WorldWideScience

Sample records for strong cn bands

  1. On the Adjacent Strong Equitable Edge Coloring of Pn ∨ Pn, Pn ∨ Cn and CnCn

    OpenAIRE

    Liu Jun; Zhao Chuan Cheng; Yao Shu Xia; Guo Ren Zhi; Yue Qiu Ju

    2016-01-01

    A proper edge coloring of graph G is called equitable adjacent strong edge coloring if colored sets from every two adjacent vertices incident edge are different,and the number of edges in any two color classes differ by at most one,which the required minimum number of colors is called the adjacent strong equitable edge chromatic number. In this paper, we discuss the adjacent strong equitable edge coloring of join-graphs about Pn ∨ Pn, Pn ∨ Cn and CnCn.

  2. The ν 1Band System of H-CC-CN (Cyanoacetylene)

    Science.gov (United States)

    Winther, F.; Klee, S.; Mellau, G.; Naı̈m, S.; Mbosei, L.; Fayt, A.

    1996-02-01

    The ν1band system of cyanoacetylene (H-CC-CN) has been observed with an effective resolution of 0.006 cm-1. ν1= 3327.37085(3) cm-1,B1= 0.15149762(2) cm-1,D1= 1.8065(3) × 10-8cm-1. Several hot bands from the statesv5= 1,v6= 1,v7= 1, 2 (l= 0 and 2), 3 (l= 1 and 3), and 4 (l= 0 and 2),v6=v7= 1 (l= 0 and 2), andv6= 1 andv7= 2 (l= 3) have also been observed and analyzed. Many bands show strong local perturbations due to interactions with states which are combinations of the modes 4, 5, 6, and 7. These perturbing states are also described quantitatively, and rovibrational constants are given.

  3. Monitoring of the future strong Vrancea events by using the CN formal earthquake prediction algorithm

    International Nuclear Information System (INIS)

    Moldoveanu, C.L.; Novikova, O.V.; Panza, G.F.; Radulian, M.

    2003-06-01

    The preparation process of the strong subcrustal events originating in Vrancea region, Romania, is monitored using an intermediate-term medium-range earthquake prediction method - the CN algorithm (Keilis-Borok and Rotwain, 1990). We present the results of the monitoring of the preparation of future strong earthquakes for the time interval from January 1, 1994 (1994.1.1), to January 1, 2003 (2003.1.1) using the updated catalogue of the Romanian local network. The database considered for the CN monitoring of the preparation of future strong earthquakes in Vrancea covers the period from 1966.3.1 to 2003.1.1 and the geographical rectangle 44.8 deg - 48.4 deg N, 25.0 deg - 28.0 deg E. The algorithm correctly identifies, by retrospective prediction, the TJPs for all the three strong earthquakes (Mo=6.4) that occurred in Vrancea during this period. The cumulated duration of the TIPs represents 26.5% of the total period of time considered (1966.3.1-2003.1.1). The monitoring of current seismicity using the algorithm CN has been carried out since 1994. No strong earthquakes occurred from 1994.1.1 to 2003.1.1 but the CN declared an extended false alarm from 1999.5.1 to 2000.11.1. No alarm has currently been declared in the region (on January 1, 2003), as can be seen from the TJPs diagram shown. (author)

  4. Strongly coupled band in 140Gd

    International Nuclear Information System (INIS)

    Falla-Sotelo, F.; Oliveira, J.R.B.; Rao, M.N.

    2005-01-01

    Several high-K states are known to exist in the mass 130-140 region. For the N=74 even-even isotopes, Kπ = 8 - isomers, with lifetimes ranging from ns to ms, are known in 128 Xe, 130 Ba, 132 Ce, 134 Nd, 136 Sm, and 138 Gd[. In 140 Gd, we have observed for the first time a band also based on an Iπ = 8 - state. This could be the first case of a Kπ = 8 - state observed in an N=76 even-even isotope. The systematics of the Kπ = 8 - isomeric states in N=74 isotopes has been studied by A.M. Bruce et al. These states decay towards the K = 0 ground state band, and the transitions are K-forbidden. The 140 Gd case presents strong similarities but also some significant differences with relation to the N=74 isotopes. We propose the same configuration but with larger deformation in 140 Gd

  5. Strongly coupled band in {sup 140}Gd

    Energy Technology Data Exchange (ETDEWEB)

    Falla-Sotelo, F.; Oliveira, J.R.B.; Rao, M.N. [Instituto de Fisica, Universidade de Sao Paulo, Sao Paulo (Brazil)] (and others)

    2005-07-01

    Several high-K states are known to exist in the mass 130-140 region. For the N=74 even-even isotopes, K{pi} = 8{sup -} isomers, with lifetimes ranging from ns to ms, are known in {sup 128}Xe, {sup 130}Ba, {sup 132}Ce, {sup 134}Nd, {sup 136}Sm, and {sup 138}Gd[. In {sup 140}Gd, we have observed for the first time a band also based on an I{pi} = 8{sup -} state. This could be the first case of a K{pi} = 8{sup -} state observed in an N=76 even-even isotope. The systematics of the K{pi} = 8{sup -} isomeric states in N=74 isotopes has been studied by A.M. Bruce et al. These states decay towards the K = 0 ground state band, and the transitions are K-forbidden. The {sup 140}Gd case presents strong similarities but also some significant differences with relation to the N=74 isotopes. We propose the same configuration but with larger deformation in {sup 140}Gd.

  6. CN earthquake prediction algorithm and the monitoring of the future strong Vrancea events

    International Nuclear Information System (INIS)

    Moldoveanu, C.L.; Radulian, M.; Novikova, O.V.; Panza, G.F.

    2002-01-01

    The strong earthquakes originating at intermediate-depth in the Vrancea region (located in the SE corner of the highly bent Carpathian arc) represent one of the most important natural disasters able to induce heavy effects (high tool of casualties and extensive damage) in the Romanian territory. The occurrence of these earthquakes is irregular, but not infrequent. Their effects are felt over a large territory, from Central Europe to Moscow and from Greece to Scandinavia. The largest cultural and economical center exposed to the seismic risk due to the Vrancea earthquakes is Bucharest. This metropolitan area (230 km 2 wide) is characterized by the presence of 2.5 million inhabitants (10% of the country population) and by a considerable number of high-risk structures and infrastructures. The best way to face strong earthquakes is to mitigate the seismic risk by using the two possible complementary approaches represented by (a) the antiseismic design of structures and infrastructures (able to support strong earthquakes without significant damage), and (b) the strong earthquake prediction (in terms of alarm intervals declared for long, intermediate or short-term space-and time-windows). The intermediate term medium-range earthquake prediction represents the most realistic target to be reached at the present state of knowledge. The alarm declared in this case extends over a time window of about one year or more, and a space window of a few hundreds of kilometers. In the case of Vrancea events the spatial uncertainty is much less, being of about 100 km. The main measures for the mitigation of the seismic risk allowed by the intermediate-term medium-range prediction are: (a) verification of the buildings and infrastructures stability and reinforcement measures when required, (b) elaboration of emergency plans of action, (c) schedule of the main actions required in order to restore the normality of the social and economical life after the earthquake. The paper presents the

  7. Trends in Strong Chemical Bonding in C2, CN, CN-, CO, N2, NO, NO+, and O2

    DEFF Research Database (Denmark)

    Kepp, Kasper Planeta

    2017-01-01

    The strong chemical bonds between C, N, and O play a central role in chemistry, and their formation and cleavage are critical steps in very many catalytic processes. The close-lying molecular orbital energies and large correlation effects pose a challenge to electronic structure calculations and ...

  8. Near-infrared Spectroscopic Observations of Comet C/2013 R1 (Lovejoy) by WINERED: CN Red-system Band Emission

    Energy Technology Data Exchange (ETDEWEB)

    Shinnaka, Yoshiharu; Yasui, Chikako; Izumi, Natsuko [National Astronomical Observatory of Japan, 2-21-1 Osawa, Mitaka, Tokyo 181-8588 (Japan); Kawakita, Hideyo; Kondo, Sohei; Ikeda, Yuji; Kobayashi, Naoto; Hamano, Satoshi; Sameshima, Hiroaki; Fukue, Kei; Matsunaga, Noriyuki; Otsubo, Shogo; Takenaka, Keiichi; Watase, Ayaka; Kawanishi, Takafumi; Nakanishi, Kenshi; Nakaoka, Tetsuya [Laboratory of Infrared High-resolution Spectroscopy, Koyama Astronomical Observatory, Kyoto Sangyo University, Motoyama, Kamigamo, Kita-ku, Kyoto 603-8555 (Japan); Mizumoto, Misaki, E-mail: yoshiharu.shinnaka@nao.ac.jp, E-mail: kawakthd@cc.kyoto-su.ac.jp [Department of Astronomy, School of Science, The University of Tokyo, Bunkyo-ku, Tokyo 113-0033 (Japan)

    2017-08-01

    Although high-resolution spectra of the CN red-system band are considered useful in cometary sciences, e.g., in the study of isotopic ratios of carbon and nitrogen in cometary volatiles, there have been few reports to date due to the lack of high-resolution ( R  ≡  λ /Δ λ  > 20,000) spectrographs in the near-infrared region around ∼1 μ m. Here, we present the high-resolution emission spectrum of the CN red-system band in comet C/2013 R1 (Lovejoy), acquired by the near-infrared high-resolution spectrograph WINERED mounted on the 1.3 m Araki telescope at the Koyama Astronomical Observatory, Kyoto, Japan. We applied our fluorescence excitation models for CN, based on modern spectroscopic studies, to the observed spectrum of comet C/2013 R1 (Lovejoy) to search for CN isotopologues ({sup 13}C{sup 14}N and {sup 12}C{sup 15}N). We used a CN fluorescence excitation model involving both a “pure” fluorescence excitation model for the outer coma and a “fully collisional” fluorescence excitation model for the inner coma region. Our emission model could reproduce the observed {sup 12}C{sup 14}N red-system band of comet C/2013 R1 (Lovejoy). The derived mixing ratio between the two excitation models was 0.94(+0.02/−0.03):0.06(+0.03/−0.02), corresponding to the radius of the collision-dominant region of ∼800–1600 km from the nucleus. No isotopologues were detected. The observed spectrum is consistent, within error, with previous estimates in comets of {sup 12}C/{sup 13}C (∼90) and {sup 14}N/{sup 15}N (∼150).

  9. Surface correlation effects in two-band strongly correlated slabs.

    Science.gov (United States)

    Esfahani, D Nasr; Covaci, L; Peeters, F M

    2014-02-19

    Using an extension of the Gutzwiller approximation for an inhomogeneous system, we study the two-band Hubbard model with unequal band widths for a slab geometry. The aim is to investigate the mutual effect of individual bands on the spatial distribution of quasi-particle weight and charge density, especially near the surface of the slab. The main effect of the difference in band width is the presence of two different length scales corresponding to the quasi-particle profile of each band. This is enhanced in the vicinity of the critical interaction of the narrow band where an orbitally selective Mott transition occurs and a surface dead layer forms for the narrow band. For the doped case, two different regimes of charge transfer between the surface and the bulk of the slab are revealed. The charge transfer from surface/center to center/surface depends on both the doping level and the average relative charge accumulated in each band. Such effects could also be of importance when describing the accumulation of charges at the interface between structures made of multi-band strongly correlated materials.

  10. Strong overtones and combination bands in ultraviolet resonance Raman spectroscopy

    NARCIS (Netherlands)

    Efremov, E.V.; Ariese, F.; Mank, A.J.G.; Gooijer, C.

    2006-01-01

    Ultraviolet resonance Raman spectroscopy is carried out using a continuous wave frequency-doubled argon ion laser operated at 229, 244, and 257 nm in order to characterize the overtones and combination bands for several classes of organic compounds in liquid solutions. Contrary to what is generally

  11. Strongly correlated impurity band superconductivity in diamond: X-ray spectroscopic evidence

    Directory of Open Access Journals (Sweden)

    G. Baskaran

    2006-01-01

    Full Text Available In a recent X-ray absorption study in boron doped diamond, Nakamura et al. have seen a well isolated narrow boron impurity band in non-superconducting samples and an additional narrow band at the chemical potential in a superconducting sample. We interpret the beautiful spectra as evidence for upper Hubbard band of a Mott insulating impurity band and an additional metallic 'mid-gap band' of a conducting 'self-doped' Mott insulator. This supports the basic framework of a recent theory of the present author of strongly correlated impurity band superconductivity (impurity band resonating valence bond, IBRVB theory in a template of a wide-gap insulator, with no direct involvement of valence band states.

  12. Spectra and relaxation dynamics of the pseudohalide (PS) vibrational bands for Ru(bpy)2(PS)2 complexes, PS = CN, NCS and N3

    International Nuclear Information System (INIS)

    Compton, Ryan; Gerardi, Helen K.; Weidinger, Daniel; Brown, Douglas J.; Dressick, Walter J.; Heilweil, Edwin J.; Owrutsky, Jeffrey C.

    2013-01-01

    Highlights: ► Static and transient infrared spectroscopy of pseudohalide bipyridine ruthenium complexes. ► Vibrational energy relaxes faster for the azide than the thiocyanate and cyanide analogs. ► Intramolecular vibrational relaxation is prevalent in cis-Ru(bpy) 2 (N 3 ) 2 . - Abstract: Static and transient infrared spectroscopy were used to investigate cis-Ru(bpy) 2 (N 3 ) 2 (bpy = 2,2′-bipyridine), cis-Ru(bpy) 2 (NCS) 2 , and cis-Ru(bpy) 2 (CN) 2 in solution. The NC stretching IR band for cis-Ru(bpy) 2 (NCS) 2 appears at higher frequency (∼2106 cm −1 in DMSO) than for the free NCS − anion while the IR bands for the azide and cyanide complexes are closer to those of the respective free anions. The vibrational energy relaxation (VER) lifetime for the azide complex is found to be much shorter (∼5 ps) than for either the NCS or CN species (both ∼70 ps in DMSO) and the lifetimes resemble those for each corresponding free anion in solution. However, for cis-Ru(bpy) 2 (N 3 ) 2 , it is determined that the transition frequency depends more on the solvent than the VER lifetime implying that intramolecular vibrational relaxation is predominant over solvent energy-extracting interactions. These results are compared to the behavior of other related metal complexes in solution

  13. Strongly reduced band gap in a correlated insulator in close proximity to a metal

    NARCIS (Netherlands)

    Hesper, R.; Tjeng, L.H; Sawatzky, G.A

    1997-01-01

    Using a combination of photoelectron and inverse photoelectron spectroscopy, we show that the band gap in a monolayer of C-60 on a Ag surface is strongly reduced from the solid C-60 surface value. We argue that this is a result of the reduction of the on-site molecular Coulomb interaction due to the

  14. Non-equilibrium reaction and relaxation dynamics in a strongly interacting explicit solvent: F + CD{sub 3}CN treated with a parallel multi-state EVB model

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, David R., E-mail: drglowacki@gmail.com [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Department of Computer Science, University of Bristol, Bristol BS8 1UB (United Kingdom); PULSE Institute and Department of Chemistry, Stanford University, Stanford, California 94305 (United States); SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Orr-Ewing, Andrew J. [School of Chemistry, University of Bristol, Bristol BS8 1TS (United Kingdom); Harvey, Jeremy N. [Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Heverlee (Belgium)

    2015-07-28

    We describe a parallelized linear-scaling computational framework developed to implement arbitrarily large multi-state empirical valence bond (MS-EVB) calculations within CHARMM and TINKER. Forces are obtained using the Hellmann-Feynman relationship, giving continuous gradients, and good energy conservation. Utilizing multi-dimensional Gaussian coupling elements fit to explicitly correlated coupled cluster theory, we built a 64-state MS-EVB model designed to study the F + CD{sub 3}CN → DF + CD{sub 2}CN reaction in CD{sub 3}CN solvent (recently reported in Dunning et al. [Science 347(6221), 530 (2015)]). This approach allows us to build a reactive potential energy surface whose balanced accuracy and efficiency considerably surpass what we could achieve otherwise. We ran molecular dynamics simulations to examine a range of observables which follow in the wake of the reactive event: energy deposition in the nascent reaction products, vibrational relaxation rates of excited DF in CD{sub 3}CN solvent, equilibrium power spectra of DF in CD{sub 3}CN, and time dependent spectral shifts associated with relaxation of the nascent DF. Many of our results are in good agreement with time-resolved experimental observations, providing evidence for the accuracy of our MS-EVB framework in treating both the solute and solute/solvent interactions. The simulations provide additional insight into the dynamics at sub-picosecond time scales that are difficult to resolve experimentally. In particular, the simulations show that (immediately following deuterium abstraction) the nascent DF finds itself in a non-equilibrium regime in two different respects: (1) it is highly vibrationally excited, with ∼23 kcal mol{sup −1} localized in the stretch and (2) its post-reaction solvation environment, in which it is not yet hydrogen-bonded to CD{sub 3}CN solvent molecules, is intermediate between the non-interacting gas-phase limit and the solution-phase equilibrium limit. Vibrational

  15. Non-equilibrium reaction and relaxation dynamics in a strongly interacting explicit solvent: F + CD3CN treated with a parallel multi-state EVB model.

    Science.gov (United States)

    Glowacki, David R; Orr-Ewing, Andrew J; Harvey, Jeremy N

    2015-07-28

    We describe a parallelized linear-scaling computational framework developed to implement arbitrarily large multi-state empirical valence bond (MS-EVB) calculations within CHARMM and TINKER. Forces are obtained using the Hellmann-Feynman relationship, giving continuous gradients, and good energy conservation. Utilizing multi-dimensional Gaussian coupling elements fit to explicitly correlated coupled cluster theory, we built a 64-state MS-EVB model designed to study the F + CD3CN → DF + CD2CN reaction in CD3CN solvent (recently reported in Dunning et al. [Science 347(6221), 530 (2015)]). This approach allows us to build a reactive potential energy surface whose balanced accuracy and efficiency considerably surpass what we could achieve otherwise. We ran molecular dynamics simulations to examine a range of observables which follow in the wake of the reactive event: energy deposition in the nascent reaction products, vibrational relaxation rates of excited DF in CD3CN solvent, equilibrium power spectra of DF in CD3CN, and time dependent spectral shifts associated with relaxation of the nascent DF. Many of our results are in good agreement with time-resolved experimental observations, providing evidence for the accuracy of our MS-EVB framework in treating both the solute and solute/solvent interactions. The simulations provide additional insight into the dynamics at sub-picosecond time scales that are difficult to resolve experimentally. In particular, the simulations show that (immediately following deuterium abstraction) the nascent DF finds itself in a non-equilibrium regime in two different respects: (1) it is highly vibrationally excited, with ∼23 kcal mol(-1) localized in the stretch and (2) its post-reaction solvation environment, in which it is not yet hydrogen-bonded to CD3CN solvent molecules, is intermediate between the non-interacting gas-phase limit and the solution-phase equilibrium limit. Vibrational relaxation of the nascent DF results in a spectral

  16. Strong RFI observed in protected 21 cm band at Zurich observatory, Switzerland

    Science.gov (United States)

    Monstein, C.

    2014-03-01

    While testing a new antenna control software tool, the telescope was moved to the most western azimuth position pointing to our own building. While de-accelerating the telescope, the spectrometer showed strong broadband radio frequency interference (RFI) and two single-frequency carriers around 1412 and 1425 MHz, both of which are in the internationally protected band. After lengthy analysis it was found out, that the Webcam AXIS2000 was the source for both the broadband and single-frequency interference. Switching off the Webcam solved the problem immediately. So, for future observations of 21 cm radiation, all nearby electronics has to be switched off. Not only the Webcam but also all unused PCs, printers, networks, monitors etc.

  17. Gamma spectroscopical studies of strongly deformed rotational bands in 73Br and 79Sr

    International Nuclear Information System (INIS)

    Heese, J.

    1989-01-01

    In the framework of this thesis the excitation structures of the nuclei 73 Br and 79 Sr were studied. For the population of high-spin states the reactions 40 Ca( 36 Ar,3p) 73 Br, -58 Ni( 24 Mg,2αp) 73 Br and 58 Ni( 24 Mg,2pn) 79 Sr were used. The level scheme of 73 Br could be extended by γγ coincidence measurements by 18 new states up to the spins 45/2 + respectively 45/2 - . DSA lifetime measurements yielded information about the deformations of the observed rotational bands. The conversion coefficients of the low-energetic transitions in the range of the excitation spectrum below 500 keV were determined and allowed the assignments of spins and parities. Furthermore the converted decay of the 27-keV state was observed for the first time, from the measured intensities of the electron line the lifetime of this state was estimated to 1.1 ≤ τ ≤ 9.1 μs. The measurement of the lifetime and the g factor of the isomeric 240-keV state confirmed the already known spin values and allowed statements on the particle structure. Lifetime measurements in 79 Sr were performed up to the states 21/2 + and 17/2 - . They yielded informations on E2 and M1 transition strengthened in the rotational bands. The transition strengths calculated from the lifetimes show that both nuclei are strongly prolate deformed. The sign of the deformation could be concluded in the case of 73 Br from the observed band structure, in 79 Sr it was calculated from E2/M1 mixing ratios. The E2-transition strengths show a reduction in both nuclei in the region of the g 9/2 proton alignment. Alignment effects in the rotational bands were discussed in the framework of the cranked shell model. Microscopical calculations in the Hartree-Fock-Bogolyubov cranking model with a deformed Woods-Saxon potential were performed. (orig./HSI) [de

  18. Large photonic band gaps and strong attenuations of two-segment-connected Peano derivative networks

    International Nuclear Information System (INIS)

    Lu, Jian; Yang, Xiangbo; Zhang, Guogang; Cai, Lianzhang

    2011-01-01

    In this Letter, based on ancient Peano curves we construct four kinds of interesting Peano derivative networks composed of one-dimensional (1D) waveguides and investigate the optical transmission spectra and photonic attenuation behavior of electromagnetic (EM) waves in one- and two-segment-connected networks. It is found that for some two-segment-connected networks large photonic band gaps (PBGs) can be created and the widths of large PBGs can be controlled by adjusting the matching ratio of waveguide length and are insensitive to generation number. Diamond- and hexagon-Peano networks are good selectable structures for the designing of optical devices with large PBG(s) and strong attenuation(s). -- Highlights: → Peano and Peano derivative networks composed of 1D waveguides are designed. → Large PBGs with strong attenuations have been created by these fractal networks. → New approach for designing optical devices with large PBGs is proposed. → Diamond- and hexagon-Peano networks with d2:d1=2:1 are good selectable structures.

  19. Band Gap Distortion in Semiconductors Strongly Driven by Intense Mid-Infrared Laser Fields

    Science.gov (United States)

    Kono, J.; Chin, A. H.

    2000-03-01

    Crystalline solids non-resonantly driven by intense time-periodic electric fields are predicted to exhibit unusual band-gap distortion.(e.g., Y. Yacoby, Phys. Rev. 169, 610 (1968); L.C.M. Miranda, Solid State Commun. 45, 783 (1983); J.Z. Kaminski, Acta Physica Polonica A 83, 495(1993).) Such non-perturbative effects have not been observed to date because of the unavoidable sample damage due to the very high intensity required using conventional lasers ( 1 eV photon energy). Here, we report the first clear evidence of laser-induced bandgap shrinkage in semiconductors under intense mid-infrared (MIR) laser fields. The use of long-wavelength light reduces the required intensity and prohibits strong interband absorption, thereby avoiding the damage problem. The significant sub-bandgap absorption persists only during the existence of the MIR laser pulse, indicating the virtual nature of the effect. We show that this particular example of non-perturbative behavior, known as the dynamical Franz-Keldysh effect, occurs when the effective ponderomotive potential energy is comparable to the photon energy of the applied field. This work was supported by ONR, NSF, JST and NEDO.

  20. Strong temperature effect on the sizes of the Cooper pairs in a two-band superconductor

    Science.gov (United States)

    Örd, Teet; Rägo, Küllike; Vargunin, Artjom; Litak, Grzegorz

    2018-01-01

    We study the temperature dependencies of the mean sizes of the Cooper pairs in a two-band BCS-type s-wave superconductivity model with coupling cut-off in the momentum space. It is found that, in contrast to single-band systems, the size of Cooper pairs in the weaker superconductivity band can significantly decrease with a temperature increase due to an interband proximity effect. The relevant spatial behaviour of the wave functions of the Cooper pairs is analyzed. The results also indicate a possibility that the size of Cooper pairs in two-band systems may increase with an increase in temperature.

  1. Vibrational emission analysis of the CN molecules in laser-induced breakdown spectroscopy of organic compounds

    Energy Technology Data Exchange (ETDEWEB)

    Fernández-Bravo, Ángel; Delgado, Tomás; Lucena, Patricia; Laserna, J. Javier, E-mail: laserna@uma.es

    2013-11-01

    Laser-induced breakdown spectroscopy (LIBS) of organic materials is based on the analysis of atomic and ionic emission lines and on a few molecular bands, the most important being the CN violet system and the C{sub 2} Swan system. This paper is focused in molecular emission of LIBS plasmas based on the CN (B{sup 2}Σ–X{sup 2}Σ) band, one of the strongest emissions appearing in all carbon materials when analyzed in air atmosphere. An analysis of this band with sufficient spectral resolution provides a great deal of information on the molecule, which has revealed that valuable information can be obtained from the plume chemistry and dynamics affecting the excitation mechanisms of the molecules. The vibrational emission of this molecular band has been investigated to establish the dependence of this emission on the molecular structure of the materials. The paper shows that excitation/emission phenomena of molecular species observed in the plume depend strongly on the time interval selected and on the irradiance deposited on the sample surface. Precise time resolved LIBS measurements are needed for the observation of distinctive CN emission. For the organic compounds studied, larger differences in the behavior of the vibrational emission occur at early stages after plasma ignition. Since molecular emission is generally more complex than that involving atomic emission, local plasma conditions as well as plume chemistry may induce changes in vibrational emission of molecules. As a consequence, alterations in the distribution of the emissions occur in terms of relative intensities, being sensitive to the molecular structure of every single material. - Highlights: • Vibrational emission of CN species in laser-induced plasmas has been investigated. • Distribution of vibrational emission of CN has been found to be time dependent. • Laser irradiance affects the vibrational distribution of the CN molecules. • Plume chemistry controls the excitation mechanisms of CN

  2. Strongly reduced band gap in NiMn2O4 due to cation exchange

    International Nuclear Information System (INIS)

    Huang, Jhih-Rong; Hsu, Han; Cheng, Ching

    2014-01-01

    NiMn 2 O 4 is extensively used as a basis material for temperature sensors due to its negative temperature coefficient of resistance (NTCR), which is commonly attributed to the hopping mechanism involving coexisting octahedral-site Mn 4+ and Mn 3+ . Using density-functional theory + Hubbard U calculations, we identify a ferrimagnetic inverse spinel phase as the collinear ground state of NiMn 2 O 4 . By a 12.5% cation exchange, a mixed phase with slightly higher energy can be constructed, accompanied by the formation of an impurity-like band in the original 1 eV band gap. This impurity-like band reduces the gap to 0.35 eV, suggesting a possible source of NTCR. - Highlights: • Density functional based calculations were used to study collinear phase of NiMn 2 O 4 . • The ground-state structure is a ferrimagnetic inverse spinel phase. • The tetrahedral and octahedral Mn cations have ferromagnetic interactions. • A 12.5% cation exchange introduces an impurity-like band in the original 1 eV gap. • The 0.35 eV gap suggests a source of negative temperature coefficient of resistance

  3. Correlations between Strong Range Spread-F and GPS L-Band Scintillations Observed in Hainan in 2004

    International Nuclear Information System (INIS)

    Guo-Jun, Wang; Jian-Kui, Shi; She-Ping, Shang; Xiao, Wang

    2009-01-01

    Data from the DPS-4 digisonde and the GPS L-band ionospheric scintillation monitor are employed to study the correlations between strong range spread-F (SSF) and GPS L-band scintillations observed in the ionosphere over Hainan Island, China (19.5°N, 109.1°E geogr., dip lat. 9°N) in 2004. The SSF in the ionogram is different from the general range spread-F because it extends in frequency well beyond FoF2 and makes FoF2 difficult to be determined. The observations show that the SSF phenomenon is frequently accompanied by the occurrence of GPS L-band scintillations. The SSF and GPS L-band scintillations occur frequently in the equinoctial months (March, April, September, and October), but rarely in the winter (January, February, November, and December) and summer (May–August); especially, occurrence variations of the SSF and GPS L-band scintillations nearly have a same trend. The SSF and scintillations may be associated with the occurrence of topside plasma bubbles and could be explained by the generalized Rayleigh–Taylor instability

  4. Beyond band termination in 157Er and the search for wobbling excitations in strongly deformed 174Hf

    International Nuclear Information System (INIS)

    Riley, M A; Djongolov, M K; Evans, A O

    2005-01-01

    High-spin terminating bands in heavy nuclei were first identified in nuclei around 158 Er 90 . While examples of special terminating states have been identified in a number of erbium isotopes, almost nothing is known about the states lying beyond band termination. In the present work the high-spin structure of 157 Er has been studied using the Gammasphere spectrometer. The subject of triaxial superdeformation and 'wobbling' modes in Lu nuclei has rightly attracted a great deal of attention. Very recently, four strongly or superdeformed (SD) sequences have been observed in 174 Hf and ultimate cranker calculations predict such structures may have significant triaxial deformation. We have performed two experiments in an attempt to verify the possible triaxial nature of these bands. A lifetime measurement was performed to confirm the large (and similar) deformation of the bands. In addition, a high-statistics, thin-target experiment was run to search for linking transitions between the SD bands and possible wobbling modes

  5. Spectra and relaxation dynamics of the pseudohalide (PS) vibrational bands for Ru(bpy){sub 2}(PS){sub 2} complexes, PS = CN, NCS and N{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Compton, Ryan; Gerardi, Helen K. [Chemistry Division, Naval Research Laboratory, Washington, DC 20375 (United States); Weidinger, Daniel [SRA International, 4300 Fair Lakes Court, Fairfax, VA 22033 (United States); Brown, Douglas J. [Chemistry Department, US Naval Academy, Annapolis, MD 21402 (United States); Dressick, Walter J. [Center for Bio/Molecular Science and Engineering, Naval Research Laboratory, Washington, DC 20375 (United States); Heilweil, Edwin J. [Radiation and Biomolecular Physics Division, Physical Measurement Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Owrutsky, Jeffrey C., E-mail: Jeff.Owrutsky@nrl.navy.mil [Chemistry Division, Naval Research Laboratory, Washington, DC 20375 (United States)

    2013-08-30

    Highlights: ► Static and transient infrared spectroscopy of pseudohalide bipyridine ruthenium complexes. ► Vibrational energy relaxes faster for the azide than the thiocyanate and cyanide analogs. ► Intramolecular vibrational relaxation is prevalent in cis-Ru(bpy){sub 2}(N{sub 3}){sub 2}. - Abstract: Static and transient infrared spectroscopy were used to investigate cis-Ru(bpy){sub 2}(N{sub 3}){sub 2} (bpy = 2,2′-bipyridine), cis-Ru(bpy){sub 2}(NCS){sub 2}, and cis-Ru(bpy){sub 2}(CN){sub 2} in solution. The NC stretching IR band for cis-Ru(bpy){sub 2}(NCS){sub 2} appears at higher frequency (∼2106 cm{sup −1} in DMSO) than for the free NCS{sup −} anion while the IR bands for the azide and cyanide complexes are closer to those of the respective free anions. The vibrational energy relaxation (VER) lifetime for the azide complex is found to be much shorter (∼5 ps) than for either the NCS or CN species (both ∼70 ps in DMSO) and the lifetimes resemble those for each corresponding free anion in solution. However, for cis-Ru(bpy){sub 2}(N{sub 3}){sub 2}, it is determined that the transition frequency depends more on the solvent than the VER lifetime implying that intramolecular vibrational relaxation is predominant over solvent energy-extracting interactions. These results are compared to the behavior of other related metal complexes in solution.

  6. Vacuum instability, anomalous asymmetry effect, phase transition and band mixing in strongly deformed nuclei

    International Nuclear Information System (INIS)

    Lin, L.; Sperber, D.

    1976-01-01

    In two recent papers the instability of the quasi-particle vacuum was related to the high-spin anomaly in rotational nuclear states. The direct consequence of this fact is that the system will make a ''phase transition'' under that situation. Studying the induced rotational asymmetry effect, in the present paper another theoretical fact is discussed, which support this ''phase transition''. Furthermore, it is shown that when this ''phase transition'' occurs, in order to have a proper description of the system, a modification of the physical ground state is necessary which suggests a microscopic theory of band mixing for high spin anomaly in rotational nuclear states

  7. Light exiting from real photonic band gap crystals is diffuse and strongly directional

    NARCIS (Netherlands)

    Koenderink, A.F.; Vos, Willem L.

    2003-01-01

    Any photonic crystal is in practice periodic with some inevitable fabricational imperfections. We have measured angle-resolved transmission of photons that are multiply scattered by this disorder in strongly photonic crystals. Peculiar non-Lambertian distributions occur as a function of frequency:

  8. Strongly driven electron spins using a Ku band stripline electron paramagnetic resonance resonator

    Science.gov (United States)

    Yap, Yung Szen; Yamamoto, Hiroshi; Tabuchi, Yutaka; Negoro, Makoto; Kagawa, Akinori; Kitagawa, Masahiro

    2013-07-01

    This article details our work to obtain strong excitation for electron paramagnetic resonance (EPR) experiments by improving the resonator's efficiency. The advantages and application of strong excitation are discussed. Two 17 GHz transmission-type, stripline resonators were designed, simulated and fabricated. Scattering parameter measurements were carried out and quality factor were measured to be around 160 and 85. Simulation results of the microwave's magnetic field distribution are also presented. To determine the excitation field at the sample, nutation experiments were carried out and power dependence were measured using two organic samples at room temperature. The highest recorded Rabi frequency was rated at 210 MHz with an input power of about 1 W, which corresponds to a π/2 pulse of about 1.2 ns.

  9. Assessing the importance of frustration in a narrow-band strongly correlated electronic chain

    International Nuclear Information System (INIS)

    Lal, Siddhartha; Laad, Mukul S.

    2007-08-01

    We study a one-dimensional extended Hubbard model with longer-range Coulomb interactions at quarter-filling in the strong coupling limit. In this limit, we find the one dimensional transverse field Ising model (TFIM) to be the effective Hamiltonian governing the dynamics of the charge degrees of freedom. We find two different charge-ordered (CO) ground states as the strength of the longer range interactions is varied. At lower energies, these CO states drive two different spin-ordered ground states. A variety of response functions computed here bear a remarkable resemblance to recent experimental observations for organic TMTSF systems, and so we propose that these systems are proximate to a QCP associated with T = 0 charge order. (author)

  10. Strongly correlated quasi-one-dimensional bands: Ground states, optical absorption, and phonons

    International Nuclear Information System (INIS)

    Campbell, D.K.; Gammel, J.T.; Loh, E.Y. Jr.

    1989-01-01

    Using the Lanczos method for exact diagonalization on systems up to 14 sites, combined with a novel ''phase randomization'' technique for extracting more information from these small systems, we investigate several aspects of the one-dimensional Peierls-Hubbard Hamiltonian, in the context of trans-polyacetylene: the dependence of the ground state dimerization on the strength of the electron-electron interactions, including the effects of ''off-diagonal'' Coulomb terms generally ignored in the Hubbard model; the phonon vibrational frequencies and dispersion relations, and the optical absorption properties, including the spectrum of absorptions as a function of photon energy. These three different observables provide considerable insight into the effects of electron-electron interactions on the properties of real materials and thus into the nature of strongly correlated electron systems. 29 refs., 11 figs

  11. CN in dark clouds

    International Nuclear Information System (INIS)

    Churchwell, E.; Bieging, J.H.

    1983-01-01

    We have detected CN (N = 1--0) emission toward six locations in the Taurus dark cloud complex, but not toward L183 or B227. The two hyperfine components, F = 3/2--1/2 and F = 5/2--3/2 (of J = 3/2--1/2), have intensity ratios near unity toward four locations in Taurus, consistent with large line optical depths. CN column densities are found to be > or approx. =6 x 10 13 cm -2 in those directions where the hyperfine ratios are near unity. By comparing CN with NH 3 and C 18 O column densities, we find that the relative abundance of CN in the Taurus cloudlets is at least a factor of 10 greater than in L183. In this respect, CN fits the pattern of enhanced abundances of carbon-bearing molecules (in partricular the cyanopolyynes) in the Taurus cloudlets relative to similar dark clouds outside Taurus

  12. Strong Photonic-Band-Gap Effect on the Spontaneous Emission in 3D Lead Halide Perovskite Photonic Crystals.

    Science.gov (United States)

    Zhou, Xue; Li, Mingzhu; Wang, Kang; Li, Huizeng; Li, Yanan; Li, Chang; Yan, Yongli; Zhao, Yongsheng; Song, Yanlin

    2018-03-25

    Stimulated emission in perovskite-embedded polymer opal structures is investigated. A polymer opal structure is filled with a perovskite, and perovskite photonic crystals are prepared. The spontaneous emission of the perovskite embedded in the polymer opal structures exhibits clear signatures of amplified spontaneous emission (ASE) via gain modulation. The difference in refractive-index contrast between the perovskite and the polymer opal is large enough for retaining photonic-crystals properties. The photonic band gap has a strong effect on the fluorescence emission intensity and lifetime. The stimulated emission spectrum exhibits a narrow ASE rather than a wide fluorescence peak in the thin film. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Strongly coupled rotational band in Mg33

    Energy Technology Data Exchange (ETDEWEB)

    Richard, A. L.; Crawford, H. L.; Fallon, P.; Macchiavelli, A. O.; Bader, V. M.; Bazin, D.; Bowry, M.; Campbell, C. M.; Carpenter, M. P.; Clark, R. M.; Cromaz, M.; Gade, A.; Ideguchi, E.; Iwasaki, H.; Jones, M. D.; Langer, C.; Lee, I. Y.; Loelius, C.; Lunderberg, E.; Morse, C.; Rissanen, J.; Salathe, M.; Smalley, D.; Stroberg, S. R.; Weisshaar, D.; Whitmore, K.; Wiens, A.; Williams, S. J.; Wimmer, K.; Yamamato, T.

    2017-07-01

    The “Island of Inversion” at N~20 for the neon, sodium, and magnesium isotopes has long been an area of interest both experimentally and theoretically due to the subtle competition between 0p-0h and np-nh configurations leading to deformed shapes. However, the presence of rotational band structures, which are fingerprints of deformed shapes, have only recently been observed in this region. In this work, we report on a measurement of the low-lying level structure of 33Mg populated by a two-stage projectile fragmentation reaction and studied with GRETINA. The experimental level energies, ground state magnetic moment, intrinsic quadrupole moment, and γ-ray intensities show good agreement with the strong-coupling limit of a rotational model.

  14. Strongly coupled rotational band in Mg33

    Energy Technology Data Exchange (ETDEWEB)

    Richard, A. L. [Ohio Univ., Athens, OH (United States). Inst. for Nuclear and Particle Physics; Crawford, H. L. [Ohio Univ., Athens, OH (United States). Inst. for Nuclear and Particle Physics; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Fallon, P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Macchiavelli, A. O. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Bader, V. M. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Bazin, D. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab.; Bowry, M. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Campbell, C. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Carpenter, M. P. [Argonne National Lab. (ANL), Argonne, IL (United States). Physics Div.; Clark, R. M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Cromaz, M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Gade, A. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Ideguchi, E. [Osaka Univ. (Japan). RCNP; Iwasaki, H. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Jones, M. D. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Langer, C. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Lee, I. Y. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Loelius, C. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Lunderberg, E. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Morse, C. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Rissanen, J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Salathe, M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Smalley, D. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Stroberg, S. R. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Weisshaar, D. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Whitmore, K. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Michigan State Univ., East Lansing, MI (United States). Dept. of Physics and Astronomy; Wiens, A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Nuclear Science Div.; Williams, S. J. [Michigan State Univ., East Lansing, MI (United States). National Superconducting Cyclotron Lab; Wimmer, K. [Univ. of Tokyo (Japan). Dept. of Physics; Yamamato, T. [Osaka Univ. (Japan). RCNP

    2017-07-01

    The “island of inversion” at N≈20 for the neon, sodium, and magnesium isotopes has long been an area of interest both experimentally and theoretically due to the subtle competition between 0p-0h and np-nh configurations leading to deformed shapes. However, the presence of rotational band structures, which are fingerprints of deformed shapes, have only recently been observed in this region. In this work, we report on a measurement of the low-lying level structure of Mg33 populated by a two-stage projectile fragmentation reaction and studied with the Gamma Ray Energy Tracking In-Beam Nuclear Array (GRETINA). The experimental level energies, ground-state magnetic moment, intrinsic quadrupole moment, and γ-ray intensities show good agreement with the strong-coupling limit of a rotational model.

  15. A self-interference cancelling receiver for in-band full-duplex wireless with low distortion under cancellation of strong TX leakage

    NARCIS (Netherlands)

    van den Broek, Dirk-Jan; Klumperink, Eric A.M.; Nauta, Bram

    2015-01-01

    In-band full-duplex (FD) wireless communication, i.e. simultaneous transmission and reception at the same frequency, in the same channel, promises up to 2x spectral efficiency, along with advantages in higher network layers [1]. the main challenge is dealing with strong in-band leakage from the

  16. Feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS) to quantify iron-cyanide (Fe-CN) complexes in soil

    Science.gov (United States)

    Sut-Lohmann, Magdalena; Raab, Thomas

    2017-04-01

    Contaminated sites create a significant risk to human health, by poisoning drinking water, soil, air and as a consequence food. Continuous release of persistent iron-cyanide (Fe-CN) complexes from various industrial sources poses a high hazard to the environment and indicates the necessity to analyze considerable amount of samples. At the present time quantitative determination of Fe-CN concentration in soil usually requires a time consuming two step process: digestion of the sample (e.g., micro distillation system) and its analytical detection performed, e.g., by automated spectrophotometrical flow injection analysis (FIA). In order to determine the feasibility of diffuse reflectance infrared Fourier spectroscopy (DRIFTS) to quantify the Fe-CN complexes in soil matrix, 42 soil samples were collected (8 to 12.520 mg kg-1CN) indicating single symmetrical CN band in the range 2092 - 2084 cm-1. Partial least squares (PLS) calibration-validation model revealed IR response to CNtot exceeding 1268 mg kg-1 (limit of detection, LOD). Subsequently, leave-one-out cross-validation (LOO-CV) was performed on soil samples containing low CNtot (900 mg kg-1 resulted in LOD equal to 3494 mg kg-1. Our results indicate that spectroscopic data in combination with PLS statistics can efficiently be used to predict Fe-CN concentrations in soil. We conclude that the protocol applied in this study can strongly reduce the time and costs essential for the spatial and vertical screening of the site affected by complexed Fe-CN.

  17. Strong Energy-momentum Dispersion of Phonon Dressed Carriers in the Lightly Doped Band Insulator SrTiO3

    International Nuclear Information System (INIS)

    Meevasana, Warawat

    2010-01-01

    Much progress has been made recently in the study of the effects of electron-phonon (el-ph) coupling in doped insulators using angle resolved photoemission (ARPES), yielding evidence for the dominant role of el-ph interactions in underdoped cuprates. As these studies have been limited to doped Mott insulators, the important question arises how this compares with doped band insulators where similar el-ph couplings should be at work. The archetypical case is the perovskite SrTiO 3 (STO), well known for its giant dielectric constant of 10000 at low temperature, exceeding that of La 2 CuO 4 by a factor of 500. Based on this fact, it has been suggested that doped STO should be the archetypical bipolaron superconductor. Here we report an ARPES study from high-quality surfaces of lightly doped SrTiO 3 . Comparing to lightly doped Mott insulators, we find the signatures of only moderate electron-phonon coupling: a dispersion anomaly associated with the low frequency optical phonon with a λ(prime) ∼ 0.3 and an overall bandwidth renormalization suggesting an overall λ(prime) ∼ 0.7 coming from the higher frequency phonons. Further, we find no clear signatures of the large pseudogap or small polaron phenomena. These findings demonstrate that a large dielectric constant itself is not a good indicator of el-ph coupling and highlight the unusually strong effects of the el-ph coupling in doped Mott insulators.

  18. Unexpected alignment patterns in high-j intruder bands evidence for a strong residual neutron proton interaction?

    International Nuclear Information System (INIS)

    Wyss, R.; Johnson, A.; Royal Inst. of Tech., Stockholm

    1990-01-01

    The alignment of h 11/12 protons in νi 13/2 intruder bands in mass A = 130 region is investigated. The lack of a clear h 11/12 band crossing is compared with the alignment pattern of i 13/2 neutrons in πi 13/2 intruder bands in mass A = 180 region. The very smooth rise in angular momentum in the intruder bands is related to a possible neutron proton interaction between the single intruder orbital and the aligned two-quasiparticle configuration. 36 refs., 3 figs

  19. An Unusual Strong Visible-Light Absorption Band in Red Anatase TiO2 Photocatalyst Induced by Atomic Hydrogen-Occupied Oxygen Vacancies.

    Science.gov (United States)

    Yang, Yongqiang; Yin, Li-Chang; Gong, Yue; Niu, Ping; Wang, Jian-Qiang; Gu, Lin; Chen, Xingqiu; Liu, Gang; Wang, Lianzhou; Cheng, Hui-Ming

    2018-02-01

    Increasing visible light absorption of classic wide-bandgap photocatalysts like TiO 2 has long been pursued in order to promote solar energy conversion. Modulating the composition and/or stoichiometry of these photocatalysts is essential to narrow their bandgap for a strong visible-light absorption band. However, the bands obtained so far normally suffer from a low absorbance and/or narrow range. Herein, in contrast to the common tail-like absorption band in hydrogen-free oxygen-deficient TiO 2 , an unusual strong absorption band spanning the full spectrum of visible light is achieved in anatase TiO 2 by intentionally introducing atomic hydrogen-mediated oxygen vacancies. Combining experimental characterizations with theoretical calculations reveals the excitation of a new subvalence band associated with atomic hydrogen filled oxygen vacancies as the origin of such band, which subsequently leads to active photo-electrochemical water oxidation under visible light. These findings could provide a powerful way of tailoring wide-bandgap semiconductors to fully capture solar light. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Observation of states beyond band termination in 156,157,158Er and strongly deformed structures in 173,174,175Hf

    International Nuclear Information System (INIS)

    Riley, M A; Djongolov, M K; Evans, A O

    2006-01-01

    High-spin terminating bands in heavy nuclei were first identified in nuclei around 158 Er 90 . While examples of terminating states have been identified in a number of erbium isotopes, almost nothing is known about the states lying beyond band termination. In the present work, the high-spin structure of 156,157,158 Er has been studied using the Gammasphere spectrometer. The subject of triaxial superdeformation and 'wobbling' modes in Lu nuclei has rightly attracted a great deal of attention. Very recently four strongly or superdeformed (SD) sequences have been observed in 174 Hf, and cranking calculations using the Ultimate Cranker code predict that such structures may have significant triaxial deformation. We have performed two experiments in an attempt to verify the possible triaxial nature of these bands. A lifetime measurement was performed to confirm the large (and similar) deformation of the bands. In addition, a high-statistics, thin-target experiment took place to search for linking transitions between the SD bands, possible wobbling modes, and new SD band structures

  1. Synthesis and characterization of polyureasilazane derived SiCN ceramics

    International Nuclear Information System (INIS)

    Andronenko, Sergey I.; Stiharu, Ion; Misra, Sushil K.

    2006-01-01

    Samples of SiCN ceramics were synthesized by thermal treatment of commercially available CERASET TM polyureasilazane, used as liquid-polymer precursor, at pyrolysis temperatures of 1000, 1050, 1100, 1150, and 1200 deg. C. Electron paramagnetic resonance (EPR) signals due to sp 2 -hybridized carbon-related dangling bonds were recorded over the 4-300 K temperature range at X band (9.6 GHz), and the spectra showed the presence of an intense EPR line with g=2.0027 at room temperature for all samples; at liquid helium temperature an additional line was seen present as a shoulder to main line. These two signals are due to carbon-related dangling bonds present as (i) defects on the free-carbon phase and (ii) within the bulk of SiCN ceramic network. The value of the antiferromagnetic exchange constant between dangling bonds in the various samples, not hitherto available in the literature, was estimated from the temperature variation of the EPR linewidth to be anywhere from J=-12 to J=-15 K in the samples synthesized at 1000, 1100, and 1150 deg. C. The EPR linewidth of the samples decreased with increasing pyrolysis temperature of a sample, being 0.07 mT at X band at room temperature for the samples synthesized at 1150 and 1200 deg. C, which can be used potentially as stable g markers, due to their very narrow linewidth. The W-band (95 GHz) room-temperature spectrum of the sample pyrolyzed at 1100 deg. C exhibited only one line consistent with the X-band spectrum. At higher frequency of G band (170 GHz) the EPR spectra are better resolved, clearly showing the presence of a strong (g=2.0027) and a weak (g=2.0032) EPR line at room temperature, and the latter corresponds to the line present at X band as shoulder at liquid-helium temperature. In addition, nuclear magnetic resonance measurements were carried out to confirm the existence of free-carbon phase and oxygen atoms in the samples

  2. Evidence of significant covalent bonding in Au(CN)(2)(-).

    Science.gov (United States)

    Wang, Xue-Bin; Wang, Yi-Lei; Yang, Jie; Xing, Xiao-Peng; Li, Jun; Wang, Lai-Sheng

    2009-11-18

    The Au(CN)(2)(-) ion is the most stable Au compound known for centuries, yet a detailed understanding of its chemical bonding is still lacking. Here we report direct experimental evidence of significant covalent bonding character in the Au-C bonds in Au(CN)(2)(-) using photoelectron spectroscopy and comparisons with its lighter congeners, Ag(CN)(2)(-) and Cu(CN)(2)(-). Vibrational progressions in the Au-C stretching mode were observed for all detachment transitions for Au(CN)(2)(-), in contrast to the atomic-like transitions for Cu(CN)(2)(-), revealing the Au-C covalent bonding character. In addition, rich electronic structural information was obtained for Au(CN)(2)(-) by employing 118 nm detachment photons. Density functional theory and high-level ab initio calculations were carried out to understand the photoelectron spectra and obtain insight into the nature of the chemical bonding in the M(CN)(2)(-) complexes. Significant covalent character in the Au-C bonding due to the strong relativistic effects was revealed in Au(CN)(2)(-), consistent with its high stability.

  3. A Novel Cyanide-Bridged Thulium-Nickel Heterobimetallic Polymeric Complex (H2O)2(DMF)10Tm2[Ni(CN)4]2[Ni(CN)4] including O-H···N Hydrogen Bond

    International Nuclear Information System (INIS)

    Chung, Janghoon; Park, Daeyoung; Song, Mina; Ha, Sungin; Kang, Ansoo; Moon, Sangbong; Ryu, Cheolhwi

    2012-01-01

    The experimental section lists the observed infrared absorption frequencies for the complex. Typically bridging CN ligands have higher stretching frequencies than the terminal CN ligands. Accordingly, cyanide stretching bands (2170, 2156, 2139 cm -1 . at higher frequencies than the stretching band (2127 cm -1 ) of K 2 [Ni(CN) 4 ] are assigned to bridging cyanide ligands. The band at 2128 cm -1 is assigned to terminal cyanide ligands because their location in the cyanide stretching region compares with the absorption observed for the nonbridging cyanide ligands in K 2 [Ni(CN) 4 ]. Array (H 2 O) 2 (DMF) 10 Tm 2 [Ni(CN) 4 ] 2 [Ni(CN) 4 ] and other lanthanide metal-Ni systems display similar CN stretching patterns in their spectra. A broad absorption band at 2950-3550 cm -1 was observed in the spectrum. This supports the presence of O-H···N intermolecular hydrogen bond interactions between the polymers

  4. Chemical Complexity in Local Diffuse and Translucent Clouds: Ubiquitous Linear C3H and CH3CN, a Detection of HC3N and an Upper Limit on the Abundance of CH2CN

    Science.gov (United States)

    Liszt, Harvey; Gerin, Maryvonne; Beasley, Anthony; Pety, Jerome

    2018-04-01

    We present Jansky Very Large Array observations of 20–37 GHz absorption lines from nearby Galactic diffuse molecular gas seen against four cosmologically distant compact radio continuum sources. The main new observational results are that l-C3H and CH3CN are ubiqitous in the local diffuse molecular interstellar medium at {\\text{}}{A}{{V}} ≲ 1, while HC3N was seen only toward B0415 at {\\text{}}{A}{{V}} > 4 mag. The linear/cyclic ratio is much larger in C3H than in C3H2 and the ratio CH3CN/HCN is enhanced compared to TMC-1, although not as much as toward the Horsehead Nebula. More consequentially, this work completes a long-term program assessing the abundances of small hydrocarbons (CH, C2H, linear and cyclic C3H and C3 {{{H}}}2, and C4H and C4H‑) and the CN-bearing species (CN, HCN, HNC, HC3N, HC5N, and CH3CN): their systematics in diffuse molecular gas are presented in detail here. We also observed but did not strongly constrain the abundances of a few oxygen-bearing species, most prominently HNCO. We set limits on the column density of CH2CN, such that the anion CH2CN‑ is only viable as a carrier of diffuse interstellar bands if the N(CH2CN)/N(CH2CN‑) abundance ratio is much smaller in this species than in any others for which the anion has been observed. We argue that complex organic molecules (COMS) are not present in clouds meeting a reasonable definition of diffuse molecular gas, i.e., {\\text{}}{A}{{V}} ≲ 1 mag. Based on observations obtained with the NRAO Jansky Very Large Array (VLA).

  5. Two- and four-quasiparticle states in the interacting boson model: Strong-coupling and decoupled band patterns in the SU(3) limit

    International Nuclear Information System (INIS)

    Vretenar, D.; Paar, V.; Bonsignori, G.; Savoia, M.

    1990-01-01

    An extension of the interacting boson approximation model is proposed by allowing for two- and four-quasiparticle excitations out of the boson space. The formation of band patterns based on two- and four-quasiparticle states is investigated in the SU(3) limit of the model. For hole-type (particle-type) fermions coupled to the SU(3) prolate (oblate) core, it is shown that the algebraic K-representation basis, which is the analog of the strong-coupling basis of the geometrical model, provides an appropriate description of the low-lying two-quasiparticle bands. In the case of particle-type (hole-type) fermions coupled to the SU(3) prolate (oblate) core, a new algebraic decoupling basis is derived that is equivalent in the geometrical limit to Stephens' rotation-aligned basis. Comparing the wave functions that are obtained by diagonalization of the model Hamiltonian to the decoupling basis, several low-lying two-quasiparticle bands are identified. The effects of an interaction that conserves only the total nucleon number, mixing states with different number of fermions, are investigated in both the strong-coupling and decoupling limits. All calculations are performed for an SU(3) boson core and the h11/2 fermion orbital

  6. Strong band edge luminescence from InN films grown on Si substrates by electron cyclotron resonance-assisted molecular beam epitaxy

    International Nuclear Information System (INIS)

    Yodo, Tokuo; Yona, Hiroaki; Ando, Hironori; Nosei, Daiki; Harada, Yoshiyuki

    2002-01-01

    We observed strong band edge luminescence at 8.5-200 K from 200-880 nm thick InN films grown on 10 nm thick InN buffer layers on Si(001) and Si(111) substrates by electron cyclotron resonance-assisted molecular beam epitaxy. The InN film on the Si(001) substrate exhibited strong band edge photoluminescence (PL) emission at 1.814 eV at 8.5 K, tentatively assigned as donor to acceptor pair [DAP (α-InN)] emission from wurtzite-InN (α-InN) crystal grains, while those on Si(111) showed other stronger band edge PL emissions at 1.880, 2.081 and 2.156 eV, tentatively assigned as donor bound exciton [D 0 X(α-InN)] from α-InN grains, DAP (β-InN) and D 0 X (β-InN) emissions from zinc blende-InN (β-InN) grains, respectively

  7. Is interstellar detection of higher members of the linear radicals CnCH and CnN feasible?

    Science.gov (United States)

    Pauzat, F.; Ellinger, Y.; Mclean, A. D.

    1991-01-01

    Rotational constants and dipole moments for linear-chain radicals CnCH and CnN are estimated using a combinatiaon of ab initio molecular orbital calculations and observed data on the starting members of the series. CnCH with n = 0-5 have been observed by radioastronomy in carbon-rich interstellar clouds; higher members of the series have 2Pi ground states with large dipole moments and are strong candidates for observation. CN and C3N have also been observed by radioastronomy; higher members of the series, with the possible exception of C5N, have 2Pi ground states with near-zero dipole moments making their interstellar detection hopeless under present observational conditions. C5N can be a strong candidate only if it has a 2Sigma ground state, and best computations so far indicate that this is not the case.

  8. Is interstellar detection of higher members of the linear radicals CnCH and CnN feasible?

    International Nuclear Information System (INIS)

    Pauzat, F.; Ellinger, Y.; Mclean, A.D.

    1991-01-01

    Rotational constants and dipole moments for linear-chain radicals CnCH and CnN are estimated using a combinatiaon of ab initio molecular orbital calculations and observed data on the starting members of the series. CnCH with n = 0-5 have been observed by radioastronomy in carbon-rich interstellar clouds; higher members of the series have 2Pi ground states with large dipole moments and are strong candidates for observation. CN and C3N have also been observed by radioastronomy; higher members of the series, with the possible exception of C5N, have 2Pi ground states with near-zero dipole moments making their interstellar detection hopeless under present observational conditions. C5N can be a strong candidate only if it has a 2Sigma ground state, and best computations so far indicate that this is not the case. 20 refs

  9. Multiple stellar populations of globular clusters from homogeneous Ca-Cn photometry. II. M5 (NGC 5904) and a new filter system

    OpenAIRE

    Lee, Jae-Woo

    2017-01-01

    Using our ingeniously designed new filter systems, we investigate the multiple stellar populations of the RGB and AGB in the GC M5. Our results are the following. (1) Our cn_jwl index accurately traces the nitrogen abundances in M5, while other color indices fail to do so. (2) We find bimodal CN distributions both in the RGB and the AGB sequences, with the number ratios between the CN-weak (CN-w) and the CN-strong (CN-s) of n(CN-w):n(CN-s) = 29:71(+/- 2) and 21:79(+/- 7), respectively. (3) We...

  10. CN in the Sgr A* environment - first results

    International Nuclear Information System (INIS)

    Stankovic, M; Seaquist, E R; Muehle, S

    2006-01-01

    The radical CN, through the CN/HCN ratio, has proven to be an exceptionally good tool to study the photodissociation regions (PDRs) dominated by FUV radiation. Our region of interest, the circumnuclear disk (CND) surrounding Sgr A*, is exposed to the strong UV radiation field originating from the central stellar cluster. It contains potentially star forming cores recently elucidated by interferometric HCN observations with OVRO by Christopher et al. (2005). We present the results of preliminary observations of CN (N = 2-l) transitions with the IRAM 30-m telescope and report, for the first time, detection of CN emission in the GC region indicative of PDR, activity. This work motivates the further investigation of the role of PDRs in the clumpy medium of the Galactic center (GC) environment in global photodissociation and in promoting or inhibiting star formation in the CND

  11. A localized surface plasmon resonance (LSPR) immunosensor for CRP detection using 4-chloro-1-naphtol (4-CN) precipitation

    Science.gov (United States)

    Ha, Su-Ji; Park, Jin-Ho; Byun, Ju-Young; Ahn, Young-Deok; Kim, Min-Gon

    2017-07-01

    In this study, C-reactive protein (CRP) was detected by monitoring of LSPR shift promoted by precipitation of 4-chloro-1-naphthol (4-CN). The precipitation occurred by horseradish peroxide (HRP) catalyst which is modified at CRP-detection antibody utilized in sandwich enzyme-linked immunosorbent assay (ELISA) on gold nano bipyramid (GNBP) substrate. Due to 4-CN precipitates which are located nearby the surface of GNBP, local refractive index (RI) and molecular density were greatly increased. This phenomenon eventually induced strong spectral red-shift of absorption band of GNBP. An excellent linear relationship (R2=0.9895) between the LSPR shift and CRP concentration was obtained in the range from 100 pg/mL to 100 ng/mL and limit of detection (LOD) was reached to 87 pg/mL.

  12. Atmospheric Composition of Weak G Band Stars: CNO and Li Abundances

    Science.gov (United States)

    Adamczak, Jens; Lambert, David L.

    2013-03-01

    We determined the chemical composition of a large sample of weak G band stars—a rare class of G and K giants of intermediate mass with unusual abundances of C, N, and Li. We have observed 24 weak G band stars with the 2.7 m Harlan J. Smith Telescope at the McDonald Observatory and derived spectroscopic abundances for C, N, O, and Li, as well as for selected elements from Na-Eu. The results show that the atmospheres of weak G band stars are highly contaminated with CN-cycle products. The C underabundance is about a factor of 20 larger than for normal giants and the 12C/13C ratio approaches the CN-cycle equilibrium value. In addition to the striking CN-cycle signature the strong N overabundance may indicate the presence of partially ON-cycled material in the atmospheres of the weak G band stars. The exact mechanism responsible for the transport of the elements to the surface has yet to be identified but could be induced by rapid rotation of the main sequence progenitors of the stars. The unusually high Li abundances in some of the stars are an indicator for Li production by the Cameron-Fowler mechanism. A quantitative prediction of a weak G band star's Li abundance is complicated by the strong temperature sensitivity of the mechanism and its participants. In addition to the unusual abundances of CN-cycle elements and Li, we find an overabundance of Na that is in accordance with the NeNa chain running in parallel with the CN cycle. Apart from these peculiarities, the element abundances in a weak G band star's atmosphere are consistent with those of normal giants.

  13. ATMOSPHERIC COMPOSITION OF WEAK G BAND STARS: CNO AND Li ABUNDANCES

    International Nuclear Information System (INIS)

    Adamczak, Jens; Lambert, David L.

    2013-01-01

    We determined the chemical composition of a large sample of weak G band stars—a rare class of G and K giants of intermediate mass with unusual abundances of C, N, and Li. We have observed 24 weak G band stars with the 2.7 m Harlan J. Smith Telescope at the McDonald Observatory and derived spectroscopic abundances for C, N, O, and Li, as well as for selected elements from Na-Eu. The results show that the atmospheres of weak G band stars are highly contaminated with CN-cycle products. The C underabundance is about a factor of 20 larger than for normal giants and the 12 C/ 13 C ratio approaches the CN-cycle equilibrium value. In addition to the striking CN-cycle signature the strong N overabundance may indicate the presence of partially ON-cycled material in the atmospheres of the weak G band stars. The exact mechanism responsible for the transport of the elements to the surface has yet to be identified but could be induced by rapid rotation of the main sequence progenitors of the stars. The unusually high Li abundances in some of the stars are an indicator for Li production by the Cameron-Fowler mechanism. A quantitative prediction of a weak G band star's Li abundance is complicated by the strong temperature sensitivity of the mechanism and its participants. In addition to the unusual abundances of CN-cycle elements and Li, we find an overabundance of Na that is in accordance with the NeNa chain running in parallel with the CN cycle. Apart from these peculiarities, the element abundances in a weak G band star's atmosphere are consistent with those of normal giants.

  14. CN and HCN in the infrared spectrum of IRC + 10216

    Science.gov (United States)

    Wiedemann, G. R.; Deming, D.; Jennings, D. E.; Hinkle, Kenneth H.; Keady, John J.

    1991-01-01

    The abundance of HCN in the inner circumstellar shell of IRC + 10216 has been remeasured using the 12-micron nu2 band. The 12-micron lines are less saturated than HCN 3-micron lines previously detected in the spectrum of IRC + 10216. The observed 12-micron HCN line is formed in the circumstellar shell from about 4 to 12 R sub * in accord with a photospheric origin for HCN. The derived HCN abundance in the 4 to 12 R sub* region is 4 x 10 exp-5 and the column density is 7 x 10 exp 18/sq cm. The 5-micron CN vibration-rotation fundamental band was detected for the first time in an astronomical source. Using four CN lines, the CN column density was determined to be 2.6 x 10 exp 15/sq cm and the rotational temperature to be 8 +/-2 K. The peal radial abundance is 1 x 10 exp -5. The values for the temperature and abundance are in good agreement with microwave results and with the formation of CN from the photolysis of HCN.

  15. CN radical in diffuse interstellar clouds

    International Nuclear Information System (INIS)

    Federman, S.R.; Danks, A.C.; Lambert, D.L.

    1984-01-01

    A survey of 15 lines of sight for the CN B 2 Σ + --X 2 Σ + interstellar absorption lines shows that the CN column density in diffuse interstellar clouds follows the relation log N(CN)proportionalm log N(H 2 ), where mroughly-equal3. This result is reproduced by a reaction network in which CN is produced primarily from C 2 by the neutral-neutral reaction C 2 +N → CN+C, and photodissociation is the main destruction pathway for the neutral molecules CH, C 2 , and CN. The CN radical is the first molecular species observed in diffuse clouds that requires a neutral-neutral reaction for its formation in the gas phase. The network also reproduces the observed ratio N(CN)/N(H 2 )

  16. Raman study of vibrational dephasing in liquid CH3CN and CD3CN

    International Nuclear Information System (INIS)

    Schroeder, J.; Schiemann, V.H.; Sharko, P.T.; Jonas, J.

    1977-01-01

    The Raman line shapes of the ν 1 (a 1 ) C--H and C--D fundamentals in liquid acetonitrile and acetonitrile-d 3 have been measured as a function of pressure up to 4 kbar within the temperature interval 30--120 degreeC. Densities have also been determined. From the isotropic component of the vibrational Raman band shape the vibrational relaxation times have been obtained as a function of temperature and pressure (density). The experimental results can be summarized as follows: (i) as T increases at constant density rho, the vibrational relaxation rate (tau/sub vib/) -1 increases; (ii) at constant T as density is raised tau/sub vib/ -1 increases; (iii) at constant pressure the T increase produces higher tau/sub vib/ -1 , however, the change is more pronounced for the CD 3 CN liquid. Isotopic dilution studies of the CH 3 CN/CD 3 CN mixtures shows no significant effect on (tau/sub vib/ -1 ). The experimental data are interpreted in terms of the Kubo stochastic line shape theory and the dephasing model of Fischer and Laubereau. The results based on Kubo formalism indicate that dephasing is the dominant relaxation mechanism and that the modulation is fast. The isolated binary collision model proposed by Fischer and Laubereau for vibrational dephasing reproduces the essential features of the density and temperature dependence of the (tau/sub vib/) -1 and suggests that pure dephasing is the dominant broadening mechanism for the isotropic line shapes studied. In the calculation the elastic collision times were approximated by the Enskog relaxation times

  17. Experimental study and calculations of nitric oxide absorption in the γ(0,0) and γ(1,0) bands for strong temperature conditions

    International Nuclear Information System (INIS)

    Trad, H.; Higelin, P.; Djebaieli-Chaumeix, N.; Mounaim-Rousselle, C.

    2005-01-01

    Absorption spectra of nitric oxide in the γ(0,0) and γ(1,0) bands have been measured for hard temperature conditions up to 1700 K in order to validate a model for the simulation of these two bands. The good agreement between experiments and calculations (relative errors of 2-5% for the γ(0,0) band and 10-15% for the γ(1,0) band) consolidates the two important assumptions concerning the intermediate Hund's case between (a) and (b) for the X 2 Π state of the γ(0,0) and γ(1,0) absorption bands and the use of collisional broadening parameters of γ(0,0) to simulate the γ(1,0) band. Using this simulation, a study of the Beer-Lambert law behavior at high temperature has been carried out. With the instrument resolution used for these experiments, it was shown that a correction of the Beer-Lambert law is necessary. To apply this technique for the measurements of NO concentrations inside the combustion chamber of an optical SI engine, a new formulation of the Beer-Lambert law has been introduced, since the modified form proposed in the literature is no longer applicable in the total column range of interest

  18. Cubic mesoporous Ag@CN: a high performance humidity sensor.

    Science.gov (United States)

    Tomer, Vijay K; Thangaraj, Nishanthi; Gahlot, Sweta; Kailasam, Kamalakannan

    2016-12-01

    The fabrication of highly responsive, rapid response/recovery and durable relative humidity (%RH) sensors that can precisely monitor humidity levels still remains a considerable challenge for realizing the next generation humidity sensing applications. Herein, we report a remarkably sensitive and rapid %RH sensor having a reversible response using a nanocasting route for synthesizing mesoporous g-CN (commonly known as g-C 3 N 4 ). The 3D replicated cubic mesostructure provides a high surface area thereby increasing the adsorption, transmission of charge carriers and desorption of water molecules across the sensor surfaces. Owing to its unique structure, the mesoporous g-CN functionalized with well dispersed catalytic Ag nanoparticles exhibits excellent sensitivity in the 11-98% RH range while retaining high stability, negligible hysteresis and superior real time %RH detection performances. Compared to conventional resistive sensors based on metal oxides, a rapid response time (3 s) and recovery time (1.4 s) were observed in the 11-98% RH range. Such impressive features originate from the planar morphology of g-CN as well as unique physical affinity and favourable electronic band positions of this material that facilitate water adsorption and charge transportation. Mesoporous g-CN with Ag nanoparticles is demonstrated to provide an effective strategy in designing high performance %RH sensors and show great promise for utilization of mesoporous 2D layered materials in the Internet of Things and next generation humidity sensing applications.

  19. ESR studies on the spin-liquid candidate κ-(BEDT-TTF)2Cu2(CN)3: Anomalous response below T=8 K

    International Nuclear Information System (INIS)

    Padmalekha, K.G.; Blankenhorn, M.; Ivek, T.; Bogani, L.; Schlueter, J.A.; Dressel, M.

