Sample records for h-3 i-129 c-14

  1. AMS measurements of 14C and 129I in seawater around radioactive waste dump sites

    NASA Astrophysics Data System (ADS)

    Povinec, P. P.; Oregioni, B.; Jull, A. J. T.; Kieser, W. E.; Zhao, X.-L.

    2000-10-01

    According to a recent IAEA compilation of inventories of radioactive wastes dumped in the world ocean, a total of 85 PBq of radioactive wastes were dumped, in the Atlantic (45 PBq), the Pacific (1.4 PBq) and the Arctic (38 PBq) Oceans and their marginal seas between 1946 and 1993, mostly in the form of low-level wastes. 3H, and 14C formed an important part of the beta-activity of these dumped wastes. Because of its long half-life, 14C will be the main constituent in possible leakages from the wastes in the future. On the other hand, 14C and 129I are important radioactive tracers which have been artificially introduced into the oceans. Small amounts of 14C and 129I can be easily measured by accelerator mass spectrometry (AMS) on mg-size samples of carbon and iodine extracted from 500 ml seawater samples. The high analytical sensitivity enables one therefore to find even trace amounts of 14C and 129I which could be released from radioactive wastes, and to compare the measured levels with the global distribution of these radionuclides. The IAEAs Marine Environment Laboratory (IAEA-MEL) has been engaged in an assessment program related to radioactive waste dumping in the oceans since 1992 and has participated in several expeditions to the Atlantic, Arctic, Indian and Pacific Oceans to sample seawater, biota and sediment for radiological assessment studies. In the present paper, we report on methods of 14C and 129I measurements in seawater by AMS and present data on the NE Atlantic, the Arctic and the NW Pacific Ocean dumping sites. A small increase of 14C was observed at the NE Atlantic dumping site.

  2. Isolation of 1,4-Li(2)-C(6)H(4) and its reaction with [(Ph(3)P)AuCl].

    PubMed

    Flower, Kevin R; McGown, A T; Miles, Philip J; Pritchard, Robin G; Warren, John E

    2010-04-14

    The difficulty in generating 1,4-Li2-C6H4 utilising the lithium halogen exchange reaction on 1,4-Br2-C6H4, 1,4-I2-C6H4 and 1-Br-4-I-C6H4 is revisited and only on treatment of 1,4-I2-C6H4 with 2 molar equivalents of n-BuLi can 1,4-Li2-C6H4 1 be isolated in excellent yield. Treatment of 1 with two equivalents of [ClAu(PPh3)] gives [1,4-(Ph3PAu)2-C6H4] 2a in excellent yield. Subsequent treatment of 2a with 2.5 molar equivalents of PPh2Me, PPhMe2 or PMe3 affords the PPh3 substituted compounds [1,4-(LAu)2-C6H4] (L = PPh2Me 2b, PPhMe2 2c, PMe3 2d) in essentially quantitative yields. On treatment of 1,4-Br2-C6H4 or 1-Br-4-I-C6H4 with 2 molar equivalents of n-BuLi only mono-lithiation takes place to give 1-Br-4-Li-C6H4 3 as shown through the isolation of essentially 1:1 molar equivalents of Ph2PC6H4-4-Br and Ph2PBu on treatment with 2 molar equivalents of ClPPh2. Treatment of 3, prepared by lithium/iodine exchange on 1-Br-4-I-C6H4, with [ClAu(PPh3)] affords [(Ph3P)Au(C6H4-4-Br)] 4 as expected and in addition [(Ph3P)Au(n-Bu)(C6H4-4-Br)2] 5, indicating the straightforward chloride/aryl exchange at gold may proceed in competition with oxidative addition of the n-BuI, generated in the initial lithium/iodine exchange reaction, to some aurate complex Li[Au(C6H4-4-Br)2] 6 formed in situ followed by reductive elimination of Br-C6H4-4-n-Bu in a manner that mimics lithium diorganocuprate chemistry. All of the gold-containing compounds have been spectroscopically characterised by 1H and 31P-{1H} NMR and in addition compounds 2a-d and 5 by single crystal X-ray diffraction studies. The solid state structures observed for 2a-d are dictated by non-conventional hydrogen bonding and the packing requirements of the phosphine ligands. For 2a and 2b there is no close Au...Au approach, however for 2c and 2d the reduction in the number of phenyl rings allows the formation of Au...Au contacts. For 2c and 2d the extended structures appear to be helical chains with Au...Au contact parameters of 3

  3. Reactions of the linear tetranuclear complex Ru sub 4 (CO) sub 10 (CH sub 3 C double bond C(H)C(H) double bond N-i-Pr) sub 2 with oxidizing reagents. Syntheses of halide-bridged (Ru(CO) sub 2 X(CH sub 3 C double bond C(H)C(H) double bond N-i-Pr)) sub 2 and fac-Ru(CO) sub 3 X(CH sub 3 C double bond C(H)C(H) double bond N-i-Pr)

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

    Mul, W.P.; Elsevier, C.J.; van Leijen, M.

    1991-01-01

    The linear tetranuclear complex Ru{sub 4}(CO){sub 10}(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr){sub 2} (1), containing two {eta}{sup 5}-azaruthenacyclopentadienyl systems, reacts with oxidizing reagents (I{sub 2}, Br{sub 2}, NBS, CCl{sub 4}) at elevated temperatures (40-90C) in heptane or benzene to give the new dimeric halide-bridged organoruthenium(II) complexes (Ru(CO){sub 2}X(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr)){sub 2} (X = I (3a), X = Br (3b), Cl (3c); yield 30-80%) together with (Ru(CO){sub 3}X{sub 2}){sub 2}. The reactions of 1 with CX{sub 4} (X = I, Br, Cl) are accelerated by CO, probably because Ru{sub 4}(CO){sub 12}(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr){sub 2} (5), which contains two unbridged metal-metal bonds,more » is formed prior to oxidation. The halide-bridged dimers 3a-c are obtained as mixtures of four isomers, the configurations of which are discussed. Splitting of the halide bridges takes place when a solution of 3a-c is saturated with CO, whereby mononuclear fac-Ru(CO){sub 3}X(CH{sub 3}C{double bond}C(H)C(H){double bond}N-i-Pr) (4a-c) is obtained. This process is reversible; ie., passing a stream of nitrogen through a solution of 4a-c or removal of the solvent under vacuum causes the reverse reaction with reformation of 3a-c. Compounds 3a-c and 4a-c have been characterized by IR (3, 4), FD mass (3), {sup 1}H (3, 4), and {sup 13}C{l brace}H{r brace} NMR (4) spectroscopy and satisfactory elemental analyses have been obtained for 3a-c. Compounds 3 and 4 are suitable precursors for the preparation of new homo- and heteronuclear transition-metal complexes.« less

  4. Improved approach for routine monitoring of 129I activity and 129I/127I atom ratio in environmental samples using TMAH extraction and ICP-MS/MS.

    PubMed

    Yang, Guosheng; Tazoe, Hirofumi; Yamada, Masatoshi

    2018-05-30

    To reconstruct 131 I deposition and identify the source of radioiodine due to the Fukushima Daiichi Nuclear Power Plant (FDNPP) accident, 129 I activity and 129 I/ 127 I atom ratio should be obtained by preparing and analyzing large numbers of samples economically. In this study, great efforts were made to realize mild TMAH (tetramethyl ammonium hydroxide) extraction of environmental samples at 90 °C to obtain solutions suitable for the following triple-quadrupole inductively coupled plasma-mass spectrometry (ICP-QQQ) MS/MS mode analysis. After releasing iodine from organic matter in the TMAH extraction solution via K 2 S 2 O 8 oxidation, organic matter was removed effectively by solvent extraction and back-extraction to avoid a serious matrix effect during ICP-QQQ analysis. At the same time, interfering elements, especially, Mo, Cd, and In were also removed effectively, to avoid their undesirable interferences during mass spectrometric analysis. In addition, 0.01% (NH 4 ) 2 SO 3 was selected to introduce I - into ICP-QQQ to ensure there was no memory effect and a stable signal was gotten. Subsequently, ICP-QQQ MS/MS mode was applied to further eliminate polyatomic interferences ( 127 I(H 2 and D) + , 97 MoO 2 + , 113 InO + , and 113 CdO + ) and isobaric interference from 129 Xe + . Finally, the developed method was successfully applied to measure 129 I/ 127 I atom ratios ((2.61-27.0) × 10 -7 ) and 129 I activities (3.51-11.4 mBq kg -1 ) in soil samples. The developed method allows a greater number of ordinary laboratories to participate in the field of radioiodine analysis. Copyright © 2018 Elsevier B.V. All rights reserved.

  5. Kinetics of the R + NO2 reactions (R = i-C3H7, n-C3H7, s-C4H9, and t-C4H9) in the temperature range 201-489 K.

    PubMed

    Rissanen, Matti P; Arppe, Suula L; Eskola, Arkke J; Tammi, Matti M; Timonen, Raimo S

    2010-04-15

    The bimolecular rate coefficients of four alkyl radical reactions with NO(2) have been measured in direct time-resolved experiments. Reactions were studied under pseudo-first-order conditions in a temperature-controlled tubular flow reactor coupled to a laser photolysis/photoionization mass spectrometer (LP-PIMS). The measured reaction rate coefficients are independent of helium bath gas pressure within the experimental ranges covered and exhibit negative temperature dependence. For i-C(3)H(7) + NO(2) and t-C(4)H(9) + NO(2) reactions, the dependence of ordinate (logarithm of reaction rate coefficients) on abscissa (1/T or log(T)) was nonlinear. The obtained results (in cm(3) s(-1)) can be expressed by the following equations: k(n-C(3)H(7) + NO(2)) = ((4.34 +/- 0.08) x 10(-11)) (T/300 K)(-0.14+/-0.08) (203-473 K, 1-7 Torr), k(i-C(3)H(7) + NO(2)) = ((3.66 +/- 2.54) x 10(-12)) exp(656 +/- 201 K/T)(T/300 K)(1.26+/-0.68) (220-489 K, 1-11 Torr), k(s-C(4)H(9) + NO(2)) = ((4.99 +/- 0.16) x 10(-11))(T/300 K)(-1.74+/-0.12) (241-485 K, 2 - 12 Torr) and k(t-C(4)H(9) + NO(2)) = ((8.64 +/- 4.61) x 10(-12)) exp(413 +/- 154 K/T)(T/300 K)(0.51+/-0.55) (201-480 K, 2-11 Torr), where the uncertainties shown refer only to the 1 standard deviations obtained from the fitting procedure. The estimated overall uncertainty in the determined bimolecular rate coefficients is about +/-20%.

  6. 14 CFR 129.25 - Airplane security.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Airplane security. 129.25 Section 129.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.25 Airplane...

  7. 14 CFR 129.25 - Airplane security.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Airplane security. 129.25 Section 129.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.25 Airplane...

  8. 14 CFR 129.25 - Airplane security.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Airplane security. 129.25 Section 129.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.25 Airplane...

  9. 14 CFR 129.25 - Airplane security.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Airplane security. 129.25 Section 129.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.25 Airplane...

  10. 14 CFR 129.25 - Airplane security.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Airplane security. 129.25 Section 129.25 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIR CARRIERS... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.25 Airplane...

  11. 14 CFR 129.29 - Smoking prohibitions.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Smoking prohibitions. 129.29 Section 129.29... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.29 Smoking prohibitions. (a) No person may smoke and no operator may permit smoking in any aircraft lavatory. (b) Unless...

  12. 14 CFR 129.29 - Smoking prohibitions.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Smoking prohibitions. 129.29 Section 129.29... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.29 Smoking prohibitions. (a) No person may smoke and no operator may permit smoking in any aircraft lavatory. (b) Unless...

  13. 14 CFR 129.29 - Smoking prohibitions.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Smoking prohibitions. 129.29 Section 129.29... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.29 Smoking prohibitions. (a) No person may smoke and no operator may permit smoking in any aircraft lavatory. (b) Unless...

  14. 14 CFR 129.29 - Smoking prohibitions.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Smoking prohibitions. 129.29 Section 129.29... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.29 Smoking prohibitions. (a) No person may smoke and no operator may permit smoking in any aircraft lavatory. (b) Unless...

  15. 14 CFR 129.29 - Smoking prohibitions.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Smoking prohibitions. 129.29 Section 129.29... AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.29 Smoking prohibitions. (a) No person may smoke and no operator may permit smoking in any aircraft lavatory. (b) Unless...

  16. Live 129I-129Xe dating

    NASA Technical Reports Server (NTRS)

    Marti, K.

    1986-01-01

    A technique of cosmic ray exposure age dating using cosmic ray produced I-129 and Xe-129 components is discussed. The live I-129 - Xe-129 method provides an ideal monitor for cosmic ray flux variations on the 10(7)y - 10(8)y time-scale. It is based on low-energy neutron reactions on Te, and these data, when coupled to those from other methods, may facilitate the detection of complex exposure histories.

  17. (C{H3})3N\\cdot\\cdot\\cdotAgI AND H3N\\cdot\\cdot\\cdotAgI STUDIED BY BROADBAND ROTATIONAL SPECTROSCOPY AND AB INITIO CALCULATIONS

    NASA Astrophysics Data System (ADS)

    Bittner, Dror M.; Zaleski, Daniel P.; Stephens, Susanna L.; Walker, Nick; Legon, Anthony

    2015-06-01

    The pure rotational spectra of 8 isotopologues of H3N\\cdot\\cdot\\cdotAgI and 6 isotopologues of (C{H3})3N\\cdot\\cdot\\cdotAgI were measured in a chirped pulse Fourier-transform microwave spectrometer. The complexes were synthesized in a molecular beam from a gas sample containing H3N or (C{H3})3N and CF3I precursors diluted in argon. Laser ablation was used to introduce silver atoms to the gas phase. The rotational constant B0, centrifugal distortion constants DJ and DJK, and the nuclear quadrupole coupling constant χaa(I) have been determined for (C{H3})314/15N\\cdot\\cdot\\cdot107/109AgI, (C{D3})3N\\cdot\\cdot\\cdot107/109AgI, H314/15N\\cdot\\cdot\\cdot107/109AgI and D3N\\cdot\\cdot\\cdot107/109AgI by fitting the measured transitions to a symmetric top Hamiltonian. The spectroscopic constants (B0+ C0), ΔJ and χaa(I) have been determined for D2HN\\cdot\\cdot\\cdot107/109AgI through fits that employed a Hamiltonian appropriate for a very near prolate asymmetric rotor. Partial effective (r0) and substitution (rs) structures have been determined.

  18. 14 CFR 129.15 - Flight crewmember certificates.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flight crewmember certificates. 129.15 Section 129.15 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... § 129.15 Flight crewmember certificates. No person may act as a flight crewmember unless he holds a...

  19. Synthetic and Spectroscopic Studies on N-(i,j-Disubstituted Phenyl)-4- Substituted Benzenesulphonamides, 4-X'C6H4SO2NH(i,j-X2C6H3), where X' = H, CH3, C2H5, F, Cl or Br; i, j = 2, 3; 2, 4; 2, 5; 2, 6 or 3, 4; and X = CH3 or Cl

    NASA Astrophysics Data System (ADS)

    Shetty, Mahesha; Gowda, B. Thimme

    2005-02-01

    Fifty four N-(i,j-disubstituted phenyl)-4-substituted benzenesulphonamides of the general formula 4-X'C6H4SO2NH(i,j-X2C6H3), where X' = H, CH3, C2H5, F, Cl or Br; i,j = 2,3; 2,4; 2,5; 2,6 or 3, 4; and X = CH3 or Cl, are prepared and characterized and their infrared, 1H and 13C NMR spectra in solution are studied. The N-H stretching vibrations νN-H absorb in the range 3305 - 3205 cm-1, while the asymmetric and symmetric SO2 vibrations vary in the ranges 1377 - 1307 cm-1 and 1184 - 1128 cm-1, respectively. The N-(i,j-disubstituted phenyl)-4-substituted benzenesulphonamides show C-S, S-N and C-N stretching vibrations in the ranges 844 - 800 cm-1, 945 - 891 cm-1 and 1309 - 1170 cm-1, respectively. The compounds do not exhibit particular trends in the variation of these frequencies on substitution either at ortho or meta positions with either a methyl group or Cl. The observed 1H and 13C chemical shifts of are assigned to protons and carbon atoms of the two benzene rings. Incremental shifts of the ring protons and carbon atoms due to -SO2NH(i,j-X2C6H3) groups in C6H5SO2NH(i,j-X2C6H3) and 4-X'C6H4SO2NH- groups in 4-X'C6H4SO2NH(C6H*) are computed and employed to calculate the chemical shifts of the ring protons and carbon atoms in the substituted compounds 4-X'C6H4SO2NH(i,j-X2C6H3). The different methods of calculation lead to almost the same values in most cases and agree well with the observed chemical shifts, indicating the validity of the principle of additivity of the substituent effects with chemical shifts in these compounds.

  20. 14 CFR 129.28 - Flightdeck security.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Flightdeck security. 129.28 Section 129.28... Flightdeck security. (a) After August 20, 2002, except for a newly manufactured airplane on a non-revenue...; or the operator must implement a security program approved by the Transportation Security...

  1. 14 CFR 129.28 - Flightdeck security.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Flightdeck security. 129.28 Section 129.28... Flightdeck security. (a) After August 20, 2002, except for a newly manufactured airplane on a non-revenue...; or the operator must implement a security program approved by the Transportation Security...

  2. 14 CFR 129.28 - Flightdeck security.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Flightdeck security. 129.28 Section 129.28... Flightdeck security. (a) After August 20, 2002, except for a newly manufactured airplane on a non-revenue...; or the operator must implement a security program approved by the Transportation Security...

  3. C-14/I-29 Preservation and Hold Time Survey

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

    Kitchen, S.

    2015-04-08

    Preservation and hold time of radionuclides must account for both nuclear half-lives and nonnuclear loss mechanisms, but variations in the latter are often neglected. Metals-based defaults are inappropriate for long-lived non-metals C-14 and I-129, which are vulnerable to chemical and biological volatilization. Non-acidification is already widely practiced for them. Recommended addition measures from radiological and chemical literature include glass containers where possible, water filtration where possible, headspace minimization, light shielding, cold (4°C) storage and unfiltered water hold time of 28 days. Soil hold time may need to be shortened when water-logged, excessively sandy, or still adjusting to significant new contamination.

  4. Crystal structure, quantum mechanical investigation, IR and NMR spectroscopy of two new organic perchlorates: (C6H18N3)·(ClO4)3H2O (I) and (C9H11N2)·ClO4(II)

    NASA Astrophysics Data System (ADS)

    Bayar, I.; Khedhiri, L.; Soudani, S.; Lefebvre, F.; Ferretti, V.; Ben Nasr, C.

    2018-06-01

    The reaction of perchloric acid with 1-(2-aminoethyl)piperazine or 5,6-dimethyl-benzimidazole results in the formation of 1-(2-amonioethyl)piperazine-1,4-dium triperchlorate hydrate (C6H18N3)·(ClO4)3·H2O (I) or 5,6-dimethyl-benzylimidazolium perchlorate (C9H11N2)·ClO4(II). Both compounds were fully structurally characterized including single crystal X-ray diffraction analysis. Compound (I) crystallizes in the centrosymmetric triclinic space group P 1 bar with the lattice parameters a = 7.455 (2), b = 10.462 (2), c = 10.824 (2) Å, α = 80.832 (2), β = 88.243 (2), γ = 88.160 (2) °, Z = 2 and V = 832.77 (3) Å3. Compound (II) has been found to belong to the P21/c space group of the monoclinic system, with a = 7.590 (3), b = 9.266 (3), c = 16.503 (6) Å, β = 107.38 (2) °, V = 1107.69 (7) Å3 and Z = 4. The structures of (I) and (II) consist of slightly distorted [ClO4]- tetrahedra anions and 1-(2-amonioethyl)piperazine-1,4-dium trication (I) or 5,6-dimethyl-benzylimidazolium cations (II) and additionally a lattice water in (I). The crystal structures of (I) and (II) exhibit complex three-dimensional networks of H-bonds connecting all their components. In the atomic arrangement of (I), the ClO4- anions form corrugated chains, while in (II) the atomic arrangement exhibits wide pseudo-hexagonal channels of ClO4 tetrahedra including the organic entities. The lattice water serves as a link between pairs of cations and pairs of anions via several Osbnd H⋯O and N-H⋯O interactions in compound (I). The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid-state 13C, 35Cl and 15N NMR spectroscopy. DFT calculations allowed the attribution of the IR and NMR bands. Intermolecular interactions were investigated by Hirshfeld surfaces. Electronic properties such as HOMO and LUMO energies were derived.

  5. Modelling disorder in 3,3' -dimethoxybensil, C[subscript 16]H[subscript 14]O[subscript 4

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

    Goossens, Darren J.; Welberry, T.Richard; Heerdegen, Aidan P.

    2008-06-18

    This work is part of an extended study of benzil (C{sub 14}H{sub 10}O{sub 2}) and some of its derivatives which aims to understand the role of molecular flexibility in crystal packing and polymorphism. Significant steps have been made in modelling the structured thermal diffuse scattering from 3,3'-dimethoxybenzil, C{sub 16}H{sub 1}4O{sub 4}. It appears that the structure can be considered as a stack of layers of molecules in which interactions are strongest within the layers. The layers interact weakly along the a direction but more strongly along c, so shearing of the planes relative to each other is energetically likely. Themore » molecule must be treated as flexible for a good model to be found.« less

  6. The radioactivity estimation of 14C and 3H in graphite waste samples of the KRR-2.

    PubMed

    Reyoung Kim, Hee

    2013-09-01

    The radioactivity of (14)C and (3)H in graphite samples from the dismantled Korea Research Reactor-2 (the KRR-2) site was analyzed by high-temperature oxidation and liquid scintillation counting, and the graphite waste was suggested to be disposed of as a low-level radioactive waste. The graphite samples were oxidized at a high temperature of 800 °C, and their counting rates were measured by using a liquid scintillation counter (LSC). The combustion ratio of the graphite was about 99% on the sample with a maximum weight of 1g. The recoveries from the combustion furnace were around 100% and 90% in (14)C and (3)H, respectively. The minimum detectable activity was 0.04-0.05 Bq/g for the (14)C and 0.13-0.15 Bq/g for the (3)H at the same background counting time. The activity of (14)C was higher than that of (3)H over all samples with the activity ratios of the (14)C to (3)H, (14)C/(3)H, being between 2.8 and 25. The dose calculation was carried out from its radioactivity analysis results. The dose estimation gave a higher annual dose than the domestic legal limit for a clearance. It was thought that the sampled graphite waste from the dismantled research reactor was not available for reuse or recycling and should be monitored as low-level radioactive waste. Copyright © 2013 Elsevier Ltd. All rights reserved.

  7. 127I and 129I/127I isotopic ratio in marine alga Fucus virsoides from the North Adriatic Sea.

    PubMed

    Osterc, Andrej; Stibilj, Vekoslava

    2008-04-01

    The only stable iodine isotope is 127I and the natural 129I/127I ratio in the biosphere has increased from 10(-15)-10(-14) to 10(-10)-10(-9), mainly due to emissions from nuclear fuel reprocessing plants. In Europe they are located at La Hague (France) and Sellafield (England), where the ratio of 129I/127I is up to 10(-4). The marine environment, i.e. the oceans, is the major source of iodine with average concentrations of around 60 mirogL(-1) iodine in seawater. Brown algae accumulate iodine at high levels of up to 1.0% of dry weight, and therefore they are an ideal bioindicator for studying the levels of 127I and 129I in the marine environment. A radiochemical neutron activation analysis (RNAA) method, developed at our laboratory, was used for 129I determination in the brown alga Fucus virsoides (Donati) J. Agardh, and the same technique of RNAA was used for total 127I determination. The samples were collected along the coast of the Gulf of Trieste and the West coast of Istria in the North Adriatic Sea in the period from 2005 to 2006. Values of the 129I/127I ratio up to 10(-9) were found, which is in agreement with the present average global distribution of 129I. The levels of stable iodine found were in the range from 235 to 506 microg g(-1) and the levels of 129I from 1.7 to 7.3 x 10(-3)Bq kg(-1) (2.6-10.9 x 10(-7) microg g(-1)), on a dry matter basis.

  8. Respiratory strategy is a major determinant of [3H]water and [14C]chlorpyrifos uptake in aquatic insects

    USGS Publications Warehouse

    Buchwalter, D.B.; Jenkins, J.J.; Curtis, L.R.

    2002-01-01

    Despite the extensive use of aquatic insects to evaluate freshwater ecosystem health, little is known about the underlying factors that result in sensitivity differences between taxa. Organismal characteristics (respiratory strategy and body size) were used to explore the rates of [3H]H2O and [14)C]chlorpyrifos accumulation in aquatic insects. Ten aquatic insect taxa, including ephemeropteran, trichopteran, dipteran, hemipteran, and coleopteran species, were exposed to [14C]chlorpyrifos (240 ng??L-1) and [3H]H2O for up to 12 h. Because exchange epithelial surfaces on the)integument are permeable to water, [3H]H2O was used as a quantitative surrogate for exposed cellular surface area.) [14C]Chlorpyrifos uptake rates were highly correlated with water permeability in all 10 taxa tested and largely covaried with body size and respiratory strategy. Rates were highest among smaller organisms on a per-weight basis and in taxa with relatively large external cellular surfaces such as gills. Air-breathing taxa were significantly less permeable to both [3)HH20 and [14C)C]chlorpyrifos. A method for labeling exposed epithelial surfaces with a fluorescent dye was developed. This technique allowed discrimination between exchange epithelium and barrier tissue on the integument. Fluorescent dye distributions on the body surface provided a rapid method for estimating exposed epithelium consistent with [3H]H2O and [14)C]chlorpyrifos accumulation.

  9. Association rate constants for reactions between resonance-stabilized radicals: C 3H 3 + C 3H 3, C 3H 3 + C 3H 5, and C 3H 5 + C 3H 5

    DOE PAGES

    Georgievskii, Yuri; Miller, James A.; Klippenstein, Stephen J.

    2007-05-18

    Reactions between resonance-stabilized radicals play an important role in combustion chemistry. The theoretical prediction of rate coefficients and product distributions for such reactions is complicated by the fact that the initial complex-formation steps and some dissociation steps are barrierless. In this work, direct variable reaction coordinate transition state theory (VRC-TST) is used to predict accurately the association rate constants for the self and cross reactions of propargyl and allyl radicals. For each reaction, a set of multifaceted dividing surfaces is used to account for the multiple possible addition channels. Because of their resonant nature the geometric relaxation of the radicalsmore » is important. Here, the effect of this relaxation is explicitly calculated with the UB3LYP/cc-pvdz method for each mutual orientation encountered in the configurational integrals over the transition state dividing surfaces. The final energies are obtained from CASPT2/cc-pvdz calculations with all π-orbitals in the active space. Evaluations along the minimum energy path suggest that basis set corrections are negligible. The VRC-TST approach was also used to calculate the association rate constant and the corresponding number of states for the C 6H 5 + HC 6H 6 exit channel of the C 3H 3 + C 3H 3 reaction, which is also barrierless. For this reaction, the interaction energies were evaluated with the CASPT2(2e,2o)/cc-pvdz method and a 1-D correction is included on the basis of CAS+1+2+QC/aug-cc-pvtz calculations for the CH 3 + H reference system. For the C 3H 3 + C 3H 3 reaction, the VRC-TST results for the energy and angular momentum resolved numbers of states in the entrance channels and in the C 6H 5 + H exit channel are incorporated in a master equation simulation to determine the temperature and pressure dependence of the phenomenological rate coefficients. The rate constants for the C 3H 3 + C 3H 3 and C 3H 5 + C 3H 5 self-reactions compare favorably

  10. Crystal structure, quantum mechanical investigation, IR and NMR spectroscopy of two new organic salts: (C8H12NO)·[NO3] (I) and (C8H14N4)·[ClO4]2 (II)

    NASA Astrophysics Data System (ADS)

    Bayar, I.; Khedhiri, L.; Soudani, S.; Lefebvre, F.; Pereira da Silva, P. S.; Ben Nasr, C.

    2018-06-01

    Two new organic-inorganic hybrid materials, 4-methoxybenzylammonium nitrate, (C8H12NO)·[NO3] (I), and 2-(1-piperazinyl)pyrimidinium bis(perchlorate), (C8H14N4)·[ClO4]2(II), have been synthesized by an acid/base reaction at room temperature, their structures were determined by single crystal X-ray diffraction. Compound (I) crystallizes in the orthorhombic system and Pnma space group with a = 15.7908 (7), b = 6.8032 (3), c = 8.7091 (4) Å, V = 935.60 (7) Å3 with Z = 4. Full-matrix least-squares refinement converged at R = 0.038 and wR(F2) = 0.115. Compound (II) belongs to the monoclinic system, space group P21/c with the following parameters: a = 10.798(2), b = 7.330(1), c = 21.186(2) Å, β = 120.641 (4)°, V = 1442.7 (3) Å3and Z = 4. The structure was refined to R = 0.044, wR(F2) = 0.132. In the structures of (I) and (II), the anionic and cationic entities are interconnected by hydrogen bonding contacts forming three-dimensional networks. Intermolecular interactions were investigated by Hirshfeld surfaces and the contacts of the four different chloride atoms in (II) were compared. The Molecular Electrostatic Potential (MEP) maps and the HOMO and LUMO energy gaps of both compounds were computed. The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid-state 13C, 35Cl and 15N NMR spectroscopy. DFT calculations allowed the attribution of the IR and NMR bands.

  11. 14 CFR 65.129 - Performance standards.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 2 2013-01-01 2013-01-01 false Performance standards. 65.129 Section 65.129 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Parachute Riggers § 65.129 Performance...

  12. 14 CFR 65.129 - Performance standards.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 2 2012-01-01 2012-01-01 false Performance standards. 65.129 Section 65.129 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Parachute Riggers § 65.129 Performance...

  13. 14 CFR 65.129 - Performance standards.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 2 2014-01-01 2014-01-01 false Performance standards. 65.129 Section 65.129 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Parachute Riggers § 65.129 Performance...

  14. 14 CFR 65.129 - Performance standards.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 2 2011-01-01 2011-01-01 false Performance standards. 65.129 Section 65.129 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Parachute Riggers § 65.129 Performance...

  15. 14 CFR 65.129 - Performance standards.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 2 2010-01-01 2010-01-01 false Performance standards. 65.129 Section 65.129 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) AIRMEN CERTIFICATION: AIRMEN OTHER THAN FLIGHT CREWMEMBERS Parachute Riggers § 65.129 Performance...

  16. MICROWAVE SPECTRA AND GEOMETRIES OF C2H_{2\\cdots AgI} and C2H_{4\\cdots AgI}

    NASA Astrophysics Data System (ADS)

    Stephens, Susanna L.; Tew, David Peter; Walker, Nick; Legon, Anthony

    2015-06-01

    A chirped-pulse Fourier transform microwave spectrometer has been used to measure the microwave spectra of both C2H_{2\\cdots AgI} and C2H_{4\\cdots AgI}. These complexes are generated via laser ablation at 532 nm of a silver surface in the presence of CF3I and either C2H_{2} or C2H_{4} and argon and are stabilized by a supersonic expansion. Rotational (A0, B0, C0) and centrifugal distortion constants (ΔJ and ΔJK) of each molecule have been determined as well the nuclear electric quadrupole coupling constants the iodine atom (χaa(I) and χbb-χcc(I)). The spectrum of each molecule is consistent with a C2v structure in which the metal atom interacts with the π-orbital of the ethene or ethyne molecule. Isotopic substitutions of atoms within the C2H_{2} or C2H_{4} subunits are in progress and in conjunction with high level ab initio calculations will allow for accurate determination of the geometry of each molecule. These to complexes are put in the context of the recently studied H2S\\cdots AgI, OC\\cdotsAgI, H3N\\cdots AgI and (CH3)_{3N\\cdots AgI}. S.Z. Riaz, S.L. Stephens, W. Mizukami, D.P. Tew, N.R. Walker, A.C. Legon, Chem. Phys. Let., 531, 1-12 (2012) S.L. Stephens, W. Mizukami, D.P. Tew, N.R. Walker, A.C. Legon, J. Chem. Phys., 136(6), 064306 (2012) D.M. Bittner, D.P. Zaleski, S.L. Stephens, N.R. Walker, A.C. Legon, Study in progress.

  17. 14 CFR 21.129 - Tests: propellers.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 1 2012-01-01 2012-01-01 false Tests: propellers. 21.129 Section 21.129... PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate § 21.129 Tests: propellers. Each person manufacturing propellers under a type certificate must give each variable pitch propeller an acceptable...

  18. 14 CFR 21.129 - Tests: propellers.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 1 2014-01-01 2014-01-01 false Tests: propellers. 21.129 Section 21.129... PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate § 21.129 Tests: propellers. Each person... functional test to determine if it operates properly throughout the normal range of operation. ...

  19. 14 CFR 21.129 - Tests: propellers.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 1 2013-01-01 2013-01-01 false Tests: propellers. 21.129 Section 21.129... PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate § 21.129 Tests: propellers. Each person... functional test to determine if it operates properly throughout the normal range of operation. ...

  20. 14 CFR 21.129 - Tests: propellers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 1 2011-01-01 2011-01-01 false Tests: propellers. 21.129 Section 21.129... PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate Only § 21.129 Tests: propellers. Each person manufacturing propellers under a type certificate only shall give each variable pitch propeller an...

  1. 14 CFR 21.129 - Tests: propellers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Tests: propellers. 21.129 Section 21.129... PROCEDURES FOR PRODUCTS AND PARTS Production Under Type Certificate Only § 21.129 Tests: propellers. Each... acceptable functional test to determine if it operates properly throughout the normal range of operation. ...

  2. 14 CFR 129.20 - Digital flight data recorders.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Digital flight data recorders. 129.20... § 129.20 Digital flight data recorders. No person may operate an aircraft under this part that is registered in the United States unless it is equipped with one or more approved flight recorders that use a...

  3. 14 CFR 129.20 - Digital flight data recorders.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Digital flight data recorders. 129.20... § 129.20 Digital flight data recorders. No person may operate an aircraft under this part that is registered in the United States unless it is equipped with one or more approved flight recorders that use a...

  4. 14 CFR 129.20 - Digital flight data recorders.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Digital flight data recorders. 129.20... § 129.20 Digital flight data recorders. No person may operate an aircraft under this part that is... digital method of recording and storing data and a method of readily retrieving that data from the storage...

  5. 14 CFR 129.20 - Digital flight data recorders.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Digital flight data recorders. 129.20... § 129.20 Digital flight data recorders. No person may operate an aircraft under this part that is... digital method of recording and storing data and a method of readily retrieving that data from the storage...

  6. 14 CFR 129.201 - SFAR No. 111-Lavatory Oxygen Systems.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false SFAR No. 111-Lavatory Oxygen Systems. 129.201 Section 129.201 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Special Federal Aviation Regulations § 129.201 SFAR No. 111—Lavatory Oxygen Systems. The requirements of...

  7. 14 CFR 129.201 - SFAR No. 111-Lavatory Oxygen Systems.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false SFAR No. 111-Lavatory Oxygen Systems. 129.201 Section 129.201 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Special Federal Aviation Regulations § 129.201 SFAR No. 111—Lavatory Oxygen Systems. The requirements of...

  8. 14 CFR 129.201 - SFAR No. 111-Lavatory Oxygen Systems.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false SFAR No. 111-Lavatory Oxygen Systems. 129.201 Section 129.201 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF... Special Federal Aviation Regulations § 129.201 SFAR No. 111—Lavatory Oxygen Systems. The requirements of...

  9. Oxidation of 2,6-di-tert-butyl-4-methylphenol. The structure of C14H22O3

    USGS Publications Warehouse

    Yohe, G.R.; Dunbar, J.E.; Lansford, M.W.; Pedrotti, R.L.; Scheidt, F.M.; Lee, F.G.H.; Smith, E.C.

    1959-01-01

    The acidic compound C14H22O3, previously reported without assignment of structure as an oxidation product of 2,6-di-tert-butyl-4-methylphenol, is now believed to be DL-trans-5,6-di-tert-butyl-2-hydroxy-1,4-diketo-2-cyclohexene (I). Chemical properties are described and infrared spectra are presented in support of this structure. This structure is of interest in relation to the problem of the existence of o-di-tert-alkylbenzene derivatives. The relatively easy racemization of optically active I suggests that its completely enolized form, 5,6-di-tert-butyl-1,2,4-trihydroxybenzene, is capable of transitory existence.

  10. Historical record of nuclear activities from 129I in corals from the northern hemisphere (Philippines).

    PubMed

    Bautista, Angel T; Matsuzaki, Hiroyuki; Siringan, Fernando P

    2016-11-01

    Iodine-129 is a long-lived fission product that is majorly released in human nuclear activities (HNA) such as nuclear bomb testing, nuclear fuel reprocessing, and nuclear accidents. It is a good environmental tracer and former measurements of 129 I in corals from the southern hemisphere show the increasing trend of 129 I concentrations in the marine environment caused by HNA. Here we show time series of 129 I/ 127(stable) I isotopic ratios in two coral cores from the northern hemisphere (Philippines) and how these record 129 I released from HNA in even greater, unprecedented detail. Corals were taken from the Pacific Ocean (Baler) and South China Sea (Parola) sides of the Philippines. We observed nearly identical peaks ( 129 I/ 127 I ∼ 31.5 × 10 -12 ) in both the Baler and Parola records, each attributed to the year 1962 - the year with the highest recorded amount of 129 I release from nuclear bomb testing. This 1962 129 I bomb signal offers a new time marker that can be used to establish or confirm age models of corals, comparable to or possibly better than the well-known coral 14 C bomb peak. We also observed nuclear fuel reprocessing and Chernobyl accident 129 I signals in years 1977, 1980, and 1986, concurrently in Parola and with 9 to 11-year lags in Baler. This discrepancy in timing suggests that 129 I was transported to the South China Sea and Pacific Ocean sides of the Philippines directly from the atmosphere and through prevailing ocean currents, respectively. Lastly, we observed surprisingly high 129 I/ 127 I isotopic ratios (i.e., 22.8 to 38.9 × 10 -12 ) in the Parola record after the year 1996, which is in contrast to the decreasing trend observed in the Baler record and in published 129 I releases of different HNA. These results possibly indicate the presence of unknown sources of 129 I in the South China Sea region. Copyright © 2016 Elsevier Ltd. All rights reserved.

  11. Evaluation of the 129I Half-Life Value Through Analyses of Primitive Meteorites

    NASA Astrophysics Data System (ADS)

    Pravdivtseva, Olga; Meshik, Alex; Hohenberg, Charles M.

    The preserved record of decay of now-extinct 129I into 129Xe forms the basis of the I-Xe chronometer. Comparison of the high precision I-Xe and Pb-Pb ages of chondrules and pure mineral phases separated from eight meteorites suggests the 17.5 ÷ 14.6 Ma range for the 129I half-life, assuming that the 235U and 238U half-lives are correct. The mean value of 16 Ma indicates that the 15.7 Ma half-life of 129I used here for the I-Xe age calculations is most probably correct. Since the 129I half-life value only affects the relative I-Xe ages, the few Ma relative to the Shallowater standard, the absolute I-Xe ages are almost immune to this uncertainty in the 129I half-life.

  12. 14 CFR 129.19 - Air traffic rules and procedures.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Air traffic rules and procedures. 129.19 Section 129.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... establish procedures to assure that each of its pilots has the knowledge required by paragraph (a) of this...

  13. 14 CFR 129.19 - Air traffic rules and procedures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Air traffic rules and procedures. 129.19 Section 129.19 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION... establish procedures to assure that each of its pilots has the knowledge required by paragraph (a) of this...

  14. Infrared spectra of ovalene (C32H14) and hydrogenated ovalene (C32H15˙) in solid para-hydrogen.

    PubMed

    Tsuge, Masashi; Bahou, Mohammed; Wu, Yu-Jong; Allamandola, Louis; Lee, Yuan-Pern

    2016-10-19

    We report the infrared (IR) spectra of ovalene (C 32 H 14 ) and hydrogenated ovalene (C 32 H 15 ˙) in solid para-hydrogen (p-H 2 ). The hydrogenated ovalene and protonated ovalene were generated from electron bombardment of a mixture of ovalene and p-H 2 during deposition of a matrix at 3.2 K. The features that decreased with time have been previously assigned to 7-C 32 H 15 + , the most stable isomer of protonated ovalene (Astrophys. J., 2016, 825, 96). The spectral features that increased with time are assigned to the most stable isomer of hydrogenated ovalene (7-C 32 H 15 ˙) based on the expected chemistry and on a comparison with the vibrational wavenumbers and IR intensities predicted by the B3PW91/6-311++G(2d,2p) method. The mechanism of formation of 7-C 32 H 15 ˙ is discussed according to the observed changes in intensity and calculated energetics of possible reactions of H + C 32 H 14 and isomerization of C 32 H 15 ˙. The formation of 7-C 32 H 15 ˙ is dominated by the reaction H + C 32 H 14 → 7-C 32 H 15 ˙, implying that, regardless of the presence of a barrier, the hydrogenation of polycyclic aromatic hydrocarbons occurs even at 3.2 K.

