong Aedes aegypti larvicidal activity (LC50 14.7 and 16.2 ppm, respectively). In fur...

  7. Science in Action Series: AGATE ( pt 3/5 )

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This show was made for the Office of Education at NASA Langley. The objective is to make math and science appealing to a middle school audience. This clip (pt 3/5 ) tells us more about the plane. How much will it cost to run, and how will we learn to fly?

  8. 43 CFR 9269.3-5 - Timber management.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Timber management. 9269.3-5 Section 9269.3... Timber management. (a) Sales of forest products; general. (b) Non-sale disposals; general—(1) Unauthorized cutting of timber-mineral and non-mineral lands. (i) The cutting or removing of the...

  9. Differentiating Instruction with Menus Grades 3-5: Science

    ERIC Educational Resources Information Center

    Westphal, Laurie E.

    2007-01-01

    "Differentiating Instruction With Menus Grades 3-5" offers teachers everything they need to create a student-centered learning environment based on choice. Addressing the four main subject areas (language arts, math, science, and social studies) and the major concepts taught within these areas, these books provide a number of different types of…

  10. Differentiating Instruction with Menus Grades 3-5: Language Arts

    ERIC Educational Resources Information Center

    Westphal, Laurie E.

    2007-01-01

    "Differentiating Instruction With Menus Grades 3-5" offers teachers everything they need to create a student-centered learning environment based on choice. Addressing the four main subject areas (language arts, math, science, and social studies) and the major concepts taught within these areas, these books provide a number of different types of…

  11. Differentiating Instruction with Menus Grades 3-5: Social Studies

    ERIC Educational Resources Information Center

    Westphal, Laurie E.

    2007-01-01

    "Differentiating Instruction With Menus Grades 3-5" offers teachers everything they need to create a student-centered learning environment based on choice. Addressing the four main subject areas (language arts, math, science, and social studies) and the major concepts taught within these areas, these books provide a number of different types of…

  12. 9 CFR 3.5 - Mobile or traveling housing facilities.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Transportation of Dogs and Cats 1 Facilities and Operating Standards § 3.5 Mobile or traveling housing facilities. (a) Heating, cooling, and temperature. Mobile or traveling housing facilities for dogs and cats must be sufficiently heated and cooled when necessary to protect the dogs and cats from temperature...

  13. Distonic biradical anions. Synthesis and characterization of the 3,5-dehydrophenyl and 1,3,5-trimethylenebenzene negative ions

    SciTech Connect

    Hu, J.; Squires, R.R.

    1996-06-19

    We recently described a new method for producing intense beams of structurally-defined biradical negative ions (`distonic radical anions`) in the gas phase based on reactions between trimethylsilyl-substituted carbanions and molecular fluorine. We now wish to report the extension of this procedure to the rational synthesis of negative ions of triradicals, i.e., `distonic biradical anions.` The significance of these species is manifold. Polyradicals and their associated ions are the central focus of current efforts to produce synthetic organic ferromagnets. In this report, we describe the gas-phase synthesis and characterization of 3,5-dehydrophenyl anion, 1, and 1,3,5-trimethylenebenzene negative ion, 2. Ion 1 corresponds to the negative ion of the ({sigma},{sigma},{sigma}) triradical 1,3,5-benzenetriyl, and it can also be viewed as a deprotonated m-benzyne. 29 refs.

  14. Abiotic transformation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by green rusts.

    PubMed

    Larese-Casanova, Philip; Scherer, Michelle M

    2008-06-01

    The rate and extent of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) transformation was measured in the presence of carbonate and sulfate green rust suspended in solutions containing common groundwater anions. Formaldehyde (HCHO), nitrous oxide gas (N2O(g)), and ammonium (NH4+) were the major end products, accounting for about 70% of the carbon mass balance and about half of the nitrogen mass balance. Results from experiments with both 14C-RDX and LC-MS analysis indicate that the remaining carbon products are soluble and most likely small (< 50 Da). The transient appearance of 1,3-dinitro-5-nitroso-1,3,5-triazacyclohexane (MNX), 1,3-dinitroso-5-nitro-1,3,5-triazacyclohexane (DNX), and 1,3,5-trinitroso-1,3,5-triazacyclohexane (TNX) indicate that some nitro-group reduction occurred. The kinetics of RDX transformation was rapid with a half-life of less than an hour in a pH 7.0 KBr solution. Little difference in rates of RDX transformation or product distribution was observed between carbonate and sulfate green rust, and an apparent reaction order of 1.0 was measured with respect to Fe(II) in both green rusts. Phosphate anions completely inhibited RDX reduction, and carbonate and sulfate anions resulted in slower kinetics, and in some cases, an initial lag period, compared to bromide and chloride. Our results suggest that green rusts may contribute to abiotic natural attenuation of RDX in Fe-rich subsurface environments, but that it will be important to consider groundwater composition when assessing rates of attenuation.

  15. Sulfuric acid cloud interpretation of the infrared spectrum of Venus

    NASA Technical Reports Server (NTRS)

    Martonchik, J. V.

    1974-01-01

    Sulfuric acid single-cloud models are compared with the Venus spectrum in the 8-14 micron region. The results indicate that a cloud composed of a 75 percent H2SO4 solution and with a particle density of 100 per cu cm is in good agreement with observations. In addition to explaining the 11.2 micron absorption, this model also predicts an absorption feature at 16.7 microns which should be detectable if the observation is made from an aircraft.

  16. IS THE TWO MICRON ALL SKY SURVEY CLUSTERING DIPOLE CONVERGENT?

    SciTech Connect

    Bilicki, Maciej; Chodorowski, Michal; Jarrett, Thomas; Mamon, Gary A.

    2011-11-01

    There is a long-standing controversy about the convergence of the dipole moment of the galaxy angular distribution (the so-called clustering dipole). Is the dipole convergent at all, and if so, what is the scale of the convergence? We study the growth of the clustering dipole of galaxies as a function of the limiting flux of the sample from the Two Micron All Sky Survey (2MASS). Contrary to some earlier claims, we find that the dipole does not converge before the completeness limit of the 2MASS Extended Source Catalog, i.e., up to 13.5 mag in the near-infrared K{sub s} band (equivalent to an effective distance of 300 Mpc h{sup -1}). We compare the observed growth of the dipole with the theoretically expected, conditional one (i.e., given the velocity of the Local Group relative to the cosmic microwave background), for the {Lambda}CDM power spectrum and cosmological parameters constrained by the Wilkinson Microwave Anisotropy Probe. The observed growth turns out to be within 1{sigma} confidence level of its theoretical counterpart once the proper observational window of the 2MASS flux-limited catalog is included. For a contrast, if the adopted window is a top hat, then the predicted dipole grows significantly faster and converges (within the errors) to its final value for a distance of about 300 Mpc h{sup -1}. By comparing the observational windows, we show that for a given flux limit and a corresponding distance limit, the 2MASS flux-weighted window passes less large-scale signal than the top-hat one. We conclude that the growth of the 2MASS dipole for effective distances greater than 200 Mpc h{sup -1} is only apparent. On the other hand, for a distance of 80 Mpc h{sup -1} (mean depth of the 2MASS Redshift Survey) and the {Lambda}CDM power spectrum, the true dipole is expected to reach only {approx}80% of its final value. Eventually, since for the window function of 2MASS the predicted growth is consistent with the observed one, we can compare the two to evaluate

  17. Improvements to the Apache Point 3.5-m primary-mirror support system

    NASA Astrophysics Data System (ADS)

    Brown, Yorke J.; Davis, Jon E.

    1998-05-01

    The primary mirror of the Apache Point 3.5 meter telescope rests on an array of small pneumatic actuators distributed over the back plate of the mirror and within its honey comb cells. A control system constantly adjusts the pressure in the actuators so as to synthesize a perfectly rigid mounting, thus maintaining both the figure of the mirror and its orientation with respect to the mirror cell. In its original configuration, the APO 3.5 meter system exhibited a number of anomalous behaviors that detracted from the optical performance of the telescope. Analysis of the design indicated three basic problems: first that the pneumatic servovalves suffered from mechanical nonlinearities and an adverse dependence of their transfer function on operating pressure; second, that the air supply system could not exhaust air from the actuators rapidly enough near the horizon and zenith; and third, that the control system did not adequately account for the inertia of the mirror under dynamic conditions. Consequently, we have designed and installed a new control system which addresses these deficiencies. The new system employs high-bandwidth, flapper-type proportional valves that eliminate the mechanical problems and permit implementation of a high- performance controller. The new controller utilizes the existing hard points for mirror position sensing, but implements a pressure-feedback inner loop and a more sophisticated dynamic model. The air supply system now incorporates a sub-atmospheric return and operates closed- loop to minimize contamination problems. The new system exhibits substantial improvements over its previous performance, with positioning errors in the sub-micron range. The design has been selected for use on the Sloan Digital Sky Survey telescope.

  18. Investigation of dislocation behavior in micron and sub-micron thin films

    NASA Astrophysics Data System (ADS)

    Hunter, Abigail

    Plastic deformation in crystalline materials is mediated by dislocation motion and their interaction with defects, such as second phase particles, dislocations, grain boundaries and voids. In addition, grain boundaries, free and passivated surfaces have a significant impact on the evolution of dislocations and their intricate structures. In polycrystalline materials, the influence of dislocation motion and interactions results in unique mechanical properties, such as high yield stress and fracture strength and a dependency on grain size. It is observed that for an average grain size in the micron and sub-micron regime, the yield stress increases as the grain size decreases following a power law. This size effect is known as Hall Petch effect. A reliable computational model that describes the mechanical response and failure mechanisms of micron and sub-micron scale devices should incorporate these size effects. A three-dimensional phase field dislocation dynamics model (3D PFDD) is developed. This is a dislocation based plasticity model that accounts for the motion and interactions of individual dislocations with material defects and interfaces, such as obstacles, and grain boundaries. This model is a valuable and efficient research tool that will help to understand plastic deformation on the mesoscopic level, bridging the gap between microscopic and macroscopic studies. For the research presented here, this model is used specifically to understand and simulate dislocation behavior in fcc (face-centered cubic) metal thin films, similar to those used in micro-electro-mechanical systems (MEMS). Incorporating microstructure, such as grain boundaries, is key to accurately predicting deformation behavior in any system. Plastic deformation is affected by both the thickness of the film layers and by the resolution of the film's internal microstructure. In MEMS devices and components that are generally on the micron scale (hundreds of microns in size), the internal

  19. Three-micron spectroscopy of highly reddened field stars

    NASA Technical Reports Server (NTRS)

    Tapia, Mauricio; Persi, P.; Roth, M.; Ferrari-Toniolo, M.

    1989-01-01

    Broad absorption features centered at 3.45 microns and at 3.0-3.0 microns towards a number of late-type supergiants in the vicinity of the galactic center were repeatedly reported. Here, 2.0 to 2.5 and 3.0 to 4.0 micron spectra are presented for field late-type highly reddened (A sub V is approximately 17-27) stars located in different regions of the galactic plane more than 20 deg away from the galactic center direction. The observations, made with the 3.6, 2.2, and 1.0 m ESO telescopes at La Silla, Chile, consists of CVF spectra with resolution lambda/delta lambda is approximately or equal to 100 and IRSPEC spectra with resolution lambda/delta lambda is approximately or equal to 700. In the direction of the most highly reddened stars, definitive detections of the 3.45 and the 3.0 to 3.1 micron absorption features are reported. The 3.45 micron feature was attributed to absorption arising in a vibrational transition resulting from the C-H stretching in organic compounds, while the 3.0 to 3.1 micron broader feature are tentatively attributed to O-H bonds. The observations strongly support that the agent producing the 3.45 micron feature, presumably organic molecules, is an important component of the diffuse interstellar medium and is not characteristic only of the galactic center environment.

  20. Synthetic routes to 3(5)-phosphonylated pyrazoles

    NASA Astrophysics Data System (ADS)

    Goulioukina, N. S.; Makukhin, N. N.; Beletskaya, I. P.

    2016-07-01

    This review comprehensively covers the currently available synthetic routes to 3(5)-phosphonylated pyrazoles. There are demonstrated significant advances in this field over the last 10–15 years caused by the use of the Bestmann–Ohira reagent [as well as (diazomethyl)phosphonates and phosphonylated hydrazonoyl halides] in reactions with diverse dipolarophiles. 1,3-Dipolar cycloaddition of diazo compounds to α,β-unsaturated phosphonates as well as intramolecular heterocyclization of (1-diazoallyl)phosphonates and (3--diazo-1-propenyl)phosphonates are discussed. Synthetic potential of cyclocondensation of organophosphorus 1,3-dielectrophilic compounds with hydrazines is shown. Ways to introduce a phosphonate group into the pyrazole ring are considered. Examples of chemical transformations of 3(5)-phosphonylated pyrazoles are reported. The bibliography includes 88 references.

  1. Synthetic routes to 3(5)-phosphonylated pyrazoles

    NASA Astrophysics Data System (ADS)

    Goulioukina, N. S.; Makukhin, N. N.; Beletskaya, I. P.

    2016-07-01

    This review comprehensively covers the currently available synthetic routes to 3(5)-phosphonylated pyrazoles. There are demonstrated significant advances in this field over the last 10-15 years caused by the use of the Bestmann-Ohira reagent [as well as (diazomethyl)phosphonates and phosphonylated hydrazonoyl halides] in reactions with diverse dipolarophiles. 1,3-Dipolar cycloaddition of diazo compounds to α,β-unsaturated phosphonates as well as intramolecular heterocyclization of (1-diazoallyl)phosphonates and (3--diazo-1-propenyl)phosphonates are discussed. Synthetic potential of cyclocondensation of organophosphorus 1,3-dielectrophilic compounds with hydrazines is shown. Ways to introduce a phosphonate group into the pyrazole ring are considered. Examples of chemical transformations of 3(5)-phosphonylated pyrazoles are reported. The bibliography includes 88 references.

  2. Dendrimers Based on [1,3,5]-Triazines

    PubMed Central

    STEFFENSEN, MACKAY B.; HOLLINK, EMILY; KUSCHEL, FRANK; BAUER, MONIKA; SIMANEK, ERIC E.

    2009-01-01

    A comprehensive and chronological account of dendrimers based on [1,3,5]-triazines is provided. Synthetic strategies to install the triazine through cycloaddition, cyclotrimerization, and nucleophilic aromatic substitution of cyanuric chloride are discussed. Motivations and applications of these architectures are surveyed, including the preparation of supra-molecular assemblies in the solution and solid states and their use in medicines, advanced materials, and separations when anchored to solid supports. PMID:19953202

  3. Practical auxiliary basis implementation of Rung 3.5 functionals

    SciTech Connect

    Janesko, Benjamin G.; Scalmani, Giovanni; Frisch, Michael J.

    2014-07-21

    Approximate exchange-correlation functionals for Kohn-Sham density functional theory often benefit from incorporating exact exchange. Exact exchange is constructed from the noninteracting reference system's nonlocal one-particle density matrix γ(r{sup -vector},r{sup -vector}′). Rung 3.5 functionals attempt to balance the strengths and limitations of exact exchange using a new ingredient, a projection of γ(r{sup -vector},r{sup -vector} ′) onto a semilocal model density matrix γ{sub SL}(ρ(r{sup -vector}),∇ρ(r{sup -vector}),r{sup -vector}−r{sup -vector} ′). γ{sub SL} depends on the electron density ρ(r{sup -vector}) at reference point r{sup -vector}, and is closely related to semilocal model exchange holes. We present a practical implementation of Rung 3.5 functionals, expanding the r{sup -vector}−r{sup -vector} ′ dependence of γ{sub SL} in an auxiliary basis set. Energies and energy derivatives are obtained from 3D numerical integration as in standard semilocal functionals. We also present numerical tests of a range of properties, including molecular thermochemistry and kinetics, geometries and vibrational frequencies, and bandgaps and excitation energies. Rung 3.5 functionals typically provide accuracy intermediate between semilocal and hybrid approximations. Nonlocal potential contributions from γ{sub SL} yield interesting successes and failures for band structures and excitation energies. The results enable and motivate continued exploration of Rung 3.5 functional forms.

  4. Removing 3,5-Dichlorophenol from Wastewater by Alternative Adsorbents

    NASA Astrophysics Data System (ADS)

    Kobetičová, Hana; Galbičková, Blanka; Ševčíková, Janka; Soldán, Maroš

    2014-12-01

    The main objective of this paper is to evaluate an efficiency of 3,5 - dichlorophenol removal from wastewater by using alternative adsorbents. Chlorophenols are organic compounds consisting of a benzene ring, OH groups and also atoms of chlorine. Chlorophenols may have a huge isomere variety that means there are differences in their chemical and physical properties. Due to their toxicity it is necessary to remove them from waste water and in this paper an alternative way of such process is described.

  5. Retrieval of atomic oxygen and temperature in the thermosphere. I - Feasibility of an experiment based on the spectrally resolved 147 micron limb emission

    NASA Astrophysics Data System (ADS)

    Zachor, A. S.; Sharma, R. D.

    1989-11-01

    Consideration is given to the possibility of recovering vertical profiles of the temperature and O-atom density from limb scan data obtained near 147 and/or 63 microns wavelength. It is shown that the two vertical profiles may be recovered by applying an onion-peeling method to synthetic data. The temperature and O-atom density are obtained simultaneously by a nonlinear least-squares spectrum fitting. It is found that spectral data in the 147-micron line from 300 km down to 130-90 km in altitude produces better results than the 63-micron data below 140 km. It is suggested that a confocal Fabry-Perot system operating near 147 microns could provide the S/N ratio and spectral resolution needed for successful retrievals. Retrievals down to 90 km from data obtained at orbital altitude would require cooled foreoptics with a diameter of about 1 meter.

  6. Cloud properties inferred from 8-12 micron data

    NASA Technical Reports Server (NTRS)

    Strabala, Kathleen I.; Ackerman, Steven A.; Menzel, W. Paul

    1994-01-01

    A trispectral combination of observations at 8-, 11-, and 12-micron bands is suggested for detecting cloud and cloud properties in the infrared. Atmospheric ice and water vapor absorption peak in opposite halves of the window region so that positive 8-minus-11-micron brightness temperature differences indicate cloud, while near-zero or negative differences indicate clear regions. The absorption coefficient for water increases more between 11 and 12 microns than between 8 and 11 microns, while for ice, the reverse is true. Cloud phases is determined by a scatter diagram of 8-minus-11-micron versus 11-minus-12-micron brightness temperature differences; ice cloud shows a slope greater than 1 and water cloud less than 1. The trispectral brightness temperature method was tested upon high-resolution interferometer data resulting in clear-cloud and cloud-phase delineation. Simulations using differing 8-micron bandwidths revealed no significant degradation of cloud property detection. Thus, the 8-micron bandwidth for future satellites can be selected based on the requirements of other applications, such as surface characterization studies. Application of the technique to current polar-orbiting High-Resolution Infrared Sounder (HIRS)-Advanced Very High Resolution Radiometer (AVHRR) datasets is constrained by the nonuniformity of the cloud scenes sensed within the large HIRS field of view. Analysis of MAS (MODIS Airborne Simulator) high-spatial resolution (500 m) data with all three 8-, 11-, and 12-micron bands revealed sharp delineation of differing cloud and background scenes, from which a simple automated threshold technique was developed. Cloud phase, clear-sky, and qualitative differences in cloud emissivity and cloud height were identified on a case study segment from 24 November 1991, consistent with the scene. More rigorous techniques would allow further cloud parameter clarification. The opportunities for global cloud delineation with the Moderate-Resolution Imaging

  7. Spectrum Recombination.

    ERIC Educational Resources Information Center

    Greenslade, Thomas B., Jr.

    1984-01-01

    Describes several methods of executing lecture demonstrations involving the recombination of the spectrum. Groups the techniques into two general classes: bringing selected portions of the spectrum together using lenses or mirrors and blurring the colors by rapid movement or foreshortening. (JM)

  8. Effect of mycorrhizal fungi on the phytoremediation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX).

    PubMed

    Thompson, Phillip L; Polebitski, Austin S

    2010-02-01

    The objective of this research was to decrease the bioaccumulation of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) in the leaves of switchgrass (Panicum virgatum) and hybrid poplar trees (Populus deltoides x nigra, DN34) by exploiting the symbiotic relationship between these plants and mycorrhizal fungi. Prior to dosing with uniformly labeled (14)C-RDX, plants were grown for three months to establish the symbiosis. Results showed that the presence of mycorrhizal fungi does not significantly decrease the concentration of RDX in leaf tissues for experimental periods of 30 days. Results also indicated that a radiolabeled volatile organic compound was emitted by both plant species. This is the first evidence that a whole plant can facilitate the transformation of RDX to a volatile organic chemical.

  9. Electrochemical reduction of hexahydro-1,3,5-trinitro-1,3,5-triazine in aqueous solutions.

    PubMed

    Bonin, Pascale M L; Bejan, Dorin; Schutt, Leah; Hawari, Jalal; Bunce, Nigel J

    2004-03-01

    Electrochemical reduction of RDX, hexahydro-1,3,5-trinitro-1,3,5-triazine, a commercial and military explosive, was examined as a possible remediation technology for treating RDX-contaminated groundwater. A cascade of divided flow-through cells was used, with reticulated vitreous carbon cathodes and IrO2/Ti dimensionally stable anodes, initially using acetonitrile/water solutions to increase the solubility of RDX. The major degradation pathway involved reduction of RDX to the corresponding mononitroso compound, followed by ring cleavage to yield formaldehyde and methylenedinitramine. The reaction intermediates underwent further reduction and/or hydrolysis, the net result being the complete transformation of RDX to small molecules. The rate of degradation increased with current density, but the current efficiency was highest at low current densities. The technique was extended successfully both to 100% aqueous solutions of RDX and to an undivided electrochemical cell.

  10. Apparatus for handling micron size range particulate material

    NASA Technical Reports Server (NTRS)

    Friichtenicht, J. F.; Roy, N. L. (Inventor)

    1968-01-01

    An apparatus for handling, transporting, or size classifying comminuted material was described in detail. Electrostatic acceleration techniques for classifying particles as to size in the particle range from 0.1 to about 100 microns diameter were employed.

  11. Release of Micronized Copper Particles from Pressure Treated Wood Products.

    EPA Science Inventory

    Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about possible human or environmental exposure. Two common pathways ...

  12. Injection Seeded/Phase-Conjugated 2-micron Laser System

    NASA Technical Reports Server (NTRS)

    Bai, Yingxin; Yu, Jirong; Petros,M.; Petzar, Paul; Trieu, Bo; Lee, Hyung; Singh, U.; Leyva, V.; Shkunov, V.; Rockwell, D.; Betin, A.; Wang, J.

    2007-01-01

    For the first time, beam quality improvement of 2 micron laser using a fiber based phase conjugation mirror has been demonstrated. Single frequency operation is necessary to lower threshold. The reflectivity of PCM is approx. 50%.

  13. Laser materials for the 0.67-microns to 2.5-microns range

    NASA Technical Reports Server (NTRS)

    Toda, Minoru; Zamerowski, Thomas J.; Ladany, Ivan; Martinelli, Ramon U.

    1987-01-01

    Basic requirements for obtaining injection laser action in III-V semiconductors are discussed briefly. A detailed review is presented of materials suitable for lasers emitting at 0.67, 1.44, 1.93, and 2.5 microns. A general approach to the problem is presented, based on curves of materials properties published by Sasaki et al. It is also shown that these curves, although useful, may need correction in certain ranges. It is deduced that certain materials combinations, either proposed in the literature or actually tried, are not appropriate for double heterostructure lasers, because the refractive index of the cladding material is higher than the index of the active material, thus resulting in no waveguiding, and high threshold currents. Recommendations are made about the most promising approach to the achievement of laser action in the four wavelengths mentioned above.

  14. The size of NGC 1068 at 10 microns

    NASA Technical Reports Server (NTRS)

    Becklin, E. E.; Neugebauer, G.; Matthews, K.; Wynn-Williams, C. G.

    1973-01-01

    The data presented show that a majority of the 10-micron emission from NGC 1068 comes from an area with a diameter of about 60 pc. The measurements described were made at 10 microns on two nights at the 200-inch Hale telescope. The data obtained agree with the results obtained by Stein et al. (1973). An approach to reconcile the new data with the variability observed by Rieke and Low (1972) is also discussed.

  15. High-resolution maps of Jupiter at five microns.

    NASA Technical Reports Server (NTRS)

    Keay, C. S. L.; Low, F. J.; Rieke, G. H.; Minton, R. B.

    1973-01-01

    The distribution of 5-micron radiation, emitted from a large number of discrete sources from Jupiter, was observed during the 1972 apparition. These sources are less bright than those observed by Westphal (1969). At least 50 discrete sources having brightness temperatures exceeding 227 K were revealed which were mainly located within three narrow-latitude bands. Strong correlation exists between the 5-micron brightness temperatures of Jovian features and their colors as recorded photographically.

  16. Micron Accuracy Deployment Experiment (MADE), phase A. Volume 1

    NASA Technical Reports Server (NTRS)

    Peterson, Lee D.; Lake, Mark S.

    1995-01-01

    This report documents a Phase A In-STEP flight experiment development effort. The objective of the experiment is to deploy a portion of a segmented reflector on the Shuttle and study its micron-level mechanics. Ground test data are presented which projects that the on-orbit precision of the test article should be approximately 5 microns. Extensive hardware configuration development information is also provided.

  17. 1,3,5-Hydroxybenzene structures in mosses

    USGS Publications Warehouse

    Wilson, M.A.; Sawyer, J.; Hatcher, P.G.; Lerch, H. E.

    1989-01-01

    A number of mosses from widely different families have been studied by cross polarization solid state 13C NMR spectroscopy. Although polysaccharide-type materials dominate the NMR spectra, significant amounts of aromatic carbons are observed in some mosses. Some of this material can be removed by ultrasonic bath treatment, and is lignin derived, probably from impurities from fine root material from associated higher plants. However other material is truly moss-derived and appears to be from 1,3,5-hydroxybenzene structures. This is inconsistent with lignin as being a component of mosses, and suggests a tannin or hydroxybenzofuran polymer is responsible for moss rigidity. ?? 1989.

  18. Delayed myelosuppression with acute exposure to hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and environmental degradation product hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) in rats

    SciTech Connect

    Jaligama, Sridhar; Kale, Vijay M.; Wilbanks, Mitchell S.; Perkins, Edward J.; Meyer, Sharon A.

    2013-02-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), a widely used munitions compound, and hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX), its N-nitroso product of anaerobic microbial nitroreduction, are contaminants of military sites. Previous studies have shown MNX to be the most acutely toxic among the nitroreduced degradation products of RDX and to cause mild anemia at high dose. The present study compares hematotoxicity with acute oral exposure to MNX with parent RDX. Both RDX and MNX caused a modest decrease in blood hemoglobin and ∼ 50% loss of granulocytes (NOAELs = 47 mg/kg) in female Sprague–Dawley rats observed 14 days post-exposure. We explored the possibility that blood cell loss observed after 14 days was delayed in onset because of toxicity to bone marrow (BM) progenitors. RDX and MNX decreased granulocyte/macrophage-colony forming cells (GM-CFCs) at 14, but not 7, days (NOAELs = 24 mg/kg). The earliest observed time at which MNX decreased GM-CFCs was 10 days post-exposure. RDX and MNX likewise decreased BM burst-forming units-erythroid (BFU-Es) at 14, but not 7, days. Granulocyte–erythrocyte–monocyte–megakaryocyte (GEMM)-CFCs were unaffected by RDX and MNX at 7 days suggesting precursor depletion did not account for GM-CFC and BFU-E loss. MNX added to the culture media was without effect on GM-CFC formation indicating no direct inhibition. Flow cytometry showed no differential loss of BM multilineage progenitors (Thy1.1{sup +}) or erythroid (CD71{sup +}) precursors with MNX suggesting myeloid and erythroid lineages were comparably affected. Collectively, these data indicate that acute exposure to both RDX and MNX caused delayed suppression of myelo- and erythropoiesis with subsequent decrease of peripheral granulocytes and erythrocytes. Highlights: ► Acute oral exposure to munitions RDX causes myelosuppression. ► Environmental degradation product MNX is comparable in effect. ► RDX and MNX are cytotoxic to both myeloid and erythroid

  19. The WIN 3.5 meter telescope project

    NASA Astrophysics Data System (ADS)

    Johns, Matt; Pilachowski, Caty

    1990-07-01

    The University of Wisconsin-Indiana University-National Optical Astronomy Observatories ('WIN') 3.5-m aperture telescope project's design concepts and development status are assessed. The WIN telescope employs a wide field of view in order to take advantage of recent advancements in multiobject fiber-optic spectroscopy. A novel support system is under development for the borosilicate honeycomb primary mirror blank which acts solely on the mirror's rear surface; mirror temperature will be actively controlled. The WIN telescope's control system will use a distributed, easily expanded and upgraded network of microprocessors connected to a master computer via serial bus.

  20. Micronized Organic Magnesium Salts Enhance Opioid Analgesia in Rats

    PubMed Central

    Bujalska-Zadrożny, Magdalena; Kulik, Kamila; Ordak, Michał; Sasinowska-Motyl, Małgorzata; Gąsińska, Emilia; de Corde, Anna; Kowalczyk, Agnieszka; Sacharczuk, Mariusz; Naruszewicz, Marek

    2016-01-01

    Purpose As previously reported, magnesium sulphate administered parenterally significantly increased an opioid antinociception in different kinds of pain. Since the typical form of magnesium salts are poorly and slowly absorbed from the gastrointestinal tract we examined whether their micronized form could increase opioids induced antinociception. Methods In behavioural studies on rats morphine, tramadol and oxycodone together with magnesium (lactate dihydrate, hydroaspartate, chloride) in micronized (particles of size D90 < 50 μm) and conventional forms were used. Changes in pain thresholds were determined using mechanical stimuli. The intestinal absorption of two forms of magnesium lactate dihydrate (at the doses of 7.5 or 15 mg ions) in the porcine gut sac model were also compared. Results Micronized form of magnesium lactate dihydrate or hydroaspartate but not chloride (15 mg of magnesium ions kg-1) enhanced the analgesic activity of orally administered opioids, significantly faster and more effective in comparison to the conventional form of magnesium salts (about 40% for oxycodone administered together with a micronized form of magnesium hydroaspartate). Moreover, in vitro studies of transport across porcine intestines of magnesium ions showed that magnesium salts administered in micronized form were absorbed from the intestines to a greater extent than the normal form of magnesium salts. Conclusions The co-administration of micronized magnesium organic salts with opioids increased their synergetic analgesic effect. This may suggest an innovative approach to the treatment of pain in clinical practice. PMID:27792736

  1. Laser damage tests on InSb photodiodes at 1.064 micron and 0.532 micron

    NASA Technical Reports Server (NTRS)

    Bearman, G. H.; Staller, C.; Mahoney, C.

    1992-01-01

    InSb photodiodes were examined for performance degradation after pulsed laser illumination at 0.532 micron and 1.064 micron. Incident laser powers ranged from 6 x 10 exp-18 micron-watts to 16 micron-watts in a 50 pm diameter spot. Dark current and spectral response were both measured before and after illumination. Dark current measurements were taken with the diode blanked off and viewing only 77 K surfaces. Long term stability tests demonstrated that the blackbody did not exhibit long term drifts. Other tests showed that room temperature variations did not affect the diode signal chain or the digitization electronics used in data acquisition. Results of the experiment show that the diodes did not exhibit changes in dark current or spectral response performance as a result of the laser illumination. A typical change in diode spectral response (before/after laser exposure) was about 0.2 percent +/- 0.2 percent.

  2. Prescribed 3-D Direct Writing of Suspended Micron/Sub-micron Scale Fiber Structures via a Robotic Dispensing System

    PubMed Central

    Yuan, Hanwen; Cambron, Scott D.; Keynton, Robert S.

    2015-01-01

    A 3-axis dispensing system is utilized to control the initiating and terminating fiber positions and trajectory via the dispensing software. The polymer fiber length and orientation is defined by the spatial positioning of the dispensing system 3-axis stages. The fiber diameter is defined by the prescribed dispense time of the dispensing system valve, the feed rate (the speed at which the stage traverses from an initiating to a terminating position), the gauge diameter of the dispensing tip, the viscosity and surface tension of the polymer solution, and the programmed drawing length. The stage feed rate affects the polymer solution’s evaporation rate and capillary breakup of the filaments. The dispensing system consists of a pneumatic valve controller, a droplet-dispensing valve and a dispensing tip. Characterization of the direct write process to determine the optimum combination of factors leads to repeatedly acquiring the desired range of fiber diameters. The advantage of this robotic dispensing system is the ease of obtaining a precise range of micron/sub-micron fibers onto a desired, programmed location via automated process control. Here, the discussed self-assembled micron/sub-micron scale 3D structures have been employed to fabricate suspended structures to create micron/sub-micron fluidic devices and bioengineered scaffolds. PMID:26132732

  3. The NEWFIRM HETDEX Survey - Studying Galaxy Growth with 400,000 Galaxies at 2 < z < 3.5

    NASA Astrophysics Data System (ADS)

    Stevans, Matthew L.; Finkelstein, S. L.; Gebhardt, K.; Jogee, S.; Papovich, C. J.; Ciardullo, R.; Gronwall, C.; Acquaviva, V.; Weinzirl, T.; HETDEX

    2014-01-01

    We present the NEWFIRM HETDEX survey - a K-band survey with NEWFIRM on the KPNO 4m Mayall telescope of a 28 deg^2 region of the Hobby Eberly Telescope Dark Energy Experiment (HETDEX) equatorial field. Here we provide the survey plan, as well as results from the first year (out of four) of our survey. When combined with deep ugriz images from the Dark Energy Camera, deep 3.6 and 4.5 micron images from Spitzer/IRAC, deep far-IR imaging at 250, 350, and 500 microns from HERSCHEL-SPIRE, and R ~ 800 integral-field spectroscopy from the Hobby-Eberly Telescope's VIRUS spectrographs (filling factor 1:1), our observations will allow extinction-corrected star-formation rates (SFRs) to be obtained for ~400,000 galaxies at 2 < z < 3.5. Our survey covers a co-moving volume of 0.5 Gpc^3 and is sensitive to SFRs down to 10 Msol/yr, covering a 10-100 times larger volume and going three times deeper than previous surveys. Our very large volume will allow us to explore galaxy growth as a function of stellar mass, halo mass, and local environment, in addition to providing K-band legacy data for the field.

  4. DFT STUDY OF CO AND NO ADSORPTION ON BORON NITRIDE (BN)n = 3 - 5 NANOCLUSTERS

    NASA Astrophysics Data System (ADS)

    Zahedi, Ehsan; Pangh, Abdolhakim; Ghorbanpour, Hamed

    2015-11-01

    Interaction of CO and NO molecules by different orientations on (BN)n=3-5 clusters have been studied at the B3LYP/6-311+G* level of theory. Total electronic energies have been corrected for geometrical counterpoise (gCP) and dispersion (D3) energies at the B3LYP/6-31G* level. Formation of a new sigma bond between the gas and (BN)3 cluster, atom in molecules (AIM) results, density of states spectrums (DOS), molecular electrostatic potential (MEP) surfaces, and visualization of wave function of molecular orbitals in the nearest bonding regions to the Fermi level have confirmed that adsorption of CO by carbon end atom, and NO by nitrogen end atom is covalent in nature, so that the charge transfer is occurred from gas molecule to the cluster.

  5. Beam assisted fabrication of 3-5/Si monolithic devices

    NASA Astrophysics Data System (ADS)

    Robinson, Gary Y.; Collins, George J.; Solanki, Raj

    1989-05-01

    The results of a two-year project to explore new methods for deposition of 3-5 semiconducting film on silicon substrates are summarized. Gas-source molecular beam epitaxy was used for the first time to achieve heteroepitaxy of InP on Si. The InP films contain low concentrations of impurities (less than 400 ppb), luminescence under optical excitation, and exhibit high structural quality. Laser-assisted epitaxy was used for selective area growth of GaP and InP on Si using a new phosphorous precursor, and in situ removal of oxide on Si was achieved photochemically. Plasma-assisted chemical vapor deposition of AlN films has been carried out at low substrate temperatures using an electron beam to excite a remote plasma.

  6. Molecular dynamics characterization of void defects in crystalline (1,3,5-trinitro-1,3,5-triazacyclohexane).

    PubMed

    Boyd, Sylke; Murray, Jane S; Politzer, Peter

    2009-11-28

    In the context of a continuing investigation of factors that affect the sensitivities of energetic materials to detonation initiation, we have carried out a molecular dynamics characterization of void defects in crystalline (1,3,5-trinitro-1,3,5-triazacyclo-hexane). An empirical force field that is capable of handling flexible molecules in a pliable crystal was used. Voids ranging in size from 2 to 30 adjacent vacated sites were created in model lattices of 216 or 512 molecules. Energetic and geometric ground state properties were determined. The void formation energy per molecule removed was found to decrease from 50 kcal/mol for a single vacancy to about 23+/-2 kcal/mol for voids larger than one unit cell (8 molecules). Analysis of the local binding energies in the vicinity of a void reveals not only the expected decrease for molecules directly on the void surface but also a wide spread of values in the first 5-10 A away from the surface; this includes some molecules with local binding energies significantly higher than in the defect-free lattice. Molecular conformational changes and reorientations begin to be found in the vicinities of voids larger than one unit cell. Thermal behavior investigated includes void and molecular diffusion coefficients and fluctuations in void size. PMID:19947705

  7. Dissociative electron attachment to the nitroamine HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine).

    PubMed

    Postler, Johannes; Goulart, Marcelo M; Matias, Carolina; Mauracher, Andreas; Ferreira da Silva, Filipe; Scheier, Paul; Limão-Vieira, Paulo; Denifl, Stephan

    2013-05-01

    In the present study, dissociative electron attachment (DEA) measurements with gas phase HMX, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine, C4H8N8O8, have been performed by means of a crossed electron-molecular beam experiment. The most intense signals are observed at 46 and 176 u and assigned to NO2(-) and C3H6N5O4(-), respectively. Anion efficiency curves for 15 negatively charged fragments have been measured in the electron energy region from about 0-20 eV with an energy resolution of ~0.7 eV. Product anions are observed mainly in the low energy region, near 0 eV, arising from surprisingly complex reactions associated with multiple bond cleavages and structural and electronic rearrangement. The remarkable instability of HMX towards electron attachment with virtually zero kinetic energy reflects the highly explosive nature of this compound. Substantially different intensity ratios of resonances for common fragment anions allow distinguishing the nitroamines HMX and royal demolition explosive molecule (RDX) in negative ion mass spectrometry based on free electron capture.

  8. Microbially Mediated Biodegradation of Hexahydro-1,3,5-Trinitro-1,3,5- Triazine by Extracellular Electron Shuttling Compounds

    PubMed Central

    Kwon, Man Jae; Finneran, Kevin T.

    2006-01-01

    The potential for humic substances to stimulate the reduction of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) was investigated. This study describes a novel approach for the remediation of RDX-contaminated environments using microbially mediated electron shuttling. Incubations without cells demonstrated that reduced AQDS transfers electrons directly to RDX, which was reduced without significant accumulation of the nitroso intermediates. Three times as much reduced AQDS (molar basis) was needed to completely reduce RDX. The rate and extent of RDX reduction differed greatly among electron shuttle/acceptor amendments for resting cell suspensions of Geobacter metallireducens and G. sulfurreducens with acetate as the sole electron donor. AQDS and purified humic substances stimulated the fastest rate of RDX reduction. The nitroso metabolites did not significantly accumulate in the presence of AQDS or humic substances. RDX reduction in the presence of poorly crystalline Fe(III) was relatively slow and metabolites transiently accumulated. However, adding humic substances or AQDS to Fe(III)-containing incubations increased the reduction rates. Cells of G. metallireducens alone reduced RDX; however, the rate of RDX reduction was slow relative to AQDS-amended incubations. These data suggest that extracellular electron shuttle-mediated RDX transformation is not organism specific but rather is catalyzed by multiple Fe(III)- and humic-reducing species. Electron shuttle-mediated RDX reduction may eventually become a rapid and effective cleanup strategy in both Fe(III)-rich and Fe(III)-poor environments. PMID:16957213

  9. Visibility related to backscatter at 1.54 micron

    NASA Technical Reports Server (NTRS)

    Barber, T. L.; Larson, D. R.

    1986-01-01

    The lidar process was shown to have the necessary potential to fulfill the need for a remote measurement of visibility. Visibility can be inferred from a lidar return optical extinction. The wavelength 1.54 micron was chosen, being near the visible wavelength region and having a high eye safety threshol, 200,000 times higher than 1.06 micron; 1.54 is the erbium laser wavelength. This research utilized 105 measured height profiles of natural droplet size distributions data, taken in clouds, fog, and haze. These profiles were examined to determine the completeness of the droplet counting data. It was found that the particle spectrometer data were incomplete in the very light ford and haze so this portion of the data was eliminated. Utilizing the Mie theory, these droplet size distribution profiles were converted to backscatter at 1.54 micron and extinction in the visible region, 0.55 micron. Using Koschmeider's relationship, the extinction profiles were converted to visibility. The visibility and backscatter profiles were compared to develop a relationship between visibility and backscatter at 1.54 micron.

  10. Toxicity of hexahydro-1,3,5-trinitro-1,3,5-triazine to larval zebrafish (Danio rerio)

    USGS Publications Warehouse

    Mukhi, S.; Pan, X.; Cobb, G.P.; Patino, R.

    2005-01-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine, a cyclonitramine commonly known as RDX, is used in the production of military munitions. Contamination of soil, sediment, and ground and surface waters with RDX has been reported in different places around the world. Acute and subacute toxicities of RDX have been relatively well documented in terrestrial vertebrates, but among aquatic vertebrates the information available is limited. The objective of this study was to characterize the acute toxicity of RDX to larval zebrafish. Mortality (LC50) and incidence of vertebral column deformities (EC50) were two of the end points measured in this study. The 96-h LC50 was estimated at 22.98 and 25.64 mg l-1 in two different tests. The estimated no-observed-effective- concentration (NOEC) values of RDX on lethality were 13.27 ?? 0.05 and 15.32 ?? 0.30 mg l-1; and the lowest-observed-effective- concentration (LOEC) values were 16.52 ?? 0.05 and 19.09 ?? 0.23 mg l-1 in these two tests, respectively. The 96-h EC50 for vertebral deformities on survivors from one of the acute lethality tests was estimated at 20.84 mg l-1, with NOEC and LOEC of 9.75 ?? 0.34 and 12.84 ?? 0.34 mg l-1, respectively. Behavioral aberrations were also noted in this acute toxicity study, including the occurrence of whirling movement and lethargic behavior. The acute effects of RDX on survival, incidence of deformities, and behavior of larval zebrafish occurred at the high end of the most frequently reported concentrations of RDX in aquatic environments. The chronic effects of RDX in aquatic vertebrates need to be determined for an adequate assessment of the ecological risk of environmental RDX. ?? 2005 Elsevier Ltd. All rights reserved.

  11. Toxicity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in three vertebrate species.

    PubMed

    Johnson, Mark S; McFarland, Craig A; Bazar, Matthew A; Quinn, Michael J; LaFiandra, Emily May; Talent, Larry G

    2010-04-01

    The explosive, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine or high-melting explosive (HMX), has been found in soils in areas used for testing and training by the military. Many of these areas contain habitat for valued wildlife species. In an effort to better understand the environmental consequences from exposure, a reptilian (western fence lizard [Sceloporus occidentalis]), an amphibian (red-backed salamander [Plethodon cinereus]), and a mammalian species (rabbit [Oryctolagus cuniculus]) were exposed to HMX under controlled laboratory conditions. Lizards and rabbits were exposed to HMX by way of corn oil through gavage, and salamanders were exposed to HMX in soil. Two deaths occurred from acute oral exposures to lizards to 5000 mg HMX/kg BW. Histological and gross pathologic assessment suggested gut impaction as a possible cause of death. Salamanders exposed to concentrations of HMX in soil < or = 1970 mg HMX/kg soil for 10 days did not show adverse effects. Rabbits, however, showed neurologic effects manifested as hyperkinetic events with convulsions at > 24 h after oral exposures. An LD(50) for rabbits was calculated as 93 mg/kg (95% confidence interval 76-117). A subacute 14-day testing regime found a lowest observed effect level of 10 mg/kg-d and a no observed adverse effect level of 5 mg/kg-d based on hyperkinesia and seizure incidence, although changes suggesting functional hepatic alterations were also found. These data suggest that physiologic differences between species, particularly in gastrointestinal structure and function, can affect the absorption of HMX and hence lead to marked differences in toxicity from exposure to the same compound. PMID:20012743

  12. Toxicity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in three vertebrate species.

    PubMed

    Johnson, Mark S; McFarland, Craig A; Bazar, Matthew A; Quinn, Michael J; LaFiandra, Emily May; Talent, Larry G

    2010-04-01

    The explosive, octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine or high-melting explosive (HMX), has been found in soils in areas used for testing and training by the military. Many of these areas contain habitat for valued wildlife species. In an effort to better understand the environmental consequences from exposure, a reptilian (western fence lizard [Sceloporus occidentalis]), an amphibian (red-backed salamander [Plethodon cinereus]), and a mammalian species (rabbit [Oryctolagus cuniculus]) were exposed to HMX under controlled laboratory conditions. Lizards and rabbits were exposed to HMX by way of corn oil through gavage, and salamanders were exposed to HMX in soil. Two deaths occurred from acute oral exposures to lizards to 5000 mg HMX/kg BW. Histological and gross pathologic assessment suggested gut impaction as a possible cause of death. Salamanders exposed to concentrations of HMX in soil < or = 1970 mg HMX/kg soil for 10 days did not show adverse effects. Rabbits, however, showed neurologic effects manifested as hyperkinetic events with convulsions at > 24 h after oral exposures. An LD(50) for rabbits was calculated as 93 mg/kg (95% confidence interval 76-117). A subacute 14-day testing regime found a lowest observed effect level of 10 mg/kg-d and a no observed adverse effect level of 5 mg/kg-d based on hyperkinesia and seizure incidence, although changes suggesting functional hepatic alterations were also found. These data suggest that physiologic differences between species, particularly in gastrointestinal structure and function, can affect the absorption of HMX and hence lead to marked differences in toxicity from exposure to the same compound.