    2015-01-01

    The organic conductor κ-(BEDT-TTF) 2 Cu 2 (CN) 3 seems to form a quantum spin liquid, although at low temperatures unusual properties are seen in the charge, spin and lattice degrees of freedom. Here we report results of X-band ESR studies of κ-(BEDT-TTF) 2 Cu 2 (CN) 3 single crystals as a function of temperature and angle. We find indications of two anisotropic relaxation mechanisms at low temperatures and compare them to the spin-liquid behavior observed in other strongly correlated systems. In addition, we can recognize charge inhomogeneities in the copper ions of the anion layer. This disorder might be linked to the dielectric response measured in this compound

  20. ESR studies on the spin-liquid candidate κ-(BEDT-TTF){sub 2}Cu{sub 2}(CN){sub 3}: Anomalous response below T=8 K

    Energy Technology Data Exchange (ETDEWEB)

    Padmalekha, K.G.; Blankenhorn, M.; Ivek, T.; Bogani, L. [1. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart (Germany); Schlueter, J.A. [Materials Science Division, Argonne National Laboratory, Argonne, IL 60439 (United States); Dressel, M., E-mail: dressel@pi1.physik.uni-stuttgart.de [1. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, D-70550 Stuttgart (Germany)

    2015-03-01

    The organic conductor κ-(BEDT-TTF){sub 2}Cu{sub 2}(CN){sub 3} seems to form a quantum spin liquid, although at low temperatures unusual properties are seen in the charge, spin and lattice degrees of freedom. Here we report results of X-band ESR studies of κ-(BEDT-TTF){sub 2}Cu{sub 2}(CN){sub 3} single crystals as a function of temperature and angle. We find indications of two anisotropic relaxation mechanisms at low temperatures and compare them to the spin-liquid behavior observed in other strongly correlated systems. In addition, we can recognize charge inhomogeneities in the copper ions of the anion layer. This disorder might be linked to the dielectric response measured in this compound.

  1. ESR studies on the spin-liquid candidate κ-(BEDT-TTF)2Cu2(CN)3: Anomalous response below T=8 K

    Science.gov (United States)

    Padmalekha, K. G.; Blankenhorn, M.; Ivek, T.; Bogani, L.; Schlueter, J. A.; Dressel, M.

    2015-03-01

    The organic conductor κ-(BEDT-TTF)2Cu2(CN)3 seems to form a quantum spin liquid, although at low temperatures unusual properties are seen in the charge, spin and lattice degrees of freedom. Here we report results of X-band ESR studies of κ-(BEDT-TTF)2Cu2(CN)3 single crystals as a function of temperature and angle. We find indications of two anisotropic relaxation mechanisms at low temperatures and compare them to the spin-liquid behavior observed in other strongly correlated systems. In addition, we can recognize charge inhomogeneities in the copper ions of the anion layer. This disorder might be linked to the dielectric response measured in this compound.

  2. Estimation of CN Parameter for Small Agricultural Watersheds Using Asymptotic Functions

    Directory of Open Access Journals (Sweden)

    Tomasz Kowalik

    2015-03-01

    Full Text Available This paper investigates a possibility of using asymptotic functions to determine the value of curve number (CN parameter as a function of rainfall in small agricultural watersheds. It also compares the actually calculated CN with its values provided in the Soil Conservation Service (SCS National Engineering Handbook Section 4: Hydrology (NEH-4 and Technical Release 20 (TR-20. The analysis showed that empirical CN values presented in the National Engineering Handbook tables differed from the actually observed values. Calculations revealed a strong correlation between the observed CN and precipitation (P. In three of the analyzed watersheds, a typical pattern of the observed CN stabilization during abundant precipitation was perceived. It was found that Model 2, based on a kinetics equation, most effectively described the P-CN relationship. In most cases, the observed CN in the investigated watersheds was similar to the empirical CN, corresponding to average moisture conditions set out by NEH-4. Model 2 also provided the greatest stability of CN at 90% sampled event rainfall.

  3. Anomalous absorption in H2CN and CH2CN molecules

    Indian Academy of Sciences (India)

    Abstract. Structures of H2CN and CH2CN molecules are similar to that of H2CO mole- cule. The H2CO has shown anomalous absorption for its transition 111 − 110 at 4.8 GHz in a number of cool molecular clouds. Though the molecules H2CN and CH2CN have been identified in TMC-1 and Sgr B2 through some ...

  4. Cyanide-limited complexation of molybdenum(III): synthesis of octahedral [Mo(CN)(6)](3-) and cyano-bridged [Mo(2)(CN)(11)](5-).

    Science.gov (United States)

    Beauvais, Laurance G; Long, Jeffrey R

    2002-03-13

    Octahedral coordination of molybdenum(III) is achieved by limiting the amount of cyanide available upon complex formation. Reaction of Mo(CF(3)SO(3))(3) with LiCN in DMF affords Li(3)[Mo(CN)(6)] x 6DMF (1), featuring the previously unknown octahedral complex [Mo(CN)(6)](3-). The complex exhibits a room-temperature moment of mu(eff) = 3.80 mu(B), and assignment of its absorption bands leads to the ligand field parameters Delta(o) = 24800 cm(-1) and B = 247 cm(-1). Further restricting the available cyanide in a reaction between Mo(CF(3)SO(3))(3) and (Et(4)N)CN in DMF, followed by recrystallization from DMF/MeOH, yields (Et(4)N)(5)[Mo(2)(CN)(11)] x 2DMF x 2MeOH (2). The dinuclear [Mo(2)(CN)(11)](5-) complex featured therein contains two octahedrally coordinated Mo(III) centers spanned by a bridging cyanide ligand. A fit to the magnetic susceptibility data for 2, gives J = -113 cm(-1) and g = 2.33, representing the strongest antiferromagnetic coupling yet observed through a cyanide bridge. Efforts to incorporate these new complexes in magnetic Prussian blue-type solids are ongoing.

  5. The Exciton-Polariton Dispersion Law under the Action of Strong Pumping in the Region of the M-Band of Luminescence

    Science.gov (United States)

    Khadzhi, P. I.; Nad'kin, L. Yu.; Markov, D. A.

    2018-04-01

    The double-pulse interaction with excitons and biexcitons in semiconductors is studied theoretically. It is shown that the dispersion law of carrier wave has three branches under the action of a powerful pumping in the region of the M-band of luminescence. Values of parameters at which the dispersion law branches can intersect due to the degeneration of the exciton level energy have been found. The effect of a significant change in the force of coupling between the exciton and photon of a weak pulse with a change in the pumping intensity is predicted.

  6. Infrared and dc conductivity in metals with strong scattering: Nonclassical behavior from a generalized Boltzmann equation containing band-mixing effects

    International Nuclear Information System (INIS)

    Allen, P.B.; Chakraborty, B.

    1981-01-01

    Metals with high resistivity (approx.100 μΩ cm) seem to show weaker variation of resistivity (as a function of temperature and perhaps also static disorder) than predicted by semiclassical (Bloch-Boltzmann) theory (SBT). We argue that the effect is not closely related to Anderson localization, and therefore does not necessarily signify a failure of the independent collision approximation. Instead we propose a failure of the semiclassical acceleration and conduction approximations. A generalization of Boltzmann theory is made which includes quantum (interband) acceleration and conduction, as well as a complete treatment of interband-collision effects (within the independent-collision approximation). The interband terms enhance short-time response to E fields (because the theory satisfies the exact f-sum rule instead of the semiclassical approximation to it). This suggests that the additional conductivity, as expressed phenomenologically by the shunt resistor model, is explained by interband effects. The scattering operator is complex, its imaginary parts being related to energy-band renormalization caused by the disorder. Charge conservation is respected and thermal equilibrium is restored by the collision operator. The theory is formally solved for the leading corrections to SBT, which have the form of a shunt resistor model. At infrared frequencies, the conductivity mostly obeys the Drude law sigma(ω)approx.sigma(0)(1-iωtau) -1 , except for one term which goes as (1-iωtau) -2

  7. Clues to NaCN formation

    Science.gov (United States)

    Quintana-Lacaci, G.; Cernicharo, J.; Velilla Prieto, L.; Agúndez, M.; Castro-Carrizo, A.; Fonfría, J. P.; Massalkhi, S.; Pardo, J. R.

    2017-11-01

    Context. ALMA is providing us essential information on where certain molecules form. Observing where these molecules emission arises from, the physical conditions of the gas, and how this relates with the presence of other species allows us to understand the formation of many species, and to significantly improve our knowledge of the chemistry that occurs in the space. Aims: We studied the molecular distribution of NaCN around IRC +10216, a molecule detected previously, but whose origin is not clear. High angular resolution maps allow us to model the abundance distribution of this molecule and check suggested formation paths. Methods: We modeled the emission of NaCN assuming local thermal equilibrium (LTE) conditions. These profiles were fitted to azimuthal averaged intensity profiles to obtain an abundance distribution of NaCN. Results: We found that the presence of NaCN seems compatible with the presence of CN, probably as a result of the photodissociation of HCN, in the inner layers of the ejecta of IRC +10216. However, similar as for CH3CN, current photochemical models fail to reproduce this CN reservoir. We also found that the abundance peak of NaCN appears at a radius of 3 × 1015 cm, approximately where the abundance of NaCl, suggested to be the parent species, starts to decay. However, the abundance ratio shows that the NaCl abundance is lower than that obtained for NaCN. We expect that the LTE assumption might result in NaCN abundances higher than the real ones. Updated photochemical models, collisional rates, and reaction rates are essential to determine the possible paths of the NaCN formation. Based on observations carried out with ALMA and the IRAM 30 m Telescope. ALMA is a partnership of ESO (representing its member states), NSF (USA) and NINS (Japan), together with NRC (Canada) and NSC and ASIAA (Taiwan), in cooperation with the Republic of Chile. The Joint ALMA Observatory is operated by ESO, AUI/NRAO and NAOJ. IRAM is supported by INSU/CNRS (France

  8. Polarization due to dust scattering in the planetary nebula Cn1-1

    International Nuclear Information System (INIS)

    Bhatt, H.C.

    1989-01-01

    The peculiar emission-line object Cn1-1 (=HDE330036=PK330+4 degrees 1), classified both as a symbiotic star and as a planetary nebula, was detected by the Infrared Astronomical Satellite (IRAS) as a strong source of far-infrared dust in the system. Bhatt and Mallik (1986) discussed the nature of the dust in Cn1-1 and argued that the object is a Type I protoplanetary nebula in a binary system. The argument presented here is that the polarization is intrinsic to Cn1-1 and is due to scattering by large (compared to interstellar) dust grains in the protoplanetary nebula that are asymmetrically distributed around the central star. The large degree of polarization (approximately 3 percent for the Cn1-1 distance of approximately 450 pc) with a large lambda(sub max) is naturally explained if it is caused by scattering by large dust grains in the Cn1-1 nebula. Since the H(sub alpha) line is also polarized at the same level and position angle as the continuum, the dust must be asymmetrically distributed around the central star. The morphology of the protoplanetary nebula in Cn1-1 may be bipolar. Thus, the polarization observations support the suggestion that Cn1-1 is a bipolar Type I planetary nebula

  9. Multiple Stellar Populations of Globular Clusters from Homogeneous Ca-CN Photometry. II. M5 (NGC 5904) and a New Filter System

    Science.gov (United States)

    Lee, Jae-Woo

    2017-07-01

    Using our ingeniously designed new filter systems, we investigate multiple stellar populations of the red giant branch (RGB) and the asymptotic giant branch (AGB) in the globular cluster (GC) M5. Our results are the following. (1) Our {{cn}}{JWL} index accurately traces nitrogen abundances in M5, while other color indices fail to do so. (2) We find bimodal CN distributions in both RGB and AGB sequences, with number ratios between CN-weak (CN-w) and CN-strong (CN-s) of n(CN-w):n(CN-s) = 29:71 (±2) and 21:79 (±7), respectively. (3) We also find a bimodal photometric [N/Fe] distribution for M5 RGB stars. (4) Our {{cn}}{JWL}-[O/Fe] and {{cn}}{JWL}-[Na/Fe] relations show clear discontinuities between the two RGB populations. (5) Although small, the RGB bump of CN-s is slightly brighter, {{Δ }}{V}{bump} = 0.07 ± 0.04 mag. If real, the difference in the helium abundance becomes {{Δ }}Y = 0.028 ± 0.016, in the sense that CN-s is more helium enhanced. (6) Very similar radial but different spatial distributions with comparable center positions are found for the two RGB populations. The CN-s RGB and AGB stars are more elongated along the NW-SE direction. (7) The CN-s population shows a substantial net projected rotation, while that of the CN-w population is nil. (8) Our results confirm the deficiency of CN-w AGB stars previously noted by others. We show that it is most likely due to stochastic truncation in the outer part of the cluster. Finally, we discuss the formation scenario of M5. Based on observations made with the Cerro Tololo Inter-American Observatory (CTIO) 1 m telescope, which is operated by the SMARTS consortium.

  10. CN rings in full protoplanetary disks around young stars as probes of disk structure

    Science.gov (United States)

    Cazzoletti, P.; van Dishoeck, E. F.; Visser, R.; Facchini, S.; Bruderer, S.

    2018-01-01

    Aims: Bright ring-like structure emission of the CN molecule has been observed in protoplanetary disks. We investigate whether such structures are due to the morphology of the disk itself or if they are instead an intrinsic feature of CN emission. With the intention of using CN as a diagnostic, we also address to which physical and chemical parameters CN is most sensitive. Methods: A set of disk models were run for different stellar spectra, masses, and physical structures via the 2D thermochemical code DALI. An updated chemical network that accounts for the most relevant CN reactions was adopted. Results: Ring-shaped emission is found to be a common feature of all adopted models; the highest abundance is found in the upper outer regions of the disk, and the column density peaks at 30-100 AU for T Tauri stars with standard accretion rates. Higher mass disks generally show brighter CN. Higher UV fields, such as those appropriate for T Tauri stars with high accretion rates or for Herbig Ae stars or for higher disk flaring, generally result in brighter and larger rings. These trends are due to the main formation paths of CN, which all start with vibrationally excited H_2^* molecules, that are produced through far ultraviolet (FUV) pumping of H2. The model results compare well with observed disk-integrated CN fluxes and the observed location of the CN ring for the TW Hya disk. Conclusions: CN rings are produced naturally in protoplanetary disks and do not require a specific underlying disk structure such as a dust cavity or gap. The strong link between FUV flux and CN emission can provide critical information regarding the vertical structure of the disk and the distribution of dust grains which affects the UV penetration, and could help to break some degeneracies in the SED fitting. In contrast with C2H or c-C3H2, the CN flux is not very sensitive to carbon and oxygen depletion.

  11. Phonon dispersion curves for CsCN

    International Nuclear Information System (INIS)

    Gaur, N.K.; Singh, Preeti; Rini, E.G.; Galgale, Jyostna; Singh, R.K.

    2004-01-01

    The motivation for the present work was gained from the recent publication on phonon dispersion curves (PDCs) of CsCN from the neutron scattering technique. We have applied the extended three-body force shell model (ETSM) by incorporating the effect of coupling between the translation modes and the orientation of cyanide molecules for the description of phonon dispersion curves of CsCN between the temperatures 195 and 295 K. Our results on PDCs in symmetric direction are in good agreement with the experimental data measured with inelastic neutron scattering technique. (author)

  12. Solid solution cermet: (Ti,Nb)(CN)-Ni cermet.

    Science.gov (United States)

    Kwon, Hanjung; Jung, Sun-A

    2014-11-01

    Solid solution powders without W, (Ti,Nb)(CN) powders with a B1 structure (NaCl like), were synthesized by high energy milling and carbothermal reduction in nitrogen. The range of molar ratios of Ti/Nb for forming complete (Ti,Nb)(CN) phase was broader than that of Ti/W for the (Ti,W)(CN) phase because carbide or carbonitride of Nb had a B1 crystal structure identical to Ti(CN) while WC had a hexagonal crystal structure. The results revealed that the hardness of (Ti,Nb)(CN)-Ni cermets was higher than that of (Ti,W)(CN)-Ni cermets. The lower density of the (Ti,Nb)(CN) powder contributed to the higher hardness compared to (Ti,W)(CN) because the volumetric ratio of (Ti,Nb)(CN) in the (Ti,Nb)(CN)-Ni cermets was higher than that of (Ti,Nb)(CN) in the (Ti,W)(CN)-Ni cermets at the same weight ratio of Ni. Additionally, it was assumed that intrinsic the properties of (Ti,Nb)(CN) could also be the cause for the high hardness of the (Ti,Nb)(CN)-Ni cermets.

  13. CN molecule vibrational spectra excitation in several LTE plasma sources conditions

    International Nuclear Information System (INIS)

    Iova, I.; Iova, Floriana; Ionita, I.; Bazavan, M.; Ilie, Gh.; Stanescu, G.

    2001-01-01

    Our interest in CN plasma study steams of the facilities to obtain the CN radicals in a free atmosphere electric discharge where the C of the coal electrodes can to combine in the enough high temperature plasma with the atmospheric nitrogen. Also of much interest is the very important phenomena in which the CN vibrational spectra can be implied and used as a diagnostic tool (plasma chemistry, astrophysics and so on). A peculiar importance presents the CN vibrational spectra in the transient plasmas. It is the reason why we have investigated here some internal processes of a continued and interrupted arc of various pulse lengths. To these purposes we present with enough accuracy the behaviour of the relative band head intensities of the sequences Δ v = +1 and Δ v = 0 belonging to the CN electronic transition (B 2 Σ - X 2 Σ), as a function of the pulse length (50 - 200 ms) as well as a function of the cathode to anode separation. These behaviours give us indications on the vibrational levels of the electronic state populations in several regions of the arc plasma as well on the efficiency of these levels excitation for several plasma pulse lengths. (authors)

  14. New solar carbon abundance based on non-LTE CN molecular spectra

    International Nuclear Information System (INIS)

    Mount, G.H.; Linsky, J.L.

    1975-01-01

    A detailed non-LTE analysis of solar CN spectra strongly suggests a revised carbon abundance for the Sun. A value of log A/subc/=8.35plus-or-minus0.15 which is significantly lower than the presently accepted value of log A/subc/=8.55 is suggested. This revision may have important consequences in astrophysics

  15. H12CN and H13CN excitation analysis in the circumstellar outflow of R Sculptoris

    Science.gov (United States)

    Saberi, M.; Maercker, M.; De Beck, E.; Vlemmings, W. H. T.; Olofsson, H.; Danilovich, T.

    2017-03-01

    Context. The 12CO/13CO isotopologue ratio in the circumstellar envelope (CSE) of asymptotic giant branch (AGB) stars has been extensively used as the tracer of the photospheric 12C/13C ratio. However, spatially-resolved ALMA observations of R Scl, a carbon rich AGB star, have shown that the 12CO/13CO ratio is not consistent over the entire CSE. Hence, it can not necessarily be used as a tracer of the 12C/13C ratio. The most likely hypothesis to explain the observed discrepancy between the 12CO/13CO and 12C/13C ratios is CO isotopologue selective photodissociation by UV radiation. Unlike the CO isotopologue ratio, the HCN isotopologue ratio is not affected by UV radiation. Therefore, HCN isotopologue ratios can be used as the tracer of the atomic C ratio in UV irradiated regions. Aims: We aim to present ALMA observations of H13CN(4-3) and APEX observations of H12CN(2-1), H13CN(2-1, 3-2) towards R Scl. These new data, combined with previously published observations, are used to determine abundances, ratio, and the sizes of line-emitting regions of the aforementioned HCN isotopologues. Methods: We have performed a detailed non-LTE excitation analysis of circumstellar H12CN(J = 1-0, 2-1, 3-2, 4-3) and H13CN(J = 2-1, 3-2, 4-3) line emission around R Scl using a radiative transfer code based on the accelerated lambda iteration (ALI) method. The spatial extent of the molecular distribution for both isotopologues is constrained based on the spatially resolved H13CN(4-3) ALMA observations. Results: We find fractional abundances of H12CN/H2 = (5.0 ± 2.0) × 10-5 and H13CN/H2 = (1.9 ± 0.4) × 10-6 in the inner wind (r ≤ (2.0 ± 0.25) ×1015 cm) of R Scl. The derived circumstellar isotopologue ratio of H12CN/H13CN = 26.3 ± 11.9 is consistent with the photospheric ratio of 12C/13C 19 ± 6. Conclusions: We show that the circumstellar H12CN/H13CN ratio traces the photospheric 12C/13C ratio. Hence, contrary to the 12CO/13CO ratio, the H12CN/H13CN ratio is not affected by UV

  16. SCS-CN parameter determination using rainfall-runoff data in heterogeneous watersheds. The two-CN system approach

    OpenAIRE

    K. X. Soulis; J. D. Valiantzas

    2011-01-01

    The Soil Conservation Service Curve Number (SCS-CN) approach is widely used as a simple method for predicting direct runoff volume for a given rainfall event. The CN values can be estimated by being selected from tables. However, it is more accurate to estimate the CN value from measured rainfall-runoff data (assumed available) in a watershed. Previous researchers indicated that the CN values calculated from measured rainfall-runoff data vary systematically with the rainfall depth. The...

  17. Phonons and colossal thermal expansion behavior of Ag3Co(CN)6 and Ag3Fe(CN)6.

    Science.gov (United States)

    Mittal, R; Zbiri, M; Schober, H; Achary, S N; Tyagi, A K; Chaplot, S L

    2012-12-19

    Recently colossal volume thermal expansion has been observed in the framework compounds Ag(3)Co(CN)(6) and Ag(3)Fe(CN)(6). We have measured phonon spectra using neutron time-of-flight spectroscopy as a function of temperature and pressure. Ab initio calculations were carried out for the sake of analysis and interpretation. Bonding is found to be very similar in the two compounds. At ambient pressure, modes in the intermediate frequency part of the vibrational spectra in the Co compound are shifted slightly to higher energies as compared to the Fe compound. The temperature dependence of the phonon spectra gives evidence for a large explicit anharmonic contribution to the total anharmonicity for low-energy modes below 5 meV. We have found that modes are mainly affected by the change in size of the unit cell, which in turn changes the bond lengths and vibrational frequencies. Thermal expansion has been calculated via the volume dependence of phonon spectra. Our analysis indicates that Ag phonon modes within the energy range 2-5 meV are strongly anharmonic and major contributors to thermal expansion in both systems. The application of pressure hardens the low-energy part of the phonon spectra involving Ag vibrations and confirms the highly anharmonic nature of these modes.

  18. Structural phase transitions in Zn(CN)2 under high pressures

    International Nuclear Information System (INIS)

    Poswal, H.K.; Tyagi, A.K.; Lausi, Andrea; Deb, S.K.; Sharma, Surinder M.

    2009-01-01

    High pressure behavior of zinc cyanide (Zn(CN) 2 ) has been investigated with the help of synchrotron-based X-ray diffraction measurements. Our studies reveal that under pressure this compound undergoes phase transformations and the structures of the new phases depend on whether the pressure is hydrostatic or not. Under hydrostatic conditions, Zn(CN) 2 transforms from cubic to orthorhombic to cubic-II to amorphous phases. In contrast, the non-hydrostatic pressure conditions drive the ambient cubic phase to a partially disordered crystalline phase, which eventually evolves to a substantially disordered phase. The final disordered phase in the latter case is distinct from the amorphous phase observed under the hydrostatic pressures. - Graphical abstract: High pressure X-ray diffraction investigations on Zn(CN) 2 show three phase transformations i.e., cubic→orthorhombic→cubic-II→amorphous. However, the results strongly depend upon the nature of stress

  19. Light fragment preformation in cold fission of {sup 282}Cn

    Energy Technology Data Exchange (ETDEWEB)

    Poenaru, D.N.; Gherghescu, R.A. [Horia Hulubei National Institute of Physics and Nuclear Engineering (IFIN-HH), P.O. Box MG-6, Bucharest-Magurele (Romania); Johann Wolfgang Goethe University, Frankfurt Institute for Advanced Studies (FIAS), Frankfurt am Main (Germany)

    2016-11-15

    In a previous article, published in Phys. Rev. C 94, 014309 (2016), we have shown for the first time that the best dynamical trajectory during the deformation toward fission of the superheavy nucleus {sup 286}Fl is a linearly increasing radius of the light fragment, R{sub 2}. This macroscopic-microscopic result reminds us about the α or cluster preformation at the nuclear surface, assumed already in 1928, and proved microscopically many times. This time we give more detailed arguments for the nucleus {sup 282}Cn. Also similar figures are presented for heavy nuclei {sup 240}Pu and {sup 252} Cf. The deep minimum of the total deformation energy near the surface is shown for the first time as a strong argument for cluster preformation. (orig.)

  20. Uniaxial strain effects on transport properties of a supramolecular organic conductor theta-(DIETS) sub 2 [Au(CN) sub 4

    CERN Document Server

    Tajima, N; Kato, R; Nishio, Y; Kajita, K

    2003-01-01

    Pressure-controlled switching between an insulating state and a superconducting state has been successfully realized on a supramolecular organic conductor theta-(DIETS) sub 2 [Au(CN) sub 4] [DIETS = diiodo(ethylenedithio)diselenadithiafulvalene]. Strong contact between iodine on the donor (DIETS) molecule and nitrogen on the anion [Au(CN) sub 4] genetates characteristic uniaxial strain effects on transport properties. Under the ambient pressure, the present system undergoes a semiconductor-insulator transition at 226 K. The effect of strains parallel to the conduction plane (ab-plane) is very small. Even under uniaxial strains up to 20 kbar along the a- and b-axis directions, the transition is not suppressed. Surprisingly, however, the c-axis strain induces a superconducting state with T sub c of 8.6 K at 10 kbar. Band parameter calculation and the conductivity anisotropy ratio suggest that an increase in the bandwidth W associated with a c-axis strain transforms the system to the metallic and superconducting...

  1. SCS-CN parameter determination using rainfall-runoff data in heterogeneous watersheds. The two-CN system approach

    Science.gov (United States)

    Soulis, K. X.; Valiantzas, J. D.

    2011-10-01

    The Soil Conservation Service Curve Number (SCS-CN) approach is widely used as a simple method for predicting direct runoff volume for a given rainfall event. The CN values can be estimated by being selected from tables. However, it is more accurate to estimate the CN value from measured rainfall-runoff data (assumed available) in a watershed. Previous researchers indicated that the CN values calculated from measured rainfall-runoff data vary systematically with the rainfall depth. They suggested the determination of a single asymptotic CN value observed for very high rainfall depths to characterize the watersheds' runoff response. In this paper, the novel hypothesis that the observed correlation between the calculated CN value and the rainfall depth in a watershed reflects the effect of the inevitable presence of soil-cover complex spatial variability along watersheds is being tested. Based on this hypothesis, the simplified concept of a two-CN heterogeneous system is introduced to model the observed CN-rainfall variation by reducing the CN spatial variability into two classes. The behavior of the CN-rainfall function produced by the proposed two-CN system concept is approached theoretically, it is analyzed systematically, and it is found to be similar to the variation observed in natural watersheds. Synthetic data tests, natural watersheds examples, and detailed study of two natural experimental watersheds with known spatial heterogeneity characteristics were used to evaluate the method. The results indicate that the determination of CN values from rainfall runoff data using the proposed two-CN system approach provides reasonable accuracy and it over performs the previous original method based on the determination of a single asymptotic CN value. Although the suggested method increases the number of unknown parameters to three (instead of one), a clear physical reasoning for them is presented.

  2. SCS-CN parameter determination using rainfall-runoff data in heterogeneous watersheds - the two-CN system approach

    Science.gov (United States)

    Soulis, K. X.; Valiantzas, J. D.

    2012-03-01

    The Soil Conservation Service Curve Number (SCS-CN) approach is widely used as a simple method for predicting direct runoff volume for a given rainfall event. The CN parameter values corresponding to various soil, land cover, and land management conditions can be selected from tables, but it is preferable to estimate the CN value from measured rainfall-runoff data if available. However, previous researchers indicated that the CN values calculated from measured rainfall-runoff data vary systematically with the rainfall depth. Hence, they suggested the determination of a single asymptotic CN value observed for very high rainfall depths to characterize the watersheds' runoff response. In this paper, the hypothesis that the observed correlation between the calculated CN value and the rainfall depth in a watershed reflects the effect of soils and land cover spatial variability on its hydrologic response is being tested. Based on this hypothesis, the simplified concept of a two-CN heterogeneous system is introduced to model the observed CN-rainfall variation by reducing the CN spatial variability into two classes. The behaviour of the CN-rainfall function produced by the simplified two-CN system is approached theoretically, it is analysed systematically, and it is found to be similar to the variation observed in natural watersheds. Synthetic data tests, natural watersheds examples, and detailed study of two natural experimental watersheds with known spatial heterogeneity characteristics were used to evaluate the method. The results indicate that the determination of CN values from rainfall runoff data using the proposed two-CN system approach provides reasonable accuracy and it over performs the previous methods based on the determination of a single asymptotic CN value. Although the suggested method increases the number of unknown parameters to three (instead of one), a clear physical reasoning for them is presented.

  3. SCS-CN parameter determination using rainfall-runoff data in heterogeneous watersheds – the two-CN system approach

    Directory of Open Access Journals (Sweden)

    J. D. Valiantzas

    2012-03-01

    Full Text Available The Soil Conservation Service Curve Number (SCS-CN approach is widely used as a simple method for predicting direct runoff volume for a given rainfall event. The CN parameter values corresponding to various soil, land cover, and land management conditions can be selected from tables, but it is preferable to estimate the CN value from measured rainfall-runoff data if available. However, previous researchers indicated that the CN values calculated from measured rainfall-runoff data vary systematically with the rainfall depth. Hence, they suggested the determination of a single asymptotic CN value observed for very high rainfall depths to characterize the watersheds' runoff response. In this paper, the hypothesis that the observed correlation between the calculated CN value and the rainfall depth in a watershed reflects the effect of soils and land cover spatial variability on its hydrologic response is being tested. Based on this hypothesis, the simplified concept of a two-CN heterogeneous system is introduced to model the observed CN-rainfall variation by reducing the CN spatial variability into two classes. The behaviour of the CN-rainfall function produced by the simplified two-CN system is approached theoretically, it is analysed systematically, and it is found to be similar to the variation observed in natural watersheds. Synthetic data tests, natural watersheds examples, and detailed study of two natural experimental watersheds with known spatial heterogeneity characteristics were used to evaluate the method. The results indicate that the determination of CN values from rainfall runoff data using the proposed two-CN system approach provides reasonable accuracy and it over performs the previous methods based on the determination of a single asymptotic CN value. Although the suggested method increases the number of unknown parameters to three (instead of one, a clear physical reasoning for them is presented.

  4. The Possible Interstellar Anion CH2CN-: Spectroscopic Constants, Vibrational Frequencies, and Other Considerations

    Science.gov (United States)

    Fortenberry, Ryan C.; Crawford, T. Daniel; Lee, Timothy J.

    2013-01-01

    The A\\ ^1B_1 \\leftarrow \\tilde{X}\\ ^1A^{\\prime } excitation into the dipole-bound state of the cyanomethyl anion (CH2CN-) has been hypothesized as the carrier for one diffuse interstellar band. However, this particular molecular system has not been detected in the interstellar medium even though the related cyanomethyl radical and the isoelectronic ketenimine molecule have been found. In this study, we are employing the use of proven quartic force fields and second-order vibrational perturbation theory to compute accurate spectroscopic constants and fundamental vibrational frequencies for \\tilde{X}\\ ^1A^{\\prime } CH2CN- in order to assist in laboratory studies and astronomical observations.

  5. Identifying Multiple Populations in M71 using CN

    Science.gov (United States)

    Gerber, Jeffrey M.; Friel, Eileen D.; Vesperini, Enrico

    2018-01-01

    It is now well established that globular clusters (GCs) host multiple stellar populations characterized by differences in several light elements. While these populations have been found in nearly all GCs, we still lack an entirely successful model to explain their formation. A key constraint to these models is the detailed pattern of light element abundances seen among the populations; different techniques for identifying these populations probe different elements and do not always yield the same results. We study a large sample of stars in the GC M71 for light elements C and N, using the CN and CH band strength to identify multiple populations. Our measurements come from low-resolution spectroscopy obtained with the WIYN-3.5m telescope for ~150 stars from the tip of the red-giant branch down to the main-sequence turn-off. The large number of stars and broad spatial coverage of our sample (out to ~3.5 half-light radii) allows us to carry out a comprehensive characterization of the multiple populations in M71. We use a combination of the various spectroscopic and photometric indicators to draw a more complete picture of the properties of the populations and to investigate the consistency of classifications using different techniques.

  6. Identification of a potential superhard compound ReCN

    International Nuclear Information System (INIS)

    Fan, Xiaofeng; Li, M.M.; Singh, David J.; Jiang, Qing; Zheng, W.T.

    2015-01-01

    Highlights: • We identify a new ternary compound ReCN with theoretical calculation. • The ternary compound ReCN is with two stable structures with P63mc and P3m1. • ReCN is a semiconductor from the calculation of electronic structures. • ReCN is found to possess the outstanding mechanical properties. • ReCN may be synthesized relatively easily. - Abstract: We identify a new ternary compound, ReCN and characterize its properties including structural stability and indicators of hardness using first principles calculations. We find that there are two stable structures with space groups P63mc (HI) and P3m1 (HII), in which there are no C–C and N–N bonds. Both structures, H1 and III are elastically and dynamically stable. The electronic structures show that ReCN is a semiconductor, although the parent compounds, ReC 2 and ReN 2 are both metallic. ReCN is found to possess the outstanding mechanical properties with the large bulk modulus, shear modulus and excellent ideal strengths. In addition, ReCN may perhaps be synthesized relatively easily because it becomes thermodynamic stable with respect to decomposition at very low pressures

  7. Depths of formation of the CN molecule lines in the solar atmosphere

    International Nuclear Information System (INIS)

    Porfir'eva, G.A.

    1975-01-01

    The depths of production of lines of weak bands of the CN molecule violet (lambda=4216A) system are calculated by the weight function method. Two models of solar atmosphere are used. Lines with the different rotational vibrational quantum numbers are produced practically in the same layer (tau approximately equal to 0.05-0.06). The difference of depths of production of the line center and the wing is small (Δtau 0 =0.005). The contribution functions for the solar disk center differ little from those for the edge. The calculations carried out are in good agreement with the results obtained from earlier observations

  8. Nanomechanical properties of TiCN and TiCN/Ti coatings on Ti prepared by Filtered Arc Deposition

    International Nuclear Information System (INIS)

    Sun, Yong; Lu, Cheng; Yu, Hailiang; Kiet Tieu, A.; Su, Lihong; Zhao, Yue; Zhu, Hongtao; Kong, Charlie

    2015-01-01

    Monolayer TiCN and multilayer TiCN/Ti coatings were deposited on the surface of Ti using the Filtered Arc Deposition System (FADS). Nanoindentation tests were performed on both coatings. The multilayer TiCN/Ti coating exhibited better ductility than the monolayer TiCN coating. The lattice constants of the coatings were characterized by X-ray diffraction. Transmission Electron Microscopy (TEM) was used to investigate the fracture behavior of the coatings. Inter-columnar, inclined and lateral cracks were found to be the dominant crack modes in the monolayer TiCN coatings while small bending crack and radial crack were the dominant crack modes in the multilayer TiCN/Ti coatings. The Finite Element Method (FEM) was used to simulate the indentation process. It was found that the Ti interlayer in the multilayer TiCN/Ti coating could efficiently suppress the fracture, which is responsible for the improved ductility of the multilayer TiCN/Ti coating

  9. Thermophysical properties of the ionic liquids [EMIM][B(CN)4] and [HMIM][B(CN)4].

    Science.gov (United States)

    Koller, Thomas M; Rausch, Michael H; Ramos, Javier; Schulz, Peter S; Wasserscheid, Peter; Economou, Ioannis G; Fröba, Andreas P

    2013-07-18

    In the present study, the thermophysical properties of the tetracyanoborate-based ionic liquids (ILs) 1-ethyl-3-methylimidazolium tetracyanoborate ([EMIM][B(CN)4]) and 1-hexyl-3-methylimidazolium tetracyanoborate ([HMIM][B(CN)4]) obtained by both experimental methods and molecular dynamics (MD) simulations are presented. Conventional experimental techniques were applied for the determination of refractive index, density, interfacial tension, and self-diffusion coefficients for [HMIM][B(CN)4] at atmospheric pressure in the temperature range from 283.15 to 363.15 K. In addition, surface light scattering (SLS) experiments provided accurate viscosity and interfacial tension data. As no complete molecular parametrization was available for the MD simulations of [HMIM][B(CN)4], our recently developed united-atom force field for [EMIM][B(CN)4] was partially transferred to the homologous IL [HMIM][B(CN)4]. Deviations between our simulated and experimental data for the equilibrium properties are less than ±0.3% in the case of density and less than ±8% in the case of interfacial tension for both ILs. Furthermore, the calculated and measured data for the transport properties viscosity and self-diffusion coefficient are in good agreement, with deviations of less than ±30% over the whole temperature range. In addition to a comparison with the literature, the influence of varying cation chain length on thermophysical properties of [EMIM][B(CN)4] and [HMIM][B(CN)4] is discussed.

  10. Development of LIFE4-CN: a combined code for steady-state and transient analyses of advanced LMFBR fuels

    International Nuclear Information System (INIS)

    Liu, Y.Y.; Zawadzki, S.; Billone, M.C.; Nayak, U.P.; Roth, T.

    1979-01-01

    The methodology used to develop the LMFBR carbide/nitride fuels code, LIFE4-CN, is described in detail along with some subtleties encountered in code development. Fuel primary and steady-state thermal creep have been used as an example to illustrate the need for physical modeling and the need to recognize the importance of the materials characteristics. A self-consistent strategy for LIFE4-CN verification against irradiation data has been outlined with emphasis on the establishment of the gross uncertainty bands. These gross uncertainty bands can be used as an objective measure to gauge the overall success of the code predictions. Preliminary code predictions for sample steady-state and transient cases are given

  11. A critical quantum chemical and experimental study of the potentiality of direct labeling of the CN group with [99mTc(CO)3]+ or [186/188Re(CO)3]+ in CN containing biomolecules

    International Nuclear Information System (INIS)

    Safi, Benasser; Mertens, John; Kersemans, Ken; Geerlings, Paul

    2008-01-01

    Introduction: It was determined recently that [ 99m Tc(OH 2 ) 2 (X - )(CO 3 ) 3 ] could strongly bind to the CN group, allowing direct labeling of CN in vitamin B 12 despite the presence of a benzimidazole group. The aim of this paper was to perform a critical study of this potentiality, coupling quantum chemical calculations to experimental evidence. Methods: Computational methods: Within the density functional theory calculations, the 6-31+G** basis set (C, H, O, N atoms) and the LANL2DZ basis set (Tc,Re) were used. Stability calculations of the [RCNM(CO) 3 ] + ) (M=Tc,Re) complexes were performed with the Gaussian 03 suite of programs, while for the evaluation of relative stability substitution reactions were used. Radiochemistry: Vitamin B 12 , 4-hydroxy-benzylcyanide and 4-methoxy-benzonitrile were labeled at 100 deg. C during 30 min. High-performance liquid chromatography analysis was performed using radioactive and UV detection. Results: Computational methods: The influence of different ligands on the stability yielded a sequence: imidazole>tBuCN>NH 3 ∼CH 3 CN>HCN (mimicking the best CoCN)>H 2 O. The transmetalation reaction indicates that all ligands prefer Re to Tc. The preference for the nitrogen atom of imidazole to the cyanide nitrogen atom for complex formation with [Tc(CO) 3 (H 2 O) 3 ] + is interpreted in terms of the hard and soft acid and base properties principle. Radiochemistry: 4-Hydroxy-benzylcyanide and 4-methoxy-benzonitrile did not show any labeling. An excess of acetonitrile did not inhibit the labeling of vitamin B 12 as expected if the CN group should be involved, indicating that the labeling occurs on a stronger complexing group present like benzimidazole. Conclusion: Both theory and experiments prove that [CN-Tc(CO) 3 (H 2 O) (2-x) L x ] + complexes are weak and that in vitamin B 12 most probably the benzimidazole group is involved

  12. Seismotectonic models and CN algorithm: The case of Italy

    International Nuclear Information System (INIS)

    Costa, G.; Orozova Stanishkova, I.; Panza, G.F.; Rotwain, I.M.

    1995-07-01

    The CN algorithm is here utilized both for the intermediate term earthquake prediction and to validate the seismotectonic model of the Italian territory. Using the results of the analysis, made through the CN algorithm and taking into account the seismotectonic model, three areas, one for Northern Italy, one for Central Italy and one for Southern Italy, are defined. Two transition areas, between the three main areas are delineated. The earthquakes which occurred in these two areas contribute to the precursor phenomena identified by the CN algorithm in each main area. (author). 26 refs, 6 figs, 2 tabs

  13. <strong>Mini-project>

    DEFF Research Database (Denmark)

    Katajainen, Jyrki

    2008-01-01

    In this project the goal is to develop the safe * family of containers for the CPH STL. The containers to be developed should be safer and more reliable than any of the existing implementations. A special focus should be put on strong exception safety since none of the existing prototypes available...

  14. The effect of Ti(CN/TiNb(CN coating on erosion–corrosion resistance

    Directory of Open Access Journals (Sweden)

    William Aperador Chaparro

    2012-05-01

    Full Text Available The goal of this work was to study electrochemical behaviour in corrosion-erosion conditions for Ti(CN/TiNb(CN multilayer coatings having 1, 50, 100, 150 and 200 bilayer periods on AISI 4140 steel substrates by using a multi-target magnetron reactive sputtering device, with an r.f. source (13.56 MHz, two cylindrical magnetron cathodes and two stoichiometric TiC and Nb targets. The multi-layers were evaluated by comparing them to corrosion, erosion and erosion corrosion for a 30º impact angle in a solution of 0.5 M NaCl and silica, analysing the effect of impact angle and the number of bilayers on these coatings’ corrosion resistance. The electrochemical characterisation was performed using electrochemical impedance spectroscopy for analysing corrosion surface; surface morphology was characterised by using a high-resolution scanning electron microscope (SEM. The results showed a de-creased corrosion rate for multilayer systems tested at 30°.

  15. The influence of the pyrolysis temperature on the electrochemical behavior of carbon-rich SiCN polymer-derived ceramics as anode materials in lithium-ion batteries

    Science.gov (United States)

    Reinold, Lukas Mirko; Yamada, Yuto; Graczyk-Zajac, Magdalena; Munakata, Hirokazu; Kanamura, Kiyoshi; Riedel, Ralf

    2015-05-01

    Within this study we report on the impact of the pyrolysis temperature on the structural and electrochemical properties of the poly(phenylvinylsilylcarbodiimide) derived silicon carbonitride (SiCN) ceramic. Materials pyrolysed at 800 °C and 1300 °C, SiCN 800 and SiCN 1300, are found amorphous. Raman spectroscopy measurements indicate the increase in ordering of the free carbon phase with increasing pyrolysis temperature which leads to lower capacity recovered by SiCN 1300. Significant hysteresis is found for materials pyrolysed at 800 °C during electrochemical lithium insertion/extraction. This feature is attributed to much higher hydrogen content in SiCN 800 sample. An aging of SiCN 800 reflected by a change of elemental composition upon contact to air and a strong film formation are attenuated at a higher pyrolysis temperature. Single particle microelectrode investigation on SiCN 800 and SiCN 1300 clarify different electrochemical behavior of the materials. Much lower charge transfer resistance of SiCN 1300 in comparison to SiCN 800 explains better high currents electrochemical performance. Lithium ions diffusion coefficient Dmin ranges from 3.2 10-9 cm2s-1 to 6.4 10-11 cm2s-1 and is independent on the potential.

  16. Solvent control of charge transfer excited state relaxation pathways in [Fe(2,2 '-bipyridine)(CN)4]2-

    DEFF Research Database (Denmark)

    Kjær, Kasper Skov; Kunnus, Kristjan; Harlang, Tobias C. B.

    2018-01-01

    The excited state dynamics of solvated [Fe(bpy)(CN)4]2-, where bpy = 2,2'-bipyridine, show significant sensitivity to the solvent Lewis acidity. Using a combination of optical absorption and X-ray emission transient spectroscopies, we have previously shown that the metal to ligand charge transfer...... the MLCT excited state relaxation dynamics of [Fe(bpy)(CN)4]2- in water, a strong Lewis acid solvent. The charge-transfer excited state is now found to decay in less than 100 femtoseconds, forming a quasi-stable metal centered excited state with a 13 picosecond lifetime. We find that this MC excited state...... developed for solar applications....

  17. Strong interactions

    International Nuclear Information System (INIS)

    Froissart, Marcel

    1976-01-01

    Strong interactions are introduced by their more obvious aspect: nuclear forces. In hadron family, the nucleon octet, OMEGA - decuplet, and quark triply are successively considered. Pion wave having been put at the origin of nuclear forces, low energy phenomena are described, the force being explained as an exchange of structure corresponding to a Regge trajectory in a variable rotating state instead of the exchange of a well defined particle. At high energies the concepts of pomeron, parton and stratons are introduced, pionization and fragmentation are briefly differentiated [fr

  18. Review IPEEE C.N. external event Vandellos II

    International Nuclear Information System (INIS)

    Hernandez, H.; Gasca, C.; Beltran, F.; Salvat, M.; Pifarre, D.; Canadell, F.; Aleman, A.

    2010-01-01

    Within the process of maintaining and updating the risk analysis of CN Vandellos II, results from the review of the study of vulnerability of the plant against severe accidents caused by external events (Individual Plant Examination on Extornal Events, IPEEE).

  19. NbCN Josephson junctions with AlN barriers

    International Nuclear Information System (INIS)

    Thomasson, S.L.; Murduck, J.M.; Chan, H.

    1991-01-01

    This paper reports on niobium carbonitride (NbCN) Josephson circuits which operate over a wider temperature range than either niobium or niobium nitride circuits. Higher operating temperature places NbCN technology more comfortably within the range of closed cycle refrigerators, a key factor in aerospace applications. We have fabricated tunnel junctions from NbCN films with transition temperatures up to 18 Kelvin. High quality NbCN tunnel junction fabrication generally requires low stress films with roughness less than the barrier thickness (∼20 Angstrom). We have developed scanning tunneling microscopy as a tool for measuring and optimizing film smoothness. Junctions formed in situ with AIN tunneling barriers show reproducible I-V characteristics

  20. Synthesis, spectroscopic, thermal and structural properties of [M(3-aminopyridine)2Ni(μ-CN)2(CN)2]n (M(II) = Co and Cu) heteropolynuclear cyano-bridged complexes

    Science.gov (United States)

    Kartal, Zeki

    2016-01-01

    Two novel cyano-bridged heteropolynuclear complexes, [Co(3-aminopyridine)2Ni(μ-CN)2(CN)2]n and [Cu(3-aminopyridine)2Ni(μ-CN)2(CN)2]n have been synthesized and characterized by elemental, thermal, FT-IR and FT-Raman spectroscopies. The structures of complexes have been determined by X-ray powder diffraction. The FT-IR and FT-Raman spectra of complexes have been recorded in the region of 3500-400 cm-1 and 3500-100 cm-1, respectively. General information was acquired about structural properties of these complexes from FT-IR and FT-Raman spectra by considering changes at characteristic peaks of the cyano group and 3AP. The splitting of the ν(Ctbnd N) stretching bands in the FT-IR spectra for complexes indicates the presence of terminal and bridging cyanides. The thermal behaviors of these complexes have been also investigated in the range of 25-950 °C using TG and DTG methods. Magnetic susceptibility measurements were made at room temperature using Gouy-balance.

  1. Copper (I) Selenocyanate (CuSeCN) as a Novel Hole-Transport Layer for Transistors, Organic Solar Cells, and Light-Emitting Diodes

    KAUST Repository

    Wijeyasinghe, Nilushi; Tsetseris, Leonidas; Regoutz, Anna; Sit, Wai-Yu; Fei, Zhuping; Du, Tian; Wang, Xuhua; McLachlan, Martyn A.; Vourlias, George; Patsalas, Panos A.; Payne, David J.; Heeney, Martin; Anthopoulos, Thomas D.

    2018-01-01

    The synthesis and characterization of copper (I) selenocyanate (CuSeCN) and its application as a solution-processable hole-transport layer (HTL) material in transistors, organic light-emitting diodes, and solar cells are reported. Density-functional theory calculations combined with X-ray photoelectron spectroscopy are used to elucidate the electronic band structure, density of states, and microstructure of CuSeCN. Solution-processed layers are found to be nanocrystalline and optically transparent (>94%), due to the large bandgap of ≥3.1 eV, with a valence band maximum located at −5.1 eV. Hole-transport analysis performed using field-effect measurements confirms the p-type character of CuSeCN yielding a hole mobility of 0.002 cm2 V−1 s−1. When CuSeCN is incorporated as the HTL material in organic light-emitting diodes and organic solar cells, the resulting devices exhibit comparable or improved performance to control devices based on commercially available poly(3,4-ethylenedioxythiophene):polystyrene sulfonate as the HTL. This is the first report on the semiconducting character of CuSeCN and it highlights the tremendous potential for further developments in the area of metal pseudohalides.

  2. Copper (I) Selenocyanate (CuSeCN) as a Novel Hole-Transport Layer for Transistors, Organic Solar Cells, and Light-Emitting Diodes

    KAUST Repository

    Wijeyasinghe, Nilushi

    2018-02-01

    The synthesis and characterization of copper (I) selenocyanate (CuSeCN) and its application as a solution-processable hole-transport layer (HTL) material in transistors, organic light-emitting diodes, and solar cells are reported. Density-functional theory calculations combined with X-ray photoelectron spectroscopy are used to elucidate the electronic band structure, density of states, and microstructure of CuSeCN. Solution-processed layers are found to be nanocrystalline and optically transparent (>94%), due to the large bandgap of ≥3.1 eV, with a valence band maximum located at −5.1 eV. Hole-transport analysis performed using field-effect measurements confirms the p-type character of CuSeCN yielding a hole mobility of 0.002 cm2 V−1 s−1. When CuSeCN is incorporated as the HTL material in organic light-emitting diodes and organic solar cells, the resulting devices exhibit comparable or improved performance to control devices based on commercially available poly(3,4-ethylenedioxythiophene):polystyrene sulfonate as the HTL. This is the first report on the semiconducting character of CuSeCN and it highlights the tremendous potential for further developments in the area of metal pseudohalides.

  3. Li dynamics in carbon-rich polymer-derived SiCN ceramics probed by NMR

    Science.gov (United States)

    Baek, Seung-Ho; Reinold, Lukas; Graczyk-Zajac, Magdalena; Riedel, Ralf; Hammerath, Franziska; Buechner, Bernd; Grafe, Hajo

    2014-03-01

    We report 7Li, 29Si, and 13C NMR studies of two different carbon-rich SiCN ceramics SiCN-1 and SiCN-3 derived from the preceramic polymers polyphenylvinylsilylcarbodiimide and polyphenylvinylsilazane, respectively. From the spectral analysis of the three nuclei at room temperature, we find that only the 13C spectrum is strongly influenced by Li insertion/extraction, suggesting that carbon phases are the major electrochemically active sites for Li storage. Temperature and Larmor frequency (ωL) dependences of the 7Li linewidth and spin-lattice relaxation rates T1-1 are described by an activated law with the activation energy EA of 0.31 eV and the correlation time τ0 in the high temperature limit of 1.3 ps. The 3 / 2 power law dependence of T1-1 on ωL which deviates from the standard Bloembergen, Purcell, and Pound (BPP) model implies that the Li motion on the μs timescale is governed by continuum diffusion mechanism rather than jump diffusion. On the other hand, the rotating frame relaxation rate T1ρ-1 results suggest that the slow motion of Li on the ms timescale may be affected by complex diffusion and/or non-diffusion processes.

  4. Formation of Nitriles in the Interstellar Medium via Reactions of Cyano Radicals, CN(X2Σ+), with Unsaturated Hydrocarbons

    Science.gov (United States)

    Balucani, N.; Asvany, O.; Huang, L. C. L.; Lee, Y. T.; Kaiser, R. I.; Osamura, Y.; Bettinger, H. F.

    2000-12-01

    ; since CH3CCH is the common precursor to H2CCCH(CN)/CH3CCCN and the latter isomer has been assigned unambiguously toward TMC-1 and OMC-1, H2CCCH(CN) is strongly expected to be present in both clouds as well. The formation of isonitrile isomers was not observed in our experiments. Since all reactions to HCCNC, C2H3NC, CH3CCNC, H2CCCH(NC), H2CCC(NC)(CH3), and C6H5NC are either endothermic or the exit barrier is well above the energy of the reactants, neutral-neutral reactions of cyano radicals with closed shell unsaturated hydrocarbons cannot synthesize isonitriles in cold molecular clouds. However, in outflow of carbon stars, the enhanced translational energy of both reactants close to the photosphere of the central star can compensate this endothermicity, and isonitriles might be formed in these hotter environments as well.

  5. 7 CFR Appendix C to Part 226 - Child Nutrition (CN) Labeling Program

    Science.gov (United States)

    2010-01-01

    ...). EC17SE91.009 (c) The CN label statement includes the following: (1) The product identification number... 7 Agriculture 4 2010-01-01 2010-01-01 false Child Nutrition (CN) Labeling Program C Appendix C to.... C Appendix C to Part 226—Child Nutrition (CN) Labeling Program 1. The Child Nutrition (CN) Labeling...

  6. 7 CFR Appendix C to Part 225 - Child Nutrition (CN) Labeling Program

    Science.gov (United States)

    2010-01-01

    ...). EC17SE91.006 (c) The CN label statement includes the following: (1) The product identification number... 7 Agriculture 4 2010-01-01 2010-01-01 false Child Nutrition (CN) Labeling Program C Appendix C to... Appendix C to Part 225—Child Nutrition (CN) Labeling Program 1. The Child Nutrition (CN) Labeling Program...

  7. Spectral line survey toward the spiral arm of M51 in the 3 and 2 mm bands

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Yoshimasa; Sakai, Nami; Yamamoto, Satoshi [Department of Physics, The University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Sorai, Kazuo, E-mail: nabe@taurus.phys.s.u-tokyo.ac.jp [Department of Physics/Department of Cosmoscience, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810 (Japan)

    2014-06-10

    We have conducted a spectral line survey in the 3 and 2 mm bands toward two positions in a spiral arm of M51 (NGC 5194) with the Institut de Radioastronomie Millimétrique 30 m telescope. In this survey, we have identified 13 molecular species, including CN, CCH, N{sub 2}H{sup +}, HNCO, and CH{sub 3}OH. Furthermore, six isotopologues of the major species have been detected. On the other hand, SiO, HC{sub 3}N, CH{sub 3}CN, and deuterated species such as DCN and DCO{sup +} were not detected. The deuterium fractionation ratios are evaluated to be less than 0.8% and 1.2% for DCN/HCN and DCO{sup +}/HCO{sup +}, respectively. By comparing the results of the two positions with different star formation activities, we have found that the observed chemical compositions do not strongly depend on star formation activities. They seem to reflect a chemical composition averaged over the 1 kpc scale region including many giant molecular clouds. Among the detected molecules CN, CCH, and CH{sub 3}OH are found to be abundant. High abundances of CN and CCH are consistent with the above picture of a widespread distribution of molecules because they can be produced by photodissociation. On the other hand, it seems likely that CH{sub 3}OH is liberated in the gas phase by shocks associated with large-scale phenomena such as cloud-cloud collisions and/or by nonthermal desorption processes such as photoevaporation due to cosmic-ray-induced UV photons. The present result demonstrates a characteristic chemical composition of a giant molecular cloud complex in the spiral arm, which can be used as a standard reference for studying chemistry in active galactic nuclei and starbursts.

  8. THE POSSIBLE INTERSTELLAR ANION CH{sub 2}CN{sup -}: SPECTROSCOPIC CONSTANTS, VIBRATIONAL FREQUENCIES, AND OTHER CONSIDERATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Fortenberry, Ryan C.; Lee, Timothy J. [NASA Ames Research Center, Moffett Field, CA 94035-1000 (United States); Crawford, T. Daniel, E-mail: Ryan.C.Fortenberry@nasa.gov, E-mail: Timothy.J.Lee@nasa.gov [Department of Chemistry, Virginia Tech, Blacksburg, VA 24061 (United States)

    2013-01-10

    The A {sup 1}B{sub 1} Leftwards-Open-Headed-Arrow X-tilde{sup 1}A' excitation into the dipole-bound state of the cyanomethyl anion (CH{sub 2}CN{sup -}) has been hypothesized as the carrier for one diffuse interstellar band. However, this particular molecular system has not been detected in the interstellar medium even though the related cyanomethyl radical and the isoelectronic ketenimine molecule have been found. In this study, we are employing the use of proven quartic force fields and second-order vibrational perturbation theory to compute accurate spectroscopic constants and fundamental vibrational frequencies for X-tilde{sup 1} A' CH{sub 2}CN{sup -} in order to assist in laboratory studies and astronomical observations.

  9. Hydrothermal syntheses, structural, Raman, and luminescence studies of Cm[M(CN)2]3.3H2O and Pr[M(CN)2]3.3H2O (M=Ag, Au)

    International Nuclear Information System (INIS)

    Assefa, Zerihun; Haire, Richard G.; Sykora, Richard E.

    2008-01-01

    We have prepared Cm[Au(CN) 2 ] 3 .3H 2 O and Cm[Ag(CN) 2 ] 3 .3H 2 O as a part of our continuing investigations into the chemistry of the 5f-elements' dicyanometallates. Single crystals of Cm[Au(CN) 2 ] 3 .3H 2 O were obtained from the reaction of CmCl 3 and KAu(CN) 2 under mild hydrothermal conditions. Due to similarities in size, the related praseodymium compounds were also synthesized and characterized for comparison with the actinide systems. The compounds crystallize in the hexagonal space group P6 3 /mcm, where the curium and the transition metals interconnect through cyanide bridging. Crystallographic data (Mo Kα, λ=0.71073 A): Cm[Au(CN) 2 ] 3 .3H 2 O (1), a=6.6614(5) A, c=18.3135(13) A, V=703.77(9), Z=2; Pr[Au(CN) 2 ] 3 .3H 2 O (3), a=6.6662(8) A, c=18.497(3) A, V=711.83(17), Z=2; Pr[Ag(CN) 2 ] 3 .3H 2 O (4), a=6.7186(8) A, c=18.678(2) A, V=730.18(14), Z=2. The Cm 3+ and/or Pr 3+ ions are coordinated to six N-bound CN - groups resulting in a trigonal prismatic arrangement. Three oxygen atoms of coordinated water molecules tricap the trigonal prismatic arrangement providing a coordination number of nine for the f-elements. The curium ions in both compounds exhibit a strong red emission corresponding to the 6 D 7/2 → 8 S 7/2 transition. This transition is observed at 16,780 cm -1 , with shoulders at 17,080 and 16,840 cm -1 for the Ag complex, while the emission is red shifted by ∼100 cm -1 in the corresponding gold complex. The Pr systems also provide well-resolved emissions upon f-f excitation. - Graphical abstract: Coordination polymeric compounds between a trans-plutonium element, curium and transition metal ions, gold(I) and silver(I), were prepared using the hydrothermal synthetic procedure. The curium ion and the transition metals are interconnected through cyanide bridging. The Cm ion has a tricapped trigonal prismatic coordination environment with coordination number of nine. Detail photoluminescence studies of the complexes are also reported

  10. Bacterial Electrocatalysis of K4[Fe(CN)6] Oxidation

    DEFF Research Database (Denmark)

    Zheng, Zhiyong; Xiao, Yong; Wu, Ranran

    Shewanella oneidensis MR-1 (MR-1), a model strain of electrochemically active bacteria, can transfer electrons from cell to extracellular electron acceptors including Fe(III) (hydro)oxides. It has been reported that several redox species such as cytochromes in membranes and flavins assist...... in the electron transport (ET) processes. However, the oxidization of metal compounds was barely described. Here we report electrocatalysis of K4[Fe(CN)6] oxidation by MR-1. K4[Fe(CN)6] is a redox inorganic compound and shows a reversible redox process on bare glassy carbon (GCE). This is reflected by a pair...

  11. Exotic Quantum Phases and Phase Transitions of Strongly Interacting Electrons in Low-Dimensional Systems

    Science.gov (United States)

    Mishmash, Ryan V.

    Experiments on strongly correlated quasi-two-dimensional electronic materials---for example, the high-temperature cuprate superconductors and the putative quantum spin liquids kappa-(BEDT-TTF)2Cu2(CN)3 and EtMe3Sb[Pd(dmit)2]2---routinely reveal highly mysterious quantum behavior which cannot be explained in terms of weakly interacting degrees of freedom. Theoretical progress thus requires the introduction of completely new concepts and machinery beyond the traditional framework of the band theory of solids and its interacting counterpart, Landau's Fermi liquid theory. In full two dimensions, controlled and reliable analytical approaches to such problems are severely lacking, as are numerical simulations of even the simplest of model Hamiltonians due to the infamous fermionic sign problem. Here, we attempt to circumvent some of these difficulties by studying analogous problems in quasi-one dimension. In this lower dimensional setting, theoretical and numerical tractability are on much stronger footing due to the methods of bosonization and the density matrix renormalization group, respectively. Using these techniques, we attack two problems: (1) the Mott transition between a Fermi liquid metal and a quantum spin liquid as potentially directly relevant to the organic compounds kappa-(BEDT-TTF)2Cu 2(CN)3 and EtMe3Sb[Pd(dmit)2] 2 and (2) non-Fermi liquid metals as strongly motivated by the strange metal phase observed in the cuprates. In both cases, we are able to realize highly exotic quantum phases as ground states of reasonable microscopic models. This lends strong credence to respective underlying slave-particle descriptions of the low-energy physics, which are inherently strongly interacting and also unconventional in comparison to weakly interacting alternatives. Finally, working in two dimensions directly, we propose a new slave-particle theory which explains in a universal way many of the intriguing experimental results of the triangular lattice organic spin

  12. Enhanced Rate Capability of Polymer-Derived SiCN Anode Material for Electrochemical Storage of Lithium with 3-D Carbon Nanotube Network Dispersed in Nanoscale.

    Science.gov (United States)

    Zhang, Junwei; Xu, Caihong; Liu, Zhaoping; Wang, Wei; Xin, Xing; Shen, Lu; Zhou, Xiaobing; Zhou, Jie; Huang, Qing

    2015-04-01

    Electrochemical performances of multi-walled carbon nanotubes (CNT)-SiCN composite have been investigated. The sample was synthesized by a simple ultrasonication assisted method combined with high-temperature pyrolysis and characterized by Fourier transform infrared spectra, Raman spectra, X-ray diffraction, field emission scanning electron microscopy and transmission electronic microscopy. In this composite, CNT were uniformly distributed in the SiCN ceramic matrix, it retained the structural integrity during the polymer-ceramic conversion and had a relatively strong bonding with the SiCN ceramic matrix. When tested as anode in the half cell, the obtained composite exhibited enhanced rate capability and cyclic capacity than that of pristine SiCN powder, CNT and graphite, it could supply a capacity of 222.7 mA h/g when charged at 2000 mA/g, while the SiCN anode showed nearly no capacity even at the low current density of 200 mA/g. It is expected that the CNT-SiCN composite, perhaps the series of CNT-PDC composites, may be prospective candidate for high power applications.

  13. Magnetic structure of molecular magnet Fe[Fe(CN) 6

    Indian Academy of Sciences (India)

    We have studied the magnetic structure of Fe[Fe(CN)6]·4H2O, prepared by precipitation method, using neutron diffraction technique. Temperature dependent DC magnetization study down to 4.2 K shows that the compound undergoes from a high temperature disordered (paramagnetic) to an ordered magnetic phase ...

  14. EST Table: CN379387 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available CN379387 rzhswbb0_004120 10/09/28 99 %/113 aa gb|ADB13006.1| elongation factor-1 alpha [Colias pelidne skinn...eri] 10/09/01 95 %/113 aa FBpp0257399|DyakGE12389-PA 10/08/28 77 %/113 aa R03G5.1d#

  15. Exploring the crystallization landscape of cadmium bis(N-hydroxyethyl, N-isopropyldithiocarbamate), Cd[S2CN(iPr)CH2CH2OH]2

    International Nuclear Information System (INIS)

    Tan, Yee Seng; Halim, Siti Nadiah Abdul; Tiekink, Edward R.T.; Sunway Univ., Bandar Sunway

    2016-01-01

    Crystallization of Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 from ethanol yields the coordination polymer [{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 }.EtOH] ∞ (1) within 3 h. When the solution is allowed to stand for another hour, the needles begin to dissolve and prisms emerge of the supramolecular isomer (SI), binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 .2EtOH (2). These have been fully characterized spectroscopically and by X-ray crystallography. Polymeric 1 has 2-fold symmetry and features dithiocarbamate ligands coordinating two octahedral Cd atoms in a μ 2 κ 2 -tridentate mode. Binuclear 2 is centrosymmetric with two ligands being μ 2 κ 2 -tridentate as for 1 but the other two being κ 2 -chelating leading to square pyramidal geometries. The conversion of the kinetic crystallization product, 1, to thermodynamic 2 is irreversible but transformations mediated by recrystallization (ethanol and acetonitrile) to related literature SI species, namely coordination polymer [{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 3 .MeCN] ∞ and binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 .2H 2 O.2MeCN, are demonstrated, some of which are reversible. Three other crystallization outcomes are described whereby crystal structures were obtained for the 1:2 co-crystal {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 :2[3-(propan-2-yl)-1,3-oxazolidine-2-thione] (3), the salt co-crystal [iPrNH 2 (CH 2 CH 2 OH)] 4 [SO 4 ] 2 {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 (4) and the salt [iPrNH 2 (CH 2 CH 2 OH)]{Cd[S 2 CN(iPr)CH 2 CH 2 OH] 3 } (5). These arise as a result of decomposition/oxidation of the dithiocarbamate ligands. In each of 3 and 4 the binuclear {Cd[S 2 CN(iPr)CH 2 CH 2 OH] 2 } 2 SI, as in 2, is observed strongly suggesting a thermodynamic preference for this form.

  16. Metal dioxides as analogue of SiO2 under strong compression studied by synchrotron XRD and simulations

    Science.gov (United States)

    Liu, H.; Liu, L. L.

    2017-12-01

    The phase transition sequence of SiO2 inducing by high pressure was theoretically predicted as coordination number (CN=6) structures (rutile, pyrite), CN=8 (Pnma) and CN=9 (P-62m) structures, but only the phases up to pyrite structure in SiO2 were observed experimentally up to now. The CN8 phase and CN9 phases of SiO2 were predicted to be stable at least 650 GPa, which is challenging to achieve in the static DAC experiment at present. In other metal dioxide systems, such as TiO2, the ambient rutile and anatase phases first transform to pyrite (CN6), then to the baddeleyite (CN7) phase, to a Pnma (CN8) phase and P-62m(CN9) phase. In this report, under strong compression at room temperature, several metal dioxides were studied experimentally and theoretically, to verify whether this theoretical predicted trend is common transition path under strong compression. This work was supported by Natural Science Foundation of China (11374075), Heilongjiang Province Science Fund for Distinguished Young Scholars (JC201005), Longjiang Scholar, the Fundamental Research Funds for the Central Universities (HIT. BRET1.2010002, HIT. IBRSEM.A.201403).

  17. Dissociative adsorption of environment-friendly insulating medium C3F7CN on Cu(111) and Al(111) surface: A theoretical evaluation

    Science.gov (United States)

    Zhang, Xiaoxing; Li, Yi; Chen, Dachang; Xiao, Song; Tian, Shuangshuang; Tang, Ju; Wang, Dibo

    2018-03-01

    SF6 is extensively used in electrical applications because of its excellent insulation and arc extinguishing performance, but its strong greenhouse effect has negative impact on the atmosphere. The excellent performance of C3F7CN in greenhouse effect, insulation ability, safety, and thermal stability has been demonstrated, indicating that this compound can replace SF6 in electrical applications. However, little information is available on the compatibility of C3F7CN with metals, such as copper and aluminum, in devices. Material compatibility between new gas mixtures and materials used in Gas Insulated Switchgear (GIS) should be investigated to determine the long-term behavior of materials. In this paper, dissociative adsorption of C3F7CN on Cu (1 1 1) and Al (1 1 1) surfaces were analyzed based on density functional theory. Adsorption energy, charge transfer, density of states, and electron density difference of interaction between C3F7CN and two metals were analyzed. It was found that the adsorption energy of C3F7CN adsorbed on Cu (1 1 1) and Al (1 1 1) is both below 0.8 eV. This value indicates that the interaction between them is not very strong. In addition, the dissociation reaction path of gas molecules after adsorption requires certain activation energy. Therefore, C3F7CN and copper or aluminum have certain compatibility and the compatibility of C3F7CN with aluminum is better than that of copper. Related results provide a reference for predicting the aging mechanism of equipment and the selection or modification of major materials for equipment.

  18. Superconductivity at 2.8 K and 1.5 kbar in κ-(BEDT-TTF)2Cu2(CN)3: The first organic superconductor containing a polymeric copper cyanide anion

    International Nuclear Information System (INIS)

    Geiser, Urs; Wang Hau, H.; Carlson, K.D.; Williams, J.M.; Charlier, H.A. Jr.; Heindl, J.E.; Yaconi, G.A.; Love, B.J.; Lathrop, M.W.; Schirber, J.E.; Overmyer, D.L.; Ren, Jingquing; Whangbo, Myung-Hwan

    1991-01-01

    Attempts to synthesize new k-phase superconductors have concentrated on ET salts with complex anions composed of Cu(I) or Ag(I) metal ions and pseudohalide anions. The 'targeted anion approach', by use of a preformed anion found in KCu 2 (CN) 3 .H 2 O and the presence of trace amounts of water, led to the discovery of the first copper-cyanide containing superconductor, K-(ET) 2 Cu 2 (CN) 3 . The crystal structure, superconducting properties, and band electronic structure are described in this article. The complex k-(ET) 2 Cu 2 (CN) 3 is in many ways similar to the superconductor K-(ET) 2 Cu[N(CN) 2 ]Cl, the superconductor with the highest T c reported to date. 28 refs., 3 figs

  19. The CN/C15N isotopic ratio towards dark clouds

    Science.gov (United States)

    Hily-Blant, P.; Pineau des Forêts, G.; Faure, A.; Le Gal, R.; Padovani, M.