  15. Experimental and ab initio studies of the reactive processes in gas phase i-C{sub 3}H{sub 7}Br and i-C{sub 3}H{sub 7}OH collisions with potassium ions

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

    López, E.; Lucas, J. M.; Andrés, J. de

    2014-10-28

    Collisions between potassium ions and neutral i-C{sub 3}H{sub 7}Br and i-C{sub 3}H{sub 7}OH, all in their electronic ground state, have been studied in the 0.10–10.00 eV center of mass (CM) collision energy range, using the radiofrequency-guided ion beam technique. In K{sup +} + i-C{sub 3}H{sub 7}Br collisions KHBr{sup +} formation was observed and quantified, while the analogous KH{sub 2}O{sup +} formation in K{sup +} + i-C{sub 3}H{sub 7}OH was hardly detected. Moreover, formation of the ion-molecule adducts and their decomposition leading to C{sub 3}H{sub 7}{sup +} and either KBr or KOH, respectively, have been observed. For all these processes, absolutemore » cross-sections were measured as a function of the CM collision energy. Ab initio structure calculations at the MP2 level have given information about the potential energy surfaces (PESs) involved. In these, different stationary points have been characterized using the reaction coordinate method, their connectivity being ensured by using the intrinsic-reaction-coordinate method. From the measured excitation function for KHBr{sup +} formation the corresponding thermal rate constant at 303 K has been calculated. The topology of the calculated PESs allows an interpretation of the main features of the reaction dynamics of both systems, and in particular evidence the important role played by the potential energy wells in controlling the reactivity for the different reaction channels.« less

  16. Speciation of 127I and 129I in atmospheric aerosols at Risø, Denmark: insight into sources of iodine isotopes and their species transformations

    NASA Astrophysics Data System (ADS)

    Zhang, Luyuan; Hou, Xiaolin; Xu, Sheng

    2016-02-01

    Speciation analysis of iodine in aerosols is a very useful approach for understanding geochemical cycling of iodine in the atmosphere. In this study, overall iodine species, including water-soluble iodine species (iodide, iodate and water-soluble organic iodine), NaOH-soluble iodine, and insoluble iodine have been determined for 129I and 127I in the aerosols collected at Risø, Denmark, during March and May 2011 (shortly after the Fukushima nuclear accident) and in December 2014. The measured concentrations of total iodine are in the range of 1.04-2.48 ng m-3 for 127I and (11.3-97.0) × 105 atoms m-3 for 129I, corresponding to 129I / 127I atomic ratios of (17.8-86.8) × 10-8. The contribution of Fukushima-derived 129I (peak value of 6.3 × 104 atoms m-3) is estimated to be negligible (less than 6 %) compared to the total 129I concentration in northern Europe. The concentrations and species of 129I and 127I in the aerosols are found to be strongly related to their sources and atmospheric pathways. Aerosols that were transported over the contaminated seas contained higher concentrations of 129I than aerosols transported over the European continent. The high 129I concentrations of the marine aerosols are attributed to secondary emission of marine discharged 129I in the contaminated seawater in the North Sea, North Atlantic Ocean, English Channel, Kattegat, etc., rather than direct gaseous release from the European nuclear reprocessing plants (NRPs). Water-soluble iodine was found to be a minor fraction to the total iodine for both 127I (7.8-13.7 %) and 129I (6.5-14.1 %) in ocean-derived aerosols, but accounted for 20.2-30.3 % for 127I and 25.6-29.5 % for 129I in land-derived aerosols. Iodide was the predominant form of water-soluble iodine, accounting for more than 97 % of the water-soluble iodine. NaOH-soluble iodine seems to be independent of the sources of aerosols. The significant proportion of 129I and 127I found in NaOH-soluble fractions is likely bound with

  17. Automated video analysis system reveals distinct diurnal behaviors in C57BL/6 and C3H/HeN mice.

    PubMed

    Adamah-Biassi, E B; Stepien, I; Hudson, R L; Dubocovich, M L

    2013-04-15

    Advances in rodent behavior dissection using automated video recording and analysis allows detailed phenotyping. This study compared and contrasted 15 diurnal behaviors recorded continuously using an automated behavioral analysis system for a period of 14 days under a 14/10 light/dark cycle in single housed C3H/HeN (C3H) or C57BL/6 (C57) male mice. Diurnal behaviors, recorded with minimal experimental interference and analyzed using phenotypic array and temporal distribution analysis showed bimodal and unimodal profiles in the C57 and C3H mice, respectively. Phenotypic array analysis revealed distinct behavioral rhythms in Activity-Like Behaviors (i.e. walk, hang, jump, come down) (ALB), Exploration-Like Behaviors (i.e. dig, groom, rear up, sniff, stretch) (ELB), Ingestion-Like Behaviors (i.e. drink, eat) (ILB) and Resting-Like Behaviors (i.e. awake, remain low, rest, twitch) (RLB) of C3H and C57 mice. Temporal distribution analysis demonstrated that strain and time of day affects the magnitude and distribution of the spontaneous homecage behaviors. Wheel running activity, water and food measurements correlated with timing of homecage behaviors. Subcutaneous (3 mg/kg, sc) or oral (0.02 mg/ml, oral) melatonin treatments in C57 mice did not modify either the total 24 h magnitude or temporal distribution of homecage behaviors when compared with vehicle treatments. We conclude that C3H and C57 mice show different spontaneous activity and behavioral rhythms specifically during the night period which are not modulated by melatonin. Copyright © 2013 Elsevier B.V. All rights reserved.

  18. Threshold groundwater ages and young water fractions estimated from 3H, 3He, and 14C

    NASA Astrophysics Data System (ADS)

    Kirchner, James; Jasechko, Scott

    2016-04-01

    It is widely recognized that a water sample taken from a running stream is not described by a single age, but rather by a distribution of ages. It is less widely recognized that the same principle holds true for groundwaters, as indicated by the commonly observed discordances between model ages obtained from different tracers (e.g., 3H vs 14C) in the same sample. Water age distributions are often characterized by their mean residence times (MRT's). However, MRT estimates are highly uncertain because they depend on the shape of the assumed residence time distribution (in particular on the thickness of the long-time tail), which is difficult or impossible to constrain with data. Furthermore, because MRT's are typically nonlinear functions of age tracer concentrations, they are subject to aggregation bias. That is, MRT estimates derived from a mixture of waters with different ages (and thus different tracer concentrations) will systematically underestimate the mixture's true mean age. Here, building on recent work with stable isotope tracers in surface waters [1-3], we present a new framework for using 3H, 3He and 14C to characterize groundwater age distributions. Rather than describing groundwater age distributions by their MRT, we characterize them by the fraction of the distribution that is younger or older than a threshold age. The threshold age that separates "young" from "old" water depends on the characteristics of the specific tracer, including its history of atmospheric inputs. Our approach depends only on whether a given slice of the age distribution is younger or older than the threshold age, but not on how much younger or older it is. Thus our approach is insensitive to the tails of the age distribution, and is therefore relatively unaffected by uncertainty in the distribution's shape. Here we show that concentrations of 3H, 3He, and 14C are almost linearly related to the fractions of water that are younger or older than specified threshold ages. These

  19. Automated Video Analysis System Reveals Distinct Diurnal Behaviors in C57BL/6 and C3H/HeN Mice

    PubMed Central

    Adamah-Biassi, E. B.; Stepien, I.; Hudson, R.L.; Dubocovich, M.L.

    2013-01-01

    Advances in rodent behavior dissection using automated video recording and analysis allows detailed phenotyping. This study compared and contrasted 15 diurnal behaviors recorded continuously using an automated behavioral analysis system for a period of 14 days under a 14/10 light/dark cycle in single housed C3H/HeN (C3H) or C57BL/6 (C57) male mice. Diurnal behaviors, recorded with minimal experimental interference and analyzed using phenotypic array and temporal distribution analysis showed bimodal and unimodal profiles in the C57 and C3H mice, respectively. Phenotypic array analysis revealed distinct behavioral rhythms in activity-like behaviors (i.e. walk, hang, jump, come down) (ALB), exploration-like behaviors (i.e. dig, groom, rear up, sniff, stretch) (ELB), ingestion-like behaviors (i.e. drink, eat) (ILB) and resting-like behaviors (i.e. awake, remain low, rest, twitch) (RLB) of C3H and C57 mice. Temporal analysis demonstrated that strain and time of day affects the magnitude and distribution of the spontaneous homecage behaviors. Wheel running activity, water and food measurements correlated with timing of homecage behaviors. Subcutaneous (3 mg/kg, sc) or oral (0.02 mg/ml, oral) melatonin treatments in C57 mice did not modify either the total 24 hr magnitude or temporal distribution of homecage behaviors when compared with vehicle treatments. We conclude that C3H and C57 mice show different spontaneous activity and behavioral rhythms specifically during the night period which are not modulated by melatonin. PMID:23337734

  20. Photodissociation of pyrene cations: structure and energetics from C16H10(+) to C14(+) and almost everything in between.

    PubMed

    West, Brandi; Useli-Bacchitta, Francesca; Sabbah, Hassan; Blanchet, Valérie; Bodi, Andras; Mayer, Paul M; Joblin, Christine

    2014-09-11

    The unimolecular dissociation of the pyrene radical cation, C16H10(+•), has been explored using a combination of computational techniques and experimental approaches, such as multiple photon absorption in the cold ion trap Piège à Ions pour la Recherche et l'Etude de Nouvelles Espèces Astrochimiques (PIRENEA) and imaging photoelectron photoion coincidence spectrometry (iPEPICO). In total, 22 reactions, involving the fragmentation cascade (H, C2H2, and C4H2 loss) from the pyrene radical cation down to the C14(+•) fragment ion, have been studied using PIRENEA. Branching ratios have been measured for reactions from C16H10(+•), C16H8(+•), and C16H5(+). Density functional theory calculations of the fragmentation pathways observed experimentally and postulated theoretically lead to 17 unique structures. One important prediction is the opening of the pyrene ring system starting from the C16H4(+•) radical. In the iPEPICO experiments, only two reactions could be studied, namely, R1 C16H10(+•) → C16H9(+) + H (m/z = 201) and R2 C16H9(+) → C16H8(+•) + H (m/z = 200). The activation energies for these reactions were determined to be 5.4 ± 1.2 and 3.3 ± 1.1 eV, respectively.

  1. Monohalogenated ferrocenes C5H5FeC5H4 X (X = Cl, Br and I) and a second polymorph of C5H5FeC5H4I

    PubMed Central

    Romanov, Alexander S.; Mulroy, Joseph M.; Khrustalev, Victor N.; Antipin, Mikhail Yu.; Timofeeva, Tatiana V.

    2009-01-01

    The structures of the three title monosubstituted ferrocenes, namely 1-chloro­ferrocene, [Fe(C5H5)(C5H4Cl)], (I), 1-bromo­ferrocene, [Fe(C5H5)(C5H4Br)], (II), and 1-iodo­ferrocene, [Fe(C5H5)(C5H4I)], (III), were determined at 100 K. The chloro- and bromo­ferrocenes are isomorphous crystals. The new triclinic polymorph [space group P , Z = 4, T = 100 K, V = 943.8 (4) Å3] of iodo­ferrocene, (III), and the previously reported monoclinic polymorph of (III) [Laus, Wurst & Schottenberger (2005 ▶). Z. Kristallogr. New Cryst. Struct. 220, 229–230; space group Pc, Z = 4, T = 100 K, V = 924.9 Å3] were obtained by crystallization from ethanolic solutions at 253 and 303 K, respectively. All four phases contain two independent mol­ecules in the unit cell. The relative orientations of the cyclo­penta­dienyl (Cp) rings are eclipsed and staggered in the independent mol­ecules of (I) and (II), while (III) demonstrates only an eclipsed conformation. The triclinic and monoclinic polymorphs of (III) contain nonbonded inter­molecular I⋯I contacts, causing different packing modes. In the triclinic form of (III), the mol­ecules are arranged in zigzag tetra­mers, while in the monoclinic form the mol­ecules are arranged in zigzag chains along the a axis. Crystallographic data for (III), along with the computed lattice energies of the two polymorphs, suggest that the monoclinic form is more stable. PMID:19893225

  2. 14 CFR 129.11 - Amendment, suspension and termination of operations specifications.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Amendment, suspension and termination of operations specifications. 129.11 Section 129.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... AND OPERATIONS OPERATIONS: FOREIGN AIR CARRIERS AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT...

  3. 14 CFR 129.11 - Amendment, suspension and termination of operations specifications.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Amendment, suspension and termination of operations specifications. 129.11 Section 129.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... AND OPERATIONS OPERATIONS: FOREIGN AIR CARRIERS AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT...

  4. 14 CFR 129.11 - Amendment, suspension and termination of operations specifications.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Amendment, suspension and termination of operations specifications. 129.11 Section 129.11 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION... AND OPERATIONS OPERATIONS: FOREIGN AIR CARRIERS AND FOREIGN OPERATORS OF U.S.-REGISTERED AIRCRAFT...

  5. Distribution and sources of (129)I in rivers of the Baltic region.

    PubMed

    Aldahan, A; Kekli, A; Possnert, G

    2006-01-01

    The concentration of (129)I was measured in 54 river waters discharging into the Baltic Sea from Sweden, Finland, Estonia, Latvia, Lithuania, Poland and Germany. Sample collection was performed during a well-bracketed time interval (June-July 1999), thus allowing comparison of the rivers over a wide latitude range without the effect of long temporal spread. Although there is no direct input of anthropogenic (129)I in the watersheds, the concentration of the isotope is about two to three orders of magnitude higher than the expected pre-nuclear era natural values in the rivers of Finland and northern Sweden, and in the rivers of southern Sweden, Lithuania, Estonia, Latvia, Poland and Germany; the (129)I concentration may reach five orders of magnitude higher. Furthermore, there are significant correlations between the (129)I concentration and latitude and/or distance from the North Sea and between (129)I and Cl. These findings suggest seawater as a main source of (129)I to the rivers through atmospheric transport. Of the many chemical parameters investigated, the pH may account for some of the variability in (129)I concentrations of the rivers. The contribution from nuclear weapon tests and the Chernobyl accident to the riverine (129)I is insignificant compared to the releases from the nuclear fuel reprocessing facilities. The total flux of (129)I by rivers to the Baltic Sea and related basins represents minor amounts of the isotope pool in these marine waters. External radioactivity hazards from (129)I are considered to be negligible in the Baltic region. However, as the main (129)I intake to the human body is likely through water, due to the large amount of daily water consumption, more concern should be given to internal radioactivity hazard that may be associated with the isotope's localized elevated concentration in the human organs.

  6. Metabolism of D-[1-3H]glucose, D-[2-3H]glucose, D-[5-3H]glucose, D-[6-3H]glucose and D-[U-14C]glucose by rat and human erythrocytes incubated in the presence of H2O or D2O.

    PubMed

    Conget, I; Malaisse, W J

    1995-02-01

    The present study investigates whether heavy water affects the efficiency of 3HOH production from D-[1-3H]glucose, D-[2-3H]glucose, D-[5-3H]glucose and D-[6-3H]glucose relative to the total generation of tritiated metabolites produced by either rat or human erythrocytes. The relative 3HOH yield was close to 95% with D-[5-3H]glucose, 72% with D-[2-3H]glucose, 22-32% with D-[1-3H]glucose, and only 12% with D-[6-3H]glucose. In the latter case, the comparison of the specific radioactivity of intracellular and extracellular acidic metabolites, expressed relative to that of 14C-labelled metabolites produced from D-[U-14C]glucose, indicated that the generation of 3HOH from D-[6-3H]glucose occurs at distal metabolic steps, such as the partial reversion of the pyruvate kinase reaction or the interconversion of pyruvate and L-alanine in the reaction catalysed by glutamate-pyruvate transaminase. As a rule, the substitution of H2O by D2O only caused minor to negligible changes in the relative 3HOH yield. This implies that the unexpectedly high deuteration of 13C-labelled D-glucose metabolites recently documented in erythrocytes exposed to D2O cannot be attributed to any major interference of heavy water with factors regulating both the deuteration and detritiation efficiency, such as the enzyme-to-enzyme tunnelling of specific glycolytic intermediates.

  7. Improved potentials and Born-Oppenheimer corrections by new measurements of transitions of 129I2 and 127I 129I in the B3 Pi_O^+_u - X1 Σ^+_g band system

    NASA Astrophysics Data System (ADS)

    Salumbides, E. J.; Eikema, K. S. E.; Ubachs, W.; Hollenstein, U.; Knöckel, H.; Tiemann, E.

    2008-04-01

    The light from one single frequency cw laser was employed in a double saturation spectroscopy experiment to record high resolution spectra of 129I2 and 127I129I together with spectra of 127I2 which is used as a simultaneous frequency reference. Two separate saturation spectroscopy set ups were used. The frequencies of lines of 129I2 and 127I129I were determined with respect to lines of 127I2. More than 380 frequency differences between lines of 127I2 and of the other isotopomers have been included in the data set. By a direct potential fit a precise description of the potential energy curves of the B and the X state and of effective Born-Oppenheimer correction functions valid for all three isotopomers of I2 are given.

  8. TMEM129 is a Derlin-1 associated ERAD E3 ligase essential for virus-induced degradation of MHC-I.

    PubMed

    van den Boomen, Dick J H; Timms, Richard T; Grice, Guinevere L; Stagg, Helen R; Skødt, Karsten; Dougan, Gordon; Nathan, James A; Lehner, Paul J

    2014-08-05

    The US11 gene product of human cytomegalovirus promotes viral immune evasion by hijacking the endoplasmic reticulum (ER)-associated degradation (ERAD) pathway. US11 initiates dislocation of newly translocated MHC I from the ER to the cytosol for proteasome-mediated degradation. Despite the critical role for ubiquitin in this degradation pathway, the responsible E3 ligase is unknown. In a forward genetic screen for host ERAD components hijacked by US11 in near-haploid KBM7 cells, we identified TMEM129, an uncharacterized polytopic membrane protein. TMEM129 is essential and rate-limiting for US11-mediated MHC-I degradation and acts as a novel ER resident E3 ubiquitin ligase. TMEM129 contains an unusual cysteine-only RING with intrinsic E3 ligase activity and is recruited to US11 via Derlin-1. Together with its E2 conjugase Ube2J2, TMEM129 is responsible for the ubiquitination, dislocation, and subsequent degradation of US11-associated MHC-I. US11 engages two degradation pathways: a Derlin-1/TMEM129-dependent pathway required for MHC-I degradation and a SEL1L/HRD1-dependent pathway required for "free" US11 degradation. Our data show that TMEM129 is a novel ERAD E3 ligase and the central component of a novel mammalian ERAD complex.

  9. The interstellar chemistry of C3H and C3H2 isomers

    PubMed Central

    Loison, Jean-Christophe; Agúndez, Marcelino; Wakelam, Valentine; Roueff, Evelyne; Gratier, Pierre; Marcelino, Núria; Nuñez Reyes, Dianailys; Cernicharo, José; Gerin, Maryvonne

    2017-01-01

    We report the detection of linear and cyclic isomers of C3H and C3H2 towards various starless cores and review the corresponding chemical pathways involving neutral (C3Hx with x=1,2) and ionic (C3Hx+ with x = 1,2,3) isomers. We highlight the role of the branching ratio of electronic Dissociative Recombination (DR) reactions of C3H2+ and C3H3+ isomers showing that the statistical treatment of the relaxation of C3H* and C3H2* produced in these DR reactions may explain the relative c,l-C3H and c,l-C3H2 abundances. We have also introduced in the model the third isomer of C3H2 (HCCCH). The observed cyclic-to-linear C3H2 ratio vary from 110 ± 30 for molecular clouds with a total density around 1×104 molecules.cm-3 to 30 ± 10 for molecular clouds with a total density around 4×105 molecules.cm-3, a trend well reproduced with our updated model. The higher ratio for low molecular cloud densities is mainly determined by the importance of the H + l-C3H2 → H + c-C3H2 and H + t-C3H2 → H + c-C3H2 isomerization reactions. PMID:29142332

  10. The interstellar chemistry of C3H and C3H2 isomers

    NASA Astrophysics Data System (ADS)

    Loison, Jean-Christophe; Agúndez, Marcelino; Wakelam, Valentine; Roueff, Evelyne; Gratier, Pierre; Marcelino, Núria; Reyes, Dianailys Nuñez; Cernicharo, José; Gerin, Maryvonne

    2017-10-01

    We report the detection of linear and cyclic isomers of C3H and C3H2 towards various starless cores and review the corresponding chemical pathways involving neutral (C3Hx with x = 1,2) and ionic (C3Hx+ with x = 1,2,3) isomers. We highlight the role of the branching ratio of electronic dissociative recombination (DR) reactions of C3H2+ and C3H3+ isomers, showing that the statistical treatment of the relaxation of C3H* and C3H2* produced in these DR reactions may explain the relative c,l-C3H and c,l-C3H2 abundances. We have also introduced in the model the third isomer of C3H2 (HCCCH). The observed cyclic-to-linear C3H2 ratio varies from 110 ± 30 for molecular clouds with a total density of about 1 × 104 molecules cm-3 to 30 ± 10 for molecular clouds with a total density of about 4 × 105 molecules cm-3, a trend well reproduced with our updated model. The higher ratio for molecular clouds with low densities is determined mainly by the importance of the H + l-C3H2 → H + c-C3H2 and H + t-C3H2 → H + c-C3H2 isomerization reactions.

  11. Laser spectroscopy of the A ˜ 2 Σ + - X ˜ 2 Π i band system of l-SiC3H

    NASA Astrophysics Data System (ADS)

    Umeki, Hiroya; Nakajima, Masakazu; Endo, Yasuki

    2015-11-01

    The A ˜ 2 Σ + - X ˜ 2 Π i band system of l-SiC3H in the region 14 700-16 300 cm-1 was re-investigated by laser induced fluorescence (LIF) and fluorescence depletion spectroscopy. Rotational analyses were made for three intense bands 00 0 , 40 1 , and 60 1 70 1 by observing high-resolution LIF excitation spectra. The determined rotational constants demonstrate that SiC3H is linear in the A ˜ state, as is the case in the X ˜ state, and the observed band types are consistent with the vibrational assignments. The ν3 ″ (C1-C2 stretch) level was identified in a newly observed dispersed fluorescence spectrum from the zero-vibrational level of the A ˜ state.

  12. Catalyst-Dependent Chemoselective Formal Insertion of Diazo Compounds into C-C or C-H Bonds of 1,3-Dicarbonyl Compounds.

    PubMed

    Liu, Zhaohong; Sivaguru, Paramasivam; Zanoni, Giuseppe; Anderson, Edward A; Bi, Xihe

    2018-05-08

    A catalyst-dependent chemoselective one-carbon insertion of diazo compounds into the C-C or C-H bonds of 1,3-dicarbonyl species is reported. In the presence of silver(I) triflate, diazo insertion into the C(=O)-C bond of the 1,3-dicarbonyl substrate leads to a 1,4-dicarbonyl product containing an all-carbon α-quaternary center. This reaction constitutes the first example of an insertion of diazo-derived carbenoids into acyclic C-C bonds. When instead scandium(III) triflate was applied as the catalyst, the reaction pathway switched to formal C-H insertion, affording 2-alkylated 1,3-dicarbonyl products. Different reaction pathways are proposed to account for this powerful catalyst-dependent chemoselectivity. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. The new method of real-time detection of 129I2, 129I127I, 127I2 and NO2 in gases using tunable diode laser operating in the range of 632-637 nm

    NASA Astrophysics Data System (ADS)

    Kireev, S. V.; Shnyrev, S. L.

    2018-02-01

    This paper develops the new selective real-time method of 129I2, 129I127I, 127I2 and NO2 detection in gases. Measuring concentrations of molecular iodine is based on fluorescence exciting by the radiation of a tunable diode laser, operating in the red spectral region (632-637 nm), at two or three wavelengths corresponding to the centers of the absorption lines of 129I2, 129I127I and 127I2. Detection of NO2 is performed by measuring the intensity of the tunable diode laser radiation, which passed through the measuring cell. Measured simultaneously, boundary ratios of iodine molecule concentrations measured simultaneously are about 10-6. The sensitivity of nitrogen dioxide detection is 1016 cm-3.

  14. Anthropogenic 129I in the atmosphere: overview over major sources, transport processes and deposition pattern.

    PubMed

    Reithmeier, H; Lazarev, V; Rühm, W; Nolte, E

    2010-10-01

    Wet and, to a lesser extent, dry deposition of atmospheric (129)I are known to represent the dominating processes responsible for (129)I in continental environmental samples that are remote from (129)I sources and not directly influenced by any liquid (129)I release of nuclear installations. Up to now, however, little is known about the major emitters and the related global deposition pattern of (129)I. In this work an overview over major sources of (129)I is given, and hitherto unknown time-dependent releases from these were estimated. Total gaseous (129)I releases from the US and former Soviet reprocessing facilities Hanford, Savannah River, Mayak, Seversk and Zheleznogorsk were found to have been 0.53, 0.27, 1.05, 0.23 and 0.14TBq, respectively. These facilities were thus identified as major airborne (129)I emitters. The global deposition pattern due to the (129)I released, depending on geographic latitude and longitude, and on time was studied using a box model describing the global atmospheric transport and deposition of (129)I. The model predictions are compared to (129)I concentrations measured by means of Accelerator Mass Spectrometry (AMS) in water samples that were collected from various lakes in Asia, Africa, America and New Zealand, and to published values. As a result, both pattern and temporal evolution of (129)I deposition values measured in and calculated for different types of environmental samples are, in general, in good agreement. This supports our estimate on atmospheric (129)I releases and the considered substantial transport and deposition mechanisms in our model calculations. Copyright 2010 Elsevier B.V. All rights reserved.

  15. Structure and function of three novel MHC class I antigens derived from a C3H ultraviolet-induced fibrosarcoma

    PubMed Central

    1986-01-01

    The UV-induced, C3H fibrosarcoma, 1591, expresses at least three unique MHC class I antigens not found on normal C3H tissue. Here we report the complete DNA sequence of the three novel class I genes encoding these molecules, and describe in detail the recognition of the individual products by tumor-reactive and allospecific CTL. Remarkably, although C3H does not appear to express H-2L locus information, this C3H tumor expresses two distinct antigens, termed A149 and A166, which are extremely homologous to each other and to the H-2Ld antigen from BALB/c. The gene encoding the third novel class I antigen from 1591, A216, is quite homologous to H-2Kk) throughout its 3' end. Since all three of these genes account for polymorphic restriction fragments not found in C3H, it is likely that they were derived by recombination from the endogenous class I genes of C3H. The DNA sequence homology of A149, A166, and H-2Ld is especially significant given the functional conservation observed between the products of these genes. Limited sequence substitutions appear to correlate with some of the discrete serological differences observed between these molecules. In addition, both A149 and A166 crossreact, but to differing extents, with H-2Ld at the level of T cell recognition. Our results are consistent with the view that CTL recognize complex conformational determinants on class I molecules, but extend previous observations by comparing a set of antigens with discrete and overlapping structural and functional differences. PMID:3489061

  16. Field-induced spin splitting and anomalous photoluminescence circular polarization in C H3N H3Pb I3 films at high magnetic field

    NASA Astrophysics Data System (ADS)

    Zhang, Chuang; Sun, Dali; Yu, Zhi-Gang; Sheng, Chuan-Xiang; McGill, Stephen; Semenov, Dmitry; Vardeny, Zeev Valy

    2018-04-01

    The organic-inorganic hybrid perovskites show excellent optical and electrical properties for photovoltaic and a myriad of other optoelectronics applications. Using high-field magneto-optical measurements up to 17.5 T at cryogenic temperatures, we have studied the spin-dependent optical transitions in the prototype C H3N H3Pb I3 , which are manifested in the field-induced circularly polarized photoluminescence emission. The energy splitting between left and right circularly polarized emission bands is measured to be ˜1.5 meV at 17.5 T, from which we obtained an exciton effective g factor of ˜1.32. Also from the photoluminescence diamagnetic shift we estimate the exciton binding energy to be ˜17 meV at low temperature. Surprisingly, the corresponding field-induced circular polarization is "anomalous" in that the photoluminescence emission of the higher split energy band is stronger than that of the lower split band. This "reversed" intensity ratio originates from the combination of long electron spin relaxation time and hole negative g factor in C H3N H3Pb I3 , which are in agreement with a model based on the k.p effective-mass approximation.

  17. Pre-nuclear level of 129I in Chinese loess-paleosol sections: A search for the natural 129I level for dating in terrestrial environments

    NASA Astrophysics Data System (ADS)

    Fan, Yukun; Zhou, Weijian; Hou, Xiaolin

    2018-06-01

    Due to its long half-life (15.7 Myr), radioactive 129I has great potential for dating geologic materials as old as 100 Myr. Thus, knowing the natural level of 129I is crucial to dating applications. The initial ratio of 129I/127I in the ocean has been quantified by a number of researchers who have reached a consensus value. However, the applicability of 129I dating in the terrestrial environment remains problematic because the lack of an initial 129I/127I value. In this work, samples of loess-paleosol sections from the Chinese Loess Plateau (CLP) were analyzed for 129I/127I, aiming to provide an initial 129I/127I ratio that can be adopted for dating purposes in terrestrial environments. A value of (2.0 ± 1.0) × 10-11 for the 129I/127I ratio was found in two investigated loess-paleosol sections from Xifeng and Luochuan, China. This ratio is one order of magnitude higher than the initial value reported for the marine environment. Alteration of the natural initial 129I in the investigated samples due to the downward migration of anthropogenic 129I and by excess fissiogenic 129I from uranium was not supported. Consequently, the 129I/127I ratio measured is considered to be a pristine value, and the difference from that in the marine systems is attributed to an isotopic dilution effect.

  18. Dewetting behavior of polystyrene film filled with (C6H5C2H4NH3)2PbI4

    NASA Astrophysics Data System (ADS)

    Xue, Longjian; Cheng, Ziyong; Fu, Jun; Han, Yanchun

    2008-08-01

    The dewetting behavior of thin (about 30 nm) polystyrene (PS) films filled with different amount of (C6H5C2H4NH3)2PbI4 (PhE-PbI4) on the silicon substrate with a native oxide layer was investigated. For different additive concentrations, PhE-PbI4 showed different spatial distributions in the PS films, which had a strong influence on the film wettability, dewetting dynamics, and mechanism. With 0.5 wt % additive, PhE-PbI4 formed a noncontinuous diffusion layer, which caused a continuous hole nucleation in the film. With about 1 wt % additive, a continuous gradient distribution layer of PhE-PbI4 formed in the film, which inhibited the dewetting. When the concentration is higher (2 wt %), large PhE-PbI4 aggregates, in addition to the PhE-PbI4 continuous layer, formed in the film. These large aggregates (larger than radius of gyration of PS) migrated to the interface, resulting in the hole nucleation and eventually the complete dewetting of the film.

  19. Concentration of iodine-129 in surface seawater at subarctic and subtropical circulations in the Japan Sea

    NASA Astrophysics Data System (ADS)

    Suzuki, Takashi; Otosaka, Shigeyoshi; Togawa, Orihiko

    2013-01-01

    To investigate the migration of anthropogenic 129I in the environment, we measured 129I concentrations at both subarctic (above 40oN) and subtropical (below 40oN) circulations in the surface seawater of the Japan Sea. The averaged concentrations of stations 193, 194, 201, 206 and 210 above 200 m were (2.1 ± 0.3) × 1010 atoms/m3, (2.0 ± 0.2) × 1010 atoms/m3, (1.6 ± 0.3) × 1010 atoms/m3, (1.4 ± 0.3) × 1010 atoms/m3 and (1.7 ± 0.3) × 1010 atoms/m3, respectively. The averaged concentration at the subarctic circulation in the Japan Sea above 200 m (1.9 × 1010 atoms/m3) was higher than that in the subtropical circulation (1.5 × 1010 atoms/m3). This latitudinal distribution pattern of 129I is not consistent with those of bomb-derived radionuclides such as 14C, 90Sr and 137Cs. Taking into account latitudinal location and the total amount of releases from reprocessing plants, this discriminating latitudinal distribution of 129I in the Japan Sea would indicate that a significant amount of 129I originating from active reprocessing plants in Europe is supplied to the surface of the Japan Sea.

  20. Reconstructing surface ocean circulation with 129I time series records from corals

    USGS Publications Warehouse

    Chang, Ching-Chih; Burr, George S.; Jull, A. J. Timothy; Russell, Joellen L.; Biddulph, Dana; White, Lara; Prouty, Nancy G.; Chen, Yue-Gau; Chuan-Chou Shen,; Zhou, Weijian; Lam, Doan Dinh

    2016-01-01

    The long-lived radionuclide 129I (half-life: 15.7 × 106 yr) is well-known as a useful environmental tracer. At present, the global 129I in surface water is about 1–2 orders of magnitude higher than pre-1960 levels. Since the 1990s, anthropogenic 129I produced from industrial nuclear fuels reprocessing plants has been the primary source of 129I in marine surface waters of the Atlantic and around the globe. Here we present four coral 129I time series records from: 1) Con Dao and 2) Xisha Islands, the South China Sea, 3) Rabaul, Papua New Guinea and 4) Guam. The Con Dao coral 129I record features a sudden increase in 129I in 1959. The Xisha coral shows similar peak values for 129I as the Con Dao coral, punctuated by distinct low values, likely due to the upwelling in the central South China Sea. The Rabaul coral features much more gradual 129I increases in the 1970s, similar to a published record from the Solomon Islands. The Guam coral 129I record contains the largest measured values for any site, with two large peaks, in 1955 and 1959. Nuclear weapons testing was the primary 129I source in the Western Pacific in the latter part of the 20th Century, notably from testing in the Marshall Islands. The Guam 1955 peak and Con Dao 1959 increases are likely from the 1954 Castle Bravo test, and the Operation Hardtack I test is the most likely source of the 1959 peak observed at Guam. Radiogenic iodine found in coral was carried primarily through surface ocean currents. The coral 129I time series data provide a broad picture of the surface distribution and depth penetration of 129I in the Pacific Ocean over the past 60 years.

  1. π-stacking and C-X...D (X = H, NO2; D = O, π) interactions in the crystal network of both C-H...N and π-stacked dimers of 1,2-bis(4-bromophenyl)-1H-benzimidazole and 2-(4-bromophenyl)-1-(4-nitrophenyl)-1H-benzimidazole.

    PubMed

    González-Padilla, Jazmin E; Rosales-Hernández, Martha C; Padilla-Martínez, Itzia I; García-Báez, Efren V; Rojas-Lima, Susana; Salazar-Pereda, Veronica

    2014-01-01

    Molecules of 1,2-bis(4-bromophenyl)-1H-benzimidazole, C19H12Br2N2, (I), and 2-(4-bromophenyl)-1-(4-nitrophenyl)-1H-benzimidazole, C19H12BrN3O2, (II), are arranged in dimeric units through C-H...N and parallel-displaced π-stacking interactions favoured by the appropriate disposition of N- and C-bonded phenyl rings with respect to the mean benzimidazole plane. The molecular packing of the dimers of (I) and (II) arises by the concurrence of a diverse set of weak intermolecular C-X...D (X = H, NO2; D = O, π) interactions.

  2. Cocrystal assembled by 1,4-diiodotetrafluorobenzene and phenothiazine based on C-I...π/N/S halogen bond and other assisting interactions.

    PubMed

    Wang, Hui; Jin, Wei Jun

    2017-04-01

    The halogen-bonded cocrystal of 1,4-diiodotetrafluorobenzene (1,4-DITFB) with the butterfly-shape non-planar heterocyclic compound phenothiazine (PHT) was successfully assembled by the conventional solution-based method. X-ray single-crystal diffraction analysis reveals a 3:2 stoichiometric ratio for the cocrystal (1,4-DITFB/PHT), and the cocrystal structure is constructed via C-I...π, C-I...N and C-I...S halogen bonds as well as other assisting interactions (e.g. C-H...F/S hydrogen bond, C-H...H-C and C-F...F-C bonds). The small shift of the 1,4-DITFB vibrational band to lower frequencies in FT-IR and Raman spectroscopies provide evidence to confirm the existence of the halogen bond. In addition, the non-planarity of the PHT molecule in the cocrystal results in PHT emitting weak phosphorescence and relatively strong delayed fluorescence. Thus, a wide range of delayed fluorescence and weak phosphorescence could play a significant role in selecting a proper π-conjugated system to engineer functional cocrystal and luminescent materials by halogen bonds.

  3. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    NASA Astrophysics Data System (ADS)

    Atkinson, A. P.; Cartwright, I.; Gilfedder, B. S.; Cendón, D. I.; Unland, N. P.; Hofmann, H.

    2014-12-01

    Knowledge of groundwater residence times and recharge locations is vital to the sustainable management of groundwater resources. Here we investigate groundwater residence times and patterns of recharge in the Gellibrand Valley, southeast Australia, where outcropping aquifer sediments of the Eastern View Formation form an "aquifer window" that may receive diffuse recharge from rainfall and recharge from the Gellibrand River. To determine recharge patterns and groundwater flow paths, environmental isotopes (3H, 14C, δ13C, δ18O, δ2H) are used in conjunction with groundwater geochemistry and continuous monitoring of groundwater elevation and electrical conductivity. The water table fluctuates by 0.9 to 3.7 m annually, implying recharge rates of 90 and 372 mm yr-1. However, residence times of shallow (11 to 29 m) groundwater determined by 14C are between 100 and 10 000 years, 3H activities are negligible in most of the groundwater, and groundwater electrical conductivity remains constant over the period of study. Deeper groundwater with older 14C ages has lower δ18O values than younger, shallower groundwater, which is consistent with it being derived from greater altitudes. The combined geochemistry data indicate that local recharge from precipitation within the valley occurs through the aquifer window, however much of the groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High. The Gellibrand Valley is a regional discharge zone with upward head gradients that limits local recharge to the upper 10 m of the aquifer. Additionally, the groundwater head gradients adjacent to the Gellibrand River are generally upwards, implying that it does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10

  4. 1,4-Iron Migration for Expedient Allene Annulations through Iron-Catalyzed C-H/N-H/C-O/C-H Functionalizations.

    PubMed

    Mo, Jiayu; Müller, Thomas; Oliveira, João C A; Ackermann, Lutz

    2018-06-25

    C-H activation bears great potential for enabling sustainable molecular syntheses in a step- and atom-economical manner, with major advances having been realized with precious 4d and 5d transition metals. In contrast, we employed earth abundant, nontoxic iron catalysts for versatile allene annulations through a unique C-H/N-H/C-O/C-H functionalization sequence. The powerful iron catalysis occurred under external-oxidant-free conditions even at room temperature, while detailed mechanistic studies revealed an unprecedented 1,4-iron migration regime for facile C-H activations. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Condensation Time of the Solar Nebula from Extinct 129I in Primitive Meteorites

    PubMed Central

    Lewis, Roy S.; Anders, Edward

    1975-01-01

    Mineral separates from five carbonaceous chondrites were dated by extinct 16 million year 129I, in an attempt to establish the condensation time of the solar nebula. Two Fe3O4 or Fe3O4-FeS samples from the Murchison and Orgueil meteorites are older than any other material dated thus far, and apparently formed within 2 × 105 years of each other. The great age, close isochronism, and primitive nature of the samples suggest that the event recorded was the condensation stage of the solar nebula. It provides a suitable zero point for the chronology of the early solar system. The 129I/127I ratio during condensation of the nebula was (1.46 ± 0.04) × 10-4. The recrystallized C4 chondrite Karoonda began to retain 129Xe 1.8 ± 0.5 million years after the above event. This short cooling time implies rapid aceretion (≤1 million years) and a shallow origin (≤10 km) below the surface of its parent body. Images PMID:16592213

  6. Maltodextrin and sucrose preferences in sweet-sensitive (C57BL/6J) and subsensitive (129P3/J) mice revisited.

    PubMed

    Ackroff, Karen; Sclafani, Anthony

    2016-10-15

    Mice are attracted to the tastes of sugar and maltodextrin solutions. Sugar taste is mediated by the T1R2/T1R3 sweet taste receptor, while maltodextrin taste is dependent upon a different as yet unidentified receptor. In a prior study sweet-sensitive C57BL/6J (B6) mice displayed similar preferences for sucrose and maltodextrin solutions in 24-h saccharide vs. water choice tests that exceeded those of sweet-subsensitive 129P3/J (129) mice. In a subsequent experiment reported here, sucrose and maltodextrin (Polycose) preference and acceptance were compared in the two strains in saccharide vs. saccharide choice tests with isocaloric concentrations (0.5-32%). The 129 mice displayed significantly greater maltodextrin preferences than B6 mice at mid-range concentrations (2-8%), while the mice displayed an opposite preference profile at the highest concentration (32%). As in prior studies, 129 mice consumed less total saccharide than B6 mice at lower concentrations. These findings show that the conclusions reached from tastant vs. water tests may differ from those pitting one tastant against another. The increased sucrose preference and intake of B6 mice, relative to 129 mice, is consistent with their sweet-sensitive phenotype. Copyright © 2016 Elsevier Inc. All rights reserved.

  7. Nqrs Data for H6I3InO12 [I3InO9·3(H2O)] (Subst. No. 2289)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume B 'Substances Containing C10H16 … Zn' of Volume 48 'Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III 'Condensed Matter'. It contains an extract of Section '3.2 Data tables' of the Chapter '3 Nuclear quadrupole resonance data' providing the NQRS data for H6I3InO12 [I3InO9·3(H2O)] (Subst. No. 2289)

  8. Reconstructing surface ocean circulation with 129I time series records from corals.

    PubMed

    Chang, Ching-Chih; Burr, George S; Jull, A J Timothy; Russell, Joellen L; Biddulph, Dana; White, Lara; Prouty, Nancy G; Chen, Yue-Gau; Shen, Chuan-Chou; Zhou, Weijian; Lam, Doan Dinh

    2016-12-01

    The long-lived radionuclide 129 I (half-life: 15.7 × 10 6  yr) is well-known as a useful environmental tracer. At present, the global 129 I in surface water is about 1-2 orders of magnitude higher than pre-1960 levels. Since the 1990s, anthropogenic 129 I produced from industrial nuclear fuels reprocessing plants has been the primary source of 129 I in marine surface waters of the Atlantic and around the globe. Here we present four coral 129 I time series records from: 1) Con Dao and 2) Xisha Islands, the South China Sea, 3) Rabaul, Papua New Guinea and 4) Guam. The Con Dao coral 129 I record features a sudden increase in 129 I in 1959. The Xisha coral shows similar peak values for 129 I as the Con Dao coral, punctuated by distinct low values, likely due to the upwelling in the central South China Sea. The Rabaul coral features much more gradual 129 I increases in the 1970s, similar to a published record from the Solomon Islands. The Guam coral 129 I record contains the largest measured values for any site, with two large peaks, in 1955 and 1959. Nuclear weapons testing was the primary 129 I source in the Western Pacific in the latter part of the 20th Century, notably from testing in the Marshall Islands. The Guam 1955 peak and Con Dao 1959 increases are likely from the 1954 Castle Bravo test, and the Operation Hardtack I test is the most likely source of the 1959 peak observed at Guam. Radiogenic iodine found in coral was carried primarily through surface ocean currents. The coral 129 I time series data provide a broad picture of the surface distribution and depth penetration of 129 I in the Pacific Ocean over the past 60 years. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.