  13. Elevated root retention of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in coniferous trees.

    PubMed

    Schoenmuth, Bernd; Mueller, Jakob O; Scharnhorst, Tanja; Schenke, Detlef; Büttner, Carmen; Pestemer, Wilfried

    2014-03-01

    For decades, the explosive RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) has been used for military and industrial applications. Residues of RDX pollute soils in large areas globally and the persistence and high soil mobility of these residues can lead to leaching into groundwater. Dendroremediation, i.e. the long-term use of trees to clean up polluted soils, is gaining acceptance as a green and sustainable strategy. Although the coniferous tree species Norway spruce and Scots pine cover large areas of military land in Central Europe, the potential of any coniferous tree for dendroremediation of RDX is still unknown. In this study, uptake experiments with a (14)C-labelled RDX solution (30 mg L(-1)) revealed that RDX was predominantly retained in the roots of 6-year-old coniferous trees. Only 23 % (pine) to 34 % (spruce) of RDX equivalents (RDXeq) taken up by the roots were translocated to aboveground tree compartments. This finding contrasts with the high aerial accumulation of RDXeq (up to 95 %) in the mass balances of all other plant species. Belowground retention of RDXeq is relatively stable in fine root fractions, since water leaching from tissue homogenates was less than 5 %. However, remobilisation from milled coarse roots and tree stubs reached up to 53 %. Leaching from homogenised aerial tree material was found to reach 64 % for needles, 58 % for stems and twigs and 40 % for spring sprouts. Leaching of RDX by precipitation increases the risk for undesired re-entry into the soil. However, it also opens the opportunity for microbial mineralisation in the litter layer or in the rhizosphere of coniferous forests and offers a chance for repeated uptake of RDX by the tree roots. PMID:24281674

  14. Deimos: A featureless asteroid-like spectrum

    NASA Technical Reports Server (NTRS)

    Grundy, W. M.; Fink, Uwe

    1991-01-01

    High quality CCD spectra were obtained of Deimos from 0.5 to 1.0 micron at a spectral resolution of 15A at the time of the 1988 Mars opposition. The data acquisition and reduction methods allowed the quantitative prevention of scattered light from Mars contaminating the spectra. Solar analog stars BS560, BS2007, and BS8931 were observed the same night to allow removal of telluric absorptions. The ratio spectrum of Deimos has a red slope, increasing in reflectance by a factor of approx. 50 pct. over the one octave wavelength interval observed. Other than this slope, the spectrum is remarkably featureless. The absence of absorption bands in the spectrum of Deimos is in marked contrast with the spectra of Martian surface materials. No trace of the Fe(2+) charge transfer absorption band around 1 micron is observed, which rules out the presence of significant quantities of minerals such as the pyroxenes or olivine at the surface of Deimos. The featureless red spectrum of Deimos appears to be consistent with a surface composition of fine grained carbonaceous chondrite type material. An analysis is presented of the spectrum of Deimos which makes use of the Hapke scattering surface model.

  15. Structure in the nucleus of NGC 1068 at 10 microns

    NASA Technical Reports Server (NTRS)

    Tresch-Fienberg, R.; Fazio, G. G.; Gezari, D. Y.; Lamb, G. M.; Shu, P. K.; Hoffmann, W. F.; Mccreight, C. R.

    1987-01-01

    New 8-13 micron array camera images of the central kiloparsec of Seyfert 2 galaxy NGC 1068 resolve structure that is similar to that observed at visible and radio wavelengths. The images reveal an infrared source which is extended and asymmetric, with its long axis oriented at P.A. 33 deg. Maps of the spatial distribution of 8-13 micron color temperature and warm dust opacity are derived from the multiwavelength infrared images. The results suggest that there exist two pointlike luminosity sources in the central region of NGC 1068, with the brighter source at the nucleus and the fainter one some 100 pc to the northeast. This geometry strengthens the possibility that the 10 micron emission observed from grains in the nucleus is powered by a nonthermal source. In the context of earlier visible and radio studies, these results considerably strengthen the case for jet-induced star formation in NGC 1068.

  16. Structure in the nucleus of NGC 1068 at 10 microns

    NASA Technical Reports Server (NTRS)

    Tresch-Fienberg, R.; Fazio, G. G.; Gezari, D. Y.; Hoffmann, W. F.; Lamb, G. M.; Shu, P. K.; Mccreight, C. R.

    1987-01-01

    New 8 to 13 micron array camera images of the central kiloparsec of Seyfert 2 galaxy NGC 1068 resolve structure that is similar to that observed at visible and radio wavelengths. The images reveal an infrared source which is extended and asymmetric, with its long axis oriented at P.A. 33 deg. Maps of the spatial distribution of 8 to 13 micron color temperature and warm dust opacity are derived from the multiwavelength infrared images. The results suggest that there exist two pointlike luminosity sources in the central regions of NGC 1068, with the brighter source at the nucleus and the fainter one some 100 pc to the northeast. This geometry strengthens the possibility that the 10 micron emission observed from grains in the nucleus is powered by a nonthermal source. In the context of earlier visible and radio studies, these results considerably strengthen the case for jet induced star formation in NGC 1068.

  17. MSX Observations of the Eclipsed Moon at 4 Microns

    NASA Astrophysics Data System (ADS)

    Howard, J. W.; Little, S. J.; Murdock, T. L.

    1997-07-01

    The lunar eclipse of September 27, 1996 presented the opportunity to observe the 4 micron emission from the moon during totality. The Midcourse Space Experiment (MSX) satellite made observations three times during the totality phase of the eclipse. These observations in Bands B1 (4.22 - 4.36 microns) and B2 (4.24 - 4.45 microns) were used to construct images of the eclipsed moon. The images have been analyzed for temperature and location of thermal anomalies on the moon as well as for temperatures of extended maria and highland areas. Maps of the moon to illustrate the location and brightness of thermal anomalies first seen by Saari and Shorthill (1965) and temperature comparisons with microwave measurements of selected regions on the moon (Sandor and Clancy, 1995) will be made. References: Saari, J. M., and R. W. Shorthill, 1965, Nature, 205, p. 964. Sandor, Brad J., and R. Todd Clancy, 1995, Icarus, 115, p. 387.

  18. The Beauty and Limitations of 10 Micron Heterodyne Interferometry (ISI)

    NASA Technical Reports Server (NTRS)

    Danchi, William C.

    2003-01-01

    Until recently, heterodyne interferometry at 10 microns has been the only successful technique for stellar interferometry in the very difficult atmospheric window from 9-12 microns. For most of its operational lifetime the U.C. Berkeley Infrared Spatial Interferometer was a single-baseline two telescope (1.65 m aperture) system using CO2 lasers as local oscillators. This instrument was designed and constructed from 1983-1988, and first fringes were obtained at Mt. Wilson in June 1988. During the past few years, a third telescope was constructed and just recently the first closure phases were obtained at 11.15 microns. We discuss the history, physics and technology of heterodyne interferometry in the mid-infrared, and some key astronomical results that have come from this unique instrument.

  19. Photosynthesis 3.5 thousand million years ago.

    PubMed

    Olson, J M; Pierson, B K

    1986-01-01

    The recent discovery of stromatolites and microfossils in 3.5-Ga-old sedimentary rock formations is evidence for the existence of phototrophic prokaryotes at that time. Values of δ(13)C for sedimentary organic carbon strongly suggest autotrophic CO2 fixation, and the existence of large deposits of sedimentary sulfate is consistent with a photosynthesis dependent on reduced sulfur compounds for reducing power. The ancient photoautotrophs are though to have contained only one kind of reaction center with either chlorophyll a or bacteriochlorophyll a as primary electron donor and with one or more iron-sulfur centers as secondary electron acceptors. Light-harvesting pigments might have been chlorophyll a, bacteriochlorophyll a, or possibly bacteriochlorophyll c.A new proposal is made to explain how these organisms could have survived an intense UV flux at the earth's surface in the absence of an ozone layer. Photochemically produced ferric iron was abundant in sediments, and the UV-absorption of this ferric iron would have been sufficient to shield those organisms living below the watersediment interface.

  20. Thermal emission from Saturn's rings at 380 microns

    SciTech Connect

    Roellig, T.L.; Werner, M.W.; Becklin, E.E.

    1988-03-01

    Two different techniques have been used to derive the Saturn disk's ring brightness temperatures from 380-micron observations: (1) comparisons of these wide-beam observation disk-ring system results with those obtained for an earlier epoch, when the rings were edge-on, then differencing the two measurements to obtain a value for the rings' contribution; and (2) ring contribution resolution during scanning along the disk-ring plane, to yield a B-ring brightness temperature of 39 + or - 8 K at 380 microns. The results obtained indicate a gradual decrease of observed ring brightness temperature from the IR to the radio wavelength range. 24 references.

  1. Discovery of new 2 micron sources in Rho Ophiuchi

    NASA Technical Reports Server (NTRS)

    Barsony, M.; Carlstrom, J. E.; Burton, Michael G.; Russell, A. P. G.; Garden, R.

    1989-01-01

    A 144-sq-arcmin region of the Rho Oph star-forming cloud core was surveyed at 2.2 microns, complete to mK = 14. A total of 61 sources are detected, 26 of which have been previously reported, accounting for a total of 35 new sources with mK = 12-14. There is no turnover in the 2-micron luminosity function of the Rho Oph cloud core to a limiting sensitivity of mK = 14. Two of the newly discovered sources are binary companions to previously cataloged objects.

  2. 2.15 Micron Laser Welding Of Gallbladder Tissue

    NASA Astrophysics Data System (ADS)

    Treat, Michael R.; Oz, Mehmet C.; Popp, Howard W.

    1989-09-01

    Laser welding of biliary tissues would be a valuable technique in conventional and endoscopic surgery. Laser welding would allow the avoidance of potentially lithogenic suture material as a sequela to biliary tract surgery. Laser welding would be compatable from the surgical technical standpoint with fiberoptic endoscopic intrumentation. The 2.15 micron thulium-holmium-chromium laser offers tissue penetration on the order of a few hundred microns. We have hypothesized that this laser might be well suited to performing biliary tissue welding. We evaluated this laser in vitro using canine gallbladder tissue and we were able to achieve histologically satisfactory tissue fusion and immediate bursting strengths above physiologically encountered biliary pressures.

  3. Efficient CW diode-pumped Tm, Ho:YLF laser with tunability near 2.067 microns

    NASA Technical Reports Server (NTRS)

    Mcguckin, B. T.; Menzies, Robert T.

    1992-01-01

    A conversion efficiency of 42 percent and slope efficiency of approximately 60 percent relative to absorbed pump power are reported from a continuous wave diode-pumped Tm, Ho:YLF laser at 2 microns with output power of 84 mW at sub-ambient temperatures. The emission spectrum is etalon tunable over a range of 16/cm centered on 2.067 microns, with fine tuning capability of the transition frequency with crystal temperature at a measured rate of about -0.03/cm-K. The effective emission cross section is measured to be 5 x 10 exp -21 sq cm. These and other aspects of the laser performance are discussed in the context of calculated atmospheric absorption characteristics in this spectral region and potential use in remote sensing applications.

  4. Bioavailability of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) to the Praire Vole (Microtus ochrogaster).

    SciTech Connect

    Fellows, Robert J.; Driver, Crystal J.; Cataldo, Dominic A.; Harvey, Scott D.

    2006-07-01

    Estimating risk to wildlife requires that measures of exposure be equivalent to that of the laboratory studies from which toxic responses were observed. Exposure measures are often based on modeled estimates of uptake through the food web. These modeled estimates use largely untested assumptions that can lead to inaccurate, uncertain, and unreliable estimates of exposure. Recently, concerns have been raised over the potential bioavailability and biotransfer of munitions or energetics materials such as hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). RDX is more recalcitrant in the soil, may remain as the parent compound for extended periods of time, and is rapidly taken up by the roots of higher plants and partitioned predominantly into the above ground, herbivore-accessible tissues. This study assessed plant incorporated [14C]-RDX and plant derived [14C]-RDX-metabolites ingestion by a representative hindgut herbivore, the prairie vole (Microtus ochrogaster). The animals were fed the labeled chow (≤10 g/ day max) for five or seven days followed by a six or four day chase period with the control chow prior to final weighing and sacrifice. Animal excreta including feces, urine, and respired CO2 were collected and measured. Greater than 95% of all label presented to the voles was recovered in the summed excreta. Seventy-four percent of the label in the total excreta was found in the fecal non-absorbed bulk. This means that greater than 20% of the presented 14C-RDX and plant-derived 14C-RDX-metabolites were absorbed by the animal’s digestive tracts over the time course of the experiment and modified prior to release. These materials were either metabolized to 14CO2 (8 to 10% of the total label) or removed as nitrogenous waste through the kidneys (10 to 14%). The feeding regimes were followed by a rapid, 2 to 3 day, clearing of label from the bulk feces with the cessation of exposure. Both 14C-urine and 14CO2 excretion continued after the feces cleared indicating

  5. Thermal oxidation of 3-5 compound semiconductors

    NASA Astrophysics Data System (ADS)

    Monteironeto, Othon Derego

    1988-11-01

    Thermal oxidation of 3-5 compound semiconductors has been studied in the temperature range of 300 to 600 C. Two members of this class of materials, namely InP and GaAs, were the object of the experimental work carried out here. The main analytical tools used were transmission electron microscopy (TEM) and secondary ion mass spectroscopy (SIMS). TEM was employed to access microstructural changes and SIMS to access the composition redistribution that takes place as a consequence of the oxidation reaction. Below 400 C oxidation of both materials led to the formation of amorphous scales, which consisted of a mixture of gallium and arsenic oxides in the case of GaAs, and indium phosphate and oxide in the case of InP. The oxidation kinetics of InP was found to be slower than that of GaAs. In the high temperature regime, i.e., above 400 C, the oxidation of both materials resulted in crystalline products. Precipitation of the group 5 element at the scale/semiconductor interface took place during oxidation. At the GaAs/Ga2O3interface, As precipitates were formed with a truncated square pyramid shape bound by (111) sub GaAs planes. The precipitates found at the InPO4/InP interface were either a phosphorus rich phase or red phosphorus. Strong vaporization under the electron beam prohibited a more accurate determination. The morphology of those precipitates were very similar to the As ones in GaAs.

  6. Polar switching in trialkylbenzene-1,3,5-tricarboxamides.

    PubMed

    Fitié, Carel F C; Roelofs, W S Christian; Magusin, Pieter C M M; Wübbenhorst, Michael; Kemerink, Martijn; Sijbesma, Rint P

    2012-04-01

    The hydrogen-bonded hexagonal columnar LC (Col(hd)) phases formed by benzene-1,3,5-tricarboxamide (BTA) derivatives can be aligned uniformly by an electric field and display switching behavior with a high remnant polarization. The polar switching in three symmetrically substituted BTAs with alkyl chains varying in length between 6 and 18 carbon atoms (C6, C10, and C18) was investigated by electro-optical switching experiments, dielectric relaxation spectroscopy (DRS), and solid-state NMR. The goal was to characterize ferroelectric properties of BTA-based columnar LCs, which display a macroscopic axial dipole moment due to the head-to-tail stacking of hydrogen-bonded amides. The Col(hd) phase of all three BTAs can be aligned uniformly by a dc field ∼30 V/μm. Moreover, C10 and C18 display extrinsic polar switching characterized by a remnant polarization and coercive field of 1-2 μC/cm(2) and 20-30 V/μm, respectively. In the absence of an external field, the polarization is lost in 1-1000 s, depending on device details and temperature. DRS revealed a columnar glass transition in the low-temperature region of the LC phase related to collective vibrations in the hydrogen-bonded columns that freeze out below 41-54 °C. At higher temperatures, a relaxation process is present originating from the collective reorientation of amide groups along the column axis (inversion of the macrodipole). Matching activation energies suggest that the molecular mechanism underlying the polar switching and the R-processes is identical. These results illustrate that LC phases based on BTAs offer the unique possibility to integrate polarization with other functionalities in a single nanostructured material.

  7. An Upper Limit on the Finescale Anisotropy of the Cosmic Background Radiation at 800-MICRONS

    NASA Astrophysics Data System (ADS)

    Church, S. E.; Lasenby, A. N.; Hills, R. E.

    1993-04-01

    In some models of the early Universe, radiation is reprocessed into the submillimetre and far-infrared by high-redshift dust, without violating COBE limits on the CBR spectrum, but producing secondary anisotropies which should be detectable with ground-based submillimetre telescopes. We describe an attempt to measure these anisotropies at 800 microns using the JCMT. A careful analysis to reduce position-dependent systematics was carried out and we show that, for this experiment, chopping the telescope beam in azimuth rather than RA produces lower systematics. Bayesian likelihood analysis is then used to set an upper limit on CBR fluctuations of {DELTA} T/T <~ 1.46 X 10^-3^ on a coherence scale of 17 arcsec. Data from a similar set of observations made by Kreysa & Chini in 1988 with the IBM 30-m telescope at 1300 microns are reanalysed in the same way to enable a comparison to be made. The results are used to set limits on the generation of cosmic backgrounds from primeval dust.

  8. Azimuthally averaged radial S(sub 100 microns)/S(sub 60 microns) dust color temperatures in spiral galaxies

    NASA Technical Reports Server (NTRS)

    Devereux, Nick A.

    1994-01-01

    The IRAS S(sub 100 micron)/S(sub 60 micron) dust color temperature profiles are presented for two nearby spiral galaxies M 101 and M 81. The radial dust temperature profiles provided an important constraint on the origin of the far-infrared luminosity. The observed dust temperature is compared with that expected for diffuse interstellar dust heated by the general interstellar radiation field within each galaxy. The implications for the contribution of cirrus to the far-infrared luminosity of M 101 and M 81 are discussed.

  9. Release of Micronized Copper Particles from Pressure Treated Wood Products

    EPA Science Inventory

    Micronized copper pressure treated lumber (PTL) has recently been introduced to the consumer market as a replacement for ionized copper PTL. The presence of particulate rather than aqueous copper raises concerns about the exposure of humans as well as the environment to the parti...

  10. Biogeography of a human oral microbiome at the micron scale.

    PubMed

    Mark Welch, Jessica L; Rossetti, Blair J; Rieken, Christopher W; Dewhirst, Floyd E; Borisy, Gary G

    2016-02-01

    The spatial organization of complex natural microbiomes is critical to understanding the interactions of the individual taxa that comprise a community. Although the revolution in DNA sequencing has provided an abundance of genomic-level information, the biogeography of microbiomes is almost entirely uncharted at the micron scale. Using spectral imaging fluorescence in situ hybridization as guided by metagenomic sequence analysis, we have discovered a distinctive, multigenus consortium in the microbiome of supragingival dental plaque. The consortium consists of a radially arranged, nine-taxon structure organized around cells of filamentous corynebacteria. The consortium ranges in size from a few tens to a few hundreds of microns in radius and is spatially differentiated. Within the structure, individual taxa are localized at the micron scale in ways suggestive of their functional niche in the consortium. For example, anaerobic taxa tend to be in the interior, whereas facultative or obligate aerobes tend to be at the periphery of the consortium. Consumers and producers of certain metabolites, such as lactate, tend to be near each other. Based on our observations and the literature, we propose a model for plaque microbiome development and maintenance consistent with known metabolic, adherence, and environmental considerations. The consortium illustrates how complex structural organization can emerge from the micron-scale interactions of its constituent organisms. The understanding that plaque community organization is an emergent phenomenon offers a perspective that is general in nature and applicable to other microbiomes. PMID:26811460

  11. Biogeography of a human oral microbiome at the micron scale

    PubMed Central

    Mark Welch, Jessica L.; Rossetti, Blair J.; Rieken, Christopher W.; Dewhirst, Floyd E.; Borisy, Gary G.

    2016-01-01

    The spatial organization of complex natural microbiomes is critical to understanding the interactions of the individual taxa that comprise a community. Although the revolution in DNA sequencing has provided an abundance of genomic-level information, the biogeography of microbiomes is almost entirely uncharted at the micron scale. Using spectral imaging fluorescence in situ hybridization as guided by metagenomic sequence analysis, we have discovered a distinctive, multigenus consortium in the microbiome of supragingival dental plaque. The consortium consists of a radially arranged, nine-taxon structure organized around cells of filamentous corynebacteria. The consortium ranges in size from a few tens to a few hundreds of microns in radius and is spatially differentiated. Within the structure, individual taxa are localized at the micron scale in ways suggestive of their functional niche in the consortium. For example, anaerobic taxa tend to be in the interior, whereas facultative or obligate aerobes tend to be at the periphery of the consortium. Consumers and producers of certain metabolites, such as lactate, tend to be near each other. Based on our observations and the literature, we propose a model for plaque microbiome development and maintenance consistent with known metabolic, adherence, and environmental considerations. The consortium illustrates how complex structural organization can emerge from the micron-scale interactions of its constituent organisms. The understanding that plaque community organization is an emergent phenomenon offers a perspective that is general in nature and applicable to other microbiomes. PMID:26811460

  12. The 100 micron detector development program. [gallium doped germanium photoconductors

    NASA Technical Reports Server (NTRS)

    Moore, W. J.

    1976-01-01

    An effort to optimize gallium-doped germanium photoconductors (Ge:Ga) for use in space for sensitive detection of far infrared radiation in the 100 micron region is described as well as the development of cryogenic apparatus capable of calibrating detectors under low background conditions.

  13. Validar: A Testbed for Advanced 2-Micron Doppler Lidar

    NASA Technical Reports Server (NTRS)

    Koch, Grady J.; Petros, Mulugeta; Barnes, Bruce W.; Beyon, Jeffrey Y.; Amzajerdian, Farzin; Yu, Jirong; Kavaya, Michael J.; Singh, Upendra N.

    2004-01-01

    High-energy 2-microns lasers have been incorporated in a breadboard coherent Doppler lidar to test component technologies and explore applications for remote sensing of the atmosphere. Design of the lidar is presented including aspects in the laser transmitter, receiver, photodetector, and signal processing. Sample data is presented on wind profiling and CO2 concentration measurements.

  14. Five-micron pictures of Jupiter. [infrared and color photography

    NASA Technical Reports Server (NTRS)

    Westphal, J. A.; Matthews, K.; Terrile, R. J.

    1974-01-01

    Several hundred five-micron 'video' pictures of Jupiter, with 1-sec resolution, made during September, October, and December 1973 and compared with color photographs, are shown to exhibit direct, detailed correlations with the darker 'purple' features. Forty-four of these pictures were made just before the Pioneer-10 encounter.

  15. The NASA - Arc 10/20 micron camera

    NASA Technical Reports Server (NTRS)

    Roellig, T. L.; Cooper, R.; Deutsch, L. K.; Mccreight, C.; Mckelvey, M.; Pendleton, Y. J.; Witteborn, F. C.; Yuen, L.; Mcmahon, T.; Werner, M. W.

    1994-01-01

    A new infrared camera (AIR Camera) has been developed at NASA - Ames Research Center for observations from ground-based telescopes. The heart of the camera is a Hughes 58 x 62 pixel Arsenic-doped Silicon detector array that has the spectral sensitivity range to allow observations in both the 10 and 20 micron atmospheric windows.

  16. Variability of Jupiter's Five-Micron Hot Spot Inventory

    NASA Technical Reports Server (NTRS)

    Yanamandra-Fisher, Padma A.; Orton, G. S.; Wakefield, L.; Rogers, J. H.; Simon-Miller, A. A.; Boydstun, K.

    2012-01-01

    Global upheavals on Jupiter involve changes in the albedo of entire axisymmetric regions, lasting several years, with the last two occurring in 1989 and 2006. Against this backdrop of planetary-scale changes, discrete features such as the Great Red Spot (GRS), and other vortices exhibit changes on shorter spatial- and time-scales. We track the variability of the discrete equatorial 5-micron hot spots, semi-evenly spaced in longitude and confined to a narrow latitude band centered at 6.5degN (southern edge of the North Equatorial Belt, NEB), abundant in Voyager images. Tantalizingly similar patterns were observed in the visible (bright plumes and blue-gray regions), where reflectivity in the red is anti-correlated with 5-microns thermal radiance. Ortiz et al. (1998, GRL, 103) characterized the latitude and drift rates of the hot spots, including the descent of the Galileo probe at the southern edge of a 5-micron hot spot, as the superposition of equatorial Rossby waves, with phase speeds between 99 - 103m/s, relative to System III. We note that the high 5-micron radiances correlate well but not perfectly with high 8.57-micron radiances. Because the latter are modulated primarily by changes in the upper ammonia (NH3) ice cloud opacity, this correlation implies that changes in the ammonia ice cloud field may be responsible for the variability seen in the 5-m maps. During the NEB fade (2011 - early 2012), however, these otherwise ubiquitous features were absent, an atmospheric state not seen in decades. The ongoing NEB revival indicates nascent 5-m hot spots as early as April 2012, with corresponding visible dark spots. Their continuing growth through July 2012 indicates the possit.le re-establishment of Rossby waves. The South Equatorial Belt (SEB) and NEB revivals began similarly with an instability that developed into a major outbreak, and many similarities in the observed propagation of clear regions.

  17. Spectral Irradiance Calibration in the Infrared. Part 6; 3-35 microns Spectra of Three Southern Standard Stars

    NASA Technical Reports Server (NTRS)

    Cohen, Martin; Witteborn, Fred C.; Bregman, Jesse D.; Wooden, Diane H.; Salama, Alberto; Metcalfe, Leo

    1996-01-01

    We present three new absolutely calibrated continuous stellar spectra from 3 to 35 microns, constructed as far as possible from actual observed spectral fragments taken from the Kuiper Airborne Observatory (KAO), and the IRAS Low Resolution Spectrometer (LRS). These stars- alpha(sup 1) Cen, alpha TrA, and epsilon Car-augment our previous archive of complete absolutely calibrated spectra for northern K and M giants. All these spectra have a common calibration pedigree. The wavelength coverage is ideal for calibration of many existing and proposed ground-based, airborne, and satellite sensors. KAO and IRAS data in the 15-30 micron range suggest that the spectra of cool giants are close to Rayleigh-Jeans slopes. Our observations of alpha(sup 1) Cen, absolutely calibrated via our adopted Sirius model, indicate an angular diameter in very good agreement with values in the literature, demonstrating 'closure' of the set of spectra within our absolute framework. We compare our observed alpha(sup 1) Cen spectrum with a published grid of theoretical models from Kurucz, and adopt a plausible theoretical shape, that fits our spectrum, as a secondary reference spectrum in the southern sky.

  18. Adenosine 3':5'-cyclic monophosphate in higher plants: Isolation and characterization of adenosine 3':5'-cyclic monophosphate from Kalanchoe and Agave.

    PubMed

    Ashton, A R; Polya, G M

    1977-07-01

    1.3':5'-Cyclic AMP was extensively purified from Kalanchoe daigremontiana and Agave americana by neutral alumina and anion- and cation-exchange column chromatography. Inclusion of 3':5'-cyclic [8-3H]AMP from the point of tissue extraction permitted calculation of yields. The purification procedure removed contaminating material that was shown to interfere with the 3':5'-cyclic AMP estimation and characterization procedures. 2. The partially purified 3':5'-cyclic AMP was quantified by means of a radiochemical saturation assay using an ox heart 3':5'-cyclic AMP-binding protein and by an assay involving activation of a mammalian protein kinase. 3. The plant 3':5'-cyclic AMP co-migrated with 3':5'-cyclic [8-3H]AMP on cellulose chromatography, poly(ethyleneimine)-cellulose chromatography and silica-gel t.l.c. developed with several solvent systems. 4. The plant 3':5'-cyclic AMP was degraded by ox heart 3':5'-cyclic nucleotide phosphodiesterase at the same rates as authentic 3':5'-cyclic AMP. 1-Methyl-3-isobutylxanthine (1 mM), a specific inhibitor of the 3':5'-cyclic nucleotide phosphodieterase, completely inhibited such degradation. 5. The concentrations of 3':5'-cyclic AMP satisfying the above criteria in Kalanchoe and Agave were 2-6 and 1 pmol/g fresh wt. respectively. Possible bacterial contribution to these analyses was estimated to be less than 0.002pmol/g fresh wt. Evidence for the occurrence of 3':5'-cyclic AMP in plants is discussed.

  19. Spectral Irradiance Calibration in the Infrared. Part 4; 1.2 - 35 microns Spectra of Six Standard Stars

    NASA Technical Reports Server (NTRS)

    Cohen, Martin; Witteborn, Fred C.; Walker, Russell G.; Bregman, Jesse D.; Wooden, Diane H.

    1995-01-01

    We present five new absolutely calibrated continuous stellar spectra from 1.2 to 35 microns, constructed as far as possible from actual observed spectral fragments taken from the ground, the Kuiper Airborne Observatory (KAO), and the IRAS Low Resolution Spectrometer (LRS). These stars- beta Peg, alpha Boo, beta And, beta Gem, and alpha Hya-augment our already created complete absolutely calibrated spectrum for alpha Tau. All these spectra have a common calibration pedigree. The wavelength coverage is ideal for calibration of many existing and proposed ground-based, airborne, and satellite sensors.

  20. Fission Spectrum

    DOE R&D Accomplishments Database

    Bloch, F.; Staub, H.

    1943-08-18

    Measurements of the spectrum of the fission neutrons of 25 are described, in which the energy of the neutrons is determined from the ionization produced by individual hydrogen recoils. The slow neutrons producing fission are obtained by slowing down the fast neutrons from the Be-D reaction of the Stanford cyclotron. In order to distinguish between fission neutrons and the remaining fast cyclotron neutrons both the cyclotron current and the pusle amplifier are modulated. A hollow neutron container, in which slow neutrons have a lifetime of about 2 milliseconds, avoids the use of large distances. This method results in much higher intensities than the usual modulation arrangement. The results show a continuous distribution of neutrons with a rather wide maximum at about 0.8 MV falling off to half of its maximum value at 2.0 MV. The total number of netrons is determined by comparison with the number of fission fragments. The result seems to indicate that only about 30% of the neutrons have energies below .8 MV. Various tests are described which were performed in order to rule out modification of the spectrum by inelastic scattering. Decl. May 4, 1951

  1. 60 micron luminosity evolution of rich clusters of galaxies

    SciTech Connect

    Kelly, D.M.; Rieke, G.H. )

    1990-10-01

    The average 60-micron flux has been determined for a collection of optically selected galaxy clusters at redshifts ranging from 0.30 to 0.92. The result, 26 mJy per cluster, represents the faintest flux determination known of using the IRAS data base. The flux from this set of clusters has been compared to the 60-micron flux from a sample of nearby galaxy clusters. It is found that the far-infrared luminosity evolution in cluster galaxies can be no more than a factor of 1.7 from z = 0.4 to the present epoch. This upper limit is close to the evolution predicted for simple aging of the stellar populations. Additional processes such as mergers, cannibalism, or enhanced rates of starbursts appear to occur at a low enough level that they have little influence on the far-infrared emission from clusters over this redshift range. 38 refs.

  2. 60 micron luminosity evolution of rich clusters of galaxies

    NASA Technical Reports Server (NTRS)

    Kelly, Douglas M.; Rieke, George H.

    1990-01-01

    The average 60-micron flux has been determined for a collection of optically selected galaxy clusters at redshifts ranging from 0.30 to 0.92. The result, 26 mJy per cluster, represents the faintest flux determination known of using the IRAS data base. The flux from this set of clusters has been compared to the 60-micron flux from a sample of nearby galaxy clusters. It is found that the far-infrared luminosity evolution in cluster galaxies can be no more than a factor of 1.7 from z = 0.4 to the present epoch. This upper limit is close to the evolution predicted for simple aging of the stellar populations. Additional processes such as mergers, cannibalism, or enhanced rates of starbursts appear to occur at a low enough level that they have little influence on the far-infrared emission from clusters over this redshift range.

  3. FIRBACK: A Large Area 175 micron Survey with ISO

    NASA Astrophysics Data System (ADS)

    Lagache, Guilaine

    We have conducted a deep cosmological large area survey at 175 microns with the ISOPHOT instrument in several high latitude regions relatively free of cirrus contamination. The main, but striking, result of this survey is that number counts of sources above 100 mJy is larger by about an order of magnitude than the extrapolation of the nearby IRAS 60 microns population of infrared galaxies. Nevertheless, these counts are consistent with predictions of the source population responsible for the Cosmic Far InfraRed Background detected with COBE. The FIRBACK collaboration involves J. L. Puget, D. L. Clements, H. Dole, R. Gispert, W. T. Reach, F. R. Bouchet, C. Cesarsky, F. X. Desert, D. Elbaz, A. Franceschini, B. Guiderdoni, M. Harwit, D. Lemke, R. Laureijs and A. F. M Moorwood.

  4. Photometric variability of Charon at 2.2 microns

    NASA Technical Reports Server (NTRS)

    Bosh, A. S.; Young, L. A.; Elliot, J. L.; Hammel, H. B.; Baron, R. L.

    1992-01-01

    Pluto-Charon images obtained on each of four nights at 2.2, 1.2, and 1.7 microns are presently fitted by a two-source image model in which the position of Charon and the ratio of its signal to that of Pluto are free parameters. At 2.2 microns, Charon is fainter than Pluto by magnitudes which, when combined with Pluto-Charon system photometry, yield apparent magnitudes of 15.01 + or - 0.08 for Charon at 0.06 lightcurve phase and 15.46 + or - 0.05 at lightcurve phase 0.42. In view of these results, Charon is variable in this filter bypass due to geometric albedo changes as a function of longitude.

  5. Correlation of infrared reflectance ratios at 2.3 microns/1.6 micron and 1.1 micron/1.6 micron with delta O-18 values delineating fossil hydrothermal systems in the Idaho batholith

    NASA Technical Reports Server (NTRS)

    Gillespie, A. R.; Criss, R. E.

    1983-01-01

    Reflectance ratios from laboratory spectra and airborne multispectral images are found to be strongly correlated with delta O-18 values of granite rocks in the Idaho batholith. The correlation is largely a result of interactions between hot water and rock, which lowered the delta O-18 values of the rocks and produced secondary hydrous material. Maps of the ratio of reflectivities at 2.3 and 1.6 microns should delineate fossil hydrothermal systems and provide estimates of alteration intensity. However, hydrous minerals produced during deuteric alteration or weathering cannot be unambiguously distinguished in remotely sensed images from the products of propylitic alteration without the use of narrow-band scanners. The reflectivity at 1.6 micron is strongly correlated with rock density and may be useful in distinguishing rock types in granitic terranes.

  6. Sub-Micron Velocity Measurements near a Moving Contact Line

    NASA Astrophysics Data System (ADS)

    Zimmerman, Jeremiah; Weislogel, Mark M.; Tretheway, Derek C.

    2010-03-01

    The displacement of one fluid by an immiscible second fluid (i.e. dynamic wetting), governs many natural and technological processes. Despite extensive studies, understanding and modeling the displacement process remains one of the outstanding problems in fluid mechanics. In this work, we explore the physics of the moving contact line (the idealized line of intersection between two fluids and a solid) with micron resolution particle image velocimetry (μPIV), which enables sub-micron two-dimensional velocity measurements. The measured flow is generated by dynamic wetting in a glass microchannel. The microchannel is mounted on an automated microscope stage with precise velocity control allowing for the static placement of the contact line within the field of view. Full-field velocity measurements within 1 μm of the contact line were made in water/glycerol and fructose/glucose/water solutions. Preliminary results appear to show remarkable similarity to controversial theoretical predictions.

  7. Visualization study on sedimentation of micron iron oxide particles.

    PubMed

    Chen, Jin-Fang; Luo, Ye; Xu, Jun-Hui; Chen, Qi-Ming; Guo, Jia

    2006-09-15

    In this paper, a novel technique combined light-electronic microscopy and computer imaging trace was used for visualization of the sedimentation of micron iron oxide particles in a customized micro-reactor. Micron iron oxide particles were recovered from the cinder of sulfuric acid production by sedimentation separating and hydraulic rating. Effects of particle size, shape and surface roughness on the sedimentation velocity were investigated. For irregular-shape particles, the sedimentation velocity and the geometric parameters of the particles were measured by the imaging trace technique. A correction coefficient (c) was used to modify the Stokes equation. In this study, the relationship between the correction coefficient and the equivalent diameter (d(p)) was found to be linear: c=0.6272-0.0298d(p), for iron oxide particles with equivalent diameter 4-22 microm.

  8. Radiation Pressure Measurements on Micron-Size Individual Dust Grains

    NASA Technical Reports Server (NTRS)

    Abbas, M. M.; Craven, P. D.; Spann, J. F.; Witherow, W. K.; West, E. A.; Gallagher, D. L.; Adrian, M. L.; Fishman, G. J.; Tankosic, D.; LeClair, A.

    2003-01-01

    Measurements of electromagnetic radiation pressure have been made on individual silica (SiO2) particles levitated in an electrodynamic balance. These measurements were made by inserting single charged particles of known diameter in the 0.2- to 6.82-micron range and irradiating them from above with laser radiation focused to beam widths of approximately 175- 400 microns at ambient pressures particle due to the radiation force is balanced by the electrostatic force indicated by the compensating dc potential applied to the balance electrodes, providing a direct measure of the radiation force on the levitated particle. Theoretical calculations of the radiation pressure with a least-squares fit to the measured data yield the radiation pressure efficiencies of the particles, and comparisons with Mie scattering theory calculations provide the imaginary part of the refractive index of SiO2 and the corresponding extinction and scattering efficiencies.

  9. Rotationally-Resolved Infrared Spectroscopy of the νb{16} Band of 1,3,5-TRIOXANE

    NASA Astrophysics Data System (ADS)

    Gibson, Bradley M.; Koeppen, Nicole; McCall, Benjamin J.

    2015-06-01

    1,3,5-trioxane is the simplest cyclic form of polyoxymethylene (POM), a class of formaldehyde polymers that has been proposed as the origin of distributed formaldehyde formation in comet comae and a potential source of formaldehyde in prebiotic chemistry. Although claimed POM detections have since been proven to be inconclusive, laboratory simulations of cometary conditions have yielded trioxane and other POMs While the microwave spectrum of 1,3,5-trioxane has been studied extensively, 4-7.}, to date only one rotationally-resolved ro-vibrational spectrum has been published. Here, we present our studies of the νb{16} band of gas-phase trioxane centered at 1177 wn. Trioxane was entrained in a supersonic expansion of argon and characterized by continuous-wave cavity ringdown spectroscopy using an etalon-stabilized external-cavity quantum cascade laser. Rotationally resolved spectra were obtained with less than 15 MHz resolution. Cottin, H., Bénilan, Y., Gazeau, M-C., and Raulin, F. Origin of Cometary Extended Sources from Degradation of Refractory Organics on Grains: Polyoxymethylene as Formaldehyde Parent Molecule. Icarus 167 (2004), 397-416. Oka, T., Tsuchiya, K., Iwata, S., and Morino, Y. Microwave Spectrum of s-Trioxane. Bull. Chem. Soc. Jpn. 37 (1964), 4-7. Henninot, J-F., Bolvin, H., Demaison, J., and Lemoine, B. The Infrared Spectrum of Trioxane in a Supersonic Slit Jet. J. Mol. Spect. 152 (1992), 62-68. Gibson, B.M. and McCall, B.J., contribution TJ08, presented at the 69th International Symposium on Molecular Spectroscopy, Urbana, IL, USA, 2014.

  10. Mix-and-match lithography for half-micron technology

    NASA Astrophysics Data System (ADS)

    Flack, Warren W.; Dameron, David H.

    1991-08-01

    Half-micron lithography for a production environment is not considered realistic with currently available lithography tools. While optical steppers have high wafer throughputs, they do not have sufficient process latitude at half-micron geometries. In contrast, advanced technologies with sufficient capabilities for half-micron processing such as direct-write e-beam and x-ray lithography are extremely expensive and have low effective throughputs. A mix-and- match lithography approach can take advantage of the best features of both types of systems by sing an optical stepper for noncritical levels and an advanced lithography system for critical levels. In order to facilitate processing of a triple level metal half-micron CMOS technology, a mix-and-match scheme has been developed between a Hitachi HL-700 D e-beam direct write system and an Ultratech 1500 wide-field 1x stepper. The Hitachi is used to pattern an accurate zero or registration level. All critical levels are exposed on the Hitachi and aligned back to this zero level. The Ultratech is used to align all other process levels which do not have critical targets that are placed on subsequent process levels. The mix-and-match approach is discussed, and optical to e-beam as well as e-beam to optical alignment results from seven production lots are presented. The linear alignment error components X translation, Y translation, rotation and magnification are extracted and analyzed to determine their source. It was found that a simple adjustment improved the registration capabilities of these two lithography tools by reducing the X translation, Y translation and rotation standard deviations by a factor of two or more, while greatly reducing the magnification errors between the two tools.

  11. Two micron pore size MCP-based image intensifiers

    NASA Astrophysics Data System (ADS)

    Glesener, John; Estrera, Joseph

    2010-02-01

    Image intensifiers (I2) have many advantages as detectors. They offer single photon sensitivity in an imaging format, they're light in weight and analog I2 systems can operate for hours on a single AA battery. Their light output is such as to exploit the peak in color sensitivity of the human eye. Until recent developments in CMOS sensors, they also were one of the highest resolution sensors available. The closest all solid state solution, the Texas Instruments Impactron chip, comes in a 1 megapixel format. Depending on the level of integration, an Impactron based system can consume 20 to 40 watts in a system configuration. In further investing in I2 technology, L-3 EOS determined that increasing I2 resolution merited a high priority. Increased I2 resolution offers the system user two desirable options: 1) increased detection and identification ranges while maintaining field-of-view (FOV) or 2) increasing FOV while maintaining the original system resolution. One of the areas where an investment in resolution is being made is in the microchannel plate (MCP). Incorporation of a 2 micron MCP into an image tube has the potential of increasing the system resolution of currently fielded systems. Both inverting and non-inverting configurations are being evaluated. Inverting tubes are being characterized in night vision goggle (NVG) and sights. The non-inverting 2 micron tube is being characterized for high resolution I2CMOS camera applications. Preliminary measurements show an increase in the MTF over a standard 5 micron pore size, 6 micron pitch plate. Current results will be presented.

  12. Is H2O present on Io? The detection of a new strong band near 3590/cm (2.79 microns)

    NASA Astrophysics Data System (ADS)

    Salama, F.; Allamandola, L. J.; Sandford, S. A.; Bregman, J. D.; Witteborn, F. C.; Cruikshank, D. P.

    1994-02-01

    A strong absorption band at 3590 +/- 20/cm (2.790 +/- 0.015 microns) has been discovered in the spectrum of Io using the Kuiper Airborne Observatory (KAO). The 2nu1 + nu3 combination mode of solid SO2 falls at this position. Since SO2 is abundant on Io it must contribute to the new band. However, a band due to H2O was predicted near this frequency in Io's spectrum based on laboratory experiments of H2O:SO2 mixed Io ice analogs which were used to assign the two weak, variable features at 3370 and 3170/cm (2.97 and 3.15 microns) to trace amounts of H2O frozen in solid SO2 on Io. The new band probably originates from both SO2 and H2O. Unfortunately, the spectral resolution of the data is insufficient to settle the issue of whether there are two resolvable components.

  13. Scanning SQUID susceptometers with sub-micron spatial resolution

    NASA Astrophysics Data System (ADS)

    Kirtley, John R.; Paulius, Lisa; Rosenberg, Aaron J.; Palmstrom, Johanna C.; Holland, Connor M.; Spanton, Eric M.; Schiessl, Daniel; Jermain, Colin L.; Gibbons, Jonathan; Fung, Y.-K.-K.; Huber, Martin E.; Ralph, Daniel C.; Ketchen, Mark B.; Gibson, Gerald W.; Moler, Kathryn A.

    2016-09-01

    Superconducting QUantum Interference Device (SQUID) microscopy has excellent magnetic field sensitivity, but suffers from modest spatial resolution when compared with other scanning probes. This spatial resolution is determined by both the size of the field sensitive area and the spacing between this area and the sample surface. In this paper we describe scanning SQUID susceptometers that achieve sub-micron spatial resolution while retaining a white noise floor flux sensitivity of ≈2μΦ0/Hz1/2. This high spatial resolution is accomplished by deep sub-micron feature sizes, well shielded pickup loops fabricated using a planarized process, and a deep etch step that minimizes the spacing between the sample surface and the SQUID pickup loop. We describe the design, modeling, fabrication, and testing of these sensors. Although sub-micron spatial resolution has been achieved previously in scanning SQUID sensors, our sensors not only achieve high spatial resolution but also have integrated modulation coils for flux feedback, integrated field coils for susceptibility measurements, and batch processing. They are therefore a generally applicable tool for imaging sample magnetization, currents, and susceptibilities with higher spatial resolution than previous susceptometers.

  14. A model for the CI (609 micron) emission of Orion

    NASA Technical Reports Server (NTRS)

    Tielens, A. G. G. M.; Hollenbach, D.

    1985-01-01

    A numerical model energy balance and chemical equilibrium in the photodissociation regions at the edge of molecular clouds is presented. The model is used to calculate the emergent intensities of the following fine-structure lines: OI (at 63, 145 microns); CI (at 609, 370 microns); C II (at 158 microns); and the low-lying rotational transitions of CO. It is shown that column densities in the range 2 x 10 to the 17th to 2 x 10 to the 18th per sq cm can be obtained for the C(+)/C/CO transition region at the edges of molecular clouds. The difference in the column densities is attributed to changes in the charge exchange reactions of C(+) with SiO and S, and to the process of carbon self-healing. It is found that the calculations are in good agreement with the observed conditions in the photodissociation regions behind Orion (1) C Ori, and near the surface of OMC 1.