    2013-09-01

    Understanding the origin of the composition of solar system cosmomaterials is a central question, not only in the cosmochemistry and astrochemistry fields, and requires various approaches to be combined. Measurements of isotopic ratios in cometary materials provide strong constraints on the content of the protosolar nebula. Their relation with the composition of the parental dark clouds is, however, still very elusive. In this paper, we bring new constraints based on the isotopic composition of nitrogen in dark clouds, with the aim of understanding the chemical processes that are responsible for the observed isotopic ratios. We have observed and detected the fundamental rotational transition of C15N towards two starless dark clouds, L1544 and L1498. We were able to derive the column density ratio of C15N over 13CN towards the same clouds and obtain the CN/C15N isotopic ratios, which were found to be 500 ± 75 for both L1544 and L1498. These values are therefore marginally consistent with the protosolar value of 441. Moreover, this ratio is larger than the isotopic ratio of nitrogen measured in HCN. In addition, we present model calculations of the chemical fractionation of nitrogen in dark clouds, which make it possible to understand how CN can be deprived of 15N and HCN can simultaneously be enriched in heavy nitrogen. The non-fractionation of N2H+, however, remains an open issue, and we propose some chemical way of alleviating the discrepancy between model predictions and the observed ratios. Appendices are available in electronic form at http://www.aanda.orgThe reduced spectra (in FITS format) are available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/557/A65

  20. Synthesis and electrical, spectroscopic and nonlinear optical properties of cobalt molecular materials obtained from PcCo(CN)L (L = ethylenediamine, 1,4-diaminebutane, 1,12-diaminododecane and 2,6-diamineanthraquinone)

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Saavedra, O.G., E-mail: omar.morales@ccadet.unam.mx [Lab. of Nonlinear Optics, Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, CCADET-UNAM, Apdo, Postal 70-186, C.P. 04510 Coyoacan, Cd. Universitaria, Mexico D. F. (Mexico); Sanchez-Vergara, M.E. [Coordinacion de Ingenieria Mecatronica, Facultad de Ingenieria, Universidad Anahuac del Norte, Avenida Universidad Anahuac 46, Col. Lomas Anahuac, 52786 Huixquilucan, Estado de Mexico (Mexico); Rodriguez-Rosales, A.A.; Ortega-Martinez, R. [Lab. of Nonlinear Optics, Centro de Ciencias Aplicadas y Desarrollo Tecnologico, Universidad Nacional Autonoma de Mexico, CCADET-UNAM, Apdo, Postal 70-186, C.P. 04510 Coyoacan, Cd. Universitaria, Mexico D. F. (Mexico); Ortiz-Rebollo, A. [Instituto de Investigaciones en Materiales, Universidad Nacional Autonoma de Mexico, IIM-UNAM, A.P. 70-360 Coyoacan, 04510 Mexico D. F. (Mexico); Frontana-Uribe, B.A. [Centro Conjunto de Investigacion en Quimica Sustentable UAEM-UNAM Km. 14.5, Carretera Toluca-Atlacomulco, C.P. 50200 Toluca, Estado de Mexico (Mexico); Garcia-Montalvo, V. [Instituto de Quimica, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, Mexico D. F. 04510 (Mexico)

    2010-10-01

    Novel PcCo(CN)L monomeric complexes were synthesized from [PcCoCN]{sub n} compounds and bidentate axial ligands (L) such as ethylenediamine, 1,4-diaminebutane, 1,12-diaminedodecane and 2,6-diamineanthraquinone. These complexes were implemented to fabricate pellets and thin films by the vacuum thermal evaporation technique. The obtained compounds and deposited thin films were characterized by different spectroscopic techniques. Measurements of the electrical conductivity and the electrical current as a function of temperature were also carried out. IR-spectroscopy studies showed that the ligand attaches to the [PcCoCN]{sub n} unit. The C=N vibrational band is found in the PcCo(et)CN and PcCo(bu)CN molecular solids, although it is displaced with respect to other reported values. Compounds PcCo(do){sub 2} and PcCo(an){sub 2} do not show C=N vibrational bands. This fact suggests a double bond between the ligand and the macrocycle and a coordination at the fifth and sixth position on the Co(III) atom. UV-vis spectra of the thin films exhibited higher conjugation degree for the CN-based samples. Electrical conductivity for the PcCo(an){sub 2} complex was consistently low for all temperature ranges under measurement, whereas the other synthesized compounds showed a semiconductor-like dependence of electric current with temperature. Additionally, cubic nonlinear optical (NLO) characterizations of the film samples were performed with the Z-Scan and third harmonic generation (THG) techniques, all samples exhibit outstandingly high nonlinear activity.

  1. Synthesis and electrical, spectroscopic and nonlinear optical properties of cobalt molecular materials obtained from PcCo(CN)L (L = ethylenediamine, 1,4-diaminebutane, 1,12-diaminododecane and 2,6-diamineanthraquinone)

    International Nuclear Information System (INIS)

    Morales-Saavedra, O.G.; Sanchez-Vergara, M.E.; Rodriguez-Rosales, A.A.; Ortega-Martinez, R.; Ortiz-Rebollo, A.; Frontana-Uribe, B.A.; Garcia-Montalvo, V.

    2010-01-01

    Novel PcCo(CN)L monomeric complexes were synthesized from [PcCoCN] n compounds and bidentate axial ligands (L) such as ethylenediamine, 1,4-diaminebutane, 1,12-diaminedodecane and 2,6-diamineanthraquinone. These complexes were implemented to fabricate pellets and thin films by the vacuum thermal evaporation technique. The obtained compounds and deposited thin films were characterized by different spectroscopic techniques. Measurements of the electrical conductivity and the electrical current as a function of temperature were also carried out. IR-spectroscopy studies showed that the ligand attaches to the [PcCoCN] n unit. The C=N vibrational band is found in the PcCo(et)CN and PcCo(bu)CN molecular solids, although it is displaced with respect to other reported values. Compounds PcCo(do) 2 and PcCo(an) 2 do not show C=N vibrational bands. This fact suggests a double bond between the ligand and the macrocycle and a coordination at the fifth and sixth position on the Co(III) atom. UV-vis spectra of the thin films exhibited higher conjugation degree for the CN-based samples. Electrical conductivity for the PcCo(an) 2 complex was consistently low for all temperature ranges under measurement, whereas the other synthesized compounds showed a semiconductor-like dependence of electric current with temperature. Additionally, cubic nonlinear optical (NLO) characterizations of the film samples were performed with the Z-Scan and third harmonic generation (THG) techniques, all samples exhibit outstandingly high nonlinear activity.

  2. Using Machine Learning to classify the diffuse interstellar bands

    Science.gov (United States)

    Baron, Dalya; Poznanski, Dovi; Watson, Darach; Yao, Yushu; Cox, Nick L. J.; Prochaska, J. Xavier

    2015-07-01

    Using over a million and a half extragalactic spectra from the Sloan Digital Sky Survey we study the correlations of the diffuse interstellar bands (DIBs) in the Milky Way. We measure the correlation between DIB strength and dust extinction for 142 DIBs using 24 stacked spectra in the reddening range E(B - V) studied before. Most of the DIBs do not correlate with dust extinction. However, we find 10 weak and barely studied DIBs with correlations that are higher than 0.7 with dust extinction and confirm the high correlation of additional five strong DIBs. Furthermore, we find a pair of DIBs, 5925.9 and 5927.5 Å, which exhibits significant negative correlation with dust extinction, indicating that their carrier may be depleted on dust. We use Machine Learning algorithms to divide the DIBs to spectroscopic families based on 250 stacked spectra. By removing the dust dependence, we study how DIBs follow their local environment. We thus obtain six groups of weak DIBs, four of which are tightly associated with C2 or CN absorption lines.

  3. CN emission spectroscopy study of carbon plasma in nitrogen environment

    International Nuclear Information System (INIS)

    Abdelli-Messaci, S.; Kerdja, T.; Bendib, A.; Malek, S.

    2005-01-01

    Spectroscopic emission diagnostics of a carbon plasma created by an excimer KrF laser pulse at three laser fluences (12, 25 and 32 J/cm 2 ) is performed under nitrogen ambient at pressures of 0.5 and 1 mbar. By following the time evolution of the radical CN spectral emission profiles, we notice, at a certain distance from the target surface, the existence of twin peaks for the time of flight distribution. This double structure depends on laser fluence and gas pressure parameters. The first peak moves forward in relation with the plasma expansion whereas the second peak moves backward and it is attributed to CN species undergoing oscillations or reflected shocks

  4. SCS-CN based time-distributed sediment yield model

    Science.gov (United States)

    Tyagi, J. V.; Mishra, S. K.; Singh, Ranvir; Singh, V. P.

    2008-05-01

    SummaryA sediment yield model is developed to estimate the temporal rates of sediment yield from rainfall events on natural watersheds. The model utilizes the SCS-CN based infiltration model for computation of rainfall-excess rate, and the SCS-CN-inspired proportionality concept for computation of sediment-excess. For computation of sedimentographs, the sediment-excess is routed to the watershed outlet using a single linear reservoir technique. Analytical development of the model shows the ratio of the potential maximum erosion (A) to the potential maximum retention (S) of the SCS-CN method is constant for a watershed. The model is calibrated and validated on a number of events using the data of seven watersheds from India and the USA. Representative values of the A/S ratio computed for the watersheds from calibration are used for the validation of the model. The encouraging results of the proposed simple four parameter model exhibit its potential in field application.

  5. Pressure-induced polymerization of P(CN){sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Gou, Huiyang, E-mail: hgou@ciw.edu, E-mail: tstrobel@ciw.edu; Kim, Duck Young; Strobel, Timothy A., E-mail: hgou@ciw.edu, E-mail: tstrobel@ciw.edu [Geophysical Laboratory, Carnegie Institution of Washington, 5251 Broad Branch Road, NW, Washington, DC 20015 (United States); Yonke, Brendan L. [NRC Postdoctoral Associate, Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC 20375 (United States); Epshteyn, Albert [Naval Research Laboratory, 4555 Overlook Ave., SW, Washington, DC 20375 (United States); Smith, Jesse S. [High Pressure Collaborative Access Team, Geophysical Laboratory, Carnegie Institution of Washington, Argonne, Illinois 60439 (United States)

    2015-05-21

    Motivated to explore the formation of novel extended carbon-nitrogen solids via well-defined molecular precursor pathways, we studied the chemical reactivity of highly pure phosphorous tricyanide, P(CN){sub 3}, under conditions of high pressure at room temperature. Raman and infrared (IR) spectroscopic measurements reveal a series of phase transformations below 10 GPa, and several low-frequency vibrational modes are reported for the first time. Synchrotron powder X-ray diffraction measurements taken during compression show that molecular P(CN){sub 3} is highly compressible, with a bulk modulus of 10.0 ± 0.3 GPa, and polymerizes into an amorphous solid above ∼10.0 GPa. Raman and IR spectra, together with first-principles molecular-dynamics simulations, show that the amorphization transition is associated with polymerization of the cyanide groups into CN bonds with predominantly sp{sup 2} character, similar to known carbon nitrides, resulting in a novel phosphorous carbon nitride (PCN) polymeric phase, which is recoverable to ambient pressure.

  6. Elimination Reactions of (E)-2,4,6-Trinitrobenzaldehyde O-benzoyloximes Promoted by R2NH in MeCN. Change of Reaction Mechanism

    International Nuclear Information System (INIS)

    Cho, Bong Rae; Pyun, Sang Yong

    2010-01-01

    We have studied the nitrile-forming elimination reactions from 1 promoted by R 2 NH in MeCN. The reaction proceeded by (E1cb) irr mechanism. Change of the β-aryl group from 2,4-dinitrophenyl to a more strongly electron-withdrawing 2,4,6-trinitrophenyl increased the reaction rate by 470-fold, shifted the transition state toward more reactant-like, and changed the reaction mechanism from E2 to (E1cb) irr . To the best of our knowledge, this is the first example of nitrile-forming elimination reaction that proceeds by the (E1cb) irr mechanism in MeCN. Noteworthy is the carbanion stabilizing ability of the 2,4,6-trinitrophenyl group in aprotic solvent. Nitrile-forming elimination reactions of (E)-benzaldoxime derivatives have been extensively investigated under various conditions. The reactions proceeded by the E2 mechanism in MeCN despite the fact that the reactants have syn stereochemistry, poor leaving, and sp 2 hybridized β-carbon atom, all of which favor E1cb- or E1cb-like transition state. Moreover, the transition state structures were relatively insensitive to the variation of the reactant structures. The results have been attributed to the poor anion solvating ability of MeCN, which favors E2 transition state with maximum charge dispersal. For eliminations from strongly activated (E)-2,4-(NO 2 ) 2 C 6 H 3 CH=NOC(O)C 6 H 4 X, a change in the reaction mechanism from E2 to (E1cb) irr was observed as the base-solvent was changed from R 2 NH in MeCN to R 2 NH/R 2 NH 2 + in 70 mol % MeCN(aq). A combination of a strong electron-withdrawing β-aryl group and anion-solvating protic solvent was required for the mechanistic change

  7. A theoretical study of spectroscopy and metastability of the CN2+ dication

    Czech Academy of Sciences Publication Activity Database

    Fišer, J.; Polák, Rudolf

    2012-01-01

    Roč. 392, č. 1 (2012), s. 55-62 ISSN 0301-0104 Institutional research plan: CEZ:AV0Z40400503 Keywords : CN * CN+ * CN2+ Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 1.957, year: 2012

  8. 7 CFR Appendix C to Part 220 - Child Nutrition (CN) Labeling Program

    Science.gov (United States)

    2010-01-01

    ... product label that contains a CN label statement and CN logo as defined in paragraph 3 (b) and (c) below... statement” as defined in paragraph 3(c). EC17SE91.003 (c) The “CN label statement” includes the following... alternate product toward the meat/meat alternate, bread/bread alternate, and/or vegetable/fruit component of...

  9. 8-12 GHz Radio Observations of Flare Activity On M dwarf CN Leo

    Science.gov (United States)

    Wofford, Alia; Villadsen, Jackie; Quintana, Elisa; Barclay, Thomas; Thackeray, Beverly

    2018-01-01

    Red dwarfs are cool stars that make up 70% of all stars. Red dwarfs can be utilized to detect potentially habitable planets but they have particularly strong magnetic activity that can be detrimental to orbiting planets’ atmospheres and habitability. A coronal mass ejection (CME) is an eruption of magnetized plasma from the star that is ejected into the interplanetary medium which can erode a planet’s atmosphere daily. Based on the sun CMEs are expected to produce very bright radio bursts along with optical flares. We are using M dwarf CN Leo, a well studied flare star that was in the K2 campaign field in summer 2017, as a template to understand the relationship between radio and optical flares and the space weather conditions impacting M dwarf planets. Using radio frequencies ranging from 0.22 GHz-12 GHz we search for simultaneous radio bursts and optical flares to infer if CMEs, flares or aurorae are occurring on the star. I will present the 8-12 GHz radio data from eight 1.5-hour observations with simultaneous optical data. CN Leo produced a bright non-thermal radio flare that lasted approximately for a day during two consecutive observations, with a gyrosynchrotron emission mechanism.

  10. Distinct features of C/N balance regulation in Prochlorococcus sp. strain MIT9313.

    Science.gov (United States)

    Domínguez-Martín, María Agustina; López-Lozano, Antonio; Rangel-Zúñiga, Oriol Alberto; Díez, Jesús; García-Fernández, José Manuel

    2018-02-01

    The abundance and significant contribution to global primary production of the marine cyanobacterium Prochlorococcus have made it one of the main models in marine ecology. Several conditions known to cause strong effects on the regulation of N-related enzymes in other cyanobacteria lacked such effect in Prochlorococcus. Prochlorococcus sp. strain MIT9313 is one of the most early-branching strains among the members of this genus. In order to further understand the C/N control system in this cyanobacterium, we studied the effect of the absence of three key elements in the ocean, namely N, P and Fe, as well as the effect of inhibitors of the N assimilation or photosynthesis on the N metabolism of this strain. Furthermore, we focused our work in the effect of ageing, as the age of cultures has clear effects on the regulation of some enzymes in Prochlorococcus. To reach this goal, expression of the main three regulators involved in N assimilation in cyanobacteria, namely ntcA, glnB and pipX, as well as that of icd (encoding for isocitrate dehydrogenase) were analysed. Our results show that the control of the main proteins involved in the C/N balance in strain MIT9313 differs from other model Prochlorococcus strains. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  11. Polymerization of Acetonitrile via a Hydrogen Transfer Reaction from CH3 to CN under Extreme Conditions.

    Science.gov (United States)

    Zheng, Haiyan; Li, Kuo; Cody, George D; Tulk, Christopher A; Dong, Xiao; Gao, Guoying; Molaison, Jamie J; Liu, Zhenxian; Feygenson, Mikhail; Yang, Wenge; Ivanov, Ilia N; Basile, Leonardo; Idrobo, Juan-Carlos; Guthrie, Malcolm; Mao, Ho-Kwang

    2016-09-19

    Acetonitrile (CH3 CN) is the simplest and one of the most stable nitriles. Reactions usually occur on the C≡N triple bond, while the C-H bond is very inert and can only be activated by a very strong base or a metal catalyst. It is demonstrated that C-H bonds can be activated by the cyano group under high pressure, but at room temperature. The hydrogen atom transfers from the CH3 to CN along the CH⋅⋅⋅N hydrogen bond, which produces an amino group and initiates polymerization to form a dimer, 1D chain, and 2D nanoribbon with mixed sp(2) and sp(3) bonded carbon. Finally, it transforms into a graphitic polymer by eliminating ammonia. This study shows that applying pressure can induce a distinctive reaction which is guided by the structure of the molecular crystal. It highlights the fact that very inert C-H can be activated by high pressure, even at room temperature and without a catalyst. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. 12C(n , 2 n )11C cross section from threshold to 26.5 MeV

    Science.gov (United States)

    Yuly, M.; Eckert, T.; Hartshaw, G.; Padalino, S. J.; Polsin, D. N.; Russ, M.; Simone, A. T.; Brune, C. R.; Massey, T. N.; Parker, C. E.; Fitzgerald, R.; Sangster, T. C.; Regan, S. P.

    2018-02-01

    The 12C(n ,2 n )11C cross section was measured from just below threshold to 26.5 MeV using the Pelletron accelerator at Ohio University. Monoenergetic neutrons, produced via the 3H(d ,n )4He reaction, were allowed to strike targets of polyethylene and graphite. Activation of both targets was measured by counting positron annihilations resulting from the β+ decay of 11C. Annihilation gamma rays were detected, both in coincidence and singly, using back-to-back NaI detectors. The incident neutron flux was determined indirectly via 1H(n ,p ) protons elastically scattered from the polyethylene target. Previous measurements fall into upper and lower bands; the results of the present measurement are consistent with the upper band.

  13. The 12C(n, 2n)11C cross section from threshold to 26.5 MeV.

    Science.gov (United States)

    Yuly, M; Eckert, T; Hartshaw, G; Padalino, S J; Polsin, D N; Russ, M; Simone, A T; Brune, C R; Massey, T N; Parker, C E; Fitzgerald, R; Sangster, T C; Regan, S P

    2018-02-01

    The 12 C(n, 2n) 11 C cross section was measured from just below threshold to 26.5 MeV using the Pelletron accelerator at Ohio University. Monoenergetic neutrons, produced via the 3 H(d,n) 4 He reaction, were allowed to strike targets of polyethylene and graphite. Activation of both targets was measured by counting positron annihilations resulting from the β + decay of 11 C. Annihilation gamma rays were detected, both in coincidence and singly, using back-to-back NaI detectors. The incident neutron flux was determined indirectly via 1 H(n,p) protons elastically scattered from the polyethylene target. Previous measurements fall into upper and lower bands; the results of the present measurement are consistent with the upper band.

  14. Elucidation of C{sub 2} and CN formation mechanisms in laser-induced plasmas through correlation analysis of carbon isotopic ratio

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Meirong [School of Electric Power, South China University of Technology, Guangzhou, Guangdong 510640 (China); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Chan, George C.-Y.; Mao, Xianglei; Gonzalez, Jhanis J. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Lu, Jidong [School of Electric Power, South China University of Technology, Guangzhou, Guangdong 510640 (China); Russo, Richard E., E-mail: RERusso@lbl.gov [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2014-10-01

    Laser ablation molecular isotopic spectrometry (LAMIS) was recently reported for rapid isotopic analysis by measuring molecular emission from laser-induced plasmas at atmospheric pressure. With {sup 13}C-labeled benzoic acid as a model sample, this research utilized the LAMIS approach to clarify the formation mechanisms of C{sub 2} and CN molecules during laser ablation of organic materials. Because the isotopic ratios in the molecular bands could deviate from statistical distribution depending on their formation pathways, the dominant mechanism can be identified through a comparison of the experimental observed isotopic patterns in the molecular emission with the theoretical statistical pattern. For C{sub 2} formation, the experimental {sup 12}C{sup 12}C/{sup 13}C{sup 12}C ratios not only support a recombination mechanism through atomic carbon at early delay time but also indicate the presence of other operating mechanisms as the plasma evolves; it is proposed that some of the C{sub 2} molecules are released directly from the aromatic ring of the sample as molecular fragments. In contrast, the temporal profiles in the {sup 12}C/{sup 13}C ratios derived from CN emission exhibited opposite behavior with those derived from C{sub 2} emission, which unambiguously refutes mechanisms that require C{sub 2} as a precursor for CN formation; CN formation likely involves atomic carbon or species with a single carbon atom. - Highlights: • C{sub 2} and CN formation mechanisms during laser ablation of organic material studied • Some C{sub 2} molecules are directly desorbed from the organic compound. • C{sub 2} molecules are not important precursor for CN-radical formation.

  15. Atomic-Monolayer MoS2 Band-to-Band Tunneling Field-Effect Transistor

    KAUST Repository

    Lan, Yann Wen

    2016-09-05

    The experimental observation of band-to-band tunneling in novel tunneling field-effect transistors utilizing a monolayer of MoS2 as the conducting channel is demonstrated. Our results indicate that the strong gate-coupling efficiency enabled by two-dimensional materials, such as monolayer MoS2, results in the direct manifestation of a band-to-band tunneling current and an ambipolar transport.

  16. Magnetic anisotropy of [Mo(CN)7]4- anions and fragments of cyano-bridged magnetic networks.

    Science.gov (United States)

    Chibotaru, Liviu F; Hendrickx, Marc F A; Clima, Sergiu; Larionova, Joulia; Ceulemans, Arnout

    2005-08-18

    Quantum chemistry calculations of CASSCF/CASPT2 level together with ligand field analysis are used for the investigation of magnetic anisotropy of [Mo(CN)7]4- complexes. We have considered three types of heptacyano environments: two ideal geometries, a pentagonal bipyramid and a capped trigonal prism, and the heptacyanomolybdate fragment of the cyano-bridged magnetic network K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O. At all geometries the first excited Kramers doublet is found remarkably close to the ground one due to a small orbital energy gap in the ligand field spectrum, which ranges between a maximal value in the capped trigonal prism (800 cm(-1)) and zero in the pentagonal bipyramid. The small value of this gap explains (i) the axial form of the g tensor and (ii) the strong magnetic anisotropy even in strongly distorted complexes. Comparison with available experimental data for the g tensor of the mononuclear precursors reveals good agreement with the present calculations for the capped trigonal prismatic complex and a significant discrepancy for the pentagonal bipyramidal one. The calculations for the heptacyanomolybdate fragment of K2[Mn(H2O)2]3[Mo(CN)7]2.6H2O give g(perpendicular)/g(parallel) approximately 0.5 and the orientation of the local anisotropy axis close to the symmetry axis of an idealized pentagonal bipyramid. These findings are expected to be important for the understanding of the magnetism of anisotropic Mo(III)-Mn(II) cyano-bridged networks based on the [Mo(CN)7]4- building block.

  17. THE PECULIAR DISTRIBUTION OF CH{sub 3}CN IN IRC +10216 SEEN BY ALMA

    Energy Technology Data Exchange (ETDEWEB)

    Agúndez, M.; Cernicharo, J.; Quintana-Lacaci, G.; Prieto, L. Velilla [Instituto de Ciencia de Materiales de Madrid, CSIC, C/Sor Juana Inés de la Cruz 3, E-28049 Cantoblanco (Spain); Castro-Carrizo, A.; Guélin, M. [Institut de Radioastronomie Millimétrique, 300 rue de la Piscine, F-38406 St. Martin d’Héres (France); Marcelino, N. [INAF, Istituto di Radioastronomia, via Gobetti 101, I-40129 Bologna (Italy)

    2015-12-01

    IRC +10216 is a circumstellar envelope around a carbon-rich evolved star which contains a large variety of molecules. According to interferometric observations, molecules are distributed either concentrated around the central star or as a hollow shell with a radius of ∼15″. We present ALMA Cycle 0 band 6 observations of the J = 14 – 13 rotational transition of CH{sub 3}CN in IRC +10216, obtained with an angular resolution of 0.″76 × 0.″61. The bulk of the emission is distributed as a hollow shell located at just ∼2″ from the star, with a void of emission in the central region up to a radius of ∼1″. This spatial distribution is markedly different from those found to date in this source for other molecules. Our analysis indicates that methyl cyanide is not formed in either the stellar photosphere or far in the outer envelope, but at radial distances as short as 1″–2″, reaching a maximum abundance of ∼0.02 molecules cm{sup −3} at 2″ from the star. Standard chemical models of IRC +10216 predict that the bulk of CH{sub 3}CN molecules should be present at a radius of ∼15″ where other species such as polyyne radicals and cyanopolyynes are observed, with an additional inner component within 1″ from the star. The non-uniform structure of the circumstellar envelope and grain surface processes are discussed as possible causes of the peculiar distribution of methyl cyanide in IRC +10216.

  18. Dissociation mechanisms and dynamics of doubly charged CD3CN observed by PEPIPICO spectroscopy

    International Nuclear Information System (INIS)

    Harada, C.; Tada, S.; Yamamoto, K.; Senba, Y.; Yoshida, H.; Hiraya, A.; Wada, S.; Tanaka, K.; Tabayashi, K.

    2006-01-01

    Dissociation of free acetonitrile-d 3 molecule, CD 3 CN induced by core level excitation was studied near the nitrogen K-edge by time-of-flight fragment mass spectroscopy. A variety of atomic and molecular fragment cations such as D + , CD n + , C 2 D n + , and CD n CN + were detected using the effusive CD 3 CN beam. Photoelectron-photoion-photoion coincidence technique was applied to analyse the dissociation mechanisms and dynamics of doubly charged CD 3 CN 2+ following the N(1s-π * ) excitation. The charge separation mechanisms of core-excited CD 3 CN were discussed in connection with Auger final state distributions

  19. Prediction of the Iron-Based Polynuclear Magnetic Superhalogens with Pseudohalogen CN as Ligands.

    Science.gov (United States)

    Ding, Li-Ping; Shao, Peng; Lu, Cheng; Zhang, Fang-Hui; Liu, Yun; Mu, Qiang

    2017-07-17

    To explore stable polynuclear magnetic superhalogens, we perform an unbiased structure search for polynuclear iron-based systems based on pseudohalogen ligand CN using the CALYPSO method in conjunction with density functional theory. The superhalogen properties, magnetic properties, and thermodynamic stabilities of neutral and anionic Fe 2 (CN) 5 and Fe 3 (CN) 7 clusters are investigated. The results show that both of the clusters have superhalogen properties due to their electron affinities (EAs) and that vertical detachment energies (VDEs) are significantly larger than those of the chlorine element and their ligand CN. The distribution of the extra electron analysis indicates that the extra electron is aggregated mainly into pseudohalogen ligand CN units in Fe 2 (CN) 5 ¯ and Fe 3 (CN) 7 ¯ cluster. These features contribute significantly to their high EA and VDE. Besides superhalogen properties, these two anionic clusters carry a large magnetic moment just like the Fe 2 F 5 ¯ cluster. Additionally, the thermodynamic stabilities are also discussed by calculating the energy required to fragment the cluster into various smaller stable clusters. It is found that Fe(CN) 2 is the most favorable fragmentation product for anionic Fe 2 (CN) 5 ¯ and Fe 3 (CN) 7 ¯ clusters, and both of the anions are less stable against ejection of Fe atoms than Fe(CN) n-x .

  20. Congenital Constriction Band Syndrome

    OpenAIRE

    Rajesh Gupta, Fareed Malik, Rishabh Gupta, M.A.Basit, Dara Singh

    2008-01-01

    Congenital constriction bands are anomalous bands that encircle a digit or an extremity. Congenitalconstriction band syndrome is rare condition and is mostly associated with other musculoskeletaldisorders.We report such a rare experience.

  1. The rate of the reaction between CN and C2H2 at interstellar temperatures

    Science.gov (United States)

    Woon, D. E.; Herbst, E.

    1997-01-01

    The rate coefficient for the important interstellar reaction between CN and C2H2 has been calculated as a function of temperature between 10 and 300 K. The potential surface for this reaction has been determined through ab initio quantum chemical techniques; the potential exhibits no barrier in the entrance channel but does show a small exit channel barrier, which lies below the energy of reactants. Phase-space calculations for the reaction dynamics, which take the exit channel barrier into account, show the same unusual temperature dependence as determined by experiment, in which the rate coefficient at first increases as the temperature is reduced below room temperature and then starts to decrease as the temperature drops below 50-100 K. The agreement between theory and experiment provides strong confirmation that the reaction occurs appreciably at cool interstellar temperatures.

  2. Soft-mode transition in the ferroelastic crystal K2Hg(CN)4

    International Nuclear Information System (INIS)

    Powell, B.M.; Gerlach, P.N.

    1989-01-01

    Inelastic neutron scattering techniques have been used to investigate the structural transition from the paraelastic to the ferroelastic phase in K 2 Hg(CN) 4 . Several low-frequency phonon branches were measured along the high-symmetry directions and found to be almost independent of temperature. However, a particular low-lying branch along [111] was found to show a strong temperature dependence. The structure factor for this mode shows it to be a longitudinal, librational mode whose eigenvector specifies antiphase rotation of adjacent rigid cyanotetrahedra. This is in agreement with the change in the crystal structure observed at the transition by diffraction measurements. The frequency of this branch at the zone- boundary L point tended to zero at ∼101 K, thus showing the paraelastic to ferroelastic transition in this cyanospinel is a soft-mode transition. (author)

  3. GTLine – Gasoline as a potential CN suppressant for GTL

    KAUST Repository

    Reijnders, Jos; Boot, Michael; Johansson, Bengt; de Goey, Philip

    2018-01-01

    The main driver to investigate low temperature combustion concepts, such as partially premixed combustion (PPC), is the promise of low particulate matter (PM) and nitric oxide (NOx) emissions. A critical prerequisite for PPC is to temporally isolate the fuel injection and combustion events. In practice, exhaust gas recirculation (EGR) is applied in order to sufficiently extend the ignition delay to that effect. Hereby, in general, higher EGR rates are necessary for fuels with higher cetane numbers (CN). Against this background, the objective of this paper is to investigate the efficacy, with respect to PM-NOx emissions and engine efficiency, of gasoline as a potential gas-to-liquid (GTL) CN suppressant in various dosages. The performance of the resulting GTLine blend will be evaluated under PPC operating conditions in a heavy-duty direct-injected diesel engine. Setting aside for a moment any potential practical issues (e.g., flash point, vapor pressure) that fall outside the scope of this study, our data suggest that blending gasoline to otherwise high CN GTL appears to be a promising route to improve not only the efficiency, but also PM and NOx emissions, particularly when operating in PPC mode. Interestingly, this benefit is notwithstanding the high aromaticity of the gasoline compared to GTL. Given the ongoing dieselization trend and associated surplus of gasoline in many regions, notably Europe, along with the fact that the cost price of gasoline is significantly lower than that of GTL, the proposed GTLine approach promises to be a cost effective way to accommodate GTL in a world wherein low temperature combustion concepts, such as PPC, appear to be really taking off.

  4. GTLine – Gasoline as a potential CN suppressant for GTL

    KAUST Repository

    Reijnders, Jos

    2018-03-23

    The main driver to investigate low temperature combustion concepts, such as partially premixed combustion (PPC), is the promise of low particulate matter (PM) and nitric oxide (NOx) emissions. A critical prerequisite for PPC is to temporally isolate the fuel injection and combustion events. In practice, exhaust gas recirculation (EGR) is applied in order to sufficiently extend the ignition delay to that effect. Hereby, in general, higher EGR rates are necessary for fuels with higher cetane numbers (CN). Against this background, the objective of this paper is to investigate the efficacy, with respect to PM-NOx emissions and engine efficiency, of gasoline as a potential gas-to-liquid (GTL) CN suppressant in various dosages. The performance of the resulting GTLine blend will be evaluated under PPC operating conditions in a heavy-duty direct-injected diesel engine. Setting aside for a moment any potential practical issues (e.g., flash point, vapor pressure) that fall outside the scope of this study, our data suggest that blending gasoline to otherwise high CN GTL appears to be a promising route to improve not only the efficiency, but also PM and NOx emissions, particularly when operating in PPC mode. Interestingly, this benefit is notwithstanding the high aromaticity of the gasoline compared to GTL. Given the ongoing dieselization trend and associated surplus of gasoline in many regions, notably Europe, along with the fact that the cost price of gasoline is significantly lower than that of GTL, the proposed GTLine approach promises to be a cost effective way to accommodate GTL in a world wherein low temperature combustion concepts, such as PPC, appear to be really taking off.

  5. The new carbodiimide Li_2Gd_2Sr(CN_2)_5 having a crystal structure related to that of Gd_2(CN_2)_3

    International Nuclear Information System (INIS)

    Unverfehrt, Leonid; Stroebele, Markus; Meyer, H. Juergen

    2013-01-01

    The new carbodiimide compounds Li_2RE_2Sr(CN_2)_5 (RE = Sm, Gd, Eu, Tb) were prepared by a straight forward solid state metathesis reaction of REF_3, SrF_2, and Li_2(CN_2) at around 600 C. The crystal structure of Li_2Gd_2Sr(CN_2)_5 was solved based on X-ray single-crystal diffraction data. Corresponding Li_2RE_2Sr(CN_2)_5 compounds were analyzed by isotypic indexing of their powder patterns. The crystal structure of Li_2Gd_2Sr(CN_2)_5 can be well related to that of Gd_2(CN_2)_3, because both structures are based on layered structures composed of close packed layers of [N=C=N]"2"- sticks, alternating with layers of metal ions. The crystal structure of Li_2Gd_2Sr(CN_2)_5 can be considered to contain an ABC layer sequence of [N = C=N]"2"- layers with the interlayer voids being occupied by (three) distinct types of cations. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Lithium dynamics in carbon-rich polymer-derived SiCN ceramics probed by nuclear magnetic resonance

    Science.gov (United States)

    Baek, Seung-Ho; Reinold, Lukas Mirko; Graczyk-Zajac, Magdalena; Riedel, Ralf; Hammerath, Franziska; Büchner, Bernd; Grafe, Hans-Joachim

    2014-05-01

    We report 7Li, 29Si, and 13C NMR studies of two different carbon-rich SiCN ceramics SiCN-1 and SiCN-3 derived from the preceramic polymers polyphenylvinylsilylcarbodiimide and polyphenylvinylsilazane, respectively. From the spectral analysis of the three nuclei, we find that only the 13C spectrum is strongly influenced by Li insertion/extraction, suggesting that carbon phases are the major electrochemically active sites for Li storage. Temperature (T) and Larmor frequency (ωL) dependences of the 7Li linewidth and spin-lattice relaxation rates T1-1 are described by an activated law with the activation energy EA of 0.31 eV and the correlation time τ0 in the high temperature limit of 1.3 ps. The 3 / 2 power law dependence of T1-1 on ωL which deviates from the standard Bloembergen, Purcell, and Pound (BPP) model implies that the Li motion on the μs timescale is governed by continuum diffusion mechanism rather than jump diffusion. On the other hand, the rotating frame relaxation rate T1ρ-1 results suggest that the slow motion of Li on the ms timescale may be affected by complex diffusion and/or non-diffusion processes.

  7. Valence shell threshold photoelectron spectroscopy of the CHxCN (x = 0-2) and CNC radicals.

    Science.gov (United States)

    Garcia, Gustavo A; Krüger, Julia; Gans, Bérenger; Falvo, Cyril; Coudert, Laurent H; Loison, Jean-Christophe

    2017-07-07

    We present the photoelectron spectroscopy of four radical species, CH x CN (x = 0-2) and CNC, formed in a microwave discharge flow-tube reactor by consecutive H abstractions from CH 3 CN (CH x CN + F → CH x-1 CN + HF (x = 1-3)). The spectra were obtained combining tunable vacuum ultraviolet synchrotron radiation with double imaging electron/ion coincidence techniques, which yielded mass-selected threshold photoelectron spectra. The results obtained for H 2 CCN complement existing ones while for the other radicals the data represent the first observation of their (single-photon) ionizing transitions. In the case of H 2 CCN, Franck-Condon calculations have been performed in order to assign the vibrational structure of the X + 1 A 1 ←X 2 B 1 ionizing transition. A similar treatment for the HCCN, CCN, and CNC radicals appeared to be more complicated mainly because a Renner-Teller effect strongly affects the vibrational levels of the ground electronic state of the HCCN + , CCN, and CNC species. Nevertheless, the first adiabatic ionization energies of these radicals are reported and compared to our ab initio calculated values, leading to new values for enthalpies of formation (Δ f H 298 0 (HCCN + (X 2 A ' ))=1517±12kJmol -1 ,Δ f H 298 0 (CCN(X 2 Π))=682±13kJmol -1 , and Δ f H 298 0 (CNC(X 2 Πg))=676±12kJmol -1 ), which are of fundamental importance for astrochemistry.

  8. The chemical composition and band gap of amorphous Si:C:N:H layers

    Energy Technology Data Exchange (ETDEWEB)

    Swatowska, Barbara, E-mail: swatow@agh.edu.pl [AGH University of Science and Technology, Department of Electronics, Mickiewicza Av. 30, 30-059 Krakow (Poland); Kluska, Stanislawa; Jurzecka-Szymacha, Maria [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Mickiewicza Av. 30, 30-059 Krakow (Poland); Stapinski, Tomasz [AGH University of Science and Technology, Department of Electronics, Mickiewicza Av. 30, 30-059 Krakow (Poland); Tkacz-Smiech, Katarzyna [AGH University of Science and Technology, Faculty of Materials Science and Ceramics, Mickiewicza Av. 30, 30-059 Krakow (Poland)

    2016-05-15

    Highlights: • Six type of amorphous hydrogenated films were obtained and analysed. • Investigated chemical bondings strongly influenced energy gap values. • Analysed layers could be applied as semiconductors and also as dielectrics. - Abstract: In this work we presented the correlation between the chemical composition of amorphous Si:C:N:H layers of various content of silicon, carbon and nitrogen, and their band gap. The series of amorphous Si:C:N:H layers were obtained by plasma assisted chemical vapour deposition method in which plasma was generated by RF (13.56 MHz, 300 W) and MW (2.45 GHz, 2 kW) onto monocrystalline silicon Si(001) and borosilicate glass. Structural studies were based on FTIR transmission spectrum registered within wavenumbers 400–4000 cm{sup −1}. The presence of Si−C, Si−N, C−N, C=N, C=C, C≡N, Si−H and C−H bonds was shown. The values band gap of the layers have been determined from spectrophotometric and ellipsometric measurements. The respective values are contained in the range between 1.64 eV – characteristic for typical semiconductor and 4.21 eV – for good dielectric, depending on the chemical composition and atomic structure of the layers.

  9. Tree species is the major factor explaining C:N ratios in European forest soils

    DEFF Research Database (Denmark)

    Cools, Nathalie; Vesterdal, Lars; De Vos, Bruno

    2014-01-01

    The C:N ratio is considered as an indicator of nitrate leaching in response to high atmospheric nitrogen (N) deposition. However, the C:N ratio is influenced by a multitude of other site-related factors. This study aimed to unravel the factors determining C:N ratios of forest floor, mineral soil...... mineral soil layers it was the humus type. Deposition and climatic variables were of minor importance at the European scale. Further analysis for eight main forest tree species individually, showed that the influence of environmental variables on C:N ratios was tree species dependent. For Aleppo pine...... and peat top soils in more than 4000 plots of the ICP Forests large-scale monitoring network. The first objective was to quantify forest floor, mineral and peat soil C:N ratios across European forests. Secondly we determined the main factors explaining this C:N ratio using a boosted regression tree...

  10. Estimation of CN Parameter for Small Agricultural Watersheds Using Asymptotic Functions

    OpenAIRE

    Tomasz Kowalik; Andrzej Walega

    2015-01-01

    This paper investigates a possibility of using asymptotic functions to determine the value of curve number (CN) parameter as a function of rainfall in small agricultural watersheds. It also compares the actually calculated CN with its values provided in the Soil Conservation Service (SCS) National Engineering Handbook Section 4: Hydrology (NEH-4) and Technical Release 20 (TR-20). The analysis showed that empirical CN values presented in the National Engineering Handbook tables differed from t...

  11. Regional Calibration of SCS-CN L-THIA Model: Application for Ungauged Basins

    OpenAIRE

    Jeon, Ji-Hong; Lim, Kyoung; Engel, Bernard

    2014-01-01

    Estimating surface runoff for ungauged watershed is an important issue. The Soil Conservation Service Curve Number (SCS-CN) method developed from long-term experimental data is widely used to estimate surface runoff from gaged or ungauged watersheds. Many modelers have used the documented SCS-CN parameters without calibration, sometimes resulting in significant errors in estimating surface runoff. Several methods for regionalization of SCS-CN parameters were evaluated. The regionalization met...

  12. Humic acid batteries derived from vermicomposts at different C/N ratios

    Science.gov (United States)

    Shamsuddin, R. M.; Borhan, A.; Lim, W. K.

    2017-06-01

    Humic acid is a known fertilizer derived from decomposed organic matters. Organic wastes are normally landfilled for disposal which had contributed negatively to the environment. From waste-to-wealth perspective, such wastes are potential precursors for compost fertilizers. When worms are added into a composting process, the process is termed as vermicomposting. In this work, humic acid from vermicompost derived from campus green wastes was developed into a battery. This adds value proposition to compost instead of being traditionally used solely as soil improver. This research work aimed to study the correlation between electrical potential generated by humic acid at different Carbon to Nitrogen (C/N) ratios of vermicompost at 20, 25, 30 and 35. The temperature and pH profiles of composting revealed that the compost was ready after 55 days. The humic acid was extracted from compost via alkaline extraction followed by precipitation in a strong acid. The extracted humic acid together with other additives were packed into a compartment and termed as vermibattery. Another set of battery running only on the additives was also prepared as a control. The net voltage produced by a single vermibattery cell with Zn and PbO electrodes was in the range of 0.31 to 0.44 V with compost at C/N ratio of 30 gave the highest voltage. The battery can be connected in series to increase the voltage generation. Quality assessment on the compost revealed that the final carbon content is between 16 to 23 wt%, nitrogen content of 0.4 to 0.5 wt%, humic acid yield of 0.7 to 1.5 wt% and final compost mass reduction of 10 to 35 wt%. Composting campus green wastes carries multi-fold benefits of reducing labour requirement, generating fertilizer for campus greenery and green battery construction.

  13. A sediment graph model based on SCS-CN method

    Science.gov (United States)

    Singh, P. K.; Bhunya, P. K.; Mishra, S. K.; Chaube, U. C.

    2008-01-01

    SummaryThis paper proposes new conceptual sediment graph models based on coupling of popular and extensively used methods, viz., Nash model based instantaneous unit sediment graph (IUSG), soil conservation service curve number (SCS-CN) method, and Power law. These models vary in their complexity and this paper tests their performance using data of the Nagwan watershed (area = 92.46 km 2) (India). The sensitivity of total sediment yield and peak sediment flow rate computations to model parameterisation is analysed. The exponent of the Power law, β, is more sensitive than other model parameters. The models are found to have substantial potential for computing sediment graphs (temporal sediment flow rate distribution) as well as total sediment yield.

  14. ESR studies of electron irradiated K3Ir(CN)6 in KCl single crystals

    International Nuclear Information System (INIS)

    Vugman, N.V.; Pinhal, N.M.

    1983-01-01

    ESR studies of KCl single crystals doped with small amounts of K 3 Ir(CN) 6 and submitted to a prolongued 2 MeV electron irradiation at room temperature reveal the presence of the [IR(CN) 5 Cl] 4- and [Ir(CN) 4 Cl 2 ] 4- new molecular species. Ligand spin densities and ligand field parameters are calculated from the experimental hyperfine and superhyperfine interactions and compared to previous data on the [Ir(CN) 5 ] 4- species. (Author) [pt

  15. THE SPATIAL DISTRIBUTION OF OH AND CN RADICALS IN THE COMA OF COMET ENCKE

    International Nuclear Information System (INIS)

    Ihalawela, Chandrasiri A.; Pierce, Donna M.; Dorman, Garrett R.; Cochran, Anita L.

    2011-01-01

    Multiple potential parent species have been proposed to explain CN abundances in comet comae, but the parent has not been definitively identified for all comets. This study examines the spatial distribution of CN radicals in the coma of comet Encke and determines the likelihood that CN is a photodissociative daughter of HCN in the coma. Comet Encke is the shortest orbital period (3.3 years) comet known and also has a low dust-to-gas ratio based on optical observations. Observations of CN were obtained from 2003 October 22 to 24, using the 2.7 m telescope at McDonald Observatory. To determine the parent of CN, the classical vectorial model was modified by using a cone shape in order to reproduce Encke's highly aspherical and asymmetric coma. To test the robustness of the modified model, the spatial distribution of OH was also modeled. This also allowed us to obtain CN/OH ratios in the coma. Overall, we find the CN/OH ratio to be 0.009 ± 0.004. The results are consistent with HCN being the photodissociative parent of CN, but we cannot completely rule out other possible parents such as CH 3 CN and HC 3 N. We also found that the fan-like feature spans ∼90°, consistent with the results of Woodney et al..

  16. Band structure of semiconductors

    CERN Document Server

    Tsidilkovski, I M

    2013-01-01

    Band Structure of Semiconductors provides a review of the theoretical and experimental methods of investigating band structure and an analysis of the results of the developments in this field. The book presents the problems, methods, and applications in the study of band structure. Topics on the computational methods of band structure; band structures of important semiconducting materials; behavior of an electron in a perturbed periodic field; effective masses and g-factors for the most commonly encountered band structures; and the treatment of cyclotron resonance, Shubnikov-de Haas oscillatio

  17. The dynamics of a shear band

    Science.gov (United States)

    Giarola, Diana; Capuani, Domenico; Bigoni, Davide

    2018-03-01

    A shear band of finite length, formed inside a ductile material at a certain stage of a continued homogeneous strain, provides a dynamic perturbation to an incident wave field, which strongly influences the dynamics of the material and affects its path to failure. The investigation of this perturbation is presented for a ductile metal, with reference to the incremental mechanics of a material obeying the J2-deformation theory of plasticity (a special form of prestressed, elastic, anisotropic, and incompressible solid). The treatment originates from the derivation of integral representations relating the incremental mechanical fields at every point of the medium to the incremental displacement jump across the shear band faces, generated by an impinging wave. The boundary integral equations (under the plane strain assumption) are numerically approached through a collocation technique, which keeps into account the singularity at the shear band tips and permits the analysis of an incident wave impinging a shear band. It is shown that the presence of the shear band induces a resonance, visible in the incremental displacement field and in the stress intensity factor at the shear band tips, which promotes shear band growth. Moreover, the waves scattered by the shear band are shown to generate a fine texture of vibrations, parallel to the shear band line and propagating at a long distance from it, but leaving a sort of conical shadow zone, which emanates from the tips of the shear band.

  18. Review IPEEE C.N. external event Vandellos II; Revision del IPEEE de otros sucesos externos de C.N. Vandellos II

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez, H.; Gasca, C.; Beltran, F.; Salvat, M.; Pifarre, D.; Canadell, F.; Aleman, A.

    2010-07-01

    Within the process of maintaining and updating the risk analysis of CN Vandellos II, results from the review of the study of vulnerability of the plant against severe accidents caused by external events (Individual Plant Examination on Extornal Events, IPEEE).

  19. Characterization by FTIR and nuclear analytical techniques of CN{sub x} films elaborated by laser ablation; Caracterizacion por FTIR y tecnicas analiticas nucleares de peliculas de CN{sub x} elaboradas por ablacion laser

    Energy Technology Data Exchange (ETDEWEB)

    Olea M, O.F

    2003-07-01

    At the present time the technique of deposit of laser ablation is used to produce different types of thin films. At the moment in the National Institute of Nuclear Research (ININ) it is carried out an investigation on the thermoluminescent response of thin films of CN{sub x} with possible application in dosimetry of electromagnetic radiation. Under this context, the present work is part of this investigation and has as objective to characterize thin films of CN{sub x} by means of Infrared spectrometry and nuclear analytical techniques. The deposits were elaborated by laser ablation under different such experimental conditions as: pressure of Nitrogen in the system (3 x 10{sup -3} and 7.5 X 10{sup -2} Torr), Distance target-substrate (3 and 5 cm) and density of incident energy in the target (from 17.5 up to 23.8 J/cm{sup 2}). Graphite of high purity was used like target and the deposits were made on their substrates of intrinsic silicon (100). By means of infrared spectrometry by Fourier Transform (Ftir) the type of bonds which are in the structure of the films of CN{sub x} were determined. The spectra of this type of samples present in general four characteristic bands related with different types of bonds among the elements C, O, H, N such as: C-C, C-N, C-H, N-H, O-H, C=N, C{identical_to}N, among others. It was carried out a semi quantitative study of the samples isolating each band of the total infrared spectra and making a comparison between their intensities and forms. This study allowed to observe that there is a dependence of the structure of the films with regard to the time, since mainly bonds of the type Sp{sup 3} between Hydrogen and Carbon (C-H) they presented a remarkable variation in intensity, increasing as it lapsed the time until reaching to a stabilization where the bonds already not varying. This increase probably is due to the absorption of water of the atmosphere, although one has seen in the literature that the incorporation of this compound in

  20. cn.FARMS: a latent variable model to detect copy number variations in microarray data with a low false discovery rate.

    Science.gov (United States)

    Clevert, Djork-Arné; Mitterecker, Andreas; Mayr, Andreas; Klambauer, Günter; Tuefferd, Marianne; De Bondt, An; Talloen, Willem; Göhlmann, Hinrich; Hochreiter, Sepp

    2011-07-01

    Cost-effective oligonucleotide genotyping arrays like the Affymetrix SNP 6.0 are still the predominant technique to measure DNA copy number variations (CNVs). However, CNV detection methods for microarrays overestimate both the number and the size of CNV regions and, consequently, suffer from a high false discovery rate (FDR). A high FDR means that many CNVs are wrongly detected and therefore not associated with a disease in a clinical study, though correction for multiple testing takes them into account and thereby decreases the study's discovery power. For controlling the FDR, we propose a probabilistic latent variable model, 'cn.FARMS', which is optimized by a Bayesian maximum a posteriori approach. cn.FARMS controls the FDR through the information gain of the posterior over the prior. The prior represents the null hypothesis of copy number 2 for all samples from which the posterior can only deviate by strong and consistent signals in the data. On HapMap data, cn.FARMS clearly outperformed the two most prevalent methods with respect to sensitivity and FDR. The software cn.FARMS is publicly available as a R package at http://www.bioinf.jku.at/software/cnfarms/cnfarms.html.

  1. Plasmon band gap generated by intense ion acoustic waves

    International Nuclear Information System (INIS)

    Son, S.; Ku, S.

    2010-01-01

    In the presence of an intense ion acoustic wave, the energy-momentum dispersion relation of plasmons is strongly modified to exhibit a band gap structure. The intensity of an ion acoustic wave might be measured from the band gap width. The plasmon band gap can be used to block the nonlinear cascading channel of the Langmuir wave decay.

  2. The cyanogen band of Comet Halley

    Science.gov (United States)

    Tatum, J. B.; Campbell, E. C.

    The results of improved whole disk solar irradiance spectrum calculations performed for projected Halley's Comet heliocentric radial velocity and distance are provided. The computations were carried out to account for Doppler effects in the Fraunhofer lines of rotational excitation bands of violet CN emissions from the comet in its encounters with solar radiation. The calculations spanned every half-day for 200 days before and after perihelion. The 801 computer images of the expected intensities were photographed in sequence to form an animated film paced by background music from Liszt's Second Hungarian Rhapsody. The results are intended for accounting for spectral changes observed due to Doppler effects induced by changing velocity and distance, rather than physical mechanisms of the emitting processes.

  3. Iodine capture by Hofmann-type clathrate Ni(II)(pz)[Ni(II)(CN)_4

    International Nuclear Information System (INIS)

    Massasso, Giovanni; Long, Jerome; Haines, Julien; Devautour-Vinot, Sabine; Maurin, Guillaume; Larionova, Joulia; Guerin, Christian; Guari, Yannick; Grandjean, Agnes; Onida, Barbara; Donnadieu, Bruno

    2014-01-01

    The thermally stable Hofmann-type clathrate framework Ni(II)(pz)[Ni(II)(CN)_4] (pz = pyrazine) was investigated for the efficient and reversible sorption of iodine (I_2) in the gaseous phase and in solution with a maximum adsorption capacity of 1 mol of I_2 per 1 mol of Ni(II)pz)[Ni(II)(CN)_4] in solution. (authors)

  4. InterProScan Result: CN211485 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available CN211485 CN211485_2_ORF1 AA5126E0BA1C15EC PRINTS PR00385 P450 3.6e-08 T IPR001128 Cytochrome P450 Molecular... Function: monooxygenase activity (GO:0004497)|Molecular Function: iron ion binding (GO:0005506)|Molecular... Function: electron carrier activity (GO:0009055)|Molecular Function: heme binding (GO:0020037) ...

  5. n-GaAs Band-Edge Repositioning by Modification with Metalloporphyrin/Polysiloxane Matrices

    Directory of Open Access Journals (Sweden)

    Hikmat S. Hilal

    2003-01-01

    system was annealed under nitrogen and used for photoelectrochemical study in water/LiCIO4/Fe(CN63-/Fe(CN64− system. The results indicated a positive shift in the value of the flat-band potential of the semiconductor due to MnP. This was manifested by shifting the values of the dark-current onset potential and the photo-current open-circuit potential towards more positive values. These findings are potentially valuable in future applications of solar energy in hydrogen and oxygen production from water.

  6. Exploring the crystallization landscape of cadmium bis(N-hydroxyethyl, N-isopropyldithiocarbamate), Cd[S{sub 2}CN(iPr)CH{sub 2}CH{sub 2}OH]{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Yee Seng; Halim, Siti Nadiah Abdul [Malaya Univ., Kuala Lumpur (Malaysia). Dept. of Chemistry; Tiekink, Edward R.T. [Malaya Univ., Kuala Lumpur (Malaysia). Dept. of Chemistry; Sunway Univ., Bandar Sunway (Malaysia). Centre for Chemical Crystallography

    2016-04-01

    Crystallization of Cd[S{sub 2}CN(iPr)CH{sub 2}CH{sub 2}OH]{sub 2} from ethanol yields the coordination polymer [{Cd[S_2CN(iPr)CH_2CH_2OH]_2}.EtOH]{sub ∞} (1) within 3 h. When the solution is allowed to stand for another hour, the needles begin to dissolve and prisms emerge of the supramolecular isomer (SI), binuclear {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2}.2EtOH (2). These have been fully characterized spectroscopically and by X-ray crystallography. Polymeric 1 has 2-fold symmetry and features dithiocarbamate ligands coordinating two octahedral Cd atoms in a μ{sub 2}κ{sup 2}-tridentate mode. Binuclear 2 is centrosymmetric with two ligands being μ{sub 2}κ{sup 2}-tridentate as for 1 but the other two being κ{sup 2}-chelating leading to square pyramidal geometries. The conversion of the kinetic crystallization product, 1, to thermodynamic 2 is irreversible but transformations mediated by recrystallization (ethanol and acetonitrile) to related literature SI species, namely coordination polymer [{Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 3}.MeCN]{sub ∞} and binuclear {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2}.2H{sub 2}O.2MeCN, are demonstrated, some of which are reversible. Three other crystallization outcomes are described whereby crystal structures were obtained for the 1:2 co-crystal {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2}:2[3-(propan-2-yl)-1,3-oxazolidine-2-thione] (3), the salt co-crystal [iPrNH{sub 2}(CH{sub 2}CH{sub 2}OH)]{sub 4}[SO{sub 4}]{sub 2}{Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2} (4) and the salt [iPrNH{sub 2}(CH{sub 2}CH{sub 2}OH)]{Cd[S_2CN(iPr)CH_2CH_2OH]_3} (5). These arise as a result of decomposition/oxidation of the dithiocarbamate ligands. In each of 3 and 4 the binuclear {Cd[S_2CN(iPr)CH_2CH_2OH]_2}{sub 2} SI, as in 2, is observed strongly suggesting a thermodynamic preference for this form.

  7. Strong field control of predissociation dynamics.

    Science.gov (United States)

    Corrales, María E; Balerdi, Garikoitz; Loriot, Vincent; de Nalda, Rebeca; Bañares, Luis

    2013-01-01

    Strong field control scenarios are investigated in the CH3I predissociation dynamics at the origin of the second absorption B-band, in which state-selective electronic predissociation occurs through the crossing with a valence dissociative state. Dynamic Stark control (DSC) and pump-dump strategies are shown capable of altering both the predissociation lifetime and the product branching ratio.

  8. Testing strong interaction theories

    International Nuclear Information System (INIS)

    Ellis, J.

    1979-01-01

    The author discusses possible tests of the current theories of the strong interaction, in particular, quantum chromodynamics. High energy e + e - interactions should provide an excellent means of studying the strong force. (W.D.L.)

  9. Analysis of the runoff generation mechanism for the investigation of the SCS-CN method applicability to a partial area experimental watershed

    Science.gov (United States)

    Soulis, K. X.; Valiantzas, J. D.; Dercas, N.; Londra, P. A.

    2009-01-01

    The Soil Conservation Service Curve Number (SCS-CN) method is widely used for predicting direct runoff volume for a given rainfall event. The applicability of the SCS-CN method and the runoff generation mechanism were thoroughly analysed in a Mediterranean experimental watershed in Greece. The region is characterized by a Mediterranean semi-arid climate. A detailed land cover and soil survey using remote sensing and GIS techniques, showed that the watershed is dominated by coarse soils with high hydraulic conductivities, whereas a smaller part is covered with medium textured soils and impervious surfaces. The analysis indicated that the SCS-CN method fails to predict runoff for the storm events studied, and that there is a strong correlation between the CN values obtained from measured runoff and the rainfall depth. The hypothesis that this correlation could be attributed to the existence of an impermeable part in a very permeable watershed was examined in depth, by developing a numerical simulation water flow model for predicting surface runoff generated from each of the three soil types of the watershed. Numerical runs were performed using the HYDRUS-1D code. The results support the validity of this hypothesis for most of the events examined where the linear runoff formula provides better results than the SCS-CN method. The runoff coefficient of this formula can be taken equal to the percentage of the impervious area. However, the linear formula should be applied with caution in case of extreme events with very high rainfall intensities. In this case, the medium textured soils may significantly contribute to the total runoff and the linear formula may significantly underestimate the runoff produced.

  10. Investigation of the direct runoff generation mechanism for the analysis of the SCS-CN method applicability to a partial area experimental watershed

    Science.gov (United States)

    Soulis, K. X.; Valiantzas, J. D.; Dercas, N.; Londra, P. A.

    2009-05-01

    The Soil Conservation Service Curve Number (SCS-CN) method is widely used for predicting direct runoff volume for a given rainfall event. The applicability of the SCS-CN method and the direct runoff generation mechanism were thoroughly analysed in a Mediterranean experimental watershed in Greece. The region is characterized by a Mediterranean semi-arid climate. A detailed land cover and soil survey using remote sensing and GIS techniques, showed that the watershed is dominated by coarse soils with high hydraulic conductivities, whereas a smaller part is covered with medium textured soils and impervious surfaces. The analysis indicated that the SCS-CN method fails to predict runoff for the storm events studied, and that there is a strong correlation between the CN values obtained from measured runoff and the rainfall depth. The hypothesis that this correlation could be attributed to the existence of an impermeable part in a very permeable watershed was examined in depth, by developing a numerical simulation water flow model for predicting surface runoff generated from each of the three soil types of the watershed. Numerical runs were performed using the HYDRUS-1D code. The results support the validity of this hypothesis for most of the events examined where the linear runoff formula provides better results than the SCS-CN method. The runoff coefficient of this formula can be taken equal to the percentage of the impervious area. However, the linear formula should be applied with caution in case of extreme events with very high rainfall intensities. In this case, the medium textured soils may significantly contribute to the total runoff and the linear formula may significantly underestimate the runoff produced.

  11. Investigation of the direct runoff generation mechanism for the analysis of the SCS-CN method applicability to a partial area experimental watershed

    Directory of Open Access Journals (Sweden)

    K. X. Soulis

    2009-05-01

    Full Text Available The Soil Conservation Service Curve Number (SCS-CN method is widely used for predicting direct runoff volume for a given rainfall event. The applicability of the SCS-CN method and the direct runoff generation mechanism were thoroughly analysed in a Mediterranean experimental watershed in Greece. The region is characterized by a Mediterranean semi-arid climate. A detailed land cover and soil survey using remote sensing and GIS techniques, showed that the watershed is dominated by coarse soils with high hydraulic conductivities, whereas a smaller part is covered with medium textured soils and impervious surfaces. The analysis indicated that the SCS-CN method fails to predict runoff for the storm events studied, and that there is a strong correlation between the CN values obtained from measured runoff and the rainfall depth. The hypothesis that this correlation could be attributed to the existence of an impermeable part in a very permeable watershed was examined in depth, by developing a numerical simulation water flow model for predicting surface runoff generated from each of the three soil types of the watershed. Numerical runs were performed using the HYDRUS-1D code. The results support the validity of this hypothesis for most of the events examined where the linear runoff formula provides better results than the SCS-CN method. The runoff coefficient of this formula can be taken equal to the percentage of the impervious area. However, the linear formula should be applied with caution in case of extreme events with very high rainfall intensities. In this case, the medium textured soils may significantly contribute to the total runoff and the linear formula may significantly underestimate the runoff produced.

  12. Ion beam analysis, corrosion resistance and nanomechanical properties of TiAlCN/CN{sub x} multilayer grown by reactive magnetron sputtering

    Energy Technology Data Exchange (ETDEWEB)

    Alemón, B.; Flores, M. [Departamento de Ingeniería de Proyectos, CUCEI, Universidad de Guadalajara, J. Guadalupe Zuno 48, Los Belenes, Zapopan, Jal. 45101 (Mexico); Canto, C. [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, Mexico, DF 04510 (Mexico); Andrade, E., E-mail: andrade@fisica.unam.mx [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, Mexico, DF 04510 (Mexico); Lucio, O.G. de [Instituto de Física, UNAM, Avenida de la Investigación S/N, Coyoacán, Mexico, DF 04510 (Mexico); Rocha, M.F. [ESIME-Z, Instituto Politécnico Nacional, ALM Zacatenco, Mexico, DF 07738 (Mexico); Broitman, E. [Thin Films Physics Division, IFM, Linköping University, SE-58183 Linköping (Sweden)

    2014-07-15

    A novel TiAlCN/CN{sub x} multilayer coating, consisting of nine TiAlCN/CN{sub x} periods with a top layer 0.5 μm of CN{sub x}, was designed to enhance the corrosion resistance of CoCrMo biomedical alloy. The multilayers were deposited by dc and RF reactive magnetron sputtering from Ti{sub 0.5}Al{sub 0.5} and C targets respectively in a N{sub 2}/Ar plasma. The corrosion resistance and mechanical properties of the multilayer coatings were analyzed and compared to CoCrMo bulk alloy. Ion beam analysis (IBA) and X-ray diffraction tests were used to measure the element composition profiles and crystalline structure of the films. Corrosion resistance was evaluated by means of potentiodynamic polarization measurements using simulated body fluid (SBF) at typical body temperature and the nanomechanical properties of the multilayer evaluated by nanoindentation tests were analyzed and compared to CoCrMo bulk alloy. It was found that the multilayer hardness and the elastic recovery are higher than the substrate of CoCrMo. Furthermore the coated substrate shows a better general corrosion resistance than that of the CoCrMo alloy alone with no observation of pitting corrosion.

  13. Preparation of mesoporous carbon nitride structure by the dealloying of Ni/a-CN nanocomposite films

    Science.gov (United States)

    Zhou, Han; Shen, Yongqing; Huang, Jie; Liao, Bin; Wu, Xianying; Zhang, Xu

    2018-05-01

    The preparation of mesoporous carbon nitride (p-CN) structure by the selective dealloying process of Ni/a-CN nanocomposite films is investigated. The composition and structure of the Ni/a-CN nanocomposite films and porous carbon nitride (p-CN) films are determined by scan electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. Phase separated structure including nickel carbide phase and the surrounding amorphous carbon nitride (a-CN) matrix are detected for the as-deposited films. Though the bulk diffusion is introduced in the film during the annealing process, the grain sizes for the post-annealed films are around 10 nm and change little comparing with the ones of the as-deposited films, which is associated with the thermostability of the CN surrounding in the film. The p-CN skeleton with its pore size around 12.5 nm is formed by etching the post-annealed films, indicative of the stability of the phase separated structure during the annealing process.

  14. Reaction of cyanide with cytochrome ba3 from Thermus thermophilus: spectroscopic characterization of the Fe(II)a3-CN.Cu(II)B-CN complex suggests four 14N atoms are coordinated to CuB.

    Science.gov (United States)

    Surerus, K K; Oertling, W A; Fan, C; Gurbiel, R J; Einarsdóttir, O; Antholine, W E; Dyer, R B; Hoffman, B M; Woodruff, W H; Fee, J A

    1992-01-01

    Cytochrome ba3 from Thermus thermophilus reacts slowly with excess HCN at pH 7.4 to create a form of the enzyme in which CuA, cytochrome b, and CuB remain oxidized, while cytochrome a3 is reduced by one electron, presumably with the formation of cyanogen. We have examined this form of the enzyme by UV-visible, resonance Raman, EPR, and electron nuclear double resonance spectroscopies in conjunction with permutations of 13C- and 15N-labeled cyanide. The results support a model in which one CN- binds through the carbon atom to ferrous a3, supporting a low-spin (S = 0) configuration on the Fe; bridging by this cyanide to the CuB is weak or absent. Four 14N atoms, presumably donated by histidine residues of the protein, provide a strong equatorial ligand field about CuB; a second CN- is coordinated through the carbon atom to CuB in an axial position. PMID:1314380

  15. ORTHO-TO-PARA ABUNDANCE RATIO (OPR) OF AMMONIA IN 15 COMETS: OPRs OF AMMONIA VERSUS 14N/15N RATIOS IN CN

    International Nuclear Information System (INIS)

    Shinnaka, Yoshiharu; Kawakita, Hideyo; Kobayashi, Hitomi; Jehin, Emmanuel; Manfroid, Jean; Hutsemekers, Damien; Arpigny, Claude

    2011-01-01

    The ortho-to-para abundance ratio (OPR) of cometary molecules is considered to be one of the primordial characteristics of cometary ices. We present OPRs of ammonia (NH 3 ) in 15 comets based on optical high-dispersion spectroscopic observations of NH 2 , which is a photodissociation product of ammonia in the gaseous coma. The observations were mainly carried out with the VLT/UVES. The OPR of ammonia is estimated from the OPR of NH 2 based on the observations of the NH 2 (0, 9, 0) vibronic band. The absorption lines by the telluric atmosphere are corrected and the cometary C 2 emission lines blended with NH 2 lines are removed in our analysis. The ammonia OPRs show a cluster between 1.1 and 1.2 (this corresponds to a nuclear spin temperature of ∼30 K) for all comets in our sample except for 73P/Schwassmann-Wachmann 3 (73P/SW3). Comet 73P/SW3 (both B- and C-fragments) shows the OPR of ammonia consistent with nuclear spin statistical weight ratio (1.0) that indicates a high-temperature limit as nuclear spin temperature. We compared the ammonia OPRs with other properties ( 14 N/ 15 N ratios in CN, D/H ratios of water, and mixing ratios of volatiles). Comet 73P/SW3 is clearly different from the other comets in the plot of ammonia OPRs versus 14 N/ 15 N ratios in CN. The ammonia OPRs of 1.0 and lower 15 N-fractionation of CN in comet 73P/SW3 imply that icy materials in this comet formed under warmer conditions than other comets. Comets may be classified into two groups in the plot of ammonia OPRs against 14 N/ 15 N ratios in CN.

  16. Transition Dipole Moments and Transition Probabilities of the CN Radical

    Science.gov (United States)

    Yin, Yuan; Shi, Deheng; Sun, Jinfeng; Zhu, Zunlue

    2018-04-01

    This paper studies the transition probabilities of electric dipole transitions between 10 low-lying states of the CN radical. These states are X2Σ+, A2Π, B2Σ+, a4Σ+, b4Π, 14Σ‑, 24Π, 14Δ, 16Σ+, and 16Π. The potential energy curves are calculated using the CASSCF method, which is followed by the icMRCI approach with the Davidson correction. The transition dipole moments between different states are calculated. To improve the accuracy of potential energy curves, core–valence correlation and scalar relativistic corrections, as well as the extrapolation of potential energies to the complete basis set limit are included. The Franck–Condon factors and Einstein coefficients of emissions are calculated. The radiative lifetimes are determined for the vibrational levels of the A2Π, B2Σ+, b4Π, 14Σ‑, 24Π, 14Δ, and 16Π states. According to the transition probabilities and radiative lifetimes, some guidelines for detecting these states spectroscopically are proposed. The spin–orbit coupling effect on the spectroscopic and vibrational properties is evaluated. The splitting energy in the A2Π state is determined to be 50.99 cm‑1, which compares well with the experimental ones. The potential energy curves, transition dipole moments, spectroscopic parameters, and transition probabilities reported in this paper can be considered to be very reliable. The results obtained here can be used as guidelines for detecting these transitions, in particular those that have not been measured in previous experiments or have not been observed in the Sun, comets, stellar atmospheres, dark interstellar clouds, and diffuse interstellar clouds.

  17. Wide Band to ''Double Band'' upgrade

    International Nuclear Information System (INIS)

    Kasper, P.; Currier, R.; Garbincius, P.; Butler, J.

    1988-06-01

    The Wide Band beam currently uses electrons obtained from secondary photon conversions to produce the photon beam incident on the experimental targets. By transporting the positrons produced in these conversions as well as the electrons it is possible to almost double the number of photons delivered to the experiments per primary beam proton. 11 figs

  18. A syntactical comparison between pair sentential calculus PSC and Gupta's definitional calculus Cn

    OpenAIRE

    石井,忠夫

    2016-01-01

    In this paper we will compare two logical systems PSC and Cn with a syntactical point of view. Because both notions of the pair-sentence with stage number in PSC and Gupta's sentence-definition with revision stage number in Cn are very similar, and both can deal with paradoxical sentences like a simple Liar sentence. His system was defined as a predicate calculus, but here we will introduce the propositional version of Cn for the comparison, and we had the following results: (1) C0 is a sublo...