  9. Using 14C and 3H to understand groundwater flow and recharge in an aquifer window

    NASA Astrophysics Data System (ADS)

    Atkinson, A. P.; Cartwright, I.; Gilfedder, B. S.; Cendón, D. I.; Unland, N. P.; Hofmann, H.

    2014-06-01

    Knowledge of groundwater residence times and recharge locations are vital to the sustainable management of groundwater resources. Here we investigate groundwater residence times and patterns of recharge in the Gellibrand Valley, southeast Australia, where outcropping aquifer sediments of the Eastern View Formation form an "aquifer window" that may receive diffuse recharge and recharge from the Gellibrand River. To determine recharge patterns and groundwater flowpaths, environmental isotopes (3H, 14C, δ13C, δ18O, δ2H) are used in conjunction with groundwater geochemistry and continuous monitoring of groundwater elevation and electrical conductivity. Despite the water table fluctuating by 0.9-3.7 m annually producing estimated recharge rates of 90 and 372 mm yr-1, residence times of shallow (11-29 m) groundwater determined by 14C ages are between 100 and 10 000 years. 3H activities are negligible in most of the groundwater and groundwater electrical conductivity in individual areas remains constant over the period of study. Although diffuse local recharge is evident, the depth to which it penetrates is limited to the upper 10 m of the aquifer. Rather, groundwater in the Gellibrand Valley predominantly originates from the regional recharge zone, the Barongarook High, and acts as a regional discharge zone where upward head gradients are maintained annually, limiting local recharge. Additionally, the Gellibrand River does not recharge the surrounding groundwater and has limited bank storage. 14C ages and Cl concentrations are well correlated and Cl concentrations may be used to provide a first-order estimate of groundwater residence times. Progressively lower chloride concentrations from 10 000 years BP to the present day are interpreted to indicate an increase in recharge rates on the Barongarook High.

  10. Uptake, metabolism and excretion of orally and intravenously administered, 14C- and 3H-labeled N-acetylneuraminic acid mixture in the mouse and rat.

    PubMed

    Nöhle, U; Schauer, R

    1981-11-01

    N-Acetyl-D-[2-14C,9-3H]neuraminic acid, enzymically prepared from sodium [2-14C]-pyruvate and N-acetyl-D-[6-3H]mannosamine by N-acetylneuraminate lyase in 75% yield, was orally administered to 20 day old fasted mice. 90% of the administered neuraminic acid was absorbed from the intestine in the course of 4 h, at a rate depending on the retention time of neuraminic acid in the intestine and the mental conditions of the animals. Between 60 and 90% of the neuraminic acid was excreted in the urine without chemical alteration within the first 6 h. Four hours after administration 10% of the 3H- and 1.3% of the 14C-radioactivity were recovered in the whole blood and in liver, spleen, kidney and brain. After 3 days 0.5% of 3H- and 0.01% of 14C-radioactivity still remained in these tissues. The discrepancy of the 14C-amount relative to the 3H-quantity was accounted for by exhaled 14CO2. After intravenous injection of N-acetylneuraminic acid into rats, 90% of the radioactivity corresponding to the original substance was excreted in the urine within 10 min. Four hours after administration only 5% of the applied 3H- and 1.2% of the 14C-radioactivity were left in the blood and in liver, spleen, kidney and brain. The experiments show that neither orally nor intravenously applied N-acetylneuraminic acid can penetrate cell membranes to a large extent, with the exception of the intestine. The isotopic ratio and N-acetylneuraminate lyase activity suggest that the small amount of the neuraminic acid retained in tissues was largely cleaved by the lyase, followed by metabolism of the reaction products. It may be concluded from these observations that neuraminic acid occurring in food cannot directly be used for the biosynthesis of glycoconjugates on a large scale.

  11. One-dimensional Cu(II) coordination polymers containing C2h-symmetric 1,1':4',1''-terphenyl-3,3'-dicarboxylate linkers.

    PubMed

    Kim, Hyun Chul; Gu, Ja Min; Huh, Seong; Yo, Chul Hyun; Kim, Youngmee

    2015-10-01

    Two new one-dimensional Cu(II) coordination polymers (CPs) containing the C2h-symmetric terphenyl-based dicarboxylate linker 1,1':4',1''-terphenyl-3,3'-dicarboxylate (3,3'-TPDC), namely catena-poly[[bis(dimethylamine-κN)copper(II)]-μ-1,1':4',1''-terphenyl-3,3'-dicarboxylato-κ(4)O,O':O'':O'''] monohydrate], {[Cu(C20H12O4)(C2H7N)2]·H2O}n, (I), and catena-poly[[aquabis(dimethylamine-κN)copper(II)]-μ-1,1':4',1''-terphenyl-3,3'-dicarboxylato-κ(2)O(3):O(3')] monohydrate], {[Cu(C20H12O4)(C2H7N)2(H2O)]·H2O}n, (II), were both obtained from two different methods of preparation: one reaction was performed in the presence of 1,4-diazabicyclo[2.2.2]octane (DABCO) as a potential pillar ligand and the other was carried out in the absence of the DABCO pillar. Both reactions afforded crystals of different colours, i.e. violet plates for (I) and blue needles for (II), both of which were analysed by X-ray crystallography. The 3,3'-TPDC bridging ligands coordinate the Cu(II) ions in asymmetric chelating modes in (I) and in monodenate binding modes in (II), forming one-dimensional chains in each case. Both coordination polymers contain two coordinated dimethylamine ligands in mutually trans positions, and there is an additional aqua ligand in (II). The solvent water molecules are involved in hydrogen bonds between the one-dimensional coordination polymer chains, forming a two-dimensional network in (I) and a three-dimensional network in (II).

  12. Involvement of conformational isomerism in the complexity of the crystal network of 1-(4-nitrophenyl)-1H-1,3-benzimidazole derivatives driven by C-H...A (A = NO2, Npy and π) and orthogonal Npy...NO2 and ONO...Csp2 interactions.

    PubMed

    García-Aranda, Mónica I; Gómez-Castro, Carlos Z; García-Báez, Efrén V; Gómez, Yolanda Gómez Y; Castrejón-Flores, José L; Padilla-Martínez, Itzia I

    2018-04-01

    A detailed structural analysis of the benzimidazole nitroarenes 1-(4-nitrophenyl)-1H-1,3-benzimidazole, C 13 H 9 N 3 O 2 , (I), 1-(4-nitrophenyl)-2-phenyl-1H-1,3-benzimidazole, C 19 H 13 N 3 O 2 , (II), and 2-(3-methylphenyl)-1-(4-nitrophenyl)-1H-1,3-benzimidazole, C 20 H 15 N 3 O 2 , (III), has been performed. They are nonplanar structures whose crystal arrangement is governed by Csp 2 -H...A (A = NO 2 , N py and π) hydrogen bonding. The inherent complexity of the supramolecular arrangements of compounds (I) (Z' = 2) and (II) (Z' = 4) into tapes, helices and sheets is the result of the additional participation of π-π NO2 and n-π* (n = O and N py ; π* = Csp 2 and N NO2 ) interactions that contribute to the stabilization of the equi-energetic conformations adopted by each of the independent molecules in the asymmetric unit. In contrast, compound (III) (Z' = 1) is self-paired, probably due to the effect of the steric demand of the methyl group on the crystal packing. Theoretical ab initio calculations confirmed that the presence of the arene ring at the benzimidazole 2-position increases the rotational barrier of the nitrobenzene ring and also supports the electrostatic nature of the orthogonal ONO...Csp 2 and N py ...NO 2 interactions.

  13. Sweetener preference of C57BL/6ByJ and 129P3/J mice

    PubMed Central

    Bachmanov, Alexander A.; Tordoff, Michael G.; Beauchamp, Gary K.

    2013-01-01

    Previous studies have shown large differences in taste responses to several sweeteners between mice from the C57BL/6ByJ (B6) and 129P3/J (129) inbred strains. The goal of this study was to compare behavioral responses of the B6 and 129 mice to a wider variety of sweeteners. Seventeen sweeteners were tested using two-bottle preference tests with water. Three main patterns of strain differences were evident. First, sucrose, maltose, saccharin, acesulfame, sucralose and SC-45647 were preferred by both strains, but the B6 mice had lower preference thresholds and higher solution intakes. Second, the amino acids D-phenylalanine, D-tryptophan, L-proline and glycine were highly preferred by the B6 mice, but not by the 129 mice. Third, glycyrrhizic acid, neohesperidin dihydrochalcone, thaumatin and cyclamate did not evoke strong preferences in either strain. Aspartame was neutral to all 129 mice and some B6 mice, but other B6 mice strongly preferred it. Thus, compared with the 129 mice, the B6 mice had higher preferences for sugars, sweet-tasting amino acids and several but not all non-caloric sweeteners. Glycyrrhizic acid, neohesperidin, thaumatin and cyclamate are not palatable to B6 or 129 mice. PMID:11555485

  14. H i Absorption in the Steep-Spectrum Superluminal Quasar 3C 216.

    PubMed

    Pihlström; Vermeulen; Taylor; Conway

    1999-11-01

    The search for H i absorption in strong compact steep-spectrum sources is a natural way to probe the neutral gas contents in young radio sources. In turn, this may provide information about the evolution of powerful radio sources. The recently improved capabilities of the Westerbork Synthesis Radio Telescope have made it possible to detect a 0.31% (19 mJy) deep neutral atomic hydrogen absorption line associated with the steep-spectrum superluminal quasar 3C 216. The redshift (z=0.67) of the source shifts the frequency of the 21 cm line down to the ultra-high-frequency (UHF) band (850 MHz). The exact location of the H i-absorbing gas remains to be determined by spectral line VLBI observations at 850 MHz. We cannot exclude that the gas might be extended on galactic scales, but we think it is more likely to be located in the central kiloparsec. Constraints from the lack of X-ray absorption probably rule out obscuration of the core region, and we argue that the most plausible site for the H i absorption is in the jet-cloud interaction observed in this source.

  15. The H+n-C5H12/n-C6H14H2(v',j')+C5H11/C6H13 reactions: State-to-state dynamics and models of energy disposal

    NASA Astrophysics Data System (ADS)

    Picconatto, Carl A.; Srivastava, Abneesh; Valentini, James J.

    2001-03-01

    The rovibrational state distributions for the H2 product of the H+n-C5H12/n-C6H14H2+C5H11/C6H13 reactions at 1.6 eV collision energy are reported. The results are compared to measurements made on the kinematically and energetically similar H+RH→H2+R (RH=CH4, C2H6, and C3H8) reactions as well as the atom-diatom reactions H+HX→H2+X(HX=HCl, HBr). For the title reactions, as for all the comparison reactions, the product appears in few of the energetically accessible states. This is interpreted as the result of a kinematic constraint on the product translational energy. Characteristic of the H+RH reactions we have previously studied, the title reactions show increasing rotational excitation of the H2 product with increasing vibrational excitation of it, a correlation that gets stronger as the size of the alkane increases. Trends and variations in the product energy disposal are analyzed and explained by a localized reaction model. This model predicates a truncation of the opacity function due to competing reactive sites in the polyatomic alkane reactant, and a relaxation of the otherwise tight coupling of energy and angular momentum conservation, because the polyatomic alkyl radical product is a sink for angular momentum.

  16. Radical-molecule reaction C3H+H2O: a mechanistic study.

    PubMed

    Dong, Hao; Ding, Yi-Hong; Sun, Chia-Chung

    2005-02-08

    Despite the importance of the C(3)H radical in both combustion and interstellar space, the reactions of C(3)H toward stable molecules have never been studied. In this paper, we report our detailed mechanistic study on the radical-molecule reaction C(3)H+H(2)O at the Becke's three parameter Lee-Yang-Parr-B3LYP6-311G(d,p) and coupled cluster with single, double, and triple excitations-CCSD(T)6-311G(2d,p) (single-point) levels. It is shown that the C(3)H+H(2)O reaction initially favors formation of the carbene-insertion intermediates HCCCHOH (1a,1b) rather than the direct H- or OH-abstraction process. Subsequently, the isomers (1a,1b) can undergo a direct H- extrusion to form the well-known product propynal HCCCHO (P(5)). Highly competitively, (1a,1b) can take the successive 1,4- and 1,2-H-shift interconversion to isomer H(2)CCCHO(2a,2b) and then to isomer H(2)CCHCO(3a,3b), which can finally take a direct C-C bond cleavage to give product C(2)H(3) and CO (P(1)). The other products are kinetically much less feasible. With the overall entrance barrier 10.6 kcal/mol, the title reaction can be important in postburning processes. Particularly, our calculations suggest that the title reaction may play a role in the formation of the intriguing interstellar molecule, propynal HCCCHO. The calculated results will also be useful for the analogous C(3)H reactions such as with ammonia and alkanes.

  17. The atmospheric transport of iodine-129 from Fukushima to British Columbia, Canada and its deposition and transport into groundwater

    NASA Astrophysics Data System (ADS)

    Herod, Matt N.; Suchy, Martin; Cornett, R. Jack; Kieser, W. E.; Clark, Ian D.; Graham, Gwyn

    2015-12-01

    The Fukushima-Daiichi nuclear accident (FDNA) released iodine-129 (15.7 million year half-life) and other fission product radionuclides into the environment in the spring and summer of 2011. 129I is recognized as a useful tracer for the short-lived radiohazard 131I, which has a mobile geochemical behavior with potential to contaminate water resources. To trace 129I released by the FDNA reaching Canada, pre-accident and post-accident rain samples collected in Vancouver, on Saturna Island and from the National Atmospheric Deposition Program in Washington State were measured. Groundwater from the Abbotsford-Sumas Aquifer was sampled to determine the fate of 129I that infiltrates below the root zone. Modeling of vadose zone transport was performed to constrain the travel time and retardation of 129I. The mean pre-accident 129I concentration in rain was 31 × 106 atoms/L (n = 4). Immediately following the FDNA, 129I values increased to 211 × 106 atoms/L and quickly returned to near-background levels. However, pulses of elevated 129I continued for several months. The increases in 129I concentrations from both Vancouver and Saturna Island were synchronized, and occurred directly after the initial release from the FDNA. The 129I in shallow (3H/3He age <1.4 years) Wassenaar et al. (2006) groundwater showed measurable variability through March 2013 with an average of 3.2 × 106 atoms/L (n = 32) that was coincident with modeled travel times for Fukushima 129I. The groundwater response and the modeling results suggest that 129I was partially attenuated in soil, which is consistent with its geochemical behavior; however, we conclude that the measured variability may be due to Fukushima 129I entering groundwater.

  18. Synthesis and characterization of 3-ketohexadecanoic acid-1-14-C, DL-3-hydroxyhexadecanoic acid-1-14-C, and trans-2-hexadecenoic acid-1-14-C.

    PubMed

    Jones, J A; Blecher, M

    1966-05-01

    The chemical synthesis and characterization of three intermediates in the Beta oxidation of palmitic acid-1-(14)C by rat liver mitochondria, namely, 3-ketohexadecanoic acid-1-(14)C, DL-3-hydroxyhexadecanoic acid-1-(14)C, and trans-2-hexadecenoic acid-1-(14)C, are described.

  19. The {sup 129}Iodine bomb pulse recorded in Mississippi River Delta sediments: Results from isotopes of I, Pu, Cs, Pb, and C

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

    Oktay, S.D.; Santschi, P.H.; Moran, J.E.

    2000-03-01

    Anthropogenic sources from nuclear reprocessing discharges and bomb test fallout have completely overwhelmed the natural signal on the surface of the earth in the last 50 years. However, the transfer functions in and out of environmental compartments are not well known due to temporal variations in the sources of {sup 129}I and to a lack of knowledge regarding the forms of iodine. From a vertical profile of {sup 129}I/{sup 127}I ratios in sediments located in the Mississippi Delta region in approximately 60 meters water depth, the {sup 129}I input function to this region was reconstructed. Dates in the core weremore » assigned based on the plutonium peak at 20 cm depth (assumed to have been deposited in 1963) and the excess {sup 210}Pb profile in the same depth interval, and below that, based on the steadily decreasing {sup 240}Pu/{sup 239}Pu ratios from a ratio of 0.18 at 22 cm to 0.05 at 57 cm depth, the 1953 horizon. Atom ratios of {sup 129}I/{sup 137}I Cs, decay corrected to 1962, the year of maximum radionuclide production, are about 0.3, very close to the production ratios of about 0.2 during atomic bomb tests. This evidence, combined with other observations, strongly suggests that {sup 129}I in Mississippi River Delta sediments originates from atomic bomb fallout eroded from soils of the Mississippi River drainage basin, with little alteration of the isotopic ratios during transport from watershed to coastal deposits. Based on these observations and on laboratory evidence, the authors propose a conceptual model which explains this correspondence and the low {sup 129}I/{sup 127}I ratios. Differences in mobilities of the different chemical forms of {sup 129}I and {sup 127}I, as well as the variances in chemical forms of {sup 129}I from nuclear bomb fallout versus nuclear fuel reprocessing, are proposed to have created such a correspondence between I-isotope ratios and bomb fallout nuclides, without revealing recent inputs from nuclear fuel reprocessing

  20. Ab initio study of C + H3+ reactions

    NASA Technical Reports Server (NTRS)

    Talbi, D.; DeFrees, D. J.

    1991-01-01

    The reaction C + H3+ --> CH(+) + H2 is frequently used in models of dense interstellar cloud chemistry with the assumption that it is fast, i.e. there are no potential energy barriers inhibiting it. Ab initio molecular orbital study of the triplet CH3+ potential energy surface (triplet because the reactant carbon atom is a ground state triplet) supports this hypothesis. The reaction product is 3 pi CH+; the reaction is to exothermic even though the product is not in its electronic ground state. No path has been found on the potential energy surface for C + H3+ --> CH2(+) + H reaction.

  1. The composition of Saturn's atmosphere at northern temperate latitudes from Voyager IRIS spectra - NH3, PH3, C2H2, C2H6, CH3D, CH4, and the Saturnian D/H isotopic ratio

    NASA Technical Reports Server (NTRS)

    Courtin, R.; Gautier, D.; Marten, A.; Bezard, B.; Hanel, R.

    1984-01-01

    The vertical distributions and mixing ratios of minor constituents in the northern hemisphere of Saturn are investigated. Results are obtained for NH3, PH3, C2H2, C2H6, CH3D, and CH4; the D/H ratio is obtained from the CH4 and CH3D abundances. The NH3 mixing ratio in the upper atmosphere is found to be compatible with the saturated partial pressure. The inferred PH3/H2 ratio of 1.4 + or - 0.8 x 10 to the -6th is higher than the value derived from the solar P/H ratio. The stratospheric C2H2/H2 and C2H6/H2 ratios are, respectively, 2.1 + or - 1.4 x 10 to the -7th and 3.0 + or - 1.1 x 10 to the -6th; the latter decreases sharply below the 20-50 mbar level. The results for CH3D/H2 and CH4/H2 imply an enrichment of Saturn's upper atmosphere in carbon by a factor of at least three over the solar abundance. The interpretation of two NH3 lines in the five-micron window suggests a NH3/H2 ratio at the two bar level below the solar value.

  2. Anthropogenic 129I in the North Pacific, Bering and Chukchi Seas, and Arctic Ocean in 2012-2013

    NASA Astrophysics Data System (ADS)

    Nagai, H.; Hasegawa, A.; Yamagata, T.; Kumamoto, Y.; Nishino, S.; Matsuzaki, H.

    2015-10-01

    Most of anthropogenic 129I in marine environment are due to discharge from the nuclear fuel reprocessing facilities at Sellafield (U.K.) and La Hague (France) for past few decades. The discharge raised 129I concentration in seawaters in the North Atlantic and Arctic Oceans to more than 109 atoms L-1, which is two orders of magnitude higher than that in other region. Recently, in March 2011, a large quantity of 129I was released into the western North Pacific due to the Fukushima Daiichi Nuclear Power Plant (F1NPP) accident. To evaluate the influence of these events, we have measured 129I concentration in seawaters in the northern North Pacific Ocean, Bering and Chukchi Seas, and Arctic Ocean in 2012-2013. The 129I concentrations were 1.0-1.8 × 107 atoms L-1 in the surface waters in the vicinity of 47°N 150°E-130°W North Pacific Ocean, Bering Sea, and Chukchi Sea (<74°N), which are equal to or lower than the 129I concentration level in surface water in the North Pacific Ocean before the F1NPP accident. The vertical profiles in the North Pacific were almost same as that observed in the western North Pacific before the F1NPP accident. The 129I distribution in seawater in the North Pacific to the Chukchi Sea revealed no significant increase of 129I concentration caused by the F1NPP accident. The 129I concentrations were 13-14 × 107 atoms L-1 in surface waters and 80 × 107 atoms L-1 at depths of 300 and 800 m in the Arctic Ocean.

  3. 78 FR 11907 - Notice of Forthcoming Workshop To Discuss Revisions to NUREG/BR-0204, Rev. 2 “Instructions for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-20

    ... would like the NRC to update NUREG/BR-0204 to address the manifesting of Technecium-99 (Tc-99), Carbon-14 (C-14), Tritium (H-3), and Iodine-129 (I-129) to minimize over-estimation of activity. These... uniform manifest for the waste shipment, ``[t]he activity of each of the radionuclides H-3, C-14, Tc-99...

  4. Structure of C 14 and B 14 from the C 14 , 15 ( d , He 3 ) B 13 , 14 reactions

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

    Bedoor, S.; Wuosmaa, A. H.; Albers, M.

    We have studied the C-14,C-15(d,He-3)B-13,B-14 proton-removing reactions in inverse kinematics. The (d,He-3) reaction probes the proton occupation of the target ground state, and also provides spectroscopic information about the final states in B-13,B-14. The experiments were performed using C-14,C-15 beams from the ATLAS accelerator at Argonne National Laboratory. The reaction products were analyzed with the HELIOS device. Angular distributions were obtained for transitions from both reactions. The C-14-beam data reveal transitions to excited states in B-13 that suggest configurations with protons outside the pi(0p(3/2)) orbital, and some possibility of proton cross-shell 0p-1s0d excitations, in the C-14 ground state. The C-15-beammore » data confirm the existence of a broad 2(-) excited state in B-14. The experimental data are compared to the results of shell-model calculations.« less

  5. Gold(I) Complexes with N-Donor Ligands. 2.(1) Reactions of Ammonium Salts with [Au(acac-kappaC(2))(PR(3))] To Give [Au(NH(3))L](+), [(AuL)(2)(&mgr;(2)-NH(2))](+), [(AuL)(4)(&mgr;(4)-N)](+), or [(AuL)(3)(&mgr;(3)-O)](+). A New and Facile Synthesis of [Au(NH(3))(2)](+) Salts. Crystal Structure of [{AuP(C(6)H(4)OMe-4)(3)}(3)(&mgr;(3)-O)]CF(3)SO(3).

    PubMed

    Vicente, José; Chicote, María-Teresa; Guerrero, Rita; Jones, Peter G.; Ramírez De Arellano, M. Carmen

    1997-09-24

    The complexes [Au(acac-kappaC(2))(PR(3))] (acac = acetylacetonate, R = Ph, C(6)H(4)OMe-4) react with (NH(4))ClO(4) to give amminegold(I), [Au(NH(3))(PR(3))]ClO(4), amidogold(I), [(AuPR(3))(2)(&mgr;(2)-NH(2))]ClO(4), or nitridogold(I), [(AuPR(3))(4)(&mgr;(4)-N)]ClO(4), complexes, depending on the reaction conditions. Similarly, [Au(acac-kappaC(2))(PPh(3))] reacts with (NH(3)R')OTf (OTf = CF(3)SO(3)) (1:1) or with [H(3)N(CH(2))(2)NH(2)]OTf (1:1) to give (amine)gold(I) complexes [Au(NH(2)R')(PPh(3))]OTf (R' = Me, C(6)H(4)NO(2)-4) or [(AuPPh(3))(2){&mgr;(2)-H(2)N(CH(2))(2)NH(2)}](OTf)(2), respectively. The ammonium salts (NH(2)R'(2))OTf (R' = Et, Ph) react with [Au(acac-kappaC(2))(PR(3))] (R = Ph, C(6)H(4)OMe-4) (1:2) to give, after hydrolysis, the oxonium salts [(AuPR(3))(3)(&mgr;(3)-O)]OTf (R = Ph, C(6)H(4)OMe-4). When NH(3) is bubbled through a solution of [AuCl(tht)] (tht = tetrahydrothiophene), the complex [Au(NH(3))(2)]Cl precipitates. Addition of [Au(NH(3))(2)]Cl to a solution of AgClO(4) or TlOTf leads to the isolation of [Au(NH(3))(2)]ClO(4) or [Au(NH(3))(2)]OTf, respectively. The crystal structure of [(AuPR(3))(3)(&mgr;(3)-O)]OTf.Me(2)CO (R = C(6)H(4)OMe-4) has been determined: triclinic, space group P&onemacr;, a = 14.884(3) Å, b = 15.828(3) Å, c = 16.061(3) Å, alpha = 83.39(3) degrees, beta = 86.28(3) degrees, gamma = 65.54(3) degrees, R1 (wR2) = 0.0370 (0.0788). The [(AuPR(3))(3)(&mgr;(3)-O)](+) cation shows an essentially trigonal pyramidal array of three gold atoms and one oxygen atom with O-Au-P bond angles of ca. 175 degrees and Au.Au contacts in the range 2.9585(7)-3.0505(14) Å. These cations are linked into centrosymmetric dimers through two short Au.Au [2.9585(7), 3.0919(9) Å] contacts. The gold atoms of the dimer form a six-membered ring with a chair conformation.

  6. A 60-year record of 129I in Taal Lake sediments (Philippines): Influence of human nuclear activities at low latitude regions.

    PubMed

    Zhang, Luyuan; Hou, Xiaolin; Li, Hong-Chun; Xu, Xiaomei

    2018-02-01

    The influence of human nuclear activities on environmental radioactivity is not well known at low latitude regions that are distant from nuclear test sites and nuclear facilities. A sediment core collected from Taal Lake in the central Philippines was analyzed for 129 I and 127 I to investigate this influence in a low-latitude terrestrial system. A baseline of 129 I/ 127 I atomic ratios was established at (2.04-5.14) × 10 -12 in the pre-nuclear era in this region. Controlled by the northeasterly equatorial trade winds, increased 129 I/ 127 I ratios of (20.1-69.3) × 10 -12 suggest that atmospheric nuclear weapons tests at the Pacific Proving Grounds in the central Pacific Ocean was the major source of 129 I in the sediment during 1956-1962. The 129 I/ 127 I ratios, up to 157.5 × 10 -12 after 1964, indicate a strong influence by European nuclear fuel reprocessing plants. The East Asian Winter Monsoon is found to be the dominant driving force in the atmospheric dispersion of radioactive iodine ( 129 I) from the European nuclear fuel reprocessing plants to Southeast Asia, which is also important for dispersion of other airborne pollutants from the middle-high to low latitude regions. A significant 129 I/ 127 I peak at 42.8 cm in the Taal Lake core appears to be the signal of the Chernobyl accident in 1986. In addition, volcanic activities are reflected in the iodine isotope profiles in the sediment core, suggesting the potential of using iodine isotopes as an indicator of volcanic eruptions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Disposition of [14C]N,N-dimethyl-p-toluidine in F344 rats and B6C3F1 mice.

    PubMed

    Dix, Kelly J; Ghanbari, Katayoon; Hedtke-Weber, Briana M

    2007-05-15

    N,N-Dimethyl-p-toluidine (DMPT) is used as a polymerization accelerator, in industrial glues, and as an intermediate in dye and pesticide synthesis. There is potential for human exposure to DMPT. The disposition of oral and intravenous (i.v.) doses of [14C]DMPT in F344 rats and B6C3F1 mice was investigated. A single i.v. (2.5 mg/kg) or oral (2.5, 25, or 250 mg/kg) dose of [14C]DMPT (1-25 microCi) was administered in an aqueous vehicle to male rats and mice. The 25-mg/kg oral dose was administered to females to investigate possible gender differences in disposition. However, no striking gender differences were observed. Since toxicity studies conducted elsewhere used a corn oil vehicle, the 250-mg/kg oral dose also was administered in corn oil to male rats; disposition was not dependent on vehicle. Excreta (through 24 h) and tissues collected at sacrifice were analyzed for total radioactivity. Dose-dependent differences in toxicity and disposition were observed. Toxicity at the 250-mg/kg oral dose to male mice was consistent with acute renal failure. At the same dose, male rats exhibited clinical signs of toxicity through 12 h but were clinically normal by 24 h. At lower oral doses, [14C]DMPT-derived radioactivity was well absorbed and rapidly excreted, primarily in urine.

  8. Expansion of antimonato polyoxovanadates with transition metal complexes: (Co(N3C5H15)2)2[{Co(N3C5H15)2}V15Sb6O42(H2O)]·5H2O and (Ni(N3C5H15)2)2[{Ni(N3C5H15)2}V15Sb6O42(H2O)]·8H2O.

    PubMed

    Antonova, Elena; Näther, Christian; Kögerler, Paul; Bensch, Wolfgang

    2012-02-20

    Two new polyoxovanadates (Co(N(3)C(5)H(15))(2))(2)[{Co(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·5H(2)O (1) and (Ni(N(3)C(5)H(15))(2))(2)[{Ni(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)]·8H(2)O (2) (N(3)C(5)H(15) = N-(2-aminoethyl)-1,3-propanediamine) were synthesized under solvothermal conditions and structurally characterized. In both structures the [V(15)Sb(6)O(42)(H(2)O)](6-) shell displays the main structural motif, which is strongly related to the {V(18)O(42)} archetype cluster. Both compounds crystallize in the triclinic space group P1 with a = 14.3438(4), b = 16.6471(6), c = 18.9186(6) Å, α = 87.291(3)°, β = 83.340(3)°, γ = 78.890(3)°, and V = 4401.4(2) Å(3) (1) and a = 14.5697(13), b = 15.8523(16), c = 20.2411(18) Å, α = 86.702(11)°, β = 84.957(11)°, γ = 76.941(11)°, and V = 4533.0(7) Å(3) (2). In the structure of 1 the [V(15)Sb(6)O(42)(H(2)O)](6-) cluster anion is bound to a [Co(N(3)C(5)H(15))(2)](2+) complex via a terminal oxygen atom. In the Co(2+)-centered complex, one of the amine ligands coordinates in tridentate mode and the second one in bidentate mode to form a strongly distorted CoN(5)O octahedron. Similarly, in compound 2 an analogous NiN(5)O complex is joined to the [V(15)Sb(6)O(42)(H(2)O)](6-) anion via the same attachment mode. A remarkable difference between the two compounds is the orientation of the noncoordinated propylamine group leading to intermolecular Sb···O contacts in 1 and to Sb···N interactions in 2. In the solid-state lattices of 1 and 2, two additional [M(N(3)C(5)H(15))(2)](2+) complexes act as countercations and are located between the [{M(N(3)C(5)H(15))(2)}V(15)Sb(6)O(42)(H(2)O)](4-) anions. Between the anions and cations strong N-H···O hydrogen bonds are observed. In both compounds the clusters are stacked along the b axis in an ABAB fashion with cations and water molecules occupying the space between the clusters. Magnetic characterization demonstrates that the Ni(2+) and Co(2+) cations do not

  9. Input of 129I into the western Pacific Ocean resulting from the Fukushima nuclear event

    DOE PAGES

    Tumey, S. J.; Guilderson, T. P.; Brown, T. A.; ...

    2013-04-02

    We present an initial characterization of the input of 129I into the Pacific Ocean resulting from the 2011 Fukushima nuclear accident. This characterization is based primarily on 129I measurements on samples collected from a research cruise conducted in waters off the eastern coast of Japan in June 2011. The resulting measurements were compared with samples intended to reflect pre-Fukushima background that were collected during a May 2011 transect of the Pacific by a commercial container vessel. In surface waters, we observed peak 129I concentrations of ~300 μBq/m 3 which represents an elevation of nearly three orders of magnitude compared tomore » pre-Fukushima backgrounds. The 129I results were coupled with 137Cs measurements from the same cruise and derived an average 129I/137Cs activity ratio of 0.442 × 10 -6 for the effluent from Fukushima. Finally, we present 129I depth profiles from five stations from this cruise which form the basis for future studies of ocean transport and mixing process as well as estimations of the total budget of 129I released into the Pacific.« less

  10. Input of 129I into the western Pacific Ocean resulting from the Fukushima nuclear event

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

    Tumey, S. J.; Guilderson, T. P.; Brown, T. A.

    We present an initial characterization of the input of 129I into the Pacific Ocean resulting from the 2011 Fukushima nuclear accident. This characterization is based primarily on 129I measurements on samples collected from a research cruise conducted in waters off the eastern coast of Japan in June 2011. The resulting measurements were compared with samples intended to reflect pre-Fukushima background that were collected during a May 2011 transect of the Pacific by a commercial container vessel. In surface waters, we observed peak 129I concentrations of ~300 μBq/m 3 which represents an elevation of nearly three orders of magnitude compared tomore » pre-Fukushima backgrounds. The 129I results were coupled with 137Cs measurements from the same cruise and derived an average 129I/137Cs activity ratio of 0.442 × 10 -6 for the effluent from Fukushima. Finally, we present 129I depth profiles from five stations from this cruise which form the basis for future studies of ocean transport and mixing process as well as estimations of the total budget of 129I released into the Pacific.« less

  11. Determination of 129I in heavy residues of two crude oils

    NASA Astrophysics Data System (ADS)

    Fehn, Udo; Tullai, Sharon; Teng, Ray T. D.; Elmore, David; Kubik, Peter W.

    1987-11-01

    129I/ 127I ratios were determined in heavy residues of two crude oils which were produced from 10 Ma and 300 Ma old formations. The measured 129I/ 127I ratios were between 5 and 10 × 10 -12. These values are significantly above the ratios determined for marine sediments and, for the older oil, also above those supported by in situ production of 129I from uranium. We attribute the high level of 129I in the residues to addition of anthropogenic iodine during the production of the oils. The ratios indicate also that more than 90% of the iodine measured came originally from the oils.

  12. Potential antimicrobial agents from triazole-functionalized 2H-benzo[b][1,4]oxazin-3(4H)-ones.

    PubMed

    Bollu, Rajitha; Banu, Saleha; Bantu, Rajashaker; Reddy, A Gopi; Nagarapu, Lingaiah; Sirisha, K; Kumar, C Ganesh; Gunda, Shravan Kumar; Shaik, Kamal

    2017-12-01

    A series of substituted triazole functionalized 2H-benzo[b][1,4]oxazin-3(4H)-ones were synthesized by employing click chemistry and further characterized based on 1 H NMR, 13 C NMR, IR and mass spectral studies. All the synthesized derivatives were screened for their in vitro antimicrobial activities. Further, molecular docking studies were accomplished to explore the binding interactions between 1,2,3-triazol-4-yl-2H-benzo[b][1,4]oxazin-3(4H)-one and the active site of Staphylococcus aureus (CrtM) dehydrosqualene synthase (PDB ID: 2ZCS). These docking studies revealed that the synthesized derivatives showed high binding energies and strong H-bond interactions with the dehydrosqualene synthase validating the observed antimicrobial activity data. Based on antimicrobial activity and docking studies, the compounds 9c, 9d and 9e were identified as promising antimicrobial leads. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Three closely related 4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridines: synthesis, molecular conformations and hydrogen bonding in zero, one and two dimensions.

    PubMed

    Sagar, Belakavadi K; Harsha, Kachigere B; Yathirajan, Hemmige S; Rangappa, Kanchugarakoppal S; Rathore, Ravindranath S; Glidewell, Christopher

    2017-03-01

    In each of 1-(4-fluorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C 21 H 19 F 4 N 3 O 2 S, (I), 1-(4-chlorophenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C 21 H 19 ClF 3 N 3 O 2 S, (II), and 1-(3-methylphenyl)-5-methylsulfonyl-3-[4-(trifluoromethyl)phenyl]-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c]pyridine, C 22 H 22 F 3 N 3 O 2 S, (III), the reduced pyridine ring adopts a half-chair conformation with the methylsulfonyl substituent occupying an equatorial site. Although compounds (I) and (II) are not isostructural, having the space groups Pbca and P2 1 2 1 2 1 , respectively, their molecular conformations are very similar, but the conformation of compound (III) differs from those of (I) and (II) in the relative orientation of the N-benzyl and methylsulfonyl substituents. In compounds (II) and (III), but not in (I), the trifluoromethyl groups are disordered over two sets of atomic sites. Molecules of (I) are linked into centrosymmetric dimers by C-H...π(arene) hydrogen bonds, molecules of (II) are linked by two C-H...O hydrogen bonds to form ribbons of R 3 3 (18) rings, which are themselves further linked by a C-Cl...π(arene) interaction, and a combination of C-H...O and C-H...π(arene) hydrogen bonds links the molecules of (III) into sheets. Comparisons are made with the structures of some related compounds.

  14. Measles-virus-persistent infection in BGM cells. Modification of the incorporation of [3H]arachidonic acid and [14C]stearic acid into lipids.

    PubMed Central

    Anderton, P; Wild, T F; Zwingelstein, G

    1983-01-01

    In BGM cells chronically infected with measles virus, although the composition of the phospholipids is unaltered, the fatty acid composition is modified. Uninfected, lytic and persistently infected cells were labelled with [3H]arachidonic acid and [14C]stearic acid and their metabolic fate analysed. No difference in the total incorporation was observed in the different systems. However, the [14C]stearic acid and [3H]arachidonic acid were incorporated up to 2-fold and 13-fold respectively greater into the neutral lipid of persistently infected compared with that of uninfected cells. Both radioactive fatty acids were specifically accumulated in the triacylglycerol and non-esterified fatty acids fractions. Lytically infected cells were similar to uninfected cells. Although there was no significant difference in the incorporation of radioactivity into the total phospholipid in either system, there was a large decrease in [3H]arachidonic acid incorporated into phosphatidylethanolamine and to a lesser extent phosphatidylcholine and phosphatidylinositol in persistently infected cells. [14C]Stearic acid incorporation was also reduced in phosphatidylcholine and phosphatidylethanolamine fractions of persistently infected cells. PMID:6414459

  15. Phase Equilibria and Transport Properties in the Systems AgNO3/RCN/H2O. R = CH3, C2H5, C3H7, C4H,, C6H5, and C6H5CH2

    NASA Astrophysics Data System (ADS)

    Das, Surjya P.; Wittekopf, Burghard; Weil, Konrad G.

    1988-11-01

    Silver nitrate can form homogeneous liquid phases with some organic nitriles and water, even when there is no miscibility between the pure liquid components. We determined the shapes of the single phase regions in the ternary phase diagram for the following systems: silver nitrate /RCN /H2O with R =CH3, C3H7, C6H5, and C6H5CH2 at room temperature and for R =C6H5 also at 60 °C and O °C. Furthermore we studied kinematic viscosities, electrical conductivities, and densities of mixtures containing silver nitrate, RCN, and water with the mole ratios X /4 /1 (0.2≦ X ≦S 3.4). In these cases also R = C2H5 and C4H9 were studied. The organic nitriles show different dependences of viscosity and conductivity on the silver nitrate content from the aliphatic ones.

  16. Observation of radioactive iodine ((131)I, (129)I) in cropland soil after the Fukushima nuclear accident.

    PubMed

    Fujiwara, Hideshi

    2016-10-01

    During the early stages of the Fukushima nuclear accident, the temporal variations of (131)I deposited on the ground and of (131)I accumulated in cropland soil were monitored at a fixed location in Japan. Moreover, concentrations of long-lived radioactive iodine ((129)I) in atmospheric deposits and soil were measured to examine the feasibility of retrospectively reconstructing (131)I levels from the levels of accident-derived (129)I. The exceptionally high levels of (131)I in deposits and soil were attributed to rainfall-related deposition of radionuclides. In the crop field studied, the losses of deposited (131)I and (129)I due to volatilization were small. The atomic ratio (129)I/(131)I in the topsoil corresponded to the same ratio in deposits. The (131)I concentrations measured in the topsoil were very consistent with the (131)I concentrations reconstructed from the (129)I concentrations in the soil. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Level and source of 129I of environmental samples in Xi'an region, China.

    PubMed

    Zhang, Luyuan; Zhou, Weijian; Hou, Xiaolin; Chen, Ning; Liu, Qi; He, Chaohui; Fan, Yukun; Luo, Maoyi; Wang, Zhiwen; Fu, Yunchong

    2011-09-01

    Iodine-129 is widely used as a tracer in various environmental practices such as monitoring of nuclear environmental safety, seawater exchange and transport, geochemical cycle of stable iodine and dating of geological events. The spatial distribution of (129)I concentration varies significantly on global scale because of anthropogenic input from nuclear activities coupled with scarcity of data on environmental (129)I variability in many parts of the world including Asia. Here we report new data on (129)I and (127)I concentrations in soil, vegetation, river water and precipitation collected from Xi'an area, China. The results indicate values for environmental (129)I/(127)I ratios in the investigated area range from 1.1×10(-10) to 43.5×10(-10) with a mean of 20.6×10(-10), which is 1-3 orders of magnitude lower than the ratios observed in Europe, but comparable with those observed in the locations far from direct effect of point release sources and at similar latitude. The main source of (129)I in the investigated area is attributed to the global fallout of both atmospheric nuclear weapons testing and long distance dispersion of fuel reprocessing releases. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. High-resolution 129I bomb peak profile in an ice core from SE-Dome site, Greenland.