  15. Dissolution and pharmacokinetics of a novel micronized aspirin formulation.

    PubMed

    Voelker, M; Hammer, M

    2012-08-01

    Aspirin (acetylsalicylic acid, ASA) has been used as an analgesic, antipyretic and antiinflammatory drug for many years. A new 500 mg aspirin tablet formulation containing micronized active ingredient and an effervescent component has been developed for potential improvement in the onset of action for acute pain treatment. This paper describes the dissolution and the pharmacokinetics of the new formulation in comparison with regular aspirin tablets, aspirin granules and aspirin effervescent tablets. Micronized aspirin tablets dissolve significantly faster over a pH range from 1.2 to 6.8 compared to regular 500 mg aspirin tablets. Plasma concentration time curve comparison to regular 500 mg aspirin tablets showed a substantial improvement in the time to maximum plasma concentrations (T(max)) (ASA 17.5 min vs. 45 min) and an increase in maximum plasma concentration (C(max)) (ASA 13.8 μg/ml vs. 4.4 μg/ml) while the overall extent of exposure (AUC) remains almost unchanged. The data suggest a potential improvement for onset of action in treating acute pain with the new micronized aspirin formulation.

  16. Dissolution and pharmacokinetics of a novel micronized aspirin formulation.

    PubMed

    Voelker, M; Hammer, M

    2012-08-01

    Aspirin (acetylsalicylic acid, ASA) has been used as an analgesic, antipyretic and antiinflammatory drug for many years. A new 500 mg aspirin tablet formulation containing micronized active ingredient and an effervescent component has been developed for potential improvement in the onset of action for acute pain treatment. This paper describes the dissolution and the pharmacokinetics of the new formulation in comparison with regular aspirin tablets, aspirin granules and aspirin effervescent tablets. Micronized aspirin tablets dissolve significantly faster over a pH range from 1.2 to 6.8 compared to regular 500 mg aspirin tablets. Plasma concentration time curve comparison to regular 500 mg aspirin tablets showed a substantial improvement in the time to maximum plasma concentrations (T(max)) (ASA 17.5 min vs. 45 min) and an increase in maximum plasma concentration (C(max)) (ASA 13.8 μg/ml vs. 4.4 μg/ml) while the overall extent of exposure (AUC) remains almost unchanged. The data suggest a potential improvement for onset of action in treating acute pain with the new micronized aspirin formulation. PMID:22057729

  17. Measuring micron size beams in the SLC final focus

    SciTech Connect

    McCormick, D.; Ross, M.; DeBarger, S.

    1994-10-01

    A pair of high resolution wire scanners have been built and installed in the SLC final focus. The final focus optics uses a set of de-magnifying telescopes, and an ideal location for a beam size monitor is at one of the magnified image points of the interaction point. The image point chosen for these scanners is in the middle of a large bend magnet. The design beam spots here are about 2 microns in the vertical and 20 microns in the horizontal plane. The scanners presented a number of design challenges. In this paper we discuss the mechanical design of the scanner, and fabrication techniques of its ceramic wire support card which holds many 4 and 7 um carbon wires. Accurate motion of the wire during a scan is critical. In this paper we describe tests of stepper motors, gear combinations, and radiation hardened encoders needed to produce the required motion with a step resolution of 80 nanometers. Also presented here are the results of scattered radiation detector placement studies carried out to optimize the signal from the 4 micron wires. Finally, we present measurements from the scanner.

  18. Radiation Pressure Measurements on Micron Size Individual Dust Grains

    NASA Technical Reports Server (NTRS)

    Abbas, M. M.; Craven, P.D.; Spann, J. F.; Tankosic, D.; Witherow, W. K.; LeClair, A.; West, E.; Sheldon, R.; Gallagher, D. L.; Adrian, M. L.

    2003-01-01

    Measurements of electromagnetic radiation pressure have been made on individual silica (SiO2) particles levitated in an electrodynamic balance. These measurements were made by inserting single charged particles of known diameter in the 0.2 micron to 6.82 micron range and irradiating them from above with laser radiation focused to beam-widths of approx. 175-400 micron, at ambient pressures approx. 10(exp -3) to 10(exp -4) torr. The downward displacement of the particle due to the radiation force is balanced by the electrostatic force indicated by the compensating dc potential applied to the balance electrodes, providing a direct measure of the radiation force on the levitated particle. Theoretical calculations of the radiation pressure with a least-squares fit to the measured data yield the radiation pressure efficiencies of the particles, and comparisons with Mie scattering theory calculations provide the imaginary part of the refractive index of silica and the corresponding extinction and scattering efficiencies.

  19. The Intensities of Methane in the 3-5 μm Region Revisited

    NASA Astrophysics Data System (ADS)

    Féjard, L.; Champion, J. P.; Jouvard, J. M.; Brown, L. R.; Pine, A. S.

    2000-05-01

    The analysis of the linestrengths of the infrared spectrum of methane (12 and 13) in the 3-5 μm region has been revisited on the basis of new measurements from Fourier transform spectra recorded at Kitt Peak under various optical densities. A simultaneous fit of these new data with previously reported tunable difference-frequency laser data has been done. An effective transition moment model in tensorial form up to the third order of approximation within the Pentad scheme has been used. The standard deviations achieved are very close to the experimental precision: 3 and 1.5%, respectively, for the two sets of data for the 12CH4 molecule, representing a substantial improvement with respect to earlier studies. The integrated bandstrengths obtained in the present work differ from previously reported values by factors ranging from -5 to +6%. The correction for the ν3 band, the strongest band of the Pentad system, is +2% with respect to the study of Hilico et al. [J. C. Hilico, J. P. Champion, S. Toumi, V. G. Tyuterev, and S. A. Tashkun, J. Mol. Spectrosc. 168, 455-476 (1994)].

  20. 3',5'Di-O-trityluridine inhibits in vitro flavivirus replication.

    PubMed

    De Burghgraeve, Tine; Selisko, Barbara; Kaptein, Suzanne; Chatelain, Grégory; Leyssen, Pieter; Debing, Yannick; Jacobs, Michael; Van Aerschot, Arthur; Canard, Bruno; Neyts, Johan

    2013-05-01

    The dengue fever virus (DENV) and the yellow fever virus (YFV) are members of the genus flavivirus in the family Flaviviridae. An estimated 50-100 million cases of DENV infections occur each year and approximately half a million patients require hospitalization. There is no vaccine or effective antiviral treatment available. There is an urgent need for potent and safe inhibitors of DENV replication; ideally such compounds should have broad-spectrum activity against flaviviruses. We here report on the in vitro activity of 3',5'di-O-trityluridine on flavivirus replication. The compound results in a dose-dependent inhibition of (i) DENV- and YFV-induced cytopathic effect (CPE) (EC₅₀ values in the low micromolar range for the 4 DENV serotypes), (ii) RNA replication (DENV-2 EC₅₀=1.5 μM; YFV-17D EC₅₀=0.83 μM) and (iii) viral antigen production. Antiviral activity was also demonstrated in DENV subgenomic replicons (which do not encode the structural viral proteins) (EC₅₀=2.3 μM), indicating that the compound inhibits intracellular events of the viral replication cycle. Preliminary data indicate that the molecule may inhibit the viral RNA-dependent RNA polymerase. PMID:23470860

  1. Bench-Scale Testing of the Micronized Magnetite Process

    SciTech Connect

    Edward R. Torak; Peter J. Suardini

    1997-11-01

    A recent emphasis of the Department of Energy's (DOE's), Coal Preparation Program has been the development of high-efficiency technologies that offer near-term, low-cost improvements in the ability of coal preparation plants to address problems associated with coal fines. In 1992, three cost-shared contracts were awarded to industry, under the first High-Efficiency Preparation (HEP I) solicitation. All three projects involved bench-scale testing of various emerging technologies, at the Federal Energy Technology Center*s (FETC*s), Process Research Facility (PRF). The first HEP I project, completed in mid-1993, was conducted by Process Technology, Inc., with the objective of developing a computerized, on-line system for monitoring and controlling the operation of a column flotation circuit. The second HEP I project, completed in mid-1994, was conducted by a team led by Virginia Polytechnic Institute to test the Mozely Multi-Gravity Separator in combination with the Microcel Flotation Column, for improved removal of mineral matter and pyritic sulfur from fine coal. The last HEP I project, of which the findings are contained in this report, was conducted by Custom Coals Corporation to evaluate and advance a micronized-magnetite-based, fine-coal cycloning technology. The micronized-magnetite coal cleaning technology, also know as the Micro-Mag process, is based on widely used conventional dense-medium cyclone applications, in that it utilizes a finely ground magnetite/water suspension as a separating medium for cleaning fine coal, by density, in a cyclone. However, the micronized-magnetite cleaning technology differs from conventional systems in several ways: ! It utilizes significantly finer magnetite (about 5 to 10 micron mean particle size), as compared to normal mean particle sizes of 20 microns. ! It can effectively beneficiate coal particles down to 500M in size, as compared to the most advanced, existing conventional systems that are limited to a particle bottom

  2. GENE EXPRESSION CHANGES IN ARABIDOPSIS THALIANA SEEDLING ROOTS EXPOSED TO THE MUNITION HEXAHYDRO-1,3,5-TRINITRO-1,3,5-TRIAZINE

    EPA Science Inventory

    Arabidopsis thaliana root transcriptome responses to the munition, hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), were assessed using serial analysis of gene expression (SAGE). Comparison of the transcriptional profile for the RDX response to a profile previously described for Ar...

  3. Model Calculations of Solar Spectral Irradiance in the 3.7 Micron Band for Earth Remote Sensing Applications

    NASA Technical Reports Server (NTRS)

    Platnick, Steven; Fontenla, Juan M.

    2006-01-01

    Since the launch of the first Advanced Very High Resolution Radiometer (AVHRR) instrument aboard TIROS-N, measurements in the 3.7 micron atmospheric window have been exploited for use in cloud detection and screening, cloud thermodynamic phase and surface snow/ice discrimination, and quantitative cloud particle size retrievals. The utility of the band has led to the incorporation of similar channels on a number of existing satellite imagers and future operational imagers. Daytime observations in the band include both reflected solar and thermal emission energy. Since 3.7 micron channels are calibrated to a radiance scale (via onboard blackbodies), knowledge of the top-of-atmosphere solar irradiance in the spectral region is required to infer reflectance. Despite the ubiquity of 3.7 micron channels, absolute solar spectral irradiance data comes from either a single measurement campaign (Thekaekara et al. 1969) or synthetic spectra. In this study, we compare historical 3.7 micron band spectral irradiance data sets with the recent semi-empirical solar model of the quiet-Sun by Fontenla et al. (2006). The model has expected uncertainties of about 2 % in the 3.7 pm spectral region. We find that channel-averaged spectral irradiances using the observations reported by Thekaekara et al. are 3.2-4.1% greater than those derived from the Fontenla et al. model for MODIS and AVHRR instrument bandpasses; the Kurucz spectrum (1995) as included in the MODTRAN4 distribution, gives channel-averaged irradiances 1.2-1.5 % smaller than the Fontenla model. For the MODIS instrument, these solar irradiance uncertainties result in cloud microphysical retrievals uncertainties comparable with other fundamental reflectance error sources.

  4. 1H NMR for quantifying sulfide trapping efficiency by using 1,3,5-tris(2-hydroxyethyl)-1,3,5-triazinane.

    PubMed

    Canuto, André V S; Echevarria, Aurea

    2014-07-01

    Hydrogen sulfide (H2S) is an extremely toxic colourless gas; it is corrosive and denser than air. It usually happens in oil and natural gas fields, refineries, coal mines, and in some industrial effluent treatment systems. This work presents an alternative method of monitoring and quantifying H2S trapping efficiency by using 1,3,5-tris(2-hydroxyethyl)-1,3,5-triazinane as a sequestering agent, and sodium sulfide as a source of sulfide ion, through (1)H NMR spectroscopy. The results proved that the reaction occurs very quickly at 20 °C at pH 7 and 10. 3,5-di(2-hydroxyethyl)-1,3,5-thiodiazinane and 5-(2-hydroxyethyl)-1,3,5-dithiozinane were observed and quantified; it was evidenced that (1)H NMR spectroscopy can be applied as a fast and effective method to quantify H2S trapping efficiency. PMID:24723368

  5. Broadband 7 microns OPCPA pumped by a 2 microns picosecond Ho:YLF CPA system

    NASA Astrophysics Data System (ADS)

    Sanchez, Daniel; Hemmer, Michael; Baudisch, Matthias; Biegert, Jens; Chalus, Olivier; Simon-Boisson, Christophe; Zawilski, Kevin; Schunemann, Peter G.; Smirnov, Vadim; Hoogland, Heinar

    2016-03-01

    The development of coherent light sources with emission in the mid-IR is currently undergoing a remarkable revolution. The mid-IR spectral range has always been of tremendous interest, mainly to spectroscopists, due to the ability of mid-IR light to access rotational and vibrational resonances of molecules which give rise to superb sensitivity upon optical probing [1-3]. Previously, high energy resolution was achieved with narrowband lasers or parametric sources, but the advent of frequency comb sources has revolutionized spectroscopy by providing high energy resolution within the frequency comb structure of the spectrum and at the same time broadband coverage and short pulse duration [4-6]. Such carrier to envelope phase (CEP) controlled light waveforms, when achieved at ultrahigh intensity, give rise to extreme effects such as the generation of isolated attosecond pulses in the vacuum to extreme ultraviolet range (XUV) [7]. Motivated largely by the vast potential of attosecond science, the development of ultraintense few-cycle and CEP stable sources has intensified [8], and it was recognized that coherent soft X-ray radiation could be generated when driving high harmonic generation (HHG) with long wavelength sources [9-11]. Recently, based on this concept, the highest waveform controlled soft X-ray flux [12] and isolated attosecond pulse emission at 300 eV [13] was demonstrated via HHG from a 1850 nm, sub-2-cycle source [14]. Within strong field physics, long wavelength scaling may lead to further interesting physics such as the direct reshaping of the carrier field [15], scaling of quantum path dynamics [16], the breakdown of the dipole approximation [17] or direct laser acceleration [18]. The experimental development of long wavelength light sources therefore holds great promise in many fields of science and will lead to numerous applications beyond strong field physics and attosecond science. In this paper, we present the first mid-IR optical parametric

  6. Crystal growth, vibrational, optical, thermal and theoretical studies of a nonlinear optical material: 2-Methyl 3,5-dinitrobenzoic acid

    NASA Astrophysics Data System (ADS)

    Sangeetha, K.; Guru Prasad, L.; Mathammal, R.

    2016-11-01

    Single crystals of 2-methyl 3,5-dinitro benzoic acid with reasonable size have been grown by slow evaporation solution growth method using ethanol as solvent. Quantum chemical calculation of 2-methyl 3,5-Dinitro benzoic acid was carried out by using DFT/B3LYP/6-31+G(d,p) method. The powder X-ray diffraction pattern was recorded and indexed. Both the experimental and theoretical vibrational spectrum validates the presence of functional groups. Polarizability, first order hyperpolarizability and the electric dipole moment values have been computed theoretically. The 1H and 13C NMR chemical shift of the molecule was calculated and compared with experimental results. TG/DSC analysis has been employed to understand the thermal and physio-chemical stability of the title compound. Frequency conversion property of the crystal was tested by Kurtz and Perry method. Optical absorption behavior of the grown crystal was examined by recording the optical spectrum and band gap energy was also estimated. The calculated HOMO and LUMO energy shows the charge transfer nature of the molecule.

  7. Aromatic fluorine compounds. I. The synthesis of 2,5- and 3,5-difluorobenzotrifluorides

    USGS Publications Warehouse

    Finger, G.C.; Reed, F.H.

    1944-01-01

    The preparation of 2,5- and 3,5-difluorobenzotrifluoride and some of their intermediates is described. 3,5-Dinitrobenzotrifluoride was prepared from 3-nitrobenzotrifluoride with a fuming nitric-sulfuric acid mixture.

  8. Photon Counting Detectors for the 1.0 - 2.0 Micron Wavelength Range

    NASA Technical Reports Server (NTRS)

    Krainak, Michael A.

    2004-01-01

    We describe results on the development of greater than 200 micron diameter, single-element photon-counting detectors for the 1-2 micron wavelength range. The technical goals include quantum efficiency in the range 10-70%; detector diameter greater than 200 microns; dark count rate below 100 kilo counts-per-second (cps), and maximum count rate above 10 Mcps.

  9. Searching for the 3.5 keV Line in the Stacked Suzaku Observations of Galaxy Clusters

    NASA Astrophysics Data System (ADS)

    Bulbul, Esra; Markevitch, Maxim; Foster, Adam; Miller, Eric; Bautz, Mark; Loewenstein, Mike; Randall, Scott W.; Smith, Randall K.

    2016-11-01

    We perform a detailed study of the stacked Suzaku observations of 47 galaxy clusters, spanning a redshift range of 0.01–0.45, to search for the unidentified 3.5 keV line. This sample provides an independent test for the previously detected line. We detect a 2σ -significant spectral feature at 3.5 keV in the spectrum of the full sample. When the sample is divided into two subsamples (cool-core and non-cool core clusters), the cool-core subsample shows no statistically significant positive residuals at the line energy. A very weak (∼ 2σ confidence) spectral feature at 3.5 keV is permitted by the data from the non-cool-core clusters sample. The upper limit on a neutrino decay mixing angle of {\\sin }2(2θ )=6.1× {10}-11 from the full Suzaku sample is consistent with the previous detections in the stacked XMM-Newton sample of galaxy clusters (which had a higher statistical sensitivity to faint lines), M31, and Galactic center, at a 90% confidence level. However, the constraint from the present sample, which does not include the Perseus cluster, is in tension with previously reported line flux observed in the core of the Perseus cluster with XMM-Newton and Suzaku.

  10. 41 CFR 102-3.5 - What does this subpart cover and how does it apply?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 3 2010-07-01 2010-07-01 false What does this subpart cover and how does it apply? 102-3.5 Section 102-3.5 Public Contracts and Property Management Federal...? § 102-3.5 What does this subpart cover and how does it apply? This subpart provides the policy...

  11. 40 CFR 721.4265 - Hydrazinecarboxamide, N-(3,5-difluorophenyl-).

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 31 2011-07-01 2011-07-01 false Hydrazinecarboxamide, N-(3,5... Specific Chemical Substances § 721.4265 Hydrazinecarboxamide, N-(3,5-difluorophenyl-). (a) Chemical... hydrazinecarboxamide, N-(3,5-difluorophenyl-) (PMN P-97-649; CAS No. 167412-23-9) is subject to reporting under...

  12. 40 CFR 721.4265 - Hydrazinecarboxamide, N-(3,5-difluorophenyl-).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Hydrazinecarboxamide, N-(3,5... Specific Chemical Substances § 721.4265 Hydrazinecarboxamide, N-(3,5-difluorophenyl-). (a) Chemical... hydrazinecarboxamide, N-(3,5-difluorophenyl-) (PMN P-97-649; CAS No. 167412-23-9) is subject to reporting under...

  13. 41 CFR 102-3.5 - What does this subpart cover and how does it apply?

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 41 Public Contracts and Property Management 3 2012-01-01 2012-01-01 false What does this subpart cover and how does it apply? 102-3.5 Section 102-3.5 Public Contracts and Property Management Federal...? § 102-3.5 What does this subpart cover and how does it apply? This subpart provides the policy...

  14. 41 CFR 102-3.5 - What does this subpart cover and how does it apply?

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 41 Public Contracts and Property Management 3 2011-01-01 2011-01-01 false What does this subpart cover and how does it apply? 102-3.5 Section 102-3.5 Public Contracts and Property Management Federal...? § 102-3.5 What does this subpart cover and how does it apply? This subpart provides the policy...

  15. 41 CFR 102-3.5 - What does this subpart cover and how does it apply?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 3 2013-07-01 2013-07-01 false What does this subpart cover and how does it apply? 102-3.5 Section 102-3.5 Public Contracts and Property Management Federal...? § 102-3.5 What does this subpart cover and how does it apply? This subpart provides the policy...

  16. 41 CFR 102-3.5 - What does this subpart cover and how does it apply?

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 41 Public Contracts and Property Management 3 2014-01-01 2014-01-01 false What does this subpart cover and how does it apply? 102-3.5 Section 102-3.5 Public Contracts and Property Management Federal...? § 102-3.5 What does this subpart cover and how does it apply? This subpart provides the policy...

  17. The micron stroke hypothesis of Alzheimer's disease and dementia.

    PubMed

    Orehek, Allen J

    2012-05-01

    Alzheimer's disease as currently described in the medical literature is often more a description of dementia rather than a specific disease. In over a century of scientific work there has been no proven theory as to the precise pathogenesis of Alzheimer's disease and dementia. As there is no efficient treatment for patients with Alzheimer's disease, prevention or attenuation of the disease is of substantial value. An intricate collection of hypotheses, studies, research, and experience has made it complicated for one to completely understand this disease. The purpose of this hypothesis is to illustrate new concepts and work to link those concepts to the present understanding of an obscure disease. The search for a single unifying hypothesis on the etiology of Alzheimer's disease has been elusive. Many hypotheses associated to Alzheimer's disease have not survived their testing to become theory. Suggested here is that the elusive nature of etiology of dementia is not from one cause, but rather the causes are numerous. Medical terminology used freely for decades is rarely evaluated in the light of a new hypothesis. At the foundation of this work is the suggestion of a new medical term: Micron Strokes. The Micron Stroke Hypothesis of Alzheimer's Disease and Dementia include primary and secondary factors. The primary factors can be briefly described as baseline brain tissue, atrial fibrillation, hypercoaguable state, LDL, carotid artery stenosis, tobacco exposure, hypertension diabetes mellitus, and the presence of systemic inflammation. Dozens of secondary factors contribute to the development of dementia. Most dementia is caused by nine primary categories of factors as they interact to cause micron strokes to the brain.

  18. A High Energy 2-microns Laser for Multiple Lidar Applications

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Singh, Upendra N.; Barnes, James C.; Barnes, Norman P.; Petros, Mulugeta

    2000-01-01

    Solid-state 2-microns laser has been receiving considerable interest because of its eye-safe property and efficient diode pump operation, It has potential for multiple lidar applications to detect water vapor. carbon dioxide and winds. In this paper, we describe a 2-microns double pulsed Ho:Tm:YLF laser and end-pumped amplifier system. A comprehensive theoretical model has been developed to aid the design and optimization of the laser performance. In a single Q-switched pulse operation the residual energy stored in the Tm atoms will be wasted. However, in a double pulses operation mode, the residual energy stored in the Tm atoms will repopulate the Ho atoms that were depleted by the extraction of the first Q-switched pulse. Thus. the Tin sensitized Ho:YLF laser provides a unique advantage in applications that require double pulse operation, such as Differential Absorption Lidar (DIAL). A total output energy of 146 mJ per pulse pair under Q-switch operation is achieved with as high as 4.8% optical to optical efficiency. Compared to a single pulse laser, 70% higher laser efficiency is realized. To obtain high energy while maintaining the high beam quality, a master-oscillator-power-amplifier 2-microns system is designed. We developed an end-pumped Ho:Tm:YLF disk amplifier. This amplifier uses two diode arrays as pump source. A non-imaging lens duct is used to couple the radiation from the laser diode arrays to the laser disk. Preliminary result shows that the efficiency of this laser can be as high as 3%, a factor of three increases over side-pump configuration. This high energy, highly efficient and high beam quality laser is a promising candidate for use in an efficient, multiple lidar applications.

  19. The brightest high-latitude 12-micron IRAS sources

    NASA Technical Reports Server (NTRS)

    Hacking, P.; Beichman, C.; Chester, T.; Neugebauer, G.; Emerson, J.

    1985-01-01

    The Infrared Astronomical Satellite (IRAS) Point Source catalog was searched for sources brighter than 28 Jy (0 mag) at 12 microns with absolute galactic latitude greater than 30 deg excluding the Large Magellanic Cloud. The search resulted in 269 sources, two of which are the galaxies NGC 1068 and M82. The remaining 267 sources are identified with, or have infrared color indices consistent with late-type stars some of which show evidence of circumstellar dust shells. Seven sources are previously uncataloged stars. K and M stars without circumstellar dust shells, M stars with circumstellar dust shells, and carbon stars occupy well-defined regions of infrared color-color diagrams.

  20. A Two Micron Coherent Differential Absorption Lidar Development

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Petros, Mulugeta; Chen, Songsheng; Bai, Yingxin; Petzar, Paul J.; Trieu, Bo C.; Koch, Grady J.; Beyon, Jeffrey Y.; VanValkenburg, Randal L.; Kavaya, Michael J.; Singh, Upendra N.

    2010-01-01

    A pulsed, 2-micron coherent Differential Absorption Lidar (DIAL)/Integrated Path Differential Absorption (IPDA) transceiver, developed under the Laser Risk Reduction Program (LRRP) at NASA, is integrated into a fully functional lidar instrument. This instrument measures atmospheric CO2 profiles (by DIAL) from a ground platform. It allows the investigators to pursue subsequent in science-driven deployments, and provides a unique tool for Active Sensing of CO2 Emissions over Night, Days, and Seasons (ASCENDS) validation that was strongly advocated in the recent ASCENDS Workshop. Keywords: Differential Absorption Lidar, Near Infrared Laser,

  1. Extended 20 micron emission from the center of NGC 1068

    NASA Technical Reports Server (NTRS)

    Telesco, C. M.; Becklin, E. E.; Wynn-Williams, C. G.

    1980-01-01

    Multiaperture photometry of the Seyfert galaxy NGC 1068 is reported which demonstrates that significant 20 micron emission originates at positions located more than 3 arcsec, or 260 pc, from the nucleus. These observations strongly support arguments that most of the infrared flux is thermal emission from dust. It is argued that the dust giving rise to this extended emission cannot be heated solely by a compact nuclear object. It is suggested that there is a powerful energy-generation mechanism, possibly an enormous burst of star formation, operating on a scale much larger than that identified with the visible nucleus.

  2. Micron-scale lens array having diffracting structures

    DOEpatents

    Goldberg, Kenneth A

    2013-10-29

    A novel micron-scale lens, a microlens, is engineered to concentrate light efficiently onto an area of interest, such as a small, light-sensitive detector element in an integrated electronic device. Existing microlens designs imitate the form of large-scale lenses and are less effective at small sizes. The microlenses described herein have been designed to accommodate diffraction effects, which dominate the behavior of light at small length scales. Thus a new class of light-concentrating optical elements with much higher relative performance has been created. Furthermore, the new designs are much easier to fabricate than previous designs.

  3. Advanced composite applications for sub-micron biologically derived microstructures

    NASA Technical Reports Server (NTRS)

    Schnur, J. M.; Price, R. R.; Schoen, P. E.; Bonanventura, Joseph; Kirkpatrick, Douglas

    1991-01-01

    A major thrust of advanced material development is in the area of self-assembled ultra-fine particulate based composites (micro-composites). The application of biologically derived, self-assembled microstructures to form advanced composite materials is discussed. Hollow 0.5 micron diameter cylindrical shaped microcylinders self-assemble from diacetylenic lipids. These microstructures have a multiplicity of potential applications in the material sciences. Exploratory development is proceeding in application areas such as controlled release for drug delivery, wound repair, and biofouling as well as composites for electronic and magnetic applications, and high power microwave cathodes.

  4. Fabrication of Micron Scale Retroreflectors for Novel Biosensors

    NASA Astrophysics Data System (ADS)

    Sherlock, Tim

    Many bioanalytical and diagnostic methods detect the presence of secondary labels, such as colored particles, fluorescent molecules, nanoparticles, and enzyme reaction product, when they accumulate in the presence of the target biomolecules (i.e., bacteria, viruses, etc.) at predetermined locations. In this dissertation, we describe the development of a new class of labels consisting of micro-fabricated retroreflectors that are easy to image, compatible with machine vision automation, and can be detected in solution or within microfluidic channels. The retroreflecting structures are designed to return incident light directly back to its source over a large range of angles, making them extremely detectable using low cost, low numerical aperture objectives, as is evidenced by their common use as lane markers and in safety signs. This work describes two different biosensing systems using these labels. In the first, retroreflectors are fabricated at fixed locations at the base of microfluidic channels and their brightness is attenuated by the biologically-driven accumulation of magnetic particles, thus forming a readout strategy that well-suited for automation and multiplexing. The work demonstrates that single, micron-scale magnetic beads can be rapidly detected over very large areas (square millimeters). The second approach uses suspended corner cube retroreflectors, five microns on a side, as ultra bright labels that are bound to magnetic sample preparation beads in the presence of an analyte. The magnetic particles can then be moved to an imaging site within the sample where the cubes are readily detected. The fabrication of these micron-scale retroreflectors required the development of new lithography, thin film disposition, and reactive ion etching tools and the integration of chip-based structures with microfluidic systems. The dissertation also describes the experimental validation of a Fourier optics model that accounts for diffraction inherent to the micron

  5. WISE 3.4 micron Detection of PTF10acbp

    NASA Astrophysics Data System (ADS)

    Cutri, R. M.; Hoffman, D.; Masci, F.; Conrow, T.; Kasliwal, M. M.; Helou, G.; Ofek, E. O.; Kulkarni, S. R.; Surace, J.

    2011-01-01

    The Wide-field Infrared Survey Explorer (WISE; Wright et al. 2010 AJ 140, 1868) scanned the position of PTF10acbp (ATEL #3094), the luminous red nova in the spiral galaxy UGC 11973, 23 times between 2010 June 17 and June 23, and again 30 times between 2010 December 12 and December 16, just five days after the transient's discovery. The June observations were made during the WISE cryogenic survey yielding images at 3.4, 4.6, 12 and 22 microns.

  6. Spectrophotometry at 10 microns of T Tauri stars

    NASA Technical Reports Server (NTRS)

    Cohen, M.; Witteborn, F. C.

    1985-01-01

    New 8-13 micron spectra of 32 T Tau, or related young, stars are presented. Silicate emission features are commonly seen. Absorptions occur less frequently but also match the properties of silicate materials. The shape of the emission feature suggests that a more crystalline grain is responsible in the T Tau stars than those of the Trapezium region. The evolution of the silicate component of the circumstellar shell around T Tau stars, and its dependence upon stellar wind activity, visual linear polarization, and extinction are investigated. Several correlations suggest that the shells are likely to be flattened, disklike structures rather than spherical.

  7. Isolation of three hexahydro-1,3,5-trinitro-1,3,5-triazine-degrading species of the family Enterobacteriaceae from nitramine explosive-contaminated soil.

    PubMed Central

    Kitts, C L; Cunningham, D P; Unkefer, P J

    1994-01-01

    Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third isolate, identified as Citrobacter freundii, partially transformed RDX and generated high concentrations of nitroso-RDX intermediates. All three isolates produced 14CO2 from labeled RDX under O2-depleted culture conditions. While all three isolates transformed HMX, only M. morganii transformed HMX in the presence of RDX. PMID:7811097

  8. Isolation of three hexahydro-1,3,5-trinitro-1,3,5-triazine-degrading species of the family Enterobacteriaceae from nitramine explosive-contaminated soil.

    PubMed

    Kitts, C L; Cunningham, D P; Unkefer, P J

    1994-12-01

    Three species of the family Enterobacteriaceae that biochemically reduced hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) were isolated from nitramine explosive-contaminated soil. Two isolates, identified as Morganella morganii and Providencia rettgeri, completely transformed both RDX and the nitroso-RDX reduction intermediates. The third isolate, identified as Citrobacter freundii, partially transformed RDX and generated high concentrations of nitroso-RDX intermediates. All three isolates produced 14CO2 from labeled RDX under O2-depleted culture conditions. While all three isolates transformed HMX, only M. morganii transformed HMX in the presence of RDX.

  9. Role of nitrogen limitation in transformation of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) by Gordonia sp. strain KTR9.

    PubMed

    Indest, Karl J; Hancock, Dawn E; Jung, Carina M; Eberly, Jed O; Mohn, William W; Eltis, Lindsay D; Crocker, Fiona H

    2013-03-01

    The transcriptome of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine)-degrading strain Gordonia sp. strain KTR9 and its glnR mutant were studied as a function of nitrogen availability to further investigate the observed ammonium-mediated inhibition of RDX degradation. The results indicate that nitrogen availability is a major determinant of RDX degradation and xplA gene expression in KTR9.

  10. Search for Vega-like nearby stars with 12 micron excess

    NASA Technical Reports Server (NTRS)

    Aumann, Hartmut H.; Probst, Ronald G.

    1991-01-01

    The identification of Vega-like main-sequence stars with 10-micron excess would permit important measurements of the spatial extent of the radiating material with ground-based telescopes. In fact, 55 of the 548 nearby A, F, G, and K dwarfs with IRAS catalog magnitudes at 12 microns appear to have excess 12-micron flux. However, for only two of these stars, Beta Pic and Zeta Lep, was it possible, using small-aperture photometry at 2.2 and 10 microns, to verify that the 12-micron excess is with high likelihood associated with the star. For the remaining stars the apparent 12-micron color of the 106 A, F, G, and K stars in the observing program is only 0.02 mag. Excess flux due to a Vega-like cloud which may surround some of the sources in the observing program, like Alpha Lyrae, is thus typically not detectable at 10 microns.

  11. VTT's micron-scale silicon rib+strip waveguide platform

    NASA Astrophysics Data System (ADS)

    Aalto, Timo; Harjanne, Mikko; Cherchi, Matteo

    2016-05-01

    Silicon rib waveguides enable single-mode (SM) operation even with the combination of multi-micron core dimensions and high refractive index contrast. In such large waveguides the optical mode field is almost completely confined inside the Si core, which leads to small propagation losses and small polarization dependency. The unique SM condition of the rib waveguide also enables the use of an ultra-wide wavelength range, for example from 1.2 to <1.7 μm, without sacrificing either SM operation or low propagation loss. This makes micron-scale Si waveguides particularly well-suited for spectroscopy and extensive wavelength division multiplexing. However, rib waveguides require large bending radii, which lead to large circuit sizes. There are two solutions for this. So-called Euler bends in Si strip waveguides enable low-loss bends down to 1 μm bending radius with less than 0.1 dB/90° loss for both polarizations. Another alternative is a total-internal reflection mirror that can have loss as low as 0.1 dB for both polarizations in either strip or rib waveguides. The excitation of higher order modes in large strip waveguides is avoided by using adiabatic rib-strip converters and low-loss components. With rib and strip waveguides it is possible to reach a unique combination of low loss, extremely small footprint, small polarization dependency, ultra-wide bandwidth and tolerance to high optical powers.

  12. Chemically generated convective transport of micron sized particles

    NASA Astrophysics Data System (ADS)

    Shklyaev, Oleg; Das, Sambeeta; Altemose, Alicia; Shum, Henry; Balazs, Anna; Sen, Ayusman

    2015-11-01

    A variety of chemical and biological applications require manipulation of micron sized objects like cells, viruses, and large molecules. Increasing the size of particles up to a micron reduces performance of techniques based on diffusive transport. Directional transport of cargo toward detecting elements reduces the delivery time and improves performance of sensing devices. We demonstrate how chemical reactions can be used to organize fluid flows carrying particles toward the assigned destinations. Convection is driven by density variations caused by a chemical reaction occurring at a catalyst or enzyme-covered target site. If the reaction causes a reduction in fluid density, as in the case of catalytic decomposition of hydrogen peroxide, then fluid and suspended cargo is drawn toward the target along the bottom surface. The intensity of the fluid flow and the time of cargo delivery are controlled by the amount of reagent in the system. After the reagent has been consumed, the fluid pump stops and particles are found aggregated on and around the enzyme-coated patch. The pumps are reusable, being reactivated upon injection of additional reagent. The developed technique can be implemented in lab-on-a-chip devices for transportation of micro-scale object immersed in solution.

  13. Chip-on-flex with 5-micron features

    NASA Astrophysics Data System (ADS)

    Salmon, Peter C.

    2003-01-01

    A new module packaging method is proposed for electronic systems comprising a motherboard and integrated circuit (IC) chips. Pitches of 10 microns for conductive traces, and 100 microns for bonding pads are achievable. The enabling technology is glass panel manufacture, using equipment and techniques similar to those employed for fabricating liquid crystal display (LCD) panels. Flexible circuits are produced on a glass carrier using a release layer, and the carrier is removed after most of the processing is complete. IC chips are stud bumped and flip chip bonded to wells filled with solder, provided on the flexible circuit. The fabrication density achievable with wafer level packaging (WLP) using silicon wafers is substantially more than is needed for module packaging, as described herein. It is possible to provide WLP performance on glass at a much lower cost. The conductor features on glass are fine enough for the most demanding packaging and assembly techniques. The lowered cost of glass applies to the interconnection circuit plus assembly, test and rework. A test method called Tester-On-Board (TOB) is proposed, employing special-purpose test chips that are directly mounted in the system and mimic the capabilities of external testers. Methods for hermetic sealing, electromagnetic screening, and high-density off-board connections are also proposed.

  14. The micro fabrication using selective laser sintering micron metal powder

    NASA Astrophysics Data System (ADS)

    Chen, Jimin; Wang, Xubao; Zuo, Tiechuan

    2003-04-01

    Selective laser sintering (SLS) is a process that uses a rastering laser to sinter powder particles into a computer defined shape. In order to fabricate micro part with laser sintering the laser beam spot should be focused smaller, on the other hand the size of sintered powder particles should be smaller too. Therefore Nd:YAG laser doubling frequency is used to obtain mini-focus. Based on theories of nonlinear and resonant cavity, an equipment which perform frequency doubling on YAG laser(1.06μm) by the external resonant ring cavity has been designed. With the equipment the wave length of 0.532μm green light was output. The focused laser spot of 15μm diameter was obtained with 10W power. Meanwhile the micron metal powder was used in selective laser micro sintering (SLMS). The behavior of laser sintering different metal powder was investigated. Finally the micro Chinese characters which is small as a tip of match made with laser selective micro sintering micron metal powder are shown.

  15. Micron: an Actively Stabilized Handheld Tool for Microsurgery

    PubMed Central

    MacLachlan, Robert A.; Becker, Brian C.; Tabarés, Jaime Cuevas; Podnar, Gregg W.; Lobes, Louis A.; Riviere, Cameron N.

    2011-01-01

    We describe the design and performance of a hand-held actively stabilized tool to increase accuracy in micro-surgery or other precision manipulation. It removes involuntary motion such as tremor by actuating the tip to counteract the effect of the undesired handle motion. The key components are a three-degree-of-freedom piezoelectric manipulator that has 400 μm range of motion, 1 N force capability, and bandwidth over 100 Hz, and an optical position measurement subsystem that acquires the tool pose with 4 μm resolution at 2000 samples/s. A control system using these components attenuates hand motion by at least 15 dB (a fivefold reduction). By considering the effect of the frequency response of Micron on the human visual feedback loop, we have developed a filter that reduces unintentional motion, yet preserves intuitive eye-hand coordination. We evaluated the effectiveness of Micron by measuring the accuracy of the human/machine system in three simple manipulation tasks. Handheld testing by three eye surgeons and three non-surgeons showed a reduction in position error of between 32% and 52%, depending on the error metric. PMID:23028266

  16. Autism Spectrum Disorder

    MedlinePlus

    ... Awards Enhancing Diversity Find People About NINDS NINDS Autism Spectrum Disorder Information Page Condensed from Autism Spectrum ... en Español Additional resources from MedlinePlus What is Autism Spectrum Disorder? Autistic disorder (sometimes called autism or ...

  17. Characterization of Metabolites during Biodegradation of Hexahydro-1,3,5-Trinitro-1,3,5-Triazine (RDX) with Municipal Anaerobic Sludge†

    PubMed Central

    Hawari, Jalal; Halasz, Annamaria; Sheremata, Tamara; Beaudet, Sylvie; Groom, Carl; Paquet, Louise; Rhofir, Chakib; Ampleman, Guy; Thiboutot, Sonia

    2000-01-01

    The biodegradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in liquid cultures with municipal anaerobic sludge showed that at least two degradation routes were involved in the disappearance of the cyclic nitramine. In one route, RDX was reduced to give the familiar nitroso derivatives hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX) and hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine (DNX). In the second route, two novel metabolites, methylenedinitramine [(O2NNH)2CH2] and bis(hydroxymethyl)nitramine [(HOCH2)2NNO2], formed and were presumed to be ring cleavage products produced by enzymatic hydrolysis of the inner C—N bonds of RDX. None of the above metabolites accumulated in the system, and they disappeared to produce nitrous oxide (N2O) as a nitrogen-containing end product and formaldehyde (HCHO), methanol (MeOH), and formic acid (HCOOH) that in turn disappeared to produce CH4 and CO2 as carbon-containing end products. PMID:10831452

  18. Phosphatidylinositol 3,5-bisphosphate: regulation of cellular events in space and time.

    PubMed

    Jin, Natsuko; Lang, Michael J; Weisman, Lois S

    2016-02-01

    Phosphorylated phosphatidylinositol lipids are crucial for most eukaryotes and have diverse cellular functions. The low-abundance signalling lipid phosphatidylinositol 3,5-bisphosphate [PI(3,5)P2] is critical for cellular homoeostasis and adaptation to stimuli. A large complex of proteins that includes the lipid kinase Fab1-PIKfyve, dynamically regulates the levels of PI(3,5)P2. Deficiencies in PI(3,5)P2 are linked to some human diseases, especially those of the nervous system. Future studies will probably determine new, undiscovered regulatory roles of PI(3,5)P2, as well as uncover mechanistic insights into how PI(3,5)P2 contributes to normal human physiology.

  19. The 2-micron plasmid as a nonselectable, stable, high copy number yeast vector

    NASA Technical Reports Server (NTRS)

    Ludwig, D. L.; Bruschi, C. V.

    1991-01-01

    The endogenous 2-microns plasmid of Saccharomyces cerevisiae has been used extensively for the construction of yeast cloning and expression plasmids because it is a native yeast plasmid that is able to be maintained stably in cells at high copy number. Almost invariably, these plasmid constructs, containing some or all 2-microns sequences, exhibit copy number levels lower than 2-microns and are maintained stably only under selective conditions. We were interested in determining if there was a means by which 2-microns could be utilized for vector construction, without forfeiting either copy number or nonselective stability. We identified sites in the 2-microns plasmid that could be used for the insertion of genetic sequences without disrupting 2-microns coding elements and then assessed subsequent plasmid constructs for stability and copy number in vivo. We demonstrate the utility of a previously described 2-microns recombination chimera, pBH-2L, for the manipulation and transformation of 2-microns as a pure yeast plasmid vector. We show that the HpaI site near the STB element in the 2-microns plasmid can be utilized to clone yeast DNA of at least 3.9 kb with no loss of plasmid stability. Additionally, the copy number of these constructs is as high as levels reported for the endogenous 2-microns.

  20. Two Micron Laser Technology Advancements at NASA Langley Research Center

    NASA Technical Reports Server (NTRS)

    Singh, Upendra N.

    2010-01-01

    An Independent Laser Review Panel set up to examine NASA s space-based lidar missions and the technology readiness of lasers appropriate for space-based lidars indicated a critical need for an integrated research and development strategy to move laser transmitter technology from low technical readiness levels to the higher levels required for space missions. Based on the review, a multiyear Laser Risk Reduction Program (LRRP) was initiated by NASA in 2002 to develop technologies that ensure the successful development of the broad range of lidar missions envisioned by NASA. This presentation will provide an overview of the development of pulsed 2-micron solid-state laser technologies at NASA Langley Research Center for enabling space-based measurement of wind and carbon dioxide.

  1. Nature of the 1100 Micron AzTEC-COSMOS Sources

    NASA Astrophysics Data System (ADS)

    Yun, Min Su; Aguirre, J.; Aretxaga, I.; Austermann, J.; Bock, J.; Fazio, G.; Huang, J.; Hughes, D.; Kang, Y.; Kim, S.; Lowenthal, J.; Ma, C.; Mauskopf, P.; Perera, T.; Sanders, D.; Scott, K.; Scoville, N.; Wilson, G.; Yoon, I.

    2006-12-01

    The Cosmic Evolution Survey (COSMOS) is a 2 square degree HST/ACS survey specifically designed to probe galaxy evolution as a function of time and environment (PI: N. Scoville). To take advantage of the extensive complementary databases already available through the COSMOS collaboration, we have undertaken a 1100 micron imaging survey of a 30' x 30' field centered just north of the earlier mm/submm surveys by the Bolocam on CSO and MAMBO on the IRAM 30-m telescope. In this poster paper, we will compare the results of the AzTEC and Bolocam surveys and discuss the nature of the AzTEC sources based on the existing multi-wavelength data in hand.

  2. The 1.083 micron tunable CW semiconductor laser

    NASA Technical Reports Server (NTRS)

    Wang, C. S.; Chen, Jan-Shin; Lu, Ken-Gen; Ouyang, Keng

    1991-01-01

    A tunable CW laser is desired to produce light equivalent to the helium spectral line at 1.08 microns. This laser will serve as an optical pumping source for He-3 and He-4 atoms used in space magnetometers. This light source can be fabricated either as a semiconductor laser diode or a pumped solid state laser. Continuous output power of greater than 10 mW is desired. Semiconductor lasers can be thermally tuned, but must be capable of locking onto the helium resonance lines. Solid state lasers must have efficient pumping sources suitable for space configuration. Additional requirements are as follows: space magnetometer applications will include low mass (less than 0.5 kg), low power consumption (less than 0.75 W), and high stability/reliability for long missions (5-10 years).

  3. The 4 micron spectra of compact infrared sources

    NASA Technical Reports Server (NTRS)

    Hofmann, R.; Larson, H. P.; Fink, U.

    1986-01-01

    High resolution 5 arcsec spectra in the 4 micron region are presented of the central 5 arcsec of the compact near infrared sources K3-50, W51-IRS2 East, and G333.6-0.2. From measured Br-alpha/Pf-beta line ratios and previously published infrared and radio maps, it is concluded that standard recombination theory fails to explain our observations in at least two cases. It is demonstrated that the data are consistent with thermal excitation of the hydrogen lines in strong stellar winds. The Pf-beta Hu-epsilon line ratio, which is completely insensitive to differential extinction, confirms the need for the stellar wind model for the core of G333.6-0.2. From the (K III) line it is estimated that the potassium abundance in G333.6-0.2 is at least equal to the solar value, and possibly enhanced by a factor up to 10.