  19. Optical model with multiple band couplings using soft rotator structure

    Science.gov (United States)

    Martyanov, Dmitry; Soukhovitskii, Efrem; Capote, Roberto; Quesada, Jose Manuel; Chiba, Satoshi

    2017-09-01

    A new dispersive coupled-channel optical model (DCCOM) is derived that describes nucleon scattering on 238U and 232Th targets using a soft-rotator-model (SRM) description of the collective levels of the target nucleus. SRM Hamiltonian parameters are adjusted to the observed collective levels of the target nucleus. SRM nuclear wave functions (mixed in K quantum number) have been used to calculate coupling matrix elements of the generalized optical model. Five rotational bands are coupled: the ground-state band, β-, γ-, non-axial- bands, and a negative parity band. Such coupling scheme includes almost all levels below 1.2 MeV of excitation energy of targets. The "effective" deformations that define inter-band couplings are derived from SRM Hamiltonian parameters. Conservation of nuclear volume is enforced by introducing a monopolar deformed potential leading to additional couplings between rotational bands. The present DCCOM describes the total cross section differences between 238U and 232Th targets within experimental uncertainty from 50 keV up to 200 MeV of neutron incident energy. SRM couplings and volume conservation allow a precise calculation of the compound-nucleus (CN) formation cross sections, which is significantly different from the one calculated with rigid-rotor potentials with any number of coupled levels.

  20. Thermoelectric band engineering: The role of carrier scattering

    Science.gov (United States)

    Witkoske, Evan; Wang, Xufeng; Lundstrom, Mark; Askarpour, Vahid; Maassen, Jesse

    2017-11-01

    Complex electronic band structures, with multiple valleys or bands at the same or similar energies, can be beneficial for thermoelectric performance, but the advantages can be offset by inter-valley and inter-band scattering. In this paper, we demonstrate how first-principles band structures coupled with recently developed techniques for rigorous simulation of electron-phonon scattering provide the capabilities to realistically assess the benefits and trade-offs associated with these materials. We illustrate the approach using n-type silicon as a model material and show that intervalley scattering is strong. This example shows that the convergence of valleys and bands can improve thermoelectric performance, but the magnitude of the improvement depends sensitively on the relative strengths of intra- and inter-valley electron scattering. Because anisotropy of the band structure also plays an important role, a measure of the benefit of band anisotropy in the presence of strong intervalley scattering is presented.

  1. Amniotic constriction bands

    Science.gov (United States)

    ... Supplements Videos & Tools Español You Are Here: Home → Medical Encyclopedia → Amniotic band sequence URL of this page: //medlineplus.gov/ency/ ... birth. The baby should be delivered in a medical center that has specialists experienced in caring for babies ... or partial loss of function of a body part. Congenital bands affecting large parts of the body cause the ...

  2. Abortion: Strong's counterexamples fail

    DEFF Research Database (Denmark)

    Di Nucci, Ezio

    2009-01-01

    This paper shows that the counterexamples proposed by Strong in 2008 in the Journal of Medical Ethics to Marquis's argument against abortion fail. Strong's basic idea is that there are cases--for example, terminally ill patients--where killing an adult human being is prima facie seriously morally...

  3. Strong Langmuir turbulence

    International Nuclear Information System (INIS)

    Goldman, M.V.

    1984-01-01

    After a brief discussion of beam-excited Langmuir turbulence in the solar wind, we explain the criteria for wave-particle, three-wave and strong turbulence interactions. We then present the results of a numerical integration of the Zakharov equations, which describe the strong turbulence saturation of a weak (low-density) high energy, bump-on-tail beam instability. (author)

  4. Strong anisotropy in the low temperature Compton profiles of ...

    Indian Academy of Sciences (India)

    able for comparison with theory, the resistivity data in α-Ga at low temperature strongly support this anisotropic ... renormalized free-atom (RFA) model [3], band model [5–7] and quantum Monte Carlo ... probability distribution function.

  5. Engine Performance Test of the 1975 Chrysler - Nissan Model CN633 Diesel Engine

    Science.gov (United States)

    1975-09-01

    An engine test of the Chrysler-Nissan Model CN633 diesel engine was performed to determine its steady-state fuel consumption and emissions (HC, CO, NOx) maps. The data acquired are summarized in this report.

  6. [Hydrogen production and enzyme activity of acidophilic strain X-29 at different C/N ratio].

    Science.gov (United States)

    Li, Qiu-bo; Xing, De-feng; Ren, Nan-qi; Zhao, Li-hua; Song, Ye-ying

    2006-04-01

    Some fermentative bacteria can produce hydrogen by utilizing carbohydrate and other kinds of organic compounds as substrates. Hydrogen production was also determined by both the limiting of growth and related enzyme activity in energy metabolism. Carbon and nitrogen are needed for the growth and metabolism of microorganisms. In addition, the carbon/nitrogen (C/N) ratio can influence the material metabolized and the energy produced. In order to improve the hydrogen production efficiency of the bacteria, we analyzed the effect of different C/N ratios on hydrogen production and the related enzyme activities in the acidophilic strain X-29 using batch test. The results indicate that the differences in the metabolism level and enzyme activity are obvious at different C/N ratios. Although the difference in liquid fermentative products produced per unit of biomass is not obvious, hydrogen production is enhanced at a specifically determined ratio. At a C/N ratio of 14 the accumulative hydrogen yield of strain X-29 reaches the maximum, 2210.9 mL/g. At different C/N ratios, the expression of hydrogenase activity vary; the activity of hydrogenase decrease quickly after reaching a maximum along with the fermentation process, but the time of expression is short. The activity of alcohol dehydrogenase (ADH) tend to stabilize after reaching a peak along with the fermentation process, the difference in expression activity is little, and the expression period is long at different C/N ratios. At a C/N ratio of 14 hydrogenase and ADH reach the maximum 2.88 micromol x (min x mg)(-1) and 33.2 micromol x (min x mg)(-1), respectively. It is shown that the C/N ratio has an important effect on enhancing hydrogen production and enzyme activity.

  7. Analysis of the Runoff for Watershed Using SCS-CN Method and Geographic Information Systems

    OpenAIRE

    P.Sundar Kumar; Dr.M.J.Ratna Kanth Babu,; Dr. T.V.Praveen; Venkata kumar.vagolu

    2010-01-01

    The Soil Conservation Service Curve Number (SCS-CN) method is widely used for predicting direct runoff volume for a given rainfall event. The applicability of the SCS-CN method and the runoff generation mechanism were thoroughly analyzed in a Mediterranean experimental watershed in Hyderabad. The region is characterized by a Mediterranean semi-arid climate. A detailed land cover and soil survey using remote sensing and GIS techniques, showed that the watershed is dominated by coarse soils wit...

  8. Application of GIS-based SCS-CN method in West Bank catchments, Palestine

    OpenAIRE

    Sameer Shadeed; Mohammad Almasri

    2010-01-01

    Among the most basic challenges of hydrology are the prediction and quantification of catchment surface runoff. The runoff curve number (CN) is a key factor in determining runoff in the SCS (Soil Conservation Service) based hydrologic modeling method. The traditional SCS-CN method for calculating the composite curve number is very tedious and consumes a major portion of the hydrologic modeling time. Therefore, geographic information systems (GIS) are now being used in combination with the SCS...

  9. Routine production of H11CN and :11C:-1-aminocyclopentanecarboxylic acid

    International Nuclear Information System (INIS)

    Sambre, J.; Vandecasteele, C.; Geothals, P.; Rabi, N.A.; Haver, D. van; Slegers, G.

    1985-01-01

    The production of H 11 CN using the 14 N(p,α) 11 C reaction, was studied. The yield is 140 mCi/μA at saturation (EOB). From 1.8 Ci of H 11 CN 140 mCi of [ 11 C]ACPC are produced routinely and under remote-control. Chemical and pharmaceutical controls showed that the product is suitable for injection. (author)

  10. First detection of cyanamide (NH2CN) towards solar-type protostars

    Science.gov (United States)

    Coutens, A.; Willis, E. R.; Garrod, R. T.; Müller, H. S. P.; Bourke, T. L.; Calcutt, H.; Drozdovskaya, M. N.; Jørgensen, J. K.; Ligterink, N. F. W.; Persson, M. V.; Stéphan, G.; van der Wiel, M. H. D.; van Dishoeck, E. F.; Wampfler, S. F.

    2018-05-01

    Searches for the prebiotically relevant cyanamide (NH2CN) towards solar-type protostars have not been reported in the literature. We present here the first detection of this species in the warm gas surrounding two solar-type protostars, using data from the Atacama Large Millimeter/Submillimeter Array Protostellar Interferometric Line Survey (PILS) of IRAS 16293-2422 B and observations from the IRAM Plateau de Bure Interferometer of NGC 1333 IRAS2A. We also detected the deuterated and 13C isotopologs of NH2CN towards IRAS 16293-2422 B. This is the first detection of NHDCN in the interstellar medium. Based on a local thermodynamic equilibrium analysis, we find that the deuteration of cyanamide ( 1.7%) is similar to that of formamide (NH2CHO), which may suggest that these two molecules share NH2 as a common precursor. The NH2CN/NH2CHO abundance ratio is about 0.2 for IRAS 16293-2422 B and 0.02 for IRAS2A, which is comparable to the range of values found for Sgr B2. We explored the possible formation of NH2CN on grains through the NH2 + CN reaction using the chemical model MAGICKAL. Grain-surface chemistry appears capable of reproducing the gas-phase abundance of NH2CN with the correct choice of physical parameters.

  11. New approach to neurorehabilitation: cranial nerve noninvasive neuromodulation (CN-NINM) technology

    Science.gov (United States)

    Danilov, Yuri P.; Tyler, Mitchel E.; Kaczmarek, Kurt A.; Skinner, Kimberley L.

    2014-06-01

    Cranial Nerve NonInvasive NeuroModulation (CN-NINM) is a primary and complementary multi-targeted rehabilitation therapy that appears to initiate the recovery of multiple damaged or suppressed brain functions affected by neurological disorders. It is deployable as a simple, home-based device (portable neuromodulation stimulator, or PoNSTM) and training regimen following initial patient training in an outpatient clinic. It may be easily combined with many existing rehabilitation therapies, and may reduce or eliminate the need for more aggressive invasive procedures or possibly decrease total medication intake. CN-NINM uses sequenced patterns of electrical stimulation on the tongue. Our hypothesis is that CN-NINM induces neuroplasticity by noninvasive stimulation of two major cranial nerves: trigeminal (CN-V), and facial (CN-VII). This stimulation excites a natural flow of neural impulses to the brainstem (pons varolli and medulla), and cerebellum, to effect changes in the function of these targeted brain structures, extending to corresponding nuclei of the brainstem. CN-NINM represents a synthesis of a new noninvasive brain stimulation technique with applications in physical medicine, cognitive, and affective neurosciences. Our new stimulation method appears promising for treatment of a full spectrum of movement disorders, and for both attention and memory dysfunction associated with traumatic brain injury.

  12. Soil microbial C:N ratio is a robust indicator of soil productivity for paddy fields

    Science.gov (United States)

    Li, Yong; Wu, Jinshui; Shen, Jianlin; Liu, Shoulong; Wang, Cong; Chen, Dan; Huang, Tieping; Zhang, Jiabao

    2016-10-01

    Maintaining good soil productivity in rice paddies is important for global food security. Numerous methods have been developed to evaluate paddy soil productivity (PSP), most based on soil physiochemical properties and relatively few on biological indices. Here, we used a long-term dataset from experiments on paddy fields at eight county sites and a short-term dataset from a single field experiment in southern China, and aimed at quantifying relationships between PSP and the ratios of carbon (C) to nutrients (N and P) in soil microbial biomass (SMB). In the long-term dataset, SMB variables generally showed stronger correlations with the relative PSP (rPSP) compared to soil chemical properties. Both correlation and variation partitioning analyses suggested that SMB N, P and C:N ratio were good predictors of rPSP. In the short-term dataset, we found a significant, negative correlation of annual rice yield with SMB C:N (r = -0.99), confirming SMB C:N as a robust indicator for PSP. In treatments of the short-term experiment, soil amendment with biochar lowered SMB C:N and improved PSP, while incorporation of rice straw increased SMB C:N and reduced PSP. We conclude that SMB C:N ratio does not only indicate PSP but also helps to identify management practices that improve PSP.

  13. Structure and bonding of ScCN and ScNC: Ground and low-lying states

    International Nuclear Information System (INIS)

    Kalemos, Apostolos; Metropoulos, Aristophanes; Mavridis, Aristides

    2012-01-01

    Graphical abstract: The experimentally unknown systems ScCN and ScNC have been studied through single reference CISD and CCSD(T) methods. A total of 20 = 10 (ScCN) + 10 (ScNC) states were examined. All states are quite ionic whereas ScNC(X ∼3 Δ) is stabler than ScCN(X ∼3 Δ) by ∼5 kcal/mol. Display Omitted Highlights: ► We have studied through ab initio methods the polytopic system Sc[CN]. ► A series of low lying states for both isomeric forms have been examined. ► Around equilibrium the system displays a pronounced Sc + [CN] − ionic character. - Abstract: We have studied the experimentally unknown Sc[CN] molecular system in both its isomeric forms, scandium cyanide (ScCN) and isocyanide (ScNC), through ab initio computations. We report energetics, geometries, harmonic frequencies, and dipole moments for the first 20 Sc[CN] states correlating diabatically to Sc + ( 3 D, 1 D, 3 F) + CN − (X 1 Σ + ). Both isomers have a pronounced ionic character around equilibrium due to the high electron affinity of the CN group and the low ionization energy of the Sc atom. According to our calculations the ScNC isomer (X ∼3 Δ) is stabler than the ScCN(X ∼3 Δ) by ∼5 kcal/mol.

  14. Study on re-sputtering during CN{sub x} film deposition through spectroscopic diagnostics of plasma

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Peipei; Yang, Xu; Li, Hui; Cai, Hua [Department of Optical Science and Engineering, Fudan University, Shanghai 200433 (China); Sun, Jian; Xu, Ning [Department of Optical Science and Engineering, Fudan University, Shanghai 200433 (China); Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, Fudan University, Shanghai 200433 (China); Wu, Jiada, E-mail: jdwu@fudan.edu.cn [Department of Optical Science and Engineering, Fudan University, Shanghai 200433 (China); Shanghai Engineering Research Center of Ultra-Precision Optical Manufacturing, Fudan University, Shanghai 200433 (China); Engineering Research Center of Advanced Lighting Technology, Ministry of Education, Fudan University, Shanghai 200433 (China)

    2015-10-15

    A nitrogen-carbon plasma was generated during the deposition of carbon nitride (CN{sub x}) thin films by pulsed laser ablation of a graphite target in a discharge nitrogen plasma, and the optical emission of the generated nitrogen-carbon plasma was measured for the diagnostics of the plasma and the characterization of the process of CN{sub x} film deposition. The nitrogen-carbon plasma was recognized to contain various species including nitrogen molecules and molecular ions excited in the ambient N{sub 2} gas, carbon atoms and atomic ions ablated from the graphite target and CN radicals. The temporal evolution and spatial distribution of the CN emission and their dependence on the substrate bias voltage show two groups of CN radicals flying in opposite directions. One represents the CN radicals formed as the products of the reactions occurring in the nitrogen-carbon plasma, revealing the reactive deposition of CN{sub x} film due to the reactive expansion of the ablation carbon plasma in the discharge nitrogen plasma and the effective formation of gaseous CN radicals as precursors for CN{sub x} film growth. The other one represents the CN radicals re-sputtered from the growing CN{sub x} film by energetic plasma species, evidencing the re-sputtering of the growing film accompanying film growth. And, the re-sputtering presents ion-induced sputtering features.

  15. Strong intrinsic motivation

    OpenAIRE

    Dessi, Roberta; Rustichini, Aldo

    2015-01-01

    A large literature in psychology, and more recently in economics, has argued that monetary rewards can reduce intrinsic motivation. We investigate whether the negative impact persists when intrinsic motivation is strong, and test this hypothesis experimentally focusing on the motivation to undertake interesting and challenging tasks, informative about individual ability. We find that this type of task can generate strong intrinsic motivation, that is impervious to the effect of monetary incen...

  16. Bitcoin Meets Strong Consistency

    OpenAIRE

    Decker, Christian; Seidel, Jochen; Wattenhofer, Roger

    2014-01-01

    The Bitcoin system only provides eventual consistency. For everyday life, the time to confirm a Bitcoin transaction is prohibitively slow. In this paper we propose a new system, built on the Bitcoin blockchain, which enables strong consistency. Our system, PeerCensus, acts as a certification authority, manages peer identities in a peer-to-peer network, and ultimately enhances Bitcoin and similar systems with strong consistency. Our extensive analysis shows that PeerCensus is in a secure state...

  17. Strong gravity and supersymmetry

    International Nuclear Information System (INIS)

    Chamseddine, Ali H.; Salam, A.; Strathdee, J.

    1977-11-01

    A supersymmetric theory is constructed for a strong f plus a weak g graviton, together with their accompanying massive gravitinos, by gaugin the gradel 0Sp(2,2,1)x 0Sp(2,2,1) structure. The mixing term between f and g fields, which makes the strong graviton massive, can be introduced through a spontaneous symmetry-breaking mechanism implemented in this note by constructing a non-linear realization of the symmetry group

  18. Band parameters of phosphorene

    International Nuclear Information System (INIS)

    Lew Yan Voon, L C; Wang, J; Zhang, Y; Willatzen, M

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene. (paper)

  19. Infrared diffuse interstellar bands

    Science.gov (United States)

    Galazutdinov, G. A.; Lee, Jae-Joon; Han, Inwoo; Lee, Byeong-Cheol; Valyavin, G.; Krełowski, J.

    2017-05-01

    We present high-resolution (R ˜ 45 000) profiles of 14 diffuse interstellar bands in the ˜1.45 to ˜2.45 μm range based on spectra obtained with the Immersion Grating INfrared Spectrograph at the McDonald Observatory. The revised list of diffuse bands with accurately estimated rest wavelengths includes six new features. The diffuse band at 15 268.2 Å demonstrates a very symmetric profile shape and thus can serve as a reference for finding the 'interstellar correction' to the rest wavelength frame in the H range, which suffers from a lack of known atomic/molecular lines.

  20. Band parameters of phosphorene

    DEFF Research Database (Denmark)

    Lew Yan Voon, L. C.; Wang, J.; Zhang, Y.

    2015-01-01

    Phosphorene is a two-dimensional nanomaterial with a direct band-gap at the Brillouin zone center. In this paper, we present a recently derived effective-mass theory of the band structure in the presence of strain and electric field, based upon group theory. Band parameters for this theory...... are computed using a first-principles theory based upon the generalized-gradient approximation to the density-functional theory. These parameters and Hamiltonian will be useful for modeling physical properties of phosphorene....

  1. Confidence bands for inverse regression models

    International Nuclear Information System (INIS)

    Birke, Melanie; Bissantz, Nicolai; Holzmann, Hajo

    2010-01-01

    We construct uniform confidence bands for the regression function in inverse, homoscedastic regression models with convolution-type operators. Here, the convolution is between two non-periodic functions on the whole real line rather than between two periodic functions on a compact interval, since the former situation arguably arises more often in applications. First, following Bickel and Rosenblatt (1973 Ann. Stat. 1 1071–95) we construct asymptotic confidence bands which are based on strong approximations and on a limit theorem for the supremum of a stationary Gaussian process. Further, we propose bootstrap confidence bands based on the residual bootstrap and prove consistency of the bootstrap procedure. A simulation study shows that the bootstrap confidence bands perform reasonably well for moderate sample sizes. Finally, we apply our method to data from a gel electrophoresis experiment with genetically engineered neuronal receptor subunits incubated with rat brain extract

  2. Cyanide bridged hetero-metallic polymeric complexes: Syntheses, vibrational spectra, thermal analyses and crystal structures of complexes [M(1,2-dmi)2Ni(μ-CN)4]n (M = Zn(II) and Cd(II))

    Science.gov (United States)

    Kürkçüoğlu, Güneş Süheyla; Sayın, Elvan; Şahin, Onur

    2015-12-01

    Two cyanide bridged hetero-metallic complexes of general formula, [M(1,2-dmi)2Ni(μ-CN)4]n (1,2-dmi = 1,2-dimethylimidazole and M = Zn(II) or Cd(II)) have been synthesized and characterized by vibrational (FT-IR and Raman) spectroscopy, single crystal X-ray diffraction, thermal analyses and elemental analyses. The crystallographic analyses reveal that the complexes, [Zn(1,2-dmi)2Ni(μ-CN)4] (1) and [Cd(1,2-dmi)2Ni(μ-CN)4] (2), have polymeric 2D networks. In the complexes, four cyanide groups of [Ni(CN)4]2- coordinated to the adjacent M(II) ions and distorted octahedral geometries of complexes are completed by two nitrogen atoms of trans 1,2-dmi ligands. The structures of 1 and 2 are similar and linked via intermolecular hydrogen bonding, C-H⋯Ni interactions to give rise to 3D networks. Vibration assignments are given for all the observed bands and the spectral features also supported to the crystal structures of heteronuclear complexes. The FT-IR and Raman spectra of the complexes are very much consistent with the structural data presented.

  3. Collapse and revival in inter-band oscillations of a two-band Bose-Hubbard model

    Energy Technology Data Exchange (ETDEWEB)

    Ploetz, Patrick; Wimberger, Sandro [Institut fuer Theoretische Physik, Universitaet Heidelberg, Philosophenweg 19, 69120 Heidelberg (Germany); Madronero, Javier, E-mail: ploetz@thphys.uni-heidelberg.d [Physik Department, Technische Universitaet Muenchen, James-Franck-Str. 1, 85748 Garching (Germany)

    2010-04-28

    We study the effect of a many-body interaction on inter-band oscillations in a two-band Bose-Hubbard model with an external Stark force. Weak and strong inter-band oscillations are observed, where the latter arise from a resonant coupling of the bands. These oscillations collapse and revive due to a weak two-body interaction between the atoms. Effective models for oscillations in and out of resonance are introduced that provide predictions for the system's behaviour, particularly for the time scales for the collapse and revival of the resonant inter-band oscillations. (fast track communication)

  4. Generalized seniority scheme for bands in odd-A nuclei

    International Nuclear Information System (INIS)

    Gai, M.; Arima, A.; Strottman, D.

    1980-01-01

    The microscopic generalized seniority scheme is applied for the description of bands in odd-A nuclei. A perturbation expansion in terms of the core-particle interaction is performed. The first-order correction for the band head and the first member of the band is discussed. The specific band structure of a given nucleus, as well as the systematic trend of bands, is described in an explicit N-dependent analytical formula. This formula involves a linear dependence on N which arises from the first-order perturbation expansion. This term is shown responsible for the large deviation of the 11/2 - ΔJ=2 band spacing in I isotopes from the spacing of the Te core. All observed band structures of an odd-A nucleus arise from one simple core-particle coupling. Hence decoupled-E2 bands and strongly coupled ΔJ=1 bands, particle or hole bands of low-spin or high-spin orbits, all follow one simple N-dependence. This uniformity of bands is manifested in E2 bands in 53 I isotopes and deltaJ=1 bands in 51 Sb that have the same 52 Te cores. For the calculations a particle-particle force with a large contribution from a g delta force is used with a coupling constant that is deduced from 210 Pb. 1 figure

  5. The end of the unique myocardial band

    DEFF Research Database (Denmark)

    MacIver, David H; Partridge, John B; Agger, Peter

    2018-01-01

    Two of the leading concepts of mural ventricular architecture are the unique myocardial band and the myocardial mesh model. We have described, in an accompanying article published in this journal, how the anatomical, histological and high-resolution computed tomographic studies strongly favour th...

  6. CSF oligoclonal banding - slideshow

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/presentations/100145.htm CSF oligoclonal banding - series—Normal anatomy To use the ... 5 out of 5 Overview The cerebrospinal fluid (CSF) serves to supply nutrients to the central nervous ...

  7. Decay of superdeformed bands

    International Nuclear Information System (INIS)

    Carpenter, M.P.; Khoo, T.L.; Lauritsen, T.

    1995-01-01

    One of the major challenges in the study of superdeformation is to directly connect the large number of superdeformed bands now known to the yrast states. In this way, excitation energies, spins and parities can be assigned to the levels in the second well which is essential to establish the collective and single-particle components of these bands. This paper will review some of the progress which has been made to understand the decay of superdeformed bands using the new arrays including the measurement of the total decay spectrum and the establishment of direct one-step decays from the superdeformed band to the yrast line in 194 Hg. 42 refs., 5 figs

  8. Laparoscopic gastric banding

    Science.gov (United States)

    ... eat by making you feel full after eating small amounts of food. After surgery, your doctor can adjust the band ... You will feel full after eating just a small amount of food. The food in the small upper pouch will ...

  9. Band gap and band offset of (GaIn)(PSb) lattice matched to InP

    Science.gov (United States)

    Köhler, F.; Böhm, G.; Meyer, R.; Amann, M.-C.

    2005-07-01

    Metastable (GaxIn1-x)(PySb1-y) layers were grown on (001) InP substrates by gas source molecular beam epitaxy. Low-temperature photoluminescence spectroscopy was applied to these heterostructures and revealed spatially indirect band-to-band recombination of electrons localized in the InP with holes in the (GaxIn1-x)(PySb1-y). In addition, samples with layer thicknesses larger than 100nm showed direct PL across the band gap of (GaxIn1-x)(PySb1-y). Band-gap energies and band offset energies of (GaxIn1-x)(PySb1-y) relative to InP were derived from these PL data. A strong bowing parameter was observed.

  10. Probing the Properties of Polynuclear Superhalogens without Halogen Ligand via ab Initio Calculations: A Case Study on Double-Bridged [Mg2 (CN)5 ](-1) Anions.

    Science.gov (United States)

    Li, Jin-Feng; Li, Miao-Miao; Bai, Hongcun; Sun, Yin-Yin; Li, Jian-Li; Yin, Bing

    2015-12-01

    An ab initio study of the superhalogen properties of eighteen binuclear double-bridged [Mg2 (CN)5 ](-1) clusters is reported herein by using various theoretical methods. High-level CCSD(T) results indicate that all the clusters possess strong superhalogen properties owing to their high vertical electron detachment energies (VDEs), which exceed 6.8 eV (highest: 8.15 eV). The outer valence Green's function method provides inaccurate relative VDE values; hence, this method is not suitable for this kind of polynuclear superhalogens. Both the HF and MP2 results are generally consistent with the CCSD(T) level regarding the relative VDE values and-especially interesting-the average values of the HF and MP2 VDEs are extremely close to the CCSD(T) results. The distributions of the extra electrons of the anions are mainly aggregated into the terminal CN units. These distributions are apparently different from those of previously reported triple-bridged isomers and may be the reason for the decreased VDE values of the clusters. In addition, comparisons of the VDEs of binuclear and mononuclear superhalogens as well as studies of the thermodynamic stabilities with respect to the detachment of various CN(-1) ligands are also performed. These results confirm that polynuclear structures with pseudohalogen ligands can be considered as probable new superhalogens with enhanced properties. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Enhanced electrochemical performances of PANI using redox additive of K{sub 4}[Fe(CN){sub 6}] in aqueous electrolyte for symmetric supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Shanmugavani, A.; Kaviselvi, S.; Sankar, K.Vijaya; Selvan, R.Kalai, E-mail: selvankram@buc.edu.in

    2015-02-15

    Highlights: • Effect of K{sub 4}[Fe(CN){sub 6}] in H{sub 2}SO{sub 4} studied on the electrochemical properties of PANI. • The polaron band – π* transition reveals the emeraldine salt (conductive) form. • CV curves exhibit quasi-reversible redox behavior. • Symmetric PANI SC shows 228 F g{sup −1} at 1 mA cm{sup −2} in K{sub 4}[Fe (CN){sub 6}] added 1 M H{sub 2}SO{sub 4}. • PANI-1 symmetric supercapacitor shows almost 100% of capacity retention. - Abstract: Polyaniline (PANI) particles were prepared by reflux assisted chemical oxidative polymerization method with the aid of ammonium per sulfate/ferric chloride as oxidants and HCl/H{sub 2}SO{sub 4} as the medium. Amorphous nature and the emeraldine state of PANI were revealed from X-ray diffraction and Fourier transform infrared analysis. Moreover, ultra violet–visible spectra attributes to the polaron band – π* transition of polyaniline. The scanning electron microscopic image shows that the particle size is in the range of 0.2–2 μm. The electrochemical performances of the material were investigated in 1 M H{sub 2}SO{sub 4} and 0.08 M K{sub 4}[Fe(CN){sub 6}] added 1 M H{sub 2}SO{sub 4} aqueous electrolytes. Cyclic voltammetry and galvanostatic charge–discharge studies were carried out to find its suitability as a supercapacitor electrode material. The charge discharge analysis of the fabricated symmetric supercapacitors revealed the fact that the electrolyte containing redox additive (0.08 M K{sub 4}[Fe(CN){sub 6}]) delivered an enhanced specific capacitance of 228 F g{sup −1} (∼912 F g{sup −1} for single electrode) than that of 1 M H{sub 2}SO{sub 4} (100 F g{sup −1}) at 1 mA cm{sup −2}. Further cycling stability is performed at 5 mA cm{sup −2} ensures the durability of the supercapacitor.

  12. Reactions of the CN Radical with Benzene and Toluene: Product Detection and Low-Temperature Kinetics

    Energy Technology Data Exchange (ETDEWEB)

    Trevitt, Adam J.; Goulay, Fabien; Taatjes, Craig A.; Osborn, David L.; Leone, Stephen R.

    2009-12-23

    Low temperature rate coefficients are measured for the CN + benzene and CN + toluene reactions using the pulsed Laval nozzle expansion technique coupled with laser-induced fluorescence detection. The CN + benzene reaction rate coefficient at 105, 165 and 295 K is found to be relatively constant over this temperature range, 3.9 - 4.9 x 10-10 cm3 molecule-1 s-1. These rapid kinetics, along with the observed negligible temperature dependence, are consistent with a barrierless reaction entrance channel and reaction efficiencies approaching unity. The CN + toluene reaction is measured to have a slower rate coefficient of 1.3 x 10-10 cm3 molecule-1 s-1 at 105 K. At room temperature, non-exponential decay profiles are observed for this reaction that may suggest significant back-dissociation of intermediate complexes. In separate experiments, the products of these reactions are probed at room temperature using synchrotron VUV photoionization mass spectrometry. For CN + benzene, cyanobenzene (C6H5CN) is the only product recorded with no detectable evidence for a C6H5 + HCN product channel. In the case of CN + toluene, cyanotoluene (NCC6H4CH3) constitutes the only detected product. It is not possible to differentiate among the ortho, meta and para isomers of cyanotoluene because of their similar ionization energies and the ~;; 40 meV photon energy resolution of the experiment. There is no significant detection of benzyl radicals (C6H5CH2) that would suggest a H-abstraction or a HCN elimination channel is prominent at these conditions. As both reactions are measured to be rapid at 105 K, appearing to have barrierless entrance channels, it follows that they will proceed efficiently at the temperatures of Saturn?s moon Titan (~;;100 K) and are also likely to proceed at the temperature of interstellar clouds (10-20 K).

  13. Combined treatment with cotylenin A and phenethyl isothiocyanate induces strong antitumor activity mainly through the induction of ferroptotic cell death in human pancreatic cancer cells.

    Science.gov (United States)

    Kasukabe, Takashi; Honma, Yoshio; Okabe-Kado, Junko; Higuchi, Yusuke; Kato, Nobuo; Kumakura, Shunichi

    2016-08-01

    The treatment of pancreatic cancer, one of the most aggressive gastrointestinal tract malignancies, with current chemotherapeutic drugs has had limited success due to its chemoresistance and poor prognosis. Therefore, the development of new drugs or effective combination therapies is urgently needed. Cotylenin A (CN-A) (a plant growth regulator) is a potent inducer of differentiation in myeloid leukemia cells and exhibits potent antitumor activities in several cancer cell lines. In the present study, we demonstrated that CN-A and phenethyl isothiocyanate (PEITC), an inducer of reactive oxygen species (ROS) and a dietary anticarcinogenic compound, synergistically inhibited the proliferation of MIAPaCa-2, PANC-1 and gemcitabine-resistant PANC-1 cells. A combined treatment with CN-A and PEITC also effectively inhibited the anchorage-independent growth of these cancer cells. The combined treatment with CN-A and PEITC strongly induced cell death within 1 day at concentrations at which CN-A or PEITC alone did not affect cell viability. A combined treatment with synthetic CN-A derivatives (ISIR-005 and ISIR-042) or fusicoccin J (CN-A-related natural product) and PEITC did not have synergistic effects on cell death. The combined treatment with CN-A and PEITC synergistically induced the generation of ROS. Antioxidants (N-acetylcysteine and trolox), ferroptosis inhibitors (ferrostatin-1 and liproxstatin), and the lysosomal iron chelator deferoxamine canceled the synergistic cell death. Apoptosis inhibitors (Z-VAD-FMK and Q-VD-OPH) and the necrosis inhibitor necrostatin-1s did not inhibit synergistic cell death. Autophagy inhibitors (3-metyladenine and chloroquine) partially prevented cell death. These results show that synergistic cell death induced by the combined treatment with CN-A and PEITC is mainly due to the induction of ferroptosis. Therefore, the combination of CN-A and PEITC has potential as a novel therapeutic strategy against pancreatic cancer.

  14. Designing new catalytic C-C and C-N bond formations promoted by organoactinides

    International Nuclear Information System (INIS)

    Eisen, M.S.; Straub, T.; Haskel, A.

    1998-01-01

    Organoactinides of the type Cp 2 * AcMe 2 (Cp * =C 5 Me 5 ; Ac=Th; U) are active catalytic precursors for the oligomerization of terminal alkynes HC≡CR (R=alkyl, aryl, SiMe 3 ). The regioselectivity and the extent of oligomerization depend strongly on the alkyne substituent R, whereas the catalytic reactivity is similar for both organoactinides. Reaction with tert-butylacetylene yields regioselectively the E-2,4-disubstituted 1-buten-3-yne dimer whereas trimethylsilylacetylene is regioselective trimerized to the E,E-1,4,6-tris(trimethylsilyl)-1,3-hexa diene-5-yne, with small amounts (3-5%) of the corresponding E-2,4-disubstituted 1-buten-3-yne dimer. Oligomerization with less bulky alkyl and aryl substituted alkynes produces a mixture of higher oligomers with no regioselectivity. Using the Cp 2 * ThMe 2 catalyst, we have recently developed a strategic method to control the extent and in some cases the regioselectivity of the catalyzed oligomerization of nonbulky terminal alkynes to dimers and/or trimers. The metallocene catalytic precursors ensure the selective synthesis of small oligomers by the addition of specific amines. Catalytic ''tailoring'' to dimer and trimers can be achieved by using small or bulky amines, respectively. Kinetic and mechanistic data for the controlling experiments argue that the turnover-limiting step involves the acetylide actinide complex formation with the rapid insertion of the alkyne and protonolysis by the amine. The analog Cp 2 * UMe 2 in the presence of primary amines induce the selective C-N bond formation, producing enamines which are tautomerized to the corresponding imines. (orig.)

  15. Strongly interacting Fermi gases

    Directory of Open Access Journals (Sweden)

    Bakr W.

    2013-08-01

    Full Text Available Strongly interacting gases of ultracold fermions have become an amazingly rich test-bed for many-body theories of fermionic matter. Here we present our recent experiments on these systems. Firstly, we discuss high-precision measurements on the thermodynamics of a strongly interacting Fermi gas across the superfluid transition. The onset of superfluidity is directly observed in the compressibility, the chemical potential, the entropy, and the heat capacity. Our measurements provide benchmarks for current many-body theories on strongly interacting fermions. Secondly, we have studied the evolution of fermion pairing from three to two dimensions in these gases, relating to the physics of layered superconductors. In the presence of p-wave interactions, Fermi gases are predicted to display toplogical superfluidity carrying Majorana edge states. Two possible avenues in this direction are discussed, our creation and direct observation of spin-orbit coupling in Fermi gases and the creation of fermionic molecules of 23Na 40K that will feature strong dipolar interactions in their absolute ground state.

  16. A strong comeback

    International Nuclear Information System (INIS)

    Marier, D.

    1992-01-01

    This article presents the results of a financial rankings survey which show a strong economic activity in the independent energy industry. The topics of the article include advisor turnover, overseas banks, and the increase in public offerings. The article identifies the top project finance investors for new projects and restructurings and rankings for lenders

  17. Application of GIS-based SCS-CN method in West Bank catchments, Palestine

    Directory of Open Access Journals (Sweden)

    Sameer Shadeed

    2010-03-01

    Full Text Available Among the most basic challenges of hydrology are the prediction and quantification of catchment surface runoff. The runoff curve number (CN is a key factor in determining runoff in the SCS (Soil Conservation Service based hydrologic modeling method. The traditional SCS-CN method for calculating the composite curve number is very tedious and consumes a major portion of the hydrologic modeling time. Therefore, geographic information systems (GIS are now being used in combination with the SCS-CN method. This paper assesses the modeling of flow in West Bank catchments using the GIS-based SCS-CN method. The West Bank, Palestine, is characterized as an arid to semi-arid region with annual rainfall depths ranging between 100 mm in the vicinity of the Jordan River to 700 mm in the mountains extending across the central parts of the region. The estimated composite curve number for the entire West Bank is about 50 assuming dry conditions. This paper clearly demonstrates that the integration of GIS with the SCS-CN method provides a powerful tool for estimating runoff volumes in West Bank catchments, representing arid to semi-arid catchments of Palestine.

  18. Synthesis of SiCN@TiO2 core-shell ceramic microspheres via PDCs method

    Science.gov (United States)

    Liu, Hongli; Wei, Ning; Li, Jing; Zhang, Haiyuan; Chu, Peng

    2018-02-01

    A facile and effective polymer-derived ceramics (PDCs) emulsification-crosslinking-pyrolysis method was developed to fabricate SiCN@TiO2 core-shell ceramic microspheres with polyvinylsilazane (PVSZ) and tetrabutyl titanate (TBT) as precursors. The TBT: PVSZ mass ratios, emulsifier concentrations and the pyrolysis temperature were examined as control parameters to tune the size and morphology of microspheres. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) confirmed the synthesized SiCN@TiO2 microspheres to be comprised of SiCN core coated with TiO2 crystals, with an average size of 0.88 μm when pyrolyzed at 1400 °C. The analysis of Fourier transform infrared spectroscopy (FT-IR), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD) ensured that SiCN@TiO2 core-shell ceramic microspheres composed of rutile TiO2, β-SiC and Si3N4 crystalline phases, The thermal properties were characterized by thermogravimetric analysis (TGA). The obtained SiCN@TiO2 core-shell ceramic microspheres were the promising candidate of the infrared opacifier in silica aerogels and this technique can be extended to other preceramic polymers.

  19. WebCN: A web-based computation tool for in situ-produced cosmogenic nuclides

    Energy Technology Data Exchange (ETDEWEB)

    Ma Xiuzeng [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)]. E-mail: hongju@purdue.edu; Li Yingkui [Department of Geography, University of Missouri-Columbia, Columbia, MO 65211 (United States); Bourgeois, Mike [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Caffee, Marc [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Elmore, David [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Granger, Darryl [Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, IN 47907 (United States); Muzikar, Paul [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States); Smith, Preston [Department of Physics, Purdue University, West Lafayette, IN 47907 (United States)

    2007-06-15

    Cosmogenic nuclide techniques are increasingly being utilized in geoscience research. For this it is critical to establish an effective, easily accessible and well defined tool for cosmogenic nuclide computations. We have been developing a web-based tool (WebCN) to calculate surface exposure ages and erosion rates based on the nuclide concentrations measured by the accelerator mass spectrometry. WebCN for {sup 10}Be and {sup 26}Al has been finished and published at http://www.physics.purdue.edu/primelab/for{sub u}sers/rockage.html. WebCN for {sup 36}Cl is under construction. WebCN is designed as a three-tier client/server model and uses the open source PostgreSQL for the database management and PHP for the interface design and calculations. On the client side, an internet browser and Microsoft Access are used as application interfaces to access the system. Open Database Connectivity is used to link PostgreSQL and Microsoft Access. WebCN accounts for both spatial and temporal distributions of the cosmic ray flux to calculate the production rates of in situ-produced cosmogenic nuclides at the Earth's surface.

  20. Strong seismic ground motion propagation

    International Nuclear Information System (INIS)

    Seale, S.; Archuleta, R.; Pecker, A.; Bouchon, M.; Mohammadioun, G.; Murphy, A.; Mohammadioun, B.

    1988-10-01

    At the McGee Creek, California, site, 3-component strong-motion accelerometers are located at depths of 166 m, 35 m and 0 m. The surface material is glacial moraine, to a depth of 30.5 m, overlying homfels. Accelerations were recorded from two California earthquakes: Round Valley, M L 5.8, November 23, 1984, 18:08 UTC and Chalfant Valley, M L 6.4, July 21, 1986, 14:42 UTC. By separating out the SH components of acceleration, we were able to determine the orientations of the downhole instruments. By separating out the SV component of acceleration, we were able to determine the approximate angle of incidence of the signal at 166 m. A constant phase velocity Haskell-Thomson model was applied to generate synthetic SH seismograms at the surface using the accelerations recorded at 166 m. In the frequency band 0.0 - 10.0 Hz, we compared the filtered synthetic records to the filtered surface data. The onset of the SH pulse is clearly seen, as are the reflections from the interface at 30.5 m. The synthetic record closely matches the data in amplitude and phase. The fit between the synthetic accelerogram and the data shows that the seismic amplification at the surface is a result of the contrast of the impedances (shear stiffnesses) of the near surface materials

  1. Wurtzite gallium phosphide has a direct-band gap

    NARCIS (Netherlands)

    Assali, S.; Zardo, I.; Plissard, S.; Verheijen, M.A.; Haverkort, J.E.M.; Bakkers, E.P.A.M.

    2013-01-01

    Gallium Phosphide (GaP) with the normal cubic crystal structure has an indirect band gap, which severely limits the emission efficiency. We report the fabrication of GaP nanowires with pure hexagonal crystal structure and demonstrate the direct nature of the band gap. We observe strong

  2. Strong Electroweak Symmetry Breaking

    CERN Document Server

    Grinstein, Benjamin

    2011-01-01

    Models of spontaneous breaking of electroweak symmetry by a strong interaction do not have fine tuning/hierarchy problem. They are conceptually elegant and use the only mechanism of spontaneous breaking of a gauge symmetry that is known to occur in nature. The simplest model, minimal technicolor with extended technicolor interactions, is appealing because one can calculate by scaling up from QCD. But it is ruled out on many counts: inappropriately low quark and lepton masses (or excessive FCNC), bad electroweak data fits, light scalar and vector states, etc. However, nature may not choose the minimal model and then we are stuck: except possibly through lattice simulations, we are unable to compute and test the models. In the LHC era it therefore makes sense to abandon specific models (of strong EW breaking) and concentrate on generic features that may indicate discovery. The Technicolor Straw Man is not a model but a parametrized search strategy inspired by a remarkable generic feature of walking technicolor,...

  3. Plasmons in strong superconductors

    International Nuclear Information System (INIS)

    Baldo, M.; Ducoin, C.

    2011-01-01

    We present a study of the possible plasmon excitations that can occur in systems where strong superconductivity is present. In these systems the plasmon energy is comparable to or smaller than the pairing gap. As a prototype of these systems we consider the proton component of Neutron Star matter just below the crust when electron screening is not taken into account. For the realistic case we consider in detail the different aspects of the elementary excitations when the proton, electron components are considered within the Random-Phase Approximation generalized to the superfluid case, while the influence of the neutron component is considered only at qualitative level. Electron screening plays a major role in modifying the proton spectrum and spectral function. At the same time the electron plasmon is strongly modified and damped by the indirect coupling with the superfluid proton component, even at moderately low values of the gap. The excitation spectrum shows the interplay of the different components and their relevance for each excitation modes. The results are relevant for neutrino physics and thermodynamical processes in neutron stars. If electron screening is neglected, the spectral properties of the proton component show some resemblance with the physical situation in high-T c superconductors, and we briefly discuss similarities and differences in this connection. In a general prospect, the results of the study emphasize the role of Coulomb interaction in strong superconductors.

  4. Itinerant ferromagnetism in the narrow band limit

    CERN Document Server

    Liu, S H

    2000-01-01

    It is shown that in the narrow band, strong interaction limit the paramagnetic state of an itinerant ferromagnet is described by the disordered local moment state. As a result, the Curie temperature is orders of magnitude lower than what is expected from the large exchange splitting of the spin bands. An approximate analysis has also been carried out for the partially ordered state, and the result explains the temperature evolvement of the magnetic contributions to the resistivity and low-energy optical conductivity of CrO sub 2.

  5. Ultra wide band antennas

    CERN Document Server

    Begaud, Xavier

    2013-01-01

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

  6. Synergy between erosion-corrosion of steel AISI 4140 covered by a multilayer TiCN / TiNbCN, at an impact angle of 90°

    Directory of Open Access Journals (Sweden)

    Willian Aperador Chaparro

    2013-01-01

    Full Text Available El propósito de este trabajo es estudiar el efecto de la erosión corrosión en el desgaste de los recubrimientos en forma de multicapas de [TiCN / TiNbCN] n depositadas sobre sustratos de acero AISI 4140. El crecimiento de las multicapas de [TiCN / TiNbCN] n se realizó mediante un sistema magnetrón sputtering con RF reactivo en el que se varió sistemáticamente el período bicapa (Λ, y el número bicapa (n, manteniendo constante el espesor total de las capas (~ 3 micras. Las multicapas se evaluaron comparando la corrosión, erosión y erosión – corrosión a un ángulo de impacto de 90 º en una solución de 0,5 M de NaCl y de sílice, analizando el número de bicapas sobre en la resistencia a la corrosión de estos recubrimientos. Las curvas de polarización se realizaron en el potencial de reposo. Posteriormente de la realización de los experimentos de las curvas de polarización las muestras se analizaron por microscopía electrónica de barrido. Los resultados muestran que el buen rendimiento de los sistemas multicapa en sistemas dinámicos de corrosión y corrosión por erosión y la mejora de desgaste es debido al hecho de que las curvas de polarización se mueven hacia las zonas donde las densidades de corriente disminuyen al aumentar el número de bicapas.

  7. G331.512–0.103: An Interstellar Laboratory for Molecular Synthesis. I. The Ortho-to-para Ratios for CH3OH and CH3CN

    Science.gov (United States)

    Mendoza, Edgar; Bronfman, Leonardo; Duronea, Nicolas U.; Lépine, Jacques R. D.; Finger, Ricardo; Merello, Manuel; Hervías-Caimapo, Carlos; Gama, Diana R. G.; Reyes, Nicolas; Åke-Nyman, Lars

    2018-02-01

    Spectral line surveys reveal rich molecular reservoirs in G331.512–0.103, a compact radio source in the center of an energetic molecular outflow. In this first work, we analyze the physical conditions of the source by means of CH3OH and CH3CN. The observations were performed with the APEX Telescope. Six different system configurations were defined to cover most of the band within (292–356) GHz as a consequence, we detected a forest of lines toward the central core. A total of 70 lines of A/E–CH3OH and A/E–CH3CN were analyzed, including torsionally excited transitions of CH3OH ({ν }t=1). In a search for all the isotopologues, we identified transitions of 13CH3OH. The physical conditions were derived considering collisional and radiative processes. We found common temperatures for each A and E symmetry of CH3OH and CH3CN; the derived column densities indicate an A/E equilibrated ratio for both tracers. The results reveal that CH3CN and CH3OH trace a hot and cold component with {T}k∼ 141 K and {T}k∼ 74 K, respectively. In agreement with previous ALMA observations, the models show that the emission region is compact (≲ 5\\buildrel{\\prime\\prime}\\over{.} 5) with gas density n(H2) = (0.7–1)×107 cm‑3. The CH3OH/CH3CN abundance ratio and the evidences for prebiotic and complex organic molecules suggest a rich and active chemistry toward G331.512–0.103.

  8. Preliminary verification of structure design for CN HCCB TBM with 1 × 4 configuration

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Zhou, E-mail: zhaozhou@swip.ac.cn; Zhou, Bing; Wang, Qijie; Cao, Qixiang; Feng, Kaiming; Wang, Xiaoyu; Zhang, Guoshu

    2016-02-15

    Highlights: • A new and simplification structural design scheme with 1 × 4 configuration is proposed for CN HCCB TBM. • The detail conceptual structural design for 1 × 4 TBM is completed. • The preliminary hydraulic analysis, thermo-hydraulic analysis and structural analysis for 1 × 4 TBM had been carried out. - Abstract: Based on the conceptual design of CN HCCB TBM with 1 × 4 configuration, the preliminary hydraulic analysis, thermo-hydraulic analysis and structural analysis had been carried out for it. Hydraulic and thermo-hydraulic analyses show that the coolant manifold system could meet the fluid design requirement preliminarily and the temperature of RAFMs structural parts, Be and Li{sub 4}SiO{sub 4} pebble beds are within the allowable range, and no zone shows a stress higher than the allowable limit in the preliminary structural analysis. These results indicate the design for CN HCCB TBM with 1 × 4 configuration is preliminary reasonable.

  9. 2D water layer enclathrated between Mn(II)-Ni(CN)4 coordination frameworks

    International Nuclear Information System (INIS)

    Ray, Ambarish; Bhowmick, Indrani; Sheldrick, William S.; Jana, Atish Dipankar; Ali, Mahammed

    2009-01-01

    A [Ni(CN) 4 ] 2- based two-dimensional Mn(II) coordination polymer {Mn(H 2 O) 2 [NiCN] 4 .4H 2 O}, in which the coordination layers are stacked on top of each other sandwiching 2D water layer of boat-shaped hexagonal water clusters has been synthesized. The complex exhibits high thermal decomposition temperature and reversible water absorption, which were clearly demonstrated by thermal and PXRD studies on the parent and rehydrated complex after dehydration. - Abstract: A coordination polymer, {Mn(H 2 O) 2 [NiCN] 4 .4H 2 O} n , showed that the coordination layers are stacked on top of each other sandwiching 2D ice layer of boat-shaped hexagonal water clusters . Display Omitted

  10. Preliminary verification of structure design for CN HCCB TBM with 1 × 4 configuration

    International Nuclear Information System (INIS)

    Zhao, Zhou; Zhou, Bing; Wang, Qijie; Cao, Qixiang; Feng, Kaiming; Wang, Xiaoyu; Zhang, Guoshu

    2016-01-01

    Highlights: • A new and simplification structural design scheme with 1 × 4 configuration is proposed for CN HCCB TBM. • The detail conceptual structural design for 1 × 4 TBM is completed. • The preliminary hydraulic analysis, thermo-hydraulic analysis and structural analysis for 1 × 4 TBM had been carried out. - Abstract: Based on the conceptual design of CN HCCB TBM with 1 × 4 configuration, the preliminary hydraulic analysis, thermo-hydraulic analysis and structural analysis had been carried out for it. Hydraulic and thermo-hydraulic analyses show that the coolant manifold system could meet the fluid design requirement preliminarily and the temperature of RAFMs structural parts, Be and Li_4SiO_4 pebble beds are within the allowable range, and no zone shows a stress higher than the allowable limit in the preliminary structural analysis. These results indicate the design for CN HCCB TBM with 1 × 4 configuration is preliminary reasonable.

  11. Co-composting of green waste and food waste at low C/N ratio

    International Nuclear Information System (INIS)

    Kumar, Mathava; Ou, Y.-L.; Lin, J.-G.

    2010-01-01

    In this study, co-composting of food waste and green waste at low initial carbon to nitrogen (C/N) ratios was investigated using an in-vessel lab-scale composting reactor. The central composite design (CCD) and response surface method (RSM) were applied to obtain the optimal operating conditions over a range of preselected moisture contents (45-75%) and C/N ratios (13.9-19.6). The results indicate that the optimal moisture content for co-composting of food waste and green waste is 60%, and the substrate at a C/N ratio of 19.6 can be decomposed effectively to reduce 33% of total volatile solids (TVS) in 12 days. The TVS reduction can be modeled by using a second-order equation with a good fit. In addition, the compost passes the standard germination index of white radish seed indicating that it can be used as soil amendment.

  12. Synthesis of polypyrrole within the cell wall of yeast by redox-cycling of [Fe(CN)6](3-)/[Fe(CN)6](4-).

    Science.gov (United States)

    Ramanavicius, Arunas; Andriukonis, Eivydas; Stirke, Arunas; Mikoliunaite, Lina; Balevicius, Zigmas; Ramanaviciene, Almira

    2016-02-01

    Yeast cells are often used as a model system in various experiments. Moreover, due to their high metabolic activity, yeast cells have a potential to be applied as elements in the design of biofuel cells and biosensors. However a wider application of yeast cells in electrochemical systems is limited due to high electric resistance of their cell wall. In order to reduce this problem we have polymerized conducting polymer polypyrrole (Ppy) directly in the cell wall and/or within periplasmic membrane. In this research the formation of Ppy was induced by [Fe(CN)6](3-)ions, which were generated from K4[Fe(CN)6], which was initially added to polymerization solution. The redox process was catalyzed by oxido-reductases, which are present in the plasma membrane of yeast cells. The formation of Ppy was confirmed by spectrophotometry and atomic force microscopy. It was confirmed that the conducting polymer polypyrrole was formed within periplasmic space and/or within the cell wall of yeast cells, which were incubated in solution containing pyrrole, glucose and [Fe(CN)6](4-). After 24h drying at room temperature we have observed that Ppy-modified yeast cell walls retained their initial spherical form. In contrast to Ppy-modified cells, the walls of unmodified yeast have wrinkled after 24h drying. The viability of yeast cells in the presence of different pyrrole concentrations has been evaluated. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. K4 Fe(CN)6 as a spectrophotometric agent for uranium analysis

    International Nuclear Information System (INIS)

    Soedyartomo; Tarwita.

    1976-01-01

    The properties of K 4 Fe(CN) 6 as a spectrophotometric agent for Uranium analysis was observed by putting some experiment into practice. The experiment covers the observation of expanding colour stability, the optimization of operating condition (p,H. and wavelength), the effect of K 4 Fe(CN) 6 concentration and the preparation of its standard curves (transmitansion vs uranium concentration) and the observation of the interfering metal spectra s (Cu ++ , Fe ++ ) either of its mixtures or themselves alone, has been carried out. The result and discussion on it are given. (author)

  14. The effects of sunlight exposure on the neutron response of CN-85 track detector

    International Nuclear Information System (INIS)

    Ahmad, N.; Mirza, N.M.; Mirza, S.K.; Tufail, M.

    1996-01-01

    The effect of sunlight exposure on the neutron response of CN-85 track detectors has been studied. It has been observed that the response during the first 28 days of sunlight exposure is slightly enhanced (10%) and then deceases continuously with increase in the sunlight exposure. After 84 days of sunlight exposure the response of the exposed detector relative to an unexposed detector is only 22%. It is also observed that the response can not be maintained by wrapping the CN-85 etch track detectors in typewriter black carbon papers if they are exposed to sunlight. (author)

  15. Wireless passive polymer-derived SiCN ceramic sensor with integrated resonator/antenna

    Science.gov (United States)

    Li, Yan; Yu, Yuxi; San, Haisheng; Wang, Yansong; An, Linan

    2013-10-01

    This paper presents a passive wireless polymer-derived silicon carbonitride (SiCN) ceramic sensor based on cavity radio frequency resonator together with integrated slot antenna. The effect of the cavity sensor dimensions on the Q-factor and resonant frequency is investigated by numerical simulation. A sensor with optimal dimensions is designed and fabricated. It is demonstrated that the sensor signal can be wirelessly detected at distances up to 20 mm. Given the high-temperature stability of the SiCN, the sensor is very promising for high-temperature wireless sensing applications.

  16. Electronic Switch in the Carbon-Centered [Re12CS17(CN6] n−Nanocluster

    Directory of Open Access Journals (Sweden)

    Gabuda SP

    2009-01-01

    Full Text Available Abstract An abrupt change in internuclear Re–Re distances between {Re6} subunits in the carbon-centered [Re12μ6-CS17(CN6] n−complexes caused by the change of the oxidation state (n = 6, 8 is first theoretically shown to be possibly controlled by an external electric field.13C NMR signal is shown to change over ~400 ppm (~37G for μ6-C atom together withn. Thereby, the metal cluster [Re12μ6-CS17(CN6] n−can be considered as a perspective model of a molecular switch.

  17. Strongly intensive quantities

    International Nuclear Information System (INIS)

    Gorenstein, M. I.; Gazdzicki, M.

    2011-01-01

    Analysis of fluctuations of hadron production properties in collisions of relativistic particles profits from use of measurable intensive quantities which are independent of system size variations. The first family of such quantities was proposed in 1992; another is introduced in this paper. Furthermore we present a proof of independence of volume fluctuations for quantities from both families within the framework of the grand canonical ensemble. These quantities are referred to as strongly intensive ones. Influence of conservation laws and resonance decays is also discussed.

  18. Strong-coupling approximations

    International Nuclear Information System (INIS)

    Abbott, R.B.

    1984-03-01

    Standard path-integral techniques such as instanton calculations give good answers for weak-coupling problems, but become unreliable for strong-coupling. Here we consider a method of replacing the original potential by a suitably chosen harmonic oscillator potential. Physically this is motivated by the fact that potential barriers below the level of the ground-state energy of a quantum-mechanical system have little effect. Numerically, results are good, both for quantum-mechanical problems and for massive phi 4 field theory in 1 + 1 dimensions. 9 references, 6 figures

  19. Strongly disordered superconductors

    International Nuclear Information System (INIS)

    Muttalib, K.A.

    1982-01-01

    We examine some universal effects of strong non-magnetic disorder on the electron-phonon and electron-electron interactions in a superconductor. In particular we explicitly take into account the effect of slow diffusion of electrons in a disordered medium by working in an exact impurity eigenstate representation. We find that the normal diffusion of electrons characterized by a constant diffusion coefficient does not lead to any significant correction to the electron-phonon or the effective electron-electron interactions in a superconductor. We then consider sufficiently strong disorder where Anderson localization of electrons becomes important and determine the effect of localization on the electron-electron interactions. We find that due to localization, the diffusion of electrons becomes anomalous in the sense that the diffusion coefficient becomes scale dependent. This results in an increase in the effective electron-electron interaction with increasing disorder. We propose that this provides a natural explanation for the unusual sensitivity of the transition temperature T/sub c/ of the high T/sub c/ superconductors (T/sub c/ > 10 0 K) to damage effects

  20. Strong Coupling Holography

    CERN Document Server

    Dvali, Gia

    2009-01-01

    We show that whenever a 4-dimensional theory with N particle species emerges as a consistent low energy description of a 3-brane embedded in an asymptotically-flat (4+d)-dimensional space, the holographic scale of high-dimensional gravity sets the strong coupling scale of the 4D theory. This connection persists in the limit in which gravity can be consistently decoupled. We demonstrate this effect for orbifold planes, as well as for the solitonic branes and string theoretic D-branes. In all cases the emergence of a 4D strong coupling scale from bulk holography is a persistent phenomenon. The effect turns out to be insensitive even to such extreme deformations of the brane action that seemingly shield 4D theory from the bulk gravity effects. A well understood example of such deformation is given by large 4D Einstein term in the 3-brane action, which is known to suppress the strength of 5D gravity at short distances and change the 5D Newton's law into the four-dimensional one. Nevertheless, we observe that the ...

  1. Band-notched spiral antenna

    Science.gov (United States)

    Jeon, Jae; Chang, John

    2018-03-13

    A band-notched spiral antenna having one or more spiral arms extending from a radially inner end to a radially outer end for transmitting or receiving electromagnetic radiation over a frequency range, and one or more resonance structures positioned adjacent one or more segments of the spiral arm associated with a notch frequency band or bands of the frequency range so as to resonate and suppress the transmission or reception of electromagnetic radiation over said notch frequency band or bands.

  2. Band connectivity for topological quantum chemistry: Band structures as a graph theory problem

    Science.gov (United States)

    Bradlyn, Barry; Elcoro, L.; Vergniory, M. G.; Cano, Jennifer; Wang, Zhijun; Felser, C.; Aroyo, M. I.; Bernevig, B. Andrei

    2018-01-01

    The conventional theory of solids is well suited to describing band structures locally near isolated points in momentum space, but struggles to capture the full, global picture necessary for understanding topological phenomena. In part of a recent paper [B. Bradlyn et al., Nature (London) 547, 298 (2017), 10.1038/nature23268], we have introduced the way to overcome this difficulty by formulating the problem of sewing together many disconnected local k .p band structures across the Brillouin zone in terms of graph theory. In this paper, we give the details of our full theoretical construction. We show that crystal symmetries strongly constrain the allowed connectivities of energy bands, and we employ graph theoretic techniques such as graph connectivity to enumerate all the solutions to these constraints. The tools of graph theory allow us to identify disconnected groups of bands in these solutions, and so identify topologically distinct insulating phases.

  3. LIGO: The strong belief

    CERN Multimedia

    Antonella Del Rosso

    2016-01-01

    Twenty years of designing, building and testing a number of innovative technologies, with the strong belief that the endeavour would lead to a historic breakthrough. The Bulletin publishes an abstract of the Courier’s interview with Barry Barish, one of the founding fathers of LIGO.   The plots show the signals of gravitational waves detected by the twin LIGO observatories at Livingston, Louisiana, and Hanford, Washington. (Image: Caltech/MIT/LIGO Lab) On 11 February, the Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo collaborations published a historic paper in which they showed a gravitational signal emitted by the merger of two black holes. These results come after 20 years of hard work by a large collaboration of scientists operating the two LIGO observatories in the US. Barry Barish, Linde Professor of Physics, Emeritus at the California Institute of Technology and former Director of the Global Design Effort for the Internat...

  4. Strongly interacting Higgs bosons

    International Nuclear Information System (INIS)

    Appelquist, T.; Bernard, C.

    1980-01-01

    The sensitivity of present-energy weak interactions to a strongly interacting heavy-Higgs-boson sector is discussed. The gauged nonlinear sigma model, which is the limit of the linear model as the Higgs-boson mass goes to infinity, is used to organize and catalogue all possible heavy-Higgs-boson effects. As long as the SU(2)/sub L/ x SU(2)/sub R/ symmetry of the Higgs sector is preserved, these effects are found to be small, of the order of the square of the gauge coupling times logarithms (but not powers) of the Higgs-boson mass divided by the W mass. We work in the context of a simplified model with gauge group SU(2)/sub L/; the extension to SU(2)/sub L/ x U(1) is briefly discussed

  5. Evaluation of SCS-CN method using a fully distributed physically based coupled surface-subsurface flow model

    Science.gov (United States)

    Shokri, Ali

    2017-04-01

    The hydrological cycle contains a wide range of linked surface and subsurface flow processes. In spite of natural connections between surface water and groundwater, historically, these processes have been studied separately. The current trend in hydrological distributed physically based model development is to combine distributed surface water models with distributed subsurface flow models. This combination results in a better estimation of the temporal and spatial variability of the interaction between surface and subsurface flow. On the other hand, simple lumped models such as the Soil Conservation Service Curve Number (SCS-CN) are still quite common because of their simplicity. In spite of the popularity of the SCS-CN method, there have always been concerns about the ambiguity of the SCS-CN method in explaining physical mechanism of rainfall-runoff processes. The aim of this study is to minimize these ambiguity by establishing a method to find an equivalence of the SCS-CN solution to the DrainFlow model, which is a fully distributed physically based coupled surface-subsurface flow model. In this paper, two hypothetical v-catchment tests are designed and the direct runoff from a storm event are calculated by both SCS-CN and DrainFlow models. To find a comparable solution to runoff prediction through the SCS-CN and DrainFlow, the variance between runoff predictions by the two models are minimized by changing Curve Number (CN) and initial abstraction (Ia) values. Results of this study have led to a set of lumped model parameters (CN and Ia) for each catchment that is comparable to a set of physically based parameters including hydraulic conductivity, Manning roughness coefficient, ground surface slope, and specific storage. Considering the lack of physical interpretation in CN and Ia is often argued as a weakness of SCS-CN method, the novel method in this paper gives a physical explanation to CN and Ia.

  6. Nano-galvanic coupling for enhanced Ag+ release in ZrCN-Ag films : Antibacterial application

    NARCIS (Netherlands)

    Calderon, S.; Ferreri, I.; Henriques, M.; De Hosson, J. T. M.; Cavaleiro, A.; Carvalho, S.

    2016-01-01

    The antibacterial properties of materials developed for medical devices with embedded silver nanoparticles are enhanced by controlling the release of silver ions. In this study, a simple experimental procedure for the augmentation of the silver ion release from ZrCN-Ag coatings is described. The

  7. Sheet-like of Mo –Sm assembly containing [Mo (CN)8 ] and Sm ions ...

    Indian Academy of Sciences (India)

    Administrator

    421–427. © Indian Academy of Sciences. 421 ... Department of Chemistry, Nankai University, Tianjin, 300071, PR China e-mail: ... [Mo(CN)8]3– building blocks, this paper details the ..... 20601014), and National Basic Research Program of.

  8. Radiological Protection Service of CN Asco; Servicio de ProteccionRadiologica de C. N. Asco

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    Briefly explains the structure of Radiation Protection Service (SPR) of CN Asco to address these performances, as well as a short description of the main activities that have been reinforced or have been incorporated into the routine activities of the SPR. (Author)

  9. A Survey of CH3CN and HC3N in Protoplanetary Disks

    Science.gov (United States)

    Bergner, Jennifer B.; Guzmán, Viviana G.; Öberg, Karin I.; Loomis, Ryan A.; Pegues, Jamila

    2018-04-01

    The organic content of protoplanetary disks sets the initial compositions of planets and comets, thereby influencing subsequent chemistry that is possible in nascent planetary systems. We present observations of the complex nitrile-bearing species CH3CN and HC3N toward the disks around the T Tauri stars AS 209, IM Lup, LkCa 15, and V4046 Sgr as well as the Herbig Ae stars MWC 480 and HD 163296. HC3N is detected toward all disks except IM Lup, and CH3CN is detected toward V4046 Sgr, MWC 480, and HD 163296. Rotational temperatures derived for disks with multiple detected lines range from 29 to 73 K, indicating emission from the temperate molecular layer of the disk. V4046 Sgr and MWC 480 radial abundance profiles are constrained using a parametric model; the gas-phase CH3CN and HC3N abundances with respect to HCN are a few to tens of percent in the inner 100 au of the disk, signifying a rich nitrile chemistry at planet- and comet-forming disk radii. We find consistent relative abundances of CH3CN, HC3N, and HCN between our disk sample, protostellar envelopes, and solar system comets; this is suggestive of a robust nitrile chemistry with similar outcomes under a wide range of physical conditions.

  10. Structure of MoCN films deposited by cathodic arc evaporation

    Energy Technology Data Exchange (ETDEWEB)

    Gilewicz, A., E-mail: adam.gilewicz@tu.koszalin.pl [Koszalin University of Technology, Faculty of Technology and Education, Sniadeckich 2, 75-453 Koszalin (Poland); Jedrzejewski, R.; Kochmanska, A.E. [West Pomeranian University of Technology Szczecin, Faculty of Mechanical Engineering and Mechatronics, 19 Piastów Ave., 70-313 Szczecin (Poland); Warcholinski, B. [Koszalin University of Technology, Faculty of Technology and Education, Sniadeckich 2, 75-453 Koszalin (Poland)

    2015-02-27

    Molybdenum carbonitride (MoCN) coatings were deposited onto HS6-5-2 steel substrate using pure Mo targets in mixed acetylene and nitrogen atmosphere by cathodic arc evaporation. The structural properties of MoCN coatings with different carbon contents (as an effect of the C{sub 2}H{sub 2} flow rate) were investigated systematically. Phase and chemical composition evolution of the coatings were characterized both by the glancing angle of X-ray diffraction (XRD) and wavelength dispersive spectrometry, respectively. These analyses have been supplemented by estimates of grain sizes and stress in the coatings. The XRD results show that the increase in acetylene flow rate causes the formation of molybdenum carbide (MoC) hexagonal phase in the coatings, a reduction of grain size and an increase in internal stress. - Highlights: • MoN and MoCN coatings were deposited by cathodic arc evaporation in nitrogen atmosphere. • MoCN coatings were formed using different acetylene flow rates. • Phase composition evolution was observed. • Crystallite size and stress were calculated.

  11. Electrochemical studies on Li /K ion exchange behaviour in K4Fe(CN)

    Indian Academy of Sciences (India)

    based,24 sol-gel,17–21 and solid-state16 meth- ods. There are a .... Double potential step chronoamper- ometry was ... removal of moisture as well as water of crystallisa- tion and the .... active material, K4Fe(CN)6, carbon black and graphite.

  12. Electron paramagnetic resonance of K3Rh(CN)6 irradiated with electrons in KCl

    International Nuclear Information System (INIS)

    Vugman, N.V.