    PubMed

    Bautista, Angel T; Miyake, Yasuto; Matsuzaki, Hiroyuki; Iizuka, Yoshinori; Horiuchi, Kazuho

    2018-04-01

    129 I in natural archives, such as ice cores, can be used as a proxy for human nuclear activities, age marker, and environmental tracer. Currently, there is only one published record of 129 I in ice core (i.e., from Fiescherhorn Glacier, Swiss Alps) and its limited time resolution (1-2 years) prevents the full use of 129 I for the mentioned applications. Here we show 129 I concentrations in an ice core from SE-Dome, Greenland, covering years 1956-1976 at a time resolution of ∼6 months, the most detailed record to date. Results revealed 129 I bomb peaks in years 1959, 1962, and 1963, associated to tests performed by the former Soviet Union, one year prior, in its Novaya Zemlya test site. All 129 I bomb peaks were observed in winter (1958.9, 1962.1, and 1963.0), while tritium bomb peaks, another prominent radionuclide associated with nuclear bomb testing, were observed in spring or summer (1959.3, and 1963.6; Iizuka et al., 2017). These results indicate that 129 I bomb peaks can be used as annual and seasonal age markers for these years. Furthermore, we found that 129 I recorded nuclear fuel reprocessing signals and that these can be potentially used to correct timing of estimated 129 I releases during years 1964-1976. Comparisons with other published records of 129 I in natural archives showed that 129 I can be used as common age marker and tracer for different types of records. Most notably, the 1963 129 I bomb peak can be used as common age marker for ice and coral cores, providing the means to reconcile age models and associated trends from the polar and tropical regions, respectively. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. 31 CFR 129.3 - Reporting requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 31 Money and Finance: Treasury 1 2013-07-01 2013-07-01 false Reporting requirements. 129.3 Section 129.3 Money and Finance: Treasury Regulations Relating to Money and Finance MONETARY OFFICES, DEPARTMENT OF THE TREASURY PORTFOLIO INVESTMENT SURVEY REPORTING § 129.3 Reporting requirements. (a) Notice...

  20. 31 CFR 129.3 - Reporting requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 31 Money and Finance: Treasury 1 2014-07-01 2014-07-01 false Reporting requirements. 129.3 Section 129.3 Money and Finance: Treasury Regulations Relating to Money and Finance MONETARY OFFICES, DEPARTMENT OF THE TREASURY PORTFOLIO INVESTMENT SURVEY REPORTING § 129.3 Reporting requirements. (a) Notice...

  1. 31 CFR 129.3 - Reporting requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 31 Money and Finance: Treasury 1 2010-07-01 2010-07-01 false Reporting requirements. 129.3 Section 129.3 Money and Finance: Treasury Regulations Relating to Money and Finance PORTFOLIO INVESTMENT SURVEY REPORTING § 129.3 Reporting requirements. (a) Notice of specific reporting requirements, including...

  2. Semiconducting perovskites (2-XC6H4C2H4NH3)2SnI4 (X = F, Cl, Br): steric interaction between the organic and inorganic layers.

    PubMed

    Xu, Zhengtao; Mitzi, David B; Dimitrakopoulos, Christos D; Maxcy, Karen R

    2003-03-24

    Two new semiconducting hybrid perovskites based on 2-substituted phenethylammonium cations, (2-XC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) (X = Br, Cl), are characterized and compared with the previously reported X = F compound, with a focus on the steric interaction between the organic and inorganic components. The crystal structure of (2-ClC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) is solved in a disordered subcell [C2/m, a = 33.781(7) A, b = 6.178(1) A, c = 6.190(1) A, beta = 90.42(3)(o), and Z = 2]. The structure is similar to the known (2-FC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) structure with regard to both the conformation of the organic cations and the bonding features of the inorganic sheet. The (2-BrC(6)H(4)C(2)H(4)NH(3))(2)SnI(4) system adopts a fully ordered monoclinic cell [P2(1)/c, a = 18.540(2) A, b = 8.3443(7) A, c = 8.7795(7) A, beta = 93.039(1)(o), and Z = 2]. The organic cation adopts the anti conformation, instead of the gauche conformation observed in the X = F and Cl compounds, apparently because of the need to accommodate the additional volume of the bromo group. The steric effect of the bromo group also impacts the perovskite sheet, causing notable distortions, such as a compressed Sn-I-Sn bond angle (148.7(o), as compared with the average values of 153.3 and 154.8(o) for the fluoro and chloro compounds, respectively). The optical absorption features a substantial blue shift (lowest exciton peak: 557 nm, 2.23 eV) relative to the spectra of the fluoro and chloro compounds (588 and 586 nm, respectively). Also presented are transport properties for thin-film field-effect transistors (TFTs) based on spin-coated films of the two hybrid semiconductors.

  3. C-H activations at iridium(I) square-planar complexes promoted by a fifth ligand.

    PubMed

    Martín, Marta; Torres, Olga; Oñate, Enrique; Sola, Eduardo; Oro, Luis A

    2005-12-28

    In the presence of ligands such as acetonitrile, ethylene, or propylene, the Ir(I) complex [Ir(1,2,5,6-eta-C8H12)(NCMe)(PMe3)]BF4 (1) transforms into the Ir(III) derivatives [Ir(1-kappa-4,5,6-eta-C8H12)(NCMe)(L)(PMe3)]BF4 (L = NCMe, 2; eta2-C2H4, 3; eta2-C3H6, 4), respectively, through a sequence of C-H oxidative addition and insertion elementary steps. The rate of this transformation depends on the nature of L and, in the case of NCMe, the pseudo-first-order rate constants display a dependence upon ligand concentration suggesting the formation of five-coordinate reaction intermediates. A similar reaction between 1 and vinyl acetate affords the Ir(III) complex [Ir(1-kappa-4,5,6-eta-C8H12){kappa-O-eta2-OC(Me)OC2H3}(PMe3)]BF4 (7) via the isolable five-coordinate Ir(I) compound [Ir(1,2,5,6-eta-C8H12){kappa-O-eta2-OC(Me)OC2H3}(PMe3)]BF4 (6). DFT (B3LYP) calculations in model complexes show that reactions initiated by acetonitrile or ethylene five-coordinate adducts involve C-H oxidative addition transition states of lower energy than that found in the absence of these ligands. Key species in these ligand-assisted transformations are the distorted (nonsquare-planar) intermediates preceding the intramolecular C-H oxidative addition step, which are generated after release of one cyclooctadiene double bond from the five-coordinate species. The feasibility of this mechanism is also investigated for complexes [IrCl(L)(PiPr3)2] (L = eta2-C2H4, 27; eta2-C3H6, 28). In the presence of NCMe, these complexes afford the C-H activation products [IrClH(CH=CHR)(NCMe)(PiPr3)2] (R = H, 29; Me, 30) via the common cyclometalated intermediate [IrClH{kappa-P,C-P(iPr)2CH(CH3)CH2}(NCMe)(PiPr3)] (31). The most effective C-H oxidative addition mechanism seems to involve three-coordinate intermediates generated by photochemical release of the alkene ligand. However, in the absence of light, the reaction rates display dependences upon NCMe concentration again indicating the intermediacy of five

  4. Proton relays in anomalous carbocations dictate spectroscopy, stability, and mechanisms: case studies on C2H5+ and C3H3.

    PubMed

    Sager, LeeAnn M; Iyengar, Srinivasan S

    2017-10-18

    We present a detailed analysis of the anomalous carbocations: C 2 H 5 + and C 3 H 3 + . This work involves (a) probing electronic structural properties, (b) ab initio dynamics simulations over a range of internal energies, (c) analysis of reduced dimensional potential surfaces directed along selected conformational transition pathways, (d) dynamically averaged vibrational spectra computed from ab initio dynamics trajectories, and (e) two-dimensional time-frequency analysis to probe conformational dynamics. Key findings are as follows: (i) as noted in our previous study on C 2 H 3 + , it appears that these non-classical carbocations are stabilized by delocalized nuclear frameworks and "proton shuttles". We analyze this nuclear delocalization and find critical parallels between conformational changes in C 2 H 3 + , C 2 H 5 + , and C 3 H 3 + . (ii) The vibrational signatures of C 2 H 5 + are dominated by the "bridge-proton" conformation, but also show critical contributions from the "classical" configuration, which is a transition state at almost all levels of theory. This result is further substantiated through two-dimensional time-frequency analysis and is at odds with earlier explanations of the experimental spectra, where frequencies close to the classical region were thought to arise from an impurity. While this is still possible, our results here indicate an additional (perhaps more likely) explanation that involves the "classical" isomer. (iii) Finally, in the case of C 3 H 3 + our explanation of the experimental result includes the presence of multiple, namely, "cyclic", "straight", and propargyl, configurations. Proton shuttles and nuclear delocalization, reminiscent of those seen in the case of C 2 H 3 + , were seen all through and have a critical role in all our observations.

  5. Iodine isotopes (129I and 127I) in the hydrosphere of Qinghai-Tibet region and South China Sea.

    PubMed

    Yi, Peng; Chen, Xuegao; Wang, Zixia; Aldahan, Ala; Hou, Xiaolin; Yu, Zhongbo

    2018-06-14

    The radioactive isotope 129 I, with a half-life of 1.57 × 10 7 years, is widely used as a tracer to assess nuclear safety, to track environmental and geological events and to figure out the details of the stable iodine geochemical cycle. This work investigated the 129 I and 127 I distribution in water samples collected from the terrestrial (rivers, lakes and springs) and marine water systems (estuary and sea) in China. The measured 129 I concentrations of (1-51) × 10 6 atoms/L and 129 I/ 127 I ratios of (0.03-21) × 10 -10 shows the variability of 129 I level in the water systems. The local permafrost and seasonal frozen environment play a key role in groundwater recharge in the Qinghai-Tibet region, which is reflected in the 129 I distribution in surface water. The depth distribution of 129 I in the water column of the South China Sea reflects the effluence of different currents. The results also indicate that the hydrosphere of China contains one to three orders of magnitude less 129 I compared to those reported in Europe. Despite the large distance, the European nuclear fuel reprocessing facilities represent the major source of 129 I in the hydrosphere of China through atmospheric transport. The contribution of the Fukushima nuclear accident to 129 I levels in the hydrosphere of China was negligible. Copyright © 2018 Elsevier Ltd. All rights reserved.

  6. The effect of the hydrogen fluoride chain on the aromaticity of C6H6 in the C6H6...(HF)1-4 complexes

    NASA Astrophysics Data System (ADS)

    Jouypazadeh, Hamidreza; Farrokhpour, Hossein; Solimannejad, Mohammad

    2018-02-01

    The effect of the hydrogen fluoride chain ((HF)n) on the aromaticity and π character of C-C bonds of C6H6 in the C6H6...(HF)n (n = 1-4) complexes were investigated using density functional theory employing RM05 functional. It was found that the binding energy between C6H6 and different (HF)n chains showed a maximum at n = 3 (C6H6...(HF)3). Also, the π-hydrogen interaction (πHI) and the bifurcated fluorine interaction (BFI) increased and decreased the π character of the C-C bond of C6H6, respectively. In addition, the change of aromaticity of the C6H6 due to the interaction with the HF chains was also studied using three different aspects such as aromatic fluctuation index (FLU), average two centre index (ATI) and proton nuclear magnetic resonance (HNMR) spectrum. The most change in the aromaticity happens when the C6H6 interacts with (HF)3 chain. The variation of aromaticity with the binding energy and the summation of two-body terms were investigated and very good linear correlations were observed.

  7. The Tick-Over Theory Revisited: Formation and Regulation of the Soluble Alternative Complement C3 Convertase (C3(H2O)Bb)

    PubMed Central

    Bexborn, Fredrik; Andersson, Per Ola; Chen, Hui; Nilsson, Bo; Ekdahl, Kristina N.

    2009-01-01

    The molecular interactions between the components of the C3 convertase of the alternative pathway (AP) of complement and its regulators, in both surface-bound and fluid-phase form, are still incompletely understood. The fact that the AP convertase is labile makes studies difficult to perform. According to the so called tick-over theory, hydrolyzed C3, called C3(H2O), forms the initial convertase in fluid phase together with factor B. In the present study, we have applied western blot analysis and ELISA together with fluorescence resonance energy transfer (FRET) to study the formation of the fluid-phase AP convertases C3(H2O)Bb and C3bBb and their regulation by factor H and factor I at specific time points and, with FRET, in real time. In our hands, factor B showed a higher affinity for C3(H2O) than for C3b, although in both cases it was readily activated to Bb. However, the convertase activity of C3bBb was approximately twice that of C3(H2O)Bb, as monitored by the generation of C3a. But in contrast, the C3(H2O)Bb convertase was more resistant to inactivation by factor H and factor I than was the C3bBb convertase. Under conditions that totally inactivated C3bBb, C3(H2O)Bb still retained approximately 25% of its initial activity. PMID:18096230

  8. The tick-over theory revisited: formation and regulation of the soluble alternative complement C3 convertase (C3(H2O)Bb).

    PubMed

    Bexborn, Fredrik; Andersson, Per Ola; Chen, Hui; Nilsson, Bo; Ekdahl, Kristina N

    2008-04-01

    The molecular interactions between the components of the C3 convertase of the alternative pathway (AP) of complement and its regulators, in both surface-bound and fluid-phase form, are still incompletely understood. The fact that the AP convertase is labile makes studies difficult to perform. According to the so called tick-over theory, hydrolyzed C3, called C3(H(2)O), forms the initial convertase in fluid phase together with factor B. In the present study, we have applied western blot analysis and ELISA together with fluorescence resonance energy transfer (FRET) to study the formation of the fluid-phase AP convertases C3(H(2)O)Bb and C3bBb and their regulation by factor H and factor I at specific time points and, with FRET, in real time. In our hands, factor B showed a higher affinity for C3(H(2)O) than for C3b, although in both cases it was readily activated to Bb. However, the convertase activity of C3bBb was approximately twice that of C3(H(2)O)Bb, as monitored by the generation of C3a. But in contrast, the C3(H(2)O)Bb convertase was more resistant to inactivation by factor H and factor I than was the C3bBb convertase. Under conditions that totally inactivated C3bBb, C3(H(2)O)Bb still retained approximately 25% of its initial activity.

  9. Full exploration of the Diels-Alder cycloaddition on metallofullerenes M3N@C80 (M = Sc, Lu, Gd): the D(5h) versus I(h) isomer and the influence of the metal cluster.

    PubMed

    Osuna, Sílvia; Valencia, Ramón; Rodríguez-Fortea, Antonio; Swart, Marcel; Solà, Miquel; Poblet, Josep M

    2012-07-16

    In this work a detailed investigation of the exohedral reactivity of the most important and abundant endohedral metallofullerene (EMF) is provided, that is, Sc(3)N@I(h)-C(80) and its D(5h) counterpart Sc(3)N@D(5h)-C(80) , and the (bio)chemically relevant lutetium- and gadolinium-based M(3)N@I(h)/D(5h)-C(80) EMFs (M = Sc, Lu, Gd). In particular, we analyze the thermodynamics and kinetics of the Diels-Alder cycloaddition of s-cis-1,3-butadiene on all the different bonds of the I(h)-C(80) and D(5h)-C(80) cages and their endohedral derivatives. First, we discuss the thermodynamic and kinetic aspects of the cycloaddition reaction on the hollow fullerenes and the two isomers of Sc(3)N@C(80). Afterwards, the effect of the nature of the metal nitride is analyzed in detail. In general, our BP86/TZP//BP86/DZP calculations indicate that [5,6] bonds are more reactive than [6,6] bonds for the two isomers. The [5,6] bond D(5h)-b, which is the most similar to the unique [5,6] bond type in the icosahedral cage, I(h)-a, is the most reactive bond in M(3)N@D(5h)-C(80) regardless of M. Sc(3)N@C(80) and Lu(3)N@C(80) give similar results; the regioselectivity is, however, significantly reduced for the larger and more electropositive M = Gd, as previously found in similar metallofullerenes. Calculations also show that the D(5h) isomer is more reactive from the kinetic point of view than the I(h) one in all cases which is in good agreement with experiments. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. CFD Growth of 3C-SiC on 4H/6H Mesas

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Trunek, Andrew J.; Spry, David J.; Powell, J. Anthony; Du, Hui; Skowronski, Marek; Huang, XianRong; Dudley, Michael

    2006-01-01

    This article describes growth and characterization of the highest quality reproducible 3C-SiC heteroepitaxial films ever reported. By properly nucleating 3C-SiC growth on top of perfectly on-axis (0001) 4H-SiC mesa surfaces completely free of atomic scale steps and extended defects, growth of 3C-SiC mesa heterofilms completely free of extended crystal defects can be achieved. In contrast, nucleation and growth of 3C-SiC mesa heterofilms on top of 4H-SiC mesas with atomic-scale steps always results in numerous observable dislocations threading through the 3C-SiC epilayer. High-resolution X-ray diffraction and transmission electron microscopy measurements indicate non-trivial in-plane lattice mismatch between the 3C and 4H layers. This mismatch is somewhat relieved in the step-free mesa case via misfit dislocations confined to the 3C/4H interfacial region without dislocations threading into the overlying 3C-SiC layer. These results indicate that the presence or absence of steps at the 3C/4H heteroepitaxial interface critically impacts the quality, defect structure, and relaxation mechanisms of single-crystal heteroepitaxial 3C-SiC films.

  11. 129I in the oceans: origins and applications.

    PubMed

    Raisbeck, G M; Yiou, F

    1999-09-30

    The quantity of the long lived (half-life 15.7 million years) radioactive isotope 129I in the pre-nuclear age ocean was approximately 100 kg. Various nuclear related activities, including weapons testing, nuclear fuel reprocessing, Chernobyl and other authorized or non-authorized dumping of radioactive waste have increased the ocean inventory of 129I by more than one order of magnitude. The most important of these sources are the direct marine discharges from the commercial reprocessing facilities at La Hague (France) and Sellafield (UK) which have discharged approximately 1640 kg in the English Channel, and approximately 720 kg in the Irish Sea, respectively. We discuss how this 129I can be used as both a 'pathway' and 'transit time' tracer in the North Atlantic and Arctic oceans, as well as a parameter for distinguishing between reprocessed and non-reprocessed nuclear waste in the ocean, and as a proxy for the transport and dilution of other soluble pollutants input to the North Sea.

  12. 14-3-3 proteins mediate inhibitory effects of cAMP on salt-inducible kinases (SIKs).

    PubMed

    Sonntag, Tim; Vaughan, Joan M; Montminy, Marc

    2018-02-01

    The salt-inducible kinase (SIK) family regulates cellular gene expression via the phosphorylation of cAMP-regulated transcriptional coactivators (CRTCs) and class IIA histone deacetylases, which are sequestered in the cytoplasm by phosphorylation-dependent 14-3-3 interactions. SIK activity toward these substrates is inhibited by increases in cAMP signaling, although the underlying mechanism is unclear. Here, we show that the protein kinase A (PKA)-dependent phosphorylation of SIKs inhibits their catalytic activity by inducing 14-3-3 protein binding. SIK1 and SIK3 contain two functional PKA/14-3-3 sites, while SIK2 has four. In keeping with the dimeric nature of 14-3-3s, the presence of multiple binding sites within target proteins dramatically increases binding affinity. As a result, loss of a single 14-3-3-binding site in SIK1 and SIK3 abolished 14-3-3 association and rendered them insensitive to cAMP. In contrast, mutation of three sites in SIK2 was necessary to fully block cAMP regulation. Superimposed on the effects of PKA phosphorylation and 14-3-3 association, an evolutionary conserved domain in SIK1 and SIK2 (the so called RK-rich region; 595-624 in hSIK2) is also required for the inhibition of SIK2 activity. Collectively, these results point to a dual role for 14-3-3 proteins in repressing a family of Ser/Thr kinases as well as their substrates. © 2017 Federation of European Biochemical Societies.

  13. 9 CFR 3.129 - Feeding.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Warmblooded Animals Other Than Dogs, Cats, Rabbits, Hamsters, Guinea Pigs, Nonhuman Primates, and Marine... 9 Animals and Animal Products 1 2013-01-01 2013-01-01 false Feeding. 3.129 Section 3.129 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL...

  14. 9 CFR 3.129 - Feeding.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Warmblooded Animals Other Than Dogs, Cats, Rabbits, Hamsters, Guinea Pigs, Nonhuman Primates, and Marine... 9 Animals and Animal Products 1 2014-01-01 2014-01-01 false Feeding. 3.129 Section 3.129 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL...

  15. 9 CFR 3.129 - Feeding.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Warmblooded Animals Other Than Dogs, Cats, Rabbits, Hamsters, Guinea Pigs, Nonhuman Primates, and Marine... 9 Animals and Animal Products 1 2011-01-01 2011-01-01 false Feeding. 3.129 Section 3.129 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL...

  16. 9 CFR 3.129 - Feeding.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Warmblooded Animals Other Than Dogs, Cats, Rabbits, Hamsters, Guinea Pigs, Nonhuman Primates, and Marine... 9 Animals and Animal Products 1 2012-01-01 2012-01-01 false Feeding. 3.129 Section 3.129 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE, DEPARTMENT OF AGRICULTURE ANIMAL...

  17. Rh(I) -Catalyzed Intramolecular Carbonylative C-H/C-I Coupling of 2-Iodobiphenyls Using Furfural as a Carbonyl Source.

    PubMed

    Furusawa, Takuma; Morimoto, Tsumoru; Nishiyama, Yasuhiro; Tanimoto, Hiroki; Kakiuchi, Kiyomi

    2016-08-19

    Synthesis of fluoren-9-ones by a Rh-catalyzed intramolecular C-H/C-I carbonylative coupling of 2-iodobiphenyls using furfural as a carbonyl source is presented. The findings indicate that the rate-determining step is not a C-H bond cleavage but, rather, the oxidative addition of the C-I bond to a Rh(I) center. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Europium-Labeled Synthetic C3a Protein as a Novel Fluorescent Probe for Human Complement C3a Receptor.

    PubMed

    Dantas de Araujo, Aline; Wu, Chongyang; Wu, Kai-Chen; Reid, Robert C; Durek, Thomas; Lim, Junxian; Fairlie, David P

    2017-06-21

    Measuring ligand affinity for a G protein-coupled receptor is often a crucial step in drug discovery. It has been traditionally determined by binding putative new ligands in competition with native ligand labeled with a radioisotope of finite lifetime. Competing instead with a lanthanide-based fluorescent ligand is more attractive due to greater longevity, stability, and safety. Here, we have chemically synthesized the 77 residue human C3a protein and conjugated its N-terminus to europium diethylenetriaminepentaacetate to produce a novel fluorescent protein (Eu-DTPA-hC3a). Time-resolved fluorescence analysis has demonstrated that Eu-DTPA-hC3a binds selectively to its cognate G protein-coupled receptor C3aR with full agonist activity and similar potency and selectivity as native C3a in inducing calcium mobilization and phosphorylation of extracellular signal-regulated kinases in HEK293 cells that stably expressed C3aR. Time-resolved fluorescence analysis for saturation and competitive binding gave a dissociation constant (K d ) of 8.7 ± 1.4 nM for Eu-DTPA-hC3a and binding affinities for hC3a (pK i of 8.6 ± 0.2 and K i of 2.5 nM) and C3aR ligands TR16 (pK i of 6.8 ± 0.1 and K i of 138 nM), BR103 (pK i of 6.7 ± 0.1 and K i of 185 nM), BR111 (pK i of 6.3 ± 0.2 and K i of 544 nM) and SB290157 (pK i of 6.3 ± 0.1 and K i of 517 nM) via displacement of Eu-DTPA-hC3a from hC3aR. The macromolecular conjugate Eu-DTPA-hC3a is a novel nonradioactive probe suitable for studying ligand-C3aR interactions with potential value in accelerating drug development for human C3aR in physiology and disease.

  19. The phosphatidylinositol transfer protein RdgBβ binds 14-3-3 via its unstructured C-terminus, whereas its lipid-binding domain interacts with the integral membrane protein ATRAP (angiotensin II type I receptor-associated protein).

    PubMed

    Garner, Kathryn; Li, Michelle; Ugwuanya, Natalie; Cockcroft, Shamshad

    2011-10-01

    PITPs [PI (phosphatidylinositol) transfer proteins] bind and transfer PI between intracellular membranes and participate in many cellular processes including signalling, lipid metabolism and membrane traffic. The largely uncharacterized PITP RdgBβ (PITPNC1; retinal degeneration type B β), contains a long C-terminal disordered region following its defining N-terminal PITP domain. In the present study we report that the C-terminus contains two tandem phosphorylated binding sites (Ser(274) and Ser(299)) for 14-3-3. The C-terminus also contains PEST sequences which are shielded by 14-3-3 binding. Like many proteins containing PEST sequences, the levels of RdgBβ are regulated by proteolysis. RdgBβ is degraded with a half-life of 4 h following ubiquitination via the proteasome. A mutant RdgBβ which is unable to bind 14-3-3 is degraded even faster with a half-life of 2 h. In vitro, RdgBβ is 100-fold less active than PITPα for PI transfer, and RdgBβ proteins (wild-type and a mutant that cannot bind 14-3-3) expressed in COS-7 cells or endogenous proteins from heart cytosol do not exhibit transfer activity. When cells are treated with PMA, the PITP domain of RdgBβ interacts with the integral membrane protein ATRAP (angiotensin II type I receptor-associated protein; also known as AGTRAP) causing membrane recruitment. We suggest that RdgBβ executes its function following recruitment to membranes via its PITP domain and the C-terminal end of the protein could regulate entry to the hydrophobic cavity.

  20. 14. Photocopy of photograph (from William H. Knowles Collection, c. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Photocopy of photograph (from William H. Knowles Collection, c. 1880) EXTERIOR, SOUTH FRONT AND WEST SIDE OF MISSION, C. 1880 - Mission San Francisco Solano de Sonoma, First & Spain Streets, Sonoma, Sonoma County, CA

  1. Is soil natural organic matter a sink or source for mobile radioiodine ( 129 I) at the Savannah River Site?

    NASA Astrophysics Data System (ADS)

    Xu, Chen; Zhang, Saijin; Ho, Yi-Fang; Miller, Eric J.; Roberts, Kimberly A.; Li, Hsiu-Ping; Schwehr, Kathleen A.; Otosaka, Shigeyoshi; Kaplan, Daniel I.; Brinkmeyer, Robin; Yeager, Chris M.; Santschi, Peter H.

    2011-10-01

    129I is one of the three major radiation risk contributors to the public as a consequence of past nuclear processing activities at Department of Energy (DOE) facilities. Elevated levels of 129I are present in the surface soils of F-Area of Savannah River Site, which used to be an isotope separation facility for the production of nuclear weapons components. The 129I in soils is thought to be bound predominantly to soil organic matter (SOM). Measurements of stable 127I and radioactive 129I in humic acids (HAs) and fulvic acids (FAs) obtained by five successive alkaline, two glycerol and one citric acid-alkaline extraction, demonstrated that these extractable humic substances (HS) together account for 54-56% and 46% of the total 127I and 129I in the soil, respectively. The remainder was likely bound to residual SOM. The iodine content (μg-I/g-C) generally decreased with each subsequent extract, while 129I/ 127I increased concurrently. The coincident variations in chemical compositions, aromaticity (estimated by UV spectroscopy), functional groups (e.g., aliphatic), degree of humification, relative migration in the hydrophobic interaction column, and molecular weight indicated that: (1) iodine in different HAs was bound to a small-size aromatic subunit (˜10 kDa); (2) the large-size subunit (˜90 kDa), which likely linked the small-size unit through some weak chemical forces (hydrogen bonds, hydrophobic or electrostatic interactions), determined the relative mobility of iodine bound to organic matter; (3) from the strong correlation between iodine content and aromaticity in the HAs, we suggested that iodine incorporation into the SOM via covalent aromatic C-I bond is the key mechanism controlling iodine behavior in this system. However, this relationship is not universal for all fractions of organic matter as evidenced from the different slopes of this relationship at the two sampling sites, as well as from the different relationships for HAs and FAs, respectively

  2. Syntheses, structures, and vibrational spectroscopy of the two-dimensional iodates Ln(IO 3) 3 and Ln(IO 3) 3(H 2O) ( Lndbnd Yb, Lu)

    NASA Astrophysics Data System (ADS)

    Assefa, Zerihun; Ling, Jie; Haire, Richard G.; Albrecht-Schmitt, Thomas E.; Sykora, Richard E.

    2006-12-01

    The reaction of Lu 3+ or Yb 3+ and H 5IO 6 in aqueous media at 180 °C leads to the formation of Yb(IO 3) 3(H 2O) or Lu(IO 3) 3(H 2O), respectively, while the reaction of Yb metal with H 5IO 6 under similar reaction conditions gives rise to the anhydrous iodate, Yb(IO 3) 3. Under supercritical conditions Lu 3+ reacts with HIO 3 and KIO 4 to yield the isostructural Lu(IO 3) 3. The structures have been determined by single-crystal X-ray diffraction. Crystallographic data are (Mo Kα, λ=0.71073 Å): Yb(IO 3) 3, monoclinic, space group P2 1/ n, a=8.6664(9) Å, b=5.9904(6) Å, c=14.8826(15) Å, β=96.931(2)°, V=766.99(13), Z=4, R( F)=4.23% for 114 parameters with 1880 reflections with I>2 σ( I); Lu(IO 3) 3, monoclinic, space group P2 1/ n, a=8.6410(9), b=5.9961(6), c=14.8782(16) Å, β=97.028(2)°, V=765.08(14), Z=4, R( F)=2.65% for 119 parameters with 1756 reflections with I>2 σ( I); Yb(IO 3) 3(H 2O), monoclinic, space group C2/ c, a=27.2476(15), b=5.6296(3), c=12.0157(7) Å, β=98.636(1)°, V=1822.2(2), Z=8, R( F)=1.51% for 128 parameters with 2250 reflections with I>2 σ( I); Lu(IO 3) 3(H 2O), monoclinic, space group C2/ c, a=27.258(4), b=5.6251(7), c=12.0006(16) Å, β=98.704(2)°, V=1818.8(4), Z=8, R( F)=1.98% for 128 parameters with 2242 reflections with I>2 σ( I). The f elements in all of the compounds are found in seven-coordinate environments and bridged with monodentate, bidentate, or tridentate iodate anions. Both Lu(IO 3) 3(H 2O) and Yb(IO 3) 3(H 2O) display distinctively different vibrational profiles from their respective anhydrous analogs. Hence, the Raman profile can be used as a complementary diagnostic tool to discern the different structural motifs of the compounds.

  3. Isotropic C6, C8 and C10 interaction coefficients for CH 4, C 2H 6, C 3H 8, n-C 4H 10 and cyclo- C3H 6

    NASA Astrophysics Data System (ADS)

    Thomas, Gerald F.; Mulder, Fred; Meath, William J.

    1980-12-01

    The non-empirical generalized Kirkwood, Unsöld, and the single-Δ Unsöld methods (with double-zeta quality SCF wave-functions) are used to calculate isotropic dispersion (and induction) energy coefficients C2n, with n ⩽ 5, for interactions involving ground state CH 4, C 2H 6, C 3H 8, n-C 4H 10 and cyclo-C 3H 6. Results are also given for the related multipole polarizabilities α l, multipole sums S1/(0) and S1(-1) which are evaluated using sum rules, and the permanent multipole moments. for l = 1 (dipole) to l = 3 (octupole). Estimates of the reliability of the non-empirical methods, for the type of molecules considered, are obtained by a comparison with accurate literature values of α 1S1(-1) and C6. This, and the asymptotic properties of the multipolar expansion of the dispersion energy, the use to discuss recommended representation for the isotropic long range interaction energies through R-10 where R is the intermolecular separation.

  4. VizieR Online Data Catalog: Gas-phase detection of c-C3H3

    NASA Astrophysics Data System (ADS)

    Zhao, D.; Doney, K. D.; Linnartz, H.

    2017-03-01

    The experimental setup has been described in detail by Zhao et al. (2013CPL...565..132Z, 2014JMoSp.296....1Z). In brief, the c-C3H3+ cations are generated by discharging a propyne (C3H4):He ~ 1:200 gas mixture in a multi-layer slit discharge nozzle (Motylewski & Linnartz 1999RScI...70.1305M) in combination with a pulsed valve (General Valve, Series 9,2 mm orifice). The gas mixture is expanded with a backing pressure of ~7 bar through a 300umx3cm slit into a vacuum chamber. A pulsed negative high voltage (-600 V/300 mA) with a ~600 us duration is found to be optimum for c-C3H3+ production, is applied to the expanding gas mixture, and is set to coincide with the expanding gas pulse (~800 us). Continuous-wave cavity ring-down spectroscopy (cw-CRDS) is used to record spectra in direct absorption. The axis of the optical cavity is aligned parallel to and ~2 mm downstream of the slit nozzle throat. A single-mode cw optical parametric oscillator (Aculight), operating at ~3.15 um with a bandwidth <5x10-5cm-1, is employed as tunable IR light source. A hardware-based (boxcar integrator) multi-trigger and timing scheme recently reported by Zhao et al. (2013CPL...565..132Z) is used to apply cw-CRDS to the pulsed plasma. In the present experiment, typical ring-down time values are ~8-10 us, corresponding to a detection sensitivity, i.e., noise equivalent absorption, of up to ~2x10-7 per centimeter for the 3 cm long plasma jet. (1 data file).

  5. 14C tebuconazole degradation in Colombian soils.

    PubMed

    Mosquera, C S; Martínez, M J; Guerrero, J A

    2010-01-01

    Tebuconazole is a fungicide used on onion crops (Allium Fistulosum L) in Colombia. Persistence of pesticides in soils is characterized by the half-life (DT50), which is influenced by their chemical structure, the physical and chemical properties of the soil and the previous soil history. Based on its structural and chemical properties, tebuconazole should be expected to be relatively persistent in soils. Laboratory incubation studies were conducted to evaluate persistence and bond residues of 14C tebuconazole in three soils, two inceptisol (I) and one histosol (H). Textural classifications were: loam (101), loamy sand (102) and loam (H03), respectively. Data obtained followed a first-order degradation kinetics (R2 > or = 0.899) with DT50 values between 158 and 198 days. The production of 14CO2 from the 14C-ring-labelled test chemicals was very low and increased slightly during 63 days in all cases. The methanol extractable 14C-residues were higher than aqueous ones and both decreased over incubation time for the three soils. The formation of bound 14C-residues increased with time and final values were 11.3; 5.55 and 7.87% for 101, 102 and H03 respectively. Soil 101 showed the lowest mineralization rate and the highest bound residues formation, which might be explained by the clay fraction content. In contrast, an inverse behavior was found for soils 102 and H03, these results might be explained by the higher soil organic carbon content.

  6. Autoradiographic distribution of /sup 14/C-labeled 3H-imidazo(4,5-f)quinoline-2-amines in mice

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

    Bergman, K.

    1985-03-01

    The highly mutagenic heterocyclic amines, 2-amino-3-methylimidazo(4,5-f)quinoline (IQ) and 2-amino-3,4-dimethylimidazo(4,5-f)quinoline (MeIQ), are formed during heating of protein-rich foods. In order to gain information about the distribution and fate of IQ and MeIQ in vivo, a whole-body autoradiographic study of i.v.-injected /sup 14/C-labeled IQ and MeIQ has been performed in male NMRI, pregnant NMRI, and female C3H mice. IQ and MeIQ showed similar distribution patterns. At short survival times, the autoradiograms were characterized by an accumulation of radioactivity in metabolic and excretory organs (liver, kidney, bile, urine, gastric and intestinal contents, salivary glands, nasal mucosa, and Harder's gland), as well as inmore » lymphomyeloid tissues (bone marrow, thymus, spleen and lymph nodes) and in endocrine and reproductive tissues (adrenal medulla, pancreatic islets, thyroid, hypophysis, testis, epididymis, seminal vesicles, ampulla, and prostate). The liver and kidney cortex were identified as sites of retention of nonextractable radioactivity. IQ and MeIQ showed a strong affinity for melanin. IQ and MeIQ passed the placenta, but no radioactivity was retained in fetal tissues. The results pinpoint the liver as a site of IQ- and MeIQ-mediated toxicity. Future studies of IQ and MeIQ may be guided by and clarify the role of other tissue localizations in the toxicity of IQ and MeIQ.« less

  7. Estimating the impact from Fukushima in Southern Spain by 131I and Accelerator Mass Spectrometry detection of 129I.

    PubMed

    Gómez-Guzmán, J M; López-Gutiérrez, J M; García-Tenorio, R; Agulló, L; Peruchena, J I; Manjón, G; García-León, M

    2017-01-01

    After the Fukushima accident, large amounts of radionuclides were discharged to the atmosphere. Some of them travelled long distances and were detected in places as far from Japan as Spain a few days after the accident. One of these radionuclides was 131 I. Its isotope 129 I (T1/2 = 15.7 × 106 years) was also expected to follow the same pathway. In this work, we present the results for the 129 I concentration in the same atmospheric samples from Seville (Spain) where 131 I activity was measured in 2011 by Baeza et al. (2012). 129 I concentrations in aerosol and gaseous samples showed concentrations in the order of 104 and 105 atoms/m 3 , typically higher in the gaseous form with respect to the aerosol form. Also 129 I in rainwater was measured, showing concentrations in the order of 10 8  atoms/L. The results show a very good agreement with the 131 I profile, showing that, if background from other sources is not relevant, it is possible to estimate the impact of similar events years after them thanks to the sensitivity of techniques like Accelerator Mass Spectrometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Detection of recycled marine sediment components in crater lake fluids using 129I

    NASA Astrophysics Data System (ADS)

    Fehn, U.; Snyder, G. T.; Varekamp, J. C.

    2002-06-01

    Crater lakes provide time-integrated samples of volcanic fluids, which may carry information on source components. We tested under what circumstances 129I concentrations can be used for the detection of a signal derived from the recycling of marine sediments in subduction zone magmatism. The 129I system has been successfully used to determine origin and pathways in other volcanic fluids, but the application of this system to crater lakes is complicated by the presence of anthropogenic 129I, related to recent nuclear activities. Results are reported from four crater lakes, associated with subducting crust varying in age between 23 and 98 Ma. The 129I/I ratios determined for Copahue, Argentina, (129I/I=700×10-15) and White Island, New Zealand, (129I/I=284×10-15) demonstrate the presence of iodine in the crater lakes that was derived from recycled marine sediments. A comparison to the ages of the subducted sediments in these two cases indicates that the ratios likely reflect iodine remobilization from the entire sediment column that was undergoing subduction. While the 129I signals in Poás and Rincón de la Vieja, Costa Rica also demonstrate the presence of recycled iodine, the relatively high percentage of meteoric water in these lakes prevents a reliable determination of source ages. The observed high concentrations of iodine and 129I/I ratios substantially below current surface values strongly argue for the presence of recycled marine components in the arc magmas of all four cases. Components from subducted marine sediments can be quantified and related to specific parts of the sediment column in cases where the iodine concentration in the lake waters exceeds 5 μM.

  9. Regulator-dependent mechanisms of C3b processing by factor I allow differentiation of immune responses.

    PubMed

    Xue, Xiaoguang; Wu, Jin; Ricklin, Daniel; Forneris, Federico; Di Crescenzio, Patrizia; Schmidt, Christoph Q; Granneman, Joke; Sharp, Thomas H; Lambris, John D; Gros, Piet

    2017-08-01

    The complement system labels microbes and host debris for clearance. Degradation of surface-bound C3b is pivotal to direct immune responses and protect host cells. How the serine protease factor I (FI), assisted by regulators, cleaves either two or three distant peptide bonds in the CUB domain of C3b remains unclear. We present a crystal structure of C3b in complex with FI and regulator factor H (FH; domains 1-4 with 19-20). FI binds C3b-FH between FH domains 2 and 3 and a reoriented C3b C-terminal domain and docks onto the first scissile bond, while stabilizing its catalytic domain for proteolytic activity. One cleavage in C3b does not affect its overall structure, whereas two cleavages unfold CUB and dislodge the thioester-containing domain (TED), affecting binding of regulators and thereby determining the number of cleavages. These data explain how FI generates late-stage opsonins iC3b or C3dg in a context-dependent manner, to react to foreign, danger or healthy self signals.

  10. Glass-bonded iodosodalite waste form for immobilization of 129I

    NASA Astrophysics Data System (ADS)

    Chong, Saehwa; Peterson, Jacob A.; Riley, Brian J.; Tabada, Diana; Wall, Donald; Corkhill, Claire L.; McCloy, John S.

    2018-06-01

    Immobilization of radioiodine is an important requirement for current and future nuclear fuel cycles. Iodosodalite [Na8(AlSiO4)6I2] was synthesized hydrothermally from metakaolin, NaI, and NaOH. Dried unwashed sodalite powders were used to synthesize glass-bonded iodosodalite waste forms (glass composite materials) by heating pressed pellets at 650, 750, or 850 °C with two types of sodium borosilicate glass binders. These heat-treated specimens were characterized with X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, thermal analysis, porosity and density measurements, neutron activation analysis, and inductively-coupled plasma mass spectrometry. For the best waste form produced (pellets mixed with 10 mass% of glass binder and heat-treated at 750 °C), the maximum possible elemental iodine loading was 19.8 mass%, but only ∼8-9 mass% waste loading of iodine was retained in the waste form after thermal processing. Other pellets with higher iodine retention either contained higher porosity or were incompletely sintered. ASTM C1308 and C1285 (product consistency test, PCT) experiments were performed to understand chemical durability under diffusive and static conditions. The C1308 test resulted in significantly higher normalized loss compared to the C1285 test, most likely because of the strong effect of neutral pH solution renewal and prevention of ion saturation in solution. Both experiments indicated that release rates of Na and Si were higher than for Al and I, probably due to a poorly durable Na-Si-O phase from the glass bonding matrix or from initial sodalite synthesis; however the C1308 test result indicated that congruent dissolution of iodosodalite occurred. The average release rates of iodine obtained from C1308 were 0.17 and 1.29 g m-2 d-1 for 80 or 8 m-1, respectively, and the C1285 analysis gave a value of 2 × 10-5 g m-2 d-1, which is comparable to or better than the durability of

  11. Detections of Long Carbon Chains CH_{3}CCCCH, C_{6}H, LINEAR-C_{6}H_{2} and C_{7}H in the Low-Mass Star Forming Region L1527

    NASA Astrophysics Data System (ADS)

    Araki, Mitsunori; Takano, Shuro; Sakai, Nami; Yamamoto, Satoshi; Oyama, Takahiro; Kuze, Nobuhiko; Tsukiyama, Koichi

    2017-06-01

    Carbon chains in the warm carbon chain chemistry (WCCC) region has been searched in the 42-44 GHz region by using Green Bank 100 m telescope. Long carbon chains C_{7}H, C_{6}H, CH_{3}CCCCH, and linear-C_{6}H_{2} and cyclic species C_{3}H and C_{3}H_{2}O have been detected in the low-mass star forming region L1527, performing the WCCC. C_{7}H was detected for the first time in molecular clouds. The column density of C_{7}H is derived to be 6.2 × 10^{10} cm^{-2} by using the detected J = 24.5-23.5 and 25.5-24.5 rotational lines. The ^{2}Π_{1/2} electronic state of C_{6}H, locating 21.6 K above the ^{2}Π_{3/2} electronic ground state, and the K_a = 0 line of the para species of linear-C_{6}H_{2} were also detected firstly in molecular clouds. The column densities of the ^{2}Π_{1/2} and ^{2}Π_{3/2} states of C_{6}H in L1527 were derived to be 1.6 × 10^{11} and 1.1 × 10^{12} cm^{-2}, respectively. The total column density of linear-C_{6}H_{2} is obtained to be 1.86 × 10^{11} cm^{-2}. While the abundance ratios of carbon chains in between L1527 and the starless dark cloud Taurus Molecular Cloud-1 Cyanopolyyne Peak (TMC-1 CP) have a trend of decrease by extension of carbon-chain length, column densities of CH_{3}CCCCH and C_{6}H are on the trend. However, the column densities of linear-C_{6}H_{2}, and C_{7}H are as abundant as those of TMC-1 CP in spite of long carbon chain, i.e., they are not on the trend. The abundances of linear-C_{6}H_{2} and C_{7}H show that L1527 is rich for long carbon chains as well as TMC-1 CP.