  4. EUV mask reflectivity measurements with micron-scale spatial resolution

    SciTech Connect

    Goldberg, Kenneth A.; Rekawa, S.B.; Kemp, C.D.; Barty, A.; Anderson, E.H.; Kearney, Patrick; Han, Hakseung

    2008-05-26

    The effort to produce defect-free mask blanks for EUV lithography relies on increasing the detection sensitivity of advanced mask inspection tools, operating at several wavelengths. We describe the unique measurement capabilities of a prototype actinic (EUV wavelength) microscope that is capable of detecting small defects and reflectivity changes that occur on the scale of microns to nanometers. Types of defects: (a) Buried Substrate Defects: particles & pits (causes amplitude and/or phase variations); (b) Surface Contamination (reduces reflectivity and (possibly) contrast); (c) Damage from Inspection and Use (reduces the reflectivity of the multilayer coating). This paper presents an overview of several topics where scanning actinic inspection makes a unique contribution to EUVL research. We describe the role of actinic scanning inspection in four cases: defect repair studies; observations of laser damage; after scanning electron microscopy; and native and programmed defects.

  5. Predicting fracture in micron-scale polycrystalline silicon MEMS structures.

    SciTech Connect

    Hazra, Siddharth S.; de Boer, Maarten Pieter; Boyce, Brad Lee; Ohlhausen, James Anthony; Foulk, James W., III; Reedy, Earl David, Jr.

    2010-09-01

    Designing reliable MEMS structures presents numerous challenges. Polycrystalline silicon fractures in a brittle manner with considerable variability in measured strength. Furthermore, it is not clear how to use a measured tensile strength distribution to predict the strength of a complex MEMS structure. To address such issues, two recently developed high throughput MEMS tensile test techniques have been used to measure strength distribution tails. The measured tensile strength distributions enable the definition of a threshold strength as well as an inferred maximum flaw size. The nature of strength-controlling flaws has been identified and sources of the observed variation in strength investigated. A double edge-notched specimen geometry was also tested to study the effect of a severe, micron-scale stress concentration on the measured strength distribution. Strength-based, Weibull-based, and fracture mechanics-based failure analyses were performed and compared with the experimental results.

  6. 8- to 13-micron spectroscopy of Comet Levy 1990 XX

    NASA Technical Reports Server (NTRS)

    Lynch, David K.; Russell, Ray W.; Hackwell, John A.; Hanner, Martha S.; Hammel, Heidi B.

    1992-01-01

    The results are reported of IR spectroscopy of Comet Levy 1990 XX over a three-day period when the comet was about 1.54 AU from the sun roughly 70 days before perihelion. Comet Levy 1990 XX was bright, and for at least part of its inbound journey toward perihelion, active. At a distance of 1.54 AU from the sun it showed strong structured silicate emission with peaks or shoulders at 9.8 and 11.2 microns. These features resemble those of Comets P/Halley and Bradfield 1987 XXIX. The comet was variable in brightness. Specifically, the contrast of the silicate features changed by a factor of two relative to the continuum level and showed some evidence for a shape change as well.

  7. High spatial resolution 10 micron imaging of IRC + 10216

    NASA Technical Reports Server (NTRS)

    Bloemhof, E. E.; Danchi, W. C.; Townes, C. H.; Mclaren, R. A.

    1988-01-01

    Precise high-resolution 10-micron images of the carbon star IRC + 10216 have been obtained with a scanned linear array. The low noise and high dynamic range of these images permit deconvolution of the telescope point-spread function, revealing the radial brightness distribution of the circumstellar dust shell: approximate reflection symmetry is found in west-east scans, with a distinct division into two components of diameter about 0.40 and 2.2 arcsec. It is shown that this morphology is consistent with published interferometric data that had cast doubt upon an earlier, idealized two-component model. The observed brightness distribution implies that the circumstellar dust density may deviate substantially from the 1/r squared radial dependence expected for spherically symmetric outflow with constant velocity and constant rate of mass loss.

  8. Mars Atmospheric Characterization Using Advanced 2-Micron Orbiting Lidar

    NASA Technical Reports Server (NTRS)

    Singh, U.; Engelund, W.; Refaat, T.; Kavaya, M.; Yu, J.; Petros, M.

    2015-01-01

    Mars atmospheric characterization is critical for exploring the planet. Future Mars missions require landing massive payloads to the surface with high accuracy. The accuracy of entry, descent and landing (EDL) of a payload is a major technical challenge for future Mars missions. Mars EDL depends on atmospheric conditions such as density, wind and dust as well as surface topography. A Mars orbiting 2-micron lidar system is presented in this paper. This advanced lidar is capable of measuring atmospheric pressure and temperature profiles using the most abundant atmospheric carbon dioxide (CO2) on Mars. In addition Martian winds and surface altimetry can be mapped, independent of background radiation or geographical location. This orbiting lidar is a valuable tool for developing EDL models for future Mars missions.

  9. Multiple-Instrument Analyses of Single Micron-Size Particles

    NASA Astrophysics Data System (ADS)

    Admon, Uri; Donohue, David; Aigner, Helmut; Tamborini, Gabriele; Bildstein, Olivier; Betti, Maria

    2005-08-01

    Physical, chemical, and isotopic analyses of individual radioactive and other particles in the micron-size range, key tools in environmental research and in nuclear forensics, require the ability to precisely relocate particles of interest (POIs) in the secondary ion mass spectrometer (SIMS) or in another instrument, after having been located, identified, and characterized in the scanning electron microscope (SEM). This article describes the implementation, testing, and evaluation of the triangulation POIs re-location method, based on microscopic reference marks imprinted on or attached to the sample holder, serving as an inherent coordinate system. In SEM-to-SEM and SEM-to-SIMS experiments re-location precision better than 10 [mu]m and 20 [mu]m, respectively, is readily attainable for instruments using standard specimen stages. The method is fast, easy to apply, and facilitates repeated analyses of individual particles in different instruments and laboratories.

  10. A doublet microlens array for imaging micron-sized objects

    PubMed Central

    Tripathi, A; Chronis, N

    2011-01-01

    We present a high-numerical aperture, doublet microlens array for imaging micron-sized objects. The proposed doublet architecture consists of glass microspheres trapped on a predefined array of silicon microholes and covered with a thin polymer layer. A standard silicon microfabrication process and a novel fluidic assembly technique were combined to obtain an array of 56 μm diameter microlenses with a numerical aperture of ~0.5. Using such an array, we demonstrated brightfield and fluorescent image formation of objects directly on a CCD sensor without the use of intermediate lenses. The proposed technology is a significant advancement toward the unmet need of inexpensive, miniaturized optical modules which can be further integrated with lab-on-chip microfluidic devices and photonic chips for a variety of high-end imaging/detection applications. PMID:22003271

  11. Nanoscale patterns on micron-sized bubbles in foams

    NASA Astrophysics Data System (ADS)

    Dressaire, Emilie; Bell, David; Bee, Rodney; Lips, Alex; Stone, Howard

    2006-11-01

    The rheology and coarsening of foams is closely related to the microstructural characteristics of the small gas bubbles and their surface properties. We present experimental results of a foam formed upon shearing a mixture composed of glucose syrup and sucrose ester. Transmission Electron Microscopy reveals micron-size bubbles whose surfaces are fully covered with regular nanodimension, generally hexagonal, patterns. The influence of the shear rate during foam generation and the setting time on the development of the nanoscale patterns on the gas microcells are described. Plausible routes, driven by disproportionation of the gas from the small bubbles, for the formation of the nanoscale patterns are considered including a nucleation/crystallization pathway (Kim et al. 2003 Langmuir 19, p. 8455) and the buckling of an elastic insoluble surface film.

  12. TIMMI, ESO's new 10 micron Camera/Spectrometer

    NASA Astrophysics Data System (ADS)

    Kaeufl, H. U.; Jouan, R.; Lagage, P. O.; Masse, P.; Mestreau, P.; Tarrius, A.

    TIMMI stands for Thermal Infrared Multi Mode Instrument. TIMMI allows for imaging (at present 16 filters available) with variable magnifications as well as limited long-slit spectroscopy in the 10micron atmospheric window. The instrument was built by the Service d'Astrophysique (SAP) according to ESO's specification in a period of two years. At the telescope the instrument is using the f35 chopping configuration in conjunction with the special adaptor unit. TIMMI control and primary data-acquisition is performed by an VME-based computer (under OS9) while final data storage and online data processing with ESO's image processing system MIDAS is done using an UNIX workstation. While TIMMI will provide new observational possibilities for the ESO users community it is also supposed to become a test-bed to gain experience for similar instrumentation at the VLT.

  13. Passive athermalization of doublets in 8-13 micron waveband

    NASA Astrophysics Data System (ADS)

    Schuster, Norbert

    2014-10-01

    Passive athermalization of lenses has become a key-technology for automotive and other outdoor applications using modern uncooled 25, 17 and 12 micron pixel pitch bolometer arrays. Typical pixel counts for thermal imaging are 384x288 (qVGA), 640x480 (VGA), and 1024x768 (XGA). Two lens arrangements (called Doublets) represent a cost effective way to satisfy resolution requirements of these detectors with F-numbers 1.4 or faster. Thermal drift of index of refraction and the geometrical changes (in lenses and housing) versus temperature defocus the initial image plane from the detector plane. The passive athermalization restricts this drop of spatial resolution in a wide temperature range (typically -40°C…+80°C) to an acceptable value without any additional external refocus. In particular, lenses with long focal lengths and high apertures claim athermalization. A careful choice of lens and housing materials and a sophistical dimensioning lead to three different principles of passivation: The Passive Mechanical Athermalization (PMA) shifts the complete lens cell, the Passive Optical and Mechanical Athermalization (POMA) shifts only one lens inside the housing, the Passive Optical Athermalization (POA) works without any mechanism. All three principles will be demonstrated for a typical narrow-field lens (HFOV about 12°) with high aperture (aperture based F-number 1.3) for the actual uncooled reference detector (17micron VGA). Six design examples using different combinations of lens materials show the impact on spatial lens resolution, on overall length, and on weight. First order relations are discussed. They give some hints for optimization solutions. Pros and cons of different passive athermalization principles are evaluated in regards of housing design, availability of materials and costing. Examples with a convergent GASIR®1-lens in front distinguish by best resolution, short overall length, and lowest weight.

  14. Mass Spectrometry of Atmospheric Aerosol: 1 nanometer to 1 micron

    NASA Astrophysics Data System (ADS)

    Worsnop, D. R.; Ehn, M.; Junninen, H.; Kulmala, M. T.

    2010-12-01

    The role of aerosol particles remains the largest uncertainty in quantitatively assessing past, current and future climate change. The principal reason for that uncertainty arises from the need to characterize and model composition and size dependent aerosol processes, ranging from nanometer to micron scales. Aerosol mass spectrometry results have shown that about half the sub-micron aerosol composition is composed of highly oxygenated organics that are not well understood in terms of photochemical reaction mechanisms (Jimenez et al, 2009). This work has included application of high resolution time-of-flight mass spectrometry (ToFMS) in order to determine elemental and functional group composition of complex organic components. Recently, we have applied similar ToFMS to determine the composition of ambient ions, molecules and clusters, potentially involved in formation and growth of nano-particles (Junninen et al, 2010). Observed organic anions (molecular weight range 200-500 Th) have similar chemical composition as the least volatile secondary organics observed in fine particles; while organic cations are dominated by amines and pyridines. During nucleation events, anions are dominated by sulphuric acid cluster ions (Ehn et al, 2010). In both nanometer and micrometer size ranges, the goal to elucidate the roles of inorganic and organic species, particularly how particle evolution and physical properties depend on mixed compositions. Recent results will be discussed, including ambient and experimental chamber observations. Ehn et al, Atmos. Chem. Phys. Discuss., 10, 14897-14946, 2010 Jimenez et al, Science, 326, 1525-1529, 2009 Junninen et al, Atmos. Meas. Tech., 3, 1039-1053, 2010

  15. Ab initio studies of 1,3,5,7-tetranitro-1,3,5,7-tetrazocine/1,3-dimethyl-2-imidazolidinone cocrystal under high pressure using dispersion corrected density functional theory

    SciTech Connect

    Gu, Bang-Ming; Lin, He; Zhu, Shun-Guan

    2014-04-14

    A detailed study of structural, electronic, and thermodynamic properties of 1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)/1,3-dimethyl-2-imidazolidinone (DMI) cocrystal under the hydrostatic pressure of 0–100 GPa was performed by using dispersion-corrected density functional theory (DFT-D) method. The calculated crystal structure is in reasonable agreement with the experimental data at the ambient pressure. Based on the analysis of lattice constants, bond lengths, bond angles, and dihedral angles under compression, it is found that HMX molecules in HMX/DMI cocrystal are seriously distorted. In addition, as the pressure increases, the band gap decreases gradually, which suggests that HMX/DMI cocrystal is becoming more metallic. Some important intermolecular interactions between HMX and DMI are also observed in the density of states spectrum. Finally, its thermodynamic properties were characterized, and the results show that HMX/DMI cocrystal is more easily formed in the low pressure.

  16. The first salen-type ligands derived from 3',5'-diamino-3',5'-dideoxythymidine and -dideoxyxylothymidine and their corresponding copper(II) complexes

    PubMed Central

    Koth, Daniel; Gottschaldt, Michael; Görls, Helmar; Pohle, Karolin

    2006-01-01

    Background There are many nucleoside metal complexes known. According to observations made, only very few of them reveal their central ion to be co-ordinated by the sugar part of their molecules. The regio- and stereospecific exchange of the hydroxyl groups at the sugar moiety by chelating units improves its complexation ability and should give access to a new class of chiral ligands. Results In this paper we present the synthesis of 3',5'-diamino substituted thymidines with ribo- as well as xylo-configuration and the preparation of copper(II) complexes derived from their corresponding Schiff bases. Starting from thymidine, the amino derivatives were prepared in a three and four step reaction sequence respectively. The absolute configuration of the ligands was proved by the three-bond 1H-1H spin spin coupling constants 3J obtained by NMR-studies. Condensation of the amino derivatives with salicylic aldehydes resulted in the corresponding diimines, which represent a new class of chiral salen-type ligands. All ligands formed uncharged stable copper(II) complexes. The structure of 3',5'-bis(3,5-di-tert-butylsalicylaldiminato)-3',5'-dideoxyxylothymidine-copper(II) could be determined by single crystal X-ray structure analysis. The copper centre in this complex has distorted tetrahedral coordination geometry. Conclusion For the synthesis of 3',5'-diamino-3',5'-dideoxy thymidines with xylo- as well as ribo-configuration an effective synthesis pathway has been developed. Their corresponding salicylidene imines form stable coordination compounds with copper(II) ions. They represent the first salen type complexes of nucleosides with this substitution pattern. PMID:16934149

  17. TIMS 1.6 micron Measurement of Atmospheric CO2 and CH4

    NASA Astrophysics Data System (ADS)

    Rairden, R. L.; Kumer, J. B.; Roche, A. E.; Palmer, A.

    2013-12-01

    The Tropospheric Infrared Mapping Spectrometers (TIMS) were originally developed with support from the NASA ESTO Instrument Incubator program (IIP). These were designed to operate in the spectral regions of the CO overtone and fundamental bands at about 2.33 and 4.67 microns, respectively. In the IIP it was shown these could provide measurements of CO vertical structure, with area coverage rate and spatial resolution that would satisfy GEO-CAPE requirements as laid out in the NRC Decadal Survey report. Since completion of the IIP there has been further internally supported development discussed by Kumer et al, Aerospace Conference, 2013 IEEE. In this presentation we describe a demonstration of TIMS capability in a third wavelength region with two orders operating from approximately 1602 to 1616 nm, and from 1646 to 1660 nm. We will discuss and illustrate the reversible conversion of the 2.33 TIMS for operation at 1600 - 1660 nm; the high quality of the spectral mages and excellent agreement with models; and automated calibration algorithms. The figures show a wavelength calibrated spectral image and excellent agreement of the data and model on a spectrum extracted from the image. Fig 1. Wavelength-calibrated image of sunlight through atmosphere, with methane lines. Yellow box outlines the rows averaged for profile. Fig 2. Calibrated spectral profile, data fit to modeled atmosphere H2O, CO2, and CH4.

  18. Detection of H3+ auroral emission in Jupiter's 5-micron window

    NASA Astrophysics Data System (ADS)

    Giles, R. S.; Fletcher, L. N.; Irwin, P. G. J.; Melin, H.; Stallard, T. S.

    2016-05-01

    We use high-resolution ground-based observations from the VLT CRIRES instrument in November 2012 to identify sixteen previously undetected H3+ emission lines from Jupiter's ionosphere. These emission lines are located in Jupiter's 5-micron window (4.5-5.2 μm), an optically-thin region of the planet's spectrum where the radiation mostly originates from the deep troposphere. The H3+ emission lines are so strong that they are visible even against this bright background. We measure the Doppler broadening of the H3+ emission lines in order to evaluate the kinetic temperature of the molecules, and we obtain a value of 1390 ± 160 K. We also measure the relative intensities of lines in the ν2 fundamental in order to calculate the rotational temperature, obtaining a value of 960 ± 40 K. Finally, we use the detection of an emission line from the 2ν2(2)-ν2 overtone to measure a vibrational temperature of 925 ± 25 K. We use these three independent temperature estimates to discuss the thermodynamic equilibrium of Jupiter's ionosphere.

  19. Wave number spectra from temperature-humidity infrared radiometer 6.7-micron water vapor data

    NASA Technical Reports Server (NTRS)

    Manney, Gloria L.; Stanford, John L.

    1990-01-01

    Wave number spectra from Nimbus 7 temperature-humidity infrared radiometer 6.7-micron water vapor data are analyzed using series 4800 km long, in regions free of high clouds and frontal zones. In these regions, the brightness temperatures approximate temperatures on a water vapor isosteric (constant density) surface, rather than averages over a broad vertical layer. Power above the noise can be extracted down to wavelengths of about 60 km. Fitting the power spectrum versus horizontal wave number k to a k to the -nth power law for wavelengths from 60 to a few hundred kilometers gives slopes of n = 2.7 to 3.0, depending on the exact wave numbers that are fitted. Thunderstorms and convective cloud systems may constitute an energy source for the reverse energy cascade which produces a -5/3 spectral slope. The results suggest that when these features are not present, the enstrophy-cascading process that gives a -3 slope may govern the motion at scales smaller than it has heretofore been observed.

  20. Generation of a quasi-monoergetic proton beam from laser-irradiated sub-micron droplets

    SciTech Connect

    Ter-Avetisyan, S.; Ramakrishna, B.; Prasad, R.; Borghesi, M.; Nickles, P. V.; Steinke, S.; Schnuerer, M.; Popov, K. I.; Ramunno, L.; Zmitrenko, N. V.; Bychenkov, V. Yu.

    2012-07-15

    Proton bursts with a narrow spectrum at an energy of (2.8 {+-} 0.3 MeV) are accelerated from sub-micron water spray droplets irradiated by high-intensity ({approx}5 Multiplication-Sign 10{sup 19} W/cm{sup 2}), high-contrast ({approx}10{sup 10}), ultra-short (40 fs) laser pulses. The acceleration is preferentially in the laser propagation direction. The explosion dynamics is governed by a residual ps-scale laser pulse pedestal which 'mildly' preheats the droplet and changes its density profile before the arrival of the high intensity laser pulse peak. As a result, the energetic electrons extracted from the modified target by the high-intensity part of the laser pulse establish an anisotropic electrostatic field which results in anisotropic Coulomb explosion and proton acceleration predominantly in the forward direction. Hydrodynamic simulations of the target pre-expansion and 3D particle-in-cell simulations of the measured energy and anisotropy of the proton emission have confirmed the proposed acceleration scenario.

  1. X-ray diffraction, spectroscopic and DFT studies of 1-(4-bromophenyl)-3,5-diphenylformazan

    SciTech Connect

    Tezcan, H.; Tokay, N.; Alpaslan, G.; Erdönmez, A.

    2013-12-15

    The crystal structure of 1-(4-bromophenyl)-3,5-diphenylformazan was determined by X-ray single crystal diffraction technique. The crystals are orthorhombic, a = 23.0788(9), b = 7.9606(3), c = 18.6340(12) Å, Z = 8, sp. gr. Pbca, R{sub 1} = 0.074. The structure was also examined using the density-functional theory. Its structure stability, and frontier molecular orbital components were discussed and the results were compared with X-ray and spectral results. The maximum absorbtion peaks of the UV-vis spectrum of the compound have been calculated using the time-dependent density-functional theory. It was found a good agreement between the calculated and experimental maximum absorption wavelength.

  2. Growth, structural, optical, thermal and laser damage threshold studies of an organic single crystal: 1,3,5 - triphenylbenzene (TPB)

    NASA Astrophysics Data System (ADS)

    Raja, R. Subramaniyan; Babu, G. Anandha; Ramasamy, P.

    2016-05-01

    Good quality single crystals of pure hydrocarbon 1,3,5-Triphenylbenzene (TPB) have been successfully grown using toluene as a solvent using controlled slow cooling solution growth technique. TPB crystallizes in orthorhombic structure with the space group Pna21. The structural perfection of the grown crystal has been analysed by high resolution X-ray diffraction measurements. The range and percentage of the optical transmission are ascertained by recording the UV-vis spectrum. Thermo gravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study its thermal properties. Powder second harmonic generation studies were carried out to explore its NLO properties. Laser damage threshold value has been determined using Nd:YAG laser operating at 1064 nm.

  3. Synthesis, Spectral Characterization and Fluorescent Assessment of 1,3,5-Triaryl-2-pyrazoline Derivatives: Experimental and Theoretical Studies.

    PubMed

    Ibrahim, Mohammad M; Al-Refai, Mahmoud; Ayub, Khurshid; Ali, Basem F

    2016-07-01

    Two new pyrazoline derivatives, namely 5-(4-bromophenyl)-3-(5-chlorothiophen-2-yl)-1-phenyl-4,5-dihydro-1H-pyrazole (3) and 5-(4-bromophenyl)-3-(2,5-dichlorothiophen-3-yl)-1-phenyl-4,5-dihydro-1H-pyrazole (4) have been synthesized and characterized based on their spectral (IR, (1)H and (13)C NMR and MS) data and microanalysis. The fluorescence properties of 3 and 4 were studied by UV-Vis and emission spectroscopy. For compound 3, a fluorescence emission was observed in the blue region of the visible spectrum. The effect of different solvents on fluorescence was also investigated. Density Functional Theory calculations have also been performed to gain insight into geometric, electronic and spectroscopic properties of the pyrazoline derivatives. Both structures are analysed and compared in order to rationalize the different behaviour in 3 and 4. PMID:27220512

  4. Biotransformation of the explosives 2,4,6-trinitrotoluene and 1,3,5-triaza 1,3,5-trinitrocyclohexane by Clostridium bifermentans

    SciTech Connect

    Regan, K.M.; Crawford, R.L.

    1994-12-31

    A strain of Clostridium bifermentans isolated from a munitions-supplemented enrichment was able to remove both TNT (2,4,6-trinitrotoluene) and RDX (1,3,5-triaza 1,3,5-trinitrocyclohexane) from its growth media. Biotransformations of TNT and RDX by cometabolism in a nutrient rich medium reduced the removal time from several days to a few hours, as compared to a nutrient limited medium. Redox potential (Eh) of the media had important effects on the biological and abiological transformations of the munition compounds.

  5. Cathodoluminescence Spectrum Imaging Software

    2011-04-07

    The software developed for spectrum imaging is applied to the analysis of the spectrum series generated by our cathodoluminescence instrumentation. This software provides advanced processing capabilities s such: reconstruction of photon intensity (resolved in energy) and photon energy maps, extraction of the spectrum from selected areas, quantitative imaging mode, pixel-to-pixel correlation spectrum line scans, ASCII, output, filling routines, drift correction, etc.

  6. Coherent laser radar at 2 microns using solid-state lasers

    NASA Technical Reports Server (NTRS)

    Henderson, Sammy W.; Suni, Paul J. M.; Hale, Charley P.; Hannon, Stephen M.; Magee, James R.; Bruns, Dale L.; Yuen, Eric H.

    1993-01-01

    Coherent laser radar systems using 2-micron Tm- and Tm, Ho-doped solid-state lasers are useful for the remote range-resolved measurement of atmospheric winds, aerosol backscatter, and DIAL measurements of atmospheric water vapor and CO2 concentrations. Recent measurements made with a 2-micron coherent laser radar system, advances in the laser technology, and atmospheric propagation effects on 2-micron coherent lidar performance are described.

  7. Method of refining 2,2-isopropylidenebis-3,5- dibromophenylene-4-oxydiethanol

    NASA Technical Reports Server (NTRS)

    Kobayashi, T.; Nawata, K.; Hiratsuka, K.

    1982-01-01

    A method of refining 2,2-isopropylidenebis-3,5-dibromophenylene-4-oxydiethanol is described which is characterized by recrystallization of 2,2-isopropylidenebis-3,5-dibromophenylene-4-oxydiethanol using one or more aromatic hydrocarbons such as benzene, xylene, toluene, ethylbenzene or pseudocumene.

  8. AquaSMART: Water & Boating Safety, Grades 3-5. Teacher's Guide.

    ERIC Educational Resources Information Center

    Texas State Dept. of Parks and Wildlife, Austin.

    This teacher's guide accompanies a program designed to teach water and boating safety to students in grades 3-5. The written curriculum accompanies a video, AquaSMART 3-5. The theme of the curriculum is AquaSMART. To become AquaSMART, students must learn 10 basic lessons for water and boating safety. The written curriculum begins with an overview…

  9. 45 CFR 3.5 - Lost and found, and abandoned property.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... Section 3.5 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE General § 3.5 Lost and found, and... Services Administration regulations (41 CFR part 101-48). Abandoned, or other unclaimed property and,...

  10. 45 CFR 3.5 - Lost and found, and abandoned property.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Section 3.5 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION CONDUCT OF PERSONS AND TRAFFIC ON THE NATIONAL INSTITUTES OF HEALTH FEDERAL ENCLAVE General § 3.5 Lost and found, and... Services Administration regulations (41 CFR part 101-48). Abandoned, or other unclaimed property and,...

  11. IMMUNOASSAY METHODS FOR MEASURING ATRAZINE AND 3,5,6-TRICHLORO-2-PYRIDINOL IN FOODS

    EPA Science Inventory

    This chapter describes the use of enzyme-linked immunosorbent assay (ELISA) methods for the analysis of two potential environmental contaminants in food sample media, atrazine and 3,5,6-trichloro-2-pyridinol (3,5,6-TCP). Two different immunoassay formats are employed: a magnetic...

  12. 14 CFR 3.5 - Statements about products, parts, appliances and materials.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., appliances and materials. 3.5 Section 3.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and materials. (a) Definitions. The following terms will have the stated meanings when used in this.... Product means an aircraft, aircraft engine, or aircraft propeller. Record means any writing, drawing,...

  13. 14 CFR 3.5 - Statements about products, parts, appliances and materials.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ..., appliances and materials. 3.5 Section 3.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and materials. (a) Definitions. The following terms will have the stated meanings when used in this.... Product means an aircraft, aircraft engine, or aircraft propeller. Record means any writing, drawing,...

  14. 14 CFR 3.5 - Statements about products, parts, appliances and materials.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., appliances and materials. 3.5 Section 3.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and materials. (a) Definitions. The following terms will have the stated meanings when used in this.... Product means an aircraft, aircraft engine, or aircraft propeller. Record means any writing, drawing,...

  15. 14 CFR 3.5 - Statements about products, parts, appliances and materials.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., appliances and materials. 3.5 Section 3.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and materials. (a) Definitions. The following terms will have the stated meanings when used in this.... Product means an aircraft, aircraft engine, or aircraft propeller. Record means any writing, drawing,...

  16. 14 CFR 3.5 - Statements about products, parts, appliances and materials.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., appliances and materials. 3.5 Section 3.5 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT... and materials. (a) Definitions. The following terms will have the stated meanings when used in this.... Product means an aircraft, aircraft engine, or aircraft propeller. Record means any writing, drawing,...

  17. Effect of experimental contamination with the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine on soil bacterial communities.

    PubMed

    Juck, D; Driscoll, B T; Charles, T C; Greer, C W

    2003-03-01

    The effect of contamination with the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) on an indigenous soil bacterial community was examined in two uncontaminated loam soil columns possessing native grasses. One column was spiked twice with RDX crystals for a total RDX load of 1000 mg (kg soil)(-1). The reduced metabolite of RDX degradation, hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine, was observed in the column leachate, suggesting anaerobic degradation of RDX. Denaturing gradient gel electrophoresis of PCR-amplified 16S rDNA from both contaminated and uncontaminated columns produced identical banding patterns which were stable over the course of the experimental period. The bacterial diversity remained high in the contaminated column, as determined by restriction fragment length polymorphism and rarefaction analyses of random 16S rDNA clones. These combined results suggested that long-term exposure to 1000 mg RDX (kg soil)(-1) did not produce an observable effect on bacterial diversity or the numerically dominant members of the indigenous soil bacterial community.

  18. Evaluation of micron size carbon fibers released from burning graphite composites

    NASA Technical Reports Server (NTRS)

    Sussholz, B.

    1980-01-01

    Quantitative estimates were developed of micron carbon fibers released during the burning of graphite composites. Evidence was found of fibrillated particles which were the predominant source of the micron fiber data obtained from large pool fire tests. The fibrillation phenomena were attributed to fiber oxidation effects caused by the fire environment. Analysis of propane burn test records indicated that wind sources can cause considerable carbon fiber oxidation. Criteria estimates were determined for the number of micron carbon fibers released during an aircraft accident. An extreme case analysis indicated that the upper limit of the micron carbon fiber concentration level was only about half the permissible asbestos ceiling concentration level.

  19. Spatial variations of the 3-micron emission features within Orion's Bar

    NASA Technical Reports Server (NTRS)

    Moorhouse, A.; Brand, P. W. J. L.; Geballe, T. R.; Allamandola, L. J.; Tielens, A. G. G. M.

    1988-01-01

    3-micron spectra of the Orion Bar region have been obtained at three positions corresponding to different distances from the exciting source. The recently discovered unidentified features at 3.46, 3.51, and 3.57 microns are clearly visible. The spectra show that the 3.4 and 3.51-micron emission features increase in intensity relative to the strong 3.3-micron feature as the distance from the exciting source increases. The implications for polycyclic aromatic hydrocarbons and recent ideas concerning their ultraviolet excitation and spatial evolution are discussed.

  20. Airborne spectrophotometry of P/Halley from 16 to 30 microns

    NASA Technical Reports Server (NTRS)

    Herter, T.; Gull, G. E.; Campins, H.

    1986-01-01

    Comet Halley was observed in the 16 to 30 micron region using the Cornell University 7-channel spectrometer (resolution = 0.02) on board the Kuiper Airborne Observatory on 1985 Dec. 14.2. A 30-arcsec aperture (FWHM) was used. Measurements centered on the nuclear condensation micron indicate that if present, the 20 micron silicate feature is very weak, and that a relatively narrow strong feature centered at 28.4 microns possibly exists. However, this feature may be an artifact of incomplete correction for telluric water vapor absorption.

  1. Hypocrellin B graft on activated carbon and photocatalytic oxidation of 2,3,5-trimethylphenol

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Li, Ying; Zhang, Pei; Zhang, Jucheng; Min, Yong; Yi, Zhongzhou; Zhang, Canbang; Wu, Mingzhu; Chen, Rui

    2008-12-01

    Hypocrellin B, a photosensitizer isolated from Hypocrella Bambuase sacc in Yunnan province, has significant anti-tumor and anti-virus character. In this article, hypocrellin B, which was grafted on activated carbon, was used as photocatalysts to catalytic oxidize 2,3,5-trimethylphenol to 2,3,5-trimethylhydrobenzoquinone because of its high photons efficiency. This study realized nearly 100% selectivity for 2,3,5-trimethylhydrobenzoquinone under visible light irradiation (>400nm) at aerobic atmosphere. The photocatalytic oxidation process has been studied by different parameters like the pretreatment of activated carbon, synthetic mehtod of grafted hypocrellin, and photo-assisted oxidation catalysis of 2,3,5-trimethylphenol to 2,3,5-trimethylhdrobenzoquinone. Compared to the conventional methods, this process could be more eco-friendly.

  2. Selection of quasi-monodisperse super-micron aerosol particles

    NASA Astrophysics Data System (ADS)

    Rösch, Michael; Pfeifer, Sascha; Wiedensohler, Alfred; Stratmann, Frank

    2014-05-01

    Size-segregated quasi monodisperse particles are essential for e.g. fundamental research concerning cloud microphysical processes. Commonly a DMA (Differential Mobility Analyzer) is used to produce quasi-monodisperse submicron particles. Thereto first, polydisperse aerosol particles are bipolarly charged by a neutralizer, and then selected according to their electrical mobility with the DMA [Knutson et al. 1975]. Selecting a certain electrical mobility with a DMA results in a particle size distribution, which contains singly charged particles as well as undesired multiply charged larger particles. Often these larger particles need to either be removed from the generated aerosol or their signals have to be corrected for in the data inversion and interpretation process. This problem becomes even more serious when considering super-micron particles. Here we will present two different techniques for generating quasi-monodisperse super-micron aerosol particles with no or only an insignificant number of larger sized particles being present. First, we use a combination of a cyclone with adjustable aerodynamic cut-off diameter and our custom-built Maxi-DMA [Raddatz et al. 2013]. The cyclone removes particles larger than the desired ones prior to mobility selection with the DMA. This results in a reduction of the number of multiply charged particles of up to 99.8%. Second, we utilize a new combination of cyclone and PCVI (Pumped Counterflow Virtual Impactor), which is based on purely inertial separation and avoids particle charging. The PCVI instrument was previously described by Boulter et al. (2006) and Kulkarni et al. (2011). With our two setups we are able to produce quasi-monodisperse aerosol particles in the diameter range from 0.5 to 4.4 µm without a significant number of larger undesired particles being present. Acknowledgements: This work was done within the framework of the DFG funded Ice Nucleation research UnIT (INUIT, FOR 1525) under WE 4722/1-1. References

  3. Clustering of the Diffuse Infrared Light from the COBE DIRBE Maps. 3; Power Spectrum Analysis and Excess Isotropic Component of Fluctuations

    NASA Technical Reports Server (NTRS)

    Kashlinsky, A.; Mather, J. C.; Odenwald, S.

    1999-01-01

    The cosmic infrared background (CIB) radiation is the cosmic repository for energy release throughout the history of the universe. The spatial fluctuations of the CIB resulting from galaxy clustering are expected to be at least a few percent on scales of a degree, depending on the luminosity and clustering history of the early universe. Using the all-sky data from the COBE DIRBE instrument at wavelengths 1.25 - 100 microns we attempt to measure the CIB fluctuations. In the near-IR, foreground emission is dominated by small scale structure due to stars in the Galaxy. There we find a strong correlation between the amplitude of the fluctuations and Galactic latitude after removing bright foreground stars. Using data outside the Galactic plane (absolute value of b > 20 deg) and away from the center (90 deg < l < 270 deg) we extrapolate the amplitude of the fluctuations to cosec absolute value of b = 0. We find a positive intercept of delta.F(sub rms) = 15.5(sup +3.7, sub -7.0), 5.9(sup +1.6, sub -3.7), 2.4(sup +0.5, sub -0.9), 2.0(sup +0.25, sub -0.5) nW/sq m.sr at 1.25, 2.2, 3.5 and 4.9 microns respectively, where the errors are the range of 92% confidence limits. For color subtracted maps between band 1 and 2 we find the isotropic part of the fluctuations at 7.6(sup +1.2, sub -2.4) nW/sq m.sr. Based on detailed numerical and analytic models, this residual is not likely to originate from the Galaxy, our clipping algorithm, or instrumental noise. We demonstrate that the residuals from the fit used in the extrapolation are distributed isotropically and suggest that this extra variance may result from structure in the CIB. We also obtain a positive intercept from a linear combination of maps at 1.25 and 2.2 microns. For 2 deg < theta < 15 deg, a power-spectrum analysis yields limits of (theta/5 deg) x delta.F(sub rms)(theta) < 6, 2.5, 0.8, 0.5 nW/sq m.sr at 1.25, 2.2, 3.5 and 4.9 microns respectively. From 10 - 100 microns, the dominant foregrounds are emission by dust

  4. Anisotropic modulus stabilisation: strings at LHC scales with micron-sized extra dimensions

    NASA Astrophysics Data System (ADS)

    Cicoli, M.; Burgess, C. P.; Quevedo, F.

    2011-10-01

    We construct flux-stabilised Type IIB string compactifications whose extra dimensions have very different sizes, and use these to describe several types of vacua with a TeV string scale. Because we can access regimes where two dimensions are hierarchically larger than the other four, we find examples where two dimensions are micron-sized while the other four are at the weak scale in addition to more standard examples with all six extra dimensions equally large. Besides providing ultraviolet completeness, the phenomenology of these models is richer than vanilla large-dimensional models in several generic ways: ( i) they are supersymmetric, with supersymmetry broken at sub-eV scales in the bulk but only nonlinearly realised in the Standard Model sector, leading to no MSSM superpartners for ordinary particles and many more bulk missing-energy channels, as in supersymmetric large extra dimensions (SLED); ( ii) small cycles in the more complicated extra-dimensional geometry allow some KK states to reside at TeV scales even if all six extra dimensions are nominally much larger; ( iii) a rich spectrum of string and KK states at TeV scales; and ( iv) an equally rich spectrum of very light moduli exist having unusually small (but technically natural) masses, with potentially interesting implications for cosmology and astrophysics that nonetheless evade new-force constraints. The hierarchy problem is solved in these models because the extra-dimensional volume is naturally stabilised at exponentially large values: the extra dimensions are Calabi-Yau geometries with a 4D K3 or T 4-fibration over a 2D base, with moduli stabilised within the well-established LARGE-Volume scenario. The new technical step is the use of poly-instanton corrections to the superpotential (which, unlike for simpler models, are likely to be present on K3 or T 4-fibered Calabi-Yau compactifications) to obtain a large hierarchy between the sizes of different dimensions. For several scenarios we identify

  5. Virtual Impactor for Sub-micron Aerosol Particles

    NASA Astrophysics Data System (ADS)

    Bolshakov, A. A.; Strawa, A. W.; Hallar, A. G.

    2005-12-01

    The objective of a virtual impactor is to separate out the larger particles in a flow from the smaller particles in such a way that both sizes of particles are available for sampling. A jet of particle-laden air is accelerated toward a collection probe so that a small gap exists between the acceleration nozzle and the probe. A vacuum is applied to deflect a major portion of the airstream away form the collection probe. Particles larger than a certain size have sufficient momentum so that they cross the deflected streamlines and enter the collection probe, whereas smaller particles follow the deflected streamlines. The result is that the collection probe will contain a higher concentration of larger particles than is in the initial airstream. Typically, virtual impactors are high-flow devices used to separate out particles greater than several microns in diameter. We have developed a special virtual impactor to concentrate aerosol particles of diameters between 0.5 to 1 micron for the purpose of calibrating the optical cavity ring-down instrument [1]. No similar virtual impactors are commercially available. In our design, we have exploited considerations described earlier [2-4]. Performance of our virtual impactor was evaluated in an experimental set-up using TSI 3076 nebulizer and TSI 3936 scanning mobility particle size spectrometer. Under experimental conditions optimized for the best performance of the virtual impactor, we were able to concentrate the 700-nm polystyrene particles no less than 15-fold. However, under experimental conditions optimized for calibrating our cavity ring-down instrument, a concentration factor attainable was from 4 to 5. During calibration experiments, maximum realized particle number densities were 190, 300 and 1600 cm-3 for the 900-nm, 700-nm and 500-nm spheres, respectively. This paper discusses the design of the impactor and laboratory studies verifying its performance. References: 1. A.W. Strawa, R. Castaneda, T. Owano, D.S. Baer

  6. Viewing Seasonality in 8 Megacities at 4 Microns

    NASA Astrophysics Data System (ADS)

    Tomaszewska, M. A.; Kovalskyy, V.; Small, C.; Henebry, G. M.

    2013-12-01

    The middle infrared (MIR) spectral region, between 3 and 5 microns, offers a different perspective on cities. The MIR is the mixing zone of both emitted terrestrial radiation and reflected solar radiation. The relatively long wavelengths enable views of surfaces often obscured by anthropogenic haze. Green vegetation appears very dark in the MIR due to high absorption by leaf water. In contrast, building, roofing, and paving materials reflect much MIR and exposed soils and dried vegetation reflect even more. Thus, physics dictates a strong expression of seasonality in the MIR. But is there sufficient signal in the MIR to merit it as a complementary approach for characterizing urbanized areas and monitoring their dynamics? We have explored this question in a research effort that links two NASA Interdisciplinary Science projects on the effect of cities on the environment. We focused on 8 global megacities: Beijing, Cairo, Istanbul, Mexico, Moscow, Nairobi, New Delhi, and São Paulo. We used Level 1B calibrated radiance data from band 23 (~4 microns) of the Aqua MODIS during ascending passes in 2010. These 1 km data were processed to reduce cloud cover using monthly maximum value compositing into four sensor view zenith angle (VZA) classes: 030°). SNR was higher in the summer

  7. Discovering Motifs in Biological Sequences Using the Micron Automata Processor.

    PubMed

    Roy, Indranil; Aluru, Srinivas

    2016-01-01

    Finding approximately conserved sequences, called motifs, across multiple DNA or protein sequences is an important problem in computational biology. In this paper, we consider the (l, d) motif search problem of identifying one or more motifs of length l present in at least q of the n given sequences, with each occurrence differing from the motif in at most d substitutions. The problem is known to be NP-complete, and the largest solved instance reported to date is (26,11). We propose a novel algorithm for the (l,d) motif search problem using streaming execution over a large set of non-deterministic finite automata (NFA). This solution is designed to take advantage of the micron automata processor, a new technology close to deployment that can simultaneously execute multiple NFA in parallel. We demonstrate the capability for solving much larger instances of the (l, d) motif search problem using the resources available within a single automata processor board, by estimating run-times for problem instances (39,18) and (40,17). The paper serves as a useful guide to solving problems using this new accelerator technology. PMID:26886735

  8. Tunneling of micron-sized droplets through soap films.

    PubMed

    Kim, Ildoo; Wu, X L

    2010-08-01

    When a micron-sized water droplet impacts on a freely suspended soap film with speed v(i), there exists a critical impact velocity of penetration v(C). Droplets with v(i)v(C) tunnel through it. In all cases, the film remains intact despite the fact that the droplet radius (R_{0}=26 μm) is much greater than the film thickness (0

  9. Tunneling of micron-sized droplets through soap films

    NASA Astrophysics Data System (ADS)

    Kim, Ildoo; Wu, X. L.

    2010-08-01

    When a micron-sized water droplet impacts on a freely suspended soap film with speed vi , there exists a critical impact velocity of penetration vC . Droplets with vivC tunnel through it. In all cases, the film remains intact despite the fact that the droplet radius (R0=26μm) is much greater than the film thickness (0

  10. [Micronized purified flavonoid fraction in treatment of pelvic varicose veins].

    PubMed

    Gavrilov, S G; Karalkin, A V; Moskalenko, E P; Beliaeva, E S; Ianina, A M; Kirienko, A I

    2012-01-01

    Presented herein are the results of studying efficacy of micronized purified flavonoid fraction (MPFF) in treatment of pelvic varicose veins (PVV) using reference ray-tracing methods of study. We examined a total of 85 patients with PVV. Of these, 65 subjects were found to have isolated dilatation of pelvic venous plexuses (study group), and 20 were diagnosed as having combined dilation of gonadal veins and venous plexuses of the pelvis (control group). Besides clinical examination, the patients were subjected to ultrasonographic angioscanning (USAS) and emission computed tomography (ECT) of pelvic veins before treatment and 2, 6, 12, 24, 36 and 60 months after the beginning of phlebotrophic therapy. Based on the findings of the clinical and instrumental studies, it was determined that MPFF was most efficient in patients with isolated dilatation of uterine and parametrial veins. In this group of patients, pelvic pain and other symptoms of the disease disappeared completely and the clinical effect persisted for a long time (up to 6-9 months). In the control group, venotonic therapy had a positive effect which was less pronounced as compared to the control group, and pelvic pain reappeared in the nearest time (up to 3 weeks) after withdrawal of MPFF.

  11. Micronization of silybin by the emulsion solvent diffusion method.

    PubMed

    Zhang, Zhi-Bing; Shen, Zhi-Gang; Wang, Jie-Xin; Zhang, Hai-Xia; Zhao, Hong; Chen, Jian-Feng; Yun, Jimmy

    2009-07-01

    Micronized silybin particles were successfully prepared by emulsion solvent diffusion method. Uniform spherical and rod-shaped particles with a mean size of 2.48 and 0.89 microm could be obtained using sodium dodecyl sulfate (SDS) concentration of 0.1 wt% at 30 and 15 degrees C, respectively. The characterization of silybin particles by SEM and particle size distribution (PSD) indicated that with the increase of temperature from 15 to 30 degrees C, the as-prepared particles became bigger and had a tendency to turn into spherical shapes; with the increase of SDS concentration from 0.02 to 0.1 wt%, the span of PSD became narrower while the mean particle size kept almost unchanged. XRD patterns and FT-IR spectra showed that the spherical and rod-shaped silybin particles possessed decreased crystallinity; however, the chemical structure and components were similar to those of the commercial silybin powder. Dissolution tests demonstrated that both of the spherical and rod-shaped silybin particles exhibited significantly enhanced dissolution rate when compared to the commercial silybin powder.