    1970-07-01

    Using a simple theory, it was estimated the electronic density of the diamagnetic complex Rh (CN) 3- 6 in a KCl lattice. The g// and g1 values were determined by EPR, and the experimental results fit the theoretical calculations. (M.W.O.) [pt

  13. Quantitative and sensitive analysis of CN molecules using laser induced low pressure He plasma

    Energy Technology Data Exchange (ETDEWEB)

    Pardede, Marincan [Department of Electrical Engineering, University of Pelita Harapan, 1100 M.H. Thamrin Boulevard, Lippo Village, Tangerang 15811 (Indonesia); Hedwig, Rinda [Department of Computer Engineering, Bina Nusantara University, 9 K.H. Syahdan, Jakarta 14810 (Indonesia); Abdulmadjid, Syahrun Nur; Lahna, Kurnia; Idris, Nasrullah; Ramli, Muliadi [Department of Physics, Faculty of Mathematics and Natural Sciences, Syiah Kuala University, Darussalam, Banda Aceh 23111, NAD (Indonesia); Jobiliong, Eric [Department of Industrial Engineering, University of Pelita Harapan, 1100 M.H. Thamrin Boulevard, Lippo Village, Tangerang 15811 (Indonesia); Suyanto, Hery [Department of Physics, Faculty of Mathematics and Natural Sciences, Udayana University, Kampus Bukit Jimbaran, Denpasar 80361, Bali (Indonesia); Marpaung, Alion Mangasi [Department of Physics, Faculty of Mathematics and Natural Sciences, Jakarta State University, 10 Rawamangun, Jakarta 13220 (Indonesia); Suliyanti, Maria Margaretha [Research Center for Physics, Indonesia Institute of Sciences, Kawasan Puspiptek, Serpong, Tangerang Selatan, 15314 Banten (Indonesia); Tjia, May On [Physics of Magnetism and Photonics Group, Faculty of Mathematics and Natural Sciences, Bandung Institute of Technology, 10 Ganesha, Bandung 40132 (Indonesia); Research Center of Maju Makmur Mandiri Foundation, 40/80 Srengseng Raya, Jakarta 11630 (Indonesia); Lie, Tjung Jie; Lie, Zener Sukra; Kurniawan, Davy Putra; Kurniawan, Koo Hendrik, E-mail: kurnia18@cbn.net.id [Research Center of Maju Makmur Mandiri Foundation, 40/80 Srengseng Raya, Jakarta 11630 (Indonesia); Kagawa, Kiichiro [Research Center of Maju Makmur Mandiri Foundation, 40/80 Srengseng Raya, Jakarta 11630 (Indonesia); Fukui Science Education Academy, Takagi Chuou 2 choume, Fukui 910-0804 (Japan)

    2015-03-21

    We report the results of experimental study on CN 388.3 nm and C I 247.8 nm emission characteristics using 40 mJ laser irradiation with He and N{sub 2} ambient gases. The results obtained with N{sub 2} ambient gas show undesirable interference effect between the native CN emission and the emission of CN molecules arising from the recombination of native C ablated from the sample with the N dissociated from the ambient gas. This problem is overcome by the use of He ambient gas at low pressure of 2 kPa, which also offers the additional advantages of cleaner and stronger emission lines. The result of applying this favorable experimental condition to emission spectrochemical measurement of milk sample having various protein concentrations is shown to yield a close to linear calibration curve with near zero extrapolated intercept. Additionally, a low detection limit of 5 μg/g is found in this experiment, making it potentially applicable for quantitative and sensitive CN analysis. The visibility of laser induced breakdown spectroscopy with low pressure He gas is also demonstrated by the result of its application to spectrochemical analysis of fossil samples. Furthermore, with the use of CO{sub 2} ambient gas at 600 Pa mimicking the Mars atmosphere, this technique also shows promising applications to exploration in Mars.

  14. Heat production in growing pigs calculated according to the RQ and CN methods

    DEFF Research Database (Denmark)

    Christensen, K; Chwalibog, André; Henckel, S

    1988-01-01

    1. Heat production, calculated according to the respiratory quotient methods, HE(RQ), and the carbon nitrogen balance method, HE(CN), was compared using the results from a total of 326 balance trials with 56 castrated male pigs fed different dietary composition and variable feed levels during...

  15. Spatial distributions of H, CN, and C2 in a diamond growing oxyacetylene flame

    NARCIS (Netherlands)

    Klein-Douwel, R.J.H.; Meulen, ter J.J.

    1998-01-01

    Two-dimensional laser-induced fluorescence (2D-LIF) measurements are applied to the chemical vapor deposition (CVD) of diamond by an oxyacetylene flame to visualize the distributions of atomic hydrogen, C2, and CN in the gas phase during diamond growth. Experiments are carried out in laminar flames

  16. Characterization of NCAM expression and function in BT4C and BT4Cn glioma cells

    DEFF Research Database (Denmark)

    Andersson, A M; Moran, N; Gaardsvoll, H

    1991-01-01

    The neural cell adhesion molecule, NCAM, plays an important role in cell-cell adhesion. Therefore, we have studied NCAM expression in the glioma cell lines BT4C and BT4Cn. We demonstrate that the 2 cell lines differ in their metastatic ability; while BT4C cells have a very low capacity for produc...

  17. Triosmium cluster compounds containing isocyanide and hydride ligands. Crystal and molecular structures of (μ-H)(H)Os3(CO)10(CN-t-C4H9) and (μ-H)2Os3(CO)9(CN-t-C4H9)

    International Nuclear Information System (INIS)

    Adams, R.D.; Golembski, N.M.

    1979-01-01

    The structures of the compounds (μ-H)(H)Os 3 (CO) 10 (CN-t-C 4 H 9 ) and (μ-H) 2 Os 3 (CO) 9 (CN-t-C 4 H 9 ) have been revealed by x-ray crystallographic techniques. For (μ-H)(H)Os 3 (CO) 10 (CN-t-C 4 H 9 ): a = 9.064 (3), b = 12.225 (3), c = 20.364 (4) A; β = 98.73 (3) 0 ; space group P2 1 /c[C/sub 2h/ 5 ], No. 14; Z = 4; d/sub calcd/ = 2.79 g cm -3 . This compound contains a triangular cluster of three osmium atoms; Os(1)--Os(2) = 2.930 (1) A, Os(1)--Os(3) = 2.876 (1) A, and Os(2)--Os(3) = 3.000 (1) A. There are ten linear terminal carbonyl groups and one linear terminal isocyanide ligand which occupies an axial coordination site. The hydrogen atoms were not observed crystallographically, but their positions are strongly inferred from considerations of molecular geometry. For (μ-H) 2 Os 3 (CO) 9 (CN-t-C 4 H 9 ): a = 15.220 (8), b = 12.093 (6), c = 23.454 (5) A; space group Pbcn [D/sub 2h/ 14 ], No. 60; Z = 8; d/sub calcd/ = 2.79 g cm -3 . The compound is analogous to the parent carbonyl (μ-H) 2 Os 3 (CO) 10 and has two normal and one short osmium--osmium bonds: Os(1)--Os(2) = 2.827 (1) A, Os(1)--Os(3) = 2.828 (1) A, Os(2)--Os(3) = 2.691 (1) A. The isocyanide ligand resides in an equatorial coordination site on osmium Os(2). The hydrogen atoms were not observed but are believed to occupy bridging positions as in the parent carbonyl complex. 2 figures, 7 tables

  18. The hierarchically organized splitting of chromosome bands into sub-bands analyzed by multicolor banding (MCB).

    Science.gov (United States)

    Lehrer, H; Weise, A; Michel, S; Starke, H; Mrasek, K; Heller, A; Kuechler, A; Claussen, U; Liehr, T

    2004-01-01

    To clarify the nature of chromosome sub-bands in more detail, the multicolor banding (MCB) probe-set for chromosome 5 was hybridized to normal metaphase spreads of GTG band levels at approximately 850, approximately 550, approximately 400 and approximately 300. It could be observed that as the chromosomes became shorter, more of the initial 39 MCB pseudo-colors disappeared, ending with 18 MCB pseudo-colored bands at the approximately 300-band level. The hierarchically organized splitting of bands into sub-bands was analyzed by comparing the disappearance or appearance of pseudo-color bands of the four different band levels. The regions to split first are telomere-near, centromere-near and in 5q23-->q31, followed by 5p15, 5p14, and all GTG dark bands in 5q apart from 5q12 and 5q32 and finalized by sub-band building in 5p15.2, 5q21.2-->q21.3, 5q23.1 and 5q34. The direction of band splitting towards the centromere or the telomere could be assigned to each band separately. Pseudo-colors assigned to GTG-light bands were resistant to band splitting. These observations are in concordance with the recently proposed concept of chromosome region-specific protein swelling. Copyright 2003 S. Karger AG, Basel

  19. Identifying chiral bands in real nuclei

    International Nuclear Information System (INIS)

    Shirinda, O.; Lawrie, E.A.

    2012-01-01

    The application of the presently used fingerprints of chiral bands (originally derived for strongly broken chirality) is investigated for real chiral systems. In particular the chiral fingerprints concerning the B(M1) staggering patterns and the energy staggering are studied. It is found that both fingerprints show considerable changes for real chiral systems, a behaviour that creates a significant risk for misinterpretation of the experimental data and can lead to a failure to identify real chiral systems. (orig.)

  20. Strong-interaction nonuniversality

    International Nuclear Information System (INIS)

    Volkas, R.R.; Foot, R.; He, X.; Joshi, G.C.

    1989-01-01

    The universal QCD color theory is extended to an SU(3) 1 direct product SU(3) 2 direct product SU(3) 3 gauge theory, where quarks of the ith generation transform as triplets under SU(3)/sub i/ and singlets under the other two factors. The usual color group is then identified with the diagonal subgroup, which remains exact after symmetry breaking. The gauge bosons associated with the 16 broken generators then form two massive octets under ordinary color. The interactions between quarks and these heavy gluonlike particles are explicitly nonuniversal and thus an exploration of their physical implications allows us to shed light on the fundamental issue of strong-interaction universality. Nonuniversality and weak flavor mixing are shown to generate heavy-gluon-induced flavor-changing neutral currents. The phenomenology of these processes is studied, as they provide the major experimental constraint on the extended theory. Three symmetry-breaking scenarios are presented. The first has color breaking occurring at the weak scale, while the second and third divorce the two scales. The third model has the interesting feature of radiatively induced off-diagonal Kobayashi-Maskawa matrix elements

  1. John Strong (1941 - 2006)

    CERN Multimedia

    Wickens, F

    Our friend and colleague John Strong was cruelly taken from us by a brain tumour on Monday 31st July, a few days before his 65th birthday John started his career working with a group from Westfield College, under the leadership of Ted Bellamy. He obtained his PhD and spent the early part of his career on experiments at Rutherford Appleton Laboratory (RAL), but after the early 1970s his research was focussed on experiments in CERN. Over the years he made a number of notable contributions to experiments in CERN: The Omega spectrometer adopted a system John had originally developed for experiments at RAL using vidicon cameras to record the sparks in the spark chambers; He contributed to the success of NA1 and NA7, where he became heavily involved in the electronic trigger systems; He was responsible for the second level trigger system for the ALEPH detector and spent five years leading a team that designed and built the system, which ran for twelve years with only minor interventions. Following ALEPH he tur...

  2. Stirring Strongly Coupled Plasma

    CERN Document Server

    Fadafan, Kazem Bitaghsir; Rajagopal, Krishna; Wiedemann, Urs Achim

    2009-01-01

    We determine the energy it takes to move a test quark along a circle of radius L with angular frequency w through the strongly coupled plasma of N=4 supersymmetric Yang-Mills (SYM) theory. We find that for most values of L and w the energy deposited by stirring the plasma in this way is governed either by the drag force acting on a test quark moving through the plasma in a straight line with speed v=Lw or by the energy radiated by a quark in circular motion in the absence of any plasma, whichever is larger. There is a continuous crossover from the drag-dominated regime to the radiation-dominated regime. In the crossover regime we find evidence for significant destructive interference between energy loss due to drag and that due to radiation as if in vacuum. The rotating quark thus serves as a model system in which the relative strength of, and interplay between, two different mechanisms of parton energy loss is accessible via a controlled classical gravity calculation. We close by speculating on the implicati...

  3. EDF-1 downregulates the CaM/Cn/NFAT signaling pathway during adipogenesis

    International Nuclear Information System (INIS)

    López-Victorio, Carlos J.; Velez-delValle, Cristina; Beltrán-Langarica, Alicia; Kuri-Harcuch, Walid

    2013-01-01

    Highlights: ► EDF-1 participates early adipogenesis in 3T3F442A cells induced with Staurosporine/Dexamethasone. ► EDF-1 associates with CaM and Cn, most likely inactivating Cn. ► EDF-1/CaM complex seems to prevent NFATc1 activation by Cn. ► EDF-1 regulates the Cn/CaM/NFATc1 pathway during adipogenesis. ► EDF-1 may regulate the activation of Cn through a complex formation with CaM. - Abstract: The endothelial differentiation factor-1 (EDF-1) is a calmodulin binding protein that regulates calmodulin-dependent enzymes. In endothelial cells, this factor can form a protein complex with calmodulin. We analyzed the relationship between this factor and the members of calmodulin/calcineurin/nuclear factor of activated T-cells (NFAT) signaling pathway during adipogenesis of 3T3-F442A cells. We found that the expression of edf1 is upregulated during early adipogenesis, whereas that of calcineurin gene is lowered, suggesting that this pathway should be downregulated to allow for adipogenesis to occur. We also found that EDF-1 associates with calmodulin and calcineurin, most likely inactivating calcineurin. Our results showed that EDF-1 inactivates the calmodulin/calcineurin/NFAT pathway via sequestration of calmodulin, during early adipogenesis, and we propose a mechanism that negatively regulates the activation of calcineurin through a complex formation between EDF-1 and calmodulin. This finding raises the possibility that modulating this pathway might offer some alternatives to regulate adipose biology

  4. Characterization of thick and thin film SiCN for pressure sensing at high temperatures.

    Science.gov (United States)

    Leo, Alfin; Andronenko, Sergey; Stiharu, Ion; Bhat, Rama B

    2010-01-01

    Pressure measurement in high temperature environments is important in many applications to provide valuable information for performance studies. Information on pressure patterns is highly desirable for improving performance, condition monitoring and accurate prediction of the remaining life of systems that operate in extremely high temperature environments, such as gas turbine engines. A number of technologies have been recently investigated, however these technologies target specific applications and they are limited by the maximum operating temperature. Thick and thin films of SiCN can withstand high temperatures. SiCN is a polymer-derived ceramic with liquid phase polymer as its starting material. This provides the advantage that it can be molded to any shape. CERASET™ also yields itself for photolithography, with the addition of photo initiator 2, 2-Dimethoxy-2-phenyl-acetophenone (DMPA), thereby enabling photolithographical patterning of the pre-ceramic polymer using UV lithography. SiCN fabrication includes thermosetting, crosslinking and pyrolysis. The technology is still under investigation for stability and improved performance. This work presents the preparation of SiCN films to be used as the body of a sensor for pressure measurements in high temperature environments. The sensor employs the phenomenon of drag effect. The pressure sensor consists of a slender sensitive element and a thick blocking element. The dimensions and thickness of the films depend on the intended application of the sensors. Fabrication methods of SiCN ceramics both as thin (about 40-60 μm) and thick (about 2-3 mm) films for high temperature applications are discussed. In addition, the influence of thermosetting and annealing processes on mechanical properties is investigated.

  5. Characterization of Thick and Thin Film SiCN for Pressure Sensing at High Temperatures

    Directory of Open Access Journals (Sweden)

    Rama B. Bhat

    2010-02-01

    Full Text Available Pressure measurement in high temperature environments is important in many applications to provide valuable information for performance studies. Information on pressure patterns is highly desirable for improving performance, condition monitoring and accurate prediction of the remaining life of systems that operate in extremely high temperature environments, such as gas turbine engines. A number of technologies have been recently investigated, however these technologies target specific applications and they are limited by the maximum operating temperature. Thick and thin films of SiCN can withstand high temperatures. SiCN is a polymer-derived ceramic with liquid phase polymer as its starting material. This provides the advantage that it can be molded to any shape. CERASET™ also yields itself for photolithography, with the addition of photo initiator 2, 2-Dimethoxy-2-phenyl-acetophenone (DMPA, thereby enabling photolithographical patterning of the pre-ceramic polymer using UV lithography. SiCN fabrication includes thermosetting, crosslinking and pyrolysis. The technology is still under investigation for stability and improved performance. This work presents the preparation of SiCN films to be used as the body of a sensor for pressure measurements in high temperature environments. The sensor employs the phenomenon of drag effect. The pressure sensor consists of a slender sensitive element and a thick blocking element. The dimensions and thickness of the films depend on the intended application of the sensors. Fabrication methods of SiCN ceramics both as thin (about 40–60 µm and thick (about 2–3 mm films for high temperature applications are discussed. In addition, the influence of thermosetting and annealing processes on mechanical properties is investigated.

  6. Isolation and partial characterization of antimicrobial compounds from a new strain Streptomyces sp. CN207

    International Nuclear Information System (INIS)

    Slama, Nedra; Lazim, Hadeer; Barkallah, Insaf; Limam, Ferid

    2008-01-01

    A distinct streptomyces strains were isolated from Tunisian soil. the isolate designed CN207, was assigned to the genus streptomyces on the basis of morphological and chemotaxonomic criteria. A 16S rDNA sequence of the isolate was determined. Streptomyces sp CN207 secreted large amount antibiotic against gram positive bacteria, gram negative bacteria, yeast and fungi on his barley (HB) medium. (HB) medium was found to be suitable substrate of the medium for CN207 production. Maximum yield of CN207 product (700 mg/ml) after optimize fermentation process. Bioactive molecules from strain CN207 were extracted with ethyl acetate and analyzed by PTLC using silica gel plates.The separated compounds were visualiszed under UV at 254 nm and the active spots were detected by bioautography on silica gel plates using salmonella thyphimurium NRRL B4420 and Staphylococcus aureus CDC 103 as indicator microorganisms. The crude extract (8.36 g) was fractionated on Sep-pack column (C18 cartridge) and elution was performed using a discontinue gradient of methanol-water. Two active fractions eluted by 20% and 40% of methanol were obtained. The bioactive compounds were separated by preparative high performance liquid chromatography (HPLC) on a C18 reversed phase column and eluted with a linear gradient of acetonitrile -water in presence of 0.1% formic acid. The peaks were collected separately, concentrated and bioassayed against the routine indicator microorganisms. The absorption spectrum of the active molecules was determined with a shimadzu UV-160 a spectrophotometer. Determination of the chemical structure of these compounds on the basis on their IR, COSY and H 1: C13 is in progress

  7. EDF-1 downregulates the CaM/Cn/NFAT signaling pathway during adipogenesis

    Energy Technology Data Exchange (ETDEWEB)

    López-Victorio, Carlos J.; Velez-delValle, Cristina; Beltrán-Langarica, Alicia [Department of Cell Biology, Center for Research and Advanced Studies-IPN, Apdo. Postal 14-740, México City 07000 (Mexico); Kuri-Harcuch, Walid, E-mail: walidkuri@gmail.com [Department of Cell Biology, Center for Research and Advanced Studies-IPN, Apdo. Postal 14-740, México City 07000 (Mexico)

    2013-03-01

    Highlights: ► EDF-1 participates early adipogenesis in 3T3F442A cells induced with Staurosporine/Dexamethasone. ► EDF-1 associates with CaM and Cn, most likely inactivating Cn. ► EDF-1/CaM complex seems to prevent NFATc1 activation by Cn. ► EDF-1 regulates the Cn/CaM/NFATc1 pathway during adipogenesis. ► EDF-1 may regulate the activation of Cn through a complex formation with CaM. - Abstract: The endothelial differentiation factor-1 (EDF-1) is a calmodulin binding protein that regulates calmodulin-dependent enzymes. In endothelial cells, this factor can form a protein complex with calmodulin. We analyzed the relationship between this factor and the members of calmodulin/calcineurin/nuclear factor of activated T-cells (NFAT) signaling pathway during adipogenesis of 3T3-F442A cells. We found that the expression of edf1 is upregulated during early adipogenesis, whereas that of calcineurin gene is lowered, suggesting that this pathway should be downregulated to allow for adipogenesis to occur. We also found that EDF-1 associates with calmodulin and calcineurin, most likely inactivating calcineurin. Our results showed that EDF-1 inactivates the calmodulin/calcineurin/NFAT pathway via sequestration of calmodulin, during early adipogenesis, and we propose a mechanism that negatively regulates the activation of calcineurin through a complex formation between EDF-1 and calmodulin. This finding raises the possibility that modulating this pathway might offer some alternatives to regulate adipose biology.

  8. Complete Genome Sequence of Bacillus velezensis CN026 Exhibiting Antagonistic Activity against Gram-Negative Foodborne Pathogens.

    Science.gov (United States)

    Nannan, Catherine; Gillis, Annika; Caulier, Simon; Mahillon, Jacques

    2018-01-25

    We report here the complete genome sequence of Bacillus velezensis strain CN026, a member of the B. subtilis group, which is known for its many industrial applications. The genome contains 3,995,812 bp and displays six gene clusters potentially involved in strain CN026's activity against Gram-negative foodborne pathogens. Copyright © 2018 Nannan et al.

  9. Complete Genome Sequence of Bacillus velezensis CN026 Exhibiting Antagonistic Activity against Gram-Negative Foodborne Pathogens

    OpenAIRE

    Nannan, Catherine; Gillis, Annika; Caulier, Simon; Mahillon, Jacques

    2018-01-01

    ABSTRACT We report here the complete genome sequence of Bacillus velezensis strain CN026, a member of the B. subtilis group, which is known for its many industrial applications. The genome contains 3,995,812 bp and displays six gene clusters potentially involved in strain CN026’s activity against Gram-negative foodborne pathogens.

  10. 76 FR 28727 - Child Nutrition (CN) Labeling Program; Request for Extension and Revision of a Currently Approved...

    Science.gov (United States)

    2011-05-18

    ... (CN) Labeling Program; Request for Extension and Revision of a Currently Approved Information... INFORMATION: Title: Child Nutrition Labeling Program. OMB Number: 0581-0261 . Expiration Date of Approval: 3... collection. Abstract: The Child Nutrition (CN) Labeling Program is a voluntary technical assistance service...

  11. Noise exposure in marching bands

    Science.gov (United States)

    Keefe, Joseph

    2005-09-01

    Previous studies involving orchestras have shown that music ensembles can produce hazardous noise levels. There are no similar data for marching bands and pep bands. In order to evaluate the noise levels produced by marching and pep bands, 1/3-octave-band sound-pressure levels were measured while these groups rehearsed and performed. Data were collected while marching with the bands to ensure a realistic environment. Comparing these data to OSHA and NIOSH criteria, marching and pep band exposures often exceed safe values. For typical exposures, OSHA doses range from 11% to 295%, while NIOSH doses range from 35% to 3055%. Exposures that would be considered hazardous in the workplace are common in marching and pep bands; students and band directors should take steps to recognize the risk posed by various instruments and various locations, and should implement hearing conservation efforts.

  12. Semiconductors bonds and bands

    CERN Document Server

    Ferry, David K

    2013-01-01

    As we settle into this second decade of the twenty-first century, it is evident that the advances in micro-electronics have truly revolutionized our day-to-day lifestyle. The technology is built upon semiconductors, materials in which the band gap has been engineered for special values suitable to the particular application. This book, written specifically for a one semester course for graduate students, provides a thorough understanding of the key solid state physics of semiconductors. It describes how quantum mechanics gives semiconductors unique properties that enabled the micro-electronics revolution, and sustain the ever-growing importance of this revolution.

  13. Anomalous electromagnetically induced transparency in photonic-band-gap materials

    International Nuclear Information System (INIS)

    Singh, Mahi R.

    2004-01-01

    The phenomenon of electromagnetically induced transparency has been studied when a four-level atom is located in a photonic band gap material. Quantum interference is introduced by driving the two upper levels of the atom with a strong pump laser field. The top level and one of the ground levels are coupled by a weak probe laser field and absorption takes place between these two states. The susceptibility due to the absorption for this transition has been calculated by using the master equation method in linear response theory. Numerical simulations are performed for the real and imaginary parts of the susceptibility for a photonic band gap material whose gap-midgap ratio is 21%. It is found that when resonance frequencies lie within the band, the medium becomes transparent under the action of the strong pump laser field. More interesting results are found when one of the resonance frequencies lies at the band edge and within the band gap. When the resonance frequency lies at the band edge, the medium becomes nontransparent even under a strong pump laser field. On the other hand, when the resonance frequency lies within the band gap, the medium becomes transparent even under a weak pump laser field. In summary, we found that the medium can be transformed from the transparent state to the nontransparent state just by changing the location of the resonance frequency. We call these two effects anomalous electromagnetically induced transparency

  14. First Results of the Sideband-Separating Mixer for ALMA Band 9 Upgrade

    NARCIS (Netherlands)

    Khudchenko, Andrey; Hesper, Ronald; Baryshev, Andrey; Mena, F. Patricio; Gerlofma, Gerrit; Zijlstra, Tony; Klapwijk, Teun M.; Kooi, Jacob W.; Spaans, Marco

    2011-01-01

    Last year, the design and implementation details of a new modular sideband-separating mixer block, intended as an upgrade for the current single-ended ALMA Band 9 mixers, were presented at this conference. In high-frequency observation bands like ALMA Band 9 (600-720 GHz), which is strongly

  15. Retrieval of Wind Speed Using an L-band Synthetic Aperture Radar

    DEFF Research Database (Denmark)

    Monaldo, Frank M.; Thompson, Donald R.; Badger, Merete

    2007-01-01

    Retrieval of wind speed using L-band synthetic aperture radar (SAR) is both an old and new endeavor. Although the Seasat L-band SAR in 1978 was not well calibrated, early results indicated a strong relationship between observed SAR image intensity and wind speed. The JERS-1 L-band SAR had limited...

  16. Two different one-dimensional structural motifs in [catena-{Cu(tacn)}2Pd(CN)4]Br2.[catena-Cu(tacn)Pd(CN)4]2.H2O (tacn is 1,4,7-triazacyclononane).

    Science.gov (United States)

    Kuchár, Juraj; Cernák, Juraj

    2009-07-01

    The title compound, catena-poly[[bis[(triazacyclononane-kappa(3)N,N',N'')copper(II)]-di-mu-cyanido-kappa(4)N:C-palladate(II)-di-mu-cyanido-kappa(4)C:N] dibromide bis[[(triazacyclononane-kappa(3)N,N',N'')copper(II)]-mu-cyanido-kappa(2)N:C-[dicyanidopalladate(II)]-mu-cyanido-kappa(2)C:N] monohydrate], {[Cu(2)Pd(CN)(4)(C(6)H(15)N(3))(2)]Br(2).[Cu(2)Pd(2)(CN)(8)(C(6)H(15)N(3))(2)].H(2)O}(n), (I), was isolated from an aqueous solution containing tacn.3HBr (tacn is 1,4,7-triazacyclononane), Cu(2+) and tetracyanidopalladate(2-) anions. The crystal structure of (I) is essentially ionic and built up of 2,2-electroneutral chains, viz. [Cu(tacn)(NC)-Pd(CN)(2)-(CN)-], positively charged 2,4-ribbons exhibiting the composition {[Cu(tacn)(NC)(2)-Pd(CN)(2)-Cu(tacn)](2n+)}(n), bromide anions and one disordered water molecule of crystallization. The O atom of the water molecule occupies two unique crystallographic positions, one on a centre of symmetry, which is half occupied, and the other in a general position with one-quarter occupancy. One of the tacn ligands also exhibits disorder. The formation of two different types of one-dimensional structural motif within the same structure is a unique feature of this compound.

  17. Towards TDDFT for Strongly Correlated Materials

    Directory of Open Access Journals (Sweden)

    Shree Ram Acharya

    2016-09-01

    Full Text Available We present some details of our recently-proposed Time-Dependent Density-Functional Theory (TDDFT for strongly-correlated materials in which the exchange-correlation (XC kernel is derived from the charge susceptibility obtained using Dynamical Mean-Field Theory (the TDDFT + DMFT approach. We proceed with deriving the expression for the XC kernel for the one-band Hubbard model by solving DMFT equations via two approaches, the Hirsch–Fye Quantum Monte Carlo (HF-QMC and an approximate low-cost perturbation theory approach, and demonstrate that the latter gives results that are comparable to the exact HF-QMC solution. Furthermore, through a variety of applications, we propose a simple analytical formula for the XC kernel. Additionally, we use the exact and approximate kernels to examine the nonhomogeneous ultrafast response of two systems: a one-band Hubbard model and a Mott insulator YTiO3. We show that the frequency dependence of the kernel, i.e., memory effects, is important for dynamics at the femtosecond timescale. We also conclude that strong correlations lead to the presence of beats in the time-dependent electric conductivity in YTiO3, a feature that could be tested experimentally and that could help validate the few approximations used in our formulation. We conclude by proposing an algorithm for the generalization of the theory to non-linear response.

  18. Degenerate band edge laser

    Science.gov (United States)

    Veysi, Mehdi; Othman, Mohamed A. K.; Figotin, Alexander; Capolino, Filippo

    2018-05-01

    We propose a class of lasers based on a fourth-order exceptional point of degeneracy (EPD) referred to as the degenerate band edge (DBE). EPDs have been found in parity-time-symmetric photonic structures that require loss and/or gain; here we show that the DBE is a different kind of EPD since it occurs in periodic structures that are lossless and gainless. Because of this property, a small level of gain is sufficient to induce single-frequency lasing based on a synchronous operation of four degenerate Floquet-Bloch eigenwaves. This lasing scheme constitutes a light-matter interaction mechanism that leads also to a unique scaling law of the laser threshold with the inverse of the fifth power of the laser-cavity length. The DBE laser has the lowest lasing threshold in comparison to a regular band edge laser and to a conventional laser in cavities with the same loaded quality (Q ) factor and length. In particular, even without mirror reflectors the DBE laser exhibits a lasing threshold which is an order of magnitude lower than that of a uniform cavity laser of the same length and with very high mirror reflectivity. Importantly, this novel DBE lasing regime enforces mode selectivity and coherent single-frequency operation even for pumping rates well beyond the lasing threshold, in contrast to the multifrequency nature of conventional uniform cavity lasers.

  19. Photonic band structures in one-dimensional photonic crystals containing Dirac materials

    International Nuclear Information System (INIS)

    Wang, Lin; Wang, Li-Gang

    2015-01-01

    We have investigated the band structures of one-dimensional photonic crystals (1DPCs) composed of Dirac materials and ordinary dielectric media. It is found that there exist an omnidirectional passing band and a kind of special band, which result from the interaction of the evanescent and propagating waves. Due to the interface effect and strong dispersion, the electromagnetic fields inside the special bands are strongly enhanced. It is also shown that the properties of these bands are invariant upon the lattice constant but sensitive to the resonant conditions

  20. In Situ Electrochemical SFG/DFG Study of CN and Nitrile Adsorption at Au from 1-Butyl-1-methyl-pyrrolidinium Bis(trifluoromethylsulfonyl Amide Ionic Liquid ([BMP][TFSA] Containing 4-{2-[1-(2-Cyanoethyl-1,2,3,4-tetrahydroquinolin-6-yl]diazenyl} Benzonitrile (CTDB and K[Au(CN2

    Directory of Open Access Journals (Sweden)

    Benedetto Bozzini

    2012-06-01

    Full Text Available In this paper we report an in situ electrochemical Sum-/Difference Frequency Generation (SFG/DFG spectroscopy investigation of the adsorption of nitrile and CN from the ionic liquid 1-butyl-1-methyl-pyrrolidinium bis(trifluoromethylsulfonyl amide ([BMP][TFSA] containing 4-{2-[1-(2-cyanoethyl-1,2,3,4-tetrahydroquinolin-6-yl]- diazenyl}benzonitrile (CTDB at Au electrodes in the absence and in the presence of the Au-electrodeposition process from K[Au(CN2]. The adsorption of nitrile and its coadsorption with CN resulting either from the cathodic decomposition of the dye or from ligand release from the Au(I cyanocomplex yield potential-dependent single or double SFG bands in the range 2,125–2,140 cm1, exhibiting Stark tuning values of ca. 3 and 1 cm1 V1 in the absence and presence of electrodeposition, respectively. The low Stark tuning found during electrodeposition correlates with the cathodic inhibiting effect of CTDB, giving rise to its levelling properties. The essential insensitivity of the other DFG parameters to the electrodeposition process is due to the growth of smooth Au.

  1. Sorption Mechanisms of Cesium on Cu II2Fe II(CN) 6and Cu II3[Fe III(CN) 6] 2Hexacyanoferrates and Their Relation to the Crystalline Structure

    Science.gov (United States)

    Ayrault, S.; Jimenez, B.; Garnier, E.; Fedoroff, M.; Jones, D. J.; Loos-Neskovic, C.

    1998-12-01

    CuII2FeII(CN)6·xH2O and CuII3[FeIII(CN)6]2·xH2O can be prepared with reproducible chemical compositions and structures after careful washing. They have cubicFmoverline3mstructures with iron vacancies. In CuII2FeII(CN)6, copper occupies two different sites: Cu1 in position 4blinked to Fe through the CN groups, and Cu2 not linked to the CN groups and partially occupying the interstitial 24epositions. The second type of site is not present in CuII3[FeIII(CN)6]2. Sorption kinetics and isotherms were determined for cesium on both hexacyanoferrates by batch experiments. On CuII3[FeIII(CN)6]2, the maximum uptake is only 0.073 Cs/Fe (at./at.). On CuII2FeII(CN)6, the uptake reaches 1.5 Cs/Fe. The sorption kinetics include at least two steps: at1/2variation until approximately 72 h and then a slow evolution studied up to 6 months. The sorption mechanism is complex. The main process seems to be diffusion of ion pairs, followed by a reorganization of the solid, resulting in one or more new solid phases. The presence of the Cu2 site seems to play a favorable role in the sorption. Owing to its good midterm stability and the first rapid step of exchange, CuII2FeII(CN)6·xH2O seems to be one of the most promising compounds for the recovery of cesium from nuclear liquid wastes.

  2. Structure and property relationships of amorphous CN sub x a joint experimental and theoretical study

    CERN Document Server

    Santos, M C D

    2000-01-01

    Amorphous CN sub x and CN sub x :H have been prepared by the ion beam assisted deposition technique. Samples were characterized through X-ray and UV photoemission, IR absorption and Raman spectroscopies. These spectra have been interpreted with the aid of quantum chemical calculations based upon the Hartree-Fock theory on several molecular models. The understanding of the electronic and structural properties of the amorphous alloy as a function of nitrogen content could help in the task of synthesizing the metastable silicon-nitride like-phase beta-C sub 3 N sub 4 , a solid which has been predicted to be as hard as diamond. The physical picture emerging from the present study helps to clarify the difficulties in obtaining the crystalline phase of the material, suggesting new experimental directions for syntheses.

  3. Applications of Palladium-Catalyzed C-N Cross-Coupling Reactions.

    Science.gov (United States)

    Ruiz-Castillo, Paula; Buchwald, Stephen L

    2016-10-12

    Pd-catalyzed cross-coupling reactions that form C-N bonds have become useful methods to synthesize anilines and aniline derivatives, an important class of compounds throughout chemical research. A key factor in the widespread adoption of these methods has been the continued development of reliable and versatile catalysts that function under operationally simple, user-friendly conditions. This review provides an overview of Pd-catalyzed N-arylation reactions found in both basic and applied chemical research from 2008 to the present. Selected examples of C-N cross-coupling reactions between nine classes of nitrogen-based coupling partners and (pseudo)aryl halides are described for the synthesis of heterocycles, medicinally relevant compounds, natural products, organic materials, and catalysts.

  4. A density functional study of structures and stability of SinCN clusters

    International Nuclear Information System (INIS)

    Gai Zhigang; Yang Li; Zhao Jie; Chu Shibo

    2011-01-01

    In this paper, density functional theory (DFT) B3LYP method with 6-311G * basis set has been used to investigate geometric configurations, vibrational frequencies and ground state energies of Si n CN (n = 2 ∼ 6) clusters. The energies and spin multiplicities of ground states and substable states have been discussed, respectively. Harmonic frequencies and infrared spectra intensity for these clusters are given in order to aid in the characterization of the stable structures. The results show that the zero point energy (ZPE), thermocapacity and entropies are nearly in proportion to increased n, whose average enhancement are 0.80 kcal/mol, 5.20 cal/mol · K and 12.72 cal/ mol · K, respectively. The stability of Si n CN (n = 2 ∼ 6) clusters with even n are greater than that with odd n. (authors)

  5. The Beckman-Quarles theorem for continuous mappings from R^n to C^n

    OpenAIRE

    Tyszka, Apoloniusz

    2002-01-01

    Let \\phi((x_1,...,x_n),(y_1,...,y_n))=(x_1-y_1)^2+...+(x_n-y_n)^2. We say that f:R^n -> C^n preserves distance d>=0 if for each x,y \\in R^n \\phi(x,y)=d^2 implies \\phi(f(x),f(y))=d^2. We prove that if x,y \\in R^n (n>=3) and |x-y|=(\\sqrt{2+2/n})^k \\cdot (2/n)^l (k,l are non-negative integers) then there exists a finite set {x,y} \\subseteq S(x,y) \\subseteq R^n such that each unit-distance preserving mapping from S(x,y) to C^n preserves the distance between x and y. It implies that each continuou...

  6. Scaling analysis of [Fe(pyrazole)4]2[Nb(CN)8] molecular magnet

    International Nuclear Information System (INIS)

    Konieczny, P.; Pełka, R.; Zieliński, P.M.; Pratt, F.L.; Pinkowicz, D.; Sieklucka, B.; Wasiutyński, T.

    2013-01-01

    The critical behaviour of the three dimensional (3D) molecular magnet {[Fe II (pirazol) 4 ] 2 [Nb IV (CN) 8 ]·4H 2 O} n has been studied with the use of experimental techniques such as ac magnetometry and zero field μSR spectroscopy. The sample orders magnetically below T c =7.8 K. The measurements allowed to determine static exponents β, γ, and the dynamic exponent w. The resulting exponent values indicate that the studied system belongs to the universality class of the 3D Heisenberg model. - Highlights: • The critical behaviour of {[Fe II (pirazol) 4 ] 2 [Nb IV (CN) 8 ]∙4H 2 O} n has been studied. • Critical exponents β, γ, and w were obtained from ac magnetometry and ZF µSR data. • All obtained values of critical exponents are close to the 3D Heisenberg model

  7. Electric dipole ordering in alkali-cyanides: NaCN and KCN

    International Nuclear Information System (INIS)

    Koiller, B.; Davidovich, M.A.; Carmo, L.C.S. do; Luety, F.

    1983-01-01

    A simple model for the low temperature electrically ordered state of NaCN and KCN is presented. The model takes into account electric dipole dressing effects which include cationic displacements determined experimentally. The ground state structure and the calculated values for the local electric fields are in fair agreement with experimental results. A parametrization for the elastic potencial confirms the plausibility of these model. (Author) [pt

  8. C-N bond cleavage of anilines by a (salen)ruthenium(VI) nitrido complex.

    Science.gov (United States)

    Man, Wai-Lun; Xie, Jianhui; Pan, Yi; Lam, William W Y; Kwong, Hoi-Ki; Ip, Kwok-Wa; Yiu, Shek-Man; Lau, Kai-Chung; Lau, Tai-Chu

    2013-04-17

    We report experimental and computational studies of the facile oxidative C-N bond cleavage of anilines by a (salen)ruthenium(VI) nitrido complex. We provide evidence that the initial step involves nucleophilic attack of aniline at the nitrido ligand of the ruthenium complex, which is followed by proton and electron transfer to afford a (salen)ruthenium(II) diazonium intermediate. This intermediate then undergoes unimolecular decomposition to generate benzene and N2.

  9. Optimal C:N ratio for the production of red pigments by Monascus ruber.

    Science.gov (United States)

    Said, Farhan M; Brooks, John; Chisti, Yusuf

    2014-09-01

    The carbon-to-nitrogen (C:N) ratio in the biomass of microfungi tends to be quite different (e.g. 10-15) compared with the C:N ratio in the red pigments (e.g. >20) of the fungus Monascus ruber. Therefore, determining an optimal C:N ratio in the culture medium for maximizing the production of the pigments is important. A culture medium composition is established for maximizing the production of the red pigment by the fungus M. ruber ICMP 15220 in submerged culture. The highest volumetric productivity of the red pigment was 0.023 AU L(-1) h(-1) in a batch culture (30 °C, initial pH of 6.5) with a defined medium of the following composition (g L(-1)): glucose (10), monosodium glutamate (MSG) (10), MgSO4·7H2O (0.5), KH2PO4 (5), K2HPO4 (5), ZnSO4·7H2O (0.01), FeSO4·7H2O (0.01), CaCl2 (0.1), MnSO4·H2O (0.03). This medium formulation had a C:N mole ratio of 9:1. Under these conditions, the specific growth rate of the fungus was 0.043 h(-1) and the peak biomass concentration was 6.7 g L(-1) in a 7-day culture. The biomass specific productivity of the red pigment was 1.06 AU g(-1) h(-1). The best nitrogen source proved to be MSG although four other inorganic nitrogen sources were evaluated.

  10. Beyond the SCS-CN method: A theoretical framework for spatially lumped rainfall-runoff response

    Science.gov (United States)

    Bartlett, M. S.; Parolari, A. J.; McDonnell, J. J.; Porporato, A.

    2016-06-01

    Since its introduction in 1954, the Soil Conservation Service curve number (SCS-CN) method has become the standard tool, in practice, for estimating an event-based rainfall-runoff response. However, because of its empirical origins, the SCS-CN method is restricted to certain geographic regions and land use types. Moreover, it does not describe the spatial variability of runoff. To move beyond these limitations, we present a new theoretical framework for spatially lumped, event-based rainfall-runoff modeling. In this framework, we describe the spatially lumped runoff model as a point description of runoff that is upscaled to a watershed area based on probability distributions that are representative of watershed heterogeneities. The framework accommodates different runoff concepts and distributions of heterogeneities, and in doing so, it provides an implicit spatial description of runoff variability. Heterogeneity in storage capacity and soil moisture are the basis for upscaling a point runoff response and linking ecohydrological processes to runoff modeling. For the framework, we consider two different runoff responses for fractions of the watershed area: "prethreshold" and "threshold-excess" runoff. These occur before and after infiltration exceeds a storage capacity threshold. Our application of the framework results in a new model (called SCS-CNx) that extends the SCS-CN method with the prethreshold and threshold-excess runoff mechanisms and an implicit spatial description of runoff. We show proof of concept in four forested watersheds and further that the resulting model may better represent geographic regions and site types that previously have been beyond the scope of the traditional SCS-CN method.

  11. Regional Calibration of SCS-CN L-THIA Model: Application for Ungauged Basins

    Directory of Open Access Journals (Sweden)

    Ji-Hong Jeon

    2014-05-01

    Full Text Available Estimating surface runoff for ungauged watershed is an important issue. The Soil Conservation Service Curve Number (SCS-CN method developed from long-term experimental data is widely used to estimate surface runoff from gaged or ungauged watersheds. Many modelers have used the documented SCS-CN parameters without calibration, sometimes resulting in significant errors in estimating surface runoff. Several methods for regionalization of SCS-CN parameters were evaluated. The regionalization methods include: (1 average; (2 land use area weighted average; (3 hydrologic soil group area weighted average; (4 area combined land use and hydrologic soil group weighted average; (5 spatial nearest neighbor; (6 inverse distance weighted average; and (7 global calibration method, and model performance for each method was evaluated with application to 14 watersheds located in Indiana. Eight watersheds were used for calibration and six watersheds for validation. For the validation results, the spatial nearest neighbor method provided the highest average Nash-Sutcliffe (NS value at 0.58 for six watersheds but it included the lowest NS value and variance of NS values of this method was the highest. The global calibration method provided the second highest average NS value at 0.56 with low variation of NS values. Although the spatial nearest neighbor method provided the highest average NS value, this method was not statistically different than other methods. However, the global calibration method was significantly different than other methods except the spatial nearest neighbor method. Therefore, we conclude that the global calibration method is appropriate to regionalize SCS-CN parameters for ungauged watersheds.

  12. Histone fractionation by high-performance liquid chromatography on cyanoalkylsilane (CN) reverse-phase columns

    International Nuclear Information System (INIS)

    Gurley, L.R.; Prentice, D.A.; Valdez, J.G.; Spall, W.D.

    1983-01-01

    Previous work described conditions for the rapid fractionation of histones by high-performance liquid chromatography (HPLC) using a reverse-phase μBondapak C 18 column. That procedure resolved the major classes of histones with one exception: the more hydrophobic H2A variant, (MHP)H2A, was not resolved from the H4 histone class. This report extends that work describing experiments using a μBondapak CN column which better resolves the classes of histones from each other including the resolution of (MHP)H2A from the H4. In addition, the less hydrophobic H2A variant, (LHP)H2A, is partially resolved from the (MHP)H2A, and the less hydrophobic H3 variant, (LHP)H3, is resolved from the more hydrophobic H3 variant, (MHP)H3. Lower trifluoroacetic acid (TFA) concentrations (0.1%) in the eluting water/acetonitrile solvent were used with the CN column than were used with the C 18 column which increased the sensitivity of histone detection by ultraviolet absorption at 206 nm. Greater than 95% of the total [ 3 H]lysine-labeled protein applied to the CN column was eluted from the column. Contaminating nonhistone proteins were found to chromatograph in the region of histone elution. These were greatly reduced by isolating nuclei prior to histone preparation. The fractionation of the histones appears to be based on the hydrophobic properties of the proteins. The histone fractions (identified by their electrophoretic mobilities) were eluted from the CN column in the following order: H1, H2B, (LHP)H2A, (MHP)H2A, H4, (LHP)H3, and (MHP)H3. Phosphorylated and acetylated histone species were not resolved from their unmodified parental species

  13. Identification of the c(10×6)-CN/Cu(001) surface structure

    KAUST Repository

    Shuttleworth, I.G.

    2014-01-01

    © 2014 Elsevier B.V. All rights reserved. A systematic survey of all possible c(10 x 6)-CN/Cu(0 0 1) structures has been performed using density functional theory (DFT). A group of four preferred structures is presented with one of the structures identified as optimal. An analysis of the bonding within the optimal structure has shown that a significant localisation of the surface Cu 4s bonds occurs in the saturated system.

  14. Identification of the c(10×6)-CN/Cu(001) surface structure

    KAUST Repository

    Shuttleworth, I.G.

    2014-12-01

    © 2014 Elsevier B.V. All rights reserved. A systematic survey of all possible c(10 x 6)-CN/Cu(0 0 1) structures has been performed using density functional theory (DFT). A group of four preferred structures is presented with one of the structures identified as optimal. An analysis of the bonding within the optimal structure has shown that a significant localisation of the surface Cu 4s bonds occurs in the saturated system.

  15. Syntheses, structures, and magnetic properties of three new MnII-[MoIII(CN)7]4- molecular magnets.

    Science.gov (United States)

    Wei, Xiao-Qin; Pi, Qian; Shen, Fu-Xing; Shao, Dong; Wei, Hai-Yan; Wang, Xin-Yi

    2018-05-22

    By reaction of K4[MoIII(CN)7]·2H2O, Mn(ClO4)2·6H2O and bidentate chelating ligands, three new cyano-bridged compounds, namely Mn2(3-pypz)(H2O)(CH3CN)[Mo(CN)7] (1), Mn2(1-pypz)(H2O)(CH3CN)[Mo(CN)7] (2) and Mn2(pyim)(H2O)(CH3CN)[Mo(CN)7] (3) (3-pypz = 2-(1H-pyrazol-3-yl)pyridine, 1-pypz = 2-(1H-pyrazol-1-yl)pyridine, pyim = 2-(1H-imidazol-2-yl)pyridine), have been synthesized and characterized structurally and magnetically. Single crystal X-ray analyses revealed that although the chelating ligands are different, compounds 1 to 3 are isomorphous and crystallize in the same monoclinic space group C2/m. Connected by the bridging cyano groups, one crystallographically unique [Mo(CN)7]4- unit and three crystallographically unique MnII ions of different coordination environments form similar three-dimensional frameworks, which have a four-nodal 3,4,4,7-connecting topological net with a vertex symbol of {43}{44·62}2{410·611}. Magnetic measurements revealed that compounds 1-3 display long-range magnetic ordering with critical temperatures of 64, 66 and 62 K, respectively. These compounds are rare examples of a small number of chelating co-ligand coordinated [Mo(CN)7]4--based magnetic materials. Specifically, the bidentate chelating ligands were successfully introduced into the heptacyanomolybdate system for the first time.

  16. Wide band ENDOR spectrometer

    International Nuclear Information System (INIS)

    Mendonca Filho, C.

    1973-01-01

    The construction of an ENDOR spectrometer operating from 0,5 to 75 MHz within a single band, with ore Klystron and homodine detection, and no fundamental changes on the electron spin resonance spectrometer was described. The ENDOR signal can be detected both by amplitude modulation of the frequency field, or direct detection of the ESR output, which is taken to a signal analyser. The signal-to-noise ratio is raised by averaging rather than filtering avoiding the use of long time constants, providing natural line widths. The experimental apparatus and the spectra obtained are described. A discussion, relating the ENDOR line amplitudes with the experimental conditions is done and ENDOR mechanism, in which there is a relevant presence of cross relaxation is proposed

  17. Electronic band structure

    International Nuclear Information System (INIS)

    Grosso, G.

    1986-01-01

    The aim of this chapter is to present, in detail, some theoretical methods used to calculate electronic band structures in crystals. The basic strategies employed to attack the problem of electronic-structure calculations are presented. Successive sections present the basic formulations of the tight-binding, orthogonalized-plane-wave, Green'sfunction, and pseudopotential methods with a discussion of their application to perfect solids. Exemplifications in the case of a few selected problems provide further insight by the author into the physical aspects of the different methods and are a guide to the use of their mathematical techniques. A discussion is offered of completely a priori Hartree-Fock calculations and attempts to extend them. Special aspects of the different methods are also discussed in light of recently published related work

  18. Crystallization and preliminary crystallographic study of carnosinase CN2 from mice

    Energy Technology Data Exchange (ETDEWEB)

    Yamashita, Tetsuo; Unno, Hideaki; Ujita, Sayuri; Otani, Hiroto; Okumura, Nobuaki; Hashida-Okumura, Akiko; Nagai, Katsuya; Kusunoki, Masami, E-mail: kusunoki@protein.osaka-u.ac.jp [Institute for Protein Research, Osaka University, 3-2 Yamada-oka, Suita, Osaka 565-0871 (Japan)

    2006-10-01

    Mouse carnosinase was crystallized in complex with Zn{sup 2+} or Mn{sup 2+} and the complexes are undergoing structure determination by the MAD method. Mammalian tissues contain several histidine-containing dipeptides, of which l-carnosine is the best characterized and is found in various tissues including the brain and skeletal muscles. However, the mechanism for its biosynthesis and degradation have not yet been fully elucidated. Crystallographic study of carnosinase CN2 from mouse has been undertaken in order to understand its enzymatic mechanism from a structural viewpoint. CN2 was crystallized by the hanging-drop vapour-diffusion technique using PEG 3350 as a precipitant. Crystals were obtained in complex with either Mn{sup 2+} or Zn{sup 2+}. Both crystals of CN2 belong to the monoclinic space group P2{sub 1} and have almost identical unit-cell parameters (a = 54.41, b = 199.77, c = 55.49 Å, β = 118.52° for the Zn{sup 2+} complex crystals). Diffraction data were collected to 1.7 and 2.3 Å for Zn{sup 2+} and Mn{sup 2+} complex crystals, respectively, using synchrotron radiation. Structure determination is ongoing using the multiple-wavelength anomalous diffraction (MAD) method.

  19. Crystallization and preliminary crystallographic study of carnosinase CN2 from mice

    International Nuclear Information System (INIS)

    Yamashita, Tetsuo; Unno, Hideaki; Ujita, Sayuri; Otani, Hiroto; Okumura, Nobuaki; Hashida-Okumura, Akiko; Nagai, Katsuya; Kusunoki, Masami

    2006-01-01

    Mouse carnosinase was crystallized in complex with Zn 2+ or Mn 2+ and the complexes are undergoing structure determination by the MAD method. Mammalian tissues contain several histidine-containing dipeptides, of which l-carnosine is the best characterized and is found in various tissues including the brain and skeletal muscles. However, the mechanism for its biosynthesis and degradation have not yet been fully elucidated. Crystallographic study of carnosinase CN2 from mouse has been undertaken in order to understand its enzymatic mechanism from a structural viewpoint. CN2 was crystallized by the hanging-drop vapour-diffusion technique using PEG 3350 as a precipitant. Crystals were obtained in complex with either Mn 2+ or Zn 2+ . Both crystals of CN2 belong to the monoclinic space group P2 1 and have almost identical unit-cell parameters (a = 54.41, b = 199.77, c = 55.49 Å, β = 118.52° for the Zn 2+ complex crystals). Diffraction data were collected to 1.7 and 2.3 Å for Zn 2+ and Mn 2+ complex crystals, respectively, using synchrotron radiation. Structure determination is ongoing using the multiple-wavelength anomalous diffraction (MAD) method

  20. TEGS-CN: A Statistical Method for Pathway Analysis of Genome-wide Copy Number Profile.

    Science.gov (United States)

    Huang, Yen-Tsung; Hsu, Thomas; Christiani, David C

    2014-01-01

    The effects of copy number alterations make up a significant part of the tumor genome profile, but pathway analyses of these alterations are still not well established. We proposed a novel method to analyze multiple copy numbers of genes within a pathway, termed Test for the Effect of a Gene Set with Copy Number data (TEGS-CN). TEGS-CN was adapted from TEGS, a method that we previously developed for gene expression data using a variance component score test. With additional development, we extend the method to analyze DNA copy number data, accounting for different sizes and thus various numbers of copy number probes in genes. The test statistic follows a mixture of X (2) distributions that can be obtained using permutation with scaled X (2) approximation. We conducted simulation studies to evaluate the size and the power of TEGS-CN and to compare its performance with TEGS. We analyzed a genome-wide copy number data from 264 patients of non-small-cell lung cancer. With the Molecular Signatures Database (MSigDB) pathway database, the genome-wide copy number data can be classified into 1814 biological pathways or gene sets. We investigated associations of the copy number profile of the 1814 gene sets with pack-years of cigarette smoking. Our analysis revealed five pathways with significant P values after Bonferroni adjustment (number data, and causal mechanisms of the five pathways require further study.

  1. Thermochemistry of the reactions between CN+ and H2O in the gas phase

    Science.gov (United States)

    Ijjaali, Fatima; Alcami, Manuel; Mo, Otilia; Yanez, Manuel

    The [H2, C, N, O]+ potential energy surface (PES) has been explored by means of high-level ab initio calculations, carried out in the framework of the G2 theory. From this survey we concluded that the predominant products of the CN+ +H2O reaction are the result of the dissociation of HNCOH+ species and to a much lesser extent of the CNHOH+ cation to yield CNH+ +OH. According to our results HCN+ should not be a product of this reaction because all pathways leading to its formation are unfavourable with regards to other competitive processes. Other reactive channels lead to the formation of the H2ONC+ structure which dissociates into CN + H2O+. The loss of NH(3Σ) and O(3P) seems to take place following spin-forbidden reaction paths through an intersystem crossing between the singlet and the triplet PESs. The global minimum of the PES, H2NCO+ is easily accessible and should lead to the loss of carbon monoxide which has not been experimentally observed in CN+ + H2O reactions. We cannot oOEer a clear explanation for this disagreement between theory and experiment.

  2. The Cn method applied to problems with an anisotropic diffusion law

    International Nuclear Information System (INIS)

    Grandjean, P.M.

    A 2-dimensional Cn calculation has been applied to homogeneous media subjected to the Rayleigh impact law. Results obtained with collision probabilities and Chandrasekhar calculations are compared to those from Cn method. Introducing in the expression of the transport equation, an expansion truncated on a polynomial basis for the outgoing angular flux (or possibly entrance flux) gives two Cn systems of algebraic linear equations for the expansion coefficients. The matrix elements of these equations are the moments of the Green function in infinite medium. The search for the Green function is effected through the Fourier transformation of the integrodifferential equation and its moments are derived from their Fourier transforms through a numerical integration in the complex plane. The method has been used for calculating the albedo in semi-infinite media, the extrapolation length of the Milne problem, and the albedo and transmission factor of a slab (a concise study of convergence is presented). A system of integro-differential equations bearing on the moments of the angular flux inside the medium has been derived, for the collision probability method. It is numerically solved with approximately the bulk flux by step functions. The albedo in semi-infinite medium has also been computed through the semi-analytical Chandrasekhar method. In the latter, the outgoing flux is expressed as a function of the entrance flux by means of a integral whose kernel is numerically derived [fr

  3. Friction and wear of TiCN coatings deposited by filtered arc

    International Nuclear Information System (INIS)

    Huang, S.W.; Ng, K.; Samandi, M.

    1998-01-01

    A series of macroparticle-free TiN, TiCN and TiC coatings were deposited on 316 austenitic stainless steel using a titanium target in a filtered arc deposition system and reactive mixtures of CH4 and N2 gases. The microhardness of the coatings were measured by using an Ultra Microhardness Indentation System (UMIS-2000). The wear and friction of the coatings were assessed under controlled test conditions in a pin-on-disc tribometer. The results show a significant increase in microhardness and wear resistance as the CH4 :N2 gas flow rate ratio is increased. At lower load (14N), all coatings exhibited low friction and wear. At higher load (25N), the higher carbon content TiCN and TiC coatings showed a much lower friction and wear compared to TiN and low carbon TiCN. The topographical examination of coatings and worn surfaces established that the self-lubricating effect of the carbonaceous particles condensed from the plasma during the deposition was primarily responsible for the low friction and wear regime. (authors)

  4. Extraction of benzene and cyclohexane using [BMIM][N(CN)2] and their equilibrium modeling

    Science.gov (United States)

    Ismail, Marhaina; Bustam, M. Azmi; Man, Zakaria

    2017-12-01

    The separation of aromatic compound from aliphatic mixture is one of the essential industrial processes for an economically green process. In order to determine the separation efficiency of ionic liquid (IL) as a solvent in the separation, the ternary diagram of liquid-liquid extraction (LLE) 1-butyl-3-methylimidazolium dicyanamide [BMIM][N(CN)2] with benzene and cyclohexane was studied at T=298.15 K and atmospheric pressure. The solute distribution coefficient and solvent selectivity derived from the equilibrium data were used to evaluate if the selected ionic liquid can be considered as potential solvent for the separation of benzene from cyclohexane. The experimental tie line data was correlated using non-random two liquid model (NRTL) and Margules model. It was found that the solute distribution coefficient is (0.4430-0.0776) and selectivity of [BMIM][N(CN)2] for benzene is (53.6-13.9). The ternary diagram showed that the selected IL can perform the separation of benzene and cyclohexane as it has extractive capacity and selectivity. Therefore, [BMIM][N(CN)2] can be considered as a potential extracting solvent for the LLE of benzene and cyclohexane.

  5. Study on optoelectronic properties of Spiro-CN for developing an efficient OLED

    Science.gov (United States)

    Mishra, Ashok Kumar

    2018-05-01

    There are a class of organic molecules and polymers which exhibit semiconductor behavior because of nearly free conjugate π-electrons. Hopping of these electrons in molecules forms different excited singlet and triplet states named as excitons. Some of these organic molecules can be set to emit photons by triplet-singlet excitonic transition via a process called Thermally Activated Delayed Fluorescence (TADF) which is exploited for designing the Organic Light Emitting diode (OLED.) Spiro-CN (spirobifluorene skeletons) Spiro is one of these reported noble metal-free TADF molecules which offers unique optical and electronic properties arising from the efficient transition and reverse intersystem crossing between the lowest singlet (S) and triplet (T) excited states. Its ability to harvest triplet excitons for fluorescence through facilitated reverse intersystem crossing (T→S) could directly impact their properties and performances, which is attractive for a wide variety of low-cost optoelectronic device. In the present study, the Spiro-CN compounds have been taken up for the investigation of various optoelectronic properties including the thermally activated delayed fluorescence (TADF) by using the Koopmans Method and Density Functional Theory. The present study discusses the utility of the Spiro-CN organic semiconductor as a suitable TADF material essential for developing an efficient Organic Light Emitting Diode (OLED).

  6. Fine-structure resolved rotational transitions and database for CN+H2 collisions

    Science.gov (United States)

    Burton, Hannah; Mysliwiec, Ryan; Forrey, Robert C.; Yang, B. H.; Stancil, P. C.; Balakrishnan, N.

    2018-06-01

    Cross sections and rate coefficients for CN+H2 collisions are calculated using the coupled states (CS) approximation. The calculations are benchmarked against more accurate close-coupling (CC) calculations for transitions between low-lying rotational states. Comparisons are made between the two formulations for collision energies greater than 10 cm-1. The CS approximation is used to construct a database which includes highly excited rotational states that are beyond the practical limitations of the CC method. The database includes fine-structure resolved rotational quenching transitions for v = 0 and j ≤ 40, where v and j are the vibrational and rotational quantum numbers of the initial state of the CN molecule. Rate coefficients are computed for both para-H2 and ortho-H2 colliders. The results are shown to be in good agreement with previous calculations, however, the rates are substantially different from mass-scaled CN+He rates that are often used in astrophysical models.

  7. TiCN thin films grown by reactive crossed beam pulsed laser deposition

    Science.gov (United States)

    Escobar-Alarcón, L.; Camps, E.; Romero, S.; Muhl, S.; Camps, I.; Haro-Poniatowski, E.

    2010-12-01

    In this work, we used a crossed plasma configuration where the ablation of two different targets in a reactive atmosphere was performed to prepare nanocrystalline thin films of ternary compounds. In order to assess this alternative deposition configuration, titanium carbonitride (TiCN) thin films were deposited. Two crossed plasmas were produced by simultaneously ablating titanium and graphite targets in an Ar/N2 atmosphere. Films were deposited at room temperature onto Si (100) and AISI 4140 steel substrates whilst keeping the ablation conditions of the Ti target constant. By varying the laser fluence on the carbon target it was possible to study the effect of the carbon plasma on the characteristics of the deposited TiCN films. The structure and composition of the films were analyzed by X-ray Diffraction, Raman Spectroscopy and non-Rutherford Backscattering Spectroscopy. The hardness and elastic modulus of the films was also measured by nanoindentation. In general, the experimental results showed that the TiCN thin films were highly oriented in the (111) crystallographic direction with crystallite sizes as small as 6.0 nm. It was found that the hardness increased as the laser fluence was increased, reaching a maximum value of about 33 GPa and an elastic modulus of 244 GPa. With the proposed configuration, the carbon content could be easily varied from 42 to 5 at.% by changing the laser fluence on the carbon target.

  8. Supramolecular architecture based on [Fe(CN)6]3- metallotectons and melaminium synthons

    Science.gov (United States)

    Krichen, Firas; Walha, Siwar; Lhoste, Jérôme; Bulou, Alain; Kabadou, Ahlem; Goutenoire, François

    2017-10-01

    Assembly involving [Fe(CN)6]3- metallotectons as building units and melaminium organic cation has been envisioned in order to elaborate a hybrid supramolecular based on ionic H-bonds with formula {(H-mel)4[Fe(CN)6]Cl} (H-mel+: melaminium cation). The compound has been prepared by diffusion method and characterized by single-crystal X-ray diffraction, EDX analysis, and Raman-IR spectroscopies with assignment from ab initio calculations. The melaminium exhibit self cationic coupling with cyclic hydrogen bonds to give a one dimensional {[H-mel]+}∝ synthon. Therefore, these cationic ribbons are inter-linked via hydrogen bonds by the anionic tectons [Fe(CN)6]3- and chlorine anion resulting on a 3D network. Molecular hirshfeld surfaces revealed that the crystal structure has been supported mainly by Nsbnd H⋯N and Nsbnd H⋯Cl intermolecular Hydrogen bonds and by favoured C⋯C and C⋯N weak interactions.

  9. Low energy electron attachment to cyanamide (NH{sub 2}CN)

    Energy Technology Data Exchange (ETDEWEB)

    Tanzer, Katrin; Denifl, Stephan, E-mail: Andrzej.Pelc@poczta.umcs.lublin.pl, E-mail: Stephan.Denifl@uibk.ac.at [Institut für Ionenphysik und Angewandte Physik, Leopold Franzens Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); Pelc, Andrzej, E-mail: Andrzej.Pelc@poczta.umcs.lublin.pl, E-mail: Stephan.Denifl@uibk.ac.at [Mass Spectrometry Department, Institute of Physics, Marie Curie-Sklodowska University, Pl. M. C.-Sklodowskiej 1, 20-031 Lublin (Poland); Huber, Stefan E. [Institut für Ionenphysik und Angewandte Physik, Leopold Franzens Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck (Austria); Lehrstuhl für Theoretische Chemie, Technische Universität München, Lichtenbergstr. 4, 85747 Garching (Germany); Czupyt, Z. [Ion Microprobe Facility Micro-area Analysis Laboratory, Polish Geological Institute–National Research Institute, Rakowiecka 4, 00-975 Warszawa (Poland)

    2015-01-21

    Cyanamide (NH{sub 2}CN) is a molecule relevant for interstellar chemistry and the chemical evolution of life. In the present investigation, dissociative electron attachment to NH{sub 2}CN has been studied in a crossed electron–molecular beams experiment in the electron energy range from about 0 eV to 14 eV. The following anionic species were detected: NHCN{sup −}, NCN{sup −}, CN{sup −}, NH{sub 2}{sup −}, NH{sup −}, and CH{sub 2}{sup −}. The anion formation proceeds within two broad electron energy regions, one between about 0.5 and 4.5 eV and a second between 4.5 and 12 eV. A discussion of possible reaction channels for all measured negative ions is provided. The experimental results are compared with calculations of the thermochemical thresholds of the anions observed. For the dehydrogenated parent anion, we explain the deviation between the experimental appearance energy of the anion with the calculated corresponding reaction threshold by electron attachment to the isomeric form of NH{sub 2}CN—carbodiimide.

  10. Influence of trimethylsilane flow on the microstructure, mechanical and tribological properties of CrSiCN coatings in water lubrication

    International Nuclear Information System (INIS)

    Wu, Zhiwei; Zhou, Fei; Wang, Qianzhi; Zhou, Zhifeng; Yan, Jiwang; Li, Lawrence Kwok-Yan

    2015-01-01

    Highlights: • CrSiCN coatings with different Si and C contents were deposited. • CrSiCN coatings consisted of Cr(C,N) nanocrystallites and amorphous phases such as a-Si_3N_4(SiC, SiCN) and a-C(a-CN_x). • CrSiCN coatings exhibited the highest hardness of 21.3 GPa at the TMS flow of 10 sccm. • CrSiCN coatings deposited at the TMS flow of 10 sccm possessed the excellent tribological properties in water. • The wear mechanism changed from tribochemical wear to mechanical wear when the TMS flow increased. - Abstract: CrSiCN coatings with different silicon and carbon contents were deposited on silicon wafers and 316L stainless steels using unbalanced magnetron sputtering via adjusting trimethylsilane (TMS) flow, and their microstructure and mechanical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy(SEM), X-ray photoelectrons spectroscopy(XPS) and nano-indenter, respectively. The tribological properties of CrSiCN coatings sliding against SiC balls in water were investigated using ball-on-disk tribometer. The results showed that the CrSiCN coatings had fine composite microstructure consisting of nanocrystallites of Cr(C, N) crystal and amorphous phases such as a-Si_3N_4 and a-C(a-CN_x). The typical columnar structures changed from fine cluster to coarse ones when the Si content was beyond 3.4 at.%. With an increase in the TMS flow, the hardness and Young's modulus of Corsican coatings all first increased, and then rapidly decreased, but the compressive stress in the coatings varied in the range of 2.8–4.8 GPa. When the TMS flow was 10 sccm, the CrSiCN coatings exhibited the highest hardness of 21.3 GPa and the lowest friction coefficient (0.11) and wear rate (8.4 × 10"−"8 mm"3/N m). But when the TMS flow was beyond 15 sccm, the tribological properties of CrSiCN coatings in water became poor.

  11. Comparison of different models for ground-level atmospheric turbulence strength (C(n)(2)) prediction with a new model according to local weather data for FSO applications.

    Science.gov (United States)

    Arockia Bazil Raj, A; Arputha Vijaya Selvi, J; Durairaj, S

    2015-02-01

    Atmospheric parameters strongly affect the performance of free-space optical communication (FSOC) systems when the optical wave is propagating through the inhomogeneous turbulence transmission medium. Developing a model to get an accurate prediction of the atmospheric turbulence strength (C(n)(2)) according to meteorological parameters (weather data) becomes significant to understand the behavior of the FSOC channel during different seasons. The construction of a dedicated free-space optical link for the range of 0.5 km at an altitude of 15.25 m built at Thanjavur (Tamil Nadu) is described in this paper. The power level and beam centroid information of the received signal are measured continuously with weather data at the same time using an optoelectronic assembly and the developed weather station, respectively, and are recorded in a data-logging computer. Existing models that exhibit relatively fewer prediction errors are briefed and are selected for comparative analysis. Measured weather data (as input factors) and C(n)(2) (as a response factor) of size [177,147×4] are used for linear regression analysis and to design mathematical models more suitable in the test field. Along with the model formulation methodologies, we have presented the contributions of the input factors' individual and combined effects on the response surface and the coefficient of determination (R(2)) estimated using analysis of variance tools. An R(2) value of 98.93% is obtained using the new model, model equation V, from a confirmatory test conducted with a testing data set of size [2000×4]. In addition, the prediction accuracies of the selected and the new models are investigated during different seasons in a one-year period using the statistics of day, week-averaged, month-averaged, and seasonal-averaged diurnal Cn2 profiles, and are verified in terms of the sum of absolute error (SAE). A Cn2 prediction maximum average SAE of 2.3×10(-13)  m(-2/3) is achieved using the new model in

  12. Effect of strong coupling on interfacial electron transfer dynamics in ...

    Indian Academy of Sciences (India)

    Unknown

    regarded as the best sensitizing dyes for solar energy conversion for their strong visible absorption bands, long-lived ... solar cells based on dye-sensitized nanocrystalline. TiO2. High affinity for the TiO2 surface, which is ... pump pulses at 400 nm, one part of 800 nm with. 200 µJ/pulse, is frequency doubled in BBO crystals.

  13. Cellular uptake of exogenous calcineurin B is dependent on TLR4/MD2/CD14 complexes, and CnB is an endogenous ligand of TLR4.

    Science.gov (United States)

    Yang, Jinju; Qin, Nannan; Zhang, Hongwei; Yang, Rui; Xiang, Benqiong; Wei, Qun

    2016-04-19

    Our previous research showed that recombinant calcineurin B (rhCnB) stimulates cytokine secretion by immune cells, probably through TLR4. Exogenous CnB can be incorporated into many different tumour cells in vitro, but the mode of uptake and receptors required remain unknown. Here, we report that exogenous CnB is taken up by cells in a time- and concentration-dependent manner via clathrin-dependent receptor-mediated internalization. Our findings further confirm that uptake is mediated by the TLR4/MD2 complex together with the co-receptor CD14. The MST results revealed a high affinity between CnB and the TLR4 receptor complex. No binding was detected between CnB and LPS. CnB inhibited the uptake of LPS, and LPS also inhibited the uptake of CnB. These results indicate that the uptake of exogenous CnB did not occur through LPS and that CnB was not a chaperone of LPS. Thus, we conclude that TLR4 receptor complexes were required for the recognition and internalization of exogenous CnB. CnB could be a potential endogenous ligand of TLR4 and function as an agonist of TLR4. These properties of CnB support its potential for development as an anti-cancer drug.