  12. Modelling the activity of 129I in the primary coolant of a CANDU reactor

    NASA Astrophysics Data System (ADS)

    Lewis, Brent J.; Husain, Aamir

    2003-01-01

    A mathematical treatment has been developed to describe the activity levels of 129I as a function of time in the primary heat transport system during constant power operation and for a reactor shutdown situation. The model accounts for a release of fission-product iodine from defective fuel rods and tramp uranium contamination on in-core surfaces. The physical transport constants of the model are derived from a coolant activity analysis of the short-lived radioiodine species. An estimate of 3×10 -9 has been determined for the coolant activity ratio of 129I/ 131I in a CANDU Nuclear Generating Station (NGS), which is in reasonable agreement with that observed in the primary coolant and for plant test resin columns from pressurized and boiling water reactor plants. The model has been further applied to a CANDU NGS, by fitting it to the observed short-lived iodine and long-lived cesium data, to yield a coolant activity ratio of ˜2×10 -8 for 129I/ 137Cs. This ratio can be used to estimate the levels of 129I in reactor waste based on a measurement of the activity of 137Cs.

  13. Synthesis, Structures, and Vibrational Spectroscopy of the Two-Dimensional Iodates Ln(IO) 3 and Ln(IO 3) 3(H 2O) ( Ln-Yb,Lu)

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

    Assefa, Zerihun; Ling, Jie; Haire, Richard

    2006-01-01

    The reaction of Lu3+ or Yb3+ and H5IO6 in aqueous media at 180 C leads to the formation of Yb(IO3)3(H2O) or Lu(IO3)3(H2O), respectively, while the reaction of Yb metal with H5IO6 under similar reaction conditions gives rise to the anhydrous iodate, Yb(IO3)3. Under supercritical conditions Lu3+ reacts with HIO3 and KIO4 to yield the isostructural Lu(IO3)3. The structures have been determined by single-crystal X-ray diffraction. Crystallographic data are (MoKa, {lambda}=0.71073 {angstrom}): Yb(IO3)3, monoclinic, space group P21/n, a=8.6664(9) {angstrom}, b=5.9904(6) {angstrom}, c=14.8826(15) {angstrom}, {beta}=96.931(2){sup o}, V=766.99(13), Z=4, R(F)=4.23% for 114 parameters with 1880 reflections with I>2s(I); Lu(IO3)3, monoclinic, space group P21/n,more » a=8.6410(9), b=5.9961(6), c=14.8782(16) {angstrom}, {beta}=97.028(2){sup o}, V=765.08(14), Z=4, R(F)=2.65% for 119 parameters with 1756 reflections with I>2s(I); Yb(IO3)3(H2O), monoclinic, space group C2/c, a=27.2476(15), b=5.6296(3), c=12.0157(7) {angstrom}, {beta}=98.636(1){sup o}, V=1822.2(2), Z=8, R(F)=1.51% for 128 parameters with 2250 reflections with I>2s(I); Lu(IO3)3(H2O), monoclinic, space group C2/c, a=27.258(4), b=5.6251(7), c=12.0006(16) {angstrom}, {beta}=98.704(2){sup o}, V=1818.8(4), Z=8, R(F)=1.98% for 128 parameters with 2242 reflections with I>2s(I). The f elements in all of the compounds are found in seven-coordinate environments and bridged with monodentate, bidentate, or tridentate iodate anions. Both Lu(IO3)3(H2O) and Yb(IO3)3(H2O) display distinctively different vibrational profiles from their respective anhydrous analogs. Hence, the Raman profile can be used as a complementary diagnostic tool to discern the different structural motifs of the compounds.« less

  14. Hydrocarbon Chemistry in Planetary Nebulae: Observations of CCH and c-C3H2

    NASA Astrophysics Data System (ADS)

    Schmidt, Deborah Rose; Zack, Lindsay; Ziurys, Lucy M.

    2018-06-01

    In an effort to fully evaluate the molecular content of planetary nebulae (PNe), and the role of hydrocarbons, we have undertaken a search for CCH towards K4–47, K3–58, K3–17, M3–28, M4–14, Hb 5, K3-45, M1-7, M3-55, NGC 2440, NGC 6772, M1-12, and M1-20. These nebulae span a range of kinematic ages and morphologies. In addition, we observed CN, CCH, and c-C3H2 at eight positions sampling the Helix Nebula. Measurements at 3 mm of the N=1→0 transitions of CCH and CN and the J=21,2→10,1 of c-C3H2 were performed using the ALMA prototype 12-M antenna of the Arizona Radio Observatory (ARO), while the N=3→2 transition of CCH at 1 mm was observed using the ARO Sub-Millimeter Telescope. CCH was detected in 9 of the 13 survey PNe, while CCH, CN, and c-C3H2 were observed at all positions in the Helix, often with a complex velocity structure; c-C3H2 was also identified in K4-47. From radiative transfer modeling, column densities for CCH were found to range between Ntot(CCH) ~ 0.2-3.3 × 1015 cm-2 for the survey PNe, corresponding to fractional abundances with respect to H2 of f(CCH) ~ 0.2-47 × 10-7. The CN, CCH, and c-C3H2 column densities across the Helix were estimated to range between Ntot(CN) ~ 6.9-74 × 1011 cm-2, Ntot(CCH) ~ 3.2-28 × 1011 cm-2, and Ntot(c-C3H2) ~ 0.2-4.7 × 1011 cm-2, with fractional abundances of f(CN) ~ 0.9-9.8 × 10-7, f(CCH) ~ 0.4-3.7 × 10-7, and f(c-C3H2) ~ 0.3-6.5 × 10-8. Based on HCN measurements of the Helix by Schmidt & Ziurys (2017a), [CN]/[HCN] ratios are ~1-34, while [CCH]/[c-C3H2] ratios varied between ~3-46. The abundance of CCH in all observed PNe did not vary significantly across the nebular lifespan of ~10,000 years, in contrast to model predictions. These abundances are ~1-2 orders of magnitude greater than those measured in the diffuse ISM; moreover, the [CN]/[HCN] and [CCH]/[c-C3H2] ratios observed in the Helix are comparable to those in diffuse clouds, striking evidence that molecular material ejected from PNe

  15. Metabolism of 14C-azoxystrobin in water at different pH.

    PubMed

    Singh, Neera; Singh, Shashi B; Mukerjee, Irani; Gupta, Suman; Gajbhiye, Vijay T; Sharma, Praveen K; Goel, Mayurika; Dureja, Prem

    2010-02-01

    Metabolism of (14)C-azoxystrobin was studied in water at pH 4, 7 and 9. The study suggested that volatilization losses of azoxystrobin were very low (3%) during 130 days of incubation. Only 2.5-4.2% of azoxystrobin was mineralised to CO(2) and pH of water did not have much effect on rate of mineralisation. The dissipation of azoxystrobin in water of all the three pHs followed first order kinetic with half-life values ranging from 143 to 158 d; degradation was the fastest at pH 9. Azoxystrobin acid, a major metabolite, was detected 4-7 day onwards and its concentration increased up to 130 days. The formation of azoxystrobin acid was more and faster under alkaline (pH 9) condition than neutral (pH 7) or acidic (pH 4) conditions.

  16. 3,4-Dimethyl-1-phenyl­pyrano[2,3-c]pyrazol-6(1H)-one

    PubMed Central

    Ahmad, Neman; Tahir, M. Nawaz; Khan, Misbahul Ain; Ather, Abdul Qayyum; Khan, Muhammad Naeem

    2011-01-01

    In the title compound, C14H12N2O2, the dihedral angle between the phenyl ring and the 3,4-dimethyl­pyrano[2,3-c]pyrazol-6(1H)-one system is 7.28 (6)°. An intra­molecular C—H⋯O inter­action generates an S(6) ring. In the crystal, the mol­ecules are linked by C—H⋯O hydrogen bonds, forming C(8) chains. C–H⋯π and π–π inter­actions [centroid–centroid separation = 3.6374 (12) Å] further consolidate the packing. PMID:21754037

  17. Entry of (/sup 3/H)water and (1,2-/sup 14/C)polyethylene glycol 4000 into normal and cystic fibrosis salivary mucus

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

    Lukie, B.E.

    1983-03-01

    This investigation was performed to compare the entry of (/sup 3/H)water and (/sup 14/C)PEG into samples of salivary mucus from patients with CF and normal subjects. A solution containing both radioisotopes was added to samples and salivary mucus and mixed, and entry of each into mucus was determined by their dilution in the supernatant at 1, 2, 4, and 24 hr. (/sup 3/H)water rapidly entered and equilibrated with the water content of both normal and CF mucus. (/sup 14/C)PEG entered mucus more slowly than (/sup 3/H)water and by 24 hr had entered at a ratio of only 0.794 +/- 0.108more » and 0.766 +/- 0.039 of the water space accessible to (/sup 3/H)water in normal and CF mucus, respectively. The mechanisms responsible for the partial exclusion of the large polyethylene glycol molecule were not explored but may reflect restriction of access to a portion of mucus water. Thus water entry and solute exclusion, both determinants of permeability, were unaltered in CF mucus, which fact provides evidence against the presence of a generalized defect of mucus permeability in this disease. The techniques developed for this study may be adaptable to the study of the permeability properties of mucus from other sources and other gels.« less

  18. Entry of (/sup 3/H)water and (1,2-/sup 14/C)polyethylene glycol 4000 into normal and cystic fibrosis salivary mucus

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

    Lukie, B.E.

    1983-03-01

    This investigation was performed to compare the entry of (/sup 3/H)water and (/sup 14/C)PEG into samples of salivary mucus from patients with CF and normal subjects. A solution containing both radioisotopes was added to samples of salivary mucus and mixed, and entry of each into mucus was determined by their dilution in the supernatant at 1, 2, 4, and 24 hr. (/sup 3/H)water rapidly entered and equilibrated with the water content of both normal and CF mucus. (/sup 14/C)PEG entered mucus more slowly than (/sup 3/H)water and by 24 hr had entered at a ratio of only 0.794 +/- 0.108more » and 0.766 +/- 0.039 of the water space accessible to (/sup 3/H)water in normal and CF mucus, respectively. The mechanisms responsible for the partial exclusion of the large polyethylene glycol molecule were not explored but may reflect steric restriction of access to a portion of mucus water. Thus water entry and solute exclusion, both determinants of permeability, were unaltered in CF mucus, which fact provides evidence against the presence of a generalized defect of mucus permeability in this disease. The techniques developed for this study may be adaptable to the study of the permeability properties of mucus from other sources and other gels.« less

  19. Cyclometalated products of [(COE)(2)RhCl](2) and 1,3-(RSCH(2))(2)C(6)H(4) (R = (t)Bu, (i)Pr) Are Dimeric. Synthesis, molecular structures, and solution dynamics of [mu-ClRh(H)(RSCH(2))(2)C(6)H(3)-2,6](2).

    PubMed

    Evans, Daniel R; Huang, Mingsheng; Seganish, W Michael; Chege, Esther W; Lam, Yiu-Fai; Fettinger, James C; Williams, Tracie L

    2002-05-20

    Two tridentate thioether pincer ligands, 1,3-(RSCH(2))(2)C(6)H(4) (R = (t)()Bu, 1a; R = (i)()Pr, 1b) underwent cyclometalation using [(COE)(2)RhCl](2) in air/moisture-free benzene at room temperature. The resultant complexes, [mu-ClRh(H)(RSCH(2))(2)C(6)H(3)-2,6](2) (R = (t)Bu, 2a; R = (i)Pr, 2b) are dimeric both in the solid state and in solution. A battery of variable-temperature one- and two-dimensional (1)H NMR experiments showed conclusively that both complexes undergo dynamic exchange in solution. Exchange between two dimeric diastereomers of 2a in solution occurred via rotation about the Rh-C(ipso) bond. The dynamic exchange of 2b was significantly more complex as an additional exchange mechanism, sulfur inversion, occurred, which resulted in the exchange between several diastereomers in solution.

  20. Glucose turnover in kelp bass (Paralabrax sp. ): in vivo studies with (6-/sup 3/H,6-/sup 14/C)glucose

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

    Bever, K.; Chenoweth, M.; Dunn, A.

    1977-01-01

    (6-/sup 3/H,6-/sup 14/C)glucose was injected via an indwelling arterial cannula in free-swimming, fed, and fasted kelp bass to determine hepatic glucose production, peripheral glucose uptake, minimal glucose mass, mean transit time, and the percent of carbon recycling under the two different nutritional states. Mean plasma glucose levels remained unchanged in fed and fasted fish (48 +- 8 vs. 43 +- 8 mg/100 ml). During steady-state conditions, glucose replacement rates of fed and fasted fish determined with (6-/sup 3/H)glucose are similar (0.035 +- 0.006 vs. 0.025 +- 0.003 mg/min per 100 g) and do not differ from rates determined with (6-/supmore » 14/C)glucose (0.035 +- 0.005 vs. 0.026 +- 0.002). The minimal glucose masses and the mean transit times determined with both isotopes are also similar suggesting that plasma glucose levels and glucose turnover are maintained in fish fasted up to 40 days with no apparent increase in carbon recycling. Nonsteady-state isotope experiments suggest that these fish can alter rates of hepatic glucose production and peripheral uptake in response to hyper- and hypoglycemia.« less

  1. Energy and Spectroscopic Characterization of the Isomers of C4H3-, C6H3-, and C6H5-

    NASA Technical Reports Server (NTRS)

    Wright, Danielle; Bera, Partha P.; Lee, Timothy J.

    2015-01-01

    Organic and inorganic molecules, neutral and ions have been observed in the interstellar medium. A few anions of organic molecules have also been observed recently. The Cassini spacecraft in the upper atmosphere of Titan has observed anions of large organic molecules. In this project we have studied the physical and spectroscopic properties of C4H3-, C6H3-, and C6H5-. We have optimized the geometrical structures of all low-lying isomers of the anions, calculated rotational, and harmonic vibrational frequencies of the anions mentioned above using the B3LYP density functional along with the augmented correlation consistent polar valence triple zeta (aug-cc-pVTZ) basis set. We have found many low-lying isomers on the potential energy surface of these anions.

  2. The Polyadenosine RNA-binding Protein, Zinc Finger Cys3His Protein 14 (ZC3H14), Regulates the Pre-mRNA Processing of a Key ATP Synthase Subunit mRNA*

    PubMed Central

    Wigington, Callie P.; Morris, Kevin J.; Newman, Laura E.; Corbett, Anita H.

    2016-01-01

    Polyadenosine RNA-binding proteins (Pabs) regulate multiple steps in gene expression. This protein family includes the well studied Pabs, PABPN1 and PABPC1, as well as the newly characterized Pab, zinc finger CCCH-type containing protein 14 (ZC3H14). Mutations in ZC3H14 are linked to a form of intellectual disability. To probe the function of ZC3H14, we performed a transcriptome-wide analysis of cells depleted of either ZC3H14 or the control Pab, PABPN1. Depletion of PABPN1 affected ∼17% of expressed transcripts, whereas ZC3H14 affected only ∼1% of expressed transcripts. To assess the function of ZC3H14 in modulating target mRNAs, we selected the gene encoding the ATP synthase F0 subunit C (ATP5G1) transcript. Knockdown of ZC3H14 significantly reduced ATP5G1 steady-state mRNA levels. Consistent with results suggesting that ATP5G1 turnover increases upon depletion of ZC3H14, double knockdown of ZC3H14 and the nonsense-mediated decay factor, UPF1, rescues ATP5G1 transcript levels. Furthermore, fractionation reveals an increase in the amount of ATP5G1 pre-mRNA that reaches the cytoplasm when ZC3H14 is depleted and that ZC3H14 binds to ATP5G1 pre-mRNA in the nucleus. These data support a role for ZC3H14 in ensuring proper nuclear processing and retention of ATP5G1 pre-mRNA. Consistent with the observation that ATP5G1 is a rate-limiting component for ATP synthase activity, knockdown of ZC3H14 decreases cellular ATP levels and causes mitochondrial fragmentation. These data suggest that ZC3H14 modulates pre-mRNA processing of select mRNA transcripts and plays a critical role in regulating cellular energy levels, observations that have broad implications for proper neuronal function. PMID:27563065

  3. Near-conservative behavior of 129Iodine in the Orange County Aquifer System, California

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

    Schwer, K A; Santschi, P H; Moran, J E

    Iodine is a biophilic element, with one stable isotope, {sup 127}I, and one long-lived radioisotope, {sup 129}I, which originates in the surface environment almost entirely from anthropogenic activities such as nuclear fuel reprocessing. Very few studies have evaluated the geochemical behavior of iodine isotopes in the subsurface. The concentrations of {sup 129}I and {sup 127}I were measured in wells fed by a series of artificial recharge ponds in the Forebay Area of the Orange County groundwater basin (California, USA) to evaluate their potential use as hydrological tracers. To substantiate interpretation of {sup 129}I and {sup 127}I concentration data, the aquifermore » system was evaluated using literature values of aquifer water mass age based on {sup 3}H/{sup 3}He, Xenon and {delta}{sup 18}O tracer data, as well as time-series data of Santa Ana River flow rates over the past decade. The aquifer data demonstrate the nearly conservative behavior of {sup 129}I, with {sup 129}I/{sup 127}I ratios likely reflecting variations in source functions as well as climatic conditions, and with inferred particle-water partition coefficients (K{sub d}) of 0.1 cm{sup 3} g{sup -1} or less.« less

  4. β-Selective C-H arylation of pyrroles leading to concise syntheses of lamellarins C and I.

    PubMed

    Ueda, Kirika; Amaike, Kazuma; Maceiczyk, Richard M; Itami, Kenichiro; Yamaguchi, Junichiro

    2014-09-24

    The first general β-selective C-H arylation of pyrroles has been developed by using a rhodium catalyst. This C-H arylation reaction, which is retrosynthetically straightforward but results in unusual regioselectivity, could result in de novo syntheses of pyrrole-derived natural products and pharmaceuticals. As such, we have successfully synthesized polycyclic marine pyrrole alkaloids, lamellarins C and I, by using this β-selective arylation of pyrroles with aryl iodides (C-H/C-I coupling) and a new double C-H/C-H coupling as key steps.

  5. Nqrs Data for H4I3Li2NO9 [H4INO3·2(ILiO3)] (Subst. No. 2278)

    NASA Astrophysics Data System (ADS)

    Chihara, H.; Nakamura, N.

    This document is part of Subvolume B 'Substances Containing C10H16 … Zn' of Volume 48 'Nuclear Quadrupole Resonance Spectroscopy Data' of Landolt-Börnstein - Group III 'Condensed Matter'. It contains an extract of Section '3.2 Data tables' of the Chapter '3 Nuclear quadrupole resonance data' providing the NQRS data for H4I3Li2NO9 [H4INO3·2(ILiO3)] (Subst. No. 2278)

  6. Over Three years of Monitoring 129I spread in Pacific Ocean After the 2011 Fukushima Daiichi Nuclear Power Plant Accident

    NASA Astrophysics Data System (ADS)

    Chang, C. C.; Burr, G.; Jull, A. J. T.; Priyadarshi, A.; Thiemens, M. H.; Biddulph, D.; Russell, J. L.

    2014-12-01

    129I is a long-lived radionuclide that has been used as a useful environmental tracer. At present, the global 129I in surface water is about 1-2 orders of magnitude higher than pre-1990 levels. The anthropogenic 129I signal produced from industrial nuclear fuel reprocessing plants is known to be the primary source of 129I in marine surface waters of the Atlantic, and elevated 129I values are found globally. The Great East Japan Earthquake and the induced tsunami in 2011 triggered the nuclear shutdowns, failures, and partial meltdowns of Fukushima Daiichi Nuclear Power Plant. The accident resulted in a series of radioactive material releases into the environment and spread out through atmospheric and ocean circulation. We will present 129I results of water samples collected weekly near Scripps Institution of Oceanography, San Diego, CA for the past 3 years. We also have several measurements collected a year apart from Kaohsiung, Taiwan, which represent west margin of Pacific Ocean, and from Alaska, Washington, and Oregon. By establishing 129I time series, we can observe the spread of 129I in the surface waters of the Pacific Ocean that resulted from the accidental releases.

  7. Vanadium-Catalyzed C(sp3)–H Fluorination Reactions†

    PubMed Central

    Xia, Ji-Bao; Ma, Yuyong; Chen, Chuo

    2014-01-01

    Vanadium(III) oxide catalyzes the direct fluorination of C(sp3)–H groups with Selectfluor. This reaction is operationally simple. The catalyst and the reaction byproduct can be removed easily by filtration. Using this method, a fluorine atom can be introduced to the tertiary position of 1,4-cineole and L-menthone selectively. PMID:24976971

  8. Synthesis and characterization of two novel inorganic/organic hybrid materials based on polyoxomolybdate clusters: (C5H5N5)2(C5H6N5)4[(HAsO4)2Mo6O18]·11H2O and Na2(Himi)3[SeMo6O21(CH3COO)3]·6H2O

    NASA Astrophysics Data System (ADS)

    Ayed, Meriem; Mestiri, Imen; Ayed, Brahim; Haddad, Amor

    2017-01-01

    Two new organic-inorganic hybrid compound, (C5H5N5)2(C5H6N5)4[(HAsO4)2Mo6O18]·11H2O (I) and Na2(Himi)3[SeMo6O21(CH3COO)3]·6H2O (II) were synthesized and structurally characterized by scanning electron microscopy (SEM), elemental analyses, FTIR, UV spectroscopy, thermal stability analysis, XRD and single crystal X-ray diffraction. Crystal data: (I) triclinic system, space group P-1, a = 11,217 (9) Å, b = 11,637 (8) Å, c = 14,919 (8) Å, α = 70,90 (5)°, β = 70,83 (2)°, γ = 62,00(1)° and Z = 1; (II) triclinic system, space group P-1, a = 10.6740(1) Å, b = 10.6740(1) Å, c = 20.0570(1) Å, α = 76.285(1)°, β = 82.198(2)°, γ = 87.075(1)°, Z = 1. The crystal structure of (I) can be described by infinite polyanions [(HAsO4)2Mo6O18]4- organized with water molecules in layers parallel to the c-direction; adjacent layers are further joined up by hydrogen bonding interactions with organic groups which were associated in chains spreading along the b-direction. The structure of (II) consists of functionalized selenomolybdate clusters [SeMo6O21(CH3COO)3]5-, protonated imidazole cations, sodium ions and lattice water molecules, which are held together to generate a three-dimensional supramolecular network via hydrogen-bonding interaction. Furthermore, the electrochemical properties of these compounds have been studied.

  9. Practical Alkoxythiocarbonyl Auxiliaries for Iridium(I)-Catalyzed C-H Alkylation of Azacycles.

    PubMed

    Tran, Anh T; Yu, Jin-Quan

    2017-08-21

    The development of new and practical 3-pentoxythiocarbonyl auxiliaries for Ir I -catalyzed C-H alkylation of azacycles is described. This method allows for the α-C-H alkylation of a variety of substituted pyrrolidines, piperidines, and tetrahydroisoquinolines through alkylation with alkenes. While the practicality of these simple carbamate-type auxiliaries is underscored by the ease of installation and removal, the method's utility is demonstrated in its ability to functionalize biologically relevant l-proline and l-trans-hydroxyproline, delivering unique 2,5-dialkylated amino acid analogues that are not accessible by other C-H functionalization methods. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. A photoelectron spectroscopic investigation of vinyl fluoride (C2H3F): the HeI, threshold and CIS photoelectron spectroscopy

    NASA Astrophysics Data System (ADS)

    Locht, R.; Leyh, B.; Dehareng, D.; Hottmann, K.; Baumgärtel, H.

    2010-01-01

    The threshold photoelectron spectrum (TPES) and the constant ion state (CIS) spectra of the individual ionic states of C2H3F have been recorded using synchrotron radiation. For comparison a well-resolved HeI photoelectron spectrum (HeI-PES) has also been measured and analysed in detail. The TPES has been measured between 9.5 eV and 35 eV photon energy. Numerous vibrational structures, reported for the first time, observed in the ground state and the six excited states of the cation are analysed. Quantum chemical calculations have been performed and provide strong support to the assignments. State-selected CIS spectra highlighted the major importance of autoionization for the production of almost all ionized states of C2H3F observed in this work.

  11. Host-pathogen-interaction reconstituted in 3-dimensional cocultures of mucosa and <i>C. albicansi>.

    PubMed

    Buchs, Romina; Lehner, Bruno; Meuwly, Phillippe; Schnyder, Bruno

    2018-06-14

    <i>C. albicansi> frequently causes recurrent intimal infectious disease (ID). This demands the treatment of multiple phases of the infection. The objective of this study was to uncover the host-pathogen-interaction using 2D epithelium cell-barrier and 3D subepithelium tissue cells of human mucosa. The 2D cell cultures assessed <i>C. albicansi> adhesion. Addition of the anti-fungal drug Fluconazol did not inhibit the adhesion, despite its pathogen growth inhibition (MIC value 0.08μg/mL). A 3D tissue was engineered in multi-transwells by placing human fibroblast cultures on a thick porous scaffold. This contained the yeast placed in the top compartment and prevented passive penetration. After 28h the pathogen transmigrated the barrier and was collected in the bottom compartment. A change in pathogen morphology was observed where hypha formed and grew to be 231μm long after 28h. The hypha was thus long enough to cross the 200μm thick 3D tissue. The 3D infection was inhibited by addition of Fluconazol (0.08μg/mL), confirming that penetration is dependent on pathogen growth. In conclusion, ID was reconstituted step-by-step on 2D epithelium surface and in 3D connective tissue of human mucosa. Fluconazol growth-inhibition of the pathogen <i>C. albicansi> was confirmed in the 3D tissue. We thus propose that this ID <i>in vitroi> test is suitable for the identification and characterization of new treatments against <i>C. albicans.i>.

  12. Electronic absorption spectroscopy of matrix-isolated polycyclic aromatic hydrocarbon cations. II. The phenanthrene cation (C14H10+) and its 1-methyl derivative

    NASA Technical Reports Server (NTRS)

    Salama, F.; Joblin, C.; Allamandola, L. J.

    1994-01-01

    The ultraviolet, visible, and near infrared absorption spectra of phenanthrene (C14H10), 1-methylphenanthrene [(CH3)C14H9], and their radical ions [C14H10+; (CH3)C14H9+], formed by vacuum-ultraviolet irradiation, were measured in neon matrices at 4.2 K. The associated vibronic band systems and their spectroscopic assignments are discussed. The oscillator strengths were calculated for the phenanthrene ion and found lower than the theoretical predictions. This study presents the first spectroscopic data for phenanthrene and its methyl derivative trapped in a neon matrix where the perturbation of the isolated species by its environment is minimum; a condition crucial to astrophysical applications.

  13. Recent evolution of 129I levels in the Nordic Seas and the North Atlantic Ocean.

    PubMed

    Vivo-Vilches, Carlos; López-Gutiérrez, José María; Periáñez, Raúl; Marcinko, Charlotte; Le Moigne, Frédéric; McGinnity, Paul; Peruchena, Juan Ignacio; Villa-Alfageme, María

    2018-04-15

    Most of the anthropogenic radionuclide 129 I released to the marine environment from the nuclear fuel reprocessing plants (NFRP) at Sellafield (England) and La Hague (France) is transported to the Arctic Ocean via the North Atlantic Current and the Norwegian Coastal Current. 129 I concentrations in seawater provides a powerful and well-established radiotracer technique to provide information about the mechanisms which govern water mass transport in the Nordic Seas and the Arctic Ocean and is gaining importance when coupled with other tracers (e.g. CFC, 236 U). In this work, 129 I concentrations in surface and depth profiles from the Nordic Seas and the North Atlantic (NA) Ocean collected from four different cruises between 2011 and 2012 are presented. This work allowed us to i) update information on 129 I concentrations in these areas, required for the accurate use of 129 I as a tracer of water masses; and ii) investigate the formation of deep water currents in the eastern part of the Nordic Seas, by the analysis of 129 I concentrations and temperature-salinity (T-S) diagrams from locations within the Greenland Sea Gyre. In the Nordic Seas, 129 I concentrations in seawater are of the order of 10 9 at·kg -1 , one or two orders of magnitude higher than those measured at the NA Ocean, not so importantly affected by the releases from the NFRP. 129 I concentrations of the order of 10 8 atoms·kg -1 at the Ellet Line and the PAP suggest a direct contribution from the NFRP in the NA Ocean. An increase in the concentrations in the Nordic Seas between 2002 and 2012 has been detected, which agrees with the temporal evolution of the 129 I liquid discharges from the NFRPs in years prior to this. Finally, 129 I profile concentrations, 129 I inventories and T-S diagrams suggest that deep water formation occurred in the easternmost area of the Nordic Seas during 2012. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Isolation and characterization of nonhistone chromosomal protein C-14 which stimulates RNA synthesis.

    PubMed

    James, G T; Yeoman, L C; Matsui, S i; Goldberg, A H; Busch, H

    1977-05-31

    The nonhistone chromatin protein, C-14, was extracted from chromatin of Novikoff hepatoma ascites cells and isolated in high purity as shown by its migration as a single dense spot on two-dimensional polyacrylamide gels. Its mobility on sodium dodecyl sulfate gels is consistent with a molecular weight of approximately 70 000. The amino acid composition shows that protein C-14 has an acidic:basic amino acid ratio of 1.8. Its amino terminal amino acid is lysine. Protein C-14 stimulated the incorporation of [3H]UMP into RNA by approximately 30% when added to naked DNA and homologous RNA polymerase I. A 30% stimulation of [3H]UMP incorporation into RNA was also found when protein C-14 was added to an E. coli RNA polymerase system containing either E. coli or Novikoff hepatoma DNA.

  15. Separation of Long-Lived Fission Products Tc-99 and I-129 from Synthetic Effluents by Crown Ethers

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

    Paviet-Hartmann, P.; Hartmann, T.

    2006-07-01

    To minimize significantly the radio-toxic inventory of nuclear geological repositories to come as well as to reduce the potential of radionuclides migration and to minimize long-term exposure, the concept of partitioning and transmutation (P/T) of nuclear waste is currently discussed. Transmutation offers the possibility to convert radio-toxic radionuclides with long half-lives into radionuclides of shorter half-lives, less toxic isotopes, or even into stable isotopes. Besides the most prominent isotopes of neptunium, plutonium, americium, and curium, the long-lived fission products Tc-99 and I-129 (half-lives of 2.13 x 10{sup 5} years, and 1.57 x 10{sup 7} years, respectively) are promising candidates formore » transmutation in order to prevent their migration from a nuclear repository. Partitioning and transmutation of the most radio-toxic radionuclides will not only minimize the nuclear waste load but most importantly will significantly reduce the long-term radio-toxic hazard of nuclear waste repositories to come. Prior to the deployment of partitioning and transmutation, selective extraction techniques are required to separate the radionuclides of concern. Since the discovery of crown ethers by C. Pedersen, various applications of crown ethers have drawn much attention. Although liquid-liquid extraction of alkali and alkali earth metals by crown ethers has been extensively studied, little data is available on the extraction of Tc-99 and I-129 by crown ethers. The methods developed herein for the specific extraction of Tc-99 and I-129 provide recommendations in support of their selectively extraction from liquid radioactive waste streams, mainly ILW. We report data on the solvent extraction of Tc-99 and I-129 from synthetic effluents by six crown ethers of varying cavity dimensions and derivatization. To satisfy the needs of new extractant systems we are demonstrating that crown ether (CE) based systems have the potential to serve as selective extractants for

  16. Repeated Administration of D-Amphetamine Induces Distinct Alterations in Behavior and Metabolite Levels in 129Sv and Bl6 Mouse Strains.

    PubMed

    Vanaveski, Taavi; Narvik, Jane; Innos, Jürgen; Philips, Mari-Anne; Ottas, Aigar; Plaas, Mario; Haring, Liina; Zilmer, Mihkel; Vasar, Eero

    2018-01-01

    The main goal of the study was to characterize the behavioral and metabolomic profiles of repeated administration (for 11 days) of d-amphetamine (AMPH, 3 mg/kg i. p.), indirect agonist of dopamine (DA), in widely used 129S6/SvEvTac (129Sv) and C57BL/6NTac (Bl6) mouse strains. Acute administration of AMPH (acute AMPH) induced significantly stronger motor stimulation in Bl6. However, repeated administration of AMPH (repeated AMPH) caused stronger motor sensitization in 129Sv compared acute AMPH. Body weight of 129Sv was reduced after repeated saline and AMPH, whereas no change occurred in Bl6. In the metabolomic study, acute AMPH induced an elevation of isoleucine and leucine, branched chain amino acids (BCAA), whereas the level of hexoses was reduced in Bl6. Both BCAAs and hexoses remained on level of acute AMPH after repeated AMPH in Bl6. Three biogenic amines [asymmetric dimethylarginine (ADMA), alpha-aminoadipic acid (alpha-AAA), kynurenine] were significantly reduced after repeated AMPH. Acute AMPH caused in 129Sv a significant reduction of valine, lysophosphatidylcholines (lysoPC a C16:0, lysoPC a C18:2, lysoPC a C20:4), phosphatidylcholine (PC) diacyls (PC aa C34:2, PC aa C36:2, PC aa C36:3, PC aa C36:4) and alkyl-acyls (PC ae C38:4, PC ae C40:4). However, repeated AMPH increased the levels of valine and isoleucine, long-chain acylcarnitines (C14, C14:1-OH, C16, C18:1), PC diacyls (PC aa C38:4, PC aa C38:6, PC aa C42:6), PC acyl-alkyls (PC ae C38:4, PC ae C40:4, PC ae C40:5, PC ae C40:6, PC ae C42:1, PC ae C42:3) and sphingolipids [SM(OH)C22:1, SM C24:0] compared to acute AMPH in 129Sv. Hexoses and kynurenine were reduced after repeated AMPH compared to saline in 129Sv. The established changes probably reflect a shift in energy metabolism toward lipid molecules in 129Sv because of reduced level of hexoses. Pooled data from both strains showed that the elevation of isoleucine and leucine was a prominent biomarker of AMPH-induced behavioral sensitization

  17. Iodine-129 measurements in soil samples from Dolon village near the Semipalatinsk nuclear test site.

    PubMed

    Endo, Satoru; Tomita, Junpei; Tanaka, Kenichi; Yamamoto, Masayoshi; Fukutani, Satoshi; Imanaka, Tetsuji; Sakaguchi, Aya; Amano, Hikaru; Kawamura, Hidehisa; Kawamura, Hisao; Apsalikov, Kazbek N; Gusev, Boris I; Whitehead, Neil E; Shinkarev, Sergey; Hoshi, Masaharu

    2008-07-01

    Dolon village, located about 60 km from the border of the Semipalatinsk nuclear test site, is known to be heavily contaminated by the first USSR atomic bomb test in August 1949. Soil samples around Dolon were taken in October 2005 in an attempt to evaluate internal thyroid dose arising from incorporation of radioiodine isotopes (mainly (131)I). Iodine-129 in soil was measured by using the technique of accelerator mass spectrometry. The (129)I/(127)I atom ratios measured were in the range from 3.3 x 10(-9) to 3.3 x 10(-7). These values were within the range of the current background level ( approximately 10(-9) to 10(-7)) in the environment, including contributions from the global fallout of atmospheric nuclear tests and local fallout of nuclear facilities. The (129)I atom accumulated level in soil ranged from 1.28 x 10(13) to 1.59 x 10(14) atoms m(-2), the average (8.0 x 10(13)) of which was higher than the background level of (2-5) x 10(13). From the relationship between (129)I and( 137)Cs (corrected for background and decay from 1949 to 2005) accumulated levels, the background level of (129)I and the (129)I/(137)Cs ratio around Dolon were estimated to be (6.4 +/- 0.4) x 10(13) atoms m(-2) and 0.25 +/- 0.16, respectively. This (129)I/(137)Cs ratio is almost similar to the fission yield ratio for (239)Pu fast fission (0.24).

  18. Calculational and Experimental Investigations of the Pressure Effects on Radical - Radical Cross Combinations Reactions: C2H5 + C2H3

    NASA Technical Reports Server (NTRS)

    Fahr, Askar; Halpern, Joshua B.; Tardy, Dwight C.

    2007-01-01

    Pressure-dependent product yields have been experimentally determined for the cross-radical reaction C2H5 + C2H3. These results have been extended by calculations. It is shown that the chemically activated combination adduct, 1-C4H8*, is either stabilized by bimolecular collisions or subject to a variety of unimolecular reactions including cyclizations and decompositions. Therefore the "apparent" combination/disproportionation ratio exhibits a complex pressure dependence. The experimental studies were performed at 298 K and at selected pressures between about 4 Torr (0.5 kPa) and 760 Torr (101 kPa). Ethyl and vinyl radicals were simultaneously produced by 193 nm excimer laser photolysis of C2H5COC2H3 or photolysis of C2H3Br and C2H5COC2H5. Gas chromatograph/mass spectrometry/flame ionization detection (GC/MS/FID) were used to identify and quantify the final reaction products. The major combination reactions at pressures between 500 (66.5 kPa) and 760 Torr are (1c) C2H5 + C2H3 yields 1-butene, (2c) C2H5 + C2H5 yields n-butane, and (3c) C2H3 + C2H3 yields 1,3-butadiene. The major products of the disproportionation reactions are ethane, ethylene, and acetylene. At moderate and lower pressures, secondary products, including propene, propane, isobutene, 2-butene (cis and trans), 1-pentene, 1,4-pentadiene, and 1,5-hexadiene are also observed. Two isomers of C4H6, cyclobutene and/or 1,2-butadiene, were also among the likely products. The pressure-dependent yield of the cross-combination product, 1-butene, was compared to the yield of n-butane, the combination product of reaction (2c), which was found to be independent of pressure over the range of this study. The [ 1-C4H8]/[C4H10] ratio was reduced from approx.1.2 at 760 Torr (101 kPa) to approx.0.5 at 100 Torr (13.3 kPa) and approx.0.1 at pressures lower than about 5 Torr (approx.0.7 kPa). Electronic structure and RRKM calculations were used to simulate both unimolecular and bimolecular processes. The relative importance

  19. Dynamics of the C/H and C/F exchanges in the reaction of 3P carbon atoms with vinyl fluoride

    NASA Astrophysics Data System (ADS)

    Lee, Shih-Huang; Chen, Wei-Kan; Chin, Chih-Hao; Huang, Wen-Jian

    2013-08-01

    Two product channels C3H2F + H and C3H3 + F were identified in the reaction of C(3P) atoms with vinyl fluoride (C2H3F) at collision energy 3.7 kcal mol-1 in a crossed molecular-beam apparatus using selective photoionization. Time-of-flight (TOF) spectra of products C3H2F and C3H3 were measured at 12-16 laboratory angles as well as a TOF spectrum of atomic F, a counter part of C3H3, was recorded at single laboratory angle. From the best simulation of product TOF spectra, translational-energy distributions at seven scattering angles and a nearly isotropic (forward and backward peaked) angular distribution were derivable for exit channel C3H2F + H (C3H3 + F) that has average kinetic-energy release of 14.5 (4.9) kcal mol-1. Products C3H2F + H and C3H3 + F were estimated to have a branching ratio of ˜53:47. Furthermore, TOF spectra and photoionization spectra of products C3H2F and C3H3 were measured at laboratory angle 62° with photoionization energy ranging from 7 eV to 11.6 eV. The appearance of TOF spectra is insensitive to photon energy, implying that only single species overwhelmingly contributes to products C3H2F and C3H3. HCCCHF (H2CCCH) was identified as the dominant species based on the measured ionization threshold of 8.3 ± 0.2 (8.6 ± 0.2) eV and the maximal translational-energy release. The C/H and C/F exchange mechanisms are stated.

  20. Histone H3 Lysine 14 (H3K14) Acetylation Facilitates DNA Repair in a Positioned Nucleosome by Stabilizing the Binding of the Chromatin Remodeler RSC (Remodels Structure of Chromatin)*

    PubMed Central

    Duan, Ming-Rui; Smerdon, Michael J.