  12. Penetration and Effectiveness of Micronized Copper in Refractory Wood Species.

    PubMed

    Civardi, Chiara; Van den Bulcke, Jan; Schubert, Mark; Michel, Elisabeth; Butron, Maria Isabel; Boone, Matthieu N; Dierick, Manuel; Van Acker, Joris; Wick, Peter; Schwarze, Francis W M R

    2016-01-01

    The North American wood decking market mostly relies on easily treatable Southern yellow pine (SYP), which is being impregnated with micronized copper (MC) wood preservatives since 2006. These formulations are composed of copper (Cu) carbonate particles (CuCO3·Cu(OH)2), with sizes ranging from 1 nm to 250 μm, according to manufacturers. MC-treated SYP wood is protected against decay by solubilized Cu2+ ions and unreacted CuCO3·Cu(OH)2 particles that successively release Cu2+ ions (reservoir effect). The wood species used for the European wood decking market differ from the North American SYP. One of the most common species is Norway spruce wood, which is poorly treatable i.e. refractory due to the anatomical properties, like pore size and structure, and chemical composition, like pit membrane components or presence of wood extractives. Therefore, MC formulations may not suitable for refractory wood species common in the European market, despite their good performance in SYP. We evaluated the penetration effectiveness of MC azole (MCA) in easily treatable Scots pine and in refractory Norway spruce wood. We assessed the effectiveness against the Cu-tolerant wood-destroying fungus Rhodonia placenta. Our findings show that MCA cannot easily penetrate refractory wood species and could not confirm the presence of a reservoir effect. PMID:27649315

  13. Advancing dental implant surface technology--from micron- to nanotopography.

    PubMed

    Mendonça, Gustavo; Mendonça, Daniela B S; Aragão, Francisco J L; Cooper, Lyndon F

    2008-10-01

    Current trends in clinical dental implant therapy include use of endosseous dental implant surfaces embellished with nanoscale topographies. The goal of this review is to consider the role of nanoscale topographic modification of titanium substrates for the purpose of improving osseointegration. Nanotechnology offers engineers and biologists new ways of interacting with relevant biological processes. Moreover, nanotechnology has provided means of understanding and achieving cell specific functions. The various techniques that can impart nanoscale topographic features to titanium endosseous implants are described. Existing data supporting the role of nanotopography suggest that critical steps in osseointegration can be modulated by nanoscale modification of the implant surface. Important distinctions between nanoscale and micron-scale modification of the implant surface are presently considered. The advantages and disadvantages of nanoscale modification of the dental implant surface are discussed. Finally, available data concerning the current dental implant surfaces that utilize nanotopography in clinical dentistry are described. Nanoscale modification of titanium endosseous implant surfaces can alter cellular and tissue responses that may benefit osseointegration and dental implant therapy.

  14. Penetration and Effectiveness of Micronized Copper in Refractory Wood Species

    PubMed Central

    Civardi, Chiara; Van den Bulcke, Jan; Schubert, Mark; Michel, Elisabeth; Butron, Maria Isabel; Boone, Matthieu N.; Dierick, Manuel; Van Acker, Joris; Wick, Peter; Schwarze, Francis W. M. R.

    2016-01-01

    The North American wood decking market mostly relies on easily treatable Southern yellow pine (SYP), which is being impregnated with micronized copper (MC) wood preservatives since 2006. These formulations are composed of copper (Cu) carbonate particles (CuCO3·Cu(OH)2), with sizes ranging from 1 nm to 250 μm, according to manufacturers. MC-treated SYP wood is protected against decay by solubilized Cu2+ ions and unreacted CuCO3·Cu(OH)2 particles that successively release Cu2+ ions (reservoir effect). The wood species used for the European wood decking market differ from the North American SYP. One of the most common species is Norway spruce wood, which is poorly treatable i.e. refractory due to the anatomical properties, like pore size and structure, and chemical composition, like pit membrane components or presence of wood extractives. Therefore, MC formulations may not suitable for refractory wood species common in the European market, despite their good performance in SYP. We evaluated the penetration effectiveness of MC azole (MCA) in easily treatable Scots pine and in refractory Norway spruce wood. We assessed the effectiveness against the Cu-tolerant wood-destroying fungus Rhodonia placenta. Our findings show that MCA cannot easily penetrate refractory wood species and could not confirm the presence of a reservoir effect. PMID:27649315

  15. Micron-gap ThermoPhotoVoltaics (MTPV)

    NASA Astrophysics Data System (ADS)

    DiMatteo, R.; Greiff, P.; Seltzer, D.; Meulenberg, D.; Brown, E.; Carlen, E.; Kaiser, K.; Finberg, S.; Nguyen, H.; Azarkevich, J.; Baldasaro, P.; Beausang, J.; Danielson, L.; Dashiell, M.; DePoy, D.; Ehsani, H.; Topper, W.; Rahner, K.; Siergiej, R.

    2004-11-01

    This paper discusses advances made in the field of Micron-gap ThermoPhotoVoltaics (MTPV). Initial modeling has shown that MTPV may enable significant performance improvements relative to conventional far field TPV. These performance improvements include up to a 10× increase in power density, 30% to 35% fractional increase in conversion efficiency, or alternatively, reduced radiator temperature requirements to as low as 550°C. Recent experimental efforts aimed at supporting these predictions have successfully demonstrated that early current and voltage enhancements could be done repeatedly and at higher temperatures. More importantly, these efforts indicated that no unknown energy transfer process occurs reducing the potential utility of MTPV. Progress has been made by running tests with at least one of the following characteristics relative to the MTPV results reported in 2001: • Tests at over twice the temperature (900°C). • Tests at 50% smaller gaps (0.12 μm) • Tests with emitter areas from 4 to 100 times larger (16 mm2 to 4 cm2). • Tests with over 20× reduction in parasitic spacer heat flow. Remaining fundamental challenges to realizing these improvements relative to the recent breakthroughs in conventional far field TPV include reengineering the photovoltaic (PV) diode, filter, and emitter system for MTPV and engineering devices and systems that can achieve submicron vacuum gaps between surfaces with large temperature differences.

  16. Broadband dielectric microwave microscopy on micron length scales.

    PubMed

    Tselev, Alexander; Anlage, Steven M; Ma, Zhengkun; Melngailis, John

    2007-04-01

    We demonstrate that a near-field microwave microscope based on a transmission line resonator allows imaging in a substantially wide range of frequencies, so that the microscope properties approach those of a spatially resolved impedance analyzer. In the case of an electric probe, the broadband imaging can be used in a direct fashion to separate contributions from capacitive and resistive properties of a sample at length scales on the order of one micron. Using a microwave near-field microscope based on a transmission line resonator we imaged the local dielectric properties of a focused ion beam milled structure on a high-dielectric-constant Ba(0.6)Sr(0.4)TiO(3) thin film in the frequency range from 1.3 to 17.4 GHz. The electrostatic approximation breaks down already at frequencies above approximately 10 GHz for the probe geometry used, and a full-wave analysis is necessary to obtain qualitative information from the images.

  17. SUZUKI-MIYAURA COUPLING REACTIONS OF 3,5-DICHLORO-1,2,4-THIADIAZOLE

    PubMed Central

    Farahat, Abdelbasset A.; Boykin, David W.

    2014-01-01

    3,5-Dichloro-1,2,4-thiadiazole was allowed to react with different arylboronic acids under different Suzuki-Miyaura coupling conditions: at room temperature 5-aryl-3-chloro-1,2,4-thiadiazoles were obtained and at toluene reflux temperature the products were 3,5-diaryl-1,2,4-thiadiazoles. Sequential coupling reactions lead to 3,5-diaryl-1,2,4-thiadiazoles with non-identical aryl groups. The structure of 3-methoxy-5-(4-methoxyphenyl)-1,2,4-thiadiazole was established from X-ray crystallographic data. PMID:24644388

  18. Theoretical study of the thermodynamic properties, phase transition wave, and phase transition velocity for octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine

    SciTech Connect

    Long, Yao; Chen, Jun

    2015-09-21

    We develop a phonon-electron free energy model to study the thermodynamic properties and phase transitions of δ-octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine. The bulk modulus, thermal expansion coefficient, specific heat, Hugoniot curve, and phase transition curve are calculated in wide temperature and pressure ranges. The results are in agreement with the available experiments at zero pressure, and are reasonable predictions at high pressure for the lack of experiment. Two kinds of phase transition waves are investigated. We find the velocity of shock-induced phase transition wave is between 3400 m/s and 4700 m/s, and the velocity of self-sustaining phase transition wave is between 1300 m/s and 1900 m/s.

  19. Kinetics of the {beta} {yields} {delta} Solid-Solid Transition of HMX, Octahydro-1,3,5,7-Tetranitro-1,3,5,7-Tetrazocine

    SciTech Connect

    Weese, R K; Maienschein, J L; Perrino, C T

    2001-09-05

    We apply Differential Scanning Calorimetry, DSC, to measure the kinetics of the {beta} {yields} {delta} solid-solid phase transition of Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocinet HMX. Integration of the DSC signal gives a direct measurement of degree of conversion. We apply 1st order kinetics, the Ozawa method, and isoconversional analysis to show that the phase transition is not a simple one-step reaction, but instead is a complex combination of steps. The range of activation energies found in this work, centering around 500 kJ/mol, is higher than previously reported values. We discuss possible reasons for the higher activation energies measured here.

  20. Thermochemistry of uracils. Experimental and computational enthalpies of formation of 5,6-dimethyl-, 1,3,5-trimethyl-, and 1,3,5,6-tetramethyluracils.

    PubMed

    Notario, Rafael; Emel'yanenko, Vladimir N; Roux, María Victoria; Ros, Francisco; Verevkin, Sergey P; Chickos, James S; Liebman, Joel F

    2013-01-10

    We describe in the current paper an experimental and computational study of three methylated uracils, in particular, the 5,6-dimethyl-, 1,3,5-trimethyl-, and 1,3,5,6-tetramethyl derivatives. The values of the standard (p(0) = 0.1 MPa) molar enthalpies of formation in the gas phase at T = 298.15 K have been determined. The energies of combustion were measured by static bomb combustion calorimetry, and from the results obtained, the standard molar enthalpies of formation in the crystalline state at T = 298.15 K were calculated. The enthalpies of sublimation were determined using the transpiration method in a saturated N(2) stream. Values of -(376.2 ± 2.6), -(355.9 ± 3.0), and -(381.7 ± 2.8) kJ·mol(-1) for the gas-phase enthalpies of formation at T = 298.15 K of 5,6-dimethyluracil, 1,3,5-trimethyluracil, and 1,3,5,6-tetramethyluracil, respectively, were obtained from the experimental thermochemical study. An extended theoretical study with the G3 and the G4 quantum-chemical methods has been carried out for all the possible methylated uracils. There is a very good agreement between experimental and calculated enthalpies of formation for the three derivatives studied. A Free-Wilson analysis on G4-calculated enthalpies of formation has been carried out, and the contribution of methylation in the different positions of the uracil ring has been estimated. PMID:23215007

  1. Abundance and diversity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX)-metabolizing bacteria in UXO-contaminated marine sediments.

    PubMed

    Zhao, Jian-Shen; Manno, Dominic; Hawari, Jalal

    2007-03-01

    Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) is a toxic explosive known to be resistant to biodegradation. In this study, we found that sediment collected from two unexploded ordnance (UXO) disposal sites (UXO-3, UXO-5) and one nearby reference site (midref) in Hawaii contained anaerobic bacteria capable of removing HMX. Two groups of HMX-removing bacteria were found in UXO-5: group I contained aerotolerant anaerobes and microaerophiles, and group II contained facultative anaerobes. In UXO-3 and midref sediments, HMX-metabolizing bacteria were strictly anaerobic (group III and group IV). Using 16S rRNA sequencing, group I was assigned to a novel phylogenetic cluster of Clostridiales, and groups II and III were related to Paenibacillus and Tepidibacter of Firmicutes, respectively. Group IV bacteria were identified as Desulfovibrio of Deltaproteobacteria. Using [UL-(14)C]-HMX, group IV isolates were found to mineralize HMX (26.8% in 308 d) as determined by liberated (14)CO(2), but negligible mineralization was observed in groups I-III. Resting cells of isolates metabolized HMX to N(2)O and HCHO via the intermediary formation of 1-nitroso-octahydro-3,5,7-trinitro-1,3,5,7-tetrazocine together with methylenedinitramine. These experimental findings suggest that HMX biotransformation occurred either via initial denitration followed by ring cleavage or via reduction of one or more of the N-NO(2) group(s) to the corresponding N-NO bond(s) prior to ring cleavage.

  2. An overview on in situ micronization technique - An emerging novel concept in advanced drug delivery.

    PubMed

    Vandana, K R; Prasanna Raju, Y; Harini Chowdary, V; Sushma, M; Vijay Kumar, N

    2014-09-01

    The use of drug powders containing micronized drug particles has been increasing in several pharmaceutical dosage forms to overcome the dissolution and bioavailability problems. Most of the newly developed drugs are poorly water soluble which limits dissolution rate and bioavailability. The dissolution rate can be enhanced by micronization of the drug particles. The properties of the micronized drug substance such as particle size, size distribution, shape, surface properties, and agglomeration behaviour and powder flow are affected by the type of micronization technique used. Mechanical communition, spray drying and supercritical fluid (SCF) technology are the most commonly employed techniques for production of micronized drug particles but the characteristics of the resulting drug product cannot be controlled using these techniques. Hence, a newer technique called in situ micronization is developed in order to overcome the limitations associated with the other techniques. This review summarizes the existing knowledge on in situ micronization techniques. The properties of the resulting drug substance obtained by in situ micronization were also compared.

  3. Method of producing carbon coated nano- and micron-scale particles

    DOEpatents

    Perry, W. Lee; Weigle, John C; Phillips, Jonathan

    2013-12-17

    A method of making carbon-coated nano- or micron-scale particles comprising entraining particles in an aerosol gas, providing a carbon-containing gas, providing a plasma gas, mixing the aerosol gas, the carbon-containing gas, and the plasma gas proximate a torch, bombarding the mixed gases with microwaves, and collecting resulting carbon-coated nano- or micron-scale particles.

  4. Wavelength Shifts of the 7.7 Micron Emission Band in Reflection Nebulae

    NASA Technical Reports Server (NTRS)

    Bregman, Jesse; Temi, Pasquale

    2003-01-01

    Using spatial-spectral data cubes of reflection nebulae obtained by ISOCAM, we have observed a shift in the central wavelength of the 7.7 micron band within several reflection nebulae. The band shifts progressively from approx. 7.8 microns near the edge of the nebulae to approx. 7.6 microns towards the center of the nebulae. The ratio of the 11.3/7.7 micron bands also changes with distance from the central star, first rising from the center towards the edge of the nebula, then falling at the largest distances from the star, consistent with the 11.3/7.7 micron band ratio being controlled by the PAH ionization state. The behavior of the 7.7 micron band center can be explained either by assuming that anions are the origin of the 7.85 micron band and cations the 7.65 micron band, or that the band center wavelength depends on the chemical nature of the PAHs.

  5. An overview on in situ micronization technique – An emerging novel concept in advanced drug delivery

    PubMed Central

    Vandana, K.R.; Prasanna Raju, Y.; Harini Chowdary, V.; Sushma, M.; Vijay Kumar, N.

    2013-01-01

    The use of drug powders containing micronized drug particles has been increasing in several pharmaceutical dosage forms to overcome the dissolution and bioavailability problems. Most of the newly developed drugs are poorly water soluble which limits dissolution rate and bioavailability. The dissolution rate can be enhanced by micronization of the drug particles. The properties of the micronized drug substance such as particle size, size distribution, shape, surface properties, and agglomeration behaviour and powder flow are affected by the type of micronization technique used. Mechanical communition, spray drying and supercritical fluid (SCF) technology are the most commonly employed techniques for production of micronized drug particles but the characteristics of the resulting drug product cannot be controlled using these techniques. Hence, a newer technique called in situ micronization is developed in order to overcome the limitations associated with the other techniques. This review summarizes the existing knowledge on in situ micronization techniques. The properties of the resulting drug substance obtained by in situ micronization were also compared. PMID:25161371

  6. Separating the signal from the noise: Expanding flow cytometry into the sub-micron range.

    EPA Science Inventory

    Cytometry Part A Special Section: Separating the signal from the noise: Expanding flow cytometry into the sub-micron range. The current Cytometry Part A Special Section presents three studies that utilize cytometers to study sub-micron particles. The three studies involve the 1...

  7. A microring resonator sensor for sensitive detection of 1,3,5-trinitrotoluene (TNT).

    PubMed

    Orghici, Rozalia; Lützow, Peter; Burgmeier, Jörg; Koch, Jan; Heidrich, Helmut; Schade, Wolfgang; Welschoff, Nina; Waldvogel, Siegfried

    2010-01-01

    A microring resonator sensor device for sensitive detection of the explosive 1,3,5-trinitrotoluene (TNT) is presented. It is based on the combination of a silicon microring resonator and tailored receptor molecules. PMID:22163576

  8. A microring resonator sensor for sensitive detection of 1,3,5-trinitrotoluene (TNT).

    PubMed

    Orghici, Rozalia; Lützow, Peter; Burgmeier, Jörg; Koch, Jan; Heidrich, Helmut; Schade, Wolfgang; Welschoff, Nina; Waldvogel, Siegfried

    2010-01-01

    A microring resonator sensor device for sensitive detection of the explosive 1,3,5-trinitrotoluene (TNT) is presented. It is based on the combination of a silicon microring resonator and tailored receptor molecules.

  9. A Microring Resonator Sensor for Sensitive Detection of 1,3,5-Trinitrotoluene (TNT)

    PubMed Central

    Orghici, Rozalia; Lützow, Peter; Burgmeier, Jörg; Koch, Jan; Heidrich, Helmut; Schade, Wolfgang; Welschoff, Nina; Waldvogel, Siegfried

    2010-01-01

    A microring resonator sensor device for sensitive detection of the explosive 1,3,5-trinitrotoluene (TNT) is presented. It is based on the combination of a silicon microring resonator and tailored receptor molecules. PMID:22163576

  10. Wideband digital spectrum analyzer

    NASA Technical Reports Server (NTRS)

    Morris, G. A., Jr.; Wilck, H. C.

    1979-01-01

    Modular spectrum analyzer consisting of RF receiver, fast fourier transform spectrum analyzer, and data processor samples stochastic signals in 220 channels. Construction reduces design and fabrication costs of assembled unit.

  11. Autism Spectrum Disorder (ASD)

    MedlinePlus

    ... spectrum disorder (ASD) is a group of developmental disabilities that can cause significant social, communication and behavioral ... for autism spectrum disorder (ASD) and other developmental disabilities. More E-mail Your Friends "Children with autism ...

  12. 20-micron transparency and atmospheric water vapor at the Wyoming Infrared Observatory

    NASA Technical Reports Server (NTRS)

    Grasdalen, G. L.; Gehrz, R. D.; Hackwell, J. A.; Freedman, R.

    1985-01-01

    The atmospheric transparency at 19.5 and 23 microns from the Wyoming Infrared Observatory over the past six years has been examined. It is found that the transparency is largely controlled by the season. Four months: June, July, August, and September have very poor 20-micron transparency. During the rest of the year the transparency is usually quite good at 19.5 microns and moderately good at 23 microns. Using rawinsonde data and theoretical calculations for the expected infrared transparency, the measures of 20-micron transparency were calibrated in terms of atmospheric water-vapor content. The water vapor over the Wyoming Infrared Observatory is found to compare favorably with that above other proposed or developed sites: Mauna Kea, Mount Graham, and Wheeler Peak.

  13. [Results of treating forearm bone shaft fractures with a 3.5 mm self compressive plate].

    PubMed

    Małecki, P; Kaleta, M; Tokarowski, A; Kusz, D; Wójcik, B

    1997-01-01

    Results of 29 forearm bones shaft fracture treatment with 3.5mm self compressive plate in 26 patients aged 18-64 (mean 33) are presented. Open reduction with 3.5mm self compressive plate fixation has been performed in all cases. Anderson et al criteria were used to assess functional and radiological outcome. Excellent and good functional results were achieved in 25 cases, one was rated fair, no poor results were observed. PMID:9490253

  14. PI(3,5)P2 biosynthesis regulates oligodendrocyte differentiation by intrinsic and extrinsic mechanisms

    PubMed Central

    Mironova, Yevgeniya A; Lenk, Guy M; Lin, Jing-Ping; Lee, Seung Joon; Twiss, Jeffery L; Vaccari, Ilaria; Bolino, Alessandra; Havton, Leif A; Min, Sang H; Abrams, Charles S; Shrager, Peter; Meisler, Miriam H; Giger, Roman J

    2016-01-01

    Proper development of the CNS axon-glia unit requires bi-directional communication between axons and oligodendrocytes (OLs). We show that the signaling lipid phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2] is required in neurons and in OLs for normal CNS myelination. In mice, mutations of Fig4, Pikfyve or Vac14, encoding key components of the PI(3,5)P2 biosynthetic complex, each lead to impaired OL maturation, severe CNS hypomyelination and delayed propagation of compound action potentials. Primary OLs deficient in Fig4 accumulate large LAMP1+ and Rab7+ vesicular structures and exhibit reduced membrane sheet expansion. PI(3,5)P2 deficiency leads to accumulation of myelin-associated glycoprotein (MAG) in LAMP1+perinuclear vesicles that fail to migrate to the nascent myelin sheet. Live-cell imaging of OLs after genetic or pharmacological inhibition of PI(3,5)P2 synthesis revealed impaired trafficking of plasma membrane-derived MAG through the endolysosomal system in primary cells and brain tissue. Collectively, our studies identify PI(3,5)P2 as a key regulator of myelin membrane trafficking and myelinogenesis. DOI: http://dx.doi.org/10.7554/eLife.13023.001 PMID:27008179

  15. The ML1Nx2 Phosphatidylinositol 3,5-Bisphosphate Probe Shows Poor Selectivity in Cells.

    PubMed

    Hammond, Gerald R V; Takasuga, Shunsuke; Sasaki, Takehiko; Balla, Tamas

    2015-01-01

    Phosphatidylinositol (3,5)-bisphosphate (PtdIns(3,5)P2) is a quantitatively minor phospholipid in eukaryotic cells that plays a fundamental role in regulating endocytic membrane traffic. Despite its clear importance for cellular function and organism physiology, mechanistic details of its biology have so far not been fully elucidated. In part, this is due to a lack of experimental tools that specifically probe for PtdIns(3,5)P2 in cells to unambiguously identify its dynamics and site(s) of action. In this study, we have evaluated a recently reported PtdIns(3,5)P2 biosensor, GFP-ML1Nx2, for its veracity as such a probe. We report that, in live cells, the localization of this biosensor to sub-cellular compartments is largely independent of PtdIns(3,5)P2, as assessed after pharmacological, chemical genetic or genomic interventions that block the lipid's synthesis. We therefore conclude that it is unwise to interpret the localization of ML1Nx2 as a true and unbiased biosensor for PtdIns(3,5)P2.

  16. PI(3,5)P2 biosynthesis regulates oligodendrocyte differentiation by intrinsic and extrinsic mechanisms.

    PubMed

    Mironova, Yevgeniya A; Lenk, Guy M; Lin, Jing-Ping; Lee, Seung Joon; Twiss, Jeffery L; Vaccari, Ilaria; Bolino, Alessandra; Havton, Leif A; Min, Sang H; Abrams, Charles S; Shrager, Peter; Meisler, Miriam H; Giger, Roman J

    2016-01-01

    Proper development of the CNS axon-glia unit requires bi-directional communication between axons and oligodendrocytes (OLs). We show that the signaling lipid phosphatidylinositol-3,5-bisphosphate [PI(3,5)P2] is required in neurons and in OLs for normal CNS myelination. In mice, mutations of Fig4, Pikfyve or Vac14, encoding key components of the PI(3,5)P2 biosynthetic complex, each lead to impaired OL maturation, severe CNS hypomyelination and delayed propagation of compound action potentials. Primary OLs deficient in Fig4 accumulate large LAMP1(+) and Rab7(+) vesicular structures and exhibit reduced membrane sheet expansion. PI(3,5)P2 deficiency leads to accumulation of myelin-associated glycoprotein (MAG) in LAMP1(+)perinuclear vesicles that fail to migrate to the nascent myelin sheet. Live-cell imaging of OLs after genetic or pharmacological inhibition of PI(3,5)P2 synthesis revealed impaired trafficking of plasma membrane-derived MAG through the endolysosomal system in primary cells and brain tissue. Collectively, our studies identify PI(3,5)P2 as a key regulator of myelin membrane trafficking and myelinogenesis. PMID:27008179

  17. Simplified Digital Spectrum Analyzer

    NASA Technical Reports Server (NTRS)

    Cole, Steven W.

    1992-01-01

    Spectrum analyzer computes approximate cross-correlations between noisy input signal and reference signal of known frequency, yielding measure of amplitude of sinusoidal component of input. Complexity and power consumed less than other digital spectrum analyzers. Performs no multiplications, and because processes data on each frequency independently, focuses on narrow spectral range without processing data on rest of spectrum.

  18. The AGN Content of the Micron all Sky Survey

    NASA Astrophysics Data System (ADS)

    Cutri, R. M.

    2000-01-01

    The Two Micron All Sky Survey (2MASS) began routine operations from its northern facility on Mt. Hopkins, AZ in June of 1997, and from its southern facility on Cerro Tololo, Chile in March of 1998. At each site, highly automated 1.3 m telescopes equipped with identical 3-channel cameras, are systematically imaging the sky in three near infrared wavelength bands, J (1.25 um), H (1.65 um) and K-s (2.17 um). The Survey will ultimately produce an Image Atlas containing nearly two million 512 x 1024 pixel images (1 arcsec/pix) in the three colors, a highly complete and reliable catalog containing approx. 300 million point sources having SNR greater than 10 photometry at J less or = 15.8, H less or = 15.1 and K-s less or = 14.3 mag. and an astrometric accuracy greater than 0.511 RMS, and a catalog of 1-2 million resolved sources, primarily galaxies, having SNR greater than 10 photometric accuracy at J less than or = 15.5, H less than or = 14.8 and K-s less than or = 13.5 mag. The 2MASS Sampler, an introductory set of data, was released to the community in December of 1998 (see http://www.ipac.caltech.edu/2mass/). We review the near IR and optical/IR properties of "conventional" QSOs from UV and optical samples, and estimate the number that will be detected by 2MASS. We also discuss 2MASS's ability to test for for new populations of extremely red AGN that have been missed by UV and Visual surveys, as suggested by from IRAS and radio studies. Results of spectroscopic follow-up of 2MASS-selected new AGN candidates will also be presented.

  19. A micron resolution optical scanner for characterization of silicon detectors

    SciTech Connect

    Shukla, R. A.; Dugad, S. R. Gopal, A. V.; Gupta, S. K.; Prabhu, S. S.; Garde, C. S.

    2014-02-15

    The emergence of high position resolution (∼10 μm) silicon detectors in recent times have highlighted the urgent need for the development of new automated optical scanners of micron level resolution suited for characterizing microscopic features of these detectors. More specifically, for the newly developed silicon photo-multipliers (SiPM) that are compact, possessing excellent photon detection efficiency with gain comparable to photo-multiplier tube. In a short time, since their invention the SiPMs are already being widely used in several high-energy physics and astrophysics experiments as the photon readout element. The SiPM is a high quantum efficiency, multi-pixel photon counting detector with fast timing and high gain. The presence of a wide variety of photo sensitive silicon detectors with high spatial resolution requires their performance evaluation to be carried out by photon beams of very compact spot size. We have designed a high resolution optical scanner that provides a monochromatic focused beam on a target plane. The transverse size of the beam was measured by the knife-edge method to be 1.7 μm at 1 − σ level. Since the beam size was an order of magnitude smaller than the typical feature size of silicon detectors, this optical scanner can be used for selective excitation of these detectors. The design and operational details of the optical scanner, high precision programmed movement of target plane (0.1 μm) integrated with general purpose data acquisition system developed for recording static and transient response photo sensitive silicon detector are reported in this paper. Entire functionality of scanner is validated by using it for selective excitation of individual pixels in a SiPM and identifying response of active and dead regions within SiPM. Results from these studies are presented in this paper.

  20. Asteroid (101955) 1999 RQ36: Spectroscopy from 0.4 to 2.5 microns and Meteorite Analogs

    NASA Astrophysics Data System (ADS)

    Clark, Beth Ellen; Binzel, R. P.; Howell, E.; Cloutis, E. A.; Ockert-Bell, M.; Christensen, P.; Barucci, M. A.; DeMeo, F.; Lauretta, D.; Connolly, H., Jr.; Soderberg, A.; Hergenrother, C.; Lim, L.

    2010-10-01

    We present reflectance spectra from 0.4 to 2.5 microns of asteroid (101955) 1999 RQ36, the target of the proposed OSIRIS-REx spacecraft mission. The visible spectral data were obtained at the McDonald Observatory 2.1-m telescope with the ES2 spectrograph. The infrared spectral data were obtained at the NASA Infrared Telescope Facility using the SpeX instrument. The average visible spectrum is combined with the average near-infrared wavelength spectrum to form a composite spectrum. We use three methods to constrain the compositional information in the composite spectrum of asteroid (101955) 1999 RQ36 (hereafter RQ36). First, we perform a least-squares search for meteorite spectral analogs using 15,000 spectra from the RELAB database. Three most likely meteorite analogs are proposed based on the least-squares search. Next, six spectral parameters are measured for RQ36 and their values are compared with the ranges in parameter values established by sets of RELAB spectra representing relevant spectrally measured meteorite classes. A most likely meteorite analog group is proposed based on the depth of overlap in parameter values. The results of the least-squares search and the parametric comparisons point to CIs and/or CMs as the most likely meteorite analogs for RQ36, and CKs and ureilites as the least likely. We speculate that RQ36 is composed of a CM1-like material. Finally, RQ36 is compared to other B-type asteroids measured by Clark et al. (2010 JGR 15) and is found to be most consistent with the Themis Group B-types. This is particularly interesting because asteroid 24 Themis was recently discovered to have H2O ice on the surface (Rivkin and Emery 2010, Nature 464; Campins et al. 2010, Nature 464).

  1. The Zodiacal Emission Spectrum as Determined by COBE and its Implications

    NASA Technical Reports Server (NTRS)

    Fixsen, D. J.; Dwek, Eli; Oliversen, R. (Technical Monitor)

    2002-01-01

    We combine observations from the DIRBE and FIRAS instruments on the COBE satellite to derive an annually-averaged spectrum of the zodiacal cloud in the 10 to 1000 micron wavelength region. The spectrum exhibits a break at approx. 150 microns which indicates a sharp break in the dust size distribution at a radius of about 30 microns The spectrum can be fit with a single blackbody with a lambda(exp -2) emissivity law beyond 150 microns and a temperature of 240 K. We also used a more realistic characterization of the cloud to fit the spectrum, including a distribution of dust temperatures, representing different dust compositions and distances from the sun, as well as a realistic representation of the spatial distribution of the dust. We show that amorphous carbon and silicate dust with respective temperatures of 280 and 274 K at 1 AU, and size distributions with a break at grain radii of 14 and 32 microns, can provide a good fit to the average zodiacal dust spectrum. The total mass of the zodiacal cloud is 2 to 11 Eg (Eg=10(exp 18) g), depending on the grain composition. The lifetime of the cloud, against particle loss by Poynting- Robertson drag and the effects of solar wind, is about 10(exp 5) yr. The required replenishment rate is approx. 10(exp 14) g/yr. If this is provided by asteroid belt alone, the asteroids lifetime would be approx. 3 x 10(exp 10) yr. But comets and Kuiper belt objects may also contribute to the zodiacal cloud.

  2. The spectrum of Saturn from 1990 to 2230/cm - Abundances of AsH3, CH3D, CO, GeH4, NH3, and PH3

    NASA Technical Reports Server (NTRS)

    Noll, Keith S.; Larson, Harold P.

    1991-01-01

    An analysis is presented of the abundances and vertical distributions of all known absorbers in the 5-micron spectrum of Saturn, in view of previously unpublished observations, synthetic spectra of each atmospheric constituent, and an atmospheric model for synthesizing Saturn's spectrum in order to make comparisons with observations. The model used encompasses the abundances of all gaseous absorbers, their vertical distributions, clouds, and the thermal and reflected solar components of planetary flux. A coherent understanding is in this way obtained of both the many variables affecting Saturn's 5-micron spectrum and the similarities between Jupiter and Saturn.

  3. Calibration and Validation of WRF 3.0-CLM3.5 in Snowpack Simulations

    NASA Astrophysics Data System (ADS)

    Jin, J.; Wen, L.; Subin, Z. M.; Miller, N. L.

    2009-12-01

    The Community Land Model version 3.5 (CLM3.5) developed by the National Center for Atmospheric Research (NCAR) was coupled into the Weather Research and Forecasting (WRF) Model version 3.0. The performance of WRF3.0-CLM3.5 in simulating snowpack was extensively evaluated with in-situ observations from a mountainous site called Col de Porte, located in northern Alps region of France, and the Columbia River Basin, located in the northwestern United States. CLM3.5 was configured with a five-layer snow scheme, and includes snow compaction and liquid water transfer processes, and a sophisticated snow albedo scheme. WRF3.0-CLM3.5 was forced with the National Center for Atmospheric Research/National Centers for Environmental Prediction Reanalysis data to simulate for the 1988-1989 snow season for the Col de Porte site and the 2001-2002 season for the Columbia River Basin, with 60km-20km two-way nested domains. The initial simulations show that WRF3.0-CLM3.5 significantly improves snow simulations when compared to those produced with the WRF3.0 coupled to the Noah land surface scheme at the both study sites. However, WRF3.0-CLM3.5 still tends to underestimate the observed snowpack. Calibration with the observed data from the Col de Porte site indicates that the snow water content bias mainly results from stronger, high elevation incoming solar radiation. An adjustment for the radiation scheme in WRF3.0 was made to reduce the incoming radiation to better fit with the observations. This adjustment improves snow simulations at both Col de Porte site and the Columbia River Basin. Additional offline snow simulations with CLM3.5 driven with observed forcing data were performed at the Col de Porte site. These offline simulations are compared to the results produced with the coupled WRF3.0-CLM3.5. Through this comparison, snow-atmosphere interactions are quantitatively indentified. The improved snow simulations in WRF3.0-CLM3.5 will benefit regional hydro-climate research and

  4. Characterization of 100 micron thick positive photoresist on 300-mm wafers

    NASA Astrophysics Data System (ADS)

    Flack, Warren W.; Nguyen, Ha-Ai; Capsuto, Elliott; Abreau, Kelly

    2005-05-01

    The widespread adoption of advanced packaging techniques is driven by device performance and chip form factor considerations. Flip chip packaging is currently growing at a thirty percent compound annual rate and it is expected that in the near future over sixty percent of all 300 mm wafers will be bumped. To ensure optimal productivity and cost of ownership it is imperative to provide lithographic equipment and materials that are optimized for these applications. Due to the constantly shrinking bump pitch, it is critical to show excellent CD uniformity across the entire 300 mm wafer surface for feature sizes as small as 70 microns. Flip chip packaging as well as Nanotechnology (MEMS) applications frequently use one or more very thick photoresist layers for electroplating applications. The plating levels require a photosensitive polymer material capable of coating, exposing and electroplating with conventional equipment and standard ancillary process chemicals. Additionally the process times for coating, baking, exposure and development must be considered since these impacts the overall cost of ownership of the lithography cell. For thick photoresist layers the sidewall profile, plating resistance and postplating stripability are important characteristics. This study will characterize a novel single coat, positive tone photoresist (ShinEtsu SIPR 7120-20) used in electroplating levels up to 100 μm thick on 300 mm wafers exposed with the Ultratech Spectrum 300e2 stepper and coated and developed with a Steag Hamatech Modutrack system. Process capability is determined by analyzing photoresist film thickness uniformity and critical dimension (CD) control across the wafer. Basic photoresist characterization techniques such as cross sectional SEM analysis are used to establish lithographic capabilities. This study shows excellent adhesion to copper with no surface treatment and no photoresist popping during exposure or post exposure bake (PEB). High aspect ratio, lead

  5. Observations and analysis of the Jovian spectrum in the 10-micron nu-2 band of NH3

    NASA Technical Reports Server (NTRS)

    Lacy, J. H.; Larrabee, A. I.; Wollman, E. R.; Geballe, T. R.; Townes, C. H.; Bregman, J. D.; Rank, D. M.

    1975-01-01

    Observations of the nu-2 band of NH3 in the Jovian atmosphere have been made at resolutions varying from 4 per cm to 0.15 per cm. The observations have been interpreted by computation of synthetic atmospheric spectra. Derived atmospheric parameters include a pressure of 0.5 atm at 145 K and a minimum temperature of 118 K.

  6. The phosphatidylinositol 3,5-bisphosphate (PI(3,5)P2)-dependent Tup1 conversion (PIPTC) regulates metabolic reprogramming from glycolysis to gluconeogenesis.

    PubMed

    Han, Bong-Kwan; Emr, Scott D

    2013-07-12

    Glucose/carbon metabolism is a fundamental cellular process in living cells. In response to varying environments, eukaryotic cells reprogram their glucose/carbon metabolism between aerobic or anaerobic glycolysis, oxidative phosphorylation, and/or gluconeogenesis. The distinct type of glucose/carbon metabolism that a cell carries out has significant effects on the cell's proliferation and differentiation. However, it is poorly understood how the reprogramming of glucose/carbon metabolism is regulated. Here, we report a novel endosomal PI(3,5)P2 lipid-dependent regulatory mechanism that is required for metabolic reprogramming from glycolysis to gluconeogenesis in Saccharomyces cerevisiae. Certain gluconeogenesis genes, such as FBP1 (encoding fructose-1,6-bisphosphatase 1) and ICL1 (encoding isocitrate lyase 1) are under control of the Mig1 repressor and Cyc8-Tup1 corepressor complex. We previously identified the PI(3,5)P2-dependent Tup1 conversion (PIPTC), a mechanism to convert Cyc8-Tup1 corepressor to Cti6-Cyc8-Tup1 coactivator. We demonstrate that the PIPTC plays a critical role for transcriptional activation of FBP1 and ICL1. Furthermore, without the PIPTC, the Cat8 and Sip4 transcriptional activators cannot be efficiently recruited to the promoters of FBP1 and ICL1, suggesting a key role for the PIPTC in remodulating the chromatin architecture at the promoters. Our findings expand our understanding of the regulatory mechanisms for metabolic reprogramming in eukaryotes to include key regulation steps outside the nucleus. Given that Tup1 and the metabolic enzymes that control PI(3,5)P2 are highly conserved among eukaryotes, our findings may provide important insights toward understanding glucose/carbon metabolic reprogramming in other eukaryotes, including humans.

  7. Cleavage of carbon-nitrogen bond in 1,3,5-tri-tert-butyl-1,3,5-triazacyclohexane by copper(I) bromide

    NASA Astrophysics Data System (ADS)

    Khatua, Suman; Majumdar, Amit

    2016-09-01

    Reactions of CuCl, CuCl2 and CuBr2 with 1,3,5-tri-tert-butyl-1,3,5-triazacyclohexane (tBu3tach) resulted in the formation of [(tBu3tach-H)+(CuCl2)] (1), [(tBu3tach)(CuCl2)] (2) and [(tBu3tach-H)+(CuBr2)] (3) respectively. Interestingly, CuBr was found to mediate the cleavage of the C-N bonds of tBu3tach in a vast range of solvents, namely, chloroform, dichloromethane, tetrahydrofuran, acetonitrile and methanol to yield [Cu4Br4(tBuNCH2)4] (4) and stands as an example of C-N bond cleavage of 1,3,5-triazacyclohexane rings by copper salts. Compounds 1 and 3 contains amidinium cations and are unstable in solution towards the release of copper. The release of copper from 3 in solution was confirmed by the isolation of the compound, [CuBr(MeCN)] (5). Formation of the amidinium cations [(tBu3tach-H)+] in 1 and 3 may be avoided by the use of PPh3 to yield [(tBu3tach)Cu(PPh3)](PF6) (6), while the coordinated N-tert-butylmethanimine (tBuNCH2) in 4 could be replaced by PPh3 to yield [Cu4Br4(PPh3)4] (7). Complexes 1-7 are characterized by a combination of single crystal X-ray structure determination and/or elemental analysis, NMR, IR, and UV-Vis spectroscopy, and Mass spectrometry.

  8. A comparison of telescopic and Phobos-2 ISM spectra of Mars in the short-wave near-infrared (0.76-1.02 microns)

    NASA Technical Reports Server (NTRS)

    Bell, James F., III; Mustard, John F.

    1993-01-01

    Recent analyses of near-IR (0.76-3.16 microns) Mars surface reflectance spectra obtained by the Phobos-2 ISM instrument during early 1989 have revealed the presence of substantial variability in surface spectral properties. Strong absorption features seen in the 0.85-1.05 micron region are up to 10-15 percent deep relative to the local continuum and have been interpreted as evidence of Fe(2+) and Fe(3+) bearing minerals (pyroxenes and iron oxides, respectively). Though these observed band depths are comparable to those seen in laboratory reflectance spectra, they are up to three times larger than most previously reported band depths for Mars spectra at these wavelengths. Six regions of variable albedo and geologic setting were identified where ISM and 1988 opposition telescopic coverage either overlapped physically or sampled the same surface geologic unit. The areal sizes and positions of the regions measured telescopically were compiled by Bell et al. ISM pixels falling within these spots were averaged to produce a spatially convolved spectrum that simulates what would have been seen telescopically. To facilitate comparisons of absorption band positions and relative strengths, the convolved ISM data and the 1988 telescopic spectra were scaled to unity at 0.81 microns and are presented. The data have also been convolved to equivalent band pass normalized reflectances in the region of spectral overlap. A scatter diagram of telescopic vs. ISM reflectances is shown. The results from the investigation are discussed.

  9. Micronization increases vitamin E carrying and releasing abilities of insoluble fiber.

    PubMed

    Hsu, Pang-Kuei; Chien, Po-Jung; Chau, Chi-Fai

    2008-03-26

    This study was to investigate the effects of micronization on vitamin-carrying capacity and slow-release ability of carambola (starfruit) insoluble fiber (IF) and cellulose using in vitro and in vivomodels. Upon micronization, carambola IF (8.1 microm) underwent structural changes to expose more functional groups in the fiber matrix and to exhibit higher oil-holding capacity ( approximately 20.4-fold). Micronized fibers in forms of fiber-vitamin composites, particularly the micronized carambola IF-vitamin composite, were capable of carrying vitamin E (alpha-tocopherol) up to 9.6-fold over their unmicronized forms and releasing nutrient gradually. Animal studies demonstrated that the adminstration of micronized carambola IF-vitamin composite could maintain the plasma vitamin E of rats at relatively higher levels (2.1-3.6-fold of the initial values) for at least 5 h. The results suggested that micronized fibers, particularly the micronized carambola IF, could be exploited as potential nutrient carriers in food applications and also be used to produce slow-release formulations.

  10. The 16-39 micron spectroscopy of oxygen-rich stars

    NASA Technical Reports Server (NTRS)

    Forrest, W. J.; Mccarthy, W. J.; Houck, J. R.

    1979-01-01

    Airborne observations of the 16-39 microns spectra of ten oxygen-rich stars with excess emission in the infrared was obtained. The stars show excess emission attributed to circumstellar dust grains in the 16-39 microns region in the form of a broad hump peaking near 18 microns and falling smoothly to longer wavelengths. The emission is similar in character to the emission from the Trapezium region of the Orion nebula indicating the grain materials are quite similar in these objects. The existence of a feature in the 20 microns region is consistent with the 0-Si-0 bending resonance expected for silicate material. The lack of any sharp structure in the spectra indicates the silicate is in an amorphous, disordered form. A simple model of small grains of carbonaceous chondrite silicate material in a diffuse circumstellar envelope is shown to give a good qualitative fit to the observed 8-39 microns circumstellar spectra. Comparison of the observed spectra with the model spectra indicates the grain emissivity falls as 1/lambda squared from 20 microns to 40 microns.

  11. Electron shuttle-mediated biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine adsorbed to granular activated carbon.

    PubMed

    Millerick, Kayleigh; Drew, Scott R; Finneran, Kevin T

    2013-08-01

    Granular activated carbon (GAC) effectively removes hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) from groundwater but generates RDX-laden GAC that must be disposed of or regenerated. Batch reactors containing GAC to which RDX was preadsorbed were used in experiments to test the potential for adsorbed RDX reduction and daughter product formation using (i) chemically reduced anthrahydroquinone-2,6-disulfonate (AH2QDS), (ii) resting Geobacter metallireducens strain GS-15, and (iii) a combined system containing AQDS and GS-15. Approximately 97.0% of the adsorbed RDX was transformed in each of these experimental systems by 90 h. Chemically reduced AQDS (AH2QDS) transformed 99.2% of adsorbed RDX; formaldehyde was produced rapidly and was stoichiometric (3 mol HCHO per mol RDX). Geobacter metallireducens also reduced RDX with and without AQDS present. This is the first study to demonstrate biological transformation of RDX adsorbed to GAC. Formaldehyde increased and then decreased in biological systems, suggesting a previously unreported capacity for G. metallireducens to oxidize formaldehyde, which was confirmed with resting cell suspensions. These data suggest the masses of GAC waste currently produced by activated carbon at RDX remediation sites can be minimized, decreasing the carbon footprint of the treatment technology. Alternatively, this strategy may be used to develop a Bio-GAC system for ex situ RDX treatment. PMID:23837558

  12. Fate of the explosive hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in soil and bioaccumulation in bush bean hydroponic plants

    SciTech Connect

    Harvey, S.D.; Fellows, R.J.; Cataldo, D.A.; Bean, R.M. )

    1991-01-01

    Soils amended with [[sup 14]C]hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) were sampled over 60 d and subjected to exhaustive Soxhlet extraction followed by HPLC analysis. RDX was the only radiolabeled compound observed in soil extracts. Emission of volatile organics and [sup 14]CO[sub 2] from soil accounted for only 0.31 % of the amended radiolabel. Mass balance for RDX-amended soil was better than 84% throughout the two-month study. The analytical method developed for plants involved acid hydrolysis, solvent extraction, fractionation on Florisil adsorbent and separation by HPLC. The described methodology allowed for RDX recovery of 86 [+-] 3% from fortified bush bean leaf tissue. Further experiments were conducted with bush bean plants maintained on RDX-containing hydroponic solutions. Hydroponic plants did not emit detectable amounts of [sup 14]CO[sub 2] or radiolabeled volatile organics. Analysis of the plant tissue indicated bioaccumulation of RDX in the aerial tissues of hydroponic plants exposed for either 1 or 7 d. Metabolism of RDX to polar metabolites was observed in plants exposed for 7 d.