  14. Electronic transport properties of Ti-impurity band in Si

    Energy Technology Data Exchange (ETDEWEB)

    Olea, J; Gonzalez-Diaz, G; Pastor, D; Martil, I [Departamento de Fisica Aplicada III (Electricidad y Electronica), Facultad de Ciencias, Fisicas, Universidad Complutense, E-28040 Madrid (Spain)

    2009-04-21

    In this paper we show that pulsed laser melted high dose implantation of Ti in Si, above the Mott transition, produces an impurity band (IB) in this semiconductor. Using the van der Pauw method and Hall effect measurements we find strong laminated conductivity at the implanted layer and a temperature dependent decoupling between the Ti implanted layer (TIL) and the substrate. The conduction mechanism from the TIL to the substrate shows blocking characteristics that could be well explained through IB theory. Using the ATLAS code we can estimate the energetic position of the IB at 0.36 eV from the conduction band, the density of holes in this band which is closely related to the Ti atomic density and the hole mobility in this band. Band diagrams of the structure at low and high temperatures are also simulated in the ATLAS framework. The simulation obtained is fully coherent with experimental results.

  15. Electronic transport properties of Ti-impurity band in Si

    International Nuclear Information System (INIS)

    Olea, J; Gonzalez-Diaz, G; Pastor, D; Martil, I

    2009-01-01

    In this paper we show that pulsed laser melted high dose implantation of Ti in Si, above the Mott transition, produces an impurity band (IB) in this semiconductor. Using the van der Pauw method and Hall effect measurements we find strong laminated conductivity at the implanted layer and a temperature dependent decoupling between the Ti implanted layer (TIL) and the substrate. The conduction mechanism from the TIL to the substrate shows blocking characteristics that could be well explained through IB theory. Using the ATLAS code we can estimate the energetic position of the IB at 0.36 eV from the conduction band, the density of holes in this band which is closely related to the Ti atomic density and the hole mobility in this band. Band diagrams of the structure at low and high temperatures are also simulated in the ATLAS framework. The simulation obtained is fully coherent with experimental results.

  16. Investigation of the Effect of He-Ne Laser on the Optical Properties through Etched CN-85 and CR-39 Containing Alpha Tracks

    International Nuclear Information System (INIS)

    Zaki, M.F.; Hegazy, T.M.; Taha, D.H.

    2013-01-01

    The effects of He-Ne laser on the optical characteristics of Cellulose nitrate, CN-85, and Poly allyl diglycole carbonate, CR-39, nuclear track detectors have been studied by using photoluminescence (PL) and UV-visible spectroscopic techniques. The polymers irradiated with alpha particles with close contact to 241 Am and then exposed to He-Ne laser with different doses. The laser energy intensities ranged between 0 and 217 J/cm 2 . The change in the PL spectra may be explained by chain conformational disorders as well as chain scission. From the UV-visible spectra, it is found that a shift in the absorption edge towards a longer wavelength with increasing laser doses can be readily observed. The absorption peak with increasing dose is seen to change into a broad one. The optical band gaps determined from the UV-visible spectra were found to decrease with the increase of energy intensities of He-Ne laser. These results have been explained on the basis of scission of the polymers due to laser irradiation. The UV absorption tail formation in both polymers was related to the diminution of optical band gap. Results show good correlation with the applied doses.

  17. What band rocks the MTB? (Invited)

    Science.gov (United States)

    Kind, J.; García-Rubio, I.; Gehring, A. U.

    2013-12-01

    Magnetotactic bacteria (MTB) are a polyphyletic group of bacteria that have been found in marine and lacustrine environments and soils [e.g. 1]. The hallmark of MTB is their intracellular formation of magnetosomes, single-domain ferrimagnetic particles that are aligned in chains. The chain configuration generates a strong magnetic dipole, which is used as magnetic compass to move the MTB into their favorable habit. The term band corresponds to a frequency window of microwaves in the gigahertz (GHz) range. Ferromagnetic resonance (FMR) spectroscopy uses the microwave absorption in a magnetic field to analyze the anisotropy properties and the domain state of magnetic materials. Specific microwave frequency causes absorption in a characteristic magnetic field range. For the investigation of MTB we use S-band (4.02 GHz), X-band (9.47 GHz), and Q-band (34.16 GHz). Experiments on cultured MTB and on sediment samples of Holocene age showed that absorption in X- and Q-band occurs when the sample is in a saturated or nearly saturated state [2, 3]. By contrast, absorption in the S-band appears in lower magnetic fields, where the sample is far from saturation. All FMR spectra show two distinct low-field features that can be assigned to magnetite particles in chains, aligned parallel and perpendicular to the external magnetic field. The detailed separation of the parallel and perpendicular components in the bulk samples is hampered, because of the random orientation of the chains in the sample. The comparison of S-, X-, and Q-band shows that the lower the frequency the better the separation of the components. In the S-band FMR spectroscopy, the separation of chains parallel to the external magnetic field is supported by the internal field of the sample. This field is caused by the remanence that contributes to the external magnetic field to fulfill the resonance condition [3,4]. Considering the different FMR responses, it can be postulated that a lower microwave frequency

  18. [Fe(III)(dmbpy)(CN)4]-: a new building block for designing single-chain magnets.

    Science.gov (United States)

    Toma, Luminita Marilena; Pasán, Jorge; Ruiz-Pérez, Catalina; Lloret, Francesc; Julve, Miguel

    2012-11-28

    We herein present the synthesis and magneto-structural study of a new family of heterobimetallic chains of general formula {[Fe(III)(dmbpy)(CN)(4)](2)M(II)(H(2)O)(2)}(n)·pnH(2)O [dmbpy = 4,4'-dimethyl-2,2'-bipyridine; M = Mn (2), Cu (3), Ni (4) and Co (5) with p = 4 (2), 3 (3), 9 (4) and 3.5 (5)] which were prepared by using the mononuclear PPh(4)[Fe(III)(dmbpy)(CN)(4)]·3H(2)O (1) building block (PPh(4)(+) = tetraphenylphosphonium) as a ligand toward fully solvated M(II) ions. The structure of 1 consists of discrete [Fe(III)(dmbpy)(CN)(4)](-) anions, tetraphenylphosphonium cations and noncoordinated water molecules. Complexes 2-5 are isostructural compounds whose structure consists of neutral 4,2-wave like heterobimetallic chains of formula {[Fe(III)(dmbpy)(CN)(4)](2)M(II)(H(2)O)(2)}(n) where the [Fe(III)(dmbpy)(CN)(4)](-) entity adopts a bis-monodentate coordination mode toward trans-[M(II)(H(2)O)(2)] units through two of its four cyanide groups in cis positions. 1 exhibits the magnetic behaviour of magnetically isolated six-coordinate low-spin Fe(III) complexes with an important orbital contribution. 2 behaves as ferrimagnetic Fe(III)(2)Mn(II) chains, whereas 3-5 exhibit intrachain ferromagnetic couplings between the low-spin Fe(III) and either Cu(II) (3), Ni (4) or Co(II) (5) as well as frequency-dependence of the out-of-phase ac susceptibility signals below 3.0 (3), 5.5 (4) and 5.0 K (5). The relaxation time and the energy to reverse the magnetization of 3-5 are related to the anisotropy of the M(II) center and to the intra- and interchain magnetic interactions. Unprecedentedly in the world of cyanide-bearing complexes, 5 exhibits a double slow relaxation of the magnetization.

  19. Genetic variation in pea (Pisum sativum L.) demonstrates the importance of root but not shoot C/N ratios in the control of plant morphology and reveals a unique relationship between shoot length and nodulation intensity.

    Science.gov (United States)

    Ludidi, Ndiko N; Pellny, Till K; Kiddle, Guy; Dutilleul, Christelle; Groten, Karin; VAN Heerden, Philippus D R; Dutt, Som; Powers, Stephen J; Römer, Peter; Foyer, Christine H

    2007-10-01

    Nodule numbers are regulated through systemic auto-regulatory signals produced by shoots and roots. The relative effects of shoot and root genotype on nodule numbers together with relationships to organ biomass, carbon (C) and nitrogen (N) status, and related parameters were measured in pea (Pisum sativum) exploiting natural genetic variation in maturity and apparent nodulation intensity. Reciprocal grafting experiments between the early (Athos), intermediate (Phönix) and late (S00182) maturity phenotypes were performed and Pearson's correlation coefficients for the parameters were calculated. No significant correlations were found between shoot C/N ratios and plant morphology parameters, but the root C/N ratio showed a strong correlation with root fresh and dry weights as well as with shoot fresh weight with less significant interactions with leaf number. Hence, the root C/N ratio rather than shoot C/N had a predominant influence on plant morphology when pea plants are grown under conditions of symbiotic nitrogen supply. The only phenotypic characteristic that showed a statistically significant correlation with nodulation intensity was shoot length, which accounted for 68.5% of the variation. A strong linear relationship was demonstrated between shoot length and nodule numbers. Hence, pea nodule numbers are controlled by factors related to shoot extension, but not by shoot or root biomass accumulation, total C or total N. The relationship between shoot length and nodule numbers persisted under field conditions. These results suggest that stem height could be used as a breeding marker for the selection of pea cultivars with high nodule numbers and high seed N contents.

  20. Polymer-derived Ceramic SiCN-MoS2 Nanosheet Composite for Lithium Ion Battery Anodes

    Science.gov (United States)

    Bhandavat, Romil; Singh, Gurpreet

    2012-02-01

    We demonstrate synthesis of a novel SiCN-MoS2 nanosheet composite for use as Li-ion battery anode for high power applications. The nanosheet composite was prepared by thermal decomposition of polysilazane (SiCN precursor) on exfoliated MoS2 surfaces. The morphology and chemical structure was studied using a range of spectroscopy techniques that revealed a sidewall functionalization of exfoliated MoS2 by the polymeric precursor. The thermodynamic stability of SiCN-MoS2 nanosheets was also confirmed by thermo-gravimetric analysis (1000 degree C). Batteries assembled using MoS2-SiCN nanosheets as active anode material showed that lithium can be reversibly intercalated in the voltage range of 0-2.5 V with first cycle discharge capacity of 620 mAh/g at a current density of 100 mA/g.

  1. Estimating Composite Curve Number Using an Improved SCS-CN Method with Remotely Sensed Variables in Guangzhou, China

    OpenAIRE

    Fan, Fenglei; Deng, Yingbin; Hu, Xuefei; Weng, Qihao

    2013-01-01

    The rainfall and runoff relationship becomes an intriguing issue as urbanization continues to evolve worldwide. In this paper, we developed a simulation model based on the soil conservation service curve number (SCS-CN) method to analyze the rainfall-runoff relationship in Guangzhou, a rapid growing metropolitan area in southern China. The SCS-CN method was initially developed by the Natural Resources Conservation Service (NRCS) of the United States Department of Agriculture (USDA), and is on...

  2. Terra MODIS Band 27 Electronic Crosstalk Effect and Its Removal

    Science.gov (United States)

    Sun, Junqiang; Xiong, Xiaoxiong; Madhavan, Sriharsha; Wenny, Brian

    2012-01-01

    The MODerate-resolution Imaging Spectroradiometer (MODIS) is one of the primary instruments in the NASA Earth Observing System (EOS). The first MODIS instrument was launched in December, 1999 on-board the Terra spacecraft. MODIS has 36 bands, covering a wavelength range from 0.4 micron to 14.4 micron. MODIS band 27 (6.72 micron) is a water vapor band, which is designed to be insensitive to Earth surface features. In recent Earth View (EV) images of Terra band 27, surface feature contamination is clearly seen and striping has become very pronounced. In this paper, it is shown that band 27 is impacted by electronic crosstalk from bands 28-30. An algorithm using a linear approximation is developed to correct the crosstalk effect. The crosstalk coefficients are derived from Terra MODIS lunar observations. They show that the crosstalk is strongly detector dependent and the crosstalk pattern has changed dramatically since launch. The crosstalk contributions are positive to the instrument response of band 27 early in the mission but became negative and much larger in magnitude at later stages of the mission for most detectors of the band. The algorithm is applied to both Black Body (BB) calibration and MODIS L1B products. With the crosstalk effect removed, the calibration coefficients of Terra MODIS band 27 derived from the BB show that the detector differences become smaller. With the algorithm applied to MODIS L1B products, the Earth surface features are significantly removed and the striping is substantially reduced in the images of the band. The approach developed in this report for removal of the electronic crosstalk effect can be applied to other MODIS bands if similar crosstalk behaviors occur.

  3. Selective hydrogenation of phenol to cyclohexanone over Pd@CN (N-doped porous carbon): Role of catalyst reduction method

    Science.gov (United States)

    Hu, Shuo; Yang, Guangxin; Jiang, Hong; Liu, Yefei; Chen, Rizhi

    2018-03-01

    Selective phenol hydrogenation is a green and sustainable technology to produce cyclohexanone. The work focused on investigating the role of catalyst reduction method in the liquid-phase phenol hydrogenation to cyclohexanone over Pd@CN (N-doped porous carbon). A series of reduction methods including flowing hydrogen reduction, in-situ reaction reduction and liquid-phase reduction were designed and performed. The results highlighted that the reduction method significantly affected the catalytic performance of Pd@CN in the liquid-phase hydrogenation of phenol to cyclohexanone, and the liquid-phase reduction with the addition of appropriate amount of phenol was highly efficient to improve the catalytic activity of Pd@CN. The influence mechanism was explored by a series of characterizations. The results of TEM, XPS and CO chemisorption confirmed that the reduction method mainly affected the size, surface composition and dispersion of Pd in the CN material. The addition of phenol during the liquid-phase reduction could inhibit the aggregation of Pd NPs and promote the reduction of Pd (2+), and then improved the catalytic activity of Pd@CN. The work would aid the development of high-performance Pd@CN catalysts for selective phenol hydrogenation.

  4. Efficient adsorption of Au(CN)2- from gold cyanidation with graphene oxide-polyethylenimine hydrogel as adsorbent

    Science.gov (United States)

    Yang, Lang; Jia, Feifei; Yang, Bingqiao; Song, Shaoxian

    The adsorption of gold cyanide complex ion (Au(CN)2-) on graphene oxide-polyethylenimine hydrogel (GO/PEI hydrogel) from gold cyanidation has been studied to explore the possibility of the application of GO/PEI hydrogel in gold cyanidation process for extracting gold from ores. The adsorption was carried out in artificial Au(CN)2- aqueous solution with GO/PEI hydrogel as adsorbent. The experimental results, as well as IR, XPS and SEM-EDS, have shown that GO/PEI hydrogel exhibited a high adsorption capacity and a fast adsorption rate of Au(CN)2-, suggesting that GO/PEI hydrogel might be a good adsorbent for the recovery of Au(CN)2-. The adsorption of Au(CN)2- on GO/PEI hydrogel obeyed the Langmuir isotherm model and fitted well with the pseudo second order model. The good recovery of Au(CN)2- was largely related to the porous structure, large specific surface area, as well as the oxygenous functional groups on the surface of GO/PEI hydrogel.

  5. A single optical sensor with high sensitivity for detection of Fe{sup 3+} and CN{sup −} ions

    Energy Technology Data Exchange (ETDEWEB)

    Afshani, Jafar [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Badiei, Alireza, E-mail: abadiei@khayam.ut.ac.ir [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Nanobiomedicine Center of Excellence, Nanoscience and Nanotechnology Research Center, University of Tehran, Tehran (Iran, Islamic Republic of); Jafari, Maryam; Shayesteh, Alireza; Karimi, Mehdi; Lashgari, Negar [School of Chemistry, College of Science, University of Tehran, Tehran (Iran, Islamic Republic of); Mohammadi Ziarani, Ghodsi [Department of Chemistry, Alzahra University, Tehran (Iran, Islamic Republic of)

    2016-11-15

    1,2-Bis(2-hydroxymethylphenoxy)ethane was synthesized and characterized by FT-IR and {sup 1}H NMR spectroscopy, and single crystal X-ray diffraction method. The sensing ability of the sensor was studied in the presence of different cations and anions. Following the excitation wavelengths at 275 nm in EtOH/H{sub 2}O (1:9, v/v) and 310 nm in MeCN/H{sub 2}O (1:9, v/v), two distinct emissions at 305 and 356 nm were obtained, respectively. Fe{sup 3+} and CN{sup −} ions were successfully detected in EtOH/H{sub 2}O and MeCN/H{sub 2}O mixtures, respectively. While the fluorescence intensity of the sensor quenched considerably in the presence of Fe{sup 3+} cation at 305 nm, it enhanced in the presence of CN{sup −} anion at 356 nm. Selectivity of the sensor toward these ions was verified in the presence of a variety of common interfering ions. The detection limits of Fe{sup 3+} and CN{sup −} were calculated as 5.4 × 10{sup −9} mol L{sup −1} and 1.9 × 10{sup −8} mol L{sup −1}, respectively which shows the high sensitivity of the sensor toward the target ions. Finally, the interaction of the sensor and CN{sup −} anion was determined by computational studies.

  6. SFG experiment and ab initio study of the chemisorption of CN - on low-index platinum surfaces

    Science.gov (United States)

    Tadjeddine, M.; Flament, J.-P.; Le Rille, A.; Tadjeddine, A.

    2006-05-01

    A dual analysis is proposed in order to have a better understanding of the adsorption of the cyanide ions on a platinum electrode. The SFG (Sum Frequency Generation) spectroscopy allows the in situ vibrational study and the SFG spectra of the CN - species adsorbed on single crystal Pt electrode allow a systematic study of the low-index platinum surfaces. This experimental work is supported by ab initio calculations using density functional theory and cluster models. For each surface orientation and each geometry, a cluster model of 20-30 Pt atoms has been built in order to interpret the chemisorption of the CN - ions through four kinds of adsorption geometry: on-top or bridge site, bonding via C or N atoms. Geometries have been optimized and adsorption energies, electronic properties and vibrational frequencies have been computed. From the electronic properties, we can propose an analysis of the bonding mechanism for each studied kind of adsorption. The SFG spectra of the CN -/Pt(1 1 1) system present an unique resonance owing to the top C adsorption. It is mainly the same for the CN -/Pt(1 0 0) system. It is also the case for the SFG spectra of the CN -/Pt(1 1 0) system recorded at negative electrochemical voltage; at more positive voltage, a second resonance appears at a lower frequency, owing to the top N adsorption. Experimental and theoretical values of the C-N stretching frequencies are in excellent agreement.

  7. Report from the banding lab

    Science.gov (United States)

    Tautin, J.

    1995-01-01

    Mr. Tautin reported on the seemingly everchanging structure of biological science units within the Interior Department. Current Congressional proposals would either change the name of the Bird Banding Lab's parent agency or make it part of the Geological Survey. The current Congress has not looked favorably on science budgets within the Interior Department, and the Banding Lab's budget is being squeezed ever tighter.

  8. Microscopic modeling of photoluminescence of strongly disordered semiconductors

    International Nuclear Information System (INIS)

    Bozsoki, P.; Kira, M.; Hoyer, W.; Meier, T.; Varga, I.; Thomas, P.; Koch, S.W.

    2007-01-01

    A microscopic theory for the luminescence of ordered semiconductors is modified to describe photoluminescence of strongly disordered semiconductors. The approach includes both diagonal disorder and the many-body Coulomb interaction. As a case study, the light emission of a correlated plasma is investigated numerically for a one-dimensional two-band tight-binding model. The band structure of the underlying ordered system is assumed to correspond to either a direct or an indirect semiconductor. In particular, luminescence and absorption spectra are computed for various levels of disorder and sample temperature to determine thermodynamic relations, the Stokes shift, and the radiative lifetime distribution

  9. Dual-band infrared camera

    Science.gov (United States)

    Vogel, H.; Schlemmer, H.

    2005-10-01

    Every year, numerous accidents happen on European roads due to bad visibility (fog, night, heavy rain). Similarly, the dramatic aviation accidents of year 2001 in Milan and Zurich have reminded us that aviation safety is equally affected by reduced visibility. A dual-band thermal imager was developed in order to raise human situation awareness under conditions of reduced visibility especially in the automotive and aeronautical context but also for all transportation or surveillance tasks. The chosen wavelength bands are the Short Wave Infrared SWIR and the Long Wave Infrared LWIR band which are less obscured by reduced visibility conditions than the visible band. Furthermore, our field tests clearly show that the two different spectral bands very often contain complementary information. Pyramidal fusion is used to integrate complementary and redundant features of the multi-spectral images into a fused image which can be displayed on a monitor to provide more and better information for the driver or pilot.

  10. Quantum electrodynamics of strong fields

    International Nuclear Information System (INIS)

    Greiner, W.

    1983-01-01

    Quantum Electrodynamics of Strong Fields provides a broad survey of the theoretical and experimental work accomplished, presenting papers by a group of international researchers who have made significant contributions to this developing area. Exploring the quantum theory of strong fields, the volume focuses on the phase transition to a charged vacuum in strong electric fields. The contributors also discuss such related topics as QED at short distances, precision tests of QED, nonperturbative QCD and confinement, pion condensation, and strong gravitational fields In addition, the volume features a historical paper on the roots of quantum field theory in the history of quantum physics by noted researcher Friedrich Hund

  11. Instabilities in strongly coupled plasmas

    CERN Document Server

    Kalman, G J

    2003-01-01

    The conventional Vlasov treatment of beam-plasma instabilities is inappropriate when the plasma is strongly coupled. In the strongly coupled liquid state, the strong correlations between the dust grains fundamentally affect the conditions for instability. In the crystalline state, the inherent anisotropy couples the longitudinal and transverse polarizations, and results in unstable excitations in both polarizations. We summarize analyses of resonant and non-resonant, as well as resistive instabilities. We consider both ion-dust streaming and dust beam-plasma instabilities. Strong coupling, in general, leads to an enhancement of the growth rates. In the crystalline phase, a resonant transverse instability can be excited.

  12. ArcCN-Runoff: An ArcGIS tool for generating curve number and runoff maps

    Science.gov (United States)

    Zhan, X.; Huang, M.-L.

    2004-01-01

    The development and the application of ArcCN-Runoff tool, an extension of ESRI@ ArcGIS software, are reported. This tool can be applied to determine curve numbers and to calculate runoff or infiltration for a rainfall event in a watershed. Implementation of GIS techniques such as dissolving, intersecting, and a curve-number reference table improve efficiency. Technical processing time may be reduced from days, if not weeks, to hours for producing spatially varied curve number and runoff maps. An application example for a watershed in Lyon County and Osage County, Kansas, USA, is presented. ?? 2004 Elsevier Ltd. All rights reserved.

  13. Wind-induced response of CN-Tower: comparison of model and full scale

    International Nuclear Information System (INIS)

    Monbaliu, J.; Ruigrok, C.; Isyumov, N.

    1985-01-01

    The approximately 555-m high CN Communications Tower in Toronto has now been operational for nearly a decade. The action of wind on this tower was extensively tested at the Boundary Layer Wind Tunnel Laboratory during the design of the tower. This study provided information on the overall wind loads and responses of the structure, the action of wind on various components, and its effects on the tower performance including transmission quality. A program of monitoring and recording the wind induced response and various meteorological data was started in 1977. This paper presents some results of that program and makes comparisons with wind tunnel model data. (author)

  14. C/N and other Elemental Ratios of Chondritic Porous IDPS and a Fluffy Concordia Micrometeorite

    Science.gov (United States)

    Smith, T.; Nakamura-Messenger, K.; Messenger, S.; Keller, L. P.; Khodja, H.; Raepsaet, C.; Wirick, S.; Flynn, G. J.; Taylor, S.; Engrand, C.; hide

    2013-01-01

    Chondritic porous interplanetary dust particles (CP-IDPs) may be cometary in origin [1], as may ultracarbona-ceous (UCAMMs) [2] and 'fluffy' [3] micrometeorites from the Concordia collection. They are all rich in organics, which can rim grains and may have helped glue grains together during accretion [4]. The organics also contain nitrogen the input of which to Earth has potential biological importance. We report C/N ratios, and other properties of CP-IDPs and a Concordia fluffy microme-teorite.

  15. Scaling analysis of [Fe(pyrazole)4]2[Nb(CN)8] molecular magnet

    Science.gov (United States)

    Konieczny, P.; Pełka, R.; Zieliński, P. M.; Pratt, F. L.; Pinkowicz, D.; Sieklucka, B.; Wasiutyński, T.

    2013-10-01

    The critical behaviour of the three dimensional (3D) molecular magnet {[FeII(pirazol)4]2[NbIV(CN)8]·4H2O}n has been studied with the use of experimental techniques such as ac magnetometry and zero field μSR spectroscopy. The sample orders magnetically below Tc=7.8 K. The measurements allowed to determine static exponents β, γ, and the dynamic exponent w. The resulting exponent values indicate that the studied system belongs to the universality class of the 3D Heisenberg model.

  16. Abrikosov flux-lines in two-band superconductors with mixed dimensionality

    International Nuclear Information System (INIS)

    Tanaka, K; Eschrig, M

    2009-01-01

    We study vortex structure in a two-band superconductor, in which one band is ballistic and quasi-two-dimensional (2D), and the other is diffusive and three-dimensional (3D). A circular cell approximation of the vortex lattice within the quasiclassical theory of superconductivity is applied to a recently developed model appropriate for such a two-band system (Tanaka et al 2006 Phys. Rev. B 73 220501(R); Tanaka et al 2007 Phys. Rev. B 75 214512). We assume that superconductivity in the 3D diffusive band is 'weak', i.e. mostly induced, as is the case in MgB 2 . Hybridization with the 'weak' 3D diffusive band has significant and intriguing influence on the electronic structure of the 'strong' 2D ballistic band. In particular, the Coulomb repulsion and the diffusivity in the 'weak' band enhance suppression of the order parameter and enlargement of the vortex core by magnetic field in the 'strong' band, resulting in reduced critical temperature and field. Moreover, increased diffusivity in the 'weak' band can result in an upward curvature of the upper critical field near the transition temperature. A particularly interesting feature found in our model is the appearance of additional bound states at the gap edge in the 'strong' ballistic band, which are absent in the single-band case. Furthermore, coupling with the 'weak' diffusive band leads to reduced bandgaps and van Hove singularities of energy bands of the vortex lattice in the 'strong' ballistic band. We find these intriguing features for parameter values appropriate for MgB 2 .

  17. SINGLE-BAND, TRIPLE-BAND, OR MULTIPLE-BAND HUBBARD MODELS

    NARCIS (Netherlands)

    ESKES, H; SAWATZKY, GA

    1991-01-01

    The relevance of different models, such as the one-band t-J model and the three-band Emery model, as a realistic description of the electronic structure of high-T(c) materials is discussed. Starting from a multiband approach using cluster calculations and an impurity approach, the following

  18. Short proofs of strong normalization

    OpenAIRE

    Wojdyga, Aleksander

    2008-01-01

    This paper presents simple, syntactic strong normalization proofs for the simply-typed lambda-calculus and the polymorphic lambda-calculus (system F) with the full set of logical connectives, and all the permutative reductions. The normalization proofs use translations of terms and types to systems, for which strong normalization property is known.

  19. Characterization of the corrosion behavior of an austenitic stainless steel for biomedical applications coated with Ti N, Ti CN And DLC PVD coatings

    International Nuclear Information System (INIS)

    Antunes, Renato Altobelli

    2006-01-01

    Metallic biomaterials must present a combination of properties such as corrosion resistance, biocompatibility and mechanical resistance. Austenitic stainless steels, especially AISI 316L combine these properties with the easy of fabrication at low cost. However, they are prone to corrosion in physiological solutions. Furthermore, their corrosion products may lead to infectious ou allergenic reactions in the tissues around the implant device. In the present work, coatings produced by physical vapour deposition (PVD) methods have been applied on the surface of a 316L stainless steel to increase its corrosion resistance and biocompatibility. Three thin films were tested: titanium nitride (TiN), titanium carbonitride (TiCN) and diamond-like carbon (DLC). These materials present high hardness, wear resistance and intrinsic biocompatibility that are key features when considering biomedical applications. The characterization of the electrochemical behavior of the stainless steel coated with the three different films showed that the presence of surface defects are deleterious to the corrosion resistance of the substrate. These defects were observed using scanning electron microscopy. The evolution of the electrochemical behavior of the coated steel was explained through a mechanism based on the experimental results obtained using electrochemical impedance spectroscopy. Two different passivation treatments were carried out on the stainless steel surface, either in sulfuric or nitric acid solutions, to increase its corrosion resistance. The results suggested que these treatments were not efficient, but may be modified to improve its performance. The electronic properties of the passive films of the non-passivated and passivated stainless steel were studied using the Mott-Schottky approach. The films presented a duplex character. Below the flat band potential the behavior is typical of a highly doped type-p semiconductor. Above the flat band potential is typical of a highly

  20. Complex organic molecules in strongly UV-irradiated gas

    Science.gov (United States)

    Cuadrado, S.; Goicoechea, J. R.; Cernicharo, J.; Fuente, A.; Pety, J.; Tercero, B.

    2017-07-01

    We investigate the presence of complex organic molecules (COMs) in strongly UV-irradiated interstellar molecular gas. We have carried out a complete millimetre (mm) line survey using the IRAM 30 m telescope towards the edge of the Orion Bar photodissociation region (PDR), close to the H2 dissociation front, a position irradiated by a very intense far-UV (FUV) radiation field. These observations have been complemented with 8.5'' resolution maps of the H2CO JKa,Kc = 51,5 → 41,4 and C18O J = 3 → 2 emission at 0.9 mm. Despite being a harsh environment, we detect more than 250 lines from COMs and related precursors: H2CO, CH3OH, HCO, H2CCO, CH3CHO, H2CS, HCOOH, CH3CN, CH2NH, HNCO, H213CO, and HC3N (in decreasing order of abundance). For each species, the large number of detected lines allowed us to accurately constrain their rotational temperatures (Trot) and column densities (N). Owing to subthermal excitation and intricate spectroscopy of some COMs (symmetric- and asymmetric-top molecules such as CH3CN and H2CO, respectively), a correct determination of N and Trot requires building rotational population diagrams of their rotational ladders separately. The inferred column densities are in the 1011-1013 cm-2 range. We also provide accurate upper limit abundances for chemically related molecules that might have been expected, but are not conclusively detected at the edge of the PDR (HDCO, CH3O, CH3NC, CH3CCH, CH3OCH3, HCOOCH3, CH3CH2OH, CH3CH2CN, and CH2CHCN). A non-thermodynamic equilibrium excitation analysis for molecules with known collisional rate coefficients suggests that some COMs arise from different PDR layers but we cannot resolve them spatially. In particular, H2CO and CH3CN survive in the extended gas directly exposed to the strong FUV flux (Tk = 150-250 K and Td≳ 60 K), whereas CH3OH only arises from denser and cooler gas clumps in the more shielded PDR interior (Tk = 40-50 K). The non-detection of HDCO towards the PDR edge is consistent with the

  1. Strong-back safety latch

    International Nuclear Information System (INIS)

    DeSantis, G.N.

    1995-01-01

    The calculation decides the integrity of the safety latch that will hold the strong-back to the pump during lifting. The safety latch will be welded to the strong-back and will latch to a 1.5-in. dia cantilever rod welded to the pump baseplate. The static and dynamic analysis shows that the safety latch will hold the strong-back to the pump if the friction clamps fail and the pump become free from the strong-back. Thus, the safety latch will meet the requirements of the Lifting and Rigging Manual for under the hook lifting for static loading; it can withstand shock loads from the strong-back falling 0.25 inch

  2. Estimating Composite Curve Number Using an Improved SCS-CN Method with Remotely Sensed Variables in Guangzhou, China

    Directory of Open Access Journals (Sweden)

    Qihao Weng

    2013-03-01

    Full Text Available The rainfall and runoff relationship becomes an intriguing issue as urbanization continues to evolve worldwide. In this paper, we developed a simulation model based on the soil conservation service curve number (SCS-CN method to analyze the rainfall-runoff relationship in Guangzhou, a rapid growing metropolitan area in southern China. The SCS-CN method was initially developed by the Natural Resources Conservation Service (NRCS of the United States Department of Agriculture (USDA, and is one of the most enduring methods for estimating direct runoff volume in ungauged catchments. In this model, the curve number (CN is a key variable which is usually obtained by the look-up table of TR-55. Due to the limitations of TR-55 in characterizing complex urban environments and in classifying land use/cover types, the SCS-CN model cannot provide more detailed runoff information. Thus, this paper develops a method to calculate CN by using remote sensing variables, including vegetation, impervious surface, and soil (V-I-S. The specific objectives of this paper are: (1 To extract the V-I-S fraction images using Linear Spectral Mixture Analysis; (2 To obtain composite CN by incorporating vegetation types, soil types, and V-I-S fraction images; and (3 To simulate direct runoff under the scenarios with precipitation of 57mm (occurred once every five years by average and 81mm (occurred once every ten years. Our experiment shows that the proposed method is easy to use and can derive composite CN effectively.

  3. Evaluation of soil loss estimation using the RUSLE model and SCS-CN method in hillslope mining areas

    Directory of Open Access Journals (Sweden)

    Narayan Kayet

    2018-03-01

    Full Text Available Mining operations result in the generation of barren land and spoil heaps which are subject to high erosion rate during the rainy season. The present study uses the Revised Universal Soil Loss Equation (RUSLE and SCS-CN (Soil Conservation Service - Curve Number process to estimate in Kiruburu and Meghahatuburu mining sites areas. The geospatial model of annual average soil loss rate was determined by integrating environmental variables parameters in a raster pixels-based GIS framework. GIS layers with, rainfall passivity and runoff erosivity (R, soil erodibility (K, slope length and steepness (LS, cover management(C and conservation practice (P factors were calculated to determine their effects on annual soil erosion in the study area. The coefficient of determination (r2 was 0.834, which indicates a strong correlation of soil loss with runoff and rainfall. Sub -watersheds 5,9,10 and 2 experienced high level of highly runoff. Average annual soil loss was calculated (30*30 m raster grid cell to determine the critical soil loss areas (Sub-watershed 9 and 5. Total soil erosion area was classified into five class, slight (10,025 ha, moderate (3125 ha, high (973 ha, very high (260 ha and severe (53 ha. The resulting map shows greatest soil erosion of >40 t h-1 y-1 (severe through connection to grassland, degraded and open forestry on the erect mining side-escutcheon. The Landsat pan sharpening image and DGPS survey field data were used in the verification of soil erosion results.

  4. Post-transition state dynamics and product energy partitioning following thermal excitation of the F⋯HCH2CN transition state: Disagreement with experiment

    Science.gov (United States)

    Pratihar, Subha; Ma, Xinyou; Xie, Jing; Scott, Rebecca; Gao, Eric; Ruscic, Branko; Aquino, Adelia J. A.; Setser, Donald W.; Hase, William L.

    2017-10-01

    Born-Oppenheimer direct dynamics simulations were performed to study atomistic details of the F + CH3CN → HF + CH2CN H-atom abstraction reaction. The simulation trajectories were calculated with a combined M06-2X/MP2 algorithm utilizing the 6-311++G** basis set. The experiments were performed at 300 K, and assuming the accuracy of transition state theory (TST), the trajectories were initiated at the F⋯HCH2CN abstraction TS with a 300 K Boltzmann distribution of energy and directed towards products. Recrossing of the TS was negligible, confirming the accuracy of TST. HF formation was rapid, occurring within 0.014 ps of the trajectory initiation. The intrinsic reaction coordinate (IRC) for reaction involves rotation of HF about CH2CN and then trapping in the CH2CN⋯HF post-reaction potential energy well of ˜10 kcal/mol with respect to the HF + CH2CN products. In contrast to this IRC, five different trajectory types were observed: the majority proceeded by direct H-atom transfer and only 11% approximately following the IRC. The HF vibrational and rotational quantum numbers, n and J, were calculated when HF was initially formed and they increase as potential energy is released in forming the HF + CH2CN products. The population of the HF product vibrational states is only in qualitative agreement with experiment, with the simulations showing depressed and enhanced populations of the n = 1 and 2 states as compared to experiment. Simulations with an anharmonic zero-point energy constraint gave product distributions for relative translation, HF rotation, HF vibration, CH2CN rotation, and CH2CN vibration as 5%, 11%, 60%, 7%, and 16%, respectively. In contrast, the experimental energy partitioning percentages to HF rotation and vibration are 6% and 41%. Comparisons are made between the current simulation and those for other F + H-atom abstraction reactions. The simulation product energy partitioning and HF vibrational population for F + CH3CN → HF + CH2CN

  5. Statistical optimization of fermentative hydrogen production from xylose by newly isolated Enterobacter sp. CN1

    Energy Technology Data Exchange (ETDEWEB)

    Long, Chuannan; Cui, Jingjing; Liu, Zuotao; Liu, Yuntao; Hu, Zhong [Department of Biology, Shantou University, Shantou 515063 (China); Long, Minnan [The School of Energy Research, Xiamen University, Xiamen 361005 (China)

    2010-07-15

    Statistical experimental designs were applied for the optimization of medium constituents for hydrogen production from xylose by newly isolated Enterobacter sp. CN1. Using Plackett-Burman design, xylose, FeSO{sub 4} and peptone were identified as significant variables which highly influenced hydrogen production. The path of steepest ascent was undertaken to approach the optimal region of the three significant factors. These variables were subsequently optimized using Box-Behnken design of response surface methodology (RSM). The optimum conditions were found to be xylose 16.15 g/L, FeSO{sub 4} 250.17 mg/L, peptone 2.54 g/L. Hydrogen production at these optimum conditions was 1149.9 {+-} 65 ml H{sub 2}/L medium. Under different carbon sources condition, the cumulative hydrogen volume were 1217 ml H{sub 2}/L xylose medium, 1102 ml H{sub 2}/L glucose medium and 977 ml H{sub 2}/L sucrose medium; the maximum hydrogen yield were 2.0 {+-} 0.05 mol H{sub 2}/mol xylose, 0.64 mol H{sub 2}/mol glucose. Fermentative hydrogen production from xylose by Enterobacter sp. CN1 was superior to glucose and sucrose. (author)

  6. Anomalous cosmic ray carbon and oxygen tracks in CN-Kodak.

    Science.gov (United States)

    Kondratyeva, M A; Tretyakova, C A; Tretyakova, S P; Zhuravlev, D A

    2001-06-01

    For observation of low energy cosmic ray particles we used CN-Kodak nuclear track detectors on Cosmos satellites. In solar quiet periods during solar minima conditions the detectors registered anomalous cosmic rays (ACRs). The ACRs are characterized by flux enhancements of several elements and it is known that the carbon enhancement is small compared with that of oxygen. In all of our quiet-time exposures the relation between carbon and oxygen was extremely small (C/O ~ 0.03). But in two quiet-time periods of 14.03.96-11.06.96 and of 15.12.97-14.04.98 we have identified many tracks as carbon in a L-R diagram. As a result the observed C/O ratio appears to be more than 0.5, whereas other experiments show no evidence of enhanced flux of carbon during these periods. The reason for the unexpected response of CN-Kodak is discussed. c2001 Elsevier Science Ltd. All rights reserved.

  7. Preparation and Characterization of SiO2/SiCN Core-shell Ceramic Microspheres

    Directory of Open Access Journals (Sweden)

    ZHANG Hai-yuan

    2017-05-01

    Full Text Available The SiO2/PSN core-shell microspheres were prepared via an emulsion reaction combined with the polymer-derived ceramics (PDCs method using polysilazane (PSN in situ polymerization on the surface of SiO2 modified by silane coupling agents MPS, followed by pyrolysis process to obtain SiO2/SiCN core-shell ceramic microspheres. The effects of raw mass ratio, curing time and pyrolysis temperature on the formation and the morphology of core-shell microspheres were studied. The morphology, chemical composition and phase transformation were characterized by SEM, EDS, TEM, FT-IR and XRD. The results show that after reaction for 4h at 200℃, SiO2 completely coated PSN forms a core-shell microsphere with rough surface when the mass ratio of SiO2 and PSN is 1:4; when pyrolysis temperature is at 800-1200℃, amorphous SiO2/SiCN core-shell ceramic microspheres are prepared; at 1400℃, the amorphous phase partially crystallizes to produce SiO2, SiC and Si3N4 phase.

  8. Alkyl hydrogen atom abstraction reactions of the CN radical with ethanol

    Science.gov (United States)

    Athokpam, Bijyalaxmi; Ramesh, Sai G.

    2018-04-01

    We present a study of the abstraction of alkyl hydrogen atoms from the β and α positions of ethanol by the CN radical in solution using the Empirical Valence Bond (EVB) method. We have built separate 2 × 2 EVB models for the Hβ and Hα reactions, where the atom transfer is parameterized using ab initio calculations. The intra- and intermolecular potentials of the reactant and product molecules were modelled with the General AMBER Force Field, with some modifications. We have carried out the dynamics in water and chloroform, which are solvents of contrasting polarity. We have computed the potential of mean force for both abstractions in each of the solvents. They are found to have a small and early barrier along the reaction coordinate with a large energy release. Analyzing the solvent structure around the reaction system, we have found two solvents to have little effect on either reaction. Simulating the dynamics from the transition state, we also study the fate of the energies in the HCN vibrational modes. The HCN molecule is born vibrationally hot in the CH stretch in both reactions and additionally in the HCN bends for the Hα abstraction reaction. In the early stage of the dynamics, we find that the CN stretch mode gains energy at the expense of the energy in CH stretch mode.

  9. A combined crossed molecular beams and theoretical study of the reaction CN + C2H4

    International Nuclear Information System (INIS)

    Balucani, Nadia; Leonori, Francesca; Petrucci, Raffaele; Wang, Xingan; Casavecchia, Piergiorgio; Skouteris, Dimitrios; Albernaz, Alessandra F.; Gargano, Ricardo

    2015-01-01

    Highlights: • The CN + C 2 H 4 reaction was investigated in crossed beam experiments. • Electronic structure calculations of the potential energy surface were performed. • RRKM estimates qualitatively reproduce the experimental C 2 H 3 NC yield. - Abstract: The CN + C 2 H 4 reaction has been investigated experimentally, in crossed molecular beam (CMB) experiments at the collision energy of 33.4 kJ/mol, and theoretically, by electronic structure calculations of the relevant potential energy surface and Rice–Ramsperger–Kassel–Marcus (RRKM) estimates of the product branching ratio. Differently from previous CMB experiments at lower collision energies, but similarly to a high energy study, we have some indication that a second reaction channel is open at this collision energy, the characteristics of which are consistent with the channel leading to CH 2 CHNC + H. The RRKM estimates using M06L electronic structure calculations qualitatively support the experimental observation of C 2 H 3 NC formation at this and at the higher collision energy of 42.7 kJ/mol of previous experiments

  10. Static Recrystallization Behavior of Z12CN13 Martensite Stainless Steel

    Science.gov (United States)

    Luo, Min; Zhou, Bing; Li, Rong-bin; Xu, Chun; Guo, Yan-hui

    2017-09-01

    In order to increase the hot workability and provide proper hot forming parameters of forging Z12CN13 martensite stainless steel for the simulation and production, the static recrystallization behavior has been studied by double-pass hot compression tests. The effects of deformation temperature, strain rate and inter-pass time on the static recrystallization fraction by the 2% offset method are extensively studied. The results indicate that increasing the inter-pass time and the deformation temperature as well as strain rate appropriately can increase the fraction of static recrystallization. At the temperature of 1050-1150 °C, inter-pass time of 30-100 s and strain rate of 0.1-5 s-1, the static recrystallization behavior is obvious. In addition, the kinetics of static recrystallization behavior of Z12CN13 steel has been established and the activation energy of static recrystallization is 173.030 kJ/mol. The substructure and precipitates have been studied by TEM. The results reveal that the nucleation mode is bulging at grain boundary. Undissolved precipitates such as MoNi3 and Fe3C have a retarding effect on the recrystallization kinetics. The effect is weaker than the accelerating effect of deformation temperature.

  11. Numerical analysis of heat treatment of TiCN coated AA7075 aluminium alloy

    Science.gov (United States)

    Srinath, M. K.; Prasad, M. S. Ganesha

    2018-04-01

    The Numerical analysis of heat treatments of TiCN coated AA7075 aluminium alloys is presented in this paper. The Convection-Diffusion-Reaction (CDR) equation with solutions in the Streamlined-Upward Petrov-Galerkin (SUPG) method for different parameters is provided for the understanding of the process. An experimental process to improve the surface properties of AA-7075 aluminium alloy was attempted through the coatings of TiCN and subsequent heat treatments. From the experimental process, optimized temperature and time was obtained which gave the maximum surface hardness and corrosion resistance. The paper gives an understanding and use of the CDR equation for application of the process. Expression to determine convection, diffusion and reaction parameters are provided which is used to obtain the overall expression of the heat treatment process. With the substitution of the optimized temperature and time, the governing equation may be obtained. Additionally, the total energy consumed during the heat treatment process is also developed to give a mathematical formulation of the energy consumed.

  12. Surface modification of an aluminum alloy by electron beam introducing TiCN nanoparticles

    Science.gov (United States)

    Kolev, M.; Dimitrova, R.; Parshorov, St.; Valkov, St.; Lazarova, R.; Petrov, P.

    2018-03-01

    TiCN nanopowder deposited in an appropriate way on the surface of an AlSi12Cu2NiMg substrate was incorporated in the matrix using an electron beam technology. The samples were studied by means of light microscopy, SEM, and EDX; their microhardness was also determined. The formation was found of a uniform and dense coating with a thickness of 7 – 10 μgm with a good adherence to the substrate. A modified zone appeared under the coating with a thickness of 100 – 150 μgm containing dendrites of an α-solid solution and a fine eutectic between them, as well as primary silicon crystals. The microhardness of this modified zone was up to 2.4 times higher than that of the matrix. The results of SEM and EDX studies revealed unambiguously the presence of titanium in the coating and in the zones below it. Obviously, the electron beam treatment resulted in the TiCN nanoparticles penetrating into the coating and the substrate immediately below the coating.

  13. A CN-Based Ensembled Hydrological Model for Enhanced Watershed Runoff Prediction

    Directory of Open Access Journals (Sweden)

    Muhammad Ajmal

    2016-01-01

    Full Text Available A major structural inconsistency of the traditional curve number (CN model is its dependence on an unstable fixed initial abstraction, which normally results in sudden jumps in runoff estimation. Likewise, the lack of pre-storm soil moisture accounting (PSMA procedure is another inherent limitation of the model. To circumvent those problems, we used a variable initial abstraction after ensembling the traditional CN model and a French four-parameter (GR4J model to better quantify direct runoff from ungauged watersheds. To mimic the natural rainfall-runoff transformation at the watershed scale, our new parameterization designates intrinsic parameters and uses a simple structure. It exhibited more accurate and consistent results than earlier methods in evaluating data from 39 forest-dominated watersheds, both for small and large watersheds. In addition, based on different performance evaluation indicators, the runoff reproduction results show that the proposed model produced more consistent results for dry, normal, and wet watershed conditions than the other models used in this study.

  14. Development of the dyed-track method for Kodak CN-85 detector. No. E/3

    International Nuclear Information System (INIS)

    Somogyi, G.; Toth-Szilagyi, M.; Varga, Zs.; Monnin, M.; Lferde, M.

    1983-01-01

    The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, coloration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In the authors' previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work the influence of track processing parameters on the dyed-track formation was studied in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particles irradiation. For sensitization a treatment with 15% HCL at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be best. For understanding the track dyeing phenomenon the coloration behaviour of electron-irradiated CN-85 detectors was studied. (author)

  15. Development of the dyed-track method for Kodak CN-85 detector

    International Nuclear Information System (INIS)

    Somogyi, G.; Toth-Szilagyi, M.; Varga, Z.; Monnin, M.; Lferde, M.

    1984-01-01

    The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, colouration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In our previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work we have studied the influence of track processing parameters on the dyed-track formation in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particle irradiation. For sensitization a treatment with 15% HCl at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be the best. For better understanding the track dyeing phenomenon we have studied the colouration behaviour of electron-irradiated CN-85 detectors. (author)

  16. Development of the dyed-track method for Kodak CN-85 detector

    Energy Technology Data Exchange (ETDEWEB)

    Somogyi, G.; Toth-Szilagyi, M.; Varga, Z. (Magyar Tudomanyos Akademia, Debrecen. Atommag Kutato Intezete); Monnin, M.; Lferde, M. (Clermont-Ferrand-2 Univ., 63 - Aubiere (France). Lab. de Physique Corpusculaire)

    1984-01-01

    The dyed-track method has been successfully developed for cellulose derivatives. The track parameters (width, colouration deepness, contrast, registration sensitivity), however, proved to be very dependent on the detector material and on the track processing conditions. In our previous works optimum conditions were presented mostly for cellulose acetate sheets. In the present work we have studied the influence of track processing parameters on the dyed-track formation in Kodak cellulose nitrate detector called CN-85. It is found that in this material optimum dyed-tracks can be produced with using no swelling but with a thermal annealing at 100 deg C for 1 hour after particle irradiation. For sensitization a treatment with 15% HCl at 22 deg C for 20 hours and for dyeing 0.3 wt% Rhodamine-B at 100 deg C for 1 hour proved to be the best. For better understanding the track dyeing phenomenon we have studied the colouration behaviour of electron-irradiated CN-85 detectors.

  17. Oxidation Study of an Ultra High Temperature Ceramic Coatings Based on HfSiCN

    Science.gov (United States)

    Sacksteder, Dagny; Waters, Deborah L.; Zhu, Dongming

    2018-01-01

    High temperature fiber-reinforced ceramic matrix composites (CMCs) are important for aerospace applications because of their low density, high strength, and significantly higher-temperature capabilities compared to conventional metallic systems. The use of the SiCf/SiC and Cf/SiC CMCs allows the design of lighter-weight, more fuel efficient aircraft engines and also more advanced spacecraft airframe thermal protection systems. However, CMCs have to be protected with advanced environmental barrier coatings when they are incorporated into components for the harsh environments such as in aircraft engine or spacecraft applications. In this study, high temperature oxidation kinetics of an advanced HfSiCN coating on Cf/SiC CMC substrates were investigated at 1300 C, 1400 C, and 1500 C by using thermogravimetric analysis (TGA). The coating oxidation reaction parabolic rate constant and activation energy were estimated from the experimental results. The oxidation reaction studies showed that the coatings formed the most stable, predominant HfSiO4-HfO2 scales at 1400 C. A peroxidation test at 1400 C then followed by subsequent oxidation tests at various temperatures also showed more adherent scales and slower scale growth because of reduced the initial transient oxidation stage and increased HfSiO4-HfO2 content in the scales formed on the HfSiCN coatings.

  18. Cloning, Expression Profiling and Functional Analysis of CnHMGS, a Gene Encoding 3-hydroxy-3-Methylglutaryl Coenzyme A Synthase from Chamaemelum nobile.

    Science.gov (United States)

    Cheng, Shuiyuan; Wang, Xiaohui; Xu, Feng; Chen, Qiangwen; Tao, Tingting; Lei, Jing; Zhang, Weiwei; Liao, Yongling; Chang, Jie; Li, Xingxiang

    2016-03-08

    Roman chamomile (Chamaemelum nobile L.) is renowned for its production of essential oils, which major components are sesquiterpenoids. As the important enzyme in the sesquiterpenoid biosynthesis pathway, 3-hydroxy-3-methylglutaryl coenzyme A synthase (HMGS) catalyze the crucial step in the mevalonate pathway in plants. To isolate and identify the functional genes involved in the sesquiterpene biosynthesis of C. nobile L., a HMGS gene designated as CnHMGS (GenBank Accession No. KU529969) was cloned from C. nobile. The cDNA sequence of CnHMGS contained a 1377 bp open reading frame encoding a 458-amino-acid protein. The sequence of the CnHMGS protein was highly homologous to those of HMGS proteins from other plant species. Phylogenetic tree analysis revealed that CnHMGS clustered with the HMGS of Asteraceae in the dicotyledon clade. Further functional complementation of CnHMGS in the mutant yeast strain YSC6274 lacking HMGS activity demonstrated that the cloned CnHMGS cDNA encodes a functional HMGS. Transcript profile analysis indicated that CnHMGS was preferentially expressed in flowers and roots of C. nobile. The expression of CnHMGS could be upregulated by exogenous elicitors, including methyl jasmonate and salicylic acid, suggesting that CnHMGS was elicitor-responsive. The characterization and expression analysis of CnHMGS is helpful to understand the biosynthesis of sesquiterpenoid in C. nobile at the molecular level and also provides molecular wealth for the biotechnological improvement of this important medicinal plant.

  19. Quantitative analysis on electric dipole energy in Rashba band splitting.

    Science.gov (United States)

    Hong, Jisook; Rhim, Jun-Won; Kim, Changyoung; Ryong Park, Seung; Hoon Shim, Ji

    2015-09-01

    We report on quantitative comparison between the electric dipole energy and the Rashba band splitting in model systems of Bi and Sb triangular monolayers under a perpendicular electric field. We used both first-principles and tight binding calculations on p-orbitals with spin-orbit coupling. First-principles calculation shows Rashba band splitting in both systems. It also shows asymmetric charge distributions in the Rashba split bands which are induced by the orbital angular momentum. We calculated the electric dipole energies from coupling of the asymmetric charge distribution and external electric field, and compared it to the Rashba splitting. Remarkably, the total split energy is found to come mostly from the difference in the electric dipole energy for both Bi and Sb systems. A perturbative approach for long wave length limit starting from tight binding calculation also supports that the Rashba band splitting originates mostly from the electric dipole energy difference in the strong atomic spin-orbit coupling regime.

  20. Band gap engineering strategy via polarization rotation in perovskite ferroelectrics

    International Nuclear Information System (INIS)

    Wang, Fenggong; Grinberg, Ilya; Rappe, Andrew M.

    2014-01-01

    We propose a strategy to engineer the band gaps of perovskite oxide ferroelectrics, supported by first principles calculations. We find that the band gaps of perovskites can be substantially reduced by as much as 1.2 eV through local rhombohedral-to-tetragonal structural transition. Furthermore, the strong polarization of the rhombohedral perovskite is largely preserved by its tetragonal counterpart. The B-cation off-center displacements and the resulting enhancement of the antibonding character in the conduction band give rise to the wider band gaps of the rhombohedral perovskites. The correlation between the structure, polarization orientation, and electronic structure lays a good foundation for understanding the physics of more complex perovskite solid solutions and provides a route for the design of photovoltaic perovskite ferroelectrics

  1. Effect of conduction band nonparabolicity on the optical properties in ...

    Indian Academy of Sciences (India)

    the bulk conduction band edge, the correction due to nonparabolicity can be important. [9,10]. In a narrow QW under a strong magnetic field, the optical absorption coefficients calculated with the nonparabolicity correction shows remarkable deviation from results obtained using parabolic energy approximation [11].

  2. Mechanical Properties And Microstructure Of AlN/SiCN Nanocomposite Coatings Prepared By R.F.-Reactive Sputtering Method

    Directory of Open Access Journals (Sweden)

    Nakafushi Y.

    2015-06-01

    Full Text Available FIn this work, AlN/SiCN composite coatings were deposited by r.f.-reactive sputtering method using a facing target-type sputtering (FTS apparatus with composite targets consisting of Al plate and SiC chips in a gaseous mixture of Ar and N2, and investigated their mechanical properties and microstructure. The indentation hardness (HIT of AlN/SiCN coatings prepared from composite targets consisting of 8 ~32 chips of SiC and Al plate showed the maximum value of about 29~32 GPa at a proper nitrogen gas flow rate. X-ray diffraction (XRD patterns for the AlN/SiCN composite coatings indicated the presence of the only peeks of hexagonal (B4 structured AlN phase. AlN coatings clarified the columnar structure of the cross sectional view TEM observation. On the other hand, microstructure of AlN/SiCN composite coatings changed from columnar to equiaxed structure with increasing SiCN content. HR-TEM observation clarified that the composite coatings consisted of very fine equiaxial grains of B4 structured AlN phase and amorphous phase.

  3. Structural, Mechanical and Tribological Properties of NbCN-Ag Nanocomposite Films Deposited by Reactive Magnetron Sputtering

    Directory of Open Access Journals (Sweden)

    Fanjing Wu

    2018-01-01

    Full Text Available In this study, reactive magnetron sputtering was applied for preparing NbCN-Ag films with different Ag additions. Ag contents in the as-deposited NbCN-Ag films were achieved by adjusting Ag target power. The composition, microstructure, mechanical properties, and tribological properties were characterized using energy-dispersive X-ray spectroscopy (EDS, X-ray diffraction (XRD, field emission scanning electron microscope (FE-SEM, high resolution transmission electron microscopy (HRTEM, Raman spectrometry, nano-indentation, and high-temperature sliding wear tests. Results indicated that face-centered cubic (fcc NbN, hexagonal close-packed (hcp NbN and fcc Ag, amorphous C and amorphous CNx phase co-existed in the as-deposited NbCN-Ag films. After doping with 2.0 at.% Ag, the hardness and elastic modulus reached a maximum value of 33 GPa and 340 GPa, respectively. Tribological properties were enhanced by adding Ag in NbCN-Ag films at room temperature. When the test temperature rose from 300 to 500 °C, the addition of Ag was found beneficial for the friction properties, showing a lowest friction coefficient of ~0.35 for NbCN-12.9 at.% Ag films at 500 °C. This was mainly attributed to the existence of AgOx, NbOx, and AgNbOx lubrication phases that acted as solid lubricants to modify the wear mechanism.

  4. New Insights into Understanding Irreversible and Reversible Lithium Storage within SiOC and SiCN Ceramics

    Directory of Open Access Journals (Sweden)

    Magdalena Graczyk-Zajac

    2015-02-01

    Full Text Available Within this work we define structural properties of the silicon carbonitride (SiCN and silicon oxycarbide (SiOC ceramics which determine the reversible and irreversible lithium storage capacities, long cycling stability and define the major differences in the lithium storage in SiCN and SiOC. For both ceramics, we correlate the first cycle lithiation or delithiation capacity and cycling stability with the amount of SiCN/SiOC matrix or free carbon phase, respectively. The first cycle lithiation and delithiation capacities of SiOC materials do not depend on the amount of free carbon, while for SiCN the capacity increases with the amount of carbon to reach a threshold value at ~50% of carbon phase. Replacing oxygen with nitrogen renders the mixed bond Si-tetrahedra unable to sequester lithium. Lithium is more attracted by oxygen in the SiOC network due to the more ionic character of Si-O bonds. This brings about very high initial lithiation capacities, even at low carbon content. If oxygen is replaced by nitrogen, the ceramic network becomes less attractive for lithium ions due to the more covalent character of Si-N bonds and lower electron density on the nitrogen atom. This explains the significant difference in electrochemical behavior which is observed for carbon-poor SiCN and SiOC materials.

  5. New Insights into Understanding Irreversible and Reversible Lithium Storage within SiOC and SiCN Ceramics.

    Science.gov (United States)

    Graczyk-Zajac, Magdalena; Reinold, Lukas Mirko; Kaspar, Jan; Sasikumar, Pradeep Vallachira Warriam; Soraru, Gian-Domenico; Riedel, Ralf

    2015-02-24

    Within this work we define structural properties of the silicon carbonitride (SiCN) and silicon oxycarbide (SiOC) ceramics which determine the reversible and irreversible lithium storage capacities, long cycling stability and define the major differences in the lithium storage in SiCN and SiOC. For both ceramics, we correlate the first cycle lithiation or delithiation capacity and cycling stability with the amount of SiCN/SiOC matrix or free carbon phase, respectively. The first cycle lithiation and delithiation capacities of SiOC materials do not depend on the amount of free carbon, while for SiCN the capacity increases with the amount of carbon to reach a threshold value at ~50% of carbon phase. Replacing oxygen with nitrogen renders the mixed bond Si-tetrahedra unable to sequester lithium. Lithium is more attracted by oxygen in the SiOC network due to the more ionic character of Si-O bonds. This brings about very high initial lithiation capacities, even at low carbon content. If oxygen is replaced by nitrogen, the ceramic network becomes less attractive for lithium ions due to the more covalent character of Si-N bonds and lower electron density on the nitrogen atom. This explains the significant difference in electrochemical behavior which is observed for carbon-poor SiCN and SiOC materials.

  6. Influence of trimethylsilane flow on the microstructure, mechanical and tribological properties of CrSiCN coatings in water lubrication

    Science.gov (United States)

    Wu, Zhiwei; Zhou, Fei; Wang, Qianzhi; Zhou, Zhifeng; Yan, Jiwang; Li, Lawrence Kwok-Yan

    2015-11-01

    CrSiCN coatings with different silicon and carbon contents were deposited on silicon wafers and 316L stainless steels using unbalanced magnetron sputtering via adjusting trimethylsilane (TMS) flow, and their microstructure and mechanical properties were characterized by X-ray diffraction (XRD), scanning electron microscopy(SEM), X-ray photoelectrons spectroscopy(XPS) and nano-indenter, respectively. The tribological properties of CrSiCN coatings sliding against SiC balls in water were investigated using ball-on-disk tribometer. The results showed that the CrSiCN coatings had fine composite microstructure consisting of nanocrystallites of Cr(C, N) crystal and amorphous phases such as a-Si3N4 and a-C(a-CNx). The typical columnar structures changed from fine cluster to coarse ones when the Si content was beyond 3.4 at.%. With an increase in the TMS flow, the hardness and Young's modulus of Corsican coatings all first increased, and then rapidly decreased, but the compressive stress in the coatings varied in the range of 2.8-4.8 GPa. When the TMS flow was 10 sccm, the CrSiCN coatings exhibited the highest hardness of 21.3 GPa and the lowest friction coefficient (0.11) and wear rate (8.4 × 10-8 mm3/N m). But when the TMS flow was beyond 15 sccm, the tribological properties of CrSiCN coatings in water became poor.

  7. PREDICTION OF THE SPECTROSCOPIC PARAMETERS OF NEW IRON COMPOUNDS: HYDRIDE OF IRON CYANIDE/ISOCYANIDE, HFeCN/HFeNC

    Energy Technology Data Exchange (ETDEWEB)

    Redondo, Pilar; Barrientos, Carmen; Largo, Antonio, E-mail: predondo@qf.uva.es [Departamento de Química Física y Química Inorgánica Facultad de Ciencias, Universidad de Valladolid Campus Miguel Delibes Paseo de Belén 7, E-47011, Valladolid (Spain)

    2016-09-01

    Iron is the most abundant transition metal in space. Its abundance is similar to that of magnesium, and until today only, FeO and FeCN have been detected. However, magnesium-bearing compounds such as MgCN, MgNC, and HMgNC are found in IRC+10216. It seems that the hydrides of iron cyanide/isocyanide could be good candidates to be present in space. In the present work we carried out a characterization of the different minima on the quintet and triplet [C, Fe, H, N] potential energy surfaces, employing several theoretical approaches. The most stable isomers are predicted to be hydride of iron cyanide HFeCN, and isocyanide HFeNC, in their {sup 5}Δ states. Both isomers are found to be quasi-isoenergetics. The HFeNC isomer is predicted to lie about 0.5 kcal/mol below HFeCN. The barrier for the interconversion process is estimated to be around 6.0 kcal/mol, making this process unfeasible under low temperature conditions, such as those in the interstellar medium. Therefore, both HFeCN and HFeNC could be candidates for their detection. We report geometrical parameters, vibrational frequencies, and rotational constants that could help with their experimental characterization.

  8. PREDICTION OF THE SPECTROSCOPIC PARAMETERS OF NEW IRON COMPOUNDS: HYDRIDE OF IRON CYANIDE/ISOCYANIDE, HFeCN/HFeNC

    International Nuclear Information System (INIS)

    Redondo, Pilar; Barrientos, Carmen; Largo, Antonio

    2016-01-01

    Iron is the most abundant transition metal in space. Its abundance is similar to that of magnesium, and until today only, FeO and FeCN have been detected. However, magnesium-bearing compounds such as MgCN, MgNC, and HMgNC are found in IRC+10216. It seems that the hydrides of iron cyanide/isocyanide could be good candidates to be present in space. In the present work we carried out a characterization of the different minima on the quintet and triplet [C, Fe, H, N] potential energy surfaces, employing several theoretical approaches. The most stable isomers are predicted to be hydride of iron cyanide HFeCN, and isocyanide HFeNC, in their 5 Δ states. Both isomers are found to be quasi-isoenergetics. The HFeNC isomer is predicted to lie about 0.5 kcal/mol below HFeCN. The barrier for the interconversion process is estimated to be around 6.0 kcal/mol, making this process unfeasible under low temperature conditions, such as those in the interstellar medium. Therefore, both HFeCN and HFeNC could be candidates for their detection. We report geometrical parameters, vibrational frequencies, and rotational constants that could help with their experimental characterization.

  9. Crystal structure of the coordination polymer [FeIII2{PtII(CN4}3

    Directory of Open Access Journals (Sweden)

    Maksym Seredyuk

    2015-01-01

    Full Text Available The title complex, poly[dodeca-μ-cyanido-diiron(IIItriplatinum(II], [FeIII2{PtII(CN4}3], has a three-dimensional polymeric structure. It is built-up from square-planar [PtII(CN4]2− anions (point group symmetry 2/m bridging cationic [FeIIIPtII(CN4]+∞ layers extending in the bc plane. The FeII atoms of the layers are located on inversion centres and exhibit an octahedral coordination sphere defined by six N atoms of cyanide ligands, while the PtII atoms are located on twofold rotation axes and are surrounded by four C atoms of the cyanide ligands in a square-planar coordination. The geometrical preferences of the two cations for octahedral and square-planar coordination, respectively, lead to a corrugated organisation of the layers. The distance between neighbouring [FeIIIPtII(CN4]+∞ layers corresponds to the length a/2 = 8.0070 (3 Å, and the separation between two neighbouring PtII atoms of the bridging [PtII(CN4]2− groups corresponds to the length of the c axis [7.5720 (2 Å]. The structure is porous with accessible voids of 390 Å3 per unit cell.

  10. Improvement of the Surface Hardness of Stainless Steel with the TitaniumCarbonitride Ti(CN) Thin Films

    International Nuclear Information System (INIS)

    Agus-Purwadi; Tri-Mardji Atmono; Widdi-Usada; Lely-Susita; Yunanto

    2000-01-01

    Fabrication of the T i (CN) thin films with methods of implantation and RFsputtering for improving the surfaces hardness of stainless steel (SS) hasbeen done. Some kinds of T i C thin films which made individually by varyingof RF sputtering power from 0 up to 160 watt are implanted by the nitrogenion beams on the doses and energy ion optimum of 6.107 x 10 17 ion/cm 2 and100 keV, also fabrication of T i (CN) thin films use RF sputtering method withT i target and reaction gases as argon, silene and nitrogen on the optimum ofsputtering parameter condition. The thin films yields are characterized byusing Microhardness Tester MX 170, obtained SS hardness which layered T i (CN)as 402.5 KHN from its initial of 215.54 KHN and 371.74 KHN (layered T i C), itmeans that the SS surface hardness improve 1.867 times cumulatively. From theX-Ray Diffraction (XRD) analysis yield showed that the microstructure ofT i (CN) films on the SS substrates are dominated by characteristic cubiccrystal structure with Miller plane orientation (111) on the scattering angleof 2 θ = 44 o . Morphology visualization of T i (CN) thin films crosssection on the SS substrate is realized by Spectroscopy Electron Microscope(SEM). (author)

  11. The 3 micron ice band

    International Nuclear Information System (INIS)

    Greenberg, J.M.; Bult, C.E.P.M. van de

    1984-01-01

    Ever since it was proposed that H 2 O could be a dominant constituent of interstellar grains, its detection, or lack thereof, has played a large role in theories of grains and their evolution. It now appears possible to provide a basic theoretical structure for the evolution of grains in molecular clouds based on current observational evidence and laboratory experiments on the ice band. Both band strengths and shapes can be reasonably predicted by grain models. (U.K.)

  12. Superdeformed bands in 130Ce

    International Nuclear Information System (INIS)

    Paul, E.S.; Semple, A.T.; Boston, A.J.; Joss, D.T.; Nolan, P.J.; Shepherd, S.L.

    1997-01-01

    Four superdeformed bands have been assigned to 130 Ce following a high-statistics γ-ray study using the EUROGAM II spectrometer. The strongest band exhibits two distinct backbends which, in one scenario, may be interpreted as crossings between high-j N = 6 neutron orbitals (νi 13/2 ) and low-j N = 4 orbitals (νd 3/2 ) in an unpaired system. (author)

  13. Dipole Bands in 196Hg

    International Nuclear Information System (INIS)

    Lawrie, J. J.; Lawrie, E. A.; Newman, R. T.; Sharpey-Schafer, J. F.; Smit, F. D.; Msezane, B.; Benatar, M.; Mabala, G. K.; Mutshena, K. P.; Federke, M.; Mullins, S. M.; Ncapayi, N. J.; Vymers, P.

    2011-01-01

    High spin states in 196 Hg have been populated in the 198 Pt(α,6n) reaction at 65 MeV and the level scheme has been extended. A new dipole band has been observed and a previously observed dipole has been confirmed. Excitation energies, spins and parities of these bands were determined from DCO ratio and linear polarization measurements. Possible quasiparticle excitations responsible for these structures are discussed.

  14. Guest Induced Strong Cooperative One- and Two-Step Spin Transitions in Highly Porous Iron(II) Hofmann-Type Metal-Organic Frameworks.

    Science.gov (United States)

    Piñeiro-López, Lucı A; Valverde-Muñoz, Francisco Javier; Seredyuk, Maksym; Muñoz, M Carmen; Haukka, Matti; Real, José Antonio

    2017-06-19

    The synthesis, crystal structure, magnetic, calorimetric, and Mössbauer studies of a series of new Hofmann-type spin crossover (SCO) metal-organic frameworks (MOFs) is reported. The new SCO-MOFs arise from self-assembly of Fe II , bis(4-pyridyl)butadiyne (bpb), and [Ag(CN) 2 ] - or [M II (CN) 4 ] 2- (M II = Ni, Pd). Interpenetration of four identical 3D networks with α-Po topology are obtained for {Fe(bpb)[Ag I (CN) 2 ] 2 } due to the length of the rod-like bismonodentate bpb and [Ag(CN) 2 ] - ligands. The four networks are tightly packed and organized in two subsets orthogonally interpenetrated, while the networks in each subset display parallel interpenetration. This nonporous material undergoes a very incomplete SCO, which is rationalized from its intricate structure. In contrast, the single network Hofmann-type MOFs {Fe(bpb)[M II (CN) 4 ]}·nGuest (M II = Ni, Pd) feature enhanced porosity and display complete one-step or two-step cooperative SCO behaviors when the pores are filled with two molecules of nitrobenzene or naphthalene that interact strongly with the pyridyl and cyano moieties of the bpb ligands via π-π stacking. The lack of these guest molecules favors stabilization of the high-spin state in the whole range of temperatures. However, application of hydrostatic pressure induces one- and two-step SCO.