    2014-01-01

    Histone H3 acetylation is induced by UV damage in yeast and may play an important role in regulating the repair of UV photolesions in nucleosome-loaded genomic loci. However, it remains elusive how H3 acetylation facilitates repair. We generated a strongly positioned nucleosome containing homogeneously acetylated H3 at Lys-14 (H3K14ac) and investigated possible mechanisms by which H3K14 acetylation modulates repair. We show that H3K14ac does not alter nucleosome unfolding dynamics or enhance the repair of UV-induced cyclobutane pyrimidine dimers by UV photolyase. Importantly, however, nucleosomes with H3K14ac have a higher affinity for purified chromatin remodeling complex RSC (Remodels the Structure of Chromatin) and show greater cyclobutane pyrimidine dimer repair compared with unacetylated nucleosomes. Our study indicates that, by anchoring RSC, H3K14 acetylation plays an important role in the unfolding of strongly positioned nucleosomes during repair of UV damage. PMID:24515106

  1. The mitochondrial targeting chaperone 14-3-3ε regulates a RIG-I translocon that mediates membrane-association and innate antiviral immunity

    PubMed Central

    Liu, Helene Minyi; Loo, Yueh-Ming; Horner, Stacy M.; Zornetzer, Gregory A.; Katze, Michael G.; Gale, Michael

    2012-01-01

    Summary RIG-I is a cytosolic pathogen recognition receptor that initiates immune responses against RNA viruses. Upon viral RNA recognition, anti-viral signalling requires RIG-I redistribution from the cytosol to membranes where it binds the adaptor protein, MAVS. Here we identify the mitochondrial targeting chaperone protein, 14-3-3ε, as a RIG-I-binding partner and essential component of a translocation complex or “translocon” containing RIG-I, 14-3-3ε, and the TRIM25 ubiquitin ligase. The RIG-I translocon directs RIG-I redistribution from the cytosol to membranes where it mediates MAVS-dependent innate immune signalling during acute RNA virus infection. 14-3-3ε is essential for the stable interaction of RIG-I with TRIM25, which facilitates RIG-I ubiquitination and initiation of innate immunity against hepatitis C virus and other pathogenic RNA viruses. Our results define 14-3-3ε as a key component of a RIG-I translocon required for innate antiviral immunity. PMID:22607805

  2. The mitochondrial targeting chaperone 14-3-3ε regulates a RIG-I translocon that mediates membrane association and innate antiviral immunity.

    PubMed

    Liu, Helene Minyi; Loo, Yueh-Ming; Horner, Stacy M; Zornetzer, Gregory A; Katze, Michael G; Gale, Michael

    2012-05-17

    RIG-I is a cytosolic pathogen recognition receptor that initiates immune responses against RNA viruses. Upon viral RNA recognition, antiviral signaling requires RIG-I redistribution from the cytosol to membranes where it binds the adaptor protein, MAVS. Here we identify the mitochondrial targeting chaperone protein, 14-3-3ε, as a RIG-I-binding partner and essential component of a translocation complex or "translocon" containing RIG-I, 14-3-3ε, and the TRIM25 ubiquitin ligase. The RIG-I translocon directs RIG-I redistribution from the cytosol to membranes where it mediates MAVS-dependent innate immune signaling during acute RNA virus infection. 14-3-3ε is essential for the stable interaction of RIG-I with TRIM25, which facilitates RIG-I ubiquitination and initiation of innate immunity against hepatitis C virus and other pathogenic RNA viruses. Our results define 14-3-3ε as a key component of a RIG-I translocon required for innate antiviral immunity. Copyright © 2012 Elsevier Inc. All rights reserved.

  3. Novel Helicobacter species H.japonicum isolated from laboratory mice from Japan induces typhlocolitis and lower bowel carcinoma in C57BL/129 IL10−/− mice

    PubMed Central

    Shen, Zeli; Feng, Yan; Muthupalani, Sureshkumar; Sheh, Alexander; Cheaney, Lenzie E.; Kaufman, Christian A.; Gong, Guanyu; Paster, Bruce J.; Fox, James G.

    2016-01-01

    A novel Helicobacter species Helicobacter japonicum was isolated from the stomach and intestines of clinically normal mice received from three institutes from Japan. The novel Helicobacter sp. was microaerobic, grew at 37°C and 42°C, was catalase and oxidase positive, but urease negative. It is most closely related to the 16S rRNA gene of H.muridarum (98.6%); to the 23S rRNA gene of H.hepaticus (97.9%); to the hsp60 gene of H.typhlonius (87%). The novel Helicobacter sp. has in vitro cytolethal distending toxin (CDT) activity; its cdtB gene sequence has 83.8% identity with that of H.hepaticus. The whole genome sequence of H.japonicum MIT 01-6451 has a 2.06-Mb genome length with a 37.5% G + C content. When the organism was inoculated into C57BL/129 IL10−/− mice, it was cultured from the stomach, colon and cecum of infected mice at 6 and 10 weeks post-infection. The cecum had the highest H.japonicum colonization levels by quantitative PCR. The histopathology of the lower bowel was characterized by moderate to severe inflammation, mild edema, epithelial defects, mild to severe hyperplasia, dysplasia and carcinoma. Inflammatory cytokines IFNγ, TNFα and IL17a, as well as iNOS were significantly upregulated in the cecal tissue of infected mice. These results demonstrate that the novel H.japonicum can induce inflammatory bowel disease and carcinoma in IL10−/− mice and highlights the importance of identifying novel Helicobacter spp. especially when they are introduced from outside mouse colonies from different geographic locations. PMID:27655833

  4. CFA-2 and CFA-3 (Coordination Framework Augsburg University-2 and -3); novel MOFs assembled from trinuclear Cu(I)/Ag(I) secondary building units and 3,3',5,5'-tetraphenyl-bipyrazolate ligands.

    PubMed

    Grzywa, Maciej; Geßner, Christof; Denysenko, Dmytro; Bredenkötter, Björn; Gschwind, Fabienne; Fromm, Katharina M; Nitek, Wojciech; Klemm, Elias; Volkmer, Dirk

    2013-05-21

    The syntheses of H2-phbpz, [Cu2(phbpz)]·2DEF·MeOH (CFA-2) and [Ag2(phbpz)] (CFA-3) (H2-phbpz = 3,3',5,5'-tetraphenyl-1H,1'H-4,4'-bipyrazole) compounds and their crystal structures are described. The Cu(I) containing metal-organic framework CFA-2 crystallizes in the tetragonal crystal system, within space group I4(1)/a (no. 88) and the following unit cell parameters: a = 30.835(14), c = 29.306(7) Å, V = 27 865(19) Å(3). CFA-2 features a flexible 3-D three-connected two-fold interpenetrated porous structure constructed of triangular Cu(I) subunits. Upon exposure to different kinds of liquids (MeOH, EtOH, DMF, DEF) CFA-2 shows pronounced breathing effects. CFA-3 crystallizes in the monoclinic crystal system, within space group P2(1)/c (no. 14) and the following unit cell parameters: a = 16.3399(3), b = 32.7506(4), c = 16.2624(3) Å, β = 107.382(2)°, V = 8305.3(2) Å(3). In contrast to the former compound, CFA-3 features a layered 2-D three-connected structure constructed from triangular Ag(i) subunits. Both compounds are characterized by elemental and thermogravimetric analyses, single crystal structure analysis and X-ray powder diffraction, FTIR- and fluorescence spectroscopy. Preliminary results on oxygen activation in CFA-2 are presented and potential improvements in terms of framework robustness and catalytic efficiency are discussed.

  5. Zinc-induced Self-association of Complement C3b and Factor H

    PubMed Central

    Nan, Ruodan; Tetchner, Stuart; Rodriguez, Elizabeth; Pao, Po-Jung; Gor, Jayesh; Lengyel, Imre; Perkins, Stephen J.

    2013-01-01

    The sub-retinal pigment epithelial deposits that are a hallmark of age-related macular degeneration contain both C3b and millimolar levels of zinc. C3 is the central protein of complement, whereas C3u is formed by the spontaneous hydrolysis of the thioester bridge in C3. During activation, C3 is cleaved to form active C3b, then C3b is inactivated by Factor I and Factor H to form the C3c and C3d fragments. The interaction of zinc with C3 was quantified using analytical ultracentrifugation and x-ray scattering. C3, C3u, and C3b associated strongly in >100 μm zinc, whereas C3c and C3d showed weak association. With zinc, C3 forms soluble oligomers, whereas C3u and C3b precipitate. We conclude that the C3, C3u, and C3b association with zinc depended on the relative positions of C3d and C3c in each protein. Computational predictions showed that putative weak zinc binding sites with different capacities exist in all five proteins, in agreement with experiments. Factor H forms large oligomers in >10 μm zinc. In contrast to C3b or Factor H alone, the solubility of the central C3b-Factor H complex was much reduced at 60 μm zinc and even more so at >100 μm zinc. The removal of the C3b-Factor H complex by zinc explains the reduced C3u/C3b inactivation rates by zinc. Zinc-induced precipitation may contribute to the initial development of sub-retinal pigment epithelial deposits in the retina as well as reducing the progression to advanced age-related macular degeneration in higher risk patients. PMID:23661701

  6. Determination of beta emitters ( 90Sr, 14C and 3H) in routine measurements using plastic scintillation beads

    NASA Astrophysics Data System (ADS)

    Tarancón, A.; García, J. F.; Rauret, G.

    2004-01-01

    Plastic scintillation has recently been shown to be a powerful alternative to liquid scintillation and Cherenkov techniques in radionuclide determination due to the good values obtained for the measurement parameters and the low amount of wastes generated. The present study evaluated the capability of plastic scintillation beads and polyethylene vials for routine measurements of beta emitters ( 90Sr, 14C, 3H). Results show that high- and medium-energetic beta emitters can be quantified with relative errors less than 5% in low-activity aqueous samples, whereas low-energetic beta emitters can only be quantified in medium-activity samples.

  7. Use of (2-/sup 14/C)mevalonate and saponin-bound (/sup 14/C)-3-hydroxy-3-methylglutaric acid for the biosynthesis of terpenoids in leaves of Dioscorea deltoidea

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

    Gurielidze, K.G.; Paseshnichenko, V.A.; Vasil'eva, I.S.

    After the introduction of (2-/sup 14/C)acetate into leaves of Dioscorea deltoidea, a radioactive furonanalog of deltafolin - protodeltofolin, containing two-thirds of the label in the 3-hydroxy-3-methylglutaryl portion - was isolated from them. Radioactive ..beta..-careotene and sterols were isolated from cut young leaves of Dioscorea 24 h after the introduction of (/sup 14/C) protodeltofolin into them, using chromatography on a column of silica gel and precipitation of sterols in the form of digitonins for this purpose. The incorporation of radioactivity from (/sup 14/C)-3-hydroxy-3-methyl-glutaric acid, bound in the form of a saponin, and ..beta..-carotene came to 0.18-0.80%, while incorporation into sterols camemore » to 0.07-2.86% of the radioactivity of the alcohol extract. Thereby it was shown that 3-hydroxyl-3-methylglutaric acid, bound in the form of the saponin, can be used to form terpenoids in Dioscorea leaves. It was suggested that the binding of hydroxymethylglutaric acid to saponin represents one of the mechanisms of regulation of the rate of terpenoid biosynthesis in Dioscorea leaves.« less

  8. Studies of the kinetics and thermochemistry of the forward and reverse reaction Cl + C6H6 = HCl + C6H5.

    PubMed

    Alecu, I M; Gao, Yide; Hsieh, P-C; Sand, Jordan P; Ors, Ahmet; McLeod, A; Marshall, Paul

    2007-05-17

    The laser flash photolysis resonance fluorescence technique was used to monitor atomic Cl kinetics. Loss of Cl following photolysis of CCl4 and NaCl was used to determine k(Cl + C6H6) = 6.4 x 10(-12) exp(-18.1 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 578-922 K and k(Cl + C6D6) = 6.2 x 10(-12) exp(-22.8 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 635-922 K. Inclusion of literature data at room temperature leads to a recommendation of k(Cl + C6H6) = 6.1 x 10(-11) exp(-31.6 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) for 296-922 K. Monitoring growth of Cl during the reaction of phenyl with HCl led to k(C6H5 + HCl) = 1.14 x 10(-12) exp(+5.2 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 294-748 K, k(C6H5 + DCl) = 7.7 x 10(-13) exp(+4.9 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 292-546 K, an approximate k(C6H5 + C6H5I) = 2 x 10(-11) cm(3) molecule(-1) s(-1) over 300-750 K, and an upper limit k(Cl + C6H5I) < or = 5.3 x 10(-12) exp(+2.8 kJ mol(-1)/RT) cm(3) molecule(-1) s(-1) over 300-750 K. Confidence limits are discussed in the text. Third-law analysis of the equilibrium constant yields the bond dissociation enthalpy D(298)(C6H5-H) = 472.1 +/- 2.5 kJ mol(-1) and thus the enthalpy of formation Delta(f)H(298)(C6H5) = 337.0 +/- 2.5 kJ mol(-1).

  9. TSO C-129 approvals and anticipated approvals

    DOT National Transportation Integrated Search

    2001-01-01

    This document contains a table of the approvals and anticipated approvals of TSO-C129a equipment (the technical standard order (TSO) for Airborne Supplemental Navigation Equipment Using the Global Positioning System (GPS)). This TSO prescribes the mi...

  10. The H IX galaxy survey - II. H I kinematics of H I eXtreme galaxies

    NASA Astrophysics Data System (ADS)

    Lutz, K. A.; Kilborn, V. A.; Koribalski, B. S.; Catinella, B.; Józsa, G. I. G.; Wong, O. I.; Stevens, A. R. H.; Obreschkow, D.; Dénes, H.

    2018-05-01

    By analysing a sample of galaxies selected from the H I Parkes All Sky Survey (HIPASS) to contain more than 2.5 times their expected H I content based on their optical properties, we investigate what drives these H I eXtreme (H IX) galaxies to be so H I-rich. We model the H I kinematics with the Tilted Ring Fitting Code TiRiFiC and compare the observed H IX galaxies to a control sample of galaxies from HIPASS as well as simulated galaxies built with the semi-analytic model DARK SAGE. We find that (1) H I discs in H IX galaxies are more likely to be warped and more likely to host H I arms and tails than in the control galaxies, (2) the average H I and average stellar column density of H IX galaxies is comparable to the control sample, (3) H IX galaxies have higher H I and baryonic specific angular momenta than control galaxies, (4) most H IX galaxies live in higher spin haloes than most control galaxies. These results suggest that H IX galaxies are H I-rich because they can support more H I against gravitational instability due to their high specific angular momentum. The majority of the H IX galaxies inherits their high specific angular momentum from their halo. The H I content of H IX galaxies might be further increased by gas-rich minor mergers. This paper is based on data obtained with the Australia Telescope Compact Array through the large program C 2705.

  11. 1H NMR relaxometry and quadrupole relaxation enhancement as a sensitive probe of dynamical properties of solids—[C(NH2)3]3Bi2I9 as an example

    NASA Astrophysics Data System (ADS)

    Florek-Wojciechowska, M.; Wojciechowski, M.; Jakubas, R.; Brym, Sz.; Kruk, D.

    2016-02-01

    1H nuclear magnetic resonance relaxometry has been applied to reveal information on dynamics and structure of Gu3Bi2I9 ([Gu = C(NH2)3] denotes guanidinium cation). The data have been analyzed in terms of a theory of quadrupole relaxation enhancement, which has been extended here by including effects associated with quadrupole (14N) spin relaxation caused by a fast fluctuating component of the electric field gradient tensor. Two motional processes have been identified: a slow one occurring on a timescale of about 8 × 10-6 s which has turned out to be (almost) temperature independent, and a fast process in the range of 10-9 s. From the 1H-14N relaxation contribution (that shows "quadrupole peaks") the quadrupole parameters, which are a fingerprint of the arrangement of the anionic network, have been determined. It has been demonstrated that the magnitude of the quadrupole coupling considerably changes with temperature and the changes are not caused by phase transitions. At the same time, it has been shown that there is no evidence of abrupt changes in the cationic dynamics and the anionic substructure upon the phase transitions.

  12. Modeling Surface Water Transport in the Central Pacific Ocean With 129I Records From Coral Skeletons

    NASA Astrophysics Data System (ADS)

    Beck, W.; Biddulph, D. L.; Russell, J. L.; Burr, G. S.; Jull, T. J.; Correge, T.; Roeder, B.

    2008-12-01

    129I occurs naturally in extremely low abundance via cosmic ray interactions in the atmosphere as well as by spontaneous fission of uranium. Oceanic concentrations of 129I have risen by several orders of magnitude during the last half century largely from environmental pollution coming from several point-source nuclear fuel reprocessing plants. In the Pacific basin, much of the increase has apparently come from the Hanford Nuclear reprocessing plant in the United States, with iodine primarily arriving via the Columbia River. Coral skeletons preserve records of 129I concentration of the surface waters from which they were deposited, yielding records with annual resolution or better. We will present three such records from different locations in the Pacific Ocean: the Solomon Islands, Easter Island and Clipperton Atoll. For this study, drill cores from living massive coral skeletons of the species Porites Lobata were collected from these sites. 129I/127I values were measured using accelerator mass spectrometry (AMS) at the University of Arizona with an NEC 3 MV Pelletron accelerator. Results from the analysis of the corals will be compared to the distribution of other mixed-layer tracers (chloro-fluorocarbons and tritium) collected during the World Ocean Circulation Experiment cruises conducted between 1990 and 2002. The 129I/127I records observed in these corals will also be compared to tracer transit time calculations determined from a 20th century simulation of the GFDL coupled-climate passive-tracer model.

  13. WE-AB-202-07: Ventilation CT: Voxel-Level Comparison with Hyperpolarized Helium-3 & Xenon-129 MRI

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

    Tahir, B; Marshall, H; Hughes, P

    Purpose: To compare the spatial correlation of ventilation surrogates computed from inspiratory and expiratory breath-hold CT with hyperpolarized Helium-3 & Xenon-129 MRI in a cohort of lung cancer patients. Methods: 5 patients underwent expiration & inspiration breath-hold CT. Xenon-129 & {sup 1}H MRI were also acquired at the same inflation state as inspiratory CT. This was followed immediately by acquisition of Helium-3 & {sup 1}H MRI in the same breath and at the same inflation state as inspiratory CT. Expiration CT was deformably registered to inspiration CT for calculation of ventilation CT from voxel-wise differences in Hounsfield units. Inspiration CTmore » and the Xenon-129’s corresponding anatomical {sup 1}H MRI were registered to Helium-3 MRI via the same-breath anatomical {sup 1}H MRI. This enabled direct comparison of CT ventilation with Helium-3 MRI & Xenon-129 MRI for the median values in corresponding regions of interest, ranging from finer to coarser in-plane dimensions of 10 by 10, 20 by 20, 30 by 30 and 40 by 40, located within the lungs as defined by the same-breath {sup 1}H MRI lung mask. Spearman coefficients were used to assess voxel-level correlation. Results: The median Spearman’s coefficients of ventilation CT with Helium-3 & Xenon-129 MRI for ROIs of 10 by 10, 20 by 20, 30 by 30 and 40 by 40 were 0.52, 0.56, 0.60 and 0.68 and 0.40, 0.42, 0.52 and 0.70, respectively. Conclusion: This work demonstrates a method of acquiring CT & hyperpolarized gas MRI (Helium-3 & Xenon-129 MRI) in similar breath-holds to enable direct spatial comparison of ventilation maps. Initial results show moderate correlation between ventilation CT & hyperpolarized gas MRI, improving for coarser regions which could be attributable to the inherent noise in CT intensity, non-ventilatory effects and registration errors at the voxel-level. Thus, it may be more beneficial to quantify ventilation at a more regional level.« less

  14. An observational investigation of the identity of B11244 (l-C{sub 3}H{sup +}/C{sub 3}H{sup -})

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

    McGuire, Brett A.; Carroll, P. Brandon; Gratier, Pierre

    Pety et al. have reported the detection of eight transitions of a closed-shell, linear molecule (B11244) in observations toward the Horsehead photodissociation region (PDR), which they attribute to the l-C{sub 3}H{sup +} cation. Recent high-level ab initio calculations have called this assignment into question; the anionic C{sub 3}H{sup –} molecule has been suggested as a more likely candidate. Here, we examine observations of the Horsehead PDR, Sgr B2(N), TMC-1, and IRC+10216 in the context of both l-C{sub 3}H{sup +} and C{sub 3}H{sup –}. We find no observational evidence of K{sub a} = 1 lines, which should be present were themore » carrier indeed C{sub 3}H{sup –}. Additionally, we find a strong anticorrelation between the presence of known molecular anions and B11244 in these regions. Finally, we discuss the formation and destruction chemistry of C{sub 3}H{sup –} in the context of the physical conditions in the regions. Based on these results, we conclude there is little evidence to support the claim that the carrier is C{sub 3}H{sup –}.« less

  15. 3-Methyl-7-(2-thienyl)pyrido[2,3-d]pyrimidine-2,4(1H,3H)-dione: pi-stacked bilayers built from N-H...O, C-H...O and C-H...pi hydrogen bonds.

    PubMed

    Trilleras, Jorge; Quiroga, Jairo; Cobo, Justo; Glidewell, Christopher

    2009-06-01

    In the title compound, C(12)H(9)N(3)O(2)S, the thienyl substituent is disordered over two sets of sites with occupancies of 0.749 (3) and 0.251 (3). A combination of N-H...O, C-H...O and C-H...pi hydrogen bonds links the molecules into bilayers and these bilayers are themselves linked into a continuous structure by pi-pi stacking interactions.

  16. 40 CFR 721.5540 - 1H,3H,5H-oxazolo [3,4-c] oxazole, dihydro-7a-methyl-.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false 1H,3H,5H-oxazolo [3,4-c] oxazole... Specific Chemical Substances § 721.5540 1H,3H,5H-oxazolo [3,4-c] oxazole, dihydro-7a-methyl-. (a) Chemical substances and significant new uses subject to reporting. (1) The chemical substance identified as 1H,3H,5H...

  17. C20H4(C4F8)3: a fluorine-containing annulated corannulene that is a better electron acceptor than C60.

    PubMed

    Kuvychko, Igor V; Dubceac, Cristina; Deng, Shihu H M; Wang, Xue-Bin; Granovsky, Alexander A; Popov, Alexey A; Petrukhina, Marina A; Strauss, Steven H; Boltalina, Olga V

    2013-07-15

    At sixes and sevens: The reaction of corannulene with 35 equivalents of 1,4-C4F8I2 is an efficient and a relatively selective process that yields two main products in which six H atoms are substituted with three C4F8 moieties that form six- and seven-membered rings. Low-temperature photoelectron spectroscopy showed the electron affinity of the major isomer (shown) exceeds that of C60 (2.74±0.02 and 2.689±0.008 eV, respectively). Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Whole-nerve chorda tympani responses to sweeteners in C57BL/6ByJ and 129P3/J mice

    PubMed Central

    Inoue, Masashi; McCaughey, Stuart A.; Bachmanov, Alexander A.; Beauchamp, Gary K.

    2013-01-01

    The C57BL/6ByJ (B6) strain of mice exhibits higher preferences than does the 129P3/J (129) strain for a variety of sweet-tasting compounds. We measured gustatory afferent responses of the whole chorda tympani nerve in these two strains using a broad array of sweeteners and other taste stimuli. Neural responses were greater in B6 than in 129 mice to the sugars sucrose and maltose, the polyol D-sorbitol, and the non-caloric sweeteners NaSaccharin, acesulfame-K, SC-45647, and sucralose. Lower neural response thresholds were also observed in the B6 strain for most of these stimuli. The strains did not differ on their neural responses to amino acids that are thought to taste sweet to mice, with the exception of L-proline, which evoked larger responses in the B6 strain. Aspartame and thaumatin, which taste sweet to humans but are not strongly preferred by B6 or 129 mice, did not evoke neural responses that exceeded threshold in either strain. The strains generally did not differ in their neural responses to NaCl, quinine, and HCl. Thus, variation between the B6 and 129 strains in the peripheral gustatory system may contribute to differences in their consumption of many sweeteners. PMID:11555486

  19. Synthesis Of [2h, 13c] And [2h3, 13c]Methyl Aryl Sulfides

    DOEpatents

    Martinez, Rodolfo A.; Alvarez, Marc A.; Silks, III, Louis A.; Unkefer, Clifford J.

    2004-03-30

    The present invention is directed to labeled compounds, [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfides wherein the .sup.13 C methyl group attached to the sulfur of the sulfide includes exactly one, two or three deuterium atoms and the aryl group is selected from the group consisting of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, and R.sub.5 are each independently, hydrogen, a C.sub.1 -C.sub.4 lower alkyl, a halogen, an amino group from the group consisting of NH.sub.2, NHR and NRR' where R and R' are each a C.sub.1 -C.sub.4 lower alkyl, a phenyl, or an alkoxy group. The present invention is also directed to processes of preparing [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2,.sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfides wherein the .sup.13 C methyl group attached to the sulfur of the sulfide includes exactly one, two or three deuterium atoms. The present invention is also directed to the labeled compounds of [.sup.2 H.sub.1, .sup.13 C]methyl iodide and [.sup.2 H.sub.2, .sup.13 C]methyl iodide.

  20. Chanabayaite, Cu2(N3C2H2)Cl(NH3,Cl,H2O,□)4, a new mineral containing triazolate anion

    NASA Astrophysics Data System (ADS)

    Chukanov, N. V.; Zubkova, N. V.; Möhn, G.; Pekov, I. V.; Pushcharovsky, D. Yu.; Zadov, A. E.

    2015-12-01

    A new mineral, chanabayaite, has been discovered at a guano deposit located at Mt. Pabellón de Pica near the village of Chanabaya, Iquique Province, Tarapacá region, Chile. It is associated with salammoniac, halite, joanneumite, nitratine and earlier chalcopyrite. Chanabayaite occurs as blue translucent imperfect prismatic crystals, up to 0.05 × 0.1 × 0.5 mm in size, and their radial aggregates. Chanabayaite is brittle, with a Mohs' hardness of 2. The cleavage is perfect on (001) and imperfect on (100) and (010). D meas = 1.48(2) g/cm3, D calc = 1.464 g/cm3. The mineral is optically biaxial (-), α = 1.561(2), β = 1.615(3), γ = 1.620(2), 2 V meas = 25(10)°, 2 V calc = 33°. Pleochroism is strong, Z ≈ Y (deep blue) ≫ X (pale blue with gray tint). IR spectrum is given. The chemical composition (electron microprobe data for Cu, Fe and Cl; gas chromatography data for H, N, C and O) is as follows (wt %): 32.23 Cu, 1.14 Fe, 16.13 Cl, 3.1 H, 29.9 N, 12.2 C, 3.4 O, total is 98.1. The empirical formula is ( Z = 4): Cu1.92Fe0.08Cl1.72N8.09C3.85H11.66O0.81. The structural model was based on the single-crystal X-ray diffraction data ( R = 0.1627). Chanabayaite is orthorhombic, space group Imma, a = 19.484(3), b = 7.2136(10), c = 11.999(4) Å, V = 1686.5(7) Å3, Z = 2. In chanabayaite, chains of the corner-sharing Cu(l)-centered octahedra and single Cu(2)-centered octahedra are linked via 1,2,4-triazolate anions C2N3H2 -. NH3 and Cl- are additional ligands coordinating Cu2+. Chanabayaite is a transformational mineral species formed by leaching of Na and one third of Cl and partial dehydration of the protophase Na2Cu2Cl3(N3C2H2)2(NH3)2 • 4H2O. The strongest reflections in the powder X-ray diffraction pattern [ d, Å ( I, %) ( hkl)] are detected: 10.19 (100) (101), 6.189 (40) (011), 5.729 (23) (301), 5.216 (75) (211, 202), 4.964 (20) (400), 2.830 (20) (602, 413, 503), 2.611 (24) (123, 422, 404).

  1. C3H7NO2S effect on concrete steel-rebar corrosion in 0.5 M H2SO4 simulating industrial/microbial environment

    NASA Astrophysics Data System (ADS)

    Okeniyi, Joshua Olusegun; Nwadialo, Christopher Chukwuweike; Olu-Steven, Folusho Emmanuel; Ebinne, Samaru Smart; Coker, Taiwo Ebenezer; Okeniyi, Elizabeth Toyin; Ogbiye, Adebanji Samuel; Durotoye, Taiwo Omowunmi; Badmus, Emmanuel Omotunde Oluwasogo

    2017-02-01

    This paper investigates C3H7NO2S (Cysteine) effect on the inhibition of reinforcing steel corrosion in concrete immersed in 0.5 M H2SO4, for simulating industrial/microbial environment. Different C3H7NO2S concentrations were admixed, in duplicates, in steel-reinforced concrete samples that were partially immersed in the acidic sulphate environment. Electrochemical monitoring techniques of open circuit potential, as per ASTM C876-91 R99, and corrosion rate, by linear polarization resistance, were then employed for studying anticorrosion effect in steel-reinforced concrete samples by the organic hydrocarbon admixture. Analyses of electrochemical test-data followed ASTM G16-95 R04 prescriptions including probability distribution modeling with significant testing by Kolmogorov-Smirnov and student's t-tests statistics. Results established that all datasets of corrosion potential distributed like the Normal, the Gumbel and the Weibull distributions but that only the Weibull model described all the corrosion rate datasets in the study, as per the Kolmogorov-Smirnov test-statistics. Results of the student's t-test showed that differences of corrosion test-data between duplicated samples with the same C3H7NO2S concentrations were not statistically significant. These results indicated that 0.06878 M C3H7NO2S exhibited optimal inhibition efficiency η = 90.52±1.29% on reinforcing steel corrosion in the concrete samples immersed in 0.5 M H2SO4, simulating industrial/microbial service-environment.

  2. Measurements of I-129 in meteorites and lunar rock by tandem accelerator mass spectrometry

    NASA Technical Reports Server (NTRS)

    Nizhiizumi, K.; Arnold, J. R.; Elmore, D.; Gove, H. E.; Honda, M.

    1983-01-01

    Precise measurements of the half-life of I-129 in three different meteorites and one lunar surface rock are reported. The meteorite source of I-129 was produced by cosmic ray secondary neutron reactions on Te, while the source in lunar materials in spallation on barium and rare earth elements. The Abee, Allende, and Dhajala meteorites were examined, together with the lunar rock 14310. Details of the process used to extract the iodine are provided. The Abee and Allende samples exhibited a production of 0.5 atom/min per gm of Te from the (n,2n) reaction and 0.05 atom/min/gm for the (n,gamma) reaction. The I-129 is concluded to be a viable tool for long-lived cosmogenic nuclide studies. Further work to extend the data to include the constancy of the cosmic ray flux, the meteorite bombardment history, and the cosmic exposure age dating by means of the I-129 and Xe-129 method is indicated.

  3. Characterization Results for the 2014 HTF 3H & 2H Evaporator Overhead Samples

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

    Washington, A.

    2015-05-11

    This report tabulates the radiochemical analysis of the 3H and 2H evaporator overhead samples for 137Cs, 90Sr, and 129I to meet the requirements in the Effluent Treatment Project (ETP) Waste Acceptance Criteria (WAC) (rev. 6). This report identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. All data was found to be within the ETP WAC (rev. 6) specification for the Waste Water Collection Tanks (WWCT).

  4. Circadian and longitudinal variation of serum C-telopeptide, osteocalcin, and skeletal alkaline phosphatase in C3H/HeJ mice.

    PubMed

    Srivastava, A K; Bhattacharyya, S; Li, X; Mohan, S; Baylink, D J

    2001-10-01

    Inbred strains of mice are increasingly being used as an animal model to investigate skeletal disorders relevant to humans. In the bone field, one of the most convenient endpoints for evaluating genetic, physiological, or pharmaceutical perturbations is the use of biochemical markers. To apply biochemical markers in an effective manner, it is of key importance to establish the biological variation and appropriate sampling time. In this study, we evaluate two components: (i) circadian changes, and (ii) longitudinal variation for three serum markers, osteocalcin, C-telopeptide, and skeletal alkaline phosphatase (sALP), using 6-week-old C3H/HeJ (C3H) mice. To study circadian rhythms, the mice were randomly divided into eight groups of 15 mice each. Blood was collected at 3 h intervals, starting at 9:00 A.M. and continuing until 6:00 A.M. the next day. To determine whether circadian rhythm is intrinsically regulated or influenced by restricted food intake, it was also studied after a 12 h fasting period. Serum osteocalcin and C-telopeptide levels were measured by enzyme-linked immunoassay (ELISA) and skeletal alkaline phosphatase by a kinetic assay. The results demonstrated significant circadian variations in osteocalcin and C-telopeptide levels with a peak value between 0900 and 1200 h during daytime and a nadir between 15:00 and 18:00 h. The peak levels of C-telopeptide and osteocalcin were 26%-66% higher as compared with 24 h mean values. The pattern of the circadian variation of C-telopeptide and osteocalcin was similar in female and male animals and was not significantly affected by restricted food intake. The sALP levels were only marginally affected by the circadian rhythm. Longitudinal variations, expressed as coefficient of variation (CV), for osteocalcin, C-telopeptide, and sALP concentrations were 17%, 14%, and 16%, respectively. In addition, the longitudinal variations were not significantly influenced by the time of blood collection in sALP and osteocalcin

  5. Synergistic Heterobimetallic Manifold for Expedient Manganese(I)-Catalyzed C-H Cyanation.

    PubMed

    Liu, Weiping; Richter, Sven C; Mei, Ruhuai; Feldt, Milica; Ackermann, Lutz

    2016-12-12

    The manganese-catalyzed cyanation of inert C-H bonds was achieved within a heterobimetallic catalysis regime. The manganese(I) catalysis proved widely applicable and enabled C-H cyanations on indoles, pyrroles and thiophenes by facile C-H manganesation. The robustness of the manganese catalyst set the stage for the racemization-free C-H cyanation of amino acids with excellent levels of positional and chemo selectivity by the new cyanating agent NCFS. Experimental and computational mechanistic studies provided strong support for a synergistic heterobimetallic activation mode, facilitating the key C-C formation. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. 14 CFR 129.105 - Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Aging airplane inspections and records... § 129.105 Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft. (a... completed the aging airplane inspection and records review required by this section. During the inspection...

  7. 14 CFR 129.105 - Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Aging airplane inspections and records... § 129.105 Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft. (a... completed the aging airplane inspection and records review required by this section. During the inspection...

  8. 14 CFR 129.105 - Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Aging airplane inspections and records... § 129.105 Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft. (a... completed the aging airplane inspection and records review required by this section. During the inspection...

  9. 14 CFR 129.105 - Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aging airplane inspections and records... § 129.105 Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft. (a... completed the aging airplane inspection and records review required by this section. During the inspection...

  10. 14 CFR 129.105 - Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Aging airplane inspections and records... § 129.105 Aging airplane inspections and records reviews for U.S.-registered multiengine aircraft. (a... completed the aging airplane inspection and records review required by this section. During the inspection...

  11. Full-length genome sequences of five hepatitis C virus isolates representing subtypes 3g, 3h, 3i and 3k, and a unique genotype 3 variant.

    PubMed

    Lu, Ling; Li, Chunhua; Yuan, Jie; Lu, Teng; Okamoto, Hiroaki; Murphy, Donald G

    2013-03-01

    We characterized the full-length genomes of five distinct hepatitis C virus (HCV)-3 isolates. These represent the first complete genomes for subtypes 3g and 3h, the second such genomes for 3k and 3i, and of one novel variant presently not assigned to a subtype. Each genome was determined from 18-25 overlapping fragments. They had lengths of 9579-9660 nt and each contained a single ORF encoding 3020-3025 aa. They were isolated from five patients residing in Canada; four were of Asian origin and one was of Somali origin. Phylogenetic analysis using 64 partial NS5B sequences differentiated 10 assigned subtypes, 3a-3i and 3k, and two additional lineages within genotype 3. From the data of this study, HCV-3 full-length sequences are now available for six of the assigned subtypes and one unassigned. Our findings should add insights to HCV evolutionary studies and clinical applications.

  12. A wine tour around the world traced with 129I; potential as a forensic tool

    NASA Astrophysics Data System (ADS)

    Fitoussi, C.; Raisbeck, G. M.; Hubert, P.

    2010-04-01

    Various quantities of anthropogenic 129I have been released out worldwide in the last decades, principally by nuclear reprocessing plants in England and France. This work was a preliminary attempt to exploit the spatial and temporal variability of these emissions to investigate the possibility of tracing the provenance and age of wines worldwide. Using carrier free iodine extraction followed by measurements by Accelerator Mass Spectrometry (AMS) at the Tandetron of Gif-sur-Yvette, we find a good correlation between the distribution of 129I/ 127I and the extent to which 129I releases are expected as a function of the geographical setting. 129I concentrations, also measured in wines using the same method but with a carrier, show the same pattern.

  13. Collisions of slow polyatomic ions with surfaces: dissociation and chemical reactions of C2H2+*, C2H3+, C2H4+*, C2H5+, and their deuterated variants C2D2+* and C2D4+* on room-temperature and heated carbon surfaces.

    PubMed

    Jasík, Juraj; Zabka, Jan; Feketeova, Linda; Ipolyi, Imre; Märk, Tilmann D; Herman, Zdenek

    2005-11-17

    Interaction of C2Hn+ (n = 2-5) hydrocarbon ions and some of their isotopic variants with room-temperature and heated (600 degrees C) highly oriented pyrolytic graphite (HOPG) surfaces was investigated over the range of incident energies 11-46 eV and an incident angle of 60 degrees with respect to the surface normal. The work is an extension of our earlier research on surface interactions of CHn+ (n = 3-5) ions. Mass spectra, translational energy distributions, and angular distributions of product ions were measured. Collisions with the HOPG surface heated to 600 degrees C showed only partial or substantial dissociation of the projectile ions; translational energy distributions of the product ions peaked at about 50% of the incident energy. Interactions with the HOPG surface at room temperature showed both surface-induced dissociation of the projectiles and, in the case of radical cation projectiles C2H2+* and C2H4+*, chemical reactions with the hydrocarbons on the surface. These reactions were (i) H-atom transfer to the projectile, formation of protonated projectiles, and their subsequent fragmentation and (ii) formation of a carbon chain build-up product in reactions of the projectile ion with a terminal CH3-group of the surface hydrocarbons and subsequent fragmentation of the product ion to C3H3+. The product ions were formed in inelastic collisions in which the translational energy of the surface-excited projectile peaked at about 32% of the incident energy. Angular distributions of reaction products showed peaking at subspecular angles close to 68 degrees (heated surfaces) and 72 degrees (room-temperature surfaces). The absolute survival probability at the incident angle of 60 degrees was about 0.1% for C2H2+*, close to 1% for C2H4+* and C2H5+, and about 3-6% for C2H3+.

  14. C-H...Cl relevant discrepancy on structure, magnetic and electronic conductivity of two mixed-valence Cu{sup I}Cu{sup II} coordination polymers

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

    Shi Ling; Yang Ping; School of Chemistry and Chemical Engineering, Sun Yat-Sen University, Guangzhou 510631

    Two mixed-valence Cu{sup I}Cu{sup II} coordination polymers [Cu{sup I}Cu{sup II}(qdiol)ClL]{sub n} (qdiol{sup 2-}=2,3-dioxyquinoxalinate, L=2,2'-bipyridine, 1; L=1,10-phenanthroline, 2) were obtained in basic ethanolic solution of CuCl{sub 2}, 1,4-dihydro-2,3-quinoxalinedione and L under the solvothermal condition. 1 and 2 are similar in composition, but differ remarkably in structure. The coordination modes of Cu{sup II}, qdiol{sup 2-} and L are identical in both complexes. But the Cu{sup I} ions are two- and three-coordinated, and the Cl{sup -} ions are terminal and bridging, in 1 and 2, respectively, which are relevant to the significantly different C-H...Cl hydrogen bonding pattern of bpy and phen. The temperaturemore » variable magnetic susceptibilities show that 1 is paramagnetic and 2 is weakly antiferromagnetic. The complex impedance spectroscopic studies indicate that both 1 and 2 are semiconductors and 2 is more conducting. - Graphical Abstract: Subtly different C-H...Cl bonding nature leads to diverse coordination modes and supramolecular networks, as well as physical properties of two Cu{sup I}Cu{sup II} coordination polymers with similar compositions. Highlights: > Two new Cu(I)-Cu(II) mixed-valence coordination polymers are obtained. > Environments of Cu(I) and Cl are different caused by C-H...Cl H-bonding. > Supramolecular networks are hence diverse. > Magnetic and semiconducting properties are influenced by the structures.« less

  15. Regioselective functionalization of iminophosphoranes through Pd-mediated C-H bond activation: C-C and C-X bond formation.

    PubMed

    Aguilar, David; Navarro, Rafael; Soler, Tatiana; Urriolabeitia, Esteban P

    2010-11-21

    The orthopalladation of iminophosphoranes [R(3)P=N-C(10)H(7)-1] (R(3) = Ph(3) 1, p-Tol(3) 2, PhMe(2) 3, Ph(2)Me 4, N-C(10)H(7)-1 = 1-naphthyl) has been studied. It occurs regioselectively at the aryl ring bonded to the P atom in 1 and 2, giving endo-[Pd(μ-Cl)(C(6)H(4)-(PPh(2=N-1-C(10)H(7))-2)-κ-C,N](2) (5) or endo-[Pd(μ-Cl)(C(6)H(3)-(P(p-Tol)(2)=N-C(10)H(7)-1)-2-Me-5)-κ-C,N](2) (6), while in 3 the 1-naphthyl group is metallated instead, giving exo-[Pd(μ-Cl)(C(10)H(6)-(N=PPhMe(2))-8)-κ-C,N](2) (7). In the case of 4, orthopalladation at room temperature affords the kinetic exo isomer [Pd(μ-Cl)(C(10)H(6)-(N=PPh(2)Me)-8)-κ-C,N](2) (11exo), while a mixture of 11exo and the thermodynamic endo isomer [Pd(μ-Cl)(C(6)H(4)-(PPhMe=N-C(10)H(7)-1)-2)-κ-C,N](2) (11endo) is obtained in refluxing toluene. The heating in toluene of the acetate bridge dimer [Pd(μ-OAc)(C(10)H(6)-(N=PPh(2)Me)-8)-κ-C,N](2) (13exo) promotes the facile transformation of the exo isomer into the endo isomer [Pd(μ-OAc)(C(6)H(4)-(PPhMe=N-C(10)H(7)-1)-2)-κ-C,N](2) (13endo), confirming that the exo isomers are formed under kinetic control. Reactions of the orthometallated complexes have led to functionalized molecules. The stoichiometric reactions of the orthometallated complexes [Pd(μ-Cl)(C(10)H(6)-(N=PPhMe(2))-8)-κ-C,N](2) (7), [Pd(μ-Cl)(C(6)H(4)-(PPh(2)[=NPh)-2)](2) (17) and [Pd(μ-Cl)(C(6)H(3)-(C(O)N=PPh(3))-2-OMe-4)](2) (18) with I(2) or with CO results in the synthesis of the ortho-halogenated compounds [PhMe(2)P=N-C(10)H(6)-I-8] (19), [I-C(6)H(4)-(PPh(2)=NPh)-2] (21) and [Ph(3)P=NC(O)C(6)H(3)-I-2-OMe-5] (23) or the heterocycles [C(10)H(6)-(N=PPhMe(2))-1-(C(O))-8]Cl (20), [C(6)H(5)-(N=PPh(2)-C(6)H(4)-C(O)-2]ClO(4) (22) and [C(6)H(3)-(C(O)-1,2-N-PPh(3))-OMe-4]Cl (24).