  13. Growth changes of eighteen herbaceous angiosperms induced by Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in soil.

    PubMed

    Hagan, Frank L; Koeser, Andrew K; Dawson, Jeffrey O

    2016-01-01

    Study objectives were to describe and quantify growth responses (tolerance as shoot and root biomass accumulation) to soil-applied Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) treatments of eighteen terrestrial, herbaceous, angiospermous species and also; to determine how much of RDX, RDX transformation products, total N and RDX-derived N accumulated in the foliage. RDX altered growth of eighteen plant species or cultivars at levels of 100, 500, and 1,000 mg kg(-1)dry soil in a 75-d greenhouse study. Sixteen species or cultivars exhibited growth inhibition while two were stimulated in growth by RDX. A maximum amount of foliar RDX in a subset of three plant species was 36.0 mg per plant in Coronilla varia. Foliar concentrations of transformation products of RDX were low relative to RDX in the subset of three species. The proportion of RDX-N with respect to total N was constant, suggesting that foliar RDX transformation did not explain differences in tolerance. There was a δ (15)N shift towards that of synthetic RDX in foliage of the three species at a level of 1,000 mg kg(-1) RDX, proportional in magnitude to uptake of N from RDX and tolerance ranking.Reddened leaf margins for treated Sida spinosa indicate the potential of this species as a biosensor for RDX.

  14. Toxicologic and histopathologic response of the terrestrial salamander Plethodon cinereus to soil exposures of 1,3,5-trinitrohexahydro-1,3,5-triazine.

    PubMed

    Johnson, M S; Paulus, H I; Salice, C J; Checkai, R T; Simini, M

    2004-11-01

    Red-backed salamanders (Plethodon cinereus) were exposed to four different concentrations of 1,3,5-trinitrohexahydro-1,3,5-triazine (RDX) in soil under controlled laboratory conditions for 28 days. Wild-caught P. cinereus (N = 20/treatment) were exposed to target concentrations of 5,000, 1000, 100, 10, and 0 mg RDX/kg soil (dry wt) using a microcosm design. Animals were fed 5 to 10 uncontaminated mutant Drosophila flies every 3 days and monitored daily. Animals were weighed 1 day before being placed in treatment and weekly thereafter. RDX concentrations in soil were analytically determined after the compound was added and mixed at the beginning, the midpoint, and the end of exposure. RDX soil concentrations were relatively stable throughout the exposure period. Signs of overt toxicity were observed primarily in the highest exposure group. Salamanders exposed to 5,000 mg RDX/kg soil exhibited signs of neuromuscular effects (lethargy, gaping, hypersensitivity, tremors) and exhibited significant weight loss. A single moribund animal from this group lost >20% of its original body weight and was killed. Animals in this exposure group also lost weight relative to animals in other treatments. Histopathologic evaluations, including an evaluation of melanomacrophage parameters, indicated no strong treatment-related findings. This study provided information regarding the effects from subchronic dermal exposure of a terrestrial amphibian species to RDX in soil and provides a microcosm approach to the evaluation of toxicity of contaminants in soil to a terrestrial vertebrate.

  15. On the low pressure shock initiation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine based plastic bonded explosives

    NASA Astrophysics Data System (ADS)

    Vandersall, Kevin S.; Tarver, Craig M.; Garcia, Frank; Chidester, Steven K.

    2010-05-01

    In large explosive and propellant charges, relatively low shock pressures on the order of 1-2 GPa impacting large volumes and lasting tens of microseconds can cause shock initiation of detonation. The pressure buildup process requires several centimeters of shock propagation before shock to detonation transition occurs. In this paper, experimentally measured run distances to detonation for lower input shock pressures are shown to be much longer than predicted by extrapolation of high shock pressure data. Run distance to detonation and embedded manganin gauge pressure histories are measured using large diameter charges of six octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) based plastic bonded explosives (PBX's): PBX 9404; LX-04; LX-07; LX-10; PBX 9501; and EDC37. The embedded gauge records show that the lower shock pressures create fewer and less energetic "hot spot" reaction sites, which consume the surrounding explosive particles at reduced reaction rates and cause longer distances to detonation. The experimental data is analyzed using the ignition and growth reactive flow model of shock initiation in solid explosives. Using minimum values of the degrees of compression required to ignite hot spot reactions, the previously determined high shock pressure ignition and growth model parameters for the six explosives accurately simulate the much longer run distances to detonation and much slower growths of pressure behind the shock fronts measured during the shock initiation of HMX PBX's at several low shock pressures.

  16. RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) biodegradation in aquifer sediments under manganese-reducing conditions

    USGS Publications Warehouse

    Bradley, Paul M.; Dinicola, Richard S.

    2005-01-01

    A shallow, RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine)–contaminated aquifer at Naval Submarine Base Bangor has been characterized as predominantly manganese-reducing, anoxic with local pockets of oxic conditions. The potential contribution of microbial RDX degradation to localized decreases observed in aquifer RDX concentrations was assessed in sediment microcosms amended with [U-14C] RDX. Greater than 85% mineralization of14C-RDX to 14CO2 was observed in aquifer sediment microcosms under native, manganese-reducing, anoxic conditions. Significant increases in the mineralization of 14C-RDX to 14CO2 were observed in anoxic microcosms under NO3-amended or Mn(IV)-amended conditions. No evidence of 14C-RDX biodegradation was observed under oxic conditions. These results indicate that microbial degradation of RDX may contribute to natural attenuation of RDX in manganese-reducing aquifer systems.

  17. Anaerobic transformation of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) by ovine rumen microorganisms.

    PubMed

    Perumbakkam, Sudeep; Craig, A M

    2012-01-01

    Explosives such as octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) provide a challenge in terms of bioremediation. In the present study, sheep rumen was studied for its potential to detoxify HMX using analytical chemistry and molecular microbial ecology tools. Results indicated significant loss (p < 0.05) of HMX at 8 h post-incubation and complete disappearance of the parent molecule after 16 h. Qualitative LC-MS/MS analysis provided evidence for the formation of 1-NO-HMX and MEDINA metabolites. A total of 1006 16S rRNA-V3 clones were sequenced and the Classifier tool of the RDPII database was used to sort the sequences at their phylum level. Most sequences were associated with either the phylum Bacteroidetes or Firmicutes. Significant differences at the phylum level (p < 0.001) were found between 0 h and 8 h HMX treatments. Using LibCompare analysis, 8 h HMX treatment showed enrichment of clones (p < 0.01) belonging to the genus Prevotella. From these results, it could be concluded that members of the genus Prevotella are enriched in the rumen and are capable of detoxifying HMX.

  18. Synthesis, structural and computational characterization of 2-amino-3,5-diiodobenzoic acid and 2-amino-3,5-dibromobenzoic acid

    NASA Astrophysics Data System (ADS)

    Yıldırım, M. Hakkı; Paşaoğlu, Hümeyra; Odabaşoğlu, Hakkı Yasin; Odabaşoğlu, Mustafa; Yıldırım, Arzu Özek

    2015-07-01

    The benzoic acid compounds 2-amino-3,5-dibromobenzoic acid (2A35Br) and 2-amino-3,5-diiodobenzoic (2A35I) acid have been synthesized and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, UV-Vis spectroscopy and computational methods. Molecular geometry, intra- and inter-molecular interactions have been investigated by using X-ray diffraction technique. Fundamental vibrational bands of the title compounds were founded by FT-IR and UV-Vis method was used to obtain electronic bands. Geometry optimizations and the calculation of IR frequencies were performed both Gaussian type orbitals at Gaussian 09W and Slater type orbitals at ADF2009.01 software. The calculations are compatible with the experiment results. In addition, geometrical parameters, energies, HOMO-LUMO gaps and electrophilicity indexes have been calculated for thirty possible positional isomers of 2A35Br and 2A35I. Calculations show that 2A35Br and 2A35I isomers have the lowest energy, the narrowest HOMO-LUMO gap and the highest electrophilicity index values. Molecular electrostatic potential maps, Fukui indices, natural bond orbital analysis, thermodynamic parameters and non-linear optical properties of the 2A35Br and 2A35I were also investigated by theoretical calculations.

  19. Comparative neurotoxicity of two energetic compounds, hexanitrohexaazaisowurtzitane and hexahydro-1,3,5-trinitro-1,3,5-triazine, in the earthworm Eisenia fetida.

    PubMed

    Gong, Ping; Inouye, Laura S; Perkins, Edward J

    2007-05-01

    Hexanitrohexaazaisowurtzitane (CL-20) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX), both energetic compounds, share some degree of structural similarity. A noninvasive electrophysiological technique was employed to assess the impacts of acute sublethal exposures on impulse conduction in medial (MGF) and lateral (LGF) giant nerve fiber pathways of the earthworm Eisenia fetida and to evaluate the reversibility of neurotoxic effects. Earthworms were exposed to either 0.02 to 2.15 microg/cm2 of CL-20 or 0.04 to 5.35 microg/cm2 of RDX, for 1 to 14 d, on moistened filter paper. Conduction velocities of MGF and LGF were recorded on a digital oscilloscope before and after exposure. Results indicate that at exposure levels as low as 0.02 microg/cm2 of CL-20 or 0.21 microg/cm2 of RDX, worms exhibited physiological impacts such as retardation, stiffness, and body shrink. Both MGF and LGF conduction velocities were negatively correlated with increasing doses of CL-20 or RDX. However, such neurotoxic effects were alleviated or even eliminated within a few days after exposed worms were transferred to an uncontaminated environment, indicating that the neurotoxicity is reversible even after 6-d exposure. The CL-20 is more potent than RDX, which is consistent with previous studies on lethality, growth, and reproduction endpoints in soil oligochaetes.

  20. Density functional study of 1,3,5-trinitro-1,3,5-triazine molecular crystal with van der Waals interactions.

    PubMed

    Shimojo, Fuyuki; Wu, Zhongqing; Nakano, Aiichiro; Kalia, Rajiv K; Vashishta, Priya

    2010-03-01

    Volume dependence of the total energy and vibrational properties of crystalline l,3,5-trinitro-l,3,5-triazine (RDX) are calculated using the density functional theory (DFT). For this molecular crystal, properties calculated with a generalized gradient approximation to the exchange-correlation energy differ drastically from experimental values. This discrepancy arises from the inadequacy in treating weak van der Waals (vdW) interactions between molecules in the crystal, and an empirical vdW correction to DFT (DFT-D approach by Grimme) is shown to account for the dispersion effects accurately for the RDX crystal, while incurring little computational overhead. The nonempirical van der Waals density-functional (vdW-DF) method also provides an accurate description of the vdW corrections but with orders-of-magnitude more computation. We find that the vibrational properties of RDX are affected in a nontrivial manner by the vdW correction due to its dual role--reduction of the equilibrium volume and additional atomic forces.

  1. In Silico Alkaline Hydrolysis of Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine: Density Functional Theory Investigation.

    PubMed

    Sviatenko, Liudmyla K; Gorb, Leonid; Hill, Frances C; Leszczynska, Danuta; Shukla, Manoj K; Okovytyy, Sergiy I; Hovorun, Dmytro; Leszczynski, Jerzy

    2016-09-20

    HMX (octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine), an energetic material used in military applications, may be released to the environment during manufacturing, transportation, storage, training, and disposal. A detailed investigation of a possible mechanism of alkaline hydrolysis, as one of the most promising methods for HMX remediation, was performed by computational study at PCM(Pauling)/M06-2X/6-311++G(d,p) level. Obtained results suggest that HMX hydrolysis at pH 10 represents a highly exothermic multistep process involving initial deprotonation and nitrite elimination, hydroxide attachment accompanied by cycle cleavage, and further decomposition of cycle-opened intermediate to the products caused by a series of C-N bond ruptures, hydroxide attachments, and proton transfers. Computationally predicted products of HMX hydrolysis such as nitrite, 4-nitro-2,4-diazabutanal, formaldehyde, nitrous oxide, formate, and ammonia correspond to experimentally observed species. Based on computed reaction pathways for HMX decomposition by alkaline hydrolysis, the kinetics of the entire process was modeled. Very low efficiency of this reaction at pH 10 was observed. Computations predict significant increases (orders of magnitude) of the hydrolysis rate for hydrolysis reactions undertaken at pH 11, 12, and 13. PMID:27523798

  2. Dissolution and sorption of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) and 2,4,6-trinitrotoluene (TNT) residues from detonated mineral surfaces.

    PubMed

    Jaramillo, Ashley M; Douglas, Thomas A; Walsh, Marianne E; Trainor, Thomas P

    2011-08-01

    Composition B (Comp B) is a commonly used military formulation composed of the toxic explosive compounds 2,4,6-trinitrotoluene (TNT), and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX). Numerous studies of the temporal fate of explosive compounds in soils, surface water and laboratory batch reactors have been conducted. However, most of these investigations relied on the application of explosive compounds to the media via aqueous addition and thus these studies do not provide information on the real world loading of explosive residues during detonation events. To address this we investigated the dissolution and sorption of TNT and RDX from Comp B residues loaded to pure mineral phases through controlled detonation. Mineral phases included nontronite, vermiculite, biotite and Ottawa sand (quartz with minor calcite). High Performance Liquid Chromatography and Attenuated Total Reflectance Fourier Transform Infrared spectroscopy were used to investigate the dissolution and sorption of TNT and RDX residues loaded onto the mineral surfaces. Detonation resulted in heterogeneous loading of TNT and RDX onto the mineral surfaces. Explosive compound residues dissolved rapidly (within 9 h) in all samples but maximum concentrations for TNT and RDX were not consistent over time due to precipitation from solution, sorption onto mineral surfaces, and/or chemical reactions between explosive compounds and mineral surfaces. We provide a conceptual model of the physical and chemical processes governing the fate of explosive compound residues in soil minerals controlled by sorption-desorption processes. PMID:21601233

  3. Biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by a prospective consortium and its most effective isolate Serratia marcescens

    SciTech Connect

    Young, D.M.; Ogden, K.L.; Unkefer, P.J.

    1997-03-05

    The biotransformation of hexahydro-1,3,5-trinitro-1,3,5 triazine (RDX) has been observed in liquid culture by a consortium of bacteria found in horse manure. Five types of bacteria were found to predominate in the consortium and were isolated. The most effective of these isolates at transforming RDX was Serratia marcescens. The biotransformation of RDX by all of these bacteria was found to occur only in the anoxic stationary phase. The process of bacterial growth and RDX biotransformation was quantified for the purpose of developing a predictive type model. Cell growth was assumed to follow Monod kinetics. All of the aerobic and anoxid growth parameters were determined: {mu}{sub max}, K{sub s}, and Y{sub x/s}. RDX was found to competitively inhibit cell growth in both atmospheres. Degradation of RDX by Serratia marcescens was found to proceed through the stepwise reduction of the three nitro groups to nitroso groups. Each of these reductions was found to be first order in both component and cell concentrations. The degradation rate constant for the first step in this reduction process by the consortium was 0.022 L/g cells {center_dot} h compared to 0.033 L/g cells {center_dot} h for the most efficient isolate.

  4. The effect of p,p'-dichlorodiphenyltrichloroethane on levels of guanosine 3',5'-cyclic monophosphate and adenosine 3',5'-cyclic monophosphate in two species of insects.

    PubMed

    Bodnaryk, R P

    1976-11-01

    Within 1 h after topical application of a convulsive dose (4 mug per fly, 47 mg/kg) of p,p'-dichlorodiphenyltrichloroethane (DDT) to the adult male of Sarcophaga bullata Parker, guanosine 3',5'-cyclic monophosphate (cyclic GMP) levels rose by 71.5% (P less than 0.05) in the head, 159.5% (P less than 0.01) in the thorax, and 23.4% (P greater than 0.05) in the abdomen compared to controls. Adenosine 3',5'-cyclic monophosphate (cyclic AMP) levels were not significantly affected by the DDT treatment. A convulsive dose (100 mug per larva, 250 mg/kg) of DDT applied to larvae of Mamestra configurata Wlk. caused the whole body level of cyclic GMP to rise by 81.6% (P less than 0.01) after 1 h, and by 95.9% (P less than 0.01) after 3 h. Levels of cyclic AMP were not affected. A hypothesis is advanced suggesting that an abnormally high rate of discharge of acetylcholine (and in the later stages of poisoning, its actual accumulation) at central cholinergic synapses causes cyclic GMP levels to rise, perhaps in post-synaptic cells. The elevated cyclic GMP-cyclic AMP ratio found in DDT-poisoned insects may be of fundamental importance in the complex sequence of events leading to tremor, hyperexcitability, paralysis, and death.

  5. Characterization of polymorphic states in energetic samples of 1,3,5-trinitro-1,3,5-triazine (RDX) fabricated using drop-on-demand inkjet technology.

    PubMed

    Emmons, Erik D; Farrell, Mikella E; Holthoff, Ellen L; Tripathi, Ashish; Green, Norman; Moon, Raphael P; Guicheteau, Jason A; Christesen, Steven D; Pellegrino, Paul M; Fountain, Augustus W

    2012-06-01

    The United States Army and the first responder community are evaluating optical detection systems for the trace detection of hazardous energetic materials. Fielded detection systems must be evaluated with the appropriate material concentrations to accurately identify the residue in theater. Trace levels of energetic materials have been observed in mutable polymorphic phases and, therefore, the systems being evaluated must be able to detect and accurately identify variant sample phases observed in spectral data. In this work, we report on the novel application of drop-on-demand technology for the fabrication of standardized trace 1,3,5-trinitro-1,3,5-triazine (RDX) samples. The drop-on-demand sample fabrication technique is compared both visually and spectrally to the more commonly used drop-and-dry technique. As the drop-on-demand technique allows for the fabrication of trace level hazard materials, concerted efforts focused on characterization of the polymorphic phase changes observed with low concentrations of RDX commonly used in drop-on-demand processing. This information is important when evaluating optical detection technologies using samples prepared with a drop-on-demand inkjet system, as the technology may be "trained" to detect the common bulk α phase of the explosive based on its spectral features but fall short in positively detecting a trace quantity of RDX (β-phase). We report the polymorphic shifts observed between α- and β-phases of this energetic material and discuss the conditions leading to the favoring of one phase over the other.

  6. Effects of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) exposure on reproduction and hatchling development in Northern bobwhite quail.

    PubMed

    Brunjes, Kristina J; Severt, Scott A; Liu, Jun; Pan, Xiaoping; Brausch, John; Cox, Stephen A; Cobb, George P; McMurry, Scott T; Kendall, Ronald J; Smith, Philip N

    2007-04-15

    Adult Northern bobwhite quail (Colinus virginianus) were exposed via food to octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), an energetic compound found in soils at military training installations. Depuration of HMX into eggs was examined in an initial study, and effects on egg production, hatching, growth, development, and survival of chicks were examined in a follow-up study. HMX was readily and rapidly transferred from female quail into eggs. Marked weight loss was observed in quail exposed to 125 and 250 mg/kg HMX in food, likely due to reductions in food intake rather than a toxic mechanism. In the second study, significant alterations in body mass occurred among quail at concentrations >52.5 +/- 9.3 mg/kg but not at 12.3 +/- 1.1 mg/kg in food. Treatment-related reductions in food consumption and decreases in egg laying rates were observed. No HMX-related effects were found in chick growth or survival. Quail inhabiting HMX-contaminated sites could possibly be exposed to HMX and therefore deposition of HMX into eggs is also possible. However, results of these studies further suggest that the potential for reproductive toxicity of HMX to birds is low.

  7. Chronic toxicity of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in soil determined using the earthworm (Eisenia andrei) reproduction test.

    PubMed

    Robidoux, P Y; Hawari, J; Thiboutot, S; Ampleman, G; Sunahara, G I

    2001-01-01

    The sublethal and chronic effects of the environmental contaminant and explosive octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) in artificial soil were assessed using the earthworm (Eisenia andrei). Based on various reproduction parameters (total and hatched number of cocoons, number of juveniles and their biomass), fecundity was reduced at the different concentrations of HMX tested (from 280.0 +/- 12.3 to 2502.9 +/- 230.0 mg kg-1 dry soil) in spiked artificial soil (LOEC: 280.0 +/- 12.3 mg kg-1 dry soil). The growth of adult E. andrei was also reduced at the different concentrations tested, though no mortality occurred, even at the highest tested concentrations. The number of juveniles produced was correlated with the number of total and hatched cocoons, and the biomass of juveniles was correlated with the number of cocoons. Pooled results of these and earlier studies on explosives (TNT, RDX) using the E. andrei reproduction test confirm that effects of HMX on cocoon production are indicative of some reproductive consequences (number of juvenile and their biomass), whereas adult growth, in general, does not correlate strongly with change in reproduction capacity.

  8. Performance of mesophilic anaerobic granules for removal of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) from aqueous solution.

    PubMed

    An, Chun-jiang; He, Yan-ling; Huang, Guo-he; Liu, Yong-hong

    2010-07-15

    The performance of mesophilic anaerobic granules to degrade octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) was investigated under various conditions. The results of batch experiments showed that anaerobic granules were capable of removing HMX from aqueous solution with high efficiency. Both biotic and abiotic mechanisms contributed to the removal of HMX by anaerobic granules under mesophilic conditions. Adsorption appeared to play a significant role in the abiotic process. Furthermore, HMX could be biodegraded by anaerobic granules as the sole substrate. After 16 days of incubation, 99.04% and 96.42% of total HMX could be removed by 1g VSS/L acclimated and unacclimated granules, respectively. Vancomycin, an inhibitor of acetogenic bacteria, caused a significant inhibition of HMX biotransformation, while 2-bromoethanesulfonic acid, an inhibitor of methanogenic bacteria, only resulted in a slight decrease of metabolic activity. The presence of the glucose, as a suitable electron donor and carbon source, was found to enhance the degradation of HMX by anaerobic granules. Our study showed that sulfate had little adverse effects on biotransformation of HMX by anaerobic granules. However, nitrate had significant inhibitory effect on the extent of HMX removal especially in the initial period. This study offered good prospects of using high-rate anaerobic technology in the treatment of munition wastewater.

  9. Food avoidance behavior to dietary octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) exposure in the northern bobwhite (Colinusvirginianus).

    PubMed

    Johnson, Mark S; Gogal, Robert M; Larsen, Calvert T

    2005-08-13

    High-melting explosive (HMX; octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) is a widely utilized explosive component of munitions used by the military. Consequently, production and use through testing and training at military installations has resulted in deposition of HMX in soil. Since these areas are often used by birds, the oral toxicity of HMX exposure to northern bobwhite (Colinus virginianus) was evaluated. Attempts to determine the acute lethal dose were unsuccessful. Initially, 8 birds (1 male/1 female per dose group) were orally dosed at levels ranging from 125 to 2125 mg HMX/kg body weight. A single death at the midrange resulted in subsequent trials of oral doses up to 10,760 mg/kg body weight. Only a single death occurred at 7173 mg/kg. A subsequent 28-d feeding study was then conducted to evaluate the potential for toxicity resulting from repetitive oral exposures. Northern bobwhite were exposed to concentrations of HMX in feed of either 10000, 1000, 100, or 0 mg/kg. These exposures resulted in a clear concentration-related reduction in feed consumption and body mass. Reductions in egg production in females were correlated with changes in body mass and feed consumption. Other physiological indicators were consistent with a considerable reduction in feed intake. These results suggest that HMX concentration is responsible for intense feed aversion behavior and thus not likely a factor that would appreciably contribute to risk for wild birds at military ranges.

  10. Cloning, Sequencing, and Characterization of the Hexahydro-1,3,5-Trinitro-1,3,5-Triazine Degradation Gene Cluster from Rhodococcus rhodochrous

    PubMed Central

    Seth-Smith, Helena M. B.; Rosser, Susan J.; Basran, Amrik; Travis, Emma R.; Dabbs, Eric R.; Nicklin, Steve; Bruce, Neil C.

    2002-01-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a high explosive which presents an environmental hazard as a major land and groundwater contaminant. Rhodococcus rhodochrous strain 11Y was isolated from explosive contaminated land and is capable of degrading RDX when provided as the sole source of nitrogen for growth. Products of RDX degradation in resting-cell incubations were analyzed and found to include nitrite, formaldehyde, and formate. No ammonium was excreted into the medium, and no dead-end metabolites were observed. The gene responsible for the degradation of RDX in strain 11Y is a constitutively expressed cytochrome P450-like gene, xplA, which is found in a gene cluster with an adrenodoxin reductase homologue, xplB. The cytochrome P450 also has a flavodoxin domain at the N terminus. This study is the first to present a gene which has been identified as being responsible for RDX biodegradation. The mechanism of action of XplA on RDX is thought to involve initial denitration followed by spontaneous ring cleavage and mineralization. PMID:12324318

  11. Electron shuttle-mediated biotransformation of hexahydro-1,3,5-trinitro-1,3,5-triazine adsorbed to granular activated carbon.

    PubMed

    Millerick, Kayleigh; Drew, Scott R; Finneran, Kevin T

    2013-08-01

    Granular activated carbon (GAC) effectively removes hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) from groundwater but generates RDX-laden GAC that must be disposed of or regenerated. Batch reactors containing GAC to which RDX was preadsorbed were used in experiments to test the potential for adsorbed RDX reduction and daughter product formation using (i) chemically reduced anthrahydroquinone-2,6-disulfonate (AH2QDS), (ii) resting Geobacter metallireducens strain GS-15, and (iii) a combined system containing AQDS and GS-15. Approximately 97.0% of the adsorbed RDX was transformed in each of these experimental systems by 90 h. Chemically reduced AQDS (AH2QDS) transformed 99.2% of adsorbed RDX; formaldehyde was produced rapidly and was stoichiometric (3 mol HCHO per mol RDX). Geobacter metallireducens also reduced RDX with and without AQDS present. This is the first study to demonstrate biological transformation of RDX adsorbed to GAC. Formaldehyde increased and then decreased in biological systems, suggesting a previously unreported capacity for G. metallireducens to oxidize formaldehyde, which was confirmed with resting cell suspensions. These data suggest the masses of GAC waste currently produced by activated carbon at RDX remediation sites can be minimized, decreasing the carbon footprint of the treatment technology. Alternatively, this strategy may be used to develop a Bio-GAC system for ex situ RDX treatment.

  12. Towards ten-watt-level 3-5 µm Raman lasers using tellurite fiber.

    PubMed

    Zhu, Gongwen; Geng, Lixiang; Zhu, Xiushan; Li, Li; Chen, Qian; Norwood, R A; Manzur, T; Peyghambarian, N

    2015-03-23

    Raman lasers based on mid-infrared fibers operating at 3-5 µm atmospheric transparency window are attractive sources for several applications. Compared to fluoride and chalcogenide fibers, tellurite fibers are more advantageous for high power Raman fiber laser sources at 3-5 µm because of their broader Raman gain bandwidth, much larger Raman shift and better physical and chemical properties. Here we report on our simulations for the development of 10-watt-level 3-5 µm Raman lasers using tellurite fibers as the nonlinear gain medium and readily available continuous-wave (cw) and Q-switched erbium-doped fluoride fiber lasers at 2.8 µm as the pump sources. Our results show that a watt-level or even ten-watt-level fiber laser source in the 3-5 µm atmospheric transparency window can be achieved by utilizing the 1st- and 2nd-order Raman scattering in the tellurite fiber. The presented numerical study provides valuable guidance for future 3-5 um Raman fiber laser development. PMID:25837094

  13. Synthesis and Thermal Decomposition Mechanism of the Energetic Compound 3,5-Dinitro-4-nitroxypyrazole

    NASA Astrophysics Data System (ADS)

    Feng, Xiao-Qin; Cao, Duan-Lin; Cui, Jian-Lan

    2016-07-01

    A novel energetic material, 3,5-dinitro-4-nitroxypyrazole (DNNP), was synthesized via nitration and nucleophilic substitution reaction using 4-chloropyrazole as raw material. The structure of DNNP was characterized by Fourier transform infrared (FTIR), nuclear magnetic resonance (NMR), and elemental analysis. Its detonation properties were calculated and compared with those of other commonly used energetic compounds. The thermal decomposition mechanism of DNNP was studied by means of thermogravimetry and differential scanning calorimetry coupled with a mass spectrometry (DSC-MS). The results show that the detonation properties of DNNP were better than those of TNT and comparable to those of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). In addition, the thermal decomposition mechanism of DNNP was supposed. Initially, the O-NO2 bond was broken, thereby producing a nitropyrazole oxygen radical. Subsequently, the nitropyrazole oxygen radical was decomposed by free radical cleavage of nitro or isomerized to nitritepyrazole and subsequently decomposed by free radical cleavage of the nitroso group. Finally, pyrazole ring fission occurred and produced N2, NO, N2O, and CO2.

  14. Induction of phosphodiesterase by cyclic adenosine 3':5'-monophosphate in differentiating Dictyostelium discoideum amoebae.

    PubMed

    Klein, C

    1975-09-25

    Cyclic adenosine 3':5'-monophosphate added to the starvation media of Dictyostelium discoideum amoebae induces both intracellular and extracellular phosphodiesterase activities of these cells. The induced enzyme activity appears several hours earlier than that in starved cells which have not been induced with cyclic nucleotide. In both cases, the appearance of enzyme is inhibited by cycloheximide, and actinomycin D, and daunomycin. The KmS for the extracellular enzyme(s) of nucleotide-induced and uninduced control cells are identical. The induction of enzyme activity seems specific for cyclic adenosine 3':5'-monophosphate since cyclic guanosine 3':5'-monophosphate, as well as other nucleotides, have no effect. No differences in the activity or excretion of either N-acetylglucosaminidase or the inhibitory of the extracellular phosphodiesterase are observed between cyclic adenosine 3':5'-monophosphate-induced and control cells. A direct activation of phosphodiesterase by cyclic adenosine 3':5'-monophosphate can be excluded, since the addition of this nucleotide to cell lysates has no effect on the enzyme activity. PMID:170256

  15. [Study on Raman spectrum of nanophase anatase].

    PubMed

    Li, Y; Duan, Y; Li, W

    2000-10-01

    The nanophase anatase of different sizes (2-40 nm) were synthesized with chemical precipitation method. Nanophase anatase (2-40 nm), anatase (micron) and natural anatase were investigated by Raman spectrum. The spectra indicate: when the crystalline particles sizes decreased, obvious Raman shifts towards higher frequencies were observed and the intensity of Raman scattering decreased markedly. The shift towards higher frequencies reached max (10 cm-1) at 143 cm-1 comparing 2 nm anatase and natural anatase; when the crystalline particles sizes decreased; the shifts at 515 and 637 cm-1 towards higher frequencies reached max, but while the crystalline particles sizes became smaller, the shifts reached towards lower frequencies; There was no obvious shift at 396 cm-1 with the decreasing of the crystalline particle sizes. These reflect the complexity of nanophase materials structure, that may be caused by flexibility distortion of crystal.

  16. Measurements of Diffuse Sky Emission Components in High Galactic Latitudes at 3.5 and 4.9 um Using Dirbe and WISE Data

    NASA Astrophysics Data System (ADS)

    Sano, K.; Kawara, K.; Matsuura, S.; Kataza, H.; Arai, T.; Matsuoka, Y.

    2016-02-01

    Using all-sky maps obtained from the Cosmic Background Explorer/Diffuse Infrared Background Experiment (DIRBE) at 3.5 and 4.9 μm, we present a reanalysis of diffuse sky emissions such as zodiacal light (ZL), diffuse Galactic light (DGL), integrated starlight (ISL), and isotropic residual emission including the extragalactic background light (EBL). Our new analysis, which includes an improved estimate of ISL using the Wide-field Infrared Survey Explorer data, enabled us to find the DGL signal in a direct linear correlation between diffuse near-infrared and 100 μm emission at high Galactic latitudes (| b| \\gt 35^\\circ ). At 3.5 μm, the high-latitude DGL result is comparable to the low-latitude value derived from the previous DIRBE analysis. In comparison with models of the DGL spectrum assuming a size distribution of dust grains composed of amorphous silicate, graphite, and polycyclic aromatic hydrocarbon (PAH), the measured DGL values at 3.5 and 4.9 μm constrain the mass fraction of PAH particles in the total dust species to be more than ˜2%. This was consistent with the results of Spitzer/IRAC toward the lower Galactic latitude regions. The derived residual emission of 8.9 ± 3.4 nWm-2 sr-1 at 3.5 μm is marginally consistent with the level of integrated galaxy light and the EBL constraints from the γ-ray observations. The residual emission at 4.9 μm is not significantly detected due to the large uncertainty in the ZL subtraction, the same as in previous studies. Combined with our reanalysis of the DIRBE data at 1.25 and 2.2 μm, the residual emission in the near-infrared exhibits the Rayleigh-Jeans spectrum.

  17. Feasibility studies of the growth of 3-5 compounds of boron by MOCVD

    NASA Technical Reports Server (NTRS)

    Manasevit, H. M.

    1988-01-01

    Boron-arsenic and boron-phosphorus films have been grown on Si sapphire and silicon-on-sapphire (SOS) by pyrolyzing Group 3 alkyls of boron, i.e., trimethylborane (TMB) and triethylborane (TEB), in the presence of AsH3 and PH3, respectively, in an H2 atmosphere. No evidence for reaction between the alkyls and the hydrides on mixing at room temperature was found. However, the films were predominantly amorphous. The film growth rate was found to depend on the concentration of alkyl boron compound and was essentially constant when TEB and AsH3 were pyrolyzed over the temperature range 550 C to 900 C. The films were found to contain mainly carbon impurities (the amount varying with growth temperature), some oxygen, and were highly stressed and bowed on Si substrates, with some crazing evident in thin (2 micron) B-P and thick (5 micron) B-As films. The carbon level was generally higher in films grown using TEB as the boron source. Films grown from PH3 and TMB showed a higher carbon content than those grown from AsH3 and TMB. Based on their B/As and B/P ratios, films with nominal compositions B sub12-16 As2 and B sub1.1-1.3 P were grown using TMB as the boron source.

  18. Low-dosage micronized 17 beta-estradiol prevents bone loss in postmenopausal women

    NASA Technical Reports Server (NTRS)

    Ettinger, B.; Genant, H. K.; Steiger, P.; Madvig, P.

    1992-01-01

    With the use of a double-blind, randomized, dose-ranging design, we tested during an 18-month period the degree of protection against postmenopausal bone loss afforded by micronized 17 beta-estradiol in dosages of 0.5, 1.0, and 2.0 mg. All subjects received supplementation to ensure a minimum of 1500 mg calcium daily. Fifty-one subjects completed at least 1 year of follow-up bone density measurements by quantitative computed tomography and by single- and dual-photon absorptiometry. In the placebo group spinal trabecular bone density decreased 4.9% annually (p less than 0.001), whereas in those taking micronized 17 beta-estradiol bone density tended to increase (annual increases of 0.3% in the 0.5 mg micronized 17 beta-estradiol group, 1.8% in the 1.0 mg micronized 17 beta-estradiol group, and 2.5% in the 2.0 mg micronized 17 beta-estradiol group). After completing the double-blind phase, 41 subjects completed an additional 18 months of follow-up while taking 1.0 mg micronized 17 beta-estradiol. During this time one third of the subjects were randomly assigned to discontinue calcium supplements. Among those who previously received placebo, trabecular bone density increased 4.3% annually, whereas among those who had used micronized 17 beta-estradiol, trabecular bone density response was inversely related to the dosage previously used. Additionally and independently, the level of calcium intake showed a statistically significant correlation with the change in spinal trabecular bone density (r = 0.37, p = 0.02). We conclude that micronized 17 beta-estradiol has a continuous skeletal dose-response effect in the range of 0.5 to 2.0 mg and that calcium intake positively modifies the skeletal response to 1.0 mg micronized 17 beta-estradiol.

  19. High-Resolution Spectroscopy of the νb{16} Band of 1,3,5-TRIOXANE

    NASA Astrophysics Data System (ADS)

    Gibson, Bradley M.; Koeppen, Nicole; McCall, Benjamin J.

    2014-06-01

    1,3,5-trioxane, often used as a solid fuel or source of formaldehyde, is a symmetric top of the C3v group. Although the microwave and low-resolution vibrational spectra have been studied extensively, only the νb{17} band near 1072 wn has been observed with rotational resolution. Here, we will present our studies of trioxane vapor from 1140-1220 wn, covering the νb{16} band at a resolution of approximately 30 MHz. Solid trioxane was heated, and the resulting vapor was entrained in a continuous supersonic expansion of argon. Continuous-wave cavity ringdown spectroscopy was then performed using a frequency-stabilized external cavity quantum cascade laser (EC-QCL) as the light source. In addition to providing new ro-vibrational transition frequencies of trioxane, the present work serves to validate our newly-developed EC-QCL spectrometer and will be used to evaluate the cooling performance of the sheath-flow supercritical fluid expansion source currently under development. Oka, T., Tsuchiya, K., Iwata, S., and Morino, Y. Microwave Spectrum of s-Trioxane. Bull. Chem. Soc. Jpn. 37 (1964), 4-7. Stair, A.T. Jr. and Nielsen, J. Rud. Vibrational Spectra of sym-Trioxane. J. Chem. Phys. 27 (1957), 402-407. Henninot, J-F., Bolvin, H., Demaison, J., and Lemoine, B. The Infrared Spectrum of Trioxane in a Supersonic Slit Jet. J. Mol. Spect. 152 (1992), 62-68. Gibson, B.M., Stewart, J.T., and McCall, B.J., contribution TJ14, presented at the 68th International Symposium on Molecular Spectroscopy, Columbus, OH, USA, 2013.

  20. Laser Acoustic Microstructure Analysis at the Micron and Nanometer Length Scale

    SciTech Connect

    Telschow, Kenneth Louis; Hurley, David Howard

    2002-05-01

    Laser acoustic approaches to investigating the interaction of elastic waves with microstructure in materials is presented that probe both the micron and nanometer length scales. At the micron length scale, a full-field imaging approach is described that provides quantitative measurement of amplitude and phase of the out-of-plane acoustical motion at GHz frequencies. Specific lateral acoustic modes can be identified in addition to the primary thickness mode with spatial resolution sufficient to image wavelengths as small as 4.5 microns.

  1. 8- to 13-micron spectrophotometry of Comet IRAS-Araki-Alcock

    NASA Technical Reports Server (NTRS)

    Feierberg, M. A.; Witteborn, F. C.; Johnson, J. R.; Campins, H.

    1984-01-01

    Spectrophotometry between 8.0 and 13.0 microns at 2 percent spectral resolution is presented for areas in and near the nuclear condensation of Comet IRAS-Araki-Alcock (1983d) on May 11 and 12, 1983. All the spectra can be fit very well by blackbody curves, and no 10-micron silicate emissions are seen. The temperature structure of the coma suggests the presence of small (radii less than 5 microns) dust particles within 150 km of the nucleus and larger ones further out. The change in the spatial distribution of the infrared flux between the two nights suggests that an outburst may have occurred sometime on May 11.

  2. Sensitivity of 2,6-Diamino-3, 5-Dinitropyrazine-1-Oxide

    SciTech Connect

    Tarver, C M; Urtiew, P A; Tran, T D

    2005-01-20

    The thermal and shock sensitivities of plastic bonded explosive formations based on 2,6-diamino-3,5-dinitropyrazine-1-oxide (commonly called LLM-105 for Lawrence Livermore Molecule No.105) are reported. The One Dimensional Time to Explosion (ODTX) apparatus was used to generate times to thermal explosion at various initial temperatures. A four-reaction chemical decomposition model was developed to calculate the time to thermal explosion versus inverse temperature curve. Three embedded manganin pressure gauge experiments were fired at different initial pressures to measure the pressure buildup and the distance required for transition to detonation. An Ignition and Growth reactive model was calibrated to this shock initiation data. LLM-105 exhibited thermal and shock sensitivities intermediate between those of triaminotrinitrobenzene (TATB) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazine (HMX).

  3. Poly[(μ(5)-3,5-dinitro-benzoato)rubidium].

    PubMed

    Miao, Yanqing; Zhang, Xiaoqing; Liu, Chunye

    2011-07-01

    The asymmetric unit of the title compound, [Rb(C(7)H(3)N(2)O(6))](n), comprises an Rb cation and a 3,5-dinitro-benzoate anion. The Rb cation is eight-coordinated by O atoms from five 3,5-dinitro-benzoate anions. On the other hand, each 3,5-dinitro-benzoate anion links five Rb cations with the carboxyl-ate groups as μ(3)-bridging. The metal atom is firstly linked by the carboxyl-ate groups into a chain along the c-axis direction, which is further linked by bonds between the Rb and nitro O atoms, giving a three-dimensional framework. PMID:21836829

  4. Synthesis and structural characterization of 3,5-dinitro-1,2,4-triazolates.

    PubMed

    Haiges, R; Bélanger-Chabot, G; Kaplan, S M; Christe, K O

    2015-02-21

    Salts of 3,5-dinitro-1H-1,2,4-triazole, a building block for energetic materials, have been prepared and fully characterized. Most of the studied salts exhibit high thermal stability and very low shock and friction sensitivities. 3,5-Dinitro-1,2,4-triazolates with the nitrogen-rich ammonium, guanidinium, aminoguanidinium, and aminotetrazolium cations are energetic and have potential for energetic material applications. Salts containing alkali, alkali earth metal, and silver cations exhibit coloured emissions upon combustion while salts with large organic cations such as PPh4(+) and (Ph3P)2N(+) are highly insensitive and can be easily crystallized.

  5. Access to Pyrazolidin-3,5-diones through Anodic N-N Bond Formation.

    PubMed

    Gieshoff, Tile; Schollmeyer, Dieter; Waldvogel, Siegfried R

    2016-08-01

    Pyrazolidin-3,5-diones are important motifs in heterocyclic chemistry and are of high interest for pharmaceutical applications. In classic organic synthesis, the hydrazinic moiety is installed through condensation using the corresponding hydrazine building blocks. However, most N,N'-diaryl hydrazines are toxic and require upstream preparation owing to their low commercial availability. We present an alternative and sustainable synthetic approach to pyrazolidin-3,5-diones that employs readily accessible dianilides as precursors, which are anodically converted to furnish the N-N bond. The electroconversion is conducted in a simple undivided cell under constant-current conditions. PMID:27392318

  6. Accelerating Spectrum Sharing Technologies

    SciTech Connect

    Juan D. Deaton; Lynda L. Brighton; Rangam Subramanian; Hussein Moradi; Jose Loera

    2013-09-01

    Spectrum sharing potentially holds the promise of solving the emerging spectrum crisis. However, technology innovators face the conundrum of developing spectrum sharing technologies without the ability to experiment and test with real incumbent systems. Interference with operational incumbents can prevent critical services, and the cost of deploying and operating an incumbent system can be prohibitive. Thus, the lack of incumbent systems and frequency authorization for technology incubation and demonstration has stymied spectrum sharing research. To this end, industry, academia, and regulators all require a test facility for validating hypotheses and demonstrating functionality without affecting operational incumbent systems. This article proposes a four-phase program supported by our spectrum accountability architecture. We propose that our comprehensive experimentation and testing approach for technology incubation and demonstration will accelerate the development of spectrum sharing technologies.

  7. Accumulation of hexahydro-1,3,5-trinitro-1,3,5-triazine by the earthworm Eisenia andrei in a sandy loam soil.

    PubMed

    Sarrazin, Manon; Dodard, Sabine G; Savard, Kathleen; Lachance, Bernard; Robidoux, Pierre Y; Kuperman, Roman G; Hawari, Jalal; Ampleman, Guy; Thiboutot, Sonia; Sunahara, Geoffrey I

    2009-10-01

    The heterocyclic polynitramine hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a highly energetic compound found as a soil contaminant at some defense installations. Although RDX is not lethal to soil invertebrates at concentrations up to 10,000 mg/kg, it decreases earthworm cocoon formation and juvenile production at environmentally relevant concentrations found at contaminated sites. Very little is known about the uptake of RDX in earthworms and the potential risks for food-chain transfer of RDX in the environment. Toxicokinetic studies were conducted to quantify the bioaccumulation factors (BAFs) using adult earthworms (Eisenia andrei) exposed for up to 14 d to sublethal concentrations of nonlabeled RDX or [14C]RDX in a Sassafras sandy loam soil. High-performance liquid chromatography of acetonitrile extracts of tissue and soil samples indicated that nonlabeled RDX can be accumulated by the earthworm in a concentration- and time-dependent manner. The BAF, expressed as the earthworm tissue to soil concentration ratio, decreased from 6.7 to 0.1 when the nominal soil RDX concentrations were increased from 1 to 10,000 mg/kg. Tissue concentrations were comparable in earthworms exposed to nonlabeled RDX or [14C]RDX. The RDX bioaccumulation also was estimated using the kinetically derived model (BAFK), based on the ratio of the uptake to elimination rate constants. The established BAFK of 3.6 for [14C]RDX uptake was consistent with the results for nonlabeled RDX. Radioactivity also was present in the tissue residues of [14C]RDX-exposed earthworms following acetonitrile extraction, suggesting the formation of nonextractable [14C]RDX metabolites associated with tissue macromolecules. These findings demonstrated a net accumulation of RDX in the earthworm and the potential for food-chain transfer of RDX to higher-trophic-level receptors.

  8. The little-studied cluster Berkeley 90. I. LS III +46 11: a very massive O3.5 If* + O3.5 If* binary

    NASA Astrophysics Data System (ADS)

    Maíz Apellániz, J.; Negueruela, I.; Barbá, R. H.; Walborn, N. R.; Pellerin, A.; Simón-Díaz, S.; Sota, A.; Marco, A.; Alonso-Santiago, J.; Sanchez Bermudez, J.; Gamen, R. C.; Lorenzo, J.