  15. Effects of wildfires on ash Carbon, Nitrogen and C/N ratio in Mediterranean forests

    Science.gov (United States)

    Pereira, P.; Ubeda, X.; Martin, D. A.

    2009-04-01

    Carbon (C) and Nitrogen(N) are key nutrients in ecosystems health and the more affected by fire temperatures, because of their low temperatures of volatilization. After a wildfire, due higher temperatures reached, a great amount of C and N can be evacuated from the ecosystems and the percentage of C and N not vaporized is concentrated in ashes. Hence, the study of ash C and N is of major importance because will be linked with the capacity of ecosystem recuperation. The aim of this work is study the C, and C/N of three wildfires occurred in Mediterranean forests dominated by Quercus suber and Pinus pinea in Portugal. In the first wildfire, named "Quinta do Conde", we collected 30 samples, in the second, "Quinta da Areia", 32 samples and the third, "Casal do Sapo" 40 samples To estimate the consequences of wildfires in the parameters in study, we collected several samples of unburned litter near burned areas, composed by the same vegetation. The results showed that wildfires induced in % of Total Carbon (%TC) ashes content a non significantly reduction in Quinta do Conde plot (at a pPinus pinaster samples decreasing thereafter especially after the 400°C. In %TN we identified a rise in both species reducing abruptly at 450°C. C/N ratio decrease importantly after the 150°C. Theses results showed us that wildfires can have different effects C and N litter resources, depending on the severity and temperature reached. Crossing the results obtained in laboratory simulations with the samples collected in wildfires we will have an idea about the severity and temperature occurred in each wildfire. Overall, the lower severity were observed in Quinta do Conde plot and the higher in Casal do Sapo plot, being Quinta da Areia in a middle position. The C and N levels after a wildfire will determine the capacity of landscape recuperation and according the data obtained this will be higher in Quinta do Conde plot and lesser in Casal do Sapo plot. These hypothesis will be confirmed

  16. ON THE PROGENITOR OF THE TYPE II-PLATEAU SN 2008cn in NGC 4603

    International Nuclear Information System (INIS)

    Elias-Rosa, Nancy; Van Dyk, Schuyler D.; Li, Weidong; Filippenko, Alexei V.; Foley, Ryan J.; Smith, Nathan; Morrell, Nidia; Gonzalez, Sergio; Hamuy, Mario; Cuillandre, Jean-Charles

    2009-01-01

    A trend is emerging regarding the progenitor stars that give rise to the most common core-collapse supernovae (SNe), those of Type II-Plateau (II-P): they generally appear to be red supergiants with a limited range of initial masses, ∼8-16 M sun . Here, we consider another example, SN 2008cn, in the nearly face-on spiral galaxy NGC 4603. Even with limited photometric data, it appears that SN 2008cn is not a normal SN II-P, but is of the high-luminosity subclass. Through comparison of pre- and post-explosion images obtained with the Wide Field and Planetary Camera 2 on board the Hubble Space Telescope, we have isolated a supergiant star prior to explosion at nearly the same position as the SN. We provide evidence that this supergiant may well be the progenitor of the SN, although this identification is not entirely unambiguous. This is exacerbated by the distance to the host galaxy, 33.3 Mpc, making SN 2008cn the most distant SN II-P yet for which an attempt has been made to identify a progenitor star in pre-SN images. The progenitor candidate has a more yellow color ([V - I] 0 = 0.98 mag and T eff = 5200 ± 300 K) than generally would be expected and, if a single star, would require that it exploded during a 'blue loop' evolutionary phase, which is theoretically not expected to occur. Nonetheless, we estimate an initial mass of M ini = 15 ± 2 M sun for this star, which is within the expected mass range for SN II-P progenitors. The yellower color could also arise from the blend of two or more stars, such as a red supergiant and a brighter, blue supergiant. Such a red supergiant hidden in this blend could instead be the progenitor and would also have an initial mass within the expected progenitor mass range. Furthermore, the yellow supergiant could be in a massive, interacting binary system, analogous to the possible yellow supergiant progenitor of the high-luminosity SN II-P 2004et. Finally, if the yellow supergiant is not the progenitor, or is not a stellar

  17. Strong correlation and ferromagnetism in (Ga,Mn)As and (Ga,Mn)N

    International Nuclear Information System (INIS)

    Filippetti, A.; Spaldin, N.A.; Sanvito, S.

    2005-01-01

    The band energies of the ferromagnetic diluted magnetic semiconductors (Ga,Mn)As and (Ga,Mn)N are calculated using a self-interaction-free approach which describes covalent and strongly correlated electrons without adjustable parameters. Both materials are half-metallic, although the contribution of Mn-derived d states to the bands around the Fermi energy is very different in the two cases. In (Ga,Mn)As the bands are strongly p-d hybridized, with a dominance of As p states. In contrast in (Ga,Mn)N the Fermi energy lies within three flat bands of mainly d character that are occupied by two electrons. Thus the Mn ion in (Ga,Mn)N behaves as a deep trap acceptor, with the hole at 1.39 eV above the GaN valence band top, and is in excellent agreement with the experimental data

  18. Biogas Improvement by Adding Australian Zeolite During the Anaerobic Digestion of C:N Ratio Adjusted Swine Manure

    DEFF Research Database (Denmark)

    Wijesinghe, D. Thushari N.; Dassanayake, Kithsiri B.; Sommer, Sven G.

    2018-01-01

    Abstract: Maintenance of the ideal carbon: nitrogen (C:N) ratio with a minimum level of TAN is a key challenge for achieving maximum potential CH4 production through the anaerobic digestion process of agricultural waste such as swine manure. Biogas production can be enhanced by adding zeolite...... into the anaerobic digestion medium. However, the effects of zeolite addition to C:N ratio adjusted feedstock, on the digester performance is unknown. The objectives of this study were to investigate the effect of Australian zeolite on anaerobic digestion of swine manure with a C:N ratio adjusted to 30...... and to determine the optimal zeolite application rate to achieve the best performance. The Australian zeolite significantly enhanced CH4 production and reduced the lag phase of anaerobic digestion in batch production. The optimal addition rate of zeolite was appeared to be around 40 g/L. The better digester...

  19. A highly selective fluorescent chemosensor for CN- based on a novel bis(salamo)-type tetraoxime ligand

    Science.gov (United States)

    Wang, Fei; Gao, Lei; Zhao, Qing; Zhang, Yang; Dong, Wen-Kui; Ding, Yu-Jie

    2018-02-01

    The optical properties of a novel chemosensor for cyanide anions based on a symmetric bis(salamo)-type ligand (H3L) were investigated by UV-Vis and fluorescence spectroscopy in MeOH/H2O (1:1 v/v) solution. Sensor H3L can selectively sense CN- based on prominent color changes among other anions. The chemosensor exhibits an apparent fluorescence enhancement at 482 nm to CN- which because cyanide ions interact with Cdbnd N bonds. Combining the corrected Benesi-Hildebrand formula, the binding constant of the formed host-guest complex was calculated as 2.42 × 105 M- 1. Meanwhile, the detection limit of the sensor toward CN- was 8.91 × 10- 7 M. It is worth noting that the designed sensor can be used for rapid detection of cyanide anions in basic pH range, and has great practical value.

  20. Validity and extension of the SCS-CN method for computing infiltration and rainfall-excess rates

    Science.gov (United States)

    Mishra, Surendra Kumar; Singh, Vijay P.

    2004-12-01

    A criterion is developed for determining the validity of the Soil Conservation Service curve number (SCS-CN) method. According to this criterion, the existing SCS-CN method is found to be applicable when the potential maximum retention, S, is less than or equal to twice the total rainfall amount. The criterion is tested using published data of two watersheds. Separating the steady infiltration from capillary infiltration, the method is extended for predicting infiltration and rainfall-excess rates. The extended SCS-CN method is tested using 55 sets of laboratory infiltration data on soils varying from Plainfield sand to Yolo light clay, and the computed and observed infiltration and rainfall-excess rates are found to be in good agreement.

  1. Effective Biological Nitrogen Removal Treatment Processes for Domestic Wastewaters with Low C/N Ratios: A Review

    DEFF Research Database (Denmark)

    Sun, Sheng-Peng; Pellicer i Nàcher, Carles; Merkey, Brian

    2010-01-01

    with high efficiency and relative low costs. However, the removal of nitrogen from domestic wastewater with a low carbon/nitrogen (C/N) ratio can often be limited in municipal wastewater plants (WWTPs) because organic carbon is a limiting factor for denitrification. The present work reviews innovative....... They can effectively be used for nitrogen removal from low C/N domestic wastewater without external carbon addition. In addition, conventional and alternative carbon sources for enhanced biological nitrogen removal were also reviewed. We conclude that alternative carbon sources such as wine distillery...... at large scale for nitrogen removal from low C/N domestic wastewater, (2) further method logic are explored to introduce the Anammox pathway into domestic wastewater treatment, and (3) alternative carbon sources are explored and optimized for supporting the denitrification. With these efforts, cost...

  2. Rapid synthesis of graphitic carbon nitride powders by metathesis reaction between CaCN2 and C2Cl6

    International Nuclear Information System (INIS)

    Pang Linlin; Bi Jianqiang; Bai Yujun; Qi Yongxin; Zhu Huiling; Wang Chengguo; Wu Jiwei; Lu Chengwei

    2008-01-01

    Carbon nitride powders were rapidly synthesized at low temperature via the chemical metathesis reaction between CaCN 2 and C 2 Cl 6 . X-ray diffraction results confirm the formation of crystalline graphitic carbon nitride. Besides the dominant morphology of nanoparticles, flakes, nanorods, hollow and solid spheres can be observed by transmission electron microscopy. The absorption peaks of C-N, C=N and s-triazine rings, as well as the absence of C≡N peak in the infrared spectra, further verify the formation of graphite-like sp 2 -bonded structure with planar networks. Elemental analysis gives an atomic ratio of N/C around 0.3. X-ray photoelectron spectra exhibit the existence of chemical bonding between C and N

  3. Nursery Culture Performance of Litopenaeus vannamei with Probiotics Addition and Different C/N Ratio Under Laboratory Condition

    Directory of Open Access Journals (Sweden)

    WIDANARNI

    2010-09-01

    Full Text Available Application of bioflocs technology and probiotics has improved water quality and production of Pacific white shrimp (Litopenaeus vannamei culture. This experiment was to verify the effect of probiotic bacteria addition and different carbon:nitrogen (C:N ratio on water quality and performance of Pacific white shrimp nursery culture. Nursery culture was carried out for 25 days in an aquarium under laboratory condition with stock density of one Post-Larvae (PL (poslarval per liter (24 PL/aquarium of PL16 shrimp. Different C:N ratio resulted a significant difference on shrimp production performance. Treatment of 10 C:N ratio demonstrated the best shrimp growth (20.37 + 0.48% per day in weight and 6.05 + 0.41% per day in length, harvesting yield (1180 + 62 g/m3 and feed efficiency (121 + 6%. There was however no significant difference observed between treatments in water quality.

  4. Nursery Culture Performance of Litopenaeus vannamei with Probiotics Addition and Different C/N Ratio Under Laboratory Condition

    Directory of Open Access Journals (Sweden)

    WIDANARNI

    2010-09-01

    Full Text Available Application of bioflocs technology and probiotics has improved water quality and production of Pacific white shrimp (Litopenaeus vannamei culture. This experiment was to verify the effect of probiotic bacteria addition and different carbon:nitrogen (C:N ratio on water quality and performance of Pacific white shrimp nursery culture. Nursery culture was carried out for 25 days in an aquarium under laboratory condition with stock density of one Post-Larvae (PL (poslarval per liter (24 PL/aquarium of PL16 shrimp. Different C:N ratio resulted a significant difference on shrimp production performance. Treatment of 10 C:N ratio demonstrated the best shrimp growth (20.37 ± 0.48% per day in weight and 6.05 ± 0.41% per day in length, harvesting yield (1180 ± 62 g/m3 and feed efficiency (121 ± 6%. There was however no significant difference observed between treatments in water quality.

  5. Quantitative effects of composting state variables on C/N ratio through GA-aided multivariate analysis

    International Nuclear Information System (INIS)

    Sun Wei; Huang, Guo H.; Zeng Guangming; Qin Xiaosheng; Yu Hui

    2011-01-01

    It is widely known that variation of the C/N ratio is dependent on many state variables during composting processes. This study attempted to develop a genetic algorithm aided stepwise cluster analysis (GASCA) method to describe the nonlinear relationships between the selected state variables and the C/N ratio in food waste composting. The experimental data from six bench-scale composting reactors were used to demonstrate the applicability of GASCA. Within the GASCA framework, GA searched optimal sets of both specified state variables and SCA's internal parameters; SCA established statistical nonlinear relationships between state variables and the C/N ratio; to avoid unnecessary and time-consuming calculation, a proxy table was introduced to save around 70% computational efforts. The obtained GASCA cluster trees had smaller sizes and higher prediction accuracy than the conventional SCA trees. Based on the optimal GASCA tree, the effects of the GA-selected state variables on the C/N ratio were ranged in a descending order as: NH 4 + -N concentration > Moisture content > Ash Content > Mean Temperature > Mesophilic bacteria biomass. Such a rank implied that the variation of ammonium nitrogen concentration, the associated temperature and the moisture conditions, the total loss of both organic matters and available mineral constituents, and the mesophilic bacteria activity, were critical factors affecting the C/N ratio during the investigated food waste composting. This first application of GASCA to composting modelling indicated that more direct search algorithms could be coupled with SCA or other multivariate analysis methods to analyze complicated relationships during composting and many other environmental processes. - Research Highlights: → A genetic algorithm aided stepwise cluster analysis method in food waste composting. → Nonlinear relationships between the selected state variables and the C/N ratio. → Introduced proxy tables save around 70% computational

  6. Quantitative effects of composting state variables on C/N ratio through GA-aided multivariate analysis

    Energy Technology Data Exchange (ETDEWEB)

    Sun Wei [Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada); Huang, Guo H., E-mail: huangg@iseis.org [Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada); MOE Key Laboratory of Regional Energy Systems Optimization, Sino-Canada Energy and Environmental Research Academy, North China Electric Power University, Beijing, 102206 (China); Zeng Guangming [MOE Key Laboratory of Environmental Biology and Pollution Control, College of Environmental Science and Engineering, Hunan University, Changsha, Hunan, 410082 (China); Qin Xiaosheng [School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Yu Hui [Faculty of Engineering and Applied Science, University of Regina, Regina, Saskatchewan, S4S 0A2 (Canada)

    2011-03-01

    It is widely known that variation of the C/N ratio is dependent on many state variables during composting processes. This study attempted to develop a genetic algorithm aided stepwise cluster analysis (GASCA) method to describe the nonlinear relationships between the selected state variables and the C/N ratio in food waste composting. The experimental data from six bench-scale composting reactors were used to demonstrate the applicability of GASCA. Within the GASCA framework, GA searched optimal sets of both specified state variables and SCA's internal parameters; SCA established statistical nonlinear relationships between state variables and the C/N ratio; to avoid unnecessary and time-consuming calculation, a proxy table was introduced to save around 70% computational efforts. The obtained GASCA cluster trees had smaller sizes and higher prediction accuracy than the conventional SCA trees. Based on the optimal GASCA tree, the effects of the GA-selected state variables on the C/N ratio were ranged in a descending order as: NH{sub 4}{sup +}-N concentration > Moisture content > Ash Content > Mean Temperature > Mesophilic bacteria biomass. Such a rank implied that the variation of ammonium nitrogen concentration, the associated temperature and the moisture conditions, the total loss of both organic matters and available mineral constituents, and the mesophilic bacteria activity, were critical factors affecting the C/N ratio during the investigated food waste composting. This first application of GASCA to composting modelling indicated that more direct search algorithms could be coupled with SCA or other multivariate analysis methods to analyze complicated relationships during composting and many other environmental processes. - Research Highlights: {yields} A genetic algorithm aided stepwise cluster analysis method in food waste composting. {yields} Nonlinear relationships between the selected state variables and the C/N ratio. {yields} Introduced proxy tables

  7. Enhanced Photocatalytic Degradation of Methyl Orange Dye under the Daylight Irradiation over CN-TiO₂ Modified with OMS-2.

    Science.gov (United States)

    Hassan, Mohamed Elfatih; Chen, Jing; Liu, Guanglong; Zhu, Duanwei; Cai, Jianbo

    2014-12-12

    In this study, CN-TiO₂ was modified with cryptomelane octahedral molecular sieves (OMS-2) by the sol-gel method based on the self-assembly technique to enhance its photocatalytic activity under the daylight irradiation. The synthesized samples were characterized by X-ray diffraction (XRD), UV-vis spectroscopy, Fourier transform infrared spectroscopy (FT-IR) and porosimeter analysis. The results showed that the addition of OMS-2 in the sol lead to higher Brunauer-Emmett-Teller (BET) surface area, pore volume, porosity of particle after heat treatment and the specific surface area, porosity, crystallite size and pore size distribution could be controlled by adjusting the calcination temperature. Compared to the CN-TiO₂-400 sample, CN-TiO₂/OMS-2-400 exhibited greater red shift in absorption edge of samples in visible region due to the OMS-2 coated. The enhancement of photocatalytic activity of CN-TiO₂/OMS-2 composite photocatalyst was subsequently evaluated for the degradation of the methyl orange dye under the daylight irradiation in water. The results showed that the methyl orange dye degradation rate reach to 37.8% for the CN-TiO₂/OMS-2-400 sample under the daylight irradiation for 5 h, which was higher than that of reference sample. The enhancement in daylight photocatalytic activities of the CN-TiO₂/OMS samples could be attributed to the synergistic effects of OMS-2 coated, larger surface area and red shift in adsorption edge of the prepared sample.

  8. Synthesis and high temperature stability of amorphous Si(B)CN-MWCNT composite nanowires

    Science.gov (United States)

    Bhandavat, Romil; Singh, Gurpreet

    2012-02-01

    We demonstrate synthesis of a hybrid nanowire structure consisting of an amorphous polymer-derived silicon boron-carbonitride (Si-B-C-N) shell with a multiwalled carbon nanotube core. This was achieved through a novel process involving preparation of a boron-modified liquid polymeric precursor through a reaction of trimethyl borate and polyureasilazane under atmospheric conditions; followed by conversion of polymer to glass-ceramic on carbon nanotube surfaces through controlled heating. Chemical structure of the polymer was studied by liquid-NMR while evolution of various ceramic phases was studied by Raman spectroscopy, solid-NMR, Fourier transform infrared and X-ray photoelectron spectroscopy. Electron microscopy and X-ray diffraction confirms presence of amorphous Si(B)CN coating on individual nanotubes for all specimen processed below 1400 degree C. Thermogravimetric analysis, followed by TEM revealed high temperature stability of the carbon nanotube core in flowing air up to 1300 degree C.

  9. Thin films of amorphous nitrogenated carbon a-CN{sub x}: Electron transfer and surface reactivity

    Energy Technology Data Exchange (ETDEWEB)

    Tamiasso-Martinhon, P.; Cachet, H.; Debiemme-Chouvy, C.; Deslouis, C. [Universite Pierre et Marie Curie-Paris 6, Laboratoire Interfaces et Systemes Electrochimiques, CNRS, UPR15-LISE, 4 Place Jussieu, Paris F-75005 (France)

    2008-08-01

    The electrochemical behaviour of thin films of nitrogenated amorphous carbon a-CN{sub x} is similar to that of boron-doped diamond, with a wide potential window in aqueous media. They are elaborated by cathodic sputtering of a graphite target in an Ar-N{sub 2} active plasma for varying nitrogen contents, determined by XPS (0.06 {<=} x {<=} 0.39). Their electrochemical reactivity is sensitive to the surface state. The present study reports on the influence of electrochemical pre treatment on the electronic transfer rate of a fast redox system ferri-ferrocyanide, by focusing on the direction of the potential excursion. On the other hand, the role of both the pH and the potential on the interfacial capacitance in the presence of Na{sub 2}SO{sub 4} without redox species is documented. The results show up the sensitivity of the film surface to the electrochemical conditions. (author)

  10. A combined crossed molecular beams and theoretical study of the reaction CN + C2H4

    Science.gov (United States)

    Balucani, Nadia; Leonori, Francesca; Petrucci, Raffaele; Wang, Xingan; Casavecchia, Piergiorgio; Skouteris, Dimitrios; Albernaz, Alessandra F.; Gargano, Ricardo

    2015-03-01

    The CN + C2H4 reaction has been investigated experimentally, in crossed molecular beam (CMB) experiments at the collision energy of 33.4 kJ/mol, and theoretically, by electronic structure calculations of the relevant potential energy surface and Rice-Ramsperger-Kassel-Marcus (RRKM) estimates of the product branching ratio. Differently from previous CMB experiments at lower collision energies, but similarly to a high energy study, we have some indication that a second reaction channel is open at this collision energy, the characteristics of which are consistent with the channel leading to CH2CHNC + H. The RRKM estimates using M06L electronic structure calculations qualitatively support the experimental observation of C2H3NC formation at this and at the higher collision energy of 42.7 kJ/mol of previous experiments.

  11. Tear gasses CN, CR, and CS are potent activators of the human TRPA1 receptor

    International Nuclear Information System (INIS)

    Brone, Bert; Peeters, Pieter J.; Marrannes, Roger; Mercken, Marc; Nuydens, Ronny; Meert, Theo; Gijsen, Harrie J.M.

    2008-01-01

    The TRPA1 channel is activated by a number of pungent chemicals, such as allylisothiocyanate, present in mustard oil and thiosulfinates present in garlic. Most of the known activating compounds contain reactive, electrophilic chemical groups, reacting with cysteine residues in the active site of the TRPA1 channel. This covalent modification results in activation of the channel and has been shown to be reversible for several ligands. Commonly used tear gasses CN, CR and CS are also pungent chemicals, and in this study we show that they are extremely potent and selective activators of the human TRPA1 receptor. To our knowledge, these are the most potent TRPA1 agonists known to date. The identification of the molecular target for these tear gasses may open up possibilities to alleviate the effects of tear gasses via treatment with TRPA1 antagonists. In addition these results may contribute to the basic knowledge of the TRPA1 channel that is gaining importance as a pharmacological target

  12. Interaction between fullerene halves C_n (n ≤ 40) and single wall carbon nanotube

    International Nuclear Information System (INIS)

    Sharma, Amrish; Kaur, Sandeep; Mudahar, Isha

    2016-01-01

    We have investigated the structural and electronic properties of carbon nanotube with small fullerene halves C_n (n ≤ 40) which are covalently bonded to the side wall of an armchair single wall carbon nanotube (SWCNT) using first principle method based on density functional theory. The fullerene size results in weak bonding between fullerene halves and carbon nanotube (CNT). Further, it was found that the C-C bond distance that attaches the fullerene half and CNT is of the order of 1.60 Å. The calculated binding energies indicate the stability of the complexes formed. The HOMO-LUMO gaps and electron density of state plots points towards the metallicity of the complex formed. Our calculations on charge transfer reveal that very small amount of charge is transferred from CNT to fullerene halves.

  13. Strong coupling phase in QED

    International Nuclear Information System (INIS)

    Aoki, Ken-ichi

    1988-01-01

    Existence of a strong coupling phase in QED has been suggested in solutions of the Schwinger-Dyson equation and in Monte Carlo simulation of lattice QED. In this article we recapitulate the previous arguments, and formulate the problem in the modern framework of the renormalization theory, Wilsonian renormalization. This scheme of renormalization gives the best understanding of the basic structure of a field theory especially when it has a multi-phase structure. We resolve some misleading arguments in the previous literature. Then we set up a strategy to attack the strong phase, if any. We describe a trial; a coupled Schwinger-Dyson equation. Possible picture of the strong coupling phase QED is presented. (author)

  14. Catchment area-based evaluation of the AMC-dependent SCS-CN-based rainfall-runoff models

    Science.gov (United States)

    Mishra, S. K.; Jain, M. K.; Pandey, R. P.; Singh, V. P.

    2005-09-01

    Using a large set of rainfall-runoff data from 234 watersheds in the USA, a catchment area-based evaluation of the modified version of the Mishra and Singh (2002a) model was performed. The model is based on the Soil Conservation Service Curve Number (SCS-CN) methodology and incorporates the antecedent moisture in computation of direct surface runoff. Comparison with the existing SCS-CN method showed that the modified version performed better than did the existing one on the data of all seven area-based groups of watersheds ranging from 0.01 to 310.3 km2.

  15. Effect of nano-CeO 2 on microstructure properties of TiC/TiN+TiCN ...

    Indian Academy of Sciences (India)

    TiC/TiN+TiCN-reinforced composite coatings were fabricated on Ti–6Al–4V alloy by laser cladding, which improved surface performance of the substrate. ... X-ray diffraction results indicated that Al3Ti+TiC/TiN+nano-CeO2 laser-cladded coating consisted of Ti3Al, TiC, TiN, Ti2Al20Ce, TiC0.3N0.7, Ce(CN)3 and CeO2, this ...

  16. In situ measurements of HCN and CH3CN over the Pacific Ocean: Sources, sinks, and budgets

    Science.gov (United States)

    Singh, H. B.; Salas, L.; Herlth, D.; Kolyer, R.; Czech, E.; Viezee, W.; Li, Q.; Jacob, D. J.; Blake, D.; Sachse, G.; Harward, C. N.; Fuelberg, H.; Kiley, C. M.; Zhao, Y.; Kondo, Y.

    2003-10-01

    We report the first in situ measurements of hydrogen cyanide (HCN) and methyl cyanide (CH3CN, acetonitrile) from the Pacific troposphere (0-12 km) obtained during the NASA Transport and Chemical Evolution over the Pacific (TRACE-P) airborne mission (February-April 2001). Mean HCN and CH3CN mixing ratios of 243 ± 118 (median 218) ppt and 149 ± 56 (median 138) ppt, respectively, were measured. These in situ observations correspond to a mean tropospheric HCN column of 4.2 × 1015 molecules cm-2 and a CH3CN column of 2.5 × 1015 molecules cm-2. This is in good agreement with the 0-12 km HCN column of 4.4 (±0.6) × 1015 molecules cm-2 derived from infrared solar spectroscopic observations over Japan. Mixing ratios of HCN and CH3CN were greatly enhanced in pollution outflow from Asia and were well correlated with each other as well as with known tracers of biomass combustion (e.g., CH3Cl, CO). Volumetric enhancement (or emission) ratios (ERs) relative to CO in free tropospheric plumes, likely originating from fires, were 0.34% for HCN and 0.17% for CH3CN. ERs with respect to CH3Cl and CO in selected biomass burning (BB) plumes in the free troposphere and in boundary layer pollution episodes are used to estimate a global BB source of 0.8 ± 0.4 Tg (N) yr-1 for HCN and 0.4 ± 0.1 Tg (N) yr-1 for CH3CN. In comparison, emissions from industry and fossil fuel combustion are quite small (atmospheric residence time of 5.0 months for HCN and 6.6 months for CH3CN is calculated. A global budget analysis shows that the sources and sinks of HCN and CH3CN are roughly in balance but large uncertainties remain in part due to a lack of observational data from the atmosphere and the oceans. Pathways leading to the oceanic (and soil) degradation of these cyanides are poorly known but are expected to be biological in nature.

  17. Growth feature of ionic nitrogen doped CN_x bilayer films with Ti and TiN interlayer by pulse cathode arc discharge

    International Nuclear Information System (INIS)

    Zhou, Bing; Liu, Zhubo; Piliptsou, D.G.; Rogachev, A.V.; Yu, Shengwang; Wu, Yanxia; Tang, Bin; Rudenkov, A.S.

    2016-01-01

    Graphical abstract: - Highlights: • Ti/ and TiN/CN_x (N"+) bilayers are prepared at various frequencies by pulse cathode arc. • Ti interlayer facilitates the introduction of N atoms into the CN_x (N"+) films. • The most N-sp"2C bonds (mainly graphite-like N) present in the TiN/CN_x (N"+, 3 Hz) film. • Ti/CN_x (N"+, 3 Hz) bilayer possesses small size and disordering of Csp"2 clusters. • The higher hardness and the lower stress presents in the TiN/CN_x (N"+, 10 Hz) bilayer. - Abstract: Using nano-scaled Ti and TiN as interlayer, ionic nitrogen doped carbon (CN_x (N"+)) bilayer films were prepared at various pulse frequencies by cathode arc technique. Elemental distribution at the interface, bonding compositions, microstructure, and mechanical properties of CN_x (N"+) bilayer films were investigated in dependence of interlayer and pulse frequency by Auger electron spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, nanoindentation, and surface profilometer. The results showed that the diffusion extent of C atoms at the interface of CN_x (N"+) bilayers is higher than for the α-C and CN_x (N_2) bilayers with the same interlayer. Nitrogen atoms could diffuse throughout the pre-deposited Ti and TiN layers into the Si substrate for all CN_x (N"+) bilayers. Ti interlayer facilitates the introduction of N atoms into the CN_x (N"+) films and exhibits a certain catalytic effect on the coordination of N atoms with sp"2- and sp"3-C binding. More nitrogenated and intense CN bonding configurations (mainly graphite-like N) form in the TiN/CN_x (N"+) bilayer. Ti/CN_x (N"+) bilayer prepared at low frequency possesses small size and disordering of Csp"2 clusters but TiN interlayer weakens the formation of Csp"2 bonding and increases the disordering of Csp"2 clusters in the films. The residual stress in the bilayer is lower than for CN_x (N"+) monolayer. The higher hardness and the lower residual stress are present in the TiN/CN_x (N"+, 10 Hz) bilayer.

  18. Density functional study of electronic, magnetic and hyperfine properties of [M(CN)5 NO]2- (M=Fe, Ru) and reduction products

    International Nuclear Information System (INIS)

    Gomez, J.A.; Guenzburger, Diana

    1999-06-01

    The Discrete Variational method (DVM) in density functional theory was employed to investigate the electronic structure of the complexes [Fe(CN) 5 NO] 2- (Nitroprusside), [Fe(CN) 5 NO] 3- , [Fe(CN) 4 NO] 2- , [Ru(CN) 5 NO] 2- and [Ru(CN) 5 NO] 3- . Total energy calculations revealed that in pentacyano nitrosyl ferrate (I) and pentacyano nitrosyl ruthenate (I), which are paramagnetic ions containing one unpaired electron, the M-N-O angle is bent, having values of 152.5 deg and 144 deg, respectively. From self-consistent spin-polarized calculations, the distribution of unpaired electron in the paramagnetic complexes [Fe(CN) 5 NO] 3, [Fe(CN) 4 NO] 2- and [Ru(CN) 5 NO] 3- was obtained as well as spin-density maps. A long-standing controversy regarding the configuration of [Fe(CN) 5 NO] 3- was elucidated, and it was found that the unpaired electron in this complex is in an orbital primarily localized on π * (NO). Moessbauer quadrupole splittings on Fe and Ru were derived from calculations of the electric-field gradients. Magnetic hyperfine coupling constants on No of the NO ligand were also obtained for the paramagnetic complexes. (author)

  19. Post-transition state dynamics and product energy partitioning following thermal excitation of the F⋯HCH2CN transition state: Disagreement with experiment.

    Science.gov (United States)

    Pratihar, Subha; Ma, Xinyou; Xie, Jing; Scott, Rebecca; Gao, Eric; Ruscic, Branko; Aquino, Adelia J A; Setser, Donald W; Hase, William L

    2017-10-14

    Born-Oppenheimer direct dynamics simulations were performed to study atomistic details of the F + CH 3 CN → HF + CH 2 CN H-atom abstraction reaction. The simulation trajectories were calculated with a combined M06-2X/MP2 algorithm utilizing the 6-311++G** basis set. The experiments were performed at 300 K, and assuming the accuracy of transition state theory (TST), the trajectories were initiated at the F⋯HCH 2 CN abstraction TS with a 300 K Boltzmann distribution of energy and directed towards products. Recrossing of the TS was negligible, confirming the accuracy of TST. HF formation was rapid, occurring within 0.014 ps of the trajectory initiation. The intrinsic reaction coordinate (IRC) for reaction involves rotation of HF about CH 2 CN and then trapping in the CH 2 CN⋯HF post-reaction potential energy well of ∼10 kcal/mol with respect to the HF + CH 2 CN products. In contrast to this IRC, five different trajectory types were observed: the majority proceeded by direct H-atom transfer and only 11% approximately following the IRC. The HF vibrational and rotational quantum numbers, n and J, were calculated when HF was initially formed and they increase as potential energy is released in forming the HF + CH 2 CN products. The population of the HF product vibrational states is only in qualitative agreement with experiment, with the simulations showing depressed and enhanced populations of the n = 1 and 2 states as compared to experiment. Simulations with an anharmonic zero-point energy constraint gave product distributions for relative translation, HF rotation, HF vibration, CH 2 CN rotation, and CH 2 CN vibration as 5%, 11%, 60%, 7%, and 16%, respectively. In contrast, the experimental energy partitioning percentages to HF rotation and vibration are 6% and 41%. Comparisons are made between the current simulation and those for other F + H-atom abstraction reactions. The simulation product energy partitioning and HF vibrational population for F + CH 3 CN

  20. Improved Algorithm of SCS-CN Model Parameters in Typical Inland River Basin in Central Asia

    Science.gov (United States)

    Wang, Jin J.; Ding, Jian L.; Zhang, Zhe; Chen, Wen Q.

    2017-02-01

    Rainfall-runoff relationship is the most important factor for hydrological structures, social and economic development on the background of global warmer, especially in arid regions. The aim of this paper is find the suitable method to simulate the runoff in arid area. The Soil Conservation Service Curve Number (SCS-CN) is the most popular and widely applied model for direct runoff estimation. In this paper, we will focus on Wen-quan Basin in source regions of Boertala River. It is a typical valley of inland in Central Asia. First time to use the 16m resolution remote sensing image about high-definition earth observation satellite “Gaofen-1” to provide a high degree accuracy data for land use classification determine the curve number. Use surface temperature/vegetation index (TS/VI) construct 2D scatter plot combine with the soil moisture absorption balance principle calculate the moisture-holding capacity of soil. Using original and parameter algorithm improved SCS-CN model respectively to simulation the runoff. The simulation results show that the improved model is better than original model. Both of them in calibration and validation periods Nash-Sutcliffe efficiency were 0.79, 0.71 and 0.66,038. And relative error were3%, 12% and 17%, 27%. It shows that the simulation accuracy should be further improved and using remote sensing information technology to improve the basic geographic data for the hydrological model has the following advantages: 1) Remote sensing data having a planar characteristic, comprehensive and representative. 2) To get around the bottleneck about lack of data, provide reference to simulation the runoff in similar basin conditions and data-lacking regions.

  1. Single-Band and Dual-Band Infrared Detectors

    Science.gov (United States)

    Ting, David Z. (Inventor); Gunapala, Sarath D. (Inventor); Soibel, Alexander (Inventor); Nguyen, Jean (Inventor); Khoshakhlagh, Arezou (Inventor)

    2017-01-01

    Bias-switchable dual-band infrared detectors and methods of manufacturing such detectors are provided. The infrared detectors are based on a back-to-back heterojunction diode design, where the detector structure consists of, sequentially, a top contact layer, a unipolar hole barrier layer, an absorber layer, a unipolar electron barrier, a second absorber, a second unipolar hole barrier, and a bottom contact layer. In addition, by substantially reducing the width of one of the absorber layers, a single-band infrared detector can also be formed.

  2. Adhesives for fixed orthodontic bands.

    Science.gov (United States)

    Millett, Declan T; Glenny, Anne-Marie; Mattick, Rye Cr; Hickman, Joy; Mandall, Nicky A

    2016-10-25

    Orthodontic treatment involves using fixed or removable appliances (dental braces) to correct the positions of teeth. It has been shown that the quality of treatment result obtained with fixed appliances is much better than with removable appliances. Fixed appliances are, therefore, favoured by most orthodontists for treatment. The success of a fixed orthodontic appliance depends on the metal attachments (brackets and bands) being attached securely to the teeth so that they do not become loose during treatment. Brackets are usually attached to the front and side teeth, whereas bands (metal rings that go round the teeth) are more commonly used on the back teeth (molars). A number of adhesives are available to attach bands to teeth and it is important to understand which group of adhesives bond most reliably, as well as reducing or preventing dental decay during the treatment period. To evaluate the effectiveness of the adhesives used to attach bands to teeth during fixed appliance treatment, in terms of:(1) how often the bands come off during treatment; and(2) whether they protect the banded teeth against decay during fixed appliance treatment. The following electronic databases were searched: Cochrane Oral Health's Trials Register (searched 2 June 2016), Cochrane Central Register of Controlled Trials (CENTRAL; 2016, Issue 5) in the Cochrane Library (searched 2 June 2016), MEDLINE Ovid (1946 to 2 June 2016) and EMBASE Ovid (1980 to 2 June 2016). We searched ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform for ongoing trials. No restrictions were placed on the language or date of publication when searching the electronic databases. Randomised and controlled clinical trials (RCTs and CCTs) (including split-mouth studies) of adhesives used to attach orthodontic bands to molar teeth were selected. Patients with full arch fixed orthodontic appliance(s) who had bands attached to molars were included. All review authors

  3. Strong interactions at high energy

    International Nuclear Information System (INIS)

    Anselmino, M.

    1995-01-01

    Spin effects in strong interaction high energy processes are subtle phenomena which involve both short and long distance physics and test perturbative and non perturbative aspects of QCD. Moreover, depending on quantities like interferences between different amplitudes and relative phases, spin observables always test a theory at a fundamental quantum mechanical level; it is then no surprise that spin data are often difficult to accommodate within the existing models. A report is made on the main issues and contributions discussed in the parallel Session on the open-quote open-quote Strong interactions at high energy close-quote close-quote in this Conference. copyright 1995 American Institute of Physics

  4. Strong-field dissociation dynamics

    International Nuclear Information System (INIS)

    DiMauro, L.F.; Yang, Baorui.

    1993-01-01

    The strong-field dissociation behavior of diatomic molecules is examined under two distinctive physical scenarios. In the first scenario, the dissociation of the isolated hydrogen and deuterium molecular ions is discussed. The dynamics of above-threshold dissociation (ATD) are investigated over a wide range of green and infrared intensities and compared to a dressed-state model. The second situation arises when strong-field neutral dissociation is followed by ionization of the atomic fragments. The study results in a direct measure of the atomic fragment's ac-Stark shift by observing the intensity-dependent shifts in the electron or nuclear fragment kinetic energy. 8 figs., 14 refs

  5. Dilatant shear band formation and diagenesis in calcareous, arkosic sandstones, Vienna Basin (Austria)

    Science.gov (United States)

    Lommatzsch, Marco; Exner, Ulrike; Gier, Susanne; Grasemann, Bernhard

    2015-01-01

    The present study examines deformation bands in calcareous arkosic sands. The investigated units can be considered as an equivalent to the Matzen field in the Vienna Basin (Austria), which is one of the most productive oil reservoirs in central Europe. The outcrop exposes carbonate-free and carbonatic sediments of Badenian age separated by a normal fault. Carbonatic sediments in the hanging wall of the normal fault develop dilation bands with minor shear displacements (< 2 mm), whereas carbonate-free sediments in the footwall develop cataclastic shear bands with up to 70 cm displacement. The cataclastic shear bands show a permeability reduction up to 3 orders of magnitude and strong baffling effects in the vadose zone. Carbonatic dilation bands show a permeability reduction of 1-2 orders of magnitude and no baffling structures. We distinguished two types of deformation bands in the carbonatic units, which differ in deformation mechanisms, distribution and composition. Full-cemented bands form as dilation bands with an intense syn-kinematic calcite cementation, whereas the younger loose-cemented bands are dilatant shear bands cemented by patchy calcite and clay minerals. All analyzed bands are characterized by a porosity and permeability reduction caused by grain fracturing and cementation. The changed petrophysical properties and especially the porosity evolution are closely related to diagenetic processes driven by varying pore fluids in different diagenetic environments. The deformation band evolution and sealing capacity is controlled by the initial host rock composition. PMID:26300577

  6. Band structure and Fermi surface of UPd2Al3 studied by angle-resolved photoemission spectroscopy

    International Nuclear Information System (INIS)

    Fujimori, Shin-ichi; Saitoh, Yuji; Okane, Tetsuo; Yamagami, Hiroshi; Fujimori, Atsushi; Haga, Yoshinori; Yamamoto, Etsuji; Onuki, Yoshichika

    2007-01-01

    We have observed the band structure and Fermi surfaces of the heavy Fermion superconductor UPd 2 Al 3 by angle-resolved photoemission experiments in the soft X-ray region. We observed renormalized quasi-particle bands in the vicinity of the Fermi level and strongly dispersive bands on the higher binding energy side. Our observation suggests that the structure previously assigned to contributions from localized states in the U 5f spectrum has strong energy dispersions

  7. Mixed State of a Dirty Two-Band Superconductor: Application to MgB2

    NARCIS (Netherlands)

    Koshelev, A.E.; Golubov, Alexandre Avraamovitch

    2003-01-01

    We investigate the vortex state in a two-band superconductor with strong intraband and weak interband electronic scattering rates. Coupled Usadel equations are solved numerically, and the distributions of the pair potentials and local densities of states are calculated for two bands at different

  8. Left temporal alpha band activity increases during working memory retention of pitches

    NARCIS (Netherlands)

    Van Dijk, H.; Nieuwenhuis, I.L.C.; Jensen, O.

    2010-01-01

    The functional role and regional specificity of similar to 10 Hz alpha band activity remains of debate. Alpha band activity is strongly modulated in visual working memory tasks and it has been proposed to subserve resource allocation by disengaging task-irrelevant regions. It remains unknown if

  9. Electron and hole states in quantum dot quantum wells within a spherical eight-band model

    NARCIS (Netherlands)

    Pokatilov, E.P.; Fonoberov, V.A.; Fomin, V.; Devreese, J.T.

    2001-01-01

    In order to study heterostructures composed both of materials with strongly different parameters and of materials with narrow band gaps, we have developed an approach [E. P. Pokatilov [etal], Phys. Rev. B 64, 245328 (2001), (preceding paper)], which combines the spherical eight-band effective-mass

  10. Gold nano-particle formation from crystalline AuCN: Comparison of thermal, plasma- and ion-beam activated decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Beck, Mihály T.; Bertóti, Imre, E-mail: bertoti.imre@ttk.mta.hu; Mohai, Miklós; Németh, Péter; Jakab, Emma; Szabó, László; Szépvölgyi, János

    2017-02-15

    In this work, in addition to the conventional thermal process, two non-conventional ways, the plasma and ion beam activations are described for preparing gold nanoparticles from microcrystalline AuCN precursor. The phase formation at plasma and ion beam treatments was compared with that at thermal treatments and the products and transformations were characterized by thermogravimetry-mass-spectrometry (TG-MS), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM). TG-MS measurements in Ar atmosphere revealed that AuCN decomposition starts at 400 °C and completes at ≈700 °C with evolution of gaseous (CN){sub 2}. XPS and TEM show that in heat treatment at 450 °C for 1 h in Ar, loss of nitrogen and carbon occurs and small, 5–30 nm gold particles forms. Heating at 450 °C for 10 h in sealed ampoule, much larger, 60–200 nm size and well faceted Au particles develop together with a fibrous (CN){sub n} polymer phase, and the Au crystallites are covered by a 3–5 nm thick polymer shell. Low pressure Ar plasma treatment at 300 eV energy results in 4–20 nm size Au particles and removes most of the nitrogen and part of carbon. During Ar{sup +} ion bombardment with 2500 eV energy, 5–30 nm size Au crystallites form already in 10 min, with preferential loss of nitrogen and with increased amount of carbon residue. The results suggest that plasma and ion beam activation, acting similarly to thermal treatment, may be used to prepare Au nanoparticles from AuCN on selected surface areas either by depositing AuCN precursors on selected regions or by focusing the applied ionized radiation. Thus they may offer alternative ways for preparing tailor-made catalysts, electronic devices and sensors for different applications. - Graphical abstract: Proposed scheme of the decomposition mechanism of AuCN samples: heat treatment in Ar flow (a) and in sealed ampoule (b); Ar{sup +} ion treatment at 300 eV (c) and at 2500 eV (d). Cross section sketches

  11. Designing Phononic Crystals with Wide and Robust Band Gaps

    Science.gov (United States)

    Jia, Zian; Chen, Yanyu; Yang, Haoxiang; Wang, Lifeng

    2018-04-01

    Phononic crystals (PnCs) engineered to manipulate and control the propagation of mechanical waves have enabled the design of a range of novel devices, such as waveguides, frequency modulators, and acoustic cloaks, for which wide and robust phononic band gaps are highly preferable. While numerous PnCs have been designed in recent decades, to the best of our knowledge, PnCs that possess simultaneous wide and robust band gaps (to randomness and deformations) have not yet been reported. Here, we demonstrate that by combining the band-gap formation mechanisms of Bragg scattering and local resonances (the latter one is dominating), PnCs with wide and robust phononic band gaps can be established. The robustness of the phononic band gaps are then discussed from two aspects: robustness to geometric randomness (manufacture defects) and robustness to deformations (mechanical stimuli). Analytical formulations further predict the optimal design parameters, and an uncertainty analysis quantifies the randomness effect of each designing parameter. Moreover, we show that the deformation robustness originates from a local resonance-dominant mechanism together with the suppression of structural instability. Importantly, the proposed PnCs require only a small number of layers of elements (three unit cells) to obtain broad, robust, and strong attenuation bands, which offer great potential in designing flexible and deformable phononic devices.

  12. Designing Phononic Crystals with Wide and Robust Band Gaps

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yanyu [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jia, Zian [State University of New York at Stony Brook; Yang, Haoxiang [State University of New York at Stony Brook; Wang, Lifeng [State University of New York at Stony Brook

    2018-04-16

    Phononic crystals (PnCs) engineered to manipulate and control the propagation of mechanical waves have enabled the design of a range of novel devices, such as waveguides, frequency modulators, and acoustic cloaks, for which wide and robust phononic band gaps are highly preferable. While numerous PnCs have been designed in recent decades, to the best of our knowledge, PnCs that possess simultaneous wide and robust band gaps (to randomness and deformations) have not yet been reported. Here, we demonstrate that by combining the band-gap formation mechanisms of Bragg scattering and local resonances (the latter one is dominating), PnCs with wide and robust phononic band gaps can be established. The robustness of the phononic band gaps are then discussed from two aspects: robustness to geometric randomness (manufacture defects) and robustness to deformations (mechanical stimuli). Analytical formulations further predict the optimal design parameters, and an uncertainty analysis quantifies the randomness effect of each designing parameter. Moreover, we show that the deformation robustness originates from a local resonance-dominant mechanism together with the suppression of structural instability. Importantly, the proposed PnCs require only a small number of layers of elements (three unit cells) to obtain broad, robust, and strong attenuation bands, which offer great potential in designing flexible and deformable phononic devices.

  13. New edge-centered photonic square lattices with flat bands

    Science.gov (United States)

    Zhang, Da; Zhang, Yiqi; Zhong, Hua; Li, Changbiao; Zhang, Zhaoyang; Zhang, Yanpeng; Belić, Milivoj R.

    2017-07-01

    We report a new class of edge-centered photonic square lattices with multiple flat bands, and consider in detail two examples: the Lieb-5 and Lieb-7 lattices. In these lattices, there are 5 and 7 sites in the unit cell and in general, the number is restricted to odd integers. The number of flat bands m in the new Lieb lattices is related to the number of sites N in the unit cell by a simple formula m =(N - 1) / 2. The flat bands reported here are independent of the pseudomagnetic field. The properties of lattices with even and odd number of flat bands are different. We consider the localization of light in such Lieb lattices. If the input beam excites the flat-band mode, it will not diffract during propagation, owing to the strong mode localization. In the Lieb-7 lattice, the beam will also oscillate during propagation and still not diffract. The period of oscillation is determined by the energy difference between the two flat bands. This study provides a new platform for investigating light trapping, photonic topological insulators, and pseudospin-mediated vortex generation.

  14. Band Gap Modulated by Electronic Superlattice in Blue Phosphorene.

    Science.gov (United States)

    Zhuang, Jincheng; Liu, Chen; Gao, Qian; Liu, Yani; Feng, Haifeng; Xu, Xun; Wang, Jiaou; Zhao, Jijun; Dou, Shi Xue; Hu, Zhenpeng; Du, Yi

    2018-05-22

    Exploring stable two-dimensional materials with appropriate band gaps and high carrier mobility is highly desirable due to the potential applications in optoelectronic devices. Here, the electronic structures of phosphorene on a Au(111) substrate are investigated by scanning tunneling spectroscopy, angle-resolved photoemission spectroscopy (ARPES), and density functional theory (DFT) calculations. The substrate-induced phosphorene superstructure gives a superlattice potential, leading to a strong band folding effect of the sp band of Au(111) on the band structure. The band gap could be clearly identified in the ARPES results after examining the folded sp band. The value of the energy gap (∼1.1 eV) and the high charge carrier mobility comparable to that of black phosphorus, which is engineered by the tensile strain, are revealed by the combination of ARPES results and DFT calculations. Furthermore, the phosphorene layer on the Au(111) surface displays high surface inertness, leading to the absence of multilayer phosphorene. All these results suggest that the phosphorene on Au(111) could be a promising candidate, not only for fundamental research but also for nanoelectronic and optoelectronic applications.

  15. Strong Decomposition of Random Variables

    DEFF Research Database (Denmark)

    Hoffmann-Jørgensen, Jørgen; Kagan, Abram M.; Pitt, Loren D.

    2007-01-01

    A random variable X is stongly decomposable if X=Y+Z where Y=Φ(X) and Z=X-Φ(X) are independent non-degenerated random variables (called the components). It is shown that at least one of the components is singular, and we derive a necessary and sufficient condition for strong decomposability...... of a discrete random variable....

  16. Strong coupling electroweak symmetry breaking

    International Nuclear Information System (INIS)

    Barklow, T.L.; Burdman, G.; Chivukula, R.S.

    1997-04-01

    The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models

  17. Strong coupling electroweak symmetry breaking

    Energy Technology Data Exchange (ETDEWEB)

    Barklow, T.L. [Stanford Linear Accelerator Center, Menlo Park, CA (United States); Burdman, G. [Univ. of Wisconsin, Madison, WI (United States). Dept. of Physics; Chivukula, R.S. [Boston Univ., MA (United States). Dept. of Physics

    1997-04-01

    The authors review models of electroweak symmetry breaking due to new strong interactions at the TeV energy scale and discuss the prospects for their experimental tests. They emphasize the direct observation of the new interactions through high-energy scattering of vector bosons. They also discuss indirect probes of the new interactions and exotic particles predicted by specific theoretical models.

  18. The colours of strong interaction

    International Nuclear Information System (INIS)

    1995-01-01

    The aim of this session is to draw a consistent framework about the different ways to consider strong interaction. A large part is dedicated to theoretical work and the latest experimental results obtained at the first electron collider HERA are discussed. (A.C.)

  19. Strong cosmic censorship and the strong curvature singularities

    International Nuclear Information System (INIS)

    Krolak, A.

    1987-01-01

    Conditions are given under which any asymptotically simple and empty space-time that has a partial Cauchy surface with an asymptotically simple past is globally hyperbolic. It is shown that this result suggests that the Cauchy horizons of the type occurring in Reissner--Nordstroem and Kerr space-times are unstable. This in turn gives support for the validity of the strong cosmic censorship hypothesis

  20. Point-Defect Nature of the Ultraviolet Absorption Band in AlN

    Science.gov (United States)

    Alden, D.; Harris, J. S.; Bryan, Z.; Baker, J. N.; Reddy, P.; Mita, S.; Callsen, G.; Hoffmann, A.; Irving, D. L.; Collazo, R.; Sitar, Z.

    2018-05-01

    We present an approach where point defects and defect complexes are identified using power-dependent photoluminescence excitation spectroscopy, impurity data from SIMS, and density-functional-theory (DFT)-based calculations accounting for the total charge balance in the crystal. Employing the capabilities of such an experimental computational approach, in this work, the ultraviolet-C absorption band at 4.7 eV, as well as the 2.7- and 3.9-eV luminescence bands in AlN single crystals grown via physical vapor transport (PVT) are studied in detail. Photoluminescence excitation spectroscopy measurements demonstrate the relationship between the defect luminescent bands centered at 3.9 and 2.7 eV to the commonly observed absorption band centered at 4.7 eV. Accordingly, the thermodynamic transition energy for the absorption band at 4.7 eV and the luminescence band at 3.9 eV is estimated at 4.2 eV, in agreement with the thermodynamic transition energy for the CN- point defect. Finally, the 2.7-eV PL band is the result of a donor-acceptor pair transition between the VN and CN point defects since nitrogen vacancies are predicted to be present in the crystal in concentrations similar to carbon-employing charge-balance-constrained DFT calculations. Power-dependent photoluminescence measurements reveal the presence of the deep donor state with a thermodynamic transition energy of 5.0 eV, which we hypothesize to be nitrogen vacancies in agreement with predictions based on theory. The charge state, concentration, and type of impurities in the crystal are calculated considering a fixed amount of impurities and using a DFT-based defect solver, which considers their respective formation energies and the total charge balance in the crystal. The presented results show that nitrogen vacancies are the most likely candidate for the deep donor state involved in the donor-acceptor pair transition with peak emission at 2.7 eV for the conditions relevant to PVT growth.

  1. Crosstalk effect and its mitigation in Aqua MODIS middle wave infrared bands

    Science.gov (United States)

    Sun, Junqiang; Madhavan, Sriharsha; Wang, Menghua

    2017-09-01

    The MODerate-resolution Imaging Spectroradiometer (MODIS) is one of the primary instruments in the National Aeronautics and Space Administration (NASA) Earth Observing System (EOS). The first MODIS instrument was launched in December 1999 on-board the Terra spacecraft. A follow on MODIS was launched on an afternoon orbit in 2002 and is aboard the Aqua spacecraft. Both MODIS instruments are very akin, has 36 bands, among which bands 20 to 25 are Middle Wave Infrared (MWIR) bands covering a wavelength range from approximately 3.750 μm to 4.515 μm. It was found that there was severe contamination in these bands early in mission but the effect has not been characterized and mitigated at the time. The crosstalk effect induces strong striping in the Earth View (EV) images and causes significant retrieval errors in the EV Brightness Temperature (BT) in these bands. An algorithm using a linear approximation derived from on-orbit lunar observations has been developed to correct the crosstalk effect and successfully applied to mitigate the effect in both Terra and Aqua MODIS Long Wave Infrared (LWIR) Photovoltaic (PV) bands. In this paper, the crosstalk effect in the Aqua MWIR bands is investigated and characterized by deriving the crosstalk coefficients using the scheduled Aqua MODIS lunar observations for the MWIR bands. It is shown that there are strong crosstalk contaminations among the five MWIR bands and they also have significant crosstalk contaminations from Short Wave Infrared (SWIR) bands. The crosstalk correction algorithm previously developed is applied to correct the crosstalk effect in these bands. It is demonstrated that the crosstalk correction successfully reduces the striping in the EV images and improves the accuracy of the EV BT in the five bands as was done similarly for LWIR PV bands. The crosstalk correction algorithm should thus be applied to improve both the image quality and radiometric accuracy of the Aqua MODIS MWIR bands Level 1B (L1B) products.

  2. Collective motions and band structures in A = 60 to 80, even--even nuclei

    International Nuclear Information System (INIS)

    Hamilton, J.H.; Robinson, R.L.; Ramayya, A.V.

    1978-01-01

    Evidence for and the theoretical understanding of the richness of the collective band structures as illustrated by at least seven bands seen in levels of 68 Ge, 74 Se are reviewed. The experimental data on even-even nuclei in the A = 60 to 80 region have now revealed a wide variety of collective bands with different structures. The even parity yrast cascades alone are seen to involve multiple collective structures. In addition to the ground-state bands, strong evidence is presented for both neutron and proton rotation-aligned bands built on the same orbital, (g 9 / 2 ) 2 , in one nucleus. Several other nuclei also show the crossing of RAL bands around the 8 + level in this region. Evidence continues to be strong experimentally and supported theoretically that there is some type of shape transition and shape coexistence occurring now both in the Ge and Se isotopes around N = 40. Negative parity bands with odd and even spins with very collective nature are seen in several nuclei to high spin. These bands seem best understood in the RAL model. Very collective bands with ΔI = 1, extending from 2 + to 9 + are seen with no rotation-alignment. The purity of these bands and their persistence to such high spin establish them as an independent collective mode which is best described as a gamma-type vibration band in a deformed nucleus. In addition to all of the above bands, new bands are seen in 76 Kr and 74 Se. The nature of these bands is not presently known. 56 references

  3. Band tailing and efficiency limitation in kesterite solar cells

    Science.gov (United States)

    Gokmen, Tayfun; Gunawan, Oki; Todorov, Teodor K.; Mitzi, David B.

    2013-09-01

    We demonstrate that a fundamental performance bottleneck for hydrazine processed kesterite Cu2ZnSn(S,Se)4 (CZTSSe) solar cells with efficiencies reaching above 11% can be the formation of band-edge tail states, which quantum efficiency and photoluminescence data indicate is roughly twice as severe as in higher-performing Cu(In,Ga)(S,Se)2 devices. Low temperature time-resolved photoluminescence data suggest that the enhanced tailing arises primarily from electrostatic potential fluctuations induced by strong compensation and facilitated by a lower CZTSSe dielectric constant. We discuss the implications of the band tails for the voltage deficit in these devices.

  4. The temperature dependent amide I band of crystalline acetanilide

    International Nuclear Information System (INIS)

    Cruzeiro, Leonor; Freedman, Holly

    2013-01-01

    The temperature dependent anomalous peak in the amide I band of crystalline acetanilide is thought to be due to self-trapped states. On the contrary, according to the present model, the anomalous peak comes from the fraction of ACN molecules strongly hydrogen-bonded to a neighboring ACN molecule, and its intensity decreases because, on average, this fraction decreases as temperature increases. This model provides, for the first time, an integrated and theoretically consistent view of the temperature dependence of the full amide I band and a qualitative explanation of some of the features of nonlinear pump–probe experiments.

  5. The temperature dependent amide I band of crystalline acetanilide

    Energy Technology Data Exchange (ETDEWEB)

    Cruzeiro, Leonor [CCMAR, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Physics Department, FCT, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal); Freedman, Holly [CCMAR, Universidade do Algarve, Campus de Gambelas, 8005-139 Faro (Portugal)

    2013-10-01

    The temperature dependent anomalous peak in the amide I band of crystalline acetanilide is thought to be due to self-trapped states. On the contrary, according to the present model, the anomalous peak comes from the fraction of ACN molecules strongly hydrogen-bonded to a neighboring ACN molecule, and its intensity decreases because, on average, this fraction decreases as temperature increases. This model provides, for the first time, an integrated and theoretically consistent view of the temperature dependence of the full amide I band and a qualitative explanation of some of the features of nonlinear pump–probe experiments.

  6. The temperature dependent amide I band of crystalline acetanilide

    Science.gov (United States)

    Cruzeiro, Leonor; Freedman, Holly

    2013-10-01

    The temperature dependent anomalous peak in the amide I band of crystalline acetanilide is thought to be due to self-trapped states. On the contrary, according to the present model, the anomalous peak comes from the fraction of ACN molecules strongly hydrogen-bonded to a neighboring ACN molecule, and its intensity decreases because, on average, this fraction decreases as temperature increases. This model provides, for the first time, an integrated and theoretically consistent view of the temperature dependence of the full amide I band and a qualitative explanation of some of the features of nonlinear pump-probe experiments.

  7. Band engineering in transition metal dichalcogenides: Stacked versus lateral heterostructures

    International Nuclear Information System (INIS)

    Guo, Yuzheng; Robertson, John

    2016-01-01

    We calculate a large difference in the band alignments for transition metal dichalcogenide (TMD) heterojunctions when arranged in the stacked layer or lateral (in-plane) geometries, using direct supercell calculations. The stacked case follows the unpinned limit of the electron affinity rule, whereas the lateral geometry follows the strongly pinned limit of alignment of charge neutrality levels. TMDs therefore provide one of the few clear tests of band alignment models, whereas three-dimensional semiconductors give less stringent tests because of accidental chemical trends in their properties.

  8. Vortex excitations and identical superdeformed bands

    Energy Technology Data Exchange (ETDEWEB)

    Waddington, J C; Bhaduri, R K [McMaster Univ., Hamilton, ON (Canada). Dept. of Physics

    1992-08-01

    Striking relationships exist amongst the transition energies of the identical superdeformed bands (SDB). In this paper, the authors suggest that all of these bands in both the mass 150 and mass 190 regions can be explained as excitations of the specially stable doubly closed shell {sup 152}Dy. Typical of these bands is the case of {sup 153}Dy. Two excited SDB`s were observe which not only have a moment of inertia identical to that of {sup 152}Dy, but the transition energies are shifted by exactly {+-}1/4 of a rotational spacing. It is as though the spin 1/2 of the last neutron had been added directly to the angular momentum of the core, but the mass of this last particle had not contributed to the moment of inertia. The possibility is being investigated that the identical SDBs arise from an equivalent picture under the strong rotation of the specially stable {sup 152}Dy. The rotation renders the 3-dimensional space topologically nontrivial. The moment of inertia of {sup 192}Hg extrapolated to zero spin is identical to that of {sup 152}Dy at high spin. This suggests that a superfluid is formed as particles are added to {sup 152}Dy to make {sup 192}Hg. It is proposed that as the rotational frequency of {sup 192}Hg is increased, quantized vortices are formed, like vortices in superfluid {sup 4}He. These vortices lead to an additional alignment in{sup 192}Hg relative to the {sup 152} core, increasing as I{sup 2}, reaching a value of 4{Dirac_h} at I = 48. 3 refs., 3 figs.

  9. Highly efficient alkane oxidation catalyzed by [Mn(V)(N)(CN)4](2-). Evidence for [Mn(VII)(N)(O)(CN)4](2-) as an active intermediate.

    Science.gov (United States)

    Ma, Li; Pan, Yi; Man, Wai-Lun; Kwong, Hoi-Ki; Lam, William W Y; Chen, Gui; Lau, Kai-Chung; Lau, Tai-Chu

    2014-05-28

    The oxidation of various alkanes catalyzed by [Mn(V)(N)(CN)4](2-) using various terminal oxidants at room temperature has been investigated. Excellent yields of alcohols and ketones (>95%) are obtained using H2O2 as oxidant and CF3CH2OH as solvent. Good yields (>80%) are also obtained using (NH4)2[Ce(NO3)6] in CF3CH2OH/H2O. Kinetic isotope effects (KIEs) are determined by using an equimolar mixture of cyclohexane (c-C6H12) and cyclohexane-d12 (c-C6D12) as substrate. The KIEs are 3.1 ± 0.3 and 3.6 ± 0.2 for oxidation by H2O2 and Ce(IV), respectively. On the other hand, the rate constants for the formation of products using c-C6H12 or c-C6D12 as single substrate are the same. These results are consistent with initial rate-limiting formation of an active intermediate between [Mn(N)(CN)4](2-) and H2O2 or Ce(IV), followed by H-atom abstraction from cyclohexane by the active intermediate. When PhCH2C(CH3)2OOH (MPPH) is used as oxidant for the oxidation of c-C6H12, the major products are c-C6H11OH, c-C6H10O, and PhCH2C(CH3)2OH (MPPOH), suggesting heterolytic cleavage of MPPH to generate a Mn═O intermediate. In the reaction of H2O2 with [Mn(N)(CN)4](2-) in CF3CH2OH, a peak at m/z 628.1 was observed in the electrospray ionization mass spectrometry, which is assigned to the solvated manganese nitrido oxo species, (PPh4)[Mn(N)(O)(CN)4](-)·CF3CH2OH. On the basis of the experimental results the proposed mechanism for catalytic alkane oxidation by [Mn(V)(N)(CN)4](2-)/ROOH involves initial rate-limiting O-atom transfer from ROOH to [Mn(N)(CN)4](2-) to generate a manganese(VII) nitrido oxo active species, [Mn(VII)(N)(O)(CN)4](2-), which then oxidizes alkanes (R'H) via a H-atom abstraction/O-rebound mechanism. The proposed mechanism is also supported by density functional theory calculations.

  10. Changing optical band structure with single photons

    Science.gov (United States)

    Albrecht, Andreas; Caneva, Tommaso; Chang, Darrick E.

    2017-11-01

    Achieving strong interactions between individual photons enables a wide variety of exciting possibilities in quantum information science and many-body physics. Cold atoms interfaced with nanophotonic structures have emerged as a platform to realize novel forms of nonlinear interactions. In particular, when atoms are coupled to a photonic crystal waveguide, long-range atomic interactions can arise that are mediated by localized atom-photon bound states. We theoretically show that in such a system, the absorption of a single photon can change the band structure for a subsequent photon. This occurs because the first photon affects the atoms in the chain in an alternating fashion, thus leading to an effective period doubling of the system and a new optical band structure for the composite atom-nanophotonic system. We demonstrate how this mechanism can be engineered to realize a single-photon switch, where the first incoming photon switches the system from being highly transmissive to highly reflective, and analyze how signatures can be observed via non-classical correlations of the outgoing photon field.

  11. Spectra of γ rays feeding superdeformed bands

    International Nuclear Information System (INIS)

    Lauritsen, T.; Khoo, T.L.; Henry, R.G.

    1995-01-01

    The spectrum of γrays coincident with SD transitions contains the transitions which populate the SD band. This spectrum can provide information on the feeding mechanism and on the properties (moment of inertia, collectivity) of excited SD states. We used a model we developed to explain the feeding of SD bands, to calculate the spectrum of feeding γrays. The Monte Carlo simulations take into account the trigger conditions present in our Eurogam experiment. Both experimental and theoretical spectra contain a statistical component and a broad E2 peak (from transitions occurring between excited states in the SD well). There is good resemblance between the measured and calculated spectra although the calculated multiplicity of an E2 bump is low by ∼30%. Work is continuing to improve the quality of the fits, which will result in a better understanding of excited SD states. In addition, a model for the last steps, which cool the γ cascade into the SD yrast line, needs to be developed. A strong M1/E2 low-energy component, which we believe is responsible for this cooling, was observed

  12. Spectra of {gamma} rays feeding superdeformed bands

    Energy Technology Data Exchange (ETDEWEB)

    Lauritsen, T.; Khoo, T.L.; Henry, R.G. [and others

    1995-08-01

    The spectrum of {gamma}rays coincident with SD transitions contains the transitions which populate the SD band. This spectrum can provide information on the feeding mechanism and on the properties (moment of inertia, collectivity) of excited SD states. We used a model we developed to explain the feeding of SD bands, to calculate the spectrum of feeding {gamma}rays. The Monte Carlo simulations take into account the trigger conditions present in our Eurogam experiment. Both experimental and theoretical spectra contain a statistical component and a broad E2 peak (from transitions occurring between excited states in the SD well). There is good resemblance between the measured and calculated spectra although the calculated multiplicity of an E2 bump is low by {approximately}30%. Work is continuing to improve the quality of the fits, which will result in a better understanding of excited SD states. In addition, a model for the last steps, which cool the {gamma} cascade into the SD yrast line, needs to be developed. A strong M1/E2 low-energy component, which we believe is responsible for this cooling, was observed.

  13. Radiative transition probabilities for the main diatomic electronic systems of N2, N2+, NO, O2, CO, CO+, CN, C2 and H2 produced in plasma of atmospheric entry

    Science.gov (United States)

    Qin, Z.; Zhao, J. M.; Liu, L. H.

    2017-11-01

    Accurate radiative transition probabilities of diatomic electronic systems are required to calculate the discrete radiation of plasmas. However, most of the published transition probabilities are obtained using older spectroscopic constants and electronic transition moment functions (ETMFs), some of which deviates greatly from experimental data. Fortunately, a lot of new spectroscopic constants that include more anharmonic correction terms than the earlier ones have been published over the past few years. In this work, the Einstein coefficients, Franck-Condon factors and absorption band oscillator strengths are calculated for important diatomic radiative transition processes of N2-O2, CO2-N2 and H2 plasmas produced in entering into the atmosphere of Earth, Mars and Jupiter. The most up-to-date spectroscopic constants are selected to reconstruct the potential energy curves by the Rydberg-Klein-Rees (RKR) method. Then the vibrational wave functions are calculated through the resolution of the radial Schrödinger equation for such potential energy curves. These results, together with the latest "ab-initio" ETMFs derived from the literature are used to compute the square of electronic-vibrational transition moments, Einstein coefficients and absorption band oscillator strengths. Moreover, the Franck-Condon factors are determined with the obtained vibrational wave functions. In the supplementary material we present tables of the radiative transition probabilities for 40 band systems of N2, N2+, NO, O2, CO, CO+, CN, C2 and H2 molecules. In addition, the calculated radiative lifetimes are systematically validated by available experimental results.

  14. Band structure dynamics in indium wires

    Science.gov (United States)

    Chávez-Cervantes, M.; Krause, R.; Aeschlimann, S.; Gierz, I.

    2018-05-01

    One-dimensional indium wires grown on Si(111) substrates, which are metallic at high temperatures, become insulating below ˜100 K due to the formation of a charge density wave (CDW). The physics of this transition is not conventional and involves a multiband Peierls instability with strong interband coupling. This CDW ground state is readily destroyed with femtosecond laser pulses resulting in a light-induced insulator-to-metal phase transition. The current understanding of this transition remains incomplete, requiring measurements of the transient electronic structure to complement previous investigations of the lattice dynamics. Time- and angle-resolved photoemission spectroscopy with extreme ultraviolet radiation is applied to this end. We find that the transition from the insulating to the metallic band structure occurs within ˜660 fs, which is a fraction of the amplitude mode period. The long lifetime of the transient state (>100 ps) is attributed to trapping in a metastable state in accordance with previous work.