  16. X-ray diffraction analysis of 4- and 4'-substituted C n H2 n + 1O-C6H3(OH)-CH=N-C6H4-C m H2 m + 1 ( n/ m = 2/1 and 3/4) salicylideneanilines

    NASA Astrophysics Data System (ADS)

    Kuz'mina, L. G.; Navasardyan, M. A.; Mikhailov, A. A.

    2017-11-01

    X-ray diffraction study of two crystalline modifications of C2H5O-C6H3(OH)-CH=N-C6H4-CH3 ( 1a, sp. gr. P21/ n, and 1b, sp. gr. C2/c) and C3H7O-C6H3(OH)-CH=N-C6H4-C4H9 ( 2, sp. gr. P212121) has been performed. The 1a crystal structure contains two independent molecules. The molecules are conformationally nonrigid with respect to the mutual rotation of benzene rings; the dihedral angles between their planes are 29.19° and 26.00° in the independent molecules of 1a, 18.72° in the molecule of 1b, and 50.35° in the molecule of 2. The crystal packing of the compounds is discussed.

  17. 129I and its species in the East China Sea: level, distribution, sources and tracing water masses exchange and movement

    PubMed Central

    Liu, Dan; Hou, Xiaolin; Du, Jinzhou; Zhang, Luyuan; Zhou, Weijian

    2016-01-01

    Anthropogenic 129I as a long-lived radioisotope of iodine has been considered as an ideal oceanographic tracer due to its high residence time and conservative property in the ocean. Surface water samples collected from the East China Sea (ECS) in August 2013 were analyzed for 129I, 127I and their inorganic chemical species in the first time. The measured 129I/127I ratio is 1–3 orders of magnitude higher than the pre-nuclear level, indicating its dominantly anthropogenic sources. Relatively high 129I levels were observed in the Yangtze River and its estuary, as well as in the southern Yellow Sea, and 129I level in seawater declines towards the ECS shelf. In the open sea, 129I and 127I in surface water exists mainly as iodate, while in Yangtze River estuary and some locations, iodide is dominated. The results indicate that the Fukushima nuclear accident has no detectable effects in the ECS until August 2013. The obtained results are used for investigation of interaction of various water masses and water circulation in the ECS, as well as the marine environment in this region. Meanwhile this work provides essential data for evaluation of the possible influence of the increasing NPPs along the coast of the ECS in the future. PMID:27849026

  18. Distribution and biomarkers of carbon-14-labeled fullerene C60 ([(14) C(U)]C60 ) in female rats and mice for up to 30 days after intravenous exposure.

    PubMed

    Sumner, Susan C J; Snyder, Rodney W; Wingard, Christopher; Mortensen, Ninell P; Holland, Nathan A; Shannahan, Jonathan H; Dhungana, Suraj; Pathmasiri, Wimal; Han, Li; Lewin, Anita H; Fennell, Timothy R

    2015-12-01

    A comprehensive distribution study was conducted in female rats and mice exposed to a suspension of uniformly carbon-14-labeled C60 ([(14) C(U)]C60 ). Rodents were administered [(14) C(U)]C60 (~0.9 mg kg(-1) body weight) or 5% polyvinylpyrrolidone-saline vehicle alone via a single tail vein injection. Tissues were collected at 1 h and 1, 7, 14 and 30 days after administration. A separate group of rodents received five daily injections of suspensions of either [(14) C(U)]C60 or vehicle with tissue collection 14 days post exposure. Radioactivity was detected in over 20 tissues at all time points. The highest concentration of radioactivity in rodents at each time point was in liver, lungs and spleen. Elimination of [(14) C(U)]C60 was < 2% in urine and feces at any 24 h time points. [(14) C(U)]C60 and [(14) C(U)]C60 -retinol were detected in liver of rats and together accounted for ~99% and ~56% of the total recovered at 1 and 30 days postexposure, respectively. The blood radioactivity at 1 h after [(14) C(U)]C60 exposure was fourfold higher in rats than in mice; blood radioactivity was still in circulation at 30 days post [(14) C(U)]C60 exposure in both species (<1%). Levels of oxidative stress markers increased by 5 days after exposure and remained elevated, while levels of inflammation markers initially increased and then returned to control values. The level of cardiovascular marker von Willebrand factor, increased in rats, but remained at control levels in mice. This study demonstrates that [(14) C(U)]C60 is retained in female rodents with little elimination by 30 days after i.v. exposure, and leads to systemic oxidative stress. Copyright © 2015 John Wiley & Sons, Ltd.

  19. Effects of the η(5)-C5H4(i)Pr Ligand on the Properties Exhibited by Its Tungsten Nitrosyl Complexes.

    PubMed

    Fabulyak, Diana; Baillie, Rhett A; Patrick, Brian O; Legzdins, Peter; Rosenfeld, Devon C

    2016-02-15

    Reaction of Na[η(5)-C5H4(i)Pr] with W(CO)6 in refluxing THF for 4 days generates a solution of Na[(η(5)-C5H4(i)Pr)W(CO)3] that when treated with N-methyl-N-nitroso-p-toluenesulfonamide at ambient temperatures affords (η(5)-C5H4(i)Pr)W(NO)(CO)2 (1) that is isolable in good yield as an analytically pure orange oil. Treatment of 1 with an equimolar amount of I2 in Et2O at ambient temperatures affords (η(5)-C5H4(i)Pr)W(NO)I2 (2) as a dark brown solid in excellent yield. Sequential treatment at low temperatures of 2 with 0.5 equiv of Mg(CH2CMe3)2 and Mg(CH2CH═CMe2)2 in Et2O produces the alkyl allyl complex, (η(5)-C5H4(i)Pr)W(NO)(CH2CMe3)(η(3)-CH2CHCMe2) (3), as a thermally sensitive yellow liquid. Complex 3 may also be synthesized, albeit in low yield, in one vessel at low temperatures by reacting 1 first with 1 equiv of PCl5 and then with the binary magnesium reagents specified above. Interestingly, similar treatment of 1 in Et2O with PCl5 and only 0.5 equiv of Mg(CH2CH═CMe2)2 results in the formation of the unusual complex (η(5)-C5H4(i)Pr)W(NO)(PCl2CMe2CH═CH2)Cl2 (4), which probably is formed via a metathesis reaction of the binary magnesium reagent with (η(5)-C5H4(i)Pr)W(NO)(PCl3)Cl2. The C-D activation of C6D6 by complex 3 has been investigated and compared to that exhibited by its η(5)-C5Me5, η(5)-C5Me4H, and η(5)-C5Me4(n)Pr analogues. Kinetic analyses of the various activations have established that the presence of the η(5)-C5H4(i)Pr ligand significantly increases the rate of the reaction, an outcome that can be attributed to a combination of steric and electronic factors. In addition, mechanistic studies have established that in solution 3 loses neopentane under ambient conditions to generate exclusively the 16e η(2)-diene intermediate complex (η(5)-C5H4(i)Pr)W(NO)(η(2)-CH2═CMeCH═CH2), which then effects the subsequent C-D activations. This behavior contrasts with that exhibited by the η(5)-C5Me5 analogue of 3 which forms both η(2

  20. Synthesis of a Benzodiazepine-derived Rhodium NHC Complex by C-H Bond Activation

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

    Bergman, Roberg G.; Gribble, Jr., Michael W.; Ellman, Jonathan A.

    2008-01-30

    The synthesis and characterization of a Rh(I)-NHC complex generated by C-H activation of 1,4-benzodiazepine heterocycle are reported. This complex constitutes a rare example of a carbene tautomer of a 1,4-benzodiazepine aldimine stabilized by transition metal coordination and demonstrates the ability of the catalytically relevant RhCl(PCy{sub 3}){sub 2} fragment to induce NHC-forming tautomerization of heterocycles possessing a single carbene-stabilizing heteroatom. Implications for the synthesis of benzodiazepines and related pharmacophores via C-H functionalization are discussed.

  1. Sol-gel synthesis of K{sub 3}InF{sub 6} and structural characterization of K{sub 2}InC{sub 10}O{sub 10}H{sub 6}F{sub 9}, K{sub 3}InC{sub 12}O{sub 14}H{sub 4}F{sub 18} and K{sub 3}InC{sub 12}O{sub 12}F{sub 18}

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

    Labeguerie, Jessica; Gredin, Patrick; Marrot, Jerome

    2005-10-15

    K{sub 3}InF{sub 6} is synthesized by a sol-gel route starting from indium and potassium acetates dissolved in isopropanol in the stoichiometry 1:3, with trifluoroacetic acid as fluorinating agent. The crystal structures of the organic precursors were solved by X-ray diffraction methods on single crystals. Three organic compounds were isolated and identified: K{sub 2}InC{sub 10}O{sub 10}H{sub 6}F{sub 9}, K{sub 3}InC{sub 12}O{sub 14}H{sub 4}F{sub 18} and K{sub 3}InC{sub 12}O{sub 12}F{sub 18}. The first one, deficient in potassium in comparison with the initial stoichiometry, is unstable. In its crystal structure, acetate as well as trifluoroacetate anions are coordinated to the indium atom. Themore » two other precursors are obtained, respectively, by quick and slow evaporation of the solution. They correspond to the final organic compounds, which give K{sub 3}InF{sub 6} by decomposition at high temperature. The crystal structure of K{sub 3}InC{sub 12}O{sub 14}H{sub 4}F{sub 18} is characterized by complex anions [In(CF{sub 3}COO){sub 4}(OH{sub x}){sub 2}]{sup (5-2x)-} and isolated [CF{sub 3}COOH{sub 2-x}]{sup (x-1)-} molecules with x=2 or 1, surrounded by K{sup +} cations. The crystal structure of K{sub 3}InC{sub 12}O{sub 12}F{sub 18} is only constituted by complex anions [In(CF{sub 3}COO){sub 6}]{sup 3-} and K{sup +} cations. For all these compounds, potassium cations ensure only the electroneutrality of the structure. IR spectra of K{sub 2}InC{sub 10}O{sub 10}H{sub 6}F{sub 9} and K{sub 3}InC{sub 12}O{sub 12}F{sub 18} were also performed at room temperature on pulverized crystals.« less

  2. Dipole moments and transition probabilities of the i 3Pi sub g-b 3Sigma(+) sub u, c 3Pi sub u-a 3Sigma(+) sub g, and i 3Pi sub g-c 3Pi sub u systems of molecular hydrogen

    NASA Technical Reports Server (NTRS)

    Guberman, Steven L.; Dalgarno, A.

    1992-01-01

    Bonn-Oppenheimer-based ab initio calculations of dipole moments from the i 3Pi sub g-b 3Sigma(+) sub u, c 3Pi sub u-a 3Sigma(+) sub g, and i 3Pi sub g-c 3Pi sub u transitions of H2 have been conducted, to yield a tabulation of the dipole transition probabilities and Franck-Condon factors. These factors are given for transitions originating in the lowest vibrational level of the ground X 1Sigma(+) sub g state.

  3. Thermoelectric power study of Ag 7C 6H 14NI 8 material

    NASA Astrophysics Data System (ADS)

    Khalifa, M. M.; EL-Mashri, S. M.; Avasthi, M. N.

    2002-08-01

    Thermoelectric power of the material Ag 7C 6H 14NI 8 has been studied for the first time in the temperature range 20-l00°C. Thermopower versus 1/ T plot comes out to be a straight line and can be represented by the equation -θ=0.15 {10 3}/{T}+0.06 for the material. Heat of transport of Ag + ion in the material is very nearly equal to the activation energy. The work points towards the correctness of the Rice and Roth model. It also shows that the material is ordered.

  4. An Expanding H I Photodissociated Region Associated with the Compact H II Region G213.880-11.837 in the GGD 14 Complex

    NASA Astrophysics Data System (ADS)

    Gómez, Y.; Garay, G.; Rodríguez-Rico, C. A.; Neria, C.; Rodríguez, L. F.; Escalante, V.; Lizano, S.; Lebrón, M.

    2010-10-01

    We present high angular and spectral resolution H I 21 cm line observations toward the cometary-shaped compact H II region G213.880-11.837 in the GGD 14 complex. The kinematics and morphology of the photodissociated region, traced by the H I line emission, reveal that the neutral gas is part of an expanding flow. The kinematics of the H I gas along the major axis of G213.880-11.837 shows that the emission is very extended toward the SE direction, reaching local standard of rest (LSR) radial velocities in the tail of about 14 km s-1. The ambient LSR radial velocity of the molecular gas is 11.5 km s-1, which suggests a champagne flow of the H I gas. This is the second (after G111.61+0.37) cometary H II/H I region known.

  5. Structure of 14C and 14B from the C,1514(d ,3He)B,1413 reactions

    NASA Astrophysics Data System (ADS)

    Bedoor, S.; Wuosmaa, A. H.; Albers, M.; Alcorta, M.; Almaraz-Calderon, Sergio; Back, B. B.; Bertone, P. F.; Deibel, C. M.; Hoffman, C. R.; Lighthall, J. C.; Marley, S. T.; Mcneel, D. G.; Pardo, R. C.; Rehm, K. E.; Schiffer, J. P.; Shetty, D. V.

    2016-04-01

    We have studied the C,1514(d ,3He)B,1413 proton-removing reactions in inverse kinematics. The (d ,3He ) reaction probes the proton occupation of the target ground state, and also provides spectroscopic information about the final states in B,1413. The experiments were performed using C,1514 beams from the ATLAS accelerator at Argonne National Laboratory. The reaction products were analyzed with the HELIOS device. Angular distributions were obtained for transitions from both reactions. The 14C-beam data reveal transitions to excited states in 13B that suggest configurations with protons outside the π (0 p3 /2) orbital, and some possibility of proton cross-shell 0 p -1 s 0 d excitations, in the 14C ground state. The 15C-beam data confirm the existence of a broad 2- excited state in 14B. The experimental data are compared to the results of shell-model calculations.

  6. [C6 H14 N]PbBr3 : An ABX3 -Type Semiconducting Perovskite Hybrid with Above-Room-Temperature Phase Transition.

    PubMed

    Zhang, Jing; Liu, Xitao; Li, Xianfeng; Han, Shiguo; Tao, Kewen; Wang, Yuyin; Ji, Chengmin; Sun, Zhihua; Luo, Junhua

    2018-04-16

    Organic-inorganic hybrid perovskites, with the formula ABX 3 (A=organic cation, B=metal cation, and X=halide; for example, CH 3 NH 3 PbI 3 ), have diverse and intriguing physical properties, such as semiconduction, phase transitions, and optical properties. Herein, a new ABX 3 -type semiconducting perovskite-like hybrid, (hexamethyleneimine)PbBr 3 (1), consisting of one-dimensional inorganic frameworks and cyclic organic cations, is reported. Notably, the inorganic moiety of 1 adopts a perovskite-like architecture and forms infinite columns composed of face-sharing PbBr 6 octahedra. Strikingly, the organic cation exhibits a highly flexible molecular configuration, which triggers an above-room-temperature phase transition, at T c =338.8 K; this is confirmed by differential scanning calorimetry (DSC), specific heat capacity (C p ), and dielectric measurements. Further structural analysis reveals that the phase transition originates from the molecular configurational distortion of the organic cations coupled with small-angle reorientation of the PbBr 6 octahedra inside the inorganic components. Moreover, temperature-dependent conductivity and UV/Vis absorption measurements reveal that 1 also displays semiconducting behavior below T c . It is believed that this work will pave a potential way to design multifeatured perovskite hybrids by utilizing cyclic organic amines. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Observational infant exploratory [(14)C]-paracetamol pharmacokinetic microdose/therapeutic dose study with accelerator mass spectrometry bioanalysis.

    PubMed

    Garner, Colin R; Park, Kevin B; French, Neil S; Earnshaw, Caroline; Schipani, Alessandro; Selby, Andrew M; Byrne, Lindsay; Siner, Sarah; Crawley, Francis P; Vaes, Wouter H J; van Duijn, Esther; deLigt, Rianne; Varendi, Heili; Lass, Jane; Grynkiewicz, Grzegorz; Maruszak, Wioletta; Turner, Mark A

    2015-07-01

    The aims of the study were to compare [(14)C]-paracetamol ([(14)C]-PARA) paediatric pharmacokinetics (PK) after administration mixed in a therapeutic dose or an isolated microdose and to develop further and validate accelerator mass spectrometry (AMS) bioanalysis in the 0-2 year old age group. [(14)C]-PARA concentrations in 10-15 µl plasma samples were measured after enteral or i.v. administration of a single [(14)C]-PARA microdose or mixed in with therapeutic dose in infants receiving PARA as part of their therapeutic regimen. Thirty-four infants were included in the PARA PK analysis for this study: oral microdose (n = 4), i.v. microdose (n = 6), oral therapeutic (n = 6) and i.v. therapeutic (n = 18). The respective mean clearance (CL) values (SDs in parentheses) for these dosed groups were 1.46 (1.00) l h(-1), 1.76 (1.07) l h(-1), 2.93 (2.08) l h(-1) and 2.72 (3.10) l h(-1), t(1/2) values 2.65 h, 2.55 h, 8.36 h and 7.16 h and dose normalized AUC(0-t) (mg l(-1) h) values were 0.90 (0.43), 0.84 (0.57), 0.7 (0.79) and 0.54 (0.26). All necessary ethical, scientific, clinical and regulatory procedures were put in place to conduct PK studies using enteral and systemic microdosing in two European centres. The pharmacokinetics of a therapeutic dose (mg kg(-1)) and a microdose (ng kg(-1)) in babies between 35 to 127 weeks post-menstrual age. [(14)C]-PARA pharmacokinetic parameters were within a two-fold range after a therapeutic dose or a microdose. Exploratory studies using doses significantly less than therapeutic doses may offer ethical and safety advantages with increased bionalytical sensitivity in selected exploratory paediatric pharmacokinetic studies. © 2015 The British Pharmacological Society.

  8. 14 CFR 129.17 - Aircraft communication and navigation equipment for operations under IFR or over the top.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft communication and navigation....S.-REGISTERED AIRCRAFT ENGAGED IN COMMON CARRIAGE General § 129.17 Aircraft communication and... accuracy required for ATC; (ii) One marker beacon receiver providing visual and aural signals; and (iii...

  9. Electrical conductivity, differential scanning calorimetry, X-ray diffraction, and 7Li nuclear magnetic resonance studies of n-C x H(2 x+1)OSO3Li ( x = 12, 14, 16, 18, and 20)

    NASA Astrophysics Data System (ADS)

    Hirakawa, Satoru; Morimoto, Yoshiaki; Honda, Hisashi

    2015-04-01

    Electrical conductivity ( σ), differential scanning calorimetry (DSC), and X-ray diffraction (XRD) measurements of n-C x H (2 x+1) OSO 3Li ( x= 12, 14, 16, 18, and 20) crystals were performed as a function of temperature. In addition, σ, DSC, and XRD observations of n-C x H (2 x+1) OSO 3Na and n-C x H (2 x+1) OSO 3K ( x= 12, 14, 16, 18, and 20) crystals were carried out for comparison. DSC results of the salts revealed several solid-solid phase transitions with large entropy changes (Δ S). For n-C 18 H 37 OSO 3Li and n-C 20 H 41 OSO 3Li salts, each melting point produced a small Δ S mp value compared with the total entropy change in the solid phases (Δ S tr1+Δ S tr2). Additionally, Li + ion diffusion was detected in the highest temperature solid phases. For K salts, larger σ values were detected for potassium alkylsulfates compared with those reported for alkyl carboxylate. 7Li NMR spectra of n-C 18 H 37 OSO 3Li crystals recorded in the low-temperature phase showed large asymmetry parameters, suggesting the Li + ions are localized at asymmetric sites in the crystals.

  10. 14 CFR 382.129 - What other requirements apply when passengers' wheelchairs, other mobility aids, and other...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 4 2010-01-01 2010-01-01 false What other requirements apply when...? 382.129 Section 382.129 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS NONDISCRIMINATION ON THE BASIS OF DISABILITY IN AIR TRAVEL...

  11. 14 CFR 382.129 - What other requirements apply when passengers' wheelchairs, other mobility aids, and other...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 4 2011-01-01 2011-01-01 false What other requirements apply when...? 382.129 Section 382.129 Aeronautics and Space OFFICE OF THE SECRETARY, DEPARTMENT OF TRANSPORTATION (AVIATION PROCEEDINGS) SPECIAL REGULATIONS NONDISCRIMINATION ON THE BASIS OF DISABILITY IN AIR TRAVEL...

  12. Copper Causes Regiospecific Formation of C4F8-Containing Six-Membered Rings and their Defluorination/Aromatization to C4F4-Containing Rings in Triphenylene/1,4-C4F8I2 Reactions

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

    Rippy, Kerry C.; Bukovsky, Eric V.; Clikeman, Tyler T.

    The presence of Cu in reactions of triphenylene (TRPH) and 1,4-C4F8I2 at 360 °C led to regiospecific substitution of TRPH ortho C(β) atoms to form C4F8-containing rings, completely suppressing substitution on C(α) atoms. In addition, Cu caused selective reductive-defluorination/aromatization (RD/A) to form C4F4- containing aromatic rings. Without Cu, the reactions of TRPH and 1,4- C4F8I2 were not regiospecific and no RD/A was observed. These results, supported by DFT calculations, are the first examples of Cupromoted (i) regiospecific perfluoroannulation, (ii) preparative C–F activation, and (iii) RD/A. HPLC-purified products were characterized by X-ray diffraction, low-temperature PES, and 1H/19F NMR.

  13. Molecular environment of stable iodine and radioiodine (129I) in natural organic matter: Evidence inferred from NMR and binding experiments at environmentally relevant concentrations

    NASA Astrophysics Data System (ADS)

    Xu, Chen; Zhong, Junyan; Hatcher, Patrick G.; Zhang, Saijin; Li, Hsiu-Ping; Ho, Yi-Fang; Schwehr, Kathleen A.; Kaplan, Daniel I.; Roberts, Kimberly A.; Brinkmeyer, Robin; Yeager, Chris M.; Santschi, Peter H.

    2012-11-01

    129I is a major by-product of nuclear fission and had become one of the major radiation risk drivers at Department of Energy (DOE) sites. 129I is present at elevated levels in the surface soils of the Savannah River Site (SRS) F-Area and was found to be bound predominantly to soil organic matter (SOM). Naturally bound 127I and 129I to sequentially extracted humic acids (HAs), fulvic acids (FAs) and a water extractable colloid (WEC) were measured in a 129I-contaminated wetland surface soil located on the SRS. WEC is a predominantly colloidal organic fraction obtained from soil re-suspension experiments to mimic the fraction that may be released during groundwater exfiltration, storm water or surface runoff events. For the first time, NMR techniques were applied to infer the molecular environment of naturally occurring stable iodine and radioiodine binding to SOM. Iodine uptake partitioning coefficients (Kd) by these SOM samples at ambient iodine concentrations were also measured and related to quantitative structural analyses by 13C DPMAS NMR and solution state 1H NMR on the eight humic acid fractions. By assessing the molecular environment of iodine, it was found that it was closely associated with the aromatic regions containing esterified products of phenolic and formic acids or other aliphatic carboxylic acids, amide functionalities, quinone-like structures activated by electron-donating groups (e.g., NH2), or a hemicellulose-lignin-like complex with phenyl-glycosidic linkages. However, FAs and WEC contained much greater concentrations of 127I or 129I than HAs. The contrasting radioiodine contents among the three different types of SOM (HAs, FAs and WEC) suggest that the iodine binding environment cannot be explained solely by the difference in the amount of their reactive binding sites. Instead, indirect evidence indicates that the macro-molecular conformation, such as the hydrophobic aliphatic periphery hindering the active aromatic cores and the hydrophilic

  14. Syntheses, structures, and vibrational spectroscopy of the two-dimensional iodates Ln(IO{sub 3}){sub 3} and Ln(IO{sub 3}){sub 3}(H{sub 2}O) (Ln =Yb, Lu)

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

    Assefa, Zerihun; Ling Jie; Haire, Richard G.

    2006-12-15

    The reaction of Lu{sup 3+} or Yb{sup 3+} and H{sub 5}IO{sub 6} in aqueous media at 180 {sup o}C leads to the formation of Yb(IO{sub 3}){sub 3}(H{sub 2}O) or Lu(IO{sub 3}){sub 3}(H{sub 2}O), respectively, while the reaction of Yb metal with H{sub 5}IO{sub 6} under similar reaction conditions gives rise to the anhydrous iodate, Yb(IO{sub 3}){sub 3}. Under supercritical conditions Lu{sup 3+} reacts with HIO{sub 3} and KIO{sub 4} to yield the isostructural Lu(IO{sub 3}){sub 3}. The structures have been determined by single-crystal X-ray diffraction. Crystallographic data are (MoK{alpha}, {lambda}=0.71073 A): Yb(IO{sub 3}){sub 3}, monoclinic, space group P2{sub 1}/n, a=8.6664(9)more » A, b=5.9904(6) A, c=14.8826(15) A, {beta}=96.931(2){sup o}, V=766.99(13), Z=4, R(F)=4.23% for 114 parameters with 1880 reflections with I>2{sigma}(I); Lu(IO{sub 3}){sub 3}, monoclinic, space group P2{sub 1}/n, a=8.6410(9), b=5.9961(6), c=14.8782(16) A, {beta}=97.028(2){sup o}, V=765.08(14), Z=4, R(F)=2.65% for 119 parameters with 1756 reflections with I>2{sigma}(I); Yb(IO{sub 3}){sub 3}(H{sub 2}O), monoclinic, space group C2/c, a=27.2476(15), b=5.6296(3), c=12.0157(7) A, {beta}=98.636(1){sup o}, V=1822.2(2), Z=8, R(F)=1.51% for 128 parameters with 2250 reflections with I>2{sigma}(I); Lu(IO{sub 3}){sub 3}(H{sub 2}O), monoclinic, space group C2/c, a=27.258(4), b=5.6251(7), c=12.0006(16) A, {beta}=98.704(2){sup o}, V=1818.8(4), Z=8, R(F)=1.98% for 128 parameters with 2242 reflections with I>2{sigma}(I). The f elements in all of the compounds are found in seven-coordinate environments and bridged with monodentate, bidentate, or tridentate iodate anions. Both Lu(IO{sub 3}){sub 3}(H and Yb(IO{sub 3}){sub 3}(H{sub 2}O) display distinctively different vibrational profiles from their respective anhydrous analogs. Hence, the Raman profile can be used as a complementary diagnostic tool to discern the different structural motifs of the compounds. - Graphical abstract: Four new metal iodates, Yb

  15. Down-regulation of p-coumaroyl quinate/shikimate 3'-hydroxylase (C3'H) and cinnamate 4-hydroxylase (C4H) genes in the lignin biosynthetic pathway of Eucalyptus urophylla x E. grandis leads to improved sugar release

    DOE PAGES

    Sykes, Robert W.; Gjersing, Erica L.; Foutz, Kirk; ...

    2015-08-27

    In this study, lignocellulosic materials provide an attractive replacement for food-based crops used to produce ethanol. Understanding the interactions within the cell wall is vital to overcome the highly recalcitrant nature of biomass. One factor imparting plant cell wall recalcitrance is lignin, which can be manipulated by making changes in the lignin biosynthetic pathway. In this study, eucalyptus down-regulated in expression of cinnamate 4-hydroxylase (C4H, EC 1.14.13.11) or p-coumaroyl quinate/shikimate 3'-hydroxylase (C3'H, EC 1.14.13.36) were evaluated for cell wall composition and reduced recalcitrance.

  16. C2-Selective Branched Alkylation of Benzimidazoles by Rhodium(I)-Catalyzed C-H Activation.

    PubMed

    Tran, Gaël; Confair, Danielle; Hesp, Kevin D; Mascitti, Vincent; Ellman, Jonathan A

    2017-09-01

    Herein, we report a Rh(I)/bisphosphine/K 3 PO 4 catalytic system allowing for the first time the selective branched C-H alkylation of benzimidazoles with Michael acceptors. Branched alkylation with N,N-dimethyl acrylamide was successfully applied to the alkylation of a broad range of benzimidazoles incorporating a variety of N-substituents and with both electron-rich and -poor functionality displayed at different sites of the arene. Moreover, the introduction of a quaternary carbon was achieved by alkylation with ethyl methacrylate. The method was also shown to be applicable to the C2-selective branched alkylation of azabenzimidazoles.

  17. About 129Xe ∗ in meteoritic nanodiamonds

    NASA Astrophysics Data System (ADS)

    Fisenko, A. V.; Semjonova, L. F.

    2008-08-01

    The analysis of excess 129Xe in meteoritic nanodiamonds and the kinetics of its release during stepwise pyrolysis allow to suggest that (1) in the solar nebula 129I atoms were adsorbed onto nanodiamond grains and (or) chemisorbed by forming covalent bonds with carbon atoms. Most 129I atoms existed in a surface connected state, but a minor amount of them was in nanopores of the grains. At radioactive decay of 129I the formed 129Xe ( 129Xe ∗) was trapped by diamond grains due to nuclear recoil. (2) During thermal metamorphism or aqueous alteration, the surface-sited 129I atoms were basically lost. On the basis of these assumptions and calculated concentrations of 129Xe ∗ in meteoritic nanodiamonds it is shown that the minimum closing time of the I-Xe system for meteorites of different chemical classes and low petrologic types may be about one million years relative to the minimally thermally metamorphized CO3 meteorite ALHA 77307. With increasing metamorphic grade the closing time of the I-Xe system increases and can range up to several ten millions years. This tendency is in agreement with an onion-shell model of structure and cooling history of meteorite parent bodies where the temperature increases in the direction from surface to center of the asteroids.

  18. Ilyukhinite (H3O,Na)14Ca6Mn2Zr3Si26O72(OH)2 • 3H2O, a New Mineral of the Eudialyte Group

    NASA Astrophysics Data System (ADS)

    Chukanov, N. V.; Rastsvetaeva, R. K.; Rozenberg, K. A.; Aksenov, S. M.; Pekov, I. V.; Belakovsky, D. I.; Kristiansen, R.; Van, K. V.

    2017-12-01

    A new eudialyte-group mineral, ilyukhinite, ideally (H3O,Na)14Ca6Mn2Zr3Si26O72(OH)2 · 3H2O, has been found in peralkaline pegmatite at Mt. Kukisvumchorr, Khibiny alkaline pluton, Kola Peninsula, Russia. It occurs as brownish orange, with vitreous luster anhedral grains up to 1 mm across in hydrothermally altered peralkaline rock, in association with aegirine, murmanite, albite, microcline, rhabdophane-(Ce), fluorite, sphalerite and molybdenite. The Mohs hardness is 5; cleavage is not observed. D meas 2.67(2), D calc 2.703 g/cm3. Ilyukhinite is optically uniaxial (-): ω = 1.585(2), ɛ = 1.584(2). The IR spectrum is given. The average chemical composition of ilyukhinite (wt %; electron microprobe, ranges given in parentheses; H2O determined by gas chromatography) is as follows: 3.07 (3.63-4.43) Na2O, 0.32 (0.28-0.52) K2O, 10.63 (10.26-10.90) CaO, 3.06 (2.74-3.22) MnO, 1.15 (0.93-1.37) FeO, 0.79 (0.51-0.89) La2O3, 1.21 (0.97-1.44) Ce2O3, 0.41 (0.30-0.56) Nd2O3, 0.90 (0.77-1.12) TiO2, 10.94 (10.15-11.21) ZrO2, 1.40 (0.76-1.68) Nb2O5, 51.24 (49.98-52.28) SiO2, 1.14 (0.89-1.37) SO3, 0.27 (0.19—0.38) Cl, 10.9(5 )H2O,-0.06-O = C1, total is 98.27. The empirical formula is H36.04(Na3.82K0.20)(Ca5.65Ce0.22La0.14Nd0.07)(Mn1.285Fe0.48)(Zr2.645Ti0.34)Nb0.31Si25.41S0.42Cl0.23O86.82. The crystal structure has been solved ( R = 0.046). Ilyukhinite is trigonal, R3 m; a = 14.1695(6) Å, b = 31.026(1) Å, V = 5394.7(7) Å3, Z = 3. The strongest XRD reflections [ d, Å (I, %) ( hkl)] are 11.44 (82) (101), 7.09 (70) (110), 6.02 (44) (021), 4.371 (89) 205), 3.805 (47) (303, 033), 3.376 (41) (131), 2.985 (100) (315, 128), 2.852 (92) (404). Ilyukhinite was named in memory of Vladimir V. Ilyukhin (1934-1982), an outstanding Soviet crystallographer. The type specimen of ilyukhinite has been deposited in the collection of the Natural History Museum, University of Oslo, Norway.

  19. Synthetic, Infrared, 1H and 13C NMR Spectral Studies on N-(2-/3-Substituted Phenyl)-4-Substituted Benzenesulphonamides, 4-X'C6H4SO2NH(2-/3-XC6H4), where X' = H, CH3, C2H5, F, Cl or Br, and X = CH3 or Cl

    NASA Astrophysics Data System (ADS)

    Gowda, B. Thimme; Shetty, Mahesha; Jayalakshmi, K. L.

    2005-02-01

    Twenty three N-(2-/3-substituted phenyl)-4-substituted benzenesulphonamides of the general formula, 4-X'C6H4SO2NH(2-/3-XC6H4), where X' = H, CH3, C2H5, F, Cl or Br and X = CH3 or Cl have been prepared and characterized, and their infrared spectra in the solid state, 1H and 13C NMR spectra in solution were studied. The N-H stretching vibrations, νN-H, absorb in the range 3285 - 3199 cm-1, while the asymmetric and symmetric SO2 vibrations vary in the ranges 1376 - 1309 cm-1 and 1177 - 1148 cm-1, respectively. The S-N and C-N stretching vibrations absorb in the ranges 945 - 893 cm-1 and 1304 - 1168 cm-1, respectively. The compounds do not exhibit particular trends in the variation of these frequencies on substitution either at ortho or meta positions with either a methyl group or Cl. The observed 1H and 13C chemical shifts of are assigned to protons and carbons of the two benzene rings. Incremental shifts of the ring protons and carbons due to -SO2NH(2-/3-XC6H4) groups in C6H5SO2NH(2-/3-XC6H4), and 4- X'C6H4SO2- and 4-X'C6H4SO2NH- groups in 4-X'C6H4SO2NH(C6H5) are computed and employed to calculate the chemical shifts of the ring protons and carbons in the substituted compounds, 4-X'C6H4SO2NH(2-/3-XC6H4). The computed values agree well with the observed chemical shifts.

  20. Investigations of 3C-SiC inclusions in 4H-SiC epilayers on 4H-SiC single crystal substrates

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

    Si, W.; Dudley, M.; Kong, H.S.

    1997-03-01

    Synchrotron white beam x-ray topography (SWBXT) and Nomarski optical microscopy (NOM) have been used to characterize 4H-SiC epilayers and to study the character of triangular inclusions therein. 4H-SiC substrates misoriented by a range of angles from (0001), as well as (1 1{bar 0}0) and (11 2{bar 0}) oriented substrates were used. No evidence was found for the nucleation of 3C-SiC inclusions at superscrew dislocations (along the [0001] axis) in the 4H-SiC substrates. Increasing the off-axis angle of the substrates from 3.5 to 6.5{degree} was found to greatly suppress the formation of the triangular inclusions. In the case of substrates misorientedmore » by 8.0{degree} from (0001) toward [112{bar 0}], the triangular inclusions were virtually eliminated. The crystalline quality of 4H-SiC epilayers grown on the substrates misoriented by 8.0{degree} from (0001) was very good. For the (11{bar 0}0) and (112{bar 0}) samples, there is no indication of 3C-SiC inclusions in the epilayers. Possible formation mechanisms and the morphology of 3C-SiC inclusions are discussed. 17 refs., 13 figs.« less

  1. Formation of a 1,4-diamino-2,3-disila-1,3-butadiene derivative.

    PubMed

    Mondal, Kartik Chandra; Roesky, Herbert W; Dittrich, Birger; Holzmann, Nicole; Hermann, Markus; Frenking, Gernot; Meents, Alke

    2013-10-30

    A 1,4-diamino-2,3-disila-1,3-butadiene derivative of composition (Me2-cAAC)2(Si2Cl2) (Me2-cAAC = :C(CMe2)2(CH2)N-2,6-iPr2C6H3) was synthesized by reduction of the Me2-cAAC:SiCl4 adduct with KC8. This compound is stable at 0 °C for 3 months in an inert atmosphere. Theoretical studies reveal that the silicon atoms exhibit pyramidal coordination, where the Cl-Si-Si-Cl dihedral angle is twisted by 43.3° (calcd 45.9°). The two silicon-carbon bonds are intermediates between single and double Si-C bonds due to twisting of the C-Si-Si-C dihedral angle (163.6°).

  2. Synthesis and structure of the extended phosphazane ligand [(1,4-C6H4){N(μ-PN(t)Bu)2N(t)Bu}2](4).

    PubMed

    Sevilla, Raquel; Less, Robert J; García-Rodríguez, Raúl; Bond, Andrew D; Wright, Dominic S

    2016-02-07

    The reaction of the phenylene-bridged precursor (1,4-C6H4)[N(PCl2)2]2 with (t)BuNH2 in the presence of Et3N gives the new ligand precursor (1,4-C6H4)[N(μ-N(t)Bu)2(PNH(t)Bu)2]2, deprotonation of which with Bu2Mg gives the novel tetraanion [(1,4-C6H4){N(μ-N(t)Bu)2(PN(t)Bu)2}2](4-).

  3. Growth of Defect-Free 3C-SiC on 4H- and 6H-SiC Mesas Using Step-Free Surface Heteroepitaxy

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Powell, J. Anthony; Trunek, Andrew J.; Huang, Xianrong R.; Dudley, Michael

    2001-01-01

    A new growth process, herein named step-free surface heteroepitaxy, has achieved 3CSiC films completely free of double positioning boundaries and stacking faults on 4H-SiC and 6H-SiC substrate mesas. The process is based upon the initial 2-dimensional nucleation and lateral expansion of a single island of 3C-SiC on a 4H- or 6H-SiC mesa surface that is completely free of bilayer surface steps. Our experimental results indicate that substrate-epilayer in-plane lattice mismatch (delta a/a = 0.0854% for 3C/4H) is at least partially relieved parallel to the interface in the initial bilayers of the heterofilm, producing an at least partially relaxed 3C-SiC film without dislocations that undesirably thread through the thickness of the epilayer. This result should enable realization of improved 3C-SiC devices.

  4. Effects of radiochemical impurities on measurements of transfer constants for [14C]sucrose permeation of normal and injured blood-brain barrier of rats.

    PubMed

    Preston, E; Foster, D O; Mills, P A

    1998-01-01

    Radiolabeled sucrose is often used to assess blood-brain barrier (BBB) injury in the rat, but published transfer constants (K[i]s) for sucrose permeation of the intact BBB (control K[i]s) are highly discrepant. A potential problem with the commonly used tracer, [14C(U)]sucrose, is radiolytic generation, preuse, of radiocontaminants that might readily penetrate the BBB. How such contaminants might affect measurements of sucrose K(i)s was examined for both the intact and the ischemically injured BBB. Three stocks of [14C(U)]sucrose were studied: newly purchased ("new"), 4-year-old, and 7-year-old. A high purity (99.9%) "new" and a 2-year-old stock of [3H(fructose-1)]sucrose were also tested. Pentobarbital-anesthetized male Sprague-Dawley rats were injected i.v. with each tracer separately (six to eight rats) and K(i)s in five brain regions were measured by the multiple-time graphical method. The "new" 14C-, "new" 3H-, and 2-year-old 3H-sucrose yielded comparable K(i)s , ranging from 1.2 +/- 0.1 to 2.4 +/- 0.3 nl x g(-1) x s(-1) (mean +/- SE) across the regions. The two old stocks of 14C-sucrose yielded significantly higher regional K(i)s : 5.1-6.3 (4-year-old) and 8.4-9.7 (7-year-old). Thin-layer chromatography of the three 14C-tracers revealed that each contained radioimpurities (ca. 2% in both the "new" and 4-year-old, and 9% in the 7-year-old), but that the old stocks contained larger amounts of relatively mobile (more lipophilic) impurities, which can be suspected as the main cause of the elevated K(i)s obtained. Additional rats were subjected to 10 min of cerebral ischemia, which effects a delayed BBB injury, and 6 h later the "new" 3H- and the 4-year-old 14C-sucrose were injected together. The K(i)s for both tracers were elevated by like, absolute amounts (deltaK[i]s), but by very different percentages, over their disparate baseline values in uninjured rats (for striatum and hippocampus, the most injured regions, deltaK(i)s were 3.9 to 4.4 nl x g[-1] x s[-1

  5. The structures of 1,4-diaryl-5-trifluoromethyl-1H-1,2,3-triazoles related to J147, a drug for treating Alzheimer's disease.