    2015-07-01

    Context. It appears that most (if not all) massive stars are born in multiple systems. At the same time, the most massive binaries are hard to find owing to their low numbers throughout the Galaxy and the implied large distances and extinctions. Aims: We want to study LS III +46 11, identified in this paper as a very massive binary; another nearby massive system, LS III +46 12; and the surrounding stellar cluster, Berkeley 90. Methods: Most of the data used in this paper are multi-epoch high S/N optical spectra, although we also use Lucky Imaging and archival photometry. The spectra are reduced with dedicated pipelines and processed with our own software, such as a spectroscopic-orbit code, CHORIZOS, and MGB. Results: LS III +46 11 is identified as a new very early O-type spectroscopic binary [O3.5 If* + O3.5 If*] and LS III +46 12 as another early O-type system [O4.5 V((f))]. We measure a 97.2-day period for LS III +46 11 and derive minimum masses of 38.80 ± 0.83 M⊙ and 35.60 ± 0.77 M⊙ for its two stars. We measure the extinction to both stars, estimate the distance, search for optical companions, and study the surrounding cluster. In doing so, a variable extinction is found as well as discrepant results for the distance. We discuss possible explanations and suggest that LS III +46 12 may be a hidden binary system where the companion is currently undetected.

  9. Toxic effects of oral hexahydro-1,3,5-trinitro-1,3,5-triazine in the western fence lizard (Sceloporus occidentalis).

    PubMed

    McFarland, Craig A; Quinn, Michael J; Bazar, Matthew A; Talent, Larry G; Johnson, Mark S

    2009-05-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) has been widely used as an explosive in munition formulations, resulting in contamination of wildlife habitat on military installations. To estimate health effects for reptilian species, acute, subacute, and subchronic oral toxicity studies were conducted using the Western fence lizard (Sceloporus occidentalis). Estimated oral median lethal doses were 72 (95% confidence interval [CI], 49-106) mg/kg body weight (slope, 3.754) for males and 88 (95% CI, 65-119) mg/kg (slope, 4.525) for females. Toxicity from RDX suggested the neurological system as the critical target tissue. A 14-d subacute study followed with males dosed orally with RDX (corn oil) at 0, 10, 20, 25, 30, 45, and 60 mg/kg/d. Signs of toxicity frequently included a characteristic body posture. A significant dose-survival relationship was seen over the range of doses, with a significant decrease in survival at 20 mg/kg/d. Males in the 60-d subchronic study were dosed at 0, 1, 2.5, 5, 8, and 11 mg/kg/d, and signs of toxicity included lethargy, cachexia, and anorexia. Survival was decreased at 8 and 11 mg/kg/d. Reduced growth rate and food consumption occurred at 5 mg/kg/d. Brain tissue was assayed for RDX when seizures were observed at a residue concentration of at least 18 microg/g. No abnormalities were observed in the hematologic indices, whereas plasma proteins were reduced. Hepatic enlargement and decreased testes mass occurred at 8 and 11 mg/kg/d. Plasma testosterone concentrations, sperm counts, and motility measures were variable for all treatment levels. Based on survival, growth rate, food intake, and testes to brain weight ratios, these data suggest a lowest-observed-adverse effect level of 5 mg/kg/d and a no-observed-adverse effect level of 2.5 mg/kg/d. PMID:19102580

  10. Identification of hexahydro-1,3,5-trinitro-1,3,5-triazine-degrading microorganisms via 15N-stable isotope probing.

    PubMed

    Roh, Hyungkeun; Yu, Chang-Ping; Fuller, Mark E; Chu, Kung-Hui

    2009-04-01

    This study reported the application of 15N-stable isotope probing (SIP) to identify active hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX)-utilizing microorganisms in groundwater microcosms. Fifteen 16S rRNA gene sequences were derived from the 15N-DNA fraction (contributed from active microorganisms capable of using RDX as a nitrogen source) of microcosms receiving cheese whey. The 16S rRNA gene sequences belonged to Actinobacteria (two clones), alpha-Proteobacteria (seven clones), and gamma-Proteobacteria (six clones). Except for five sequences with high similarity to two known RDX degraders (Enterobacter cloacae and Pseudomonas fluorescens I-C), our results suggested that phylogenetically diverse microorganisms were capable of using RDX as a nitrogen source. Six sequences of the xplA gene (a known RDX-degrading catabolic gene) were detected from the 15N-DNA fraction. The xplA gene sequences were 96-99% similar to the xplA gene of Rhodococcus sp. DN22(a known RDX utilizer), suggesting that other RDX utilizers might contain xplA-like genes. Twenty-five 16S rRNA gene sequences recovered from the unenriched, RDX-contaminated groundwater clustered differently from those obtained from the 15N-DNA fraction of the cheese-whey-amended microcosm. Our results suggested that active RDX utilizers can be stimulated by nutrient source additions even if they are present at low densities, and that use of 15N-SIP can identifythese functional members of the microbial community.

  11. Evaluation of Biostimulation and Bioaugmentation To Stimulate Hexahydro-1,3,5-trinitro-1,3,5,-triazine Degradation in an Aerobic Groundwater Aquifer.

    PubMed

    Michalsen, Mandy M; King, Aaron S; Rule, Rebecca A; Fuller, Mark E; Hatzinger, Paul B; Condee, Charles W; Crocker, Fiona H; Indest, Karl J; Jung, Carina M; Istok, Jack D

    2016-07-19

    Hexahydro-1,3,5-trinitro-1,3,5,-triazine (RDX) is a toxic and mobile groundwater contaminant common to military sites. This study compared in situ RDX degradation rates following bioaugmentation with Gordonia sp. strain KTR9 (henceforth KTR9) to rates under biostimulation conditions in an RDX-contaminated aquifer in Umatilla, OR. Bioaugmentation was achieved by injecting site groundwater (6000 L) amended with KTR9 cells (10(8) cells mL(-1)) and low carbon substrate concentrations (<1 mM fructose) into site wells. Biostimulation (no added cells) was performed by injecting groundwater amended with low (<1 mM fructose) or high (>15 mM fructose) carbon substrate concentrations in an effort to stimulate aerobic or anaerobic microbial activity, respectively. Single-well push-pull tests were conducted to measure RDX degradation rates for each treatment. Average rate coefficients were 1.2 day(-1) for bioaugmentation and 0.7 day(-1) for high carbon biostimulation; rate coefficients for low carbon biostimulation were not significantly different from zero (p values ≥0.060). Our results suggest that bioaugmentation with KTR9 is a feasible strategy for in situ biodegradation of RDX and, at this site, is capable of achieving RDX concentration reductions comparable to those obtained by high carbon biostimulation while requiring ~97% less fructose. Bioaugmentation has potential to minimize substrate quantities and associated costs, as well as secondary groundwater quality impacts associated with anaerobic biostimulation processes (e.g., hydrogen sulfide, methane production) during full-scale RDX remediation.

  12. Analysis of the xplAB-Containing Gene Cluster Involved in the Bacterial Degradation of the Explosive Hexahydro-1,3,5-Trinitro-1,3,5-Triazine

    PubMed Central

    Chong, Chun Shiong; Sabir, Dana Khdr; Lorenz, Astrid; Bontemps, Cyril; Andeer, Peter; Stahl, David A.; Strand, Stuart E.; Rylott, Elizabeth L.

    2014-01-01

    Repeated use of the explosive compound hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) on military land has resulted in significant soil and groundwater pollution. Rates of degradation of RDX in the environment are low, and accumulated RDX, which the U.S. Environmental Protection Agency has determined is a possible human carcinogen, is now threatening drinking water supplies. RDX-degrading microorganisms have been isolated from RDX-contaminated land; however, despite the presence of these species in contaminated soils, RDX pollution persists. To further understand this problem, we studied RDX-degrading species belonging to four different genera (Rhodococcus, Microbacterium, Gordonia, and Williamsia) isolated from geographically distinct locations and established that the xplA and xplB (xplAB) genes, which encode a cytochrome P450 and a flavodoxin redox partner, respectively, are nearly identical in all these species. Together, the xplAB system catalyzes the reductive denitration of RDX and subsequent ring cleavage under aerobic and anaerobic conditions. In addition to xplAB, the Rhodococcus species studied here share a 14-kb region flanking xplAB; thus, it appears likely that the RDX-metabolizing ability was transferred as a genomic island within a transposable element. The conservation and transfer of xplAB-flanking genes suggest a role in RDX metabolism. We therefore independently knocked out genes within this cluster in the RDX-degrading species Rhodococcus rhodochrous 11Y. Analysis of the resulting mutants revealed that XplA is essential for RDX degradation and that XplB is not the sole contributor of reducing equivalents to XplA. While XplA expression is induced under nitrogen-limiting conditions and further enhanced by the presence of RDX, MarR is not regulated by RDX. PMID:25128343

  13. Evaluation of Biostimulation and Bioaugmentation To Stimulate Hexahydro-1,3,5-trinitro-1,3,5,-triazine Degradation in an Aerobic Groundwater Aquifer.

    PubMed

    Michalsen, Mandy M; King, Aaron S; Rule, Rebecca A; Fuller, Mark E; Hatzinger, Paul B; Condee, Charles W; Crocker, Fiona H; Indest, Karl J; Jung, Carina M; Istok, Jack D

    2016-07-19

    Hexahydro-1,3,5-trinitro-1,3,5,-triazine (RDX) is a toxic and mobile groundwater contaminant common to military sites. This study compared in situ RDX degradation rates following bioaugmentation with Gordonia sp. strain KTR9 (henceforth KTR9) to rates under biostimulation conditions in an RDX-contaminated aquifer in Umatilla, OR. Bioaugmentation was achieved by injecting site groundwater (6000 L) amended with KTR9 cells (10(8) cells mL(-1)) and low carbon substrate concentrations (<1 mM fructose) into site wells. Biostimulation (no added cells) was performed by injecting groundwater amended with low (<1 mM fructose) or high (>15 mM fructose) carbon substrate concentrations in an effort to stimulate aerobic or anaerobic microbial activity, respectively. Single-well push-pull tests were conducted to measure RDX degradation rates for each treatment. Average rate coefficients were 1.2 day(-1) for bioaugmentation and 0.7 day(-1) for high carbon biostimulation; rate coefficients for low carbon biostimulation were not significantly different from zero (p values ≥0.060). Our results suggest that bioaugmentation with KTR9 is a feasible strategy for in situ biodegradation of RDX and, at this site, is capable of achieving RDX concentration reductions comparable to those obtained by high carbon biostimulation while requiring ~97% less fructose. Bioaugmentation has potential to minimize substrate quantities and associated costs, as well as secondary groundwater quality impacts associated with anaerobic biostimulation processes (e.g., hydrogen sulfide, methane production) during full-scale RDX remediation. PMID:27301804

  14. Analysis of the key intermediates of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) in groundwater: occurrence, stability and preservation.

    PubMed

    Paquet, Louise; Monteil-Rivera, Fanny; Hatzinger, Paul B; Fuller, Mark E; Hawari, Jalal

    2011-08-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a widely used explosive that is present in soils at a number of military sites, including training and testing ranges. Because of its relatively weak adsorption to soil, RDX frequently migrates through the unsaturated zone and causes groundwater contamination. In the environment, RDX can transform to produce mono-, di-, and tri-nitroso derivatives (MNX, DNX, and TNX) and the ring cleavage products methylenedinitramine (MEDINA) and 4-nitro-2,4-diazabutanal (NDAB). The present study was undertaken to analyze RDX and its products in groundwater samples taken from various US military sites. The stability of some of the common transformation intermediates of RDX, including the nitroso derivatives, NDAB and MEDINA, under typical conditions in a groundwater aquifer is not well understood, and appropriate preservation methods for these compounds have not been established. Therefore, we studied the inherent stability of these compounds in deionized water and in groundwater, and evaluated various preservation techniques, including adjustment of pH, temperature, and salinity. NDAB and nitroso derivatives were stable under typical ambient environmental conditions, but MEDINA was highly unstable. The addition of sea salts (10% w/v) was found to stabilize MEDINA when the samples were stored at 4 °C. Using appropriate preservation techniques, we detected nitroso derivatives and NDAB, but no MEDINA, at some of the sites investigated. Stabilizing RDX intermediate products in field samples to allow detection is important because the presence of any of these chemicals can indicate past contamination by RDX and provide insight into the occurrence of in situ natural attenuation. PMID:21734991

  15. Analysis of the key intermediates of RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) in groundwater: occurrence, stability and preservation.

    PubMed

    Paquet, Louise; Monteil-Rivera, Fanny; Hatzinger, Paul B; Fuller, Mark E; Hawari, Jalal

    2011-08-01

    Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) is a widely used explosive that is present in soils at a number of military sites, including training and testing ranges. Because of its relatively weak adsorption to soil, RDX frequently migrates through the unsaturated zone and causes groundwater contamination. In the environment, RDX can transform to produce mono-, di-, and tri-nitroso derivatives (MNX, DNX, and TNX) and the ring cleavage products methylenedinitramine (MEDINA) and 4-nitro-2,4-diazabutanal (NDAB). The present study was undertaken to analyze RDX and its products in groundwater samples taken from various US military sites. The stability of some of the common transformation intermediates of RDX, including the nitroso derivatives, NDAB and MEDINA, under typical conditions in a groundwater aquifer is not well understood, and appropriate preservation methods for these compounds have not been established. Therefore, we studied the inherent stability of these compounds in deionized water and in groundwater, and evaluated various preservation techniques, including adjustment of pH, temperature, and salinity. NDAB and nitroso derivatives were stable under typical ambient environmental conditions, but MEDINA was highly unstable. The addition of sea salts (10% w/v) was found to stabilize MEDINA when the samples were stored at 4 °C. Using appropriate preservation techniques, we detected nitroso derivatives and NDAB, but no MEDINA, at some of the sites investigated. Stabilizing RDX intermediate products in field samples to allow detection is important because the presence of any of these chemicals can indicate past contamination by RDX and provide insight into the occurrence of in situ natural attenuation.

  16. Flame spread through cracks of PBX 9501 (a composite octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine-based explosive)

    NASA Astrophysics Data System (ADS)

    Berghout, H. Laine; Son, Steven F.; Hill, Larry G.; Asay, Blaine W.

    2006-06-01

    Recent experiments involving combustion of PBX 9501 [a plastic-bonded high explosive composed of 95% octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) by weight in a plasticized, estane-based binder] under confined conditions underscore the importance of cracks and flaws in reaction violence. The presence of a small void space or alternative escape path for combustion gases at the closed end of a crack drastically alters combustion violence. In the case of a true closed-ended crack, where gases can only escape by exiting the open end of the crack, luminous combustion spreads through the closed crack at relatively low rates in the range of a few meters per second, regardless of the pressure external to the slot. Hence, external pressure determines whether reaction can progress into the restricted dimensions of the slot, but it does not necessarily determine the dynamics of the flame's progress in the slot. When an alternative combustion-gas escape path is available at the closed end of the slot, luminous combustion spreads through the crack at hundreds of meters per second. Additionally, combustion in cracks of confined PBX 9501 materials exhibits oscillatory behavior with a frequency of about 1000 Hz for the experimental configuration used. This oscillatory behavior resembles combustion instabilities observed in rocket motors and may arise from similar processes. We also report on preliminary experiments involving 19.1 cm long slots in confined PBX 9501, which have produced very high flame-propagation rates of 1500 m/s.

  17. Adsorption-desorption of 2,4,6-trinitrotoluene and hexahydro-1,3,5-trinitro-1,3,5-triazine in soils

    SciTech Connect

    Xue, S.K.; Selim, H.M.; Iskandar, I.K.

    1995-11-01

    This study studied the adsorption-desorption behavior of TNT (2, 4, 6-trinitrotoluene) and RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) in a bentonite/sand reference material (Swy-1 montmorillonite clay mixed with acid-washed sand) and two selected soils (Norwood and Kolin). Release of TNT,RDX, and other compounds from a contaminated soil obtained from the Louisiana Army Ammunition Plant (AAP) site was also investigated. The kinetics of TNT and RDX retention were measured using batch methods for a range of input concentrations. For RDX, the adsorption isotherms were distinctly linear. The TNT adsorption isotherm for bentonite/sand mixture appeared linear and was described equally well using linear, Freundlich, Langmuir, and a modified Langmuir model. For the Norwood and Kolin soils, TNT adsorption isotherms exhibited distinct nonlinearity and the Freundlich model provided the best fit. As indicated by the K{sub d} values, TNT exhibited stronger retention or affinity to all soils and the bentonite/sand mixture than for RDX. The RDX retention data indicated little time-dependent behavior. The TNT retention data indicated a continued decrease in TNT concentration with time in the Norwood and Kolin soils. This was possibly caused by the formation and subsequent adsorption of transformation products because transformation products, such as amino nitro toluene compounds, were identified during batch experiments. For the bentonite/sand mixture, TNT retention was rapid initially and reached apparent equilibrium within 1 day. Unlike Kolin and Norwood soils, there was no hysteretic behavior of TNT adsorption-desorption by the bentonite/sand mixture and a mass balance suggested fully reversible retention mechanisms. 15 refs., 13 figs., 2 tabs.

  18. Transport of 2,4,6-trinitrotoluene and hexahydro-1,3,5-trinitro-1,3,5-triazine in soils

    SciTech Connect

    Selim, H.M.; Xue, S.K.; Iskandar, I.K.

    1995-11-01

    This study investigated the fate and transport of explosives in soils. Transport experiments were conducted to describe the mobility of 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) in a SWy-1 reference clay (bentonite mixed with sand) and two selected soils (Norwood and Kolin). Miscible displacement experiments in packed soil columns under steady flow were used. For the bentonite/sand column, TNT was highly mobile and fully reversible when methanol was used as the background solution. In contrast the TNT pulse was strongly retarded with as much as 50% of that applied remaining within the bentonite/sand, Norwood, or Kolin columns. Products of the transformation of TNT to 4-Am-DNT and other compound were identified in the effluent solution. A 7-day flow interruption during the TNT pulse application resulted in decreased TNT levels in the effluent solution. This decrease corresponded to a sudden increase in the 4-Am-DNT concentration in the effluent. For RDX only limited retention was observed. These findings are consistent with results from adsorption-desorption batch experiments. The TNT and RDX transport results were successfully described by a nonlinear multireaction and transport model (MRTM), which accounted for equilibrium and kinetic (reversible and irreversible) retention mechanisms. However, efforts to describe RDX transport were more successful than efforts to describe TNT when independently determined (batch) parameters were used. The mobility of TNT, RDX, and other compounds from a contaminated soil obtained from a Louisiana Army Ammunition Plant (AAP) site was also investigated. A gradual release and subsequent movement of various contaminants, including HMX, TNT, RDX, TNG, 2-Am-DNT, and 4-Am-DNT, was observed. The leaching patterns were consistent with results from uncontaminated Kolin soil columns and reflected the affinity of contaminants during leaching in the AAP soil. 18 refs., 9 figs., 1 tab.

  19. Accumulation and effects of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) exposure in the green anole (Anolis carolinensis).

    PubMed

    McMurry, S T; Jones, L E; Smith, P N; Cobb, G P; Anderson, T A; Lovern, M B; Cox, S; Pan, X

    2012-03-01

    Environmental contamination by energetic compounds is an increasing international concern, although little is known of their accumulation in and affect on wildlife. Reptiles are often good models for contaminants studies due to natural history traits that increase their potential for exposure. We report a study to assess accumulation and effects of octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX, High Melting Explosive) in green anoles (Anolis carolinensis). Acute oral toxicity (LD(50)) was estimated to exceed 2000 mg/kg body weight in adult male and female anoles using a standard up-and-down method. Accumulation of HMX was assessed in adult females via dietary exposure and into eggs by two routes (directly from the soil and via maternal transfer). HMX readily accumulated into adult females in a dose-dependent manner and into eggs following both exposure pathways. However, total HMX in soil-exposed eggs was up to 40-times greater than those exposed via maternal transfer. Although there was a suggestion of an HMX-induced reduction in body weight in adult females, overall there were no effects observed over the 12 week exposure period. The only significant effect on eggs was a 50% reduction in hatching success for eggs exposed to 2000 mg/kg HMX in the soil during incubation. Growth and survival of hatchlings was not affected by HMX exposure. Our results demonstrate that HMX accumulates through the food chain and into eggs from the soil, but likely poses minimal threat to lizards except to hatching success in eggs incubated in soils with HMX levels near maximum environmental concentrations.

  20. Transformation and Release of Micronized Cu used as a Wood Preservative in Treated Wood in Wetland Soil

    EPA Science Inventory

    Micronized Cu (µ-Cu) is used as a wood preservative, replacing toxic Chromated Copper Arsenates. Micronized Cu is Malachite [Cu2CO3(OH)2] that has been milled to micron/submicron particles, many with diameters less than 100 nm, and then mixed with quat or azol biocides. I...

  1. Quantum Spread Spectrum Communication

    SciTech Connect

    Humble, Travis S

    2011-01-01

    We show that communication of single-photon quantum states in a multi-user environment is improved by using spread spectrum communication techniques. We describe a framework for spreading, transmitting, despreading, and detecting single-photon spectral states that mimics conventional spread spectrum techniques. We show in the cases of inadvertent detection, unintentional interference, and multi-user management, that quantum spread spectrum communications may minimize receiver errors by managing quantum channel access.

  2. Controlling Persister and Biofilm Cells of Gram-Negative Bacteria with a New 1,3,5-Triazine Derivative.

    PubMed

    Bahar, Ali Adem; Liu, Zhigang; Garafalo, Meagan; Kallenbach, Neville; Ren, Dacheng

    2015-01-01

    Infections caused by multidrug-resistant bacteria have been on the rise. This important issue presents a great challenge to the healthcare system and creates an urgent need for alternative therapeutic agents. As a potential solution to this problem, antimicrobial peptides (AMPs) have attracted increasing attention due to their broad spectrum of targeted microbes. However, most AMPs are expensive to synthesize, have relatively high cytotoxicity to mammalian cells, and are susceptible to proteolytic degradation. In order to overcome these limitations, novel synthetic AMPs are desired. Using 1,3,5-triazine (TN) as a template, several combinatorial libraries with varying cationic charge and lipophilicity were designed and screened by the Kallenbach lab. From this screening, TN-5 was identified as a potent lead. In the present study, this compound was tested for its antimicrobial activities on Escherichia coli and Pseudomonas aeruginosa. In addition to regular planktonic cells, the effects on biofilms and persister cells (metabolically inactive and antibiotic tolerant subpopulation) were also investigated. TN-5 was found to have a minimum inhibitory concentration (MIC) of 12.8 μM for both species and kill regular planktonic cells of both species dose dependently. TN-5 is also effective against persister cells of both E. coli and P. aeruginosa. The killing of biofilm cells of the mucoid P. aeruginosa PDO300 was enhanced by alginate lyase. PMID:26473884

  3. The photospheric magnetic field of the dM3.5e flare star AD Leonis

    NASA Technical Reports Server (NTRS)

    Saar, S. H.; Linsky, J. L.

    1985-01-01

    A high-resolution infrared spectrum of the dM3.5e flare star AD Leo, obtained with the Kitt Peak 4 m Fourier Transform Spectrometer, clearly shows the presence of strong magnetic fields. Five absorption lines in the 4400-4600 per cm region have been modeled, and it is inferred that 73 percent + or - 6 percent of the surface of AD Leo is covered by active regions outside of dark spots containing a mean field strength of 3800 + or - 260 G. If these active regions are brighter than the quiet photosphere, the surface filling factor will be somewhat smaller. Since simultaneous H-alpha observations exhibited no evidence of flares, the observations probably represent the quiescent magnetic flux level. The inferred field strength is consistent with equipartition of magnetic and thermal pressures in the photosphere and is similar to values derived using the scaling laws of Golub. The large observed filling factor is consistent with efficient dynamo generation of magnetic flux in this rapidly rotating star.

  4. Fourier transform and Vernier spectroscopy using an optical frequency comb at 3-5.4  μm.

    PubMed

    Khodabakhsh, Amir; Ramaiah-Badarla, Venkata; Rutkowski, Lucile; Johansson, Alexandra C; Lee, Kevin F; Jiang, Jie; Mohr, Christian; Fermann, Martin E; Foltynowicz, Aleksandra

    2016-06-01

    We present a versatile mid-infrared frequency comb spectroscopy system based on a doubly resonant optical parametric oscillator tunable in the 3-5.4 μm range and two detection methods: a Fourier transform spectrometer (FTS) and a continuous-filtering Vernier spectrometer (CF-VS). Using the FTS with a multipass cell, we measure high precision broadband absorption spectra of CH4 at 3.3 μm and NO at 5.25 μm, the latter for the first time with comb spectroscopy, and we detect atmospheric species (CH4, CO, CO2, and H2O) in air in the signal and idler ranges. Multiline fitting yields minimum detectable concentrations of 10-20  ppb Hz-1/2 for CH4, NO, and CO. For the first time in the mid-infrared, we perform CF-VS using an enhancement cavity, a grating, and a single detector, and we measure the absorption spectrum of CH4 and H2O in ambient air at ∼3.3  μm, reaching a 40 ppb concentration detection limit for CH4 in 2 ms.

  5. Vibrational spectra of 3,5-diamino-6-chloro-N-(diaminomethylene) pyrazine-2-carboxamide: Combined experimental and theoretical studies

    NASA Astrophysics Data System (ADS)

    Sakthivel, S.; Alagesan, T.; Al-Saadi, Abdulaziz A.; Renuga, S.; Muthu, S.

    2014-06-01

    In this work, the vibrational spectral analysis of 3,5-diamino-6-chloro-N-(diaminomethylene)pyrazine-2-carboxamide(3DCNDPC) was carried out using FT-Raman and FT-IR spectroscopy in the range 4000-50 cm-1 and 4000-500 cm-1 respectively. The experimental spectra were recorded in the solid phase. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) B3LYP with the standard basis set 6-311++G(d,p). The optimized geometric parameters (bond lengths and bond angles) were compared with experimental values. Normal co-ordinate calculations were performed with the DFT force field corrected by a recommended set of scaling factors yielding fairly good agreement between observed and calculated frequencies. Simulation of infrared and Raman spectra utilizing the results of these calculations led to excellent overall agreement with the observed spectral patterns. The complete assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. The stability of the molecule arising from hyper conjugative interactions and the charge delocalization has been analyzed by using Natural Bond Orbital (NBO) analysis. UV-Vis spectrum of the compound was recorded. The calculated HOMO and LUMO energies show that chemical activity of the molecule.

  6. Vibrational spectra of 3,5-diamino-6-chloro-N-(diaminomethylene) pyrazine-2-carboxamide: combined experimental and theoretical studies.

    PubMed

    Sakthivel, S; Alagesan, T; Al-Saadi, Abdulaziz A; Renuga, S; Muthu, S

    2014-06-01

    In this work, the vibrational spectral analysis of 3,5-diamino-6-chloro-N-(diaminomethylene)pyrazine-2-carboxamide(3DCNDPC) was carried out using FT-Raman and FT-IR spectroscopy in the range 4000-50cm(-1) and 4000-500cm(-1) respectively. The experimental spectra were recorded in the solid phase. The fundamental vibrational frequencies and intensity of vibrational bands were evaluated using density functional theory (DFT) B3LYP with the standard basis set 6-311++G(d,p). The optimized geometric parameters (bond lengths and bond angles) were compared with experimental values. Normal co-ordinate calculations were performed with the DFT force field corrected by a recommended set of scaling factors yielding fairly good agreement between observed and calculated frequencies. Simulation of infrared and Raman spectra utilizing the results of these calculations led to excellent overall agreement with the observed spectral patterns. The complete assignments were performed on the basis of the potential energy distribution (PED) of the vibrational modes, calculated with scaled quantum mechanics (SQM) method. The stability of the molecule arising from hyper conjugative interactions and the charge delocalization has been analyzed by using Natural Bond Orbital (NBO) analysis. UV-Vis spectrum of the compound was recorded. The calculated HOMO and LUMO energies show that chemical activity of the molecule. PMID:24632230

  7. 2-Micron Laser Transmitter for Coherent CO2 DIAL Measurement

    NASA Technical Reports Server (NTRS)

    Singh, Upendra N.; Bai, Yingxin; Yu, Jirong

    2009-01-01

    Carbon dioxide (CO2) has been recognized as one of the most important greenhouse gases. It is essential for the study of global warming to accurately measure the CO2 concentration in the atmosphere and continuously record its variation. A high repetition rate, highly efficient, Q-switched 2-micron laser system as the transmitter of a coherent differential absorption lidar for CO2 measurement has been developed in NASA Langley Research Center. This laser system is capable of making a vertical profiling of CO2 from ground and column measurement of CO2 from air and space-borne platform. The transmitter is a master-slave laser system. The master laser operates in a single frequency, either on-line or off-line of a selected CO2 absorption line. The slave laser is a Q-switched ring-cavity Ho:YLF laser which is pumped by a Tm:fiber laser. The repetition rate can be adjusted from a few hundred Hz to 10 kHz. The injection seeding success rate is from 99.4% to 99.95%. For 1 kHz operation, the output pulse energy is 5.5mJ with the pulse length of 50 ns. The optical-to-optical efficiency is 39% when the pump power is 14.5W. A Ho:YLF laser operating in the range of 2.05 micrometers can be tuned over several characteristic lines of CO2 absorption. Experimentally, a diode pumped Ho:Tm:YLF laser has been successfully used as the transmitter of coherent differential absorption lidar for the measurement of CO2 with a repetition rate of 5 Hz and pulse energy of 75 mJ. For coherent detection, high repetition rate is required for speckle averaging to obtain highly precise measurements. However, a diode pumped Ho:Tm:YLF laser can not operate in high repetition rate due to the large heat loading and up-conversion. A Tm:fiber laser pumped Ho:YLF laser with low heat loading can operate in high repetition rate. A theoretical model has been established to simulate the performance of Tm:fiber laser pumped Ho:YLF lasers. For continuous wave (CW) operation, high pump intensity with small beam

  8. Autism spectrum disorder

    MedlinePlus

    Autism; Autistic disorder; Asperger syndrome; Childhood disintegrative disorder; Pervasive developmental disorder ... to better diagnosis and newer definitions of ASD. Autism spectrum disorder now includes syndromes that used to ...

  9. Ionospheric wave spectrum measurements

    NASA Technical Reports Server (NTRS)

    Harker, K. J.; Ilic, D. B.; Crawford, F. W.

    1979-01-01

    The local spectrum S(k, omega) of either potential or electron-density fluctuations can be used to determine macroscopic-plasma characteristics such as the local density and temperature, transport coefficients, and drift current. This local spectrum can be determined by measuring the cross-power spectrum. The paper examines the practicality of using the cross-power spectrum analyzer on the Space Shuttle to measure ionospheric parameters. Particular attention is given to investigating the integration time required to measure the cross-power spectral density to a desired accuracy.

  10. Absorption features in the 5-8 micron spectra of protostars

    NASA Technical Reports Server (NTRS)

    Tielens, A. G. G. M.; Allamandola, L. J.; Bregman, J.; Goebel, J.; Witteborn, F. C.; Dhendecourt, L. B.

    1984-01-01

    High signal-to-noise ratio spectra in the range of 5-8 microns of four sources embedded in molecular clouds are examined using low-temperature laboratory measurements of the 5-8-micron spectra of simple molecules and their mixtures. The absorption, apparent in all four sources, is characterized by highly distinct features ranging from two relatively narrow bands at 6.0 and 6.8 microns in W33A to a broad, shallow, and partially structured feature extending from 5.2 to 7.8 microns in Mon R2-IRS2, BN, and NGC2264. The first feature (W33A) is explained by the OH bending mode in H2O and the CH deformation modes in saturated hydrocarbons; while the second feature (Mon R2-IRS2-type) is explained by the presence of a mixture of saturated and unsaturated hydrocarbons possibly containing strongly electronegative groups.

  11. A Master-Oscillator-Power-Amplifier 2-micron Laser Using Fiber Phase-conjugate Mirror

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Bai, Yingxin; Shkunov, V.; Rockwell, D.; Betin, A.; Wang, J.; Petros, M.; Petzar, Paul; Trieu, Bo

    2007-01-01

    For the first time, a 2-micron master-oscillator-power-amplifier laser using a fiber based phase conjugation mirror has been demonstrated. The beam quality improvement and 56% of the PCM reflectivity have been achieved.

  12. Bench-scale testing of a micronized magnetite, fine-coal cleaning process

    SciTech Connect

    Suardini, P.J.

    1995-11-01

    Custom Coals, International has installed and is presently testing a 500 lb/hr. micronized-magnetite, fine-coal cleaning circuit at PETC`s Process Research Facility (PRF). The cost-shared project was awarded as part of the Coal Preparation Program`s, High Efficiency Preparation Subprogram. The project includes design, construction, testing, and decommissioning of a fully-integrated, bench-scale circuit, complete with feed coal classification to remove the minus 30 micron slimes, dense medium cycloning of the 300 by 30 micron feed coal using a nominal minus 10 micron size magnetite medium, and medium recovery using drain and rinse screens and various stages and types of magnetic separators. This paper describes the project circuit and goals, including a description of the current project status and the sources of coal and magnetite which are being tested.

  13. Taking Another Look at the 3-Micron Absorption Band on Asteroids

    NASA Technical Reports Server (NTRS)

    Howell, E. S.; Rivkin, A. S.; Cohen, B. A.

    2002-01-01

    Improved 3 micron spectra show that band depths have been underestimated. Using a revised continuum, the asteroid and meteorite spectra match better. Additional information is contained in the original extended abstract.

  14. 2-Micron Pulsed Direct Detection IPDA Lidar for Atmospheric CO2 Measurement

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Petros, Mulugeta; Refaat, Tamer; Reithmaier, Karl; Remus, Ruben; Singh, Upendra; Johnson, Will; Boyer, Charlie; Fay, James; Johnston, Susan; Murchison, Luke

    2014-01-01

    A 2-micron high energy, pulsed Integrated Path Differential Absorption (IPDA) lidar has been developed for atmospheric CO2 measurements. Development of this lidar heavily leverages the 2-micron laser technologies developed in LaRC over the last decade. The high pulse energy, direct detection lidar operating at CO2 2-micron absorption band provides an alternate approach to measure CO2 concentrations. This new 2-micron pulsed IPDA lidar has been flown in spring of this year for total ten flights with 27 flight hours. It is able to make measurements of the total amount of atmospheric CO2 from the aircraft to the ground or cloud. It is expected to provide high-precision measurement capability by unambiguously eliminating contamination from aerosols and clouds that can bias the IPDA measurement.

  15. Preparation of multiparticulate systems for oral delivery of a micronized or nanosized poorly soluble drug.

    PubMed

    Cerea, Matteo; Pattarino, Franco; Foglio Bonda, Andrea; Palugan, Luca; Segale, Lorena; Vecchio, Carlo

    2016-09-01

    The purpose of the present work was to prepare multiparticulate drug delivery systems for oral administration of a poorly soluble drug such as itraconazole. Multiparticulate systems were prepared by extrusion/spheronization technique using a mix of crospovidone, low viscosity hypromellose, microcrystalline cellulose, micronized drug and water. In order to improve the release performance of the multiparticulate systems, the micronized drug was suspended in water with polysorbate 20 and nanonized by a high-pressure homogenization. The suspension of drug nanoparticles was then spray-dried for enabling an easy handling of the drug and for preventing the over-wetting of the powders during extrusion/spheronization processing. Both multiparticulate units prepared with micronized or nanonized drug showed acceptable disintegrating properties. The nanosizing of micronized drug powder provided a significant improvement of drug dissolution rates of the multiparticulates.

  16. Formation of micron and submicron structures on a zirconium oxide surface exposed to nanosecond laser radiation

    SciTech Connect

    Ganin, D V; Mikolutskiy, S I; Khomich, V Yu; Yamshchikov, V A; Tokarev, V N; Shmakov, V A

    2014-04-28

    Possibility of forming quasi-periodic structures of micron and submicron dimensions on a surface of zirconium dioxide under the action of eximer ArF laser radiation is shown experimentally and theoretically. (interaction of laser radiation with matter)

  17. Preparation of multiparticulate systems for oral delivery of a micronized or nanosized poorly soluble drug.

    PubMed

    Cerea, Matteo; Pattarino, Franco; Foglio Bonda, Andrea; Palugan, Luca; Segale, Lorena; Vecchio, Carlo

    2016-09-01

    The purpose of the present work was to prepare multiparticulate drug delivery systems for oral administration of a poorly soluble drug such as itraconazole. Multiparticulate systems were prepared by extrusion/spheronization technique using a mix of crospovidone, low viscosity hypromellose, microcrystalline cellulose, micronized drug and water. In order to improve the release performance of the multiparticulate systems, the micronized drug was suspended in water with polysorbate 20 and nanonized by a high-pressure homogenization. The suspension of drug nanoparticles was then spray-dried for enabling an easy handling of the drug and for preventing the over-wetting of the powders during extrusion/spheronization processing. Both multiparticulate units prepared with micronized or nanonized drug showed acceptable disintegrating properties. The nanosizing of micronized drug powder provided a significant improvement of drug dissolution rates of the multiparticulates. PMID:26786555

  18. FOURTEEN-DAY TOXICITY STUDY OF 1,3,5-TRINITROBENZENE IN FISCHER 344 RATS

    EPA Science Inventory

    Toxic effects of 1,3,5-trinitrobenzene (TNB) in male and female rats were evaluated by feeding powdered certified laboratory chow diet supplemented with varied concentrations of TNB (0,50,200,400,800 and 1200 mg kg-1 diet) for 14 days. Food intake by female rats in 400,800 and 12...

  19. DETERMINATION OF 3,5,6-TRICHLORO-2-PYRIDINOL (TCP) BY ELISA

    EPA Science Inventory

    A sensitive, competitive enzyme-linked immunosorbent assay (ELISA) for 3,5,6-trichloro-2pyridinol (TCP) has been developed to quantitate parts per billion (ppb) amounts of the analyte in urine. TCP is a major metabolite and environmental degradation product of the insecticide c...

  20. Evaluation of GALAXY Classroom Science for Grades 3-5. Final Report. Executive Summary.

    ERIC Educational Resources Information Center

    Guth, Gloria J. A.; Austin, Susan; DeLong, Bo; Pasta, David J.; Block, Clifford

    The GALAXY Classroom is a package of integrated curricular and instructional approaches, supported by the first U.S. interactive satellite communications network designed to facilitate the introduction of innovative curricula to improve student learning in elementary schools. GALAXY Classroom Science for grades 3-5 features the organization of…

  1. A Multiple-Data Analysis of the 3.5-Year Development of EFL Student Writers

    ERIC Educational Resources Information Center

    Sasaki, Miyuki

    2004-01-01

    The present study investigated the changes in Japanese students English writing behaviors over a 3.5-year period using multiple data sources including written texts, videotaped writing behaviors, and stimulated-recall protocols. Data from student interviews supplemented the analyses. Because 6 (henceforth, English as a second language [ESL]…

  2. Regioselective Glycosylation of 3-, 5-, 6-, and 7-Hydroxyflavones by Cultured Plant Cells.

    PubMed

    Shimoda, Kei; Kubota, Naoji; Uesugi, Daisuke; Fujitaka, Yuuya; Okada, Shouta; Tanigawa, Masato; Hamada, Hiroki

    2015-06-01

    Regioselective glycosylation of 3-, 5-, 6-, and 7-hydroxyflavones was investigated using cultured plant cells of Eucalyptus perriniana and Phytolacca americana as biocatalysts. 3- and 7-Hydroxyflavones were practically glycosylated into the corresponding β-D-glucosides by E. perriniana and P. americana.

  3. No Time for Tea (Grade Level: Elementary Grades, 3-5)

    ERIC Educational Resources Information Center

    Social Education, 2005

    2005-01-01

    Designed for Grades 3-5, this lesson plan aims to let the students learn how the Constitution of the United States provided the framework for the country's democratic form of government. Students will learn how the Constitution provided for representation within the government. A short story about the Boston Tea Party gives the background related…

  4. Spectral Properties of Clouds from 2.5 microto 3.5 micro.

    PubMed

    Blau, H H; Espinola, R P

    1968-10-01

    On the basis of simple models, the observed spectral reflectance properties of sunlit high altitude clouds in the 2.5-3.5-micro region are related, in decreasing order of importance, to the scattering properties of water droplets and ice crystals, absorption by ir active gases entrained within the cloud, and atmospheric transmission over the sun-cloud path.

  5. Smart Spending and Saving: Personal Finance Economics 3-5. Teacher Resource Manual. EconomicsAmerica.

    ERIC Educational Resources Information Center

    Haskell, Diana C.; Haskell, Douglas A.

    This book is designed to help students in grades 3-5 make better decisions as spenders, savers, borrowers, and managers of money. The learning experiences focus on personal finance and money management. The 10 lessons are divided into 4 units focusing on children making spending decisions, saving decisions, borrowing decisions, and money…

  6. Supporting English Language Learners in Math Class, Grades 3-5

    ERIC Educational Resources Information Center

    Bresser, Rusty; Melanese, Kathy; Sphar, Christine

    2009-01-01

    More than 10 percent of the students in our nation's public schools are English language learners, and this number grows each year. Many of these students are falling behind in math. "Supporting English Language Learners in Math Class, Grades 3-5" outlines the challenges ELL students face when learning math and provides a wealth of specific…

  7. A Fast Liquid Chromatography Tandem Mass Spectrometric Analysis of PETN (Pentaerythritol Tetranitrate), RDX (3,5-Trinitro-1,3,5-triazacyclohexane) and HMX (Octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine) in Soil, Utilizing a Simple Ultrasonic-Assisted Extraction with Minimum Solvent.

    PubMed

    Anilanmert, Beril; Aydin, Muhammet; Apak, Resat; Avci, Gülfidan Yenel; Cengiz, Salih

    2016-01-01

    Direct analyses of explosives in soil using liquid chromatography tandem mass spectrometry (LC-MS/MS) methods are very limited in the literature and require complex procedures or relatively high amount of solvent. A simple and rapid method was developed for the determination of pentaerythritol tetranitrate (PETN), 3,5-trinitro-1,3,5-triazacyclohexane (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), which are among the explosives used in terrorist attacks. A one-step extraction method for 1.00 g soil with 2.00 mL acetonitrile, and a 8-min LC-MS/MS method was developed. The detection limits for PETN, RDX and HMX were 5.2, 8.5 and 3.4 ng/g and quantitation limits were 10.0, 24.5, 6.0 ng/g. The intermediate precisions and Horwitz Ratio's were between 4.10 - 13.26% and 0.24 - 0.98, in order. This method was applied to a model post-blast debris collected from an artificial explosion and real samples collected after a terrorist attack in Istanbul. The method is easy and fast and requires less solvent use than other methods. PMID:27302580

  8. SUBCHRONIC TOXICITY OF 1,3,5-TRINITROBENZENE IN FISCHER 344 RATS

    EPA Science Inventory

    The subchronic toxicity of 1,3,5-trinitrobenzene (TNB) in male and female Fischer 344 rats was evaluated by feeding a powdered certified laboratory diet containing 0, 66.7, 400 and 800 mg TNB/kg diet for 90 days. The calculated average TNB intake was 4.29, 24.70, and 49.28 mg/kg...

  9. Earthwatch: Designing Environmental Education into the Curriculum. Volume I, Grades 3-5.

    ERIC Educational Resources Information Center

    Schaefer, Larry, Ed.; Hungerford, Nancy, Ed.

    This environmental education activities package for grades 3-5 contains activities in the following curriculum areas: (1) social science; (2) science; (3) language arts; and (4) mathematics. The activities are divided into seven sections based on seven environmental topics: (1) ecosystems; (2) population; (3) energy and resources; (4) economics,…

  10. Algebraic Reasoning: Professor Arbegla Introduces Variables and Functions. GEMS Teacher's Guide for Grades 3-5.

    ERIC Educational Resources Information Center

    Kopp, Jaine; Bergman, Lincoln

    This teacher guide helps build a solid foundation in algebra for students in grades 3-5 in which students gain essential understanding of properties of numbers, variables, functions, equations, and formulas. Throughout the problem solving activities, students use computational skills and gain a deeper understanding of the number system. Students…

  11. CHRONIC TOXICITY OF 1,3,5-TRINITROBENZENE IN FISCHER 344 RATS

    EPA Science Inventory

    The chronic toxicity of 1,3,5-trinitrobenzene (TNB) in male and female Fischer 344 (F344) rats was evaluated by feeding a diet containing 0, 5, 60 and 300 ppm of TNB for 2 years. The calculated average TNB intake over 2 years for males and females was 0.22, 2.64, 13.44 and 0.23,...

  12. Identification of distinct biological functions for four 3'-5' RNA polymerases.

    PubMed

    Long, Yicheng; Abad, Maria G; Olson, Erik D; Carrillo, Elisabeth Y; Jackman, Jane E

    2016-09-30

    The superfamily of 3'-5' polymerases synthesize RNA in the opposite direction to all other DNA/RNA polymerases, and its members include eukaryotic tRNA(His) guanylyltransferase (Thg1), as well as Thg1-like proteins (TLPs) of unknown function that are broadly distributed, with family members in all three domains of life. Dictyostelium discoideum encodes one Thg1 and three TLPs (DdiTLP2, DdiTLP3 and DdiTLP4). Here, we demonstrate that depletion of each of the genes results in a significant growth defect, and that each protein catalyzes a unique biological reaction, taking advantage of specialized biochemical properties. DdiTLP2 catalyzes a mitochondria-specific tRNA(His) maturation reaction, which is distinct from the tRNA(His) maturation reaction typically catalyzed by Thg1 enzymes on cytosolic tRNA. DdiTLP3 catalyzes tRNA repair during mitochondrial tRNA 5'-editing in vivo and in vitro, establishing template-dependent 3'-5' polymerase activity of TLPs as a bona fide biological activity for the first time since its unexpected discovery more than a decade ago. DdiTLP4 is cytosolic and, surprisingly, catalyzes robust 3'-5' polymerase activity on non-tRNA substrates, strongly implying further roles for TLP 3'-5' polymerases in eukaryotes.