  15. Majorana flat bands in anisotropic systems

    Energy Technology Data Exchange (ETDEWEB)

    Mendler, Daniel; Kotetes, Panagiotis; Schoen, Gerd [Institut fuer theoretische Festkoerperphysik, Karlsruher Institut fuer Technologie (Germany)

    2015-07-01

    It has been recently proposed that topologically protected Majorana flat bands (MFBs) emerge in superconductors with nodal energy spectrum. In this work we introduce a new class of gapful superconductors, in which MFBs can occur due to strong anisotropy. The prototype system exhibiting this kind of behavior is the nematic p{sub x}+p{sub y} spinless superconductor, which supports an edge MFB with controllable bandwidth. Our proposal can be for instance experimentally implemented in topological superconductors engineered from i. semiconductors with tunable spin-orbit coupling or ii. topological insulator surfaces with intrinsic magnetic order in proximity to a conventional SC. By investigating the topological properties of both setups, we show that their unique features render them feasible platforms for manipulating the Majorana fermion bandstructure and realizing MFBs.

  16. Two band model for the cuprates

    Science.gov (United States)

    Liu, Shiu; White, Steven

    2009-03-01

    We use a numerical canonical transformation approach to derive an effective two-band model for the hole-doped cuprates, which keeps both oxygen and copper orbitals but removes double occupancy from each. A similar model was considered previously by Frenkel, Gooding, Shraiman, and Siggia (PRB 41, number 1, page 350). We compare the numerically derived model with previously obtained analytical results. In addition to the usual hopping terms between oxygens tpp and Cu-Cu exchange terms Jdd, the model also includes a strong copper-oxygen exchange interaction Jpd and a Kondo-like spin-flip oxygen-oxygen hopping term Kpdp. We use the density matrix renormalization group to study the charge, spin, and pairing properties of the derived model on ladder systems.

  17. S-band and X-band integrated PWT photoelectron linacs

    International Nuclear Information System (INIS)

    Yu, D.; Newsham, D.; Zeng, J.; Rosenzweig, J.

    2001-01-01

    A compact high-energy injector, which has been developed by DULY Research Inc., will have wide scientific, industrial, and medical applications. The new photoelectron injector integrates the photocathode directly into a multicell linear accelerator. By focusing the beam with solenoids or permanent magnets, and producing high current with low emittance, high brightness and low energy spread are achieved. In addition to providing a small footprint and improved beam quality in an integrated structure, the compact system considerably simplifies external subsystems required to operate the photoelectron linac, including rf power transport, beam focusing, vacuum and cooling. The photoelectron linac employs an innovative Plane-Wave-Transformer (PWT) design, which provides strong cell-to-cell coupling, relaxes manufacturing tolerances and facilitates the attachment of external ports to the compact structure with minimal field interference. DULY Research Inc. under the support of the DOE Small Business Innovation Research (SBIR) program, has developed, constructed and installed a 20-MeV, S-band compact electron source at UCLA. Cold test results for this device are presented. DULY Research is also actively engaged in the development of an X-band photoelectron linear accelerator in a SBIR project. When completed, the higher frequency structure will be approximately three times smaller. Design considerations for this device are discussed following the S-band cold test results

  18. K3[Fe(CN)6].3H2O supported on silica gel: An efficient and selective ...

    Indian Academy of Sciences (India)

    Department of Chemistry, Payame Noor University, 19395-4697 Tehran, I. R. of IRAN e-mail: ... K3[Fe(CN)6].3H2O, Silica gel; oxime; aldehyde; ketone. 1. Introduction .... ysis, hydrogenation, etc., using organic and inorganic reagents. Besides ...

  19. Effects of C/N controlled periphyton based organic farming of freshwater prawn on water quality parameters and biotic factors

    Directory of Open Access Journals (Sweden)

    Md. Rezoanul Haque

    2014-08-01

    Full Text Available The effects of C:N controlled periphyton based organic farming of freshwater prawn on water quality parameters and biotic factors were investigated. The experiment had two treatments: T1 and T2 each with three replications. Stocking density was maintained at 20,000 juveniles ha-1. In T1, only commercially available prawn feed was applied and in T2, a locally formulated and prepared feed containing 24% crude protein with C:N ratio close to 20 was used, and maize flour and bamboo side shoots were provided for maintaining C:N ratio 20.Mean values of water quality parameters did not vary significantly (P>0.05 between treatments. Periphytic biomass in terms of dry matter, ash free dry matter (AFDM and chlorophyll a showed significant difference (P<0.05 among different sampling months. Individual harvesting weight, individual weight gain, specific growth rates, gross and net yields of prawn were significantly higher (P<0.05 in T2 than T1. Therefore, it was concluded that freshwater prawn might consume periphyton biomass in C:N controlled periphyton based organic farming practices resulted a significantly (P<0.05 higher production of freshwater prawn than traditional farming.

  20. Synthesis, crystal structure, and vibrational spectra of the anhydrous lithium dicyanamide Li[N(CN){sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Reckeweg, Olaf [Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301 (United States); Institut fuer Anorganische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany); DiSalvo, Francis J. [Baker Laboratory, Department of Chemistry and Chemical Biology, Cornell University, Ithaca, NY 14853-1301 (United States); Schulz, Armin [Max-Planck-Institut fuer Festkoerperforschung, Heisenbergstrasse 1, 70569 Stuttgart (Germany); Blaschkowski, Bjoern; Schleid, Thomas [Institut fuer Anorganische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany); Jagiella, Stefan [Institut fuer Physikalische und Theoretische Chemie, Universitaet Stuttgart, Pfaffenwaldring 55, 70569 Stuttgart (Germany)

    2014-04-15

    Crystals of Li[N(CN){sub 2}] were synthesized from a metathesis reaction of stoichiometric amounts of aqueous solutions of Na[N(CN){sub 2}] and Li{sub 2}[SO{sub 4}] followed by subsequent treatment with ethanol and evaporation of the filtered-off solution at 80 C under normal atmospheric conditions. The single crystals of the title compound are transparent, colorless, and extremly hygroscopic. X-ray structure analysis showed that Li[N(CN){sub 2}] crystallizes in the monoclinic space group P2/c with the cell parameters a = 530.79(8) pm, b = 524.89(9) pm, c = 1149.77(17) pm, β = 101.551(7) , and Z = 4. The crystal structure contains Li{sup +} cations in both tetrahedral and octahedral nitrogen coordination of the boomerang-shaped [N≡C-N-C≡N]{sup -} anions. The vibrational spectra of Li[N(CN){sub 2}] are reported as well, together with ab initio calculations for geometry and harmonic frequencies of the free dicyanamide anion. (Copyright copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Effects of C/N ratio and substrate addition on natural food communities in freshwater prawn monoculture ponds

    NARCIS (Netherlands)

    Asaduzzaman, M.; Rahman, M.M.; Azim, M.E.; Islam, M.A.; Wahab, M.A.; Verdegem, M.C.J.; Verreth, J.A.J.

    2010-01-01

    An on-station trial was conducted to investigate the effects of three C/N ratios (10/1, 15/1 and 20/1) along with substrate presence or absence on natural food communities in freshwater prawn culture ponds. An experiment was carried out in 40 m2 ponds stocked with a stocking density of 2 prawn

  2. Franklin Medal and Bower prize awarded to C.N. Yang. On the Yang-Mills gauge field theory

    International Nuclear Information System (INIS)

    Ma Zhongqi

    1995-01-01

    C.N. Yang was awarded the Benjamin Franklin Medal and 1995 Bower Prize mainly for his fundamental work on nonabelian gauge field theory. A brief introduction to this theory and its important role in the development of physics is given

  3. iCN718, an Updated and Improved Genome-Scale Metabolic Network Reconstruction of Acinetobacter baumannii AYE.

    Science.gov (United States)

    Norsigian, Charles J; Kavvas, Erol; Seif, Yara; Palsson, Bernhard O; Monk, Jonathan M

    2018-01-01

    Acinetobacter baumannii has become an urgent clinical threat due to the recent emergence of multi-drug resistant strains. There is thus a significant need to discover new therapeutic targets in this organism. One means for doing so is through the use of high-quality genome-scale reconstructions. Well-curated and accurate genome-scale models (GEMs) of A. baumannii would be useful for improving treatment options. We present an updated and improved genome-scale reconstruction of A. baumannii AYE, named iCN718, that improves and standardizes previous A. baumannii AYE reconstructions. iCN718 has 80% accuracy for predicting gene essentiality data and additionally can predict large-scale phenotypic data with as much as 89% accuracy, a new capability for an A. baumannii reconstruction. We further demonstrate that iCN718 can be used to analyze conserved metabolic functions in the A. baumannii core genome and to build strain-specific GEMs of 74 other A. baumannii strains from genome sequence alone. iCN718 will serve as a resource to integrate and synthesize new experimental data being generated for this urgent threat pathogen.

  4. Rainfall - CN (Curve Number relationships in a tropical rainforest microbasin within the Panamá Canal watershed

    Directory of Open Access Journals (Sweden)

    José R. Fábrega D

    2012-01-01

    Full Text Available Relaciones de Precipitación (P y Número de Curva (CN para diferentesrangos de flujo base obtenidas dentro de la cuenca alta del Río Chagres fueron aplicadas a una microcuenca de 6.5 Ha localizada dentro de la cuenca del Canal de Panamá. Estas relaciones estiman valores de CN a partir de los datos de P empleando una ecuación establecida por Calvo et al (10. Esta ecuación usa k y CN∞ como parámetros de ajuste. Datos de precipitación/escorrentía de la microcuenca, colectados en un período de 6 meses fueron analizados. Estos análisis mostraron que los valores de CN en la microcuenca son más cercanos a los valores de CN predichos por la ecuación correspondiente al rango más bajo de los flujos base (14-42 m3/s de la cuenca alta del Río Chagres. Estos resultados se explican si consideramos no los valores absolutos del flujo base Qbase, sino los valores relativos de este parámetro con respecto al área de la cuenca bajo estudio.

  5. An efficient solvent-free synthesis of imidazolines and benzimidazoles using K 4[Fe(CN 6] catalysis

    Directory of Open Access Journals (Sweden)

    Kabeer A. Shaikh

    2012-01-01

    Full Text Available Imidazolines and Benzimidazoles have been efficiently synthesized in high yields by treatment of 1,2-diamine with aldehydes using the metal co-ordinate complex K 4[Fe(CN 6] as a catalysis. The method was carried out under solvent free condition via oxidation of carbon-nitrogen bond. The process is green, mild and inexpensive.

  6. Effects of styrene unit on molecular conformation and spectral properties of CNsbnd PhCHdbnd NPhCHdbnd CHPhsbnd CN

    Science.gov (United States)

    Fang, Zhengjun; Wu, Feng; Jiao, Yingchun; Wang, Nanfang; Au, Chaktong; Cao, Chenzhong; Yi, Bing

    2018-05-01

    Compound CN-PhCH=NPhCH=CHPh-CN with both stilbene and benzylidene aniline units was synthesized, and studied from the viewpoint of molecular conformation and spectroscopic property by a combined use of experimental and computational methods. The maximum UV absorption wavelength (λmax) of the compound in ethanol, acetonitrile, chloroform and cyclohexane solvents were measured, and the 13C NMR chemical shift value δC(Cdbnd N) in chloroform-d was determined. The crystal structure of the compound was determined by X-ray diffraction. The frontier molecular orbital was calculated by density functional theory method. The results show that the UV absorption spectrum of the titled compound is similar to those of Schiff bases, while there is a larger red shift of λmax comparing to that of CN-PhCH=NPh-CN. Moreover, the molecular configuration of the titled compound relative to Cdbnd N is anti-form, having a more obvious twisted structure. The spectral and structural behaviors are further supported by the results of frontier molecular orbital analyses, NBO, electrostatic potentials and TD-DFT calculations. The study provides deeper insights into the molecular conformation of Schiff bases.

  7. Strongly Correlated Systems Theoretical Methods

    CERN Document Server

    Avella, Adolfo

    2012-01-01

    The volume presents, for the very first time, an exhaustive collection of those modern theoretical methods specifically tailored for the analysis of Strongly Correlated Systems. Many novel materials, with functional properties emerging from macroscopic quantum behaviors at the frontier of modern research in physics, chemistry and materials science, belong to this class of systems. Any technique is presented in great detail by its own inventor or by one of the world-wide recognized main contributors. The exposition has a clear pedagogical cut and fully reports on the most relevant case study where the specific technique showed to be very successful in describing and enlightening the puzzling physics of a particular strongly correlated system. The book is intended for advanced graduate students and post-docs in the field as textbook and/or main reference, but also for other researchers in the field who appreciates consulting a single, but comprehensive, source or wishes to get acquainted, in a as painless as po...

  8. Strongly correlated systems numerical methods

    CERN Document Server

    Mancini, Ferdinando

    2013-01-01

    This volume presents, for the very first time, an exhaustive collection of those modern numerical methods specifically tailored for the analysis of Strongly Correlated Systems. Many novel materials, with functional properties emerging from macroscopic quantum behaviors at the frontier of modern research in physics, chemistry and material science, belong to this class of systems. Any technique is presented in great detail by its own inventor or by one of the world-wide recognized main contributors. The exposition has a clear pedagogical cut and fully reports on the most relevant case study where the specific technique showed to be very successful in describing and enlightening the puzzling physics of a particular strongly correlated system. The book is intended for advanced graduate students and post-docs in the field as textbook and/or main reference, but also for other researchers in the field who appreciate consulting a single, but comprehensive, source or wishes to get acquainted, in a as painless as possi...

  9. Strongly correlated systems experimental techniques

    CERN Document Server

    Mancini, Ferdinando

    2015-01-01

    The continuous evolution and development of experimental techniques is at the basis of any fundamental achievement in modern physics. Strongly correlated systems (SCS), more than any other, need to be investigated through the greatest variety of experimental techniques in order to unveil and crosscheck the numerous and puzzling anomalous behaviors characterizing them. The study of SCS fostered the improvement of many old experimental techniques, but also the advent of many new ones just invented in order to analyze the complex behaviors of these systems. Many novel materials, with functional properties emerging from macroscopic quantum behaviors at the frontier of modern research in physics, chemistry and materials science, belong to this class of systems. The volume presents a representative collection of the modern experimental techniques specifically tailored for the analysis of strongly correlated systems. Any technique is presented in great detail by its own inventor or by one of the world-wide recognize...

  10. 47 CFR 90.531 - Band plan.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Band plan. 90.531 Section 90.531...-805 MHz Bands § 90.531 Band plan. This section sets forth the band plan for the 763-775 MHz and 793... and portables subject to Commission-approved regional planning committee regional plans. Transmitter...

  11. Flavour Democracy in Strong Unification

    CERN Document Server

    Abel, S A; Abel, Steven; King, Steven

    1998-01-01

    We show that the fermion mass spectrum may naturally be understood in terms of flavour democratic fixed points in supersymmetric theories which have a large domain of attraction in the presence of "strong unification". Our approach provides an alternative to the approximate Yukawa texture zeroes of the Froggatt-Nielsen mechanism. We discuss a particular model based on a broken gauged $SU(3)_L\\times SU(3)_R$ family symmetry which illustrates our approach.

  12. Effect of Spin-Crossover-Induced Pore Contraction on CO2–Host Interactions in the Porous Coordination Polymers [Fe(pyrazine)M(CN)4] (M = Ni, Pt)

    Energy Technology Data Exchange (ETDEWEB)

    Culp, Jeffrey T; Chen, De-Li; Liu, Jinchen; Chirdon, Danielle; Kauffman, Kristi; Goodman, Angela; Johnson, J Karl

    2013-02-01

    Variable-temperature in situ ATR-FTIR spectra are presented for the porous spin-crossover compounds [Fe(pyrazine)Ni(CN)4] and [Fe(pyrazine)Pt(CN)4] under CO2 pressures of up to 8 bar. Significant shifts in the ν3 and ν2 IR absorption bands of adsorbed CO2 are observed as the host materials undergo transition between low- and high-spin states. Computational models used to determine the packing arrangement of CO2 within the pore structures show a preferred orientation of one of the adsorbed CO2 molecules with close O=C=O···H contacts with the pyrazine pillar ligands. The interaction is a consequence of the commensurate distance of the inter-pyrazine separations and the length of the CO2 molecule, which allows the adsorbed CO2 to effectively bridge the pyrazine pillars in the structure. The models were used to assign the distinct shifts in the IR absorption bands of the adsorbed CO2 that arise from changes in the O=C=O···H contacts that strengthen and weaken in correlation with changes in the Fe–N bond lengths as the spin state of Fe changes. The results indicate that spin-crossover compounds can function as a unique type of flexible sorbent in which the pore contractions associated with spin transition can affect the strength of CO2–host interactions.

  13. String dynamics at strong coupling

    International Nuclear Information System (INIS)

    Hull, C.M.

    1996-01-01

    The dynamics of superstring, supergravity and M-theories and their compactifications are probed by studying the various perturbation theories that emerge in the strong and weak-coupling limits for various directions in coupling constant space. The results support the picture of an underlying non-perturbative theory that, when expanded perturbatively in different coupling constants, gives different perturbation theories, which can be perturbative superstring theories or superparticle theories. The p-brane spectrum is considered in detail and a criterion found to establish which p-branes govern the strong-coupling dynamics. In many cases there are competing conjectures in the literature, and this analysis decides between them. In other cases, new results are found. The chiral 6-dimensional theory resulting from compactifying the type IIB string on K 3 is studied in detail and it is found that certain strong-coupling limits appear to give new theories, some of which hint at the possibility of a 12-dimensional origin. (orig.)

  14. Metaphyseal bands in osteogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Suresh S

    2010-01-01

    Full Text Available An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as "zebra lines."

  15. Metaphyseal bands in osteogenesis imperfecta

    International Nuclear Information System (INIS)

    Suresh, SS; Thomas, John K

    2010-01-01

    An increasing number of patients with osteogenesis imperfecta are undergoing pamidronate therapy to prevent the incidence of fragility fractures. The authors herein report a child aged 3 years who received five cycles of pamidronate, resulting in metaphyseal bands, known as “zebra lines.”

  16. Quantitative effects of composting state variables on C/N ratio through GA-aided multivariate analysis.

    Science.gov (United States)

    Sun, Wei; Huang, Guo H; Zeng, Guangming; Qin, Xiaosheng; Yu, Hui

    2011-03-01

    It is widely known that variation of the C/N ratio is dependent on many state variables during composting processes. This study attempted to develop a genetic algorithm aided stepwise cluster analysis (GASCA) method to describe the nonlinear relationships between the selected state variables and the C/N ratio in food waste composting. The experimental data from six bench-scale composting reactors were used to demonstrate the applicability of GASCA. Within the GASCA framework, GA searched optimal sets of both specified state variables and SCA's internal parameters; SCA established statistical nonlinear relationships between state variables and the C/N ratio; to avoid unnecessary and time-consuming calculation, a proxy table was introduced to save around 70% computational efforts. The obtained GASCA cluster trees had smaller sizes and higher prediction accuracy than the conventional SCA trees. Based on the optimal GASCA tree, the effects of the GA-selected state variables on the C/N ratio were ranged in a descending order as: NH₄+-N concentration>Moisture content>Ash Content>Mean Temperature>Mesophilic bacteria biomass. Such a rank implied that the variation of ammonium nitrogen concentration, the associated temperature and the moisture conditions, the total loss of both organic matters and available mineral constituents, and the mesophilic bacteria activity, were critical factors affecting the C/N ratio during the investigated food waste composting. This first application of GASCA to composting modelling indicated that more direct search algorithms could be coupled with SCA or other multivariate analysis methods to analyze complicated relationships during composting and many other environmental processes. Copyright © 2010 Elsevier B.V. All rights reserved.

  17. The Use of Asymptotic Functions for Determining Empirical Values of CN Parameter in Selected Catchments of Variable Land Cover

    Science.gov (United States)

    Wałęga, Andrzej; Młyński, Dariusz; Wachulec, Katarzyna

    2017-12-01

    The aim of the study was to assess the applicability of asymptotic functions for determining the value of CN parameter as a function of precipitation depth in mountain and upland catchments. The analyses were carried out in two catchments: the Rudawa, left tributary of the Vistula, and the Kamienica, right tributary of the Dunajec. The input material included data on precipitation and flows for a multi-year period 1980-2012, obtained from IMGW PIB in Warsaw. Two models were used to determine empirical values of CNobs parameter as a function of precipitation depth: standard Hawkins model and 2-CN model allowing for a heterogeneous nature of a catchment area. The study analyses confirmed that asymptotic functions properly described P-CNobs relationship for the entire range of precipitation variability. In the case of high rainfalls, CNobs remained above or below the commonly accepted average antecedent moisture conditions AMCII. The study calculations indicated that the runoff amount calculated according to the original SCS-CN method might be underestimated, and this could adversely affect the values of design flows required for the design of hydraulic engineering projects. In catchments with heterogeneous land cover, the results of CNobs were more accurate when 2-CN model was used instead of the standard Hawkins model. 2-CN model is more precise in accounting for differences in runoff formation depending on retention capacity of the substrate. It was also demonstrated that the commonly accepted initial abstraction coefficient λ = 0.20 yielded too big initial loss of precipitation in the analyzed catchments and, therefore, the computed direct runoff was underestimated. The best results were obtained for λ = 0.05.

  18. Thermodynamics of many-band superconductors

    International Nuclear Information System (INIS)

    Waelte, A.

    2006-01-01

    In the present thesis the microscopical properties of the superconducting state of MgCNi 3 , MgB 2 , and some rare earth-transition metal borocarbides are studied by means of measurements of the specific heat. Furthermore the frequency spectrum of the lattice vibrations is estimated. The energy gap of the superconducting state can be determined from the specific heat of the superconducting state, which yields as like as the upper critical mafnetic field H c2 (0) hints on the electron-phonon coupling. From the analysis of these results and the comparison with results from transport measurements as well as the tunnel and point-contact spectroscopy can be concluded, how far the BCS model of superconductivity must be modified in order to be able to describe the superconducting state of the studied compounds. Studies on MgCNi 3 , which lies near a magnetic instability, show that occurring magnetic fluctuations have a bisection of the superconducting transition temperature T C as consequence. The under this aspect relatively high value of T C =7 K is a consequence of strong electron-phonon coupling, which is essentailly carried by nickel vibrations stabilized by carbon. A for the first time observed distinct anomaly in the specific heat of the classical many-band superconductor MgB 2 (here with pure 10 B) at about T c /4=10 K can be understood by means of a two-band model for the case of especially weak coupling between both bands. The analysis of the specific heat of the superconducting phase of the non-magnetic rare earth-nickel borocarbide YNi 2 B 2 C and LuNi 2 B 2 C leads to the conclusion thet visible effects of the many-band electron system are dependent on the mass on the position both of the rare earth and the transition metal. The signal of the superconducting phase transformation visible in the specific heat of the antiferromagnetic HoNi 2 B 2 C is smaller than expected

  19. Electrocatalytic oxidation of K4[Fe(CN)6] by metal-reducing bacteriumShewanella oneidensis MR-1

    DEFF Research Database (Denmark)

    Zheng, Zhiyong; Xiao, Yong; Wu, Ranran

    2017-01-01

    of an inorganic redox compound K4[Fe(CN)6]. A pair of symmetric peak in the cyclic voltammetry (CV) of K4[Fe(CN)6] were found on bare glassy carbon electrode (GCE). Surprisingly, when the GCE is coated MR-1, the anodic peak almost sustained at the same level; while the cathodic peak apparently shrunk. We...

  20. Search for excited superdeformed bands in {sup 151}Dy

    Energy Technology Data Exchange (ETDEWEB)

    Nisius, D.; Janssens, R.V.F.; Crowell, B. [and others

    1995-08-01

    Following the first report of superdeformed (SD) bands with identical transition energies in the pairs ({sup 151}Tb*,{sup 152}Dy), ({sup 150}Gd*, {sup 151}Tb) and ({sup 153}Dy*, {sup 152}Dy) (where * denotes an excited SD band), it was proposed by Nazarewicz et al. that the observations could be understood in a strong-coupling approach if pseudo SU(3) symmetry were invoked. In this model there are three limiting values of the decoupling parameter; i.e. a = 0, {plus_minus}1. In the first two cases mentioned above the pairs of bands have nearly identical transition energies and are interpreted as proton excitations involving the [200]1/2 pseudospin orbital coupled to the {sup 152}Dy core, for which the value of the decoupling parameter is calculated to be a =+1.

  1. New bands and spin-parity assignments in 111Ru

    International Nuclear Information System (INIS)

    Urban, W.; Rzaca-Urban, T.; Droste, C.; Rohozinski, S.G.; Durell, J.L.; Phillips, W.R.; Smith, A.G.; Varley, B.J.; Schulz, N.; Ahmad, I.; Pinston, J.A.

    2004-01-01

    The 111 Ru nucleus, populated in the spontaneous fission of 248 Cm has been studied by means of prompt gamma spectroscopy using the EUROGAM2 array. Spin and parity assignments, based on angular correlations, linear polarization, and conversion coefficient measurements differ from those available in the literature. New bands are reported, which incorporate γ transitions seen previously but not placed in the scheme of 111 Ru or placed incorrectly. The bands are interpreted as neutron excitations into subshells originating predominantly from the h 11/2 , g 7/2 and s 1/2 spherical orbitals. The s 1/2 band, strongly mixed with the d 3/2 , d 5/2 and g 7/2 configurations, is observed for the first time in this region. (orig.)

  2. PREFACE: Strongly correlated electron systems Strongly correlated electron systems

    Science.gov (United States)

    Saxena, Siddharth S.; Littlewood, P. B.

    2012-07-01

    This special section is dedicated to the Strongly Correlated Electron Systems Conference (SCES) 2011, which was held from 29 August-3 September 2011, in Cambridge, UK. SCES'2011 is dedicated to 100 years of superconductivity and covers a range of topics in the area of strongly correlated systems. The correlated electronic and magnetic materials featured include f-electron based heavy fermion intermetallics and d-electron based transition metal compounds. The selected papers derived from invited presentations seek to deepen our understanding of the rich physical phenomena that arise from correlation effects. The focus is on quantum phase transitions, non-Fermi liquid phenomena, quantum magnetism, unconventional superconductivity and metal-insulator transitions. Both experimental and theoretical work is presented. Based on fundamental advances in the understanding of electronic materials, much of 20th century materials physics was driven by miniaturisation and integration in the electronics industry to the current generation of nanometre scale devices. The achievements of this industry have brought unprecedented advances to society and well-being, and no doubt there is much further to go—note that this progress is founded on investments and studies in the fundamentals of condensed matter physics from more than 50 years ago. Nevertheless, the defining challenges for the 21st century will lie in the discovery in science, and deployment through engineering, of technologies that can deliver the scale needed to have an impact on the sustainability agenda. Thus the big developments in nanotechnology may lie not in the pursuit of yet smaller transistors, but in the design of new structures that can revolutionise the performance of solar cells, batteries, fuel cells, light-weight structural materials, refrigeration, water purification, etc. The science presented in the papers of this special section also highlights the underlying interest in energy-dense materials, which

  3. Near-field strong coupling of single quantum dots.

    Science.gov (United States)

    Groß, Heiko; Hamm, Joachim M; Tufarelli, Tommaso; Hess, Ortwin; Hecht, Bert

    2018-03-01

    Strong coupling and the resultant mixing of light and matter states is an important asset for future quantum technologies. We demonstrate deterministic room temperature strong coupling of a mesoscopic colloidal quantum dot to a plasmonic nanoresonator at the apex of a scanning probe. Enormous Rabi splittings of up to 110 meV are accomplished by nanometer-precise positioning of the quantum dot with respect to the nanoresonator probe. We find that, in addition to a small mode volume of the nanoresonator, collective coherent coupling of quantum dot band-edge states and near-field proximity interaction are vital ingredients for the realization of near-field strong coupling of mesoscopic quantum dots. The broadband nature of the interaction paves the road toward ultrafast coherent manipulation of the coupled quantum dot-plasmon system under ambient conditions.

  4. Atoms in strong laser fields

    International Nuclear Information System (INIS)

    L'Huillier, A.

    2002-01-01

    When a high-power laser focuses into a gas of atoms, the electromagnetic field becomes of the same magnitude as the Coulomb field which binds a 1s electron in a hydrogen atom. 3 highly non-linear phenomena can happen: 1) ATI (above threshold ionization): electrons initially in the ground state absorb a large number of photons, many more than the minimum number required for ionization; 2) multiple ionization: many electrons can be emitted one at a time, in a sequential process, or simultaneously in a mechanism called direct or non-sequential; and 3) high order harmonic generation (HHG): efficient photon emission in the extreme ultraviolet range, in the form of high-order harmonics of the fundamental laser field can occur. The theoretical problem consists in solving the time dependent Schroedinger equation (TDSE) that describes the interaction of a many-electron atom with a laser field. A number of methods have been proposed to solve this problem in the case of a hydrogen atom or a single-active electron atom in a strong laser field. A large effort is presently being devoted to go beyond the single-active approximation. The understanding of the physics of the interaction between atoms and strong laser fields has been provided by a very simple model called ''simple man's theory''. A unified view of HHG, ATI, and non-sequential ionization, originating from the simple man's model and the strong field approximation, expressed in terms of electrons trajectories or quantum paths is slowly emerging. (A.C.)

  5. Observations of 40-70 micron bands of ice in IRAS 09371 + 1212 and other stars

    Science.gov (United States)

    Omont, A.; Forveille, T.; Moseley, S. H.; Glaccum, W. J.; Harvey, P. M.; Likkel, L.; Loewenstein, R. F.; Lisse, C. M.

    1990-01-01

    IRAS 09371 + 1212 is still an absolutely unique object. This M giant star, with circumstellar CO and a spectacular bipolar nebula, displays unique IRAS FIR colors which had been attributed to strong emission in the 40-70-micron bands of ice, as subsequently supported by the observation of a strong 3.1-micron absorption band. The results of the KAO observations have confirmed its unusual nature: the far-infrared bands of ice are by far the strongest known. Its dust temperature, 50 K or less, is by far the lowest known for a late-type circumstellar envelope.

  6. Rydberg atoms in strong fields

    International Nuclear Information System (INIS)

    Kleppner, D.; Tsimmerman, M.

    1985-01-01

    Experimental and theoretical achievements in studying Rydberg atoms in external fields are considered. Only static (or quasistatic) fields and ''one-electron'' atoms, i.e. atoms that are well described by one-electron states, are discussed. Mainly behaviour of alkali metal atoms in electric field is considered. The state of theoretical investigations for hydrogen atom in magnetic field is described, but experimental data for atoms of alkali metals are presented as an illustration. Results of the latest experimental and theoretical investigations into the structure of Rydberg atoms in strong fields are presented

  7. Strong versions of Bell's theorem

    International Nuclear Information System (INIS)

    Stapp, H.P.

    1994-01-01

    Technical aspects of a recently constructed strong version of Bell's theorem are discussed. The theorem assumes neither hidden variables nor factorization, and neither determinism nor counterfactual definiteness. It deals directly with logical connections. Hence its relationship with modal logic needs to be described. It is shown that the proof can be embedded in an orthodox modal logic, and hence its compatibility with modal logic assured, but that this embedding weakens the theorem by introducing as added assumptions the conventionalities of the particular modal logic that is adopted. This weakening is avoided in the recent proof by using directly the set-theoretic conditions entailed by the locality assumption

  8. Strongly interacting light dark matter

    International Nuclear Information System (INIS)

    Bruggisser, Sebastian; Riva, Francesco; Urbano, Alfredo

    2016-07-01

    In the presence of approximate global symmetries that forbid relevant interactions, strongly coupled light Dark Matter (DM) can appear weakly coupled at small-energy and generate a sizable relic abundance. Fundamental principles like unitarity restrict these symmetries to a small class, where the leading interactions are captured by effective operators up to dimension-8. Chiral symmetry, spontaneously broken global symmetries and non-linearly realized supersymmetry are examples of this. Their DM candidates (composite fermions, pseudo-Nambu-Goldstone Bosons and Goldstini) are interesting targets for LHC missing-energy searches.

  9. Weak consistency and strong paraconsistency

    Directory of Open Access Journals (Sweden)

    Gemma Robles

    2009-11-01

    Full Text Available In a standard sense, consistency and paraconsistency are understood as, respectively, the absence of any contradiction and as the absence of the ECQ (“E contradictione quodlibet” rule that allows us to conclude any well formed formula from any contradiction. The aim of this paper is to explain the concepts of weak consistency alternative to the standard one, the concepts of paraconsistency related to them and the concept of strong paraconsistency, all of which have been defined by the author together with José M. Méndez.

  10. On the strong CP problem

    Energy Technology Data Exchange (ETDEWEB)

    Dowrick, N.J. (Dept. of Physics, Oxford (United Kingdom)); McDougall, N.A. (National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan))

    1992-07-09

    We show that two well-known solutions to the strong CP problem, the axion and a massless quark, may be understood in terms of the mechanism recently proposed by Samuel where long-range interactions between topological charges may be responsible for the removal of CP violation. We explain how the axion and a QCD meson (identified as the {eta}' if all quarks are massless) suppress fluctuations in global topological charge by almost identical dynamical although the masses, couplings and relevant length scales are very different. Furthermore, we elucidate the precise origin of the {eta}' mass. (orig.).

  11. Scalar strong interaction hadron theory

    CERN Document Server

    Hoh, Fang Chao

    2015-01-01

    The scalar strong interaction hadron theory, SSI, is a first principles' and nonlocal theory at quantum mechanical level that provides an alternative to low energy QCD and Higgs related part of the standard model. The quark-quark interaction is scalar rather than color-vectorial. A set of equations of motion for mesons and another set for baryons have been constructed. This book provides an account of the present state of a theory supposedly still at its early stage of development. This work will facilitate researchers interested in entering into this field and serve as a basis for possible future development of this theory.

  12. Estimation of strong ground motion

    International Nuclear Information System (INIS)

    Watabe, Makoto

    1993-01-01

    Fault model has been developed to estimate a strong ground motion in consideration of characteristics of seismic source and propagation path of seismic waves. There are two different approaches in the model. The first one is a theoretical approach, while the second approach is a semi-empirical approach. Though the latter is more practical than the former to be applied to the estimation of input motions, it needs at least the small-event records, the value of the seismic moment of the small event and the fault model of the large event

  13. Strong Mechanoluminescence from Oxynitridosilicate Phosphors

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lin; Xu Chaonan; Yamada, Hiroshi, E-mail: cn-xu@aist.go.jp [National Institute of Advanced Industrial Science and Technology (AIST), 807-1 Shuku, Tosu, Saga 841-0052 (Japan)

    2011-10-29

    We successfully developed a novel Mechanoluminescence (ML) material with water resistance, oxynitridosilicate; BaSi{sub 2}O{sub 2}N{sub 2}: Eu{sup 2+}. The crystal structure, photoluminescence (PL) and ML properties were characterized. The ML of BaSi{sub 2}O{sub 2}N{sub 2}: Eu{sup 2+} is so strong that the blue-green emission can be observed by the naked eyes clearly. In addition, it shows superior water resistance property. No changes were found in the ML intensities during the total water treatment test.

  14. The infrared emission bands. III. Southern IRAS sources.

    Science.gov (United States)

    Cohen, M; Tielens, A G; Bregman, J; Witteborn, F C; Rank, D M; Allamandola, L J; Wooden, D H; de Muizon, M

    1989-06-01

    We present airborne 5-8 micrometers spectra of southern IRAS sources which reveal strong polycyclic aromatic hydrocarbon (PAH) emission features. The good correlation between the bands, in particular the dominant 6.2 and "7.7" micrometers features, strongly imply a common carrier, reinforcing the PAH hypothesis. However, small but detectable spectral variations exist. Planetaries have a distinctly different ratio of I(6.2)/I(7.7) than other nebulae, accompanied by a redward shift in the actual wavelength of the "7.7" micrometers peak. Further, we have detected a new feature, previously predicted from laboratory spectra of PAH molecules, at 5.2 micrometers in many of these sources. Spectra of two rare [WC 10] planetary nebular nuclei indicate a very prominent plateau of emission, linking the 6.2 and 7.7 micrometers bands. Several of our sources show definite evidence for emission structure between 14 and 23 micrometers in their IRAS Low-Resolution Spectral Atlas spectra: we attribute this structure to PAH bands. too. We have defined the "generic" spectrum of emission bands relating the mean intensities of each band to that of the strongest, near 7.7 micrometers. We have added three more planetary or protoplanetary nebulae to our correlation between 7.7 micrometers band intensity and nebular gas phase C/O ratio, namely NGC 6302, HR 4049, and the highly carbon-rich [WC 10] nucleus, CPD--56 degrees 8032. For the latter we have determined a ratio for C/O of approximately 4.8 from IUE observations. The good correlation between the intensity ratio of the "7.7" micrometers feature relative to the far-infrared dust continuum and nebular C/O also supports a carbonaceous carrier for these emission features.

  15. Cloning, Expression Profiling and Functional Analysis of CnHMGS, a Gene Encoding 3-hydroxy-3-Methylglutaryl Coenzyme A Synthase from Chamaemelum nobile

    Directory of Open Access Journals (Sweden)

    Shuiyuan Cheng

    2016-03-01

    Full Text Available Roman chamomile (Chamaemelum nobile L. is renowned for its production of essential oils, which major components are sesquiterpenoids. As the important enzyme in the sesquiterpenoid biosynthesis pathway, 3-hydroxy-3-methylglutaryl coenzyme A synthase (HMGS catalyze the crucial step in the mevalonate pathway in plants. To isolate and identify the functional genes involved in the sesquiterpene biosynthesis of C. nobile L., a HMGS gene designated as CnHMGS (GenBank Accession No. KU529969 was cloned from C. nobile. The cDNA sequence of CnHMGS contained a 1377 bp open reading frame encoding a 458-amino-acid protein. The sequence of the CnHMGS protein was highly homologous to those of HMGS proteins from other plant species. Phylogenetic tree analysis revealed that CnHMGS clustered with the HMGS of Asteraceae in the dicotyledon clade. Further functional complementation of CnHMGS in the mutant yeast strain YSC6274 lacking HMGS activity demonstrated that the cloned CnHMGS cDNA encodes a functional HMGS. Transcript profile analysis indicated that CnHMGS was preferentially expressed in flowers and roots of C. nobile. The expression of CnHMGS could be upregulated by exogenous elicitors, including methyl jasmonate and salicylic acid, suggesting that CnHMGS was elicitor-responsive. The characterization and expression analysis of CnHMGS is helpful to understand the biosynthesis of sesquiterpenoid in C. nobile at the molecular level and also provides molecular wealth for the biotechnological improvement of this important medicinal plant.

  16. Effective lagrangian for strong interactions

    International Nuclear Information System (INIS)

    Jain, P.

    1988-01-01

    We attempt to construct a realistic phenomenological Lagrangian in order to describe strong interactions. This is in general a very complicated problem and we shall explore its various aspects. We first include the vector mesons by writing down the most general chiral invariant terms proportional to the Levi-Civita symbol ε μναβ . These terms involve three unknown coefficients, which are calculated by using the experimental results of strong interaction processes. We then calculate the static nucleon properties by finding the solitonic excitations of this model. The results turn out to be, as is also the case for most other vector-pseudoscalar Lagrangians, better than the Skyrme model but are still somewhat different from the experiments. Another aspect that we shall study is the incorporation of scale anomaly of QCD into the Skyrme model. We thus introduce a scalar glueball in our Lagrangian. Here we find an interesting result that the effective glue field dynamically forms a bag for the soliton. Depending on the values of the parameters, we get either a deep bag or a shallow bag. However by including the scalar meson, we find that to get realistic scalar sector we must have the shallow bag. Finally we show some intriguing connections between the chiral quark model, in which the nucleon is described as a solitonic excitation, and the ordinary potential binding quark model

  17. EDITORIAL: Strongly correlated electron systems Strongly correlated electron systems

    Science.gov (United States)

    Ronning, Filip; Batista, Cristian

    2011-03-01

    Strongly correlated electrons is an exciting and diverse field in condensed matter physics. This special issue aims to capture some of that excitement and recent developments in the field. Given that this issue was inspired by the 2010 International Conference on Strongly Correlated Electron Systems (SCES 2010), we briefly give some history in order to place this issue in context. The 2010 International Conference on Strongly Correlated Electron Systems was held in Santa Fe, New Mexico, a reunion of sorts from the 1989 International Conference on the Physics of Highly Correlated Electron Systems that also convened in Santa Fe. SCES 2010—co-chaired by John Sarrao and Joe Thompson—followed the tradition of earlier conferences, in this century, hosted by Buzios (2008), Houston (2007), Vienna (2005), Karlsruhe (2004), Krakow (2002) and Ann Arbor (2001). Every three years since 1997, SCES has joined the International Conference on Magnetism (ICM), held in Recife (2000), Rome (2003), Kyoto (2006) and Karlsruhe (2009). Like its predecessors, SCES 2010 topics included strongly correlated f- and d-electron systems, heavy-fermion behaviors, quantum-phase transitions, non-Fermi liquid phenomena, unconventional superconductivity, and emergent states that arise from electronic correlations. Recent developments from studies of quantum magnetism and cold atoms complemented the traditional subjects and were included in SCES 2010. 2010 celebrated the 400th anniversary of Santa Fe as well as the birth of astronomy. So what's the connection to SCES? The Dutch invention of the first practical telescope and its use by Galileo in 1610 and subsequent years overturned dogma that the sun revolved about the earth. This revolutionary, and at the time heretical, conclusion required innovative combinations of new instrumentation, observation and mathematics. These same combinations are just as important 400 years later and are the foundation of scientific discoveries that were discussed

  18. Strong Selective Adsorption of Polymers.

    Science.gov (United States)

    Ge, Ting; Rubinstein, Michael

    2015-06-09

    A scaling theory is developed for selective adsorption of polymers induced by the strong binding between specific monomers and complementary surface adsorption sites. By "selective" we mean specific attraction between a subset of all monomers, called "sticky", and a subset of surface sites, called "adsorption sites". We demonstrate that, in addition to the expected dependence on the polymer volume fraction ϕ bulk in the bulk solution, selective adsorption strongly depends on the ratio between two characteristic length scales, the root-mean-square distance l between neighboring sticky monomers along the polymer, and the average distance d between neighboring surface adsorption sites. The role of the ratio l / d arises from the fact that a polymer needs to deform to enable the spatial commensurability between its sticky monomers and the surface adsorption sites for selective adsorption. We study strong selective adsorption of both telechelic polymers with two end monomers being sticky and multisticker polymers with many sticky monomers between sticky ends. For telechelic polymers, we identify four adsorption regimes at l / d 1, we expect that the adsorption layer at exponentially low ϕ bulk consists of separated unstretched loops, while as ϕ bulk increases the layer crosses over to a brush of extended loops with a second layer of weakly overlapping tails. For multisticker chains, in the limit of exponentially low ϕ bulk , adsorbed polymers are well separated from each other. As l / d increases, the conformation of an individual polymer changes from a single-end-adsorbed "mushroom" to a random walk of loops. For high ϕ bulk , adsorbed polymers at small l / d are mushrooms that cover all the adsorption sites. At sufficiently large l / d , adsorbed multisticker polymers strongly overlap. We anticipate the formation of a self-similar carpet and with increasing l / d a two-layer structure with a brush of loops covered by a self-similar carpet. As l / d exceeds the

  19. Physical properties and microstructure of Ti(CN)-based cermets with different WC particle size

    International Nuclear Information System (INIS)

    Deng, Ying; Deng, Ling; Xiong, Xiang; Ye, J.W.; Li, P.P.

    2014-01-01

    Ti(CN)-based cermets with different WC particle sizes from 0.2 to 4 μm were prepared at 1450 °C with 2 MPa Air pressure. The microstructure of cermets was investigated by scanning electron microscope (SEM), X-ray diffraction (XRD), Transmission electron microscope (TEM). The results showed that all the cermets with different WC particle sizes have a typical “core–rim” structure. With the increase of WC powder sizes, the frequency and portion of Ti(C 0.7 N 0.3 ) cores and rim are somewhat decreased while the portion of white core is increased, due to the relative dissolution rate decreasing. In addition, the fracture mode of Ti(C,N) based cermets is a mixture of trans-granular (primary) and inter-granular (subordinate) fracture. The TRS (about 1850 MPa) of the cermets fluctuate slightly with the WC particle sizes from 0.2 to 1.0 μm, but decrease evidently with WC particle sizes up to 2 μm

  20. Corrosion Analysis of TiCN Coated Al-7075 Alloy for Marine Applications: A Case Study

    Science.gov (United States)

    Srinath, M. K.; Ganesha Prasad, M. S.

    2018-05-01

    Corrosion is one of the most important marine difficulties that cause long term problems, occurring in ships and submarines surrounded by a corrosive environment when coupled with chemical, temperature and stress related conditions. Corrosion of marine parts could lead to severe disasters. Coatings and heat treatment in a very effective way could be used to protect the aluminium parts against corrosion. The present case study focuses on the corrosion and microstructural properties of TiCN coatings fabricated on Al-7075 aluminium alloy substrate by using Physical Vapour Deposition technique. Corrosion properties of specimen's heat treated at 500 °C at durations of 1, 4, 8 and 12 h were tested through salt spray test. According to D-1193, ASTM standard, corrosion resistance of coated and heat treated Al-7075 samples were investigated in solution kept at 95 °F with a pH of 6.5-7.2, with 5 sections of NaCl to 95 sections of type IV water. The specimen's heat treated for 1 h showed positive corrosion resistance, while the specimens treated for longer durations had the opposite effect. The microstructures of the salt spray tested coatings were investigated by scanning electron microscope. X-ray diffraction tests were conducted on specimens to determine the atomic and molecular structure of the surface crystals and the unit cell dimensions. The corrosion mechanisms of the coated specimens under the heat treated conditions have been explored.

  1. Vibrational Mode-Specific Autodetachment and Coupling of CH2CN-

    Science.gov (United States)

    Lyle, Justin; Mabbs, Richard

    2017-06-01

    The Cyanomethyl Anion, CH_{2}CN-, and neutral radical have been studied extensively, with several findings of autodetachment about the totally symmetric transition, as well as high resolution experiments revealing symmetrically forbidden and weak vibrational features. We report photoelectron spectra using the Velocity-Mapped Imaging Technique in 1-2 \\wn increments over a range of 13460 to 15384 \\wn that has not been previously examined. These spectra include excitation of the ground state cyanomethyl anion into the direct detachment thresholds of previously reported vibrational modes for the neutral radical. Significant variations from Franck-Condon behavior were observed in the branching ratios for resolved vibrational features for excitation in the vicinity of the thresholds involving the νb{3} and νb{5} modes. These are consistent with autodetachment from rovibrational levels of a dipole bound state acting as a resonance in the detachment continuum. The autodetachment channels involve single changes in vibrational quantum number, consistent with the vibrational propensity rule but in some cases reveal relaxation to a different vibrational mode indicating coupling between the modes and/or a breakdown of the normal mode approximation.

  2. Tribological characterization of TiCN coatings deposited by two crossed laser ablation plasma beams

    Science.gov (United States)

    Camps, Enrique; Escobar-Alarcón, L.; Camps, Iván; Muhl, Stephen; Flores, Martín

    2013-03-01

    The simultaneous laser ablation of two targets (graphite and titanium) in an Ar-N2 gas mixture was carried out to deposit thin films of the ternary compound TiCN at room temperature. The base conditions used to produce the TiN without carbon were taken from our previous studies. The experimental conditions for the ablation of the carbon target were varied so that the carbon content in the films could be changed depending on the carbon ion energy. The control of the experimental conditions was carried out using a Langmuir planar probe which permitted the determination of the mean kinetic ion energy. The maximum hardness value of 35 GPa, was obtained with a carbon ion energy of about 250 eV, which corresponds to a film with 5 at% carbon content. In order to perform tribological and scratch tests, two types of substrate were used: nitrided AISI 316 stainless steel and AISI 316 stainless steel previously coated with a thin titanium layer (˜50 nm). Values of the wear rate in the range of 1.39×10-6 to 7.45×10-5 mm3 N-1 m-1, friction coefficient from 0.21 to 0.28 and adhesion from scratch test measurements up to 80 N for final critical load, were obtained.

  3. Pressure-Induced Enhanced Magnetic Anisotropy in Mn(N(CN)2)2

    Energy Technology Data Exchange (ETDEWEB)

    Quintero, P. A. [University of Florida, Gainesville; Rajan, D. [University of Florida, Gainesville; Peprah, M. K. [University of Florida, Gainesville; Brinzari, T. V. [University of Florida, Gainesville; Fishman, Randy Scott [ORNL; Talham, Daniel R. [University of Florida, Gainesville; Meisel, Mark W. [University of Florida, Gainesville

    2015-01-01

    Using DC and AC magnetometry, the pressure dependence of the magnetization of the threedimensional antiferromagnetic coordination polymer Mn(N(CN)2)2 was studied up to 12 kbar and down to 8 K. The magnetic transition temperature, Tc, increases dramatically with applied pressure (P), where a change from Tc(P = ambient) = 16:0 K to Tc(P = 12:1 kbar) = 23:5 K was observed. In addition, a marked difference in the magnetic behavior is observed above and below 7.1 kbar. Specifically, for P < 7:1 kbar, the differences between the field-cooled and zero-field-cooled (fc-zfc) magnetizations, the coercive field, and the remanent magnetization decrease with increasing pressure. However, for P > 7:1 kbar, the behavior is inverted. Additionally, for P > 8:6 kbar, minor hysteresis loops are observed. All of these effects are evidence of the increase of the superexchange interaction and the appearance of an enhanced exchange anisotropy with applied pressure.

  4. Microstructural and magnetic characterization of Co/CN films fabricated by nanolamination

    International Nuclear Information System (INIS)

    Du, J.; Wang, S.; Zhou, J.N.; Harrell, J.W.; Barnard, J.A.

    2000-01-01

    Nanolamination combined with appropriate annealing treatment has been used to produce high coercivity, heterogeneous Co-CN films with nanostructures ranging from classical granular to an interconnected network. Transmission electron microscopy and electron diffraction have been used to quantify the nanostructural evolution and resulting grain size distributions. As-deposited nanolaminates with initial layer thicknesses of 1.3 and 2.7 nm are essentially superparamagnetic. Annealing leads to coercivities of >1100 Oe. Viscosity and irreversible susceptibility measurements have been used to calculate activation volumes of ∼(18 nm) 3 , in good agreement with grain size analysis. Measurements of the time dependence of coercivity have been used to calculate the thermal stability factor, KV/kT∼480, which is independent of initial geometry. Effective first-order uniaxial anisotropy constants determined using calculated activation volumes are at maximum ∼75% of the value expected for bulk α-Co. This result is consistent with Co present in both α and β phases, as confirmed by electron diffraction

  5. Influence of culture media on the physical and chemical properties of Ag-TiCN coatings

    Science.gov (United States)

    Carvalho, I.; Escobar Galindo, R.; Henriques, M.; Palacio, C.; Carvalho, S.

    2014-08-01

    The aim of this study was to verify the possible physical and chemical changes that may occur on the surface of Ag-TiCN coatings after exposure to the culture media used in microbiological and cytotoxic assays, respectively tryptic soy broth (TSB) and Dulbecco's modified eagle's medium (DMEM). After sample immersion for 24 h in the media, analyses were performed by glow discharge optical emission spectroscopy discharge radiation (GDOES), Rutherford backscattering spectroscopy (RBS) and x-ray photoelectron spectroscopy (XPS). The results of GDOES profile, RBS and XPS spectra, of samples immersed in TSB, demonstrated the formation of a thin layer of carbon, oxygen and nitrogen that could be due to the presence of proteins in TSB. After 24 h of immersion in DMEM, the results showed the formation of a thin layer of calcium phosphates on the surface, since the coatings displayed a highly oxidized surface in which calcium and phosphorus were detected. All these results suggested that the formation of a layer on the coating surface prevented the release of silver ions in concentrations that allow antibacterial activity.

  6. Morphological evolution of prussian yellow Fe[Fe(CN){sub 6}] colloidal nanospheres

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Jianmin, E-mail: jmgu@ysu.edu.cn; Fu, Shaoyan; Jin, Cuihong; Liu, Xin; Gao, Yahui; Wu, Jingxiao; Bian, Zhenpan; Tian, Hua; Wang, Lin; Gao, Faming

    2016-07-15

    A simple hydrothermal system was developed for controllable morphologies of the Prussian yellow Fe[Fe(CN){sub 6}] nanostructures in the presence of organic additives. Hollow and solid nanospheres of the Prussian yellow materials were successfully synthesized with suitable experimental conditions. It is found that the amounts of organic additives CTAB could result in the formation of the spherical nanocrystals and the hydrolysis of phosphate in the solution could play a role in the final morphology of the products. A possible formation mechanism of the Prussian yellow nanostructures is proposed. - Graphical abstract: A hydrothermal process was developed for controllable fabrication of the Prussian yellow hollow and solid nanospheres with the employment of different phosphate. The hydrolysis of phosphate in the solution could play a role in the morphology of the Prussian yellow nanomaterials. The acid phosphate (NaH{sub 2}PO{sub 4}) could result in the formation of the solid nanoparticles. The alkalescent phosphate (Na{sub 2}HPO{sub 4}) could result in the formation of the hollow nanoparticles. Display Omitted.

  7. Surface Morphology and Hardness Analysis of TiCN Coated AA7075 Aluminium Alloy

    Science.gov (United States)

    Srinath, M. K.; Ganesha Prasad, M. S.

    2017-12-01

    Successful titanium carbonitride (TiCN) coating on AA7075 plates using the PVD technique depends upon many variables, including temperature, pressure, incident angle and energy of the reactive ions. Coated specimens have shown an increase in their surface hardness of 2.566 GPa. In this work, an attempt to further augment the surface hardness and understand its effects on the surface morphology was performed through heat treatments at 500°C for different duration of times. Specimen's heat treated at 500°C for 1 h exhibited a maximum surface hardness of 6.433 GPa, corresponding to an increase of 92.07%. The XRD results showed the presence of Al2Ti and AlTi3N and indicate the bond created between them. Unit cell lattice parameters in the XRD data are calculated using Bragg's law. The SEM images exhibit increasing crack sizes as the heat treatment time is increased. From the studies, the heat treatment duration can be optimized to 1 h, which exhibited an augmented surface hardness, as further increases in durations caused a drop in the surface hardness. The heat treatment effectively modified the surface hardness. Equations providing the relationships that temperature and time have with the reaction parameters are presented.

  8. Description of highly perturbed bands in rare earth nuclei

    International Nuclear Information System (INIS)

    Joshi, P.C.; Sood, P.C.

    1976-01-01

    Recently some highly perturbed positive parity bands have been populated in odd-mass rare earth nuclei. The energy spacings and sometimes even the spin sequences are drastically different from the usual strong coupling rotational model picture. The levels belonging to 'odd and even' I+1/2 are found to make separate groupings. The levels belonging to odd values of I+1/2 are seen to be very much favoured in comparison to the levels for which I+1/2 is even. In some cases only the favoured levels have been identified. These bands have been studied in the frame-work of rotation aligned coupling scheme in which the odd neutron in the unique parity orbital (in this case the isub(13/2) orbital) is strongly decoupled from the body fixed symmetry axis by the Coriolis force so as to make the projection of its angular momentum α on the rotation axis approximately a good quantum number. A description of the energy levels is suggested by assigning the quantum number α-j to the favoured levels and α-j-1 to the unfavoured levels. The intraband transitions of the favoured and unfavoured bands are examined in comparison with those in the adjacent ground state bands in even-even nuclei. (author)

  9. Identical and shifted identical bands

    International Nuclear Information System (INIS)

    Dodder, R.S; Jones, E.F.; Hamilton, J.H.

    1997-01-01

    Spontaneous fission of 252 Cm was studied with 72 large Compton suppressed Ge detectors in Gamma sphere. New isotopes 160 Sm and 162 Gd were identified. Through X-ray-γ and γ-γ-γ) coincidence measurements, level energies were established to spins 14 + to 20 + in 152 , 154 156 60 Nd 92 94 96 , 156 , 158 , 160 62 Sm 94 , 96 , 98 , and 160 , 162 64 Gd 96 , 98 . These nuclei exhibit a remarkable variety of identical bands and bands where the energies and moments of inertia are shifted by the same constant amount for every spin state from 2 + to 12 + for various combinations of nuclei differing by 2n, 4n, 2p, 4p, and α

  10. Table of superdeformed nuclear bands and fission isomers

    International Nuclear Information System (INIS)

    Firestone, R.B.; Singh, B.

    1994-06-01

    A minimum in the second potential well of deformed nuclei was predicted and the associated shell gaps are illustrated in the harmonic oscillator potential shell energy surface calculations shown in this report. A strong superdeformed minimum in 152 Dy was predicted for β 2 -0.65. Subsequently, a discrete set of γ-ray transitions in 152 DY was observed and, assigned to the predicted superdeformed band. Extensive research at several laboratories has since focused on searching for other mass regions of large deformation. A new generation of γ-ray detector arrays is already producing a wealth of information about the mechanisms for feeding and deexciting superdeformed bands. These bands have been found in three distinct regions near A=l30, 150, and 190. This research extends upon previous work in the actinide region near A=240 where fission isomers were identified and also associated with the second potential well. Quadrupole moment measurements for selected cases in each mass region are consistent with assigning the bands to excitations in the second local minimum. As part of our committment to maintain nuclear structure data as current as possible in the Evaluated Nuclear Structure Reference File (ENSDF) and the Table of Isotopes, we have updated the information on superdeformed nuclear bands. As of April 1994, we have complied data from 86 superdeformed bands and 46 fission isomers identified in 73 nuclides for this report. For each nuclide there is a complete level table listing both normal and superdeformed band assignments; level energy, spin, parity, half-life, magneto moments, decay branchings; and the energies, final levels, relative intensities, multipolarities, and mixing ratios for transitions deexciting each level. Mass excess, decay energies, and proton and neutron separation energies are also provided from the evaluation of Audi and Wapstra

  11. Table of superdeformed nuclear bands and fission isomers

    Energy Technology Data Exchange (ETDEWEB)

    Firestone, R.B. [Lawrence Berkeley Lab., CA (United States); Singh, B. [McMaster Univ., Hamilton, ON (Canada)

    1994-06-01

    A minimum in the second potential well of deformed nuclei was predicted and the associated shell gaps are illustrated in the harmonic oscillator potential shell energy surface calculations shown in this report. A strong superdeformed minimum in {sup 152}Dy was predicted for {beta}{sub 2}-0.65. Subsequently, a discrete set of {gamma}-ray transitions in {sup 152}DY was observed and, assigned to the predicted superdeformed band. Extensive research at several laboratories has since focused on searching for other mass regions of large deformation. A new generation of {gamma}-ray detector arrays is already producing a wealth of information about the mechanisms for feeding and deexciting superdeformed bands. These bands have been found in three distinct regions near A=l30, 150, and 190. This research extends upon previous work in the actinide region near A=240 where fission isomers were identified and also associated with the second potential well. Quadrupole moment measurements for selected cases in each mass region are consistent with assigning the bands to excitations in the second local minimum. As part of our committment to maintain nuclear structure data as current as possible in the Evaluated Nuclear Structure Reference File (ENSDF) and the Table of Isotopes, we have updated the information on superdeformed nuclear bands. As of April 1994, we have complied data from 86 superdeformed bands and 46 fission isomers identified in 73 nuclides for this report. For each nuclide there is a complete level table listing both normal and superdeformed band assignments; level energy, spin, parity, half-life, magneto moments, decay branchings; and the energies, final levels, relative intensities, multipolarities, and mixing ratios for transitions deexciting each level. Mass excess, decay energies, and proton and neutron separation energies are also provided from the evaluation of Audi and Wapstra.

  12. NCenter wide band neutrino beam

    International Nuclear Information System (INIS)

    Stutte, L.G.

    1985-01-01

    This memo describes the physical properties of the currently operating N-Center wide band neutrino beam---commonly called the triplet train, following a past tradition of a triplet lens configuration. In reality, in order to gain a larger momentum acceptance and to minimize the angular divergence of the beam, a quadruplet beam (4 lenses) employing point-to-parallel optics at a central momentum of 300 GeV was built. 6 refs., 13 figs., 1 tab

  13. Sub-band-gap absorption in Ga2O3

    Science.gov (United States)

    Peelaers, Hartwin; Van de Walle, Chris G.

    2017-10-01

    β-Ga2O3 is a transparent conducting oxide that, due to its large bandgap of 4.8 eV, exhibits transparency into the UV. However, the free carriers that enable the conductivity can absorb light. We study the effect of free carriers on the properties of Ga2O3 using hybrid density functional theory. The presence of free carriers leads to sub-band-gap absorption and a Burstein-Moss shift in the onset of absorption. We find that for a concentration of 1020 carriers, the Fermi level is located 0.23 eV above the conduction-band minimum. This leads to an increase in the electron effective mass from 0.27-0.28 me to 0.35-0.37 me and a sub-band-gap absorption band with a peak value of 0.6 × 103 cm-1 at 3.37 eV for light polarized along the x or z direction. Both across-the-gap and free-carrier absorption depend strongly on the polarization of the incoming light. We also provide parametrizations of the conduction-band shape and the effective mass as a function of the Fermi level.

  14. Shear bands as growing instabilities in viscoanelastic media with memory

    Directory of Open Access Journals (Sweden)

    Marina Dolfin

    2013-09-01

    Full Text Available In this paper we investigate the critical conditions under which a small perturbation in an homogeneous continuum can possibly grows into a shear band instability. In particular, we analyze from a thermodynamical viewpoint the phenomenon of shear bands in viscoanelastic media with memory. It is emphasized, in the scientific literature, that the specific adopted rheology strongly affects the results so that a special attention has to be paid, also for engineering purposes, to the accuracy of the rheological model. Several well-known rheological model (for instance the so called Maxwell or Jeffreys media are particular cases of the general model we adopt in the paper to analyze shear bands. Instability conditions, giving rise to shear bands formation, are obtained by introducing small perturbations around an homogeneous deformation into the system of differential equations governing the problem of homogeneous deformations in the considered continuous medium; as a result a non-homogeneous linear dynamical system is obtained whose stability is analyzed. A research perspective in view of a possible comparison with experimental results is proposed; in particular the simple methodology proposed in the paper should be applied in view of using the phenomenon of the initiation of shear bands to calculate the thermomechanical coefficients of real materials.

  15. In situ electrochemical SFG/DFG study of CN- and nitrile adsorption at Au from 1-butyl-1-methyl-pyrrolidinium bis(trifluoromethylsulfonyl) amide ionic liquid([BMP][TFSA]) containing 4-{2-[1-(2-cyanoethyl)-1,2,3,4-tetrahydroquinolin-6-yl]diazenyl} benzonitrile (CTDB) and K[Au(CN)₂].

    Science.gov (United States)

    Bozzini, Benedetto; Busson, Bertrand; Gayral, Audrey; Humbert, Christophe; Mele, Claudio; Six, Catherine; Tadjeddine, Abderrahmane

    2012-06-25

    In this paper we report an in situ electrochemical Sum-/Difference Frequency Generation (SFG/DFG) spectroscopy investigation of the adsorption of nitrile and CN⁻ from the ionic liquid 1-butyl-1-methyl-pyrrolidinium bis(trifluoromethylsulfonyl) amide ([BMP][TFSA]) containing 4-{2-[1-(2-cyanoethyl)-1,2,3,4-tetrahydroquinolin-6-yl]-diazenyl}benzonitrile (CTDB) at Au electrodes in the absence and in the presence of the Au-electrodeposition process from K[Au(CN)₂]. The adsorption of nitrile and its coadsorption with CN⁻ resulting either from the cathodic decomposition of the dye or from ligand release from the Au(I) cyanocomplex yield potential-dependent single or double SFG bands in the range 2,125-2,140 cm⁻¹, exhibiting Stark tuning values of ca. 3 and 1 cm⁻¹ V⁻¹ in the absence and presence of electrodeposition, respectively. The low Stark tuning found during electrodeposition correlates with the cathodic inhibiting effect of CTDB, giving rise to its levelling properties. The essential insensitivity of the other DFG parameters to the electrodeposition process is due to the growth of smooth Au.

  16. [Gastric band erosion: Alternative management].

    Science.gov (United States)

    Echaverry-Navarrete, Denis José; Maldonado-Vázquez, Angélica; Cortes-Romano, Pablo; Cabrera-Jardines, Ricardo; Mondragón-Pinzón, Erwin Eduardo; Castillo-González, Federico Armando

    2015-01-01

    Obesity is a public health problem, for which the prevalence has increased worldwide at an alarming rate, affecting 1.7 billion people in the world. To describe the technique employed in incomplete penetration of gastric band where endoscopic management and/or primary closure is not feasible. Laparoscopic removal of gastric band was performed in five patients with incomplete penetrance using Foley catheterization in the perforation site that could lead to the development of a gastro-cutaneous fistula. The cases presented include a leak that required surgical lavage with satisfactory outcome, and one patient developed stenosis 3 years after surgical management, which was resolved endoscopically. In all cases, the penetration site closed spontaneously. Gastric band erosion has been reported in 3.4% of cases. The reason for inserting a catheter is to create a controlled gastro-cutaneous fistula, allowing spontaneous closure. Various techniques have been described: the totally endoscopic, hybrid techniques (endoscopic/laparoscopic) and completely laparoscopic. A technique is described here that is useful and successful in cases where the above-described treatments are not viable. Copyright © 2015. Published by Masson Doyma México S.A.

  17. Synthesis of (Cr,V){sub 2}(C,N) solid solution powders by thermal processing precursors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Anrui [School of Materials Science & Engineering, Sichuan University, Chengdu, 610065 (China); Liu, Ying [School of Materials Science & Engineering, Sichuan University, Chengdu, 610065 (China); Key Laboratory of Advanced Special Material & Technology, Ministry of Education, Chengdu, 610065 (China); Ma, Shiqing; Qiu, Yuchong; Rong, Pengcheng; Ye, Jinwen [School of Materials Science & Engineering, Sichuan University, Chengdu, 610065 (China)

    2017-06-01

    The single-phase (Cr,V){sub 2}(C,N) solid solution powders were fabricated via carbothermal reduction-nitridation (CRN) processing technique. The effects of heat treatment temperature, nitrogen pressure and carbon proportion were experimentally studied in detail by X-ray Diffraction (XRD), Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM) and thermal analysis. The chemical transformations of vanadium and chromium compounds were as follows: precursors → V{sub 2}O{sub 3}, Cr{sub 2}O{sub 3} → Cr{sub 3}C{sub 2}, Cr{sub 2}O{sub 3}, (Cr,V){sub 2}(C,N) → (Cr,V){sub 2}(C,N). When the heat-treated temperature was below 1200 °C, chromium oxides didn’t completely react. However, higher temperature ∼1300 °C could not only lead to the segregation of some nitrides and carbon black, but also to the occurrence of fiber-bridged particles. The system nitrogen pressure over 0.03 MPa would cause a subtle transformation of (Cr,V){sub 2}(C,N) to VCrN{sub 2}. When the carbon proportion was below 15 wt%, the oxides could not be completely reduced, while when the carbon proportion was above 15.5 wt%, some undesired carbides, like Cr{sub 23}C{sub 6} and Cr{sub 3}C{sub 2}, would form. Ultimately, the homogeneously distributed pure-phase (Cr,V){sub 2}(C,N) spherical particles with the average size of ∼1.5 μm were obtained at the optimal conditions of the treatment of precursors at 1200 °C for 1 h with the nitrogen pressure of 0.03 MPa and carbon content of 15.5 wt%. The chemical composition of the solid solution with the optimal process could be drawn as (Cr{sub 0.85}V{sub 0.15}){sub 2}(C{sub 0.57}N{sub 0.43}). Thermal processing precursors method shows the advantages of lower synthesis temperature, shorter period and finer particles when comparing with the conventional preparations. - Highlights: • Single phase of (Cr,V){sub 2}(C,N) powders were synthesized for the first time. • Precursors were used to prepared the powders by carbothermal

  18. Strong growth for Queensland mining

    Energy Technology Data Exchange (ETDEWEB)

    1990-10-01

    The Queensland mining industry experienced strong growth during 1989-90 as shown in the latest statistics released by the Department of Resource Industries. The total value of Queensland mineral and energy production rose to a new record of $5.1 billion, an increase of 16.5% on 1988-89 production. A major contributing factor was a 20.9 percent increase in the value of coal production. While the quantity of coal produced rose only 1.1 percent, the substantial increase in the value of coal production is attributable to higher coal prices negotiated for export contracts. In Australian dollar terms coal, gold, lead, zinc and crude oil on average experienced higher international prices than in the previous year. Only copper and silver prices declined. 3 tabs.

  19. Strong moduli stabilization and phenomenology

    CERN Document Server

    Dudas, Emilian; Mambrini, Yann; Mustafayev, Azar; Olive, Keith A

    2013-01-01

    We describe the resulting phenomenology of string theory/supergravity models with strong moduli stabilization. The KL model with F-term uplifting, is one such example. Models of this type predict universal scalar masses equal to the gravitino mass. In contrast, A-terms receive highly suppressed gravity mediated contributions. Under certain conditions, the same conclusion is valid for gaugino masses, which like A-terms, are then determined by anomalies. In such models, we are forced to relatively large gravitino masses (30-1000 TeV). We compute the low energy spectrum as a function of m_{3/2}. We see that the Higgs masses naturally takes values between 125-130 GeV. The lower limit is obtained from the requirement of chargino masses greater than 104 GeV, while the upper limit is determined by the relic density of dark matter (wino-like).

  20. Strongly interacting W's and Z's

    International Nuclear Information System (INIS)

    Gaillard, M.K.

    1984-01-01

    The study focussed primarily on the dynamics of a strongly interacting W, Z(SIW) sector, with the aim of sharpening predictions for total W, Z yield and W, Z multiplicities expected from WW fusion for various scenarios. Specific issues raised in the context of the general problem of modeling SIW included the specificity of the technicolor (or, equivalently, QCD) model, whether or not a composite scalar model can be evaded, and whether the standard model necessarily implies an I = J = O state (≅ Higgs particle) that is relatively ''light'' (M ≤ hundreds of TeV). The consensus on the last issue was that existing arguments are inconclusive. While the author shall briefly address compositeness and alternatives to the technicolor model, quantitative estimates will be of necessity based on technicolor or an extrapolation of pion data