  13. 3-Chlorotyrosine and 3,5-Dichlorotyrosine as biomarkers of respiratory tract exposure to chlorine gas

    EPA Science Inventory

    Modification of tyrosine by reactive chlorine can produce both 3-chlorotyrosine (CY) and 3,5-dichlorotyrosine (dCY). Both of these amino acids have proven to be promising biomarkers for assessing the extent of myeloperoxidase-catalyzed chlorine stress in a number of adverse physi...

  14. The Self-Assembly Properties of a Benzene-1,3,5-tricarboxamide Derivative

    ERIC Educational Resources Information Center

    Stals, Patrick J. M.; Haveman, Jan F.; Palmans, Anja R. A.; Schenning, Albertus P. H. J.

    2009-01-01

    A series of experiments involving the synthesis and characterization of a benzene-1,3,5-tricarboxamide derivative and its self-assembly properties are reported. These laboratory experiments combine organic synthesis, self-assembly, and physical characterization and are designed for upper-level undergraduate students to introduce the topic of…

  15. Investigation of Unexpected Reaction Intermediates in the Alkaline Hydrolysis of Methyl 3,5-Dinitrobenzoate

    ERIC Educational Resources Information Center

    Silva, Clesia C.; Silva, Ricardo O.; Navarro, Daniela M. A. F.; Navarro, Marcelo

    2009-01-01

    An experimental project aimed at identifying stable reaction intermediates is described. Initially, the studied reaction appears to involve the simple hydrolysis, by aqueous sodium hydroxide, of methyl 3,5-dinitrobenzoate dissolved in dimethyl sulfoxide. On mixing the substrates, however, the reaction mixture unexpectedly turns an intense red in…

  16. Preparation of 1,3,5-triamo-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-05-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  17. Preparation of 1,3,5-triamino-2,4,6-trinitrobenzene of submicron particle size

    DOEpatents

    Rigdon, Lester P.; Moody, Gordon L.; McGuire, Raymond R.

    2001-01-01

    A method is disclosed for the preparation of very small particle size, relatively pure 1,3,5-triamino-2,4,6-trinitrobenzene (TATB). Particles of TATB prepared according to the disclosed method are of submicron size and have a surface area in the range from about 3.8 to 27 square meters per gram.

  18. Teacher Implementation of Guided Reading and the Effect on Students in Grades 3-5

    ERIC Educational Resources Information Center

    Huber, Melissa S.

    2011-01-01

    This mixed methods study explored implementing guided reading in grades 3-5 in a suburban school district located in Southeastern Pennsylvania. The purpose of this study was to evaluate how teachers implement guided reading in their classrooms and how the use of guided reading affects student achievement in Text Structure and Vocabulary, Reading…

  19. 3':5'-cyclic AMP and hormonal control of puparium formation in the fleshfly Sarcophaga bullata.

    PubMed

    Fraenkel, G; Blechl, A; Blechl, J; Herman, P; Seligman, M I

    1977-05-01

    Injection of 3':5'-cyclic AMP (cAMP) into larvae of the fly Sarcophaga bullata 3-4 hr before the beginning of puparium formation (red-spiracle stage) greatly accelerates the onset of tanning without affecting initiation of puparium formation (anterior retraction). Accelerated tanning resembles real tanning in two important respects: the solubility of cuticular proteins becomes reduced and [U-14C]tyrosine is incorporated into the cuticle. Of a number of cAMP analogues tested, 3':5'- cyclic GMP, 2':3'-cyclic AMP, and 5'-AMP were inactive, dibutyryl-3':5'-cAMP had only slight activity, and cyclic IMP and deoxy-3':5'-cAMP showed some activity. Theophylline enhanced the effect of small doses of cAMP or of blood, diluted 1:8, active in the puparium tanning factor. Injection of dopa, dopamine, acetyldopamine, or epinephrine, but not of tyrosine, had an accelerating effect similar to that of cAMP. The tanning-inhibiting effect of DL-alpha-methyl-alpha-hydrazino-beta-(3,4-dihydroxyphenyl)propionic acid monohydrate is reversed by dopamine or epinephrine, but not by tyrosine, dopa, or cAMP. Evidence is presented to indicate that the responses to cAMP are not artifacts but reflect actual biochemical events during tanning.

  20. Russian/English Interdisciplinary Lessons for General Education and Special Education Students. Grades 3-5.

    ERIC Educational Resources Information Center

    New York City Board of Education, Brooklyn, NY. Office of Bilingual Education.

    The materials consist of four lessons each at grade levels 3-5, designed for use by both Russian bilingual and English-monolingual teachers in general and special education. The lessons are cross-referenced to learning and performance standards established for New York City (New York) public schools. Each unit (group of grade-level lessons)…

  1. FIRBACK Cosmological Survey With ISO: Observing the Cosmic Infrared Background at 170 microns

    NASA Astrophysics Data System (ADS)

    Dole, H.; Gispert, R.; Lagache, G.; Puget, J.-L.; Aussel, H.; Bouchet, F. R.; Ciliegi, P.; Clements, D. L.; Cesarsky, C. J.; Désert, F.-X.; Elbaz, D.; Franceschini, A.; Guiderdoni, B.; Harwit, M.; Laureijs, R.; Lemke, D.; McMahon, R.; Moorwood, A. F. M.; Oliver, S.; Reach, W. T.; Rowan-Robinson, M.; Stickel, M.

    FIRBACK, one of the deepest surveys performed at 170 microns with ISOPHOT, is aimed at the study of the Cosmic Far Infrared Background (CIB). We just summarize here the main results: 1. we studied the footprint of PHOT at 170 microns and check the calibration (see Lagache, 99a) 2. source counts of resolved galaxies suggest strong evolution (see Dole, 99) 3. fluctuations of the CIB are detected (see Lagache, 99)

  2. Nonthermal 10 micron CO2 emission lines in the atmospheres of Mars and Venus

    NASA Technical Reports Server (NTRS)

    Johnson, M. A.; Betz, A. L.; Mclaren, R. A.; Townes, C. H.; Sutton, E. C.

    1976-01-01

    Mechanisms are examined for excitation of strong 10-micron CO2 emission lines seen on Mars and Venus. Line absorption of near-infrared solar flux directly by CO2 or H2O with collisional transfer of energy to CO2 are proposed as likely excitation mechanisms. Altitudes for peak 10-micron emission are estimated to be near 80 km for Mars and 120 km for Venus.

  3. Preparation and Characterization of Micronized Artemisinin via a Rapid Expansion of Supercritical Solutions (RESS) Method

    PubMed Central

    Yu, Huimin; Zhao, Xiuhua; Zu, Yuangang; Zhang, Xinjuan; Zu, Baishi; Zhang, Xiaonan

    2012-01-01

    The particle sizes of pharmaceutical substances are important for their bioavailability. Bioavailability can be improved by reducing the particle size of the drug. In this study, artemisinin was micronized by the rapid expansion of supercritical solutions (RESS). The particle size of the unprocessed white needle-like artemisinin particles was 30 to 1200 μm. The optimum micronization conditions are determined as follows: extraction temperature of 62 °C, extraction pressure of 25 MPa, precipitation temperature 45 °C and nozzle diameter of 1000 μm. Under the optimum conditions, micronized artemisinin with a (mean particle size) MPS of 550 nm is obtained. By analysis of variance (ANOVA), extraction temperature and pressure have significant effects on the MPS of the micronized artemisinin. The particle size of micronized artemisinin decreased with increasing extraction temperature and pressure. Moreover, the SEM, LC-MS, FTIR, DSC and XRD allowed the comparison between the crystalline initial state and the micronization particles obtained after the RESS process. The results showed that RESS process has not induced degradation of artemisinin and that processed artemisinin particles have lower crystallinity and melting point. The bulk density of artemisinin was determined before and after RESS process and the obtained results showed that it passes from an initial density of 0.554 to 0.128 g·cm−3 after the processing. The decrease in bulk density of the micronized powder can increase the liquidity of drug particles when they are applied for medicinal preparations. These results suggest micronized powder of artemisinin can be of great potential in drug delivery systems. PMID:22606030

  4. Fluorescent and nonfluorescent crystals of N-(3,5-dihalogenosalicylidene)-2-methoxyaniline

    NASA Astrophysics Data System (ADS)

    Tsuchimoto, Masanobu; Yoshida, Narihiro; Sugimoto, Atsuki; Teramoto, Naozumi; Nakajima, Kiyohiko

    2016-02-01

    Crystals of N-(3,5-diXsalicylidene)-2-methoxyaniline (X = fluoro, chloro, bromo, and iodo) were prepared, and their structural and luminescence properties in the solid state were investigated. Only fluorescent orange crystals were obtained for N-(3,5-difluorosalicylidene)-2-methoxyaniline (1). Both fluorescent orange crystals (2a) and nonfluorescent red-orange crystals (2b) were obtained for N-(3,5-dichlorosalicylidene)-2-methoxyaniline. Slightly fluorescent orange crystals were obtained for N-(3,5-dibromosalicylidene)-2-methoxyaniline (3) and N-(3,5-diiodosalicylidene)-2-methoxyaniline (4). Fluorescence spectra of 1, 2a, 3, and 4 in the solid state show a fluorescence band at around 600 nm by excitation at 480 nm. The fluorescence intensities were in the order 1 > 2a > 3 > 4. X-ray crystal-structure analyses of 1, 2a, and 2b were obtained. The N-salicylideneaniline molecules in all of the crystals have planar structures. The molecules in both 1 and 2b take the enol form, while the molecules in 2a take the cis-keto form. The crystals 2a include water of crystallization, which is hydrogen bonded to the adjacent N-salicylideneaniline molecules. Molecules in fluorescent 2a are arranged in stacks along the a-axis to form a columnar structure in the crystals. In contrast, molecules in nonfluorescent 2b are strongly π-π stacked to form dimers in crystals. The orange crystals 2a were transformed to the red-orange crystals 2b by removal of water of crystallization upon heating at 70 °C.

  5. Surgical Management of Tibial Plateau Fractures With 3.5 mm Simple Plates

    PubMed Central

    Bagherifard, Abolfazl; Jabalameli, Mahmoud; Hadi, Hosseinali; Rahbar, Mohammad; Minator Sajjadi, Mohammadreza; Jahansouz, Ali; Karimi Heris, Hossein

    2016-01-01

    Background Tibial plateau fractures can be successfully fixed utilizing 3.5 mm locking plates. However, there are some disadvantages to using these plates. Objectives In the current prospective study, we investigated the outcome of treating different types of tibial plateau fractures with 3.5 mm simple plates which, to our knowledge, has not been evaluated in previous studies. Materials and Methods Between 2011 and 2013, 32 patients aged 40 ± 0.2 years underwent open reduction and internal fixation for tibial plateau fractures with 3.5 mm simple plates. The patients were followed for 16.14 ± 2.1 months. At each patient’s final visit, the articular surface depression, medial proximal tibial angle, and slope angle were measured and compared with measurements taken early after the operation. The functional outcomes were measured with the WOMAC and Lysholm knee scores. Results The mean union time was 13 ± 1.2 weeks. The mean knee range of motion was 116.8° ± 3.3°. The mean WOMAC and Lysholm scores were 83.5 ± 1.8 and 76.8 ± 1.6, respectively. On the early postoperative and final X-rays, 87.5% and 84% of patients, respectively, had acceptable reduction. Medial proximal tibial and slope angles did not change significantly by the last visit. No patient was found to have complications related to the type of plate. Conclusions In this case series study, the fixation of different types of tibial plateau fractures with 3.5 mm simple non-locking and non-precontoured plates was associated with acceptable clinical, functional, and radiographic outcomes. Based on the advantages and costs of these plates, the authors recommend using 3.5 mm simple plates for different types of tibial plateau fractures. PMID:27626010

  6. 3,5-Dihydroxybenzoic acid, a specific agonist for hydroxycarboxylic acid 1, inhibits lipolysis in adipocytes.

    PubMed

    Liu, Changlu; Kuei, Chester; Zhu, Jessica; Yu, Jingxue; Zhang, Li; Shih, Amy; Mirzadegan, Taraneh; Shelton, Jonathan; Sutton, Steven; Connelly, Margery A; Lee, Grace; Carruthers, Nicholas; Wu, Jiejun; Lovenberg, Timothy W

    2012-06-01

    Niacin raises high-density lipoprotein and lowers low-density lipoprotein through the activation of the β-hydroxybutyrate receptor hydroxycarboxylic acid 2 (HCA2) (aka GPR109a) but with an unwanted side effect of cutaneous flushing caused by vascular dilation because of the stimulation of HCA2 receptors in Langerhans cells in skin. HCA1 (aka GPR81), predominantly expressed in adipocytes, was recently identified as a receptor for lactate. Activation of HCA1 in adipocytes by lactate results in the inhibition of lipolysis, suggesting that agonists for HCA1 may be useful for the treatment of dyslipidemia. Lactate is a metabolite of glucose, suggesting that HCA1 may also be involved in the regulation of glucose metabolism. The low potency of lactate to activate HCA1, coupled with its fast turnover rate in vivo, render it an inadequate tool for studying the biological role of lactate/HCA1 in vivo. In this article, we demonstrate the identification of 3-hydroxybenzoic acid (3-HBA) as an agonist for both HCA2 and HCA1, whereas 3,5-dihydroxybenzoic acid (3,5-DHBA) is a specific agonist for only HCA1 (EC(50) ∼150 μM). 3,5-DHBA inhibits lipolysis in wild-type mouse adipocytes but not in HCA1-deficient adipocytes. Therefore, 3,5-DHBA is a useful tool for the in vivo study of HCA1 function and offers a base for further HCA1 agonist design. Because 3-HBA and 3,5-DHBA are polyphenolic acids found in many natural products, such as fruits, berries, and coffee, it is intriguing to speculate that other heretofore undiscovered natural substances may have therapeutic benefits.

  7. Toxicity of the explosives 2,4,6-trinitrotoluene, hexahydro-1,3,5-trinitro-1,3,5-triazine, and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine in sediments to Chironomus tentans and Hyalella azteca: low-dose hormesis and high-dose mortality.

    PubMed

    Steevens, Jeffery A; Duke, B Maurice; Lotufo, Guilherme R; Bridges, Todd S

    2002-07-01

    The toxicity of the explosives 2,4,6-trinitrotoluene (TNT); hexahydro-1,3,5-trinitro-1,3,5-triazine (royal demolition explosive [RDX]); and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (high-melting explosive [HMX]), was evaluated in spiked sediment with two freshwater invertebrates. The midge Chironomus tentans and the amphipod Hyalella azteca demonstrated significant toxic effects after exposure to TNT and its degradation products, 1,3,5-trinitrobenzene (TNB) and 2,4-diamino-6-nitrotoluene (2,4-DANT). Significant reductions in survival of C. tentans exposed to TNT, TNB, and 2,4-DANT were observed at nominal sediment concentrations as low as 200 mg/kg. Hyalella azteca was more sensitive to TNT, TNB, and 2,4-DANT than the midge, where significant reductions in survival were observed at nominal concentrations of 50, 100, and 200 mg/kg, respectively. Survival of the midge and the amphipod was unaffected after exposure to RDX or HMX at the highest concentrations of 1,000 and 400 mg/kg, respectively. Growth of the midge, measured as total weight, was significantly reduced by 2,4-DANT. However, significantly increased growth was observed after exposure to sublethal concentrations of RDX and HMX. Although significant reductions in amphipod survival were observed at high concentrations of TNB, growth was significantly increased at sublethal concentrations. The results of the current investigation suggest that organisms exposed to explosives at contaminated sites may be affected at concentrations less than 25 mg/kg through hormetic growth enhancement and at higher concentrations through increased mortality.

  8. Nitro Derivatives of 1,3,5-Triazepine as Potential High-Energy Materials

    NASA Astrophysics Data System (ADS)

    Singh, Hari Ji; Upadhyay, Manish Kumar

    2013-10-01

    Structure optimization and frequency calculation of six nitro derivatives of 1,3,5-triazepine were performed using a MP2(FULL)/6-311G(d,p) method. In order to obtain reliable energy data, single-point energy and subsequently thermodynamic properties of the species considered were calculated at a fairly high level of theory, CCSD(T)/6-311G(d,p). Solid-phase heats of formation and crystal density were determined using an electrostatic potential (ESP) method utilizing wave function analysis-surface analysis suite (WFA-SAS) code. The result shows that all nitro derivatives possess high positive heats of formation that increase with an increase in the number of nitro groups attached to the ring moiety. The crystal density was found to be in the range of 1.67-1.90 g/cm3. Detonation properties of the compounds were estimated using the Kamlet-Jacobs equation. The results showed that detonation velocity (D) and detonation pressure (P) increased with an increase in the number of nitro groups attached at the ring moiety. It was found that all six nitro derivatives of the title compound had better or comparable performance characteristics than the most widely used commercial explosives, such as TNT, research and development explosives (RDX), and 1,3,5,7-tetranitro-1,3,5,7-tetrazocane (HMX). The trinitro derivative (1,3,5-trinitro-1,3,5-triazepine, F) yielded detonation pressure (P) and detonation velocity (D) of 45.5 GPa and 9.23 km/s, respectively, at a loading density of 1.90 g/cm3, which are superior to the most powerful available explosive HMX (P = 39.00 GPa and D = 9.11 km/s). The results obtained during the present study show that the title compounds can be used as promising futuristic high-energy-density materials (HEDMs).

  9. The Carnegie Hubble Program: The Leavitt Law at 3.6 microns and 4.5 microns in the Large Magellanic Cloud

    NASA Technical Reports Server (NTRS)

    Scowcroft, Victoria; Freedman, Wendy L.; Madore, Barry F.; Monson, Andrew J.; Persson, S. E.; Seibert, Mark; Rigby, Jane R.; Sturch, Laura

    2011-01-01

    The Carnegie Hubble Program (CHP) is designed to improve the extragalactic distance scale using data from the post-cryogenic era of Spitzer. The ultimate goal is a determination of the Hubble constant to an accuracy of 2%. This paper is the first in a series on the Cepheid population of the Large Magellanic Cloud, and focuses on the period-luminosity relations (Leavitt laws) that will be used, in conjunction with observations of Milky Way Cepheids, to set the slope and zero-point of the Cepheid distance scale in the mid-infrared. To this end, we have obtained uniformly-sampled light curves for 85 LMC Cepheids, having periods between 6 and 140 days. Period- luminosity and period-color relations are presented in the 3.6 micron and 4.5 micron bands. We demonstrate that the 3.6 micron band is a superb distance indicator. The cyclical variation of the [3.6]-[4.5] color has been measured for the first time. We attribute the amplitude and phase of the color curves to the dissociation and recombination of CO molecules in the Cepheid s atmosphere. The CO affects only the 4.5 micron flux making it a potential metallicity indicator.

  10. Advanced 2-micron Solid-state Laser for Wind and CO2 Lidar Applications

    NASA Technical Reports Server (NTRS)

    Yu, Jirong; Trieu, Bo C.; Petros, Mulugeta; Bai, Yingxin; Petzar, Paul J.; Koch, Grady J.; Singh, Upendra N.; Kavaya, Michael J.

    2006-01-01

    Significant advancements in the 2-micron laser development have been made recently. Solid-state 2-micron laser is a key subsystem for a coherent Doppler lidar that measures the horizontal and vertical wind velocities with high precision and resolution. The same laser, after a few modifications, can also be used in a Differential Absorption Lidar (DIAL) system for measuring atmospheric CO2 concentration profiles. The world record 2-micron laser energy is demonstrated with an oscillator and two amplifiers system. It generates more than one joule per pulse energy with excellent beam quality. Based on the successful demonstration of a fully conductive cooled oscillator by using heat pipe technology, an improved fully conductively cooled 2-micron amplifier was designed, manufactured and integrated. It virtually eliminates the running coolant to increase the overall system efficiency and reliability. In addition to technology development and demonstration, a compact and engineering hardened 2-micron laser is under development. It is capable of producing 250 mJ at 10 Hz by an oscillator and one amplifier. This compact laser is expected to be integrated to a lidar system and take field measurements. The recent achievements push forward the readiness of such a laser system for space lidar applications. This paper will review the developments of the state-of-the-art solid-state 2-micron laser.

  11. A new spectral feature on the trailing hemisphere of Europa at 3.78 microns

    NASA Astrophysics Data System (ADS)

    Trumbo, Samantha K.; Fischer, Patrick D.; Brown, Michael E.

    2016-10-01

    We present hemispherically resolved spectra of the surface of Europa from 3.4 – 4.15 microns, which we obtained using Keck NIRSPEC. These include the first high-quality L-band spectra of the surface to extend beyond 4 microns. In our data, we identify a previously unseen spectral feature at 3.78 microns on the trailing hemisphere. This feature is coincident with an SO2 frost absorption. However the corresponding, typically stronger 4.07-micron feature of SO2 frost is absent from our data. This result is contrary to the suggested detection of SO2 at 4.05 microns in Galileo NIMS data [1] of the trailing hemisphere, which was severely affected by radiation noise. Thus, we use simple spectral modeling to argue that the 3.78-micron feature is not easily explained by the presence of SO2 frost on the surface. However, the longitudinal distribution of the feature is consistent with that of a radiolytic product. We explore alternative explanations and discuss other potential candidate species. [1] Hansen and McCord (2008) GRL, 35: L01202.

  12. New long-wavelength Nd:YAG laser at 1. 44 micron: effect on brain

    SciTech Connect

    Martiniuk, R.; Bauer, J.A.; McKean, J.D.; Tulip, J.; Mielke, B.W.

    1989-02-01

    A wavelength-shifted Nd:YAG laser, tuned to coincide with the infrared absorption peak of water at 1.44 microns, was used to make lesions in normal rabbit brain. A total of 48 lesions were made with power up to 20 W, with energy up to 40 joules, and with two different spot sizes. These lesions were compared to lesions made with 1.06 microns radiation from an Nd:YAG laser under identical operating conditions. Measurements of blood-brain barrier damage and width, depth, and volume of tissue affected were obtained 30 minutes after placement of the lesions. It was found that 1.44-microns lesions produced photoevaporative tissue loss at the highest intensities used. The layer of coagulated tissue remaining after photovaporization had a mean thickness of 0.6 mm irrespective of the volume of tissue removed. There was no photovaporization in the 1.06-microns lesions. In addition, the amount of peripheral edema per unit volume of tissue coagulated was approximately half at the 1.44-microns wavelength. These findings suggest that the 1.44-microns Nd:YAG laser may be a useful surgical instrument since it combines the photoevaporative effect of the CO/sub 2/ laser while maintaining the advantages of the conventional Nd:YAG laser (quartz fiber delivery and effective hemostasis).

  13. Preliminary evaluation of a pulsed 2.15-micron laser system for fiberoptic endoscopic surgery.

    PubMed

    Treat, M R; Trokel, S L; Reynolds, R D; DeFilippi, V J; Andrew, J; Liu, J Y; Cohen, M G

    1988-01-01

    There is a need for lasers that are compatible with fiberoptic endoscopes and that provide greater cutting precision than currently can be produced by the widely used Nd:YAG (1.06 micron) laser. Recently available lasers that operate in the 2-micron region fill this need. This laser light energy can be transmitted by low OH- silica fibers and has much less tissue penetration than radiation at 1.06 micron. We have been evaluating a prototype solid state laser system that produces pulses of 2.15 microns light that is delivered by a silica based fiberoptic delivery system with negligible transmission losses. This system is based on a thulium-holmium-chromium doped YAG (Tm-Ho-Cr: YAG) rod that lases at 2.15 micron. The laser does not require cryogenic cooling, toxic gases, or custom utilities and should be practical in a clinical environment. In vivo animal testing of this laser confirms that it provides greater ablating precision than does the Nd:YAG laser at 1.06 micron.

  14. Computational prediction of probabilistic ignition threshold of pressed granular octahydro-1,3,5,7-tetranitro-1,2,3,5-tetrazocine (HMX) under shock loading

    NASA Astrophysics Data System (ADS)

    Kim, Seokpum; Miller, Christopher; Horie, Yasuyuki; Molek, Christopher; Welle, Eric; Zhou, Min

    2016-09-01

    The probabilistic ignition thresholds of pressed granular octahydro-1,3,5,7-tetranitro-1,2,3,5-tetrazocine explosives with average grain sizes between 70 μm and 220 μm are computationally predicted. The prediction uses material microstructure and basic constituent properties and does not involve curve fitting with respect to or prior knowledge of the attributes being predicted. The specific thresholds predicted are James-type relations between the energy flux and energy fluence for given probabilities of ignition. Statistically similar microstructure sample sets are computationally generated and used based on the features of micrographs of materials used in actual experiments. The predicted thresholds are in general agreement with measurements from shock experiments in terms of trends. In particular, it is found that grain size significantly affects the ignition sensitivity of the materials, with smaller sizes leading to lower energy thresholds required for ignition. For example, 50% ignition threshold of the material with an average grain size of 220 μm is approximately 1.4-1.6 times that of the material with an average grain size of 70 μm in terms of energy fluence. The simulations account for the controlled loading of thin-flyer shock experiments with flyer velocities between 1.5 and 4.0 km/s, constituent elasto-viscoplasticity, fracture, post-fracture contact and friction along interfaces, bulk inelastic heating, interfacial frictional heating, and heat conduction. The constitutive behavior of the materials is described using a finite deformation elasto-viscoplastic formulation and the Birch-Murnaghan equation of state. The ignition thresholds are determined via an explicit analysis of the size and temperature states of hotspots in the materials and a hotspot-based ignition criterion. The overall ignition threshold analysis and the microstructure-level hotspot analysis also lead to the definition of a macroscopic ignition parameter (J) and a microscopic

  15. Zonal Wave Number 2 Rossby Wave (3.5-day oscillation) Over The Martian Lower Atmosphere

    NASA Astrophysics Data System (ADS)

    Ghosh, P.; Thokuluwa, R. K.

    2013-12-01

    Over the Mars, height (800-50 Pascal pressure coordinate) profiles of temperature (K), measured by radio occultation technique during the MGS (Mars Global Surveyor) mission, obtained for the period of 1-10 January 2006 at the Martian latitude of ~63N in almost all the longitudes are analyzed to study the characteristics of the 3.5-day oscillation. To avoid significant data gaps in a particular longitude sector, we selected a set of 7 Mars longitude regions with ranges of 0-30E, 35-60E, 65-95E, 190-230E, 250-280E, 290-320E, and 325-360E to study the global characteristics of the 3.5-day oscillation. The 3.5-day oscillation is not selected as a-priori but observed as a most significant oscillation during this period of 1-10 January 2006. It is observed that in the longitude of 0-30E, the 3.5-day oscillation shows statistically significant power (above the 95% confidence level white noise) from the lowest height (800 Pascal, 8 hPa) itself and up to the height of 450 Pascal level with the maximum power of ~130 K^2 at the 600 & 650 Pascal levels. It started to grow from the power of ~ 50 K^2 at the lowest height of 800 Pascal level and reached the maximum power in the height of 600-650 Pascal level and then it started to get lessened monotonously up to the height of 450 Pascal level where its power is ~ 20 K^2. Beyond this height and up to the height of 50 Pascal level, the wave amplitude is below the white noise level. As the phase of the wave is almost constant at all the height levels, it seems that the observed 3.5-day oscillation is a stationary wave with respect to the height. In the 35-60 E longitude sector, the vertical structure of the 3.5-day oscillation is similar to what observed for the 0-30 E longitude region but the power is statistically insignificant at all the heights. However in the 65-95E longitude sector, the wave grows from the lowest level (70 K^2) of 800 Pascal to its maximum power of 280 K^2 in the height of 700 Pascal level and then it started

  16. Fission Spectrum Related Uncertainties

    SciTech Connect

    G. Aliberti; I. Kodeli; G. Palmiotti; M. Salvatores

    2007-10-01

    The paper presents a preliminary uncertainty analysis related to potential uncertainties on the fission spectrum data. Consistent results are shown for a reference fast reactor design configuration and for experimental thermal configurations. However the results obtained indicate the need for further analysis, in particular in terms of fission spectrum uncertainty data assessment.

  17. Radiation detector spectrum simulator

    DOEpatents

    Wolf, Michael A.; Crowell, John M.

    1987-01-01

    A small battery operated nuclear spectrum simulator having a noise source nerates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith generates several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  18. Radiation detector spectrum simulator

    DOEpatents

    Wolf, M.A.; Crowell, J.M.

    1985-04-09

    A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  19. Fetal Alcohol Spectrum Disorder

    ERIC Educational Resources Information Center

    Caley, Linda M.; Kramer, Charlotte; Robinson, Luther K.

    2005-01-01

    Fetal alcohol spectrum disorder (FASD) is a serious and widespread problem in this country. Positioned within the community with links to children, families, and healthcare systems, school nurses are a critical element in the prevention and treatment of those affected by fetal alcohol spectrum disorder. Although most school nurses are familiar…

  20. The CMBR spectrum

    SciTech Connect

    Stebbins, A.

    1997-05-01

    Here we give an introduction to the observed spectrum of the Cosmic Microwave Background Radiation (CMBR) and discuss what can be learned about it. Particular attention will be given to how Compton scattering can distort the spectrum of the CMBR. An incomplete bibliography of relevant papers is also provided.

  1. 0.351 micron Laser Beam propagation in High-temperature Plasmas

    SciTech Connect

    Froula, D; Divol, L; Meezan, N; Ross, J; Berger, R L; Michel, P; Dixit, S; Rekow, V; Sorce, C; Moody, J D; Neumayer, P; Pollock, B; Wallace, R; Suter, L; Glenzer, S H

    2007-12-10

    A study of the laser-plasma interaction processes have been performed in plasmas that are created to emulate the plasma conditions in indirect drive inertial confinement fusion targets. The plasma emulator is produced in a gas-filled hohlraum; a blue 351-nm laser beam propagates along the axis of the hohlraum interacting with a high-temperature (T{sub e} = 3.5 keV), dense (n{sub e} = 5 x 10{sup 20}cm{sup -3}), long-scale length (L {approx} 2 mm) plasma. Experiments at these conditions have demonstrated that the interaction beam produces less than 1% total backscatter resulting in transmission greater than 90% for laser intensities less than I < 2 x 10{sup 15} W-cm{sup -2}. The bulk plasma conditions have been independently characterized using Thomson scattering where the peak electron temperatures are shown to scale with the hohlraum heater beam energy in the range from 2 keV to 3.5 keV. This feature has allowed us to determine the thresholds for both backscattering and filamentation instabilities; the former measured with absolutely calibrated full aperture backscatter and near backscatter diagnostics and the latter with a transmitted beam diagnostics. A plasma length scaling is also investigated extending our measurements to 4-mm long high-temperature plasmas. At intensities I < 5 x 10{sup 14} W-cm{sup -2}, greater than 80% of the energy in the laser is transmitted through a 5-mm long, high-temperature (T{sub e} > 2.5 keV) high-density (n{sub e} = 5 x 10{sup 20} w-cm{sup -3}) plasma. Comparing the experimental results with detailed gain calculations for the onset of significant laser scattering processes shows a stimulated Brillouin scattering threshold (R=10%) for a linear gain of 15; these high temperature, low density experiments produce plasma conditions comparable to those along the outer beams in ignition hohlraum designs. By increasing the gas fill density (n{sub e} = 10{sup 21} cm{sup -3}) in these targets, the inner beam ignition hohlraum conditions are

  2. Control of Stationary Cross-Flow Modes in a Mach 3.5 Boundary Layer Using Patterned Passive and Active Roughness

    NASA Technical Reports Server (NTRS)

    Schuele, Chan Yong

    2011-01-01

    Spanwise-periodic roughness designed to excite selected wavelengths of stationary cross- ow modes was investigated in a 3-D boundary layer at Mach 3.5. The test model was a sharp-tipped 14deg right-circular cone. The model and integrated sensor traversing system were placed in the Mach 3.5 Supersonic Low Disturbance Tunnel (SLDT) equipped with a "quiet design" nozzle at the NASA Langley Research Center. The model was oriented at a 4:2deg angle of attack to produce a mean cross-fl ow velocity component in the boundary layer over the cone. Five removable cone tips have been investigated. One has a smooth surface that is used to document the baseline ("natural") conditions. Two had minute (20 - 40 micron) "dimples" that are equally spaced around the circumference, at a streamwise location that is just upstream of the linear stability neutral growth branch for cross- ow modes. The azimuthal mode numbers of the dimpled tips were selected to either enhance the most amplified wave numbers, or to suppress the growth of the most amplified wave numbers. Two of the cone tips had an array of plasma streamwise vortex generators that were designed to simulate the disturbances produced by the passive patterned roughness. The results indicate that the stationary cross-fl ow modes were highly receptive to the patterned roughness of both passive and active types. The patterned passive roughness that was designed to suppress the growth of the most amplified modes had an azimuthal wavelength that was 66% smaller that that of the most amplified stationary cross- ow mode. This had the effect to increase the transition Reynolds number from 25% to 50% depending on the measurement technique. The application of the research is on turbulent transition control on swept wings of supersonic aircraft. The plasma-based roughness has the advantage over the passive roughness of being able to be adaptable to different conditions that would occur during a flight mission.

  3. Fragrance material review on 3,5,5-trimethyl-1-hexanol.

    PubMed

    McGinty, D; Scognamiglio, J; Letizia, C S; Api, A M

    2010-07-01

    A toxicologic and dermatologic review of 3,5,5-trimethyl-1-hexanol when used as a fragrance ingredient is presented. 3,5,5-Trimethyl-1-hexanol is a member of the fragrance structural group branched chain saturated alcohols. The common characteristic structural elements of the alcohols with saturated branched chain are one hydroxyl group per molecule, and a C(4) to C(12) carbon chain with one or several methyl side chains. This review contains a detailed summary of all available toxicology and dermatology papers that are related to this individual fragrance ingredient and is not intended as a stand-alone document. A safety assessment of the entire branched chain saturated alcohol group will be published simultaneously with this document; please refer to Belsito et al. (2010) for an overall assessment of the safe use of this material and all other branched chain saturated alcohols in fragrances.

  4. 3.5-GHz intra-burst repetition rate ultrafast Yb-doped fiber laser

    NASA Astrophysics Data System (ADS)

    Kerse, Can; Kalaycıoğlu, Hamit; Elahi, Parviz; Akçaalan, Önder; Ilday, F. Ömer

    2016-05-01

    We report on an all-fiber Yb laser amplifier system with an intra-burst repetition rate of 3.5 GHz. The system is able to produce minimum of 15-ns long bursts containing approximately 50 pulses with a total energy of 215 μJ at a burst repetition rate of 1 kHz. The individual pulses are compressed down to the subpicosecond level. The seed signal from a 108 MHz fiber oscillator is converted to approximately 3.5 GHz by a multiplier consisting of six cascaded 50/50 couplers, and then amplified in ten stages. The highly cascaded amplification suppresses amplified spontaneous emission at low repetition rates. Nonlinear interactions between overlapping pulses within a burst is also discussed.

  5. Design and synthesis of 3,5-diarylpiperidin-2,6-diones as anticonvulsant agents.

    PubMed

    Babu, Mariappan; Pitchumani, Kasi; Ramesh, Penugonda

    2012-01-15

    The present Letter describes a one-pot multi-component method that allows the efficient and mild preparation of 3,5-diphenylpiperidin-2,6-dione and a new series of 3,5-diarylpiperidin-2,6-dione derivatives from ethyl 2-arylacetates, formaldehyde and ammonia/aliphatic/aromatic amines. The structures of the compounds were elucidated by IR, NMR spectroscopic data and microanalyses. The anticonvulsant activities of these compounds were evaluated by maximal electroshock seizure test and were also evaluated for motor impairment. Among the synthesized compounds, 5a, 5b, 5d, and 5e could be considered potentially the most useful and safe therapeutic compound and 5g, 5i, 5j, 5m, and 5o exhibit potent activities. PMID:22189139

  6. The 3.5-m all-SiC telescope for HERSCHEL

    NASA Astrophysics Data System (ADS)

    Toulemont, Yves; Passvogel, Thomas; Pilbratt, Goran L.; de Chambure, Daniel; Pierot, Dominique; Castel, Didier

    2004-10-01

    Placed on the L2 Lagrangian point, Herschel operates in the spectral range between 80 and 670 μm wavelength and is devoted to astronomical investigations in the far-infrared, sub-millimetre and millimetre wavelengths. The Herschel Telescope is an "all Silicon Carbide" Telescope, based on a 3.5-m-diameter Cassegrain design. The driving requirements are the large diameter (3;5m) which represents a manufacturing challenge, the WFE to be kept below 6μrms despite the operational temperature of 70K, and finally the mass to be kept below 300kg. The size of the Telescope has put some challenges in the manufacturing processes and the tests facilities installations. At this stage, the major critical phases which are the brazing and the grinding of the primary mirror have successfully been passed. The development and manufacturing of the Herschel Telescope is part of the Herschel Planck program funded by the European Space Agency (ESA).

  7. The 3.5m all SiC telescope for Herschel

    NASA Astrophysics Data System (ADS)

    Toulemont, Y.; Passvogel, T.; Pillbrat, G.; de Chambure, D.; Pierot, D.; Castel, D.

    2004-06-01

    Placed on the L2 Lagrangian point, Herschel operates in the spectral range between 80 and 670 μm wavelength and is devoted to astronomical investigations in the far-infrared, sub-millimetre and millimetre wavelengths. The Herschel Telescope is an "all Silicon Carbide" Telescope, based on a 3.5-m-diameter Cassegrain design. The driving requirements are the large diameter (3.5 m), the WFE to be kept below 6μrms despite the operational temperature (70K), and finally the mass to be kept below 300kg. The size of the Telescope has put some challenges in the manufacturing and the tests facilities installations. At this stage, the major critical phase which is the brazing of the primary mirror has successfully been passed. The development and manufacturing of the Herschel Telescope is part of the Herschel Planck program funded by the European Space Agency (ESA).

  8. Chiral 2 + 3 Keto-Enamine Pseudocyclophanes Derived from 1,3,5-Triformylphloroglucinol.

    PubMed

    Kieryk, Przemysław; Janczak, Jan; Panek, Jarosław; Miklitz, Marcin; Lisowski, Jerzy

    2016-01-01

    The reactions of 1,3,5-triformylphloroglucinol with (1R,2R)-1,2-diaminocyclohexane, (1R,2R)-1,2-diphenylethylenediamine, or (R)-2,2'-diamino-1,1'-binaphthyl result in the formation of enantiopure [2 + 3] keto-enamine condensation products, in contrast to analogous reactions of 1,3,5-triformylbenzene, where [4 + 6] Schiff base cages are formed. The X-ray crystal structure of the diaminocyclohexane 2 + 3 derivative as well as modeled structures of other compounds of this type show cyclophane-like molecules with close contact between the phloroglucinol rings. Density Functional Theory (DFT) calculations confirm that there is a sizable π-π interaction between these rings influencing the conformation of these molecules. PMID:26653342

  9. Poly[(μ-2-hy-droxy-3,5-dinitro-benzoato)rubidium].

    PubMed

    Meng, Yan

    2011-04-01

    The asymmetric unit of the title compound, [Rb(C(7)H(3)N(2)O(7))](n), comprises an Rb(+) cation and a 3,5-dinitro-salicylate ligand. The Rb(+) cation is 10-coordinated by O atoms from eight 3,5-dinitro-salicylate anions and is linked by three μ(2)-O atoms, forming a zigzag chain along the b-axis direction, which is further linked by the phenyl groups, giving the three-dimensional framework. The crystal structure involves intra-anionic O-H⋯O hydrogen bonds and strong π-π stacking inter-actions [centroid-centroid distance = 3.6755 (7) Å]. PMID:21753973

  10. 36 CFR 3.5 - Do I have to report an accident involving a vessel to the National Park Service?

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... accident involving a vessel to the National Park Service? 3.5 Section 3.5 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.5 Do I have to report an accident involving a vessel to the National Park Service? (a) The operator of a...

  11. 36 CFR 3.5 - Do I have to report an accident involving a vessel to the National Park Service?

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... accident involving a vessel to the National Park Service? 3.5 Section 3.5 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.5 Do I have to report an accident involving a vessel to the National Park Service? (a) The operator of a...

  12. 36 CFR 3.5 - Do I have to report an accident involving a vessel to the National Park Service?

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... accident involving a vessel to the National Park Service? 3.5 Section 3.5 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.5 Do I have to report an accident involving a vessel to the National Park Service? (a) The operator of a...

  13. 36 CFR 3.5 - Do I have to report an accident involving a vessel to the National Park Service?

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... accident involving a vessel to the National Park Service? 3.5 Section 3.5 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.5 Do I have to report an accident involving a vessel to the National Park Service? (a) The operator of a...

  14. 36 CFR 3.5 - Do I have to report an accident involving a vessel to the National Park Service?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... accident involving a vessel to the National Park Service? 3.5 Section 3.5 Parks, Forests, and Public Property NATIONAL PARK SERVICE, DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.5 Do I have to report an accident involving a vessel to the National Park Service? (a) The operator of a...

  15. [Concentration of prostaglandins and cyclic adenosine-3',5'-monophosphate in the tissues of rats].

    PubMed

    Komissarenko, V P; Slavnov, V N; Epsheĭn, E V; Malinkovich, V D

    1977-04-01

    The content of prostaglandines (PG) and cyclic 3',5'-adenosine monphosphate (cAMP) was investigated in rat tissues by the radioisotopic method of competitive binding. Maximum quantities of both PG and cAMP were revealed in the same most actively functioning organs: the brain, incretory glands, small intestine. Fatty tissue showed minimum quantities of these substances. Results indicate a close functional relationship between the PG synthesis and adenylatecyclase activity in the body tissues.

  16. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, Betty W.

    1986-01-01

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the present invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve much of the TATB, but readily dissolves these explosives.

  17. Spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB

    DOEpatents

    Harris, B.W.

    1984-11-29

    A simple, sensitive and specific spot test for 1,3,5-triamino-2,4,6-trinitrobenzene, TATB, is described. Upon the application of the composition of matter of the subject invention to samples containing in excess of 0.1 mg of this explosive, a bright orange color results. Interfering species such as TNT and Tetryl can be removed by first treating the sample with a solvent which does not dissolve the TATB, but readily dissolves these interfering explosives.

  18. Biodegradation of Nitro-Substituted Explosives 2,4,6-Trinitrotoluene, Hexahydro-1,3,5-Trinitro-1,3,5-Triazine, and Octahydro-1,3,5,7-Tetranitro-1,3,5-Tetrazocine by a Phytosymbiotic Methylobacterium sp. Associated with Poplar Tissues (Populus deltoides × nigra DN34)

    PubMed Central

    Van Aken, Benoit; Yoon, Jong Moon; Schnoor, Jerald L.

    2004-01-01

    A pink-pigmented symbiotic bacterium was isolated from hybrid poplar tissues (Populus deltoides × nigra DN34). The bacterium was identified by 16S and 16S-23S intergenic spacer ribosomal DNA analysis as a Methylobacterium sp. (strain BJ001). The isolated bacterium was able to use methanol as the sole source of carbon and energy, which is a specific attribute of the genus Methylobacterium. The bacterium in pure culture was shown to degrade the toxic explosives 2,4,6-trinitrotoluene (TNT), hexahydro-1,3,5-trinitro-1,3,5-triazene (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5-tetrazocine (HMX). [U-ring-14C]TNT (25 mg liter−1) was fully transformed in less than 10 days. Metabolites included the reduction derivatives amino-dinitrotoluenes and diamino-nitrotoluenes. No significant release of 14CO2 was recorded from [14C]TNT. In addition, the isolated methylotroph was shown to transform [U-14C]RDX (20 mg liter−1) and [U-14C]HMX (2.5 mg liter−1) in less than 40 days. After 55 days of incubation, 58.0% of initial [14C]RDX and 61.4% of initial [14C]HMX were mineralized into 14CO2. The radioactivity remaining in solution accounted for 12.8 and 12.7% of initial [14C]RDX and [14C]HMX, respectively. Metabolites detected from RDX transformation included a mononitroso RDX derivative and a polar compound tentatively identified as methylenedinitramine. Since members of the genus Methylobacterium are distributed in a wide diversity of natural environments and are very often associated with plants, Methylobacterium sp. strain BJ001 may be involved in natural attenuation or in situ biodegradation (including phytoremediation) of explosive-contaminated sites. PMID:14711682

  19. Purification and characterization of DNase VII, a 3'. -->. 5'-directed exonuclease from human placenta

    SciTech Connect

    Hollis, G.F.; Grossman, L.

    1981-01-01

    An exonuclease, DNase VII, has been purified 6000-fold from human placenta. The enzyme has an apparent molecular weight of 43,000, requires Mg/sup 2 +/ for activity, and has a pH optimum of 7.8. The enzyme hydrolyzes single-stranded and nicked duplex DNA at the same rate proceeding in a 3' ..-->.. 5' direction liberating 5'-mononucleotides. It does not measurably hydrolyze polyribonucleotides.

  20. Structure and applications of metal-organic framework based on cyanide and 3,5-dichloropyridine

    NASA Astrophysics Data System (ADS)

    Etaiw, Safaa El-din H.; El-bendary, Mohamed M.

    2013-06-01

    The reaction of the aqueous/acetonitrile solutions of K3[Cu(CN)4] and 3,5-dichloropyridine (3,5-dClpy), in the presence of Me3SnCl affords a new metal-organic framework (MOF), 3∞[(CuCN)2·(3,5-dClpy)2], 1. The structure of the MOF 1 was characterized by IR, UV-visible, TGA and X-ray single crystal analysis. The structure of MOF 1 consists of CuCN building blocks which are connected by CN group forming 1D-zig-zag chains. Each chain is bridged to another chain by hydrogen bonding organizing 2D-sheets. The structure of 1 is further close packed by hydrogen bonds, π-π stacking and lp-π interactions creating 3D-network. The emission spectra and the thermodynamic parameters from TGA of the MOF 1 were discussed. The MOF 1 was used as heterogeneous catalyst for the oxidative discoloration of methylene blue dye (MB) by dilute solution of hydrogen peroxide as oxidant. The in vitro cytotoxic activity has been evaluated against the human breast cancer cell lines MCF-7. The cytotoxic effect of the MOF 1 on the viability of MCF-7 cells was determined by MTT assay.