    PubMed

    Farrán, M Ángeles; Bonet, M Ángels; Claramunt, Rosa M; Torralba, M Carmen; Alkorta, Ibon; Elguero, José

    2018-04-01

    J147 [N-(2,4-dimethylphenyl)-2,2,2-trifluoro-N'-(3-methoxybenzylidene)acetohydrazide] has recently been reported as a promising new drug for the treatment of Alzheimer's disease. The X-ray structures of seven new 1,4-diaryl-5-trifluoromethyl-1H-1,2,3-triazoles, namely 1-(3,4-dimethylphenyl)-4-phenyl-5-trifluoromethyl-1H-1,2,3-triazole (C 17 H 14 F 3 N 3 , 1), 1-(3,4-dimethylphenyl)-4-(3-methoxyphenyl)-5-trifluoromethyl-1H-1,2,3-triazole (C 18 H 16 F 3 N 3 O, 2), 1-(3,4-dimethylphenyl)-4-(4-methoxyphenyl)-5-trifluoromethyl-1H-1,2,3-triazole (C 18 H 16 F 3 N 3 O, 3), 1-(2,4-dimethylphenyl)-4-(4-methoxyphenyl)-5-trifluoromethyl-1H-1,2,3-triazole (C 18 H 16 F 3 N 3 O, 4), 1-[2,4-bis(trifluoromethyl)phenyl]-4-(3-methoxyphenyl)-5-trifluoromethyl-1H-1,2,3-triazole (C 18 H 10 F 9 N 3 O, 5), 1-(3,4-dimethoxyphenyl)-4-(3,4-dimethoxyphenyl)-5-trifluoromethyl-1H-1,2,3-triazole (C 19 H 18 F 3 N 3 O 4 , 6) and 3-[4-(3,4-dimethoxyphenyl)-5-(trifluoromethyl)-1H-1,2,3-triazol-1-yl]phenol (C 17 H 14 F 3 N 3 O 3 , 7), have been determined and compared to that of J147. B3LYP/6-311++G(d,p) calculations have been performed to determine the potential surface and molecular electrostatic potential (MEP) of J147, and to examine the correlation between hydrazone J147 and the 1,2,3-triazoles, both bearing a CF 3 substituent. Using MEPs, it was found that the minimum-energy conformation of 4, which is nearly identical to its X-ray structure, is closely related to one of the J147 seven minima.

  6. Aluminum acceptor four particle bound exciton complex in 4H, 6H, and 3C SiC

    NASA Technical Reports Server (NTRS)

    Clemen, L. L.; Devaty, R. P.; Macmillan, M. F.; Yoganathan, M.; Choyke, W. J.; Larkin, D. J.; Powell, J. A.; Edmond, J. A.; Kong, H. S.

    1993-01-01

    Evidence is presented for a four particle acceptor complex in 3C, 6H, and 4H SiC, obtained in low-temperature photoluminescence and cathodoluminescence experiments. The new lines were observed in p-type films lightly doped with aluminum, of 6H, 4H, and 3C SiC grown on the silicon (0001) face of 6H SiC under special conditions. The lines increase in intensity as more aluminum is added during growth. The multiplicity of observed lines is consistent with symmetry-based models similar to those which have been proposed to describe 4A centers in p-type zincblende semiconductors.

  7. Synthesis Of [2h, 13c]M [2h2m 13c], And [2h3,, 13c] Methyl Aryl Sulfones And Sulfoxides

    DOEpatents

    Martinez, Rodolfo A.; Alvarez, Marc A.; Silks, III, Louis A.; Unkefer, Clifford J.; Schmidt, Jurgen G.

    2004-07-20

    The present invention is directed to labeled compounds, [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfones and [.sup.2 H.sub.1, .sup.13 C], [.sup.2 H.sub.2, .sup.13 C] and [.sup.2 H.sub.3, .sup.13 C]methyl aryl sulfoxides, wherein the .sup.13 C methyl group attached to the sulfur of the sulfone or sulfoxide includes exactly one, two or three deuterium atoms and the aryl group is selected from the group consisting of 1-naphthyl, substituted 1-naphthyl, 2-naphthyl, substituted 2-naphthyl, and phenyl groups with the structure: ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4 and R.sub.5 are each independently, hydrogen, a C.sub.1 -C.sub.4 lower alkyl, a halogen, an amino group from the group consisting of NH.sub.2, NHR and NRR' where R and R' are each a C.sub.1 -C.sub.4 lower alkyl, a phenyl, or an alkoxy group. The present invention is also directed to processes of preparing methyl aryl sulfones and methyl aryl sulfoxides.

  8. Computational Study of Pincer Iridium Catalytic Systems: C-H, N-H, and C-C Bond Activation and C-C Coupling Reactions

    NASA Astrophysics Data System (ADS)

    Zhou, Tian

    Computational chemistry has achieved vast progress in the last decades in the field, which was considered to be only experimental before. DFT (density functional theory) calculations have been proven to be able to be applied to large systems, while maintaining high accuracy. One of the most important achievements of DFT calculations is in exploring the mechanism of bond activation reactions catalyzed by organometallic complexes. In this dissertation, we discuss DFT studies of several catalytic systems explored in the lab of Professor Alan S. Goldman. Headlines in the work are: (1) (R4PCP)Ir alkane dehydrogenation catalysts are highly selective and different from ( R4POCOP)Ir catalysts, predicting different rate-/selectivity-determining steps; (2) The study of the mechanism for double C-H addition/cyclometalation of phenanthrene or biphenyl by (tBu4PCP)Ir(I) and ( iPr4PCP)Ir illustrates that neutral Ir(III) C-H addition products can undergo a very facile second C-H addition, particularly in the case of sterically less-crowded Ir(I) complexes; (3) (iPr4PCP)Ir pure solid phase catalyst is highly effective in producing high yields of alpha-olefin products, since the activation enthalpy for dehydrogenation is higher than that for isomerization via an allyl pathway; higher temperatures favor the dehydrogenation/isomerization ratio; (4) (PCP)Ir(H)2(N2H4) complex follows a hydrogen transfer mechanism to undergo both dehydrogenation to form N 2 and H2, as well as hydrogen transfer followed by N-N bond cleavage to form NH3, N2, and H2; (5) The key for the catalytic effect of solvent molecule in CO insertion reaction for RMn(CO)5 is hydrogen bond assisted interaction. The basicity of the solvent determines the strength of the hydrogen bond interaction during the catalytic path and determines the catalytic power of the solvent; and (6) Dehydrogenative coupling of unactivated C-H bonds (intermolecular vinyl-vinyl, intramolecular vinyl-benzyl) is catalyzed by precursors of the

  9. Application of 129I/127I Ratios in Groundwater Studies Conducted at Los Alamos National Laboratory, New Mexico

    NASA Astrophysics Data System (ADS)

    Longmire, P.; Dale, M.; Granzow, K.; Yanicak, S. M.

    2014-12-01

    Los Alamos National Laboratory (LANL) is an operating nuclear site that has released treated effluents from three plutonium-processing facilities since the mid 1940s. The radioisotope 129I (T1/2 = 15.7 Myrs) derived from235U and 239Pu processing at LANL is locally detected in groundwater above background concentrations. This isotope provides a unique tracer for groundwater investigations conducted at LANL that helps to identify source releases linked to groundwater-flow paths in aquifers subject to binary and ternary mixing of natural- and industrial-derived waters containing chromate and other chemicals. Bromide, chlorate, chloride, nitrate, perchlorate, sulfate, and tritium were associated with multiple outfalls at LANL and, therefore, do not provide unique chemical signatures identifying a specific point of release or source. Natural and anthropogenic ratios of 129I/127I measured in groundwater samples collected at LANL were quantified using accelerator mass spectrometry at Purdue Rare Isotope Measurement Laboratory, Purdue University. Anthropogenic ratios of 129I/127I range from 1,531 X 10-15 to 10,323 X 10-15 within perched-intermediate groundwater present in volcanoclastic and basalt aquifers (210 - 216 m depth). Anthropogenic ratios of 129I/127I range from 359 X 10-15 to 4,350 X 10-15 within the regional aquifer (280 m depth) consisting of volcanoclastic sediments of variable hydraulic properties. Local background ratios of 129I/127I have a narrow range of 171 X 10-15 to 378 X 10-15 in the regional aquifer. Dissolved iodide measured in groundwater at LANL is stable dominantly as iodate. Background concentrations of dissolved iodate (0.1 to 33.2 nM) are less variable compared to anthropogenic iodate (8.0 to 246 nM) in groundwater at the site. Variability in concentrations of anthropogenic iodate is controlled by heterogeneous source releases of iodate over time and non-uniform mixing of groundwater in the different aquifers.

  10. 9 CFR 3.129 - Feeding.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... enclosure and shall be placed so as to minimize contamination. Food receptacles shall be kept clean and..., contamination, and deterioration or caking of food. ... Mammals Animal Health and Husbandry Standards § 3.129 Feeding. (a) The food shall be wholesome, palatable...

  11. Photolabeling of Glu-129 of the S-1 subunit of pertussis toxin with NAD

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

    Barbieri, J.T.; Mende-Mueller, L.M.; Rappuoli, R.

    1989-11-01

    UV irradiation was shown to induce efficient transfer of radiolabel from nicotinamide-labeled NAD to a recombinant protein (C180 peptide) containing the catalytic region of the S-1 subunit of pertussis toxin. Incorporation of label from (3H-nicotinamide)NAD was efficient (0.5 to 0.6 mol/mol of protein) relative to incorporation from (32P-adenylate)NAD (0.2 mol/mol of protein). Label from (3H-nicotinamide)NAD was specifically associated with Glu-129. Replacement of Glu-129 with glycine or aspartic acid made the protein refractory to photolabeling with (3H-nicotinamide)NAD, whereas replacement of a nearby glutamic acid, Glu-139, with serine did not. Photolabeling of the C180 peptide with NAD is similar to that observedmore » with diphtheria toxin and exotoxin A of Pseudomonas aeruginosa, in which the nicotinamide portion of NAD is transferred to Glu-148 and Glu-553, respectively, in the two toxins. These results implicate Glu-129 of the S-1 subunit as an active-site residue and a potentially important site for genetic modification of pertussis toxin for development of an acellular vaccine against Bordetella pertussis.« less

  12. The seasonal fluctuations and accumulation of iodine-129 in relation to the hydrogeochemistry of the Wolf Creek Research Basin, a discontinuous permafrost watershed.

    PubMed

    Herod, Matthew N; Li, Tianjiao; Pellerin, André; Kieser, William E; Clark, Ian D

    2016-11-01

    The long lived radioisotope (129)I is a uranium fission product, and an environmental contaminant of the nuclear age. Consequently, it can trace anthropogenic releases of (129)I in watersheds, and has been identified as a potential means to distinguish water sources in discharge (Nimz, 1998). The purpose of this work was to identify the sources and mass input of (129)I and trace the transport, partitioning and mass balance of (129)I over time in a remote watershed. We monitored (129)I and other geochemical and isotope tracers (e.g. δ(14)CDIC, δ(13)CDIC, δ(2)H, δ(18)O, etc.) in precipitation and discharge from the Wolf Creek Research Basin (WCRB), a discontinuous permafrost watershed in the Yukon Territory, Canada, and evaluated the use of (129)I as a water end-member tracer. Radiocarbon and geochemical tracers of weathering show that discharge is comprised of (i) groundwater baseflow that has recharged under open system conditions, (ii) spring freshet meltwater that has derived solutes through closed-system interaction with saturated soils, and (iii) active layer drainage. The abundance of (129)I and the (129)I/(127)I ratio correlated with geochemical tracers suggests varying contributions of these three water end-members to discharge. The (129)I concentration was highest at the onset of freshet, reaching 17.4×10(6) atoms/L, and likely reflects the lack of interaction between meltwater and organic matter at that time. This peak in (129)I was followed by a decline over the summer to its lowest value. Mass balance calculations of the (129)I budget show that the input to the watershed via precipitation is nearly one order of magnitude higher than the output suggesting that such arctic watersheds accumulate nearly 90% of the annual input, primarily in soil organic matter. Temporal variations in discharge (129)I concentrations correlated with changes in discharge water sources suggesting that (129)I is a promising hydrologic tracer, particularly when used in

  13. ADP-ribosylation factor6 regulates both [3H]-noradrenaline and [14C]-glutamate exocytosis through phosphatidylinositol 4,5-bisphosphate.

    PubMed

    Zheng, Qian; Bobich, Joseph A

    2004-10-01

    GTP phosphohydrolase (cell regulating) (EC 3.6.1.47, ADP-ribosylation factor6, ARF6) has been shown to play an important role in different steps of membrane trafficking. It also regulates chromaffin granule exocytosis through phosphatidylcholine phosphatidohydrolase (EC 3.1.4.14, PLD) activation. In this study, the role of ARF6 in neurotransmitter release from both dense-core granules (DCGs) and synaptic vesicles (SVs) in rat brain cortex nerve endings was investigated. We observed that synaptosomal ARF6 is largely particulate but moves to a less easily pelleted compartment upon nerve ending stimulation. We also found that direct inhibition of ARF6 by a specific antibody or interference with ARF6 downstream effects by a myristoylated N-terminal ARF6 peptide both significantly decreased both [3H]-noradrenaline and [14C]-glutamate exocytosis. Addition of phosphatidic acid (PA) and phosphatidylinositol 4,5-bisphosphate (PIP2) partially or completely restored exocytosis. These findings suggest that ARF6 plays important regulatory roles for both DCG and SV exocytosis by activating PLD and ATP:1-phosphatidyl-1D-myo-inositol 4-phosphate 5-phosphotransferase (EC 2.7.1.68, PI4P-5K) to enhance PIP2 synthesis and nerve ending membrane trafficking.

  14. UV-light promoted C-H bond activation of benzene and fluorobenzenes by an iridium(i) pincer complex.

    PubMed

    Hauser, Simone A; Emerson-King, Jack; Habershon, Scott; Chaplin, Adrian B

    2017-03-28

    Iridium(i) carbonyl complex [Ir(2,6-(P t Bu 2 CH 2 ) 2 C 6 H 3 )(CO)] undergoes reversible C-H bond activation of benzene and a series of fluorobenzenes on UV irradiation. Exclusive ortho-selectivity is observed in reactions of fluorobenzene and 1,2-difluorobenzene.

  15. Platinum-Catalyzed, Terminal-Selective C(sp(3))-H Oxidation of Aliphatic Amines.

    PubMed

    Lee, Melissa; Sanford, Melanie S

    2015-10-14

    This Communication describes the terminal-selective, Pt-catalyzed C(sp(3))-H oxidation of aliphatic amines without the requirement for directing groups. CuCl2 is employed as a stoichiometric oxidant, and the reactions proceed in high yield at Pt loadings as low as 1 mol%. These transformations are conducted in the presence of sulfuric acid, which reacts with the amine substrates in situ to form ammonium salts. We propose that protonation of the amine serves at least three important roles: (i) it renders the substrates soluble in the aqueous reaction medium; (ii) it limits binding of the amine nitrogen to Pt or Cu; and (iii) it electronically deactivates the C-H bonds proximal to the nitrogen center. We demonstrate that this strategy is effective for the terminal-selective C(sp(3))-H oxidation of a variety of primary, secondary, and tertiary amines.

  16. Electron-Rich Carboranes. Studies of a Stereochemically Novel System, (CH3)4C4B7H9, and 11-Vertex Arachno Cluster.

    DTIC Science & Technology

    1981-01-01

    FINSTER , R N GRIMES NOGOIR-75C-0305 UNCLASSIFIED TR-37 NL EOMEEEhE OFFICE OF NAVAL RESEARCH CONTRACT NO. i14.-7-C-31 q,4 TECHNICAL REPORT NO. 37L" 0...Electron-Rich Carboranes. Studies of a Stereochemically Novel System, (CH") 4C4 BH 9 , an 11-Vertex Arachno Cluster. .) David C./ Finster aad Russell N...System, (CH3 )4C4B7H9 , an l-Vertex Arachno Cluster 1 David C. Finster and Russell N. Grimes* Contribution from the Department of Chemistry University of

  17. Regioselectivity in the gas-phase reactions of the O- radical anion with ([eta]5-cyclopentadienyl)tricarbonylmanganese(I) and ([eta]5-methylcyclopentadienyl)tricarbonylmanganese(I): formation and structure of C5H5MnO-n and C6H7MnO-n (n = 1, 2) ions

    NASA Astrophysics Data System (ADS)

    van den Berg, Klaas Jan; Ingemann, Steen; Nibbering, Nico M. M.

    1994-06-01

    The gas-phase reactions of the O- ion with ([eta]5-cyclopentadienyl)tricarbonylmanganese(I), CpMn(CO)3, and ([eta]5-methylcyclopentadienyl)tricarbonylmanganese(I), CH3CpMn(CO)3, have been studied with Fourier transform ion cyclotron resonance. The main reactions are (i) proton abstraction, (ii) loss of CO2, and (iii) expulsion of two or three CO molecules from the collision complex. Initial attack on a CO ligand is the main process as indicated by experiments with 18O- and the ion/molecule reactions of the product ions resulting from the loss of three CO molecules with water, aliphatic alcohols, methanethiol and SO2. The attack on a CO ligand followed by loss of three CO molecules is suggested to yield C5H5MnO- ions with a (cyclopentadienone)MnH- structure in the reaction with CpMn(CO)3 and (methylcyclopentadienone)MnH- ions if CH3CpMn(CO)3 is the substrate. A possible mechanism for the process leading to the indicated transformation of the Cp and CH3Cp ligands into C5H4O and CH3C5H3O ligands, respectively, is discussed together with the formation of (fulvene)Mn(OH)- ions following attack of O- on CH3CpMn(CO)3. The (cyclopentadienone)MnH- and (methylcyclopentadienone)MnH- ions react with N2O by oxygen atom abstraction to form C5H5MnO-2 and C6H7MnO-2 ions, respectively.

  18. Glass-bonded iodosodalite waste form for immobilization of 129 I

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

    Chong, Saehwa; Peterson, Jacob A.; Riley, Brian J.

    Immobilization of radioiodine (e.g., 129I, 131I) is an important need for current and future nuclear fuel cycles. For the current work, iodosodalite [Na8(AlSiO4)6I2] was synthesized hydrothermally from metakaolin, NaI, and NaOH. Following hydrothermal treatment, dried unwashed powders were used to make glass-bonded iodosodalite waste forms by heating pressed pellets at 650, 750, or 850 °C with two different types of sodium borosilicate glass binders, i.e., NBS-4 and SA-800. These heat-treated specimens were characterized with X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, thermal analysis, porosity and density measurements, neutron activation analysis, and inductively-coupled plasma mass spectrometry. Themore » pellets mixed with 10 mass% of NBS-4 or SA-800 and heat-treated at 750 °C contained relatively high percentage iodine retention (~44-47 % of the maximum iodine loading) with relatively low porosities, while other pellets with higher percentages iodine retention either contained higher porosity or were not completely sintered. ASTM C1308 chemical durability tests of monolithic specimens showed a large initial release of Na, Al, Si, and I on the first day, possibly from water-soluble salt crystals or non-durable amorphous phases. Release rates of Na and Si were higher than for Al and I, probably due to a poorly durable Na-Si-O phase from the glass bonding matrix. The cumulative normalized release of iodine was 12.5 g m-2 for the first 10 1-d exchanges, suggestive of coherent dissolution. The average release rate from 10-24 days during the 7-d exchange intervals was 0.2336 g m-2 d-1.« less

  19. Synthesis oftrans-3-hexadecenoic acid and oftrans-3-hexadecenoic-1-C(14) acid.

    PubMed

    Knipprath, W G; Stein, R A

    1966-01-01

    Thetrans-3-hexadecenoic acid has been synthesized. Physical properties and chemical degradation prove its identity with the acid earlier isolated from several plant lipids. In the sequence of the synthesis, the introduction of a terminal triple bond into commercially available 1-tetradecene was performed by bromination and debromination with KOH and NaNH(2). Chain elongation by a Grignard reaction with CO(2) gave a carboxylic acid with a triple bond in the 2-position. Reduction with LiAlH(4) yielded the corresponding alcohol, and reduction of the triple to thetrans double bond was accomplished with Na in ethanol. Bromination of the alcohol with PBr(3) and conversion of the bromide to the nitrile with KCN or KC(14)N elongated the carbon chain to the desired length. Methanolysis with HCl in methanol and saponification with KOH formed the acid with acceptable yields, and in the case of the C(14)-labeled carboxyl, group, with high specific activity.

  20. Synergistic Manganese(I) C-H Activation Catalysis in Continuous Flow: Chemoselective Hydroarylation.

    PubMed

    Wang, Hui; Pesciaioli, Fabio; Oliveira, João C A; Warratz, Svenja; Ackermann, Lutz

    2017-11-20

    Chemoselective hydroarylations were accomplished by a novel synergistic Brønsted acid/manganese(I)-catalyzed C-H activation manifold. Thus, alkynes bearing O-leaving groups could, for the first time, be employed for C-H alkenylations without concurrent β-O elimination, thereby setting the stage for versatile late-stage diversifications. Also described is the first manganese-catalyzed C-H activation in continuous flow, thus enabling efficient hydroarylations within only 20 minutes. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Long-term migration of iodine in sedimentary rocks based on iodine speciation and 129I/127I ratio

    NASA Astrophysics Data System (ADS)

    Togo, Y.; Takahashi, Y.; Amano, Y.; Matsuzaki, H.; Suzuki, Y.; Muramatsu, Y.; Iwatsuki, T.

    2012-12-01

    [Introduction] 129I is one of the available indexes of long-term migration of groundwater solutes, because of its long half-life (15.7 million years) and low sorption characteristics. The Horonobe underground research center (Japan Atomic Energy Agency), at which are conducted research and development of fundamental techniques on geological disposal of high-level radioactive waste, is an appropriate site for natural analogue studies, because iodine concentration in groundwater is high in this area. To predict iodine behavior in natural systems, speciation of iodine is essential because of different mobility among each species. In this study, we determined iodine speciation and129I/127I isotope ratios of rock and groundwater samples to investigate long term migration of iodine. [Methods] All rock and groundwater samples were collected at Horonobe underground research center. The region is underlain mainly by Neogene to Quaternary marine sedimentary rocks, the Wakkanai Formation (Wk Fm, siliceous mudstones), and the overlying Koetoi Formation (Kt Fm, diatomaceous mudstones). Iodine species in rock samples were determined by iodine K-edge X-ray absorption near edge structure (SPring-8 BL01B1). Thin sections of rock samples were prepared, and iodine mapping were obtained by micro-XRF analysis (SPring-8 BL37XU). Iodine species (IO3-, I-, and organic I) in groundwater were separately detected by high performance liquid chromatography connected to ICP-MS. The 129I/127I ratios in groundwater and rock samples were measured by accelerator mass spectrometry (MALT, Univ. of Tokyo). Iodine in rock samples were separated by pyrohydrolysis and water extraction. [Results and discussion] Concentration of iodine in groundwater varied widely and was much higher than that of seawater showing a high correlation with that of chlorine (R2 = 0.90). Species of iodine in groundwater was mainly I-. Iodine in rock samples decreased near the boundary between Wk and Kt Fms. Iodine K-edge XANES

  2. Observational infant exploratory [14C]-paracetamol pharmacokinetic microdose/therapeutic dose study with accelerator mass spectrometry bioanalysis

    PubMed Central

    Garner, Colin R; Park, Kevin B; French, Neil S; Earnshaw, Caroline; Schipani, Alessandro; Selby, Andrew M; Byrne, Lindsay; Siner, Sarah; Crawley, Francis P; Vaes, Wouter H J; van Duijn, Esther; deLigt, Rianne; Varendi, Heili; Lass, Jane; Grynkiewicz, Grzegorz; Maruszak, Wioletta; Turner, Mark A

    2015-01-01

    Aims The aims of the study were to compare [14C]-paracetamol ([14C]-PARA) paediatric pharmacokinetics (PK) after administration mixed in a therapeutic dose or an isolated microdose and to develop further and validate accelerator mass spectrometry (AMS) bioanalysis in the 0–2 year old age group. Methods [14C]-PARA concentrations in 10–15 µl plasma samples were measured after enteral or i.v. administration of a single [14C]-PARA microdose or mixed in with therapeutic dose in infants receiving PARA as part of their therapeutic regimen. Results Thirty-four infants were included in the PARA PK analysis for this study: oral microdose (n = 4), i.v. microdose (n = 6), oral therapeutic (n = 6) and i.v. therapeutic (n = 18). The respective mean clearance (CL) values (SDs in parentheses) for these dosed groups were 1.46 (1.00) l h–1, 1.76 (1.07) l h–1, 2.93 (2.08) l h–1 and 2.72 (3.10) l h–1, t1/2 values 2.65 h, 2.55 h, 8.36 h and 7.16 h and dose normalized AUC(0-t) (mg l–1 h) values were 0.90 (0.43), 0.84 (0.57), 0.7 (0.79) and 0.54 (0.26). Conclusions All necessary ethical, scientific, clinical and regulatory procedures were put in place to conduct PK studies using enteral and systemic microdosing in two European centres. The pharmacokinetics of a therapeutic dose (mg kg–1) and a microdose (ng kg–1) in babies between 35 to 127 weeks post-menstrual age. [14C]-PARA pharmacokinetic parameters were within a two-fold range after a therapeutic dose or a microdose. Exploratory studies using doses significantly less than therapeutic doses may offer ethical and safety advantages with increased bionalytical sensitivity in selected exploratory paediatric pharmacokinetic studies. PMID:25619398

  3. Combined Experimental and Computational Study on the Unimolecular Decomposition of JP-8 Jet Fuel Surrogates. I. n-Decane (n-C10H22).

    PubMed

    Zhao, Long; Yang, Tao; Kaiser, Ralf I; Troy, Tyler P; Ahmed, Musahid; Belisario-Lara, Daniel; Ribeiro, Joao Marcelo; Mebel, Alexander M

    2017-02-16

    Exploiting a high temperature chemical reactor, we explored the pyrolysis of helium-seeded n-decane as a surrogate of the n-alkane fraction of Jet Propellant-8 (JP-8) over a temperature range of 1100-1600 K at a pressure of 600 Torr. The nascent products were identified in situ in a supersonic molecular beam via single photon vacuum ultraviolet (VUV) photoionization coupled with a mass spectroscopic analysis of the ions in a reflectron time-of-flight mass spectrometer (ReTOF). Our studies probe, for the first time, the initial reaction products formed in the decomposition of n-decane-including radicals and thermally labile closed-shell species effectively excluding mass growth processes. The present study identified 18 products: molecular hydrogen (H 2 ), C2 to C7 1-alkenes [ethylene (C 2 H 4 ) to 1-heptene (C 7 H 14 )], C1-C3 radicals [methyl (CH 3 ), vinyl (C 2 H 3 ), ethyl (C 2 H 5 ), propargyl (C 3 H 3 ), allyl (C 3 H 5 )], small C1-C3 hydrocarbons [methane (CH 4 ), acetylene (C 2 H 2 ), allene (C 3 H 4 ), methylacetylene (C 3 H 4 )], along with higher-order reaction products [1,3-butadiene (C 4 H 6 ), 2-butene (C 4 H 8 )]. On the basis of electronic structure calculations, n-decane decomposes initially by C-C bond cleavage (excluding the terminal C-C bonds) producing a mixture of alkyl radicals from ethyl to octyl. These alkyl radicals are unstable under the experimental conditions and rapidly dissociate by C-C bond β-scission to split ethylene (C 2 H 4 ) plus a 1-alkyl radical with the number of carbon atoms reduced by two and 1,4-, 1,5-, 1,6-, or 1,7-H shifts followed by C-C β-scission producing alkenes from propene to 1-octene in combination with smaller 1-alkyl radicals. The higher alkenes become increasingly unstable with rising temperature. When the C-C β-scission continues all the way to the propyl radical (C 3 H 7 ), it dissociates producing methyl (CH 3 ) plus ethylene (C 2 H 4 ). Also, at higher temperatures, hydrogen atoms can abstract hydrogen

  4. Electronic Structure and Multisite Basicity of the Pyramidal Phosphinidene-Bridged Dimolybdenum Complex [Mo2(η(5)-C5H5)(μ-κ(1):κ(1),η(5)-PC5H4)(η(6)-C6H3(t)Bu3)(CO)2(PMe3)].

    PubMed

    Albuerne, Isabel G; Alvarez, M Angeles; García, M Esther; García-Vivó, Daniel; Ruiz, Miguel A

    2015-10-19

    The title phosphinidene complex could be sequentially protonated with HBF4·OEt2 or [H(OEt2)2](BAr'4) to give the phosphido-bridged derivatives [Mo2Cp(μ-κ(1):κ(1),η(5)-HPC5H4)(η(6)-HMes*)(CO)2(PMe3)]X and then the hydrides [Mo2Cp(H)(μ-κ(1):κ(1),η(5)-HPC5H4)(η(6)-HMes*)(CO)2(PMe3)]X2 (X = BF4, BAr'4; Ar' = 3,5-C6H3(CF3)2; Mes* = 2,4,6-C6H2(t)Bu3). Density functional theory (DFT) calculations revealed that the most favored site for initial electrophilic attack is the metallocene Mo atom, but attachment of the electrophile to the phosphinidene P atom gives more stable products. This was in agreement with all other reactions investigated, which invariably involved the attachment of the added electrophile at the P site. Thus, the title compound reacted with S8 at 223 K to give the thiophosphinidene-bridged complex [Mo2Cp{μ-κ(1):κ(1),η(5)-P(S)C5H4}(η(6)-HMes*)(CO)2(PMe3)], a poorly stable molecule which reacted with MeI at room temperature to give the corresponding thiolatophosphido derivative, isolated as [Mo2Cp{μ-κ(1):κ(1),η(5)-P(SMe)C5H4}(η(6)-HMes*)(CO)2(PMe3)](BAr'4) (P-S = 2.128(4) Å) after anion exchange with Na(BAr'4). Reaction of the title compound with MeI proceeded smoothly to give the corresponding methylphosphido derivative, isolated analogously as [Mo2Cp{μ-κ(1):κ(1),η(5)-P(Me)C5H4}(η(6)-HMes*)(CO)2(PMe3)](BAr'4). The related complex [Mo2Cp{μ-κ(1):κ(1),η(5)-P(Me)C5H4}(η(6)-HMes*)(CO)2(PMe2Ph)](BAr'4) (P-C(Me) = 1.841(5) Å) could be prepared analogously from the neutral precursor [Mo2Cp{μ-κ(1):κ(1),η(5)-PC5H4}(η(6)-HMes*)(CO)2(PMe2Ph)]. In contrast, reaction of the title complex with ethylene sulfide involved opening of the C2S ring and formation of new P-C and Mo-S bonds (1.886(7) and 2.493(2) Å, respectively), with displacement of the PMe3 ligand, to give the phosphido-thiolato complex [Mo2Cp{μ-κ(2)(P,S):κ(1)P,η(5)-P(C2H4S)C5H4}(η(6)-HMes*)(CO)2]. All these derivatives of the title complex displayed an unusual

  5. Symmetry breaking and spectral considerations of the surprisingly floppy c-C3H radical and the related dipole-bound excited state of c-C3H-

    NASA Astrophysics Data System (ADS)

    Bassett, Matthew K.; Fortenberry, Ryan C.

    2017-06-01

    The C3H radical is believed to be prevalent throughout the interstellar medium and may be involved in the formation of polycyclic aromatic hydrocarbons. C3H exists as both a linear and a cyclic isomer. The C2 v cyclopropenylidenyl radical isomer was detected in the dark molecular cloud TMC-1, and the linear propenylidenyl radical isomer has been observed in various dark molecular clouds. Even though the c-C3H radical has been classified rotationally, the vibrational frequencies of this seemingly important interstellar molecule have never been directly observed. Established, highly accurate quartic force field methodologies are employed here to compute useful geometrical data, spectroscopic constants, and vibrational frequencies. The computed rotational constants are consistent with the experimental results. Consequently, the three a1 (ν1, ν2, and ν3) and one b1 (ν6) anharmonic vibrational frequencies at 3117.7 cm-1, 1564.3 cm-1, 1198.5 cm-1, and 826.7 cm-1, respectively, are reliable predictions for these, as of yet unseen, observables. Unfortunately, the two b2 fundamentals (ν4 and ν5) cannot be treated adequately in the current approach due to a flat and possible double-well potential described in detail herein. The dipole-bound excited state of the anion suffers from the same issues and may not even be bound. However, the trusted fundamental vibrational frequencies described for the neutral radical should not be affected by this deformity and are the first robustly produced for c-C3H. The insights gained here will also be applicable to other structures containing three-membered bare and exposed carbon rings that are surprisingly floppy in nature.

  6. 14 CFR 151.129 - Payments.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... FEDERAL AID TO AIRPORTS Rules and Procedures for Advance Planning and Engineering Proposals § 151.129 Payments. (a) The United States' share of advance planning costs is paid in two installments unless the advance planning grant agreement provides otherwise. Upon request by sponsor, the first payment may be...

  7. Nd2Fe14C-based magnet with better permanent magnetic properties prepared by a simple mechanochemical method

    NASA Astrophysics Data System (ADS)

    Geng, Hongmin; Ji, Yuan; Zhang, Jingjing; Gao, Yuchao; Yan, Yu; Wang, Wenquan; Su, Feng; Du, Xiaobo

    2017-11-01

    Nd2Fe14C-based magnet is prepared by a mechanochemical method, namely high-energy ball-milling Nd2Fe11Bx (x = 0-0.15) alloy in heptane (C7H16), followed by annealing to 850 °C in vacuum. Under the action of high-energy ball-milling, Nd2Fe11Bx react with heptane to form NdH2+δ, Fe-(CB), C, etc. H2 is released and Nd2Fe17, Nd2Fe17Cx (x = 0-3), Nd2Fe14C, Nd carbides and α-Fe are formed in the subsequent annealing. C amount depends on ball-milling time t. Long time ball milling or high C content suppresses the formation of 2:17 phase and favors the formation of 2:14:1 phase in the final products. Excessive ball-milling results in the quick increase of α-Fe. The maximum of magnetically hard Nd2Fe14C is obtained at t = 4 h. For Nd2Fe11 samples, there exists considerable quantity of Nd carbides and α-Fe phase appears earlier and increases rapidly with extending the ball-milling time t. The addition of B element shortens the ball-milling time of the formation of maximum Nd2Fe14C and prominently suppresses the formation of Nd carbide and α-Fe. The optimum magnetic properties, coercivity iHc of 1193.7 kA/m, remanence Mr of 580.9 kA/m, maximum magnetic energy product (BH)max of 91.7 kJ/m3 is approaching to its theoretic value of 99.2 kJ/m3 for isotropic Nd2Fe14C magnet, are obtained in Nd2Fe11B0.06 alloy ball milled for 3.5 h.

  8. Photoabsorption and photoionization cross sections of NH3, PH3, H2S, C2H2, and C2H4 in the VUV region

    NASA Technical Reports Server (NTRS)

    Xia, T. J.; Chien, T. S.; Wu, C. Y. Robert; Judge, D. L.

    1991-01-01

    Using synchrotron radiation as a continuum light source, the photoabsorption and photoionization cross sections of NH3, PH3, H2S, C2H2, and C2H4 have been measured from their respective ionization thresholds to 1060 A. The vibrational constants associated with the nu(2) totally symmetric, out-of-plane bending vibration of the ground electronic state of PH3(+) have been obtained. The cross sections and quantum yields for producing neutral products through photoexcitation of these molecules in the given spectral regions have also been determined. In the present work, autoionization processes were found to be less important than dissociation and predissociation processes in NH3, PH3, and C2H4. Several experimental techniques have been employed in order to examine the various possible systematic errors critically.

  9. Synthesis and X-ray Crystallography of [Mg(H2O)6][AnO2(C2H5COO)3]2 (An = U, Np, or Pu).

    PubMed

    Serezhkin, Viktor N; Grigoriev, Mikhail S; Abdulmyanov, Aleksey R; Fedoseev, Aleksandr M; Savchenkov, Anton V; Serezhkina, Larisa B

    2016-08-01

    Synthesis and X-ray crystallography of single crystals of [Mg(H2O)6][AnO2(C2H5COO)3]2, where An = U (I), Np (II), or Pu (III), are reported. Compounds I-III are isostructural and crystallize in the trigonal crystal system. The structures of I-III are built of hydrated magnesium cations [Mg(H2O)6](2+) and mononuclear [AnO2(C2H5COO)3](-) complexes, which belong to the AB(01)3 crystallochemical group of uranyl complexes (A = AnO2(2+), B(01) = C2H5COO(-)). Peculiarities of intermolecular interactions in the structures of [Mg(H2O)6][UO2(L)3]2 complexes depending on the carboxylate ion L (acetate, propionate, or n-butyrate) are investigated using the method of molecular Voronoi-Dirichlet polyhedra. Actinide contraction in the series of U(VI)-Np(VI)-Pu(VI) in compounds I-III is reflected in a decrease in the mean An═O bond lengths and in the volume and sphericity degree of Voronoi-Dirichlet polyhedra of An atoms.

  10. Infrared absorption of 1-chloro-2-methyl-2-propyl [⋅C(CH3)2CH2Cl] and 2-chloro-2-methylpropyl [⋅CH2C(CH3)2Cl] radicals produced in the addition reactions of Cl with isobutene (i-C4H8) in solid para-hydrogen.

    PubMed

    Chou, Ching-Yin; Lee, Yuan-Pern

    2016-10-07

    The addition reactions of chlorine atom with isobutene (i-C 4 H 8 ) in solid para-hydrogen (p-H 2 ) were investigated with infrared (IR) absorption spectra. When a p-H 2 matrix containing Cl 2 and isobutene was irradiated with ultraviolet light at 365 nm, intense lines in a set at 534.5, 1001.0, 1212.9, 1366.0, 2961.6, and 2934.7 cm -1 , and several weaker others due to the 1-chloro-2-methyl-2-propyl radical, ⋅ C(CH 3 ) 2 CH 2 Cl, and those in a second set including intense ones at 642.7, 799.2, 1098.2, 1371.8, and 3027.3 cm -1 due to the 2-chloro-2-methylpropyl radical, ⋅ CH 2 C(CH 3 ) 2 Cl, appeared; the ratio of ⋅ C(CH 3 ) 2 CH 2 Cl to ⋅ CH 2 C(CH 3 ) 2 Cl was approximately (3 ± 1):1. The observed wavenumbers and relative intensities agree with the vibrational wavenumbers and IR intensities predicted with the B3PW91/aug-cc-pVTZ method. That the Cl atom adds to both carbons of the C=C bond of isobutene with the terminal site slightly favored is consistent with the energies of products predicted theoretically, but is in contrast to the reaction of Cl + propene in solid p-H 2 in which the addition of Cl to mainly the central C atom was previously reported. The role of the p-H 2 matrix in affecting the reaction paths is discussed. Absorption lines of the complex i-C 4 H 8 ⋅Cl 2 and the dichloro-product anti-1,2-dichloro-2-methylpropane, a-CH 2 ClCCl(CH 3 ) 2 , are also characterized.

  11. Controlled growth of 3C-SiC and 6H-SiC films on low-tilt-angle vicinal (0001) 6H-SiC wafers

    NASA Technical Reports Server (NTRS)

    Powell, J. A.; Petit, J. B.; Edgar, J. H.; Jenkins, I. G.; Matus, L. G.

    1991-01-01

    It has been found that, with proper pregrowth surface treatment, 6H-SiC single-crystal films can be grown by chemical vapor deposition (CVD) at 1450 C on vicinal (0001) 6H-SiC with tilt angles as small as 0.1 deg. Previously, tilt angles of greater than 1.5 deg were required to achieve 6H on 6H at this growth temperature. In addition, 3C-SiC could be induced to grow within selected regions on the 6H substrate. the 3C regions contained few (or zero) double-positioning boundaries and a low density of stacking faults. A new growth model is proposed to explain the control of SiC polytype in this epitaxial film growth process.

  12. The measurement of 129I for the cement and the paraffin solidified low and intermediate level wastes (LILWs), spent resin or evaporated bottom from the pressurized water reactor (PWR) nuclear power plants.

    PubMed

    Park, S D; Kim, J S; Han, S H; Ha, Y K; Song, K S; Jee, K Y

    2009-09-01

    In this paper a relatively simple and low cost analysis procedure to apply to a routine analysis of (129)I in low and intermediate level radioactive wastes (LILWs), cement and paraffin solidified evaporated bottom and spent resin, which are produced from nuclear power plants (NPPs), pressurized water reactors (PWR), is presented. The (129)I is separated from other nuclides in LILWs using an anion exchange adsorption and solvent extraction by controlling the oxidation and reduction state and is then precipitated as silver iodide for counting the beta activity with a low background gas proportional counter (GPC). The counting efficiency of GPC was varied from 4% to 8% and it was reversely proportional to the weight of AgI by a self absorption of the beta activity. Compared to a higher pH, the chemical recovery of iodide as AgI was lowered at pH 4. It was found that the chemical recovery of iodide for the cement powder showed a lower trend by increasing the cement powder weight, but it was not affected for the paraffin sample. In this experiment, the overall chemical recovery yield of the cement and paraffin solidified LILW samples and the average weight of them were 67+/-3% and 5.43+/-0.53 g, 70+/-7% and 10.40+/-1.60 g, respectively. And the minimum detectable activity (MDA) of (129)I for the cement and paraffin solidified LILW samples was calculated as 0.070 and 0.036 Bq/g, respectively. Among the analyzed cement solidified LILW samples, (129)I activity concentration of four samples was slightly higher than the MDA and their ranges were 0.076-0.114 Bq/g. Also of the analyzed paraffin solidified LILW samples, five samples contained a little higher (129)I activity concentration than the MDA and their ranges were 0.036-0.107 Bq/g.

  13. Two mixed-ligand lanthanide–hydrazone complexes: [Pr(NCS)3(pbh)2]·H2O and [Nd(NCS)(NO3)(pbh)2(H2O)]NO3·2.33H2O [pbh is N′-(pyridin-2-ylmethylidene)benzo­hydrazide, C13H11N3O

    PubMed Central

    Paschalidis, Damianos G.; Harrison, William T. A.

    2016-01-01

    The gel-mediated syntheses and crystal structures of [N′-(pyridin-2-ylmethylidene-κN)benzohydrazide-κ2 N′,O]tris(thiocyanato-κN)praseodymium(III) mono­hydrate, [Pr(NCS)3(C13H11N3O)2]·H2O, (I), and aqua(nitrato-κ2 O,O′)[N′-(pyri­din-2-ylmethylidene-κN)benzohydrazide-κ2 N′,O](thiocyanato-κN)neo­dym­ium(III) nitrate 2.33-hydrate, [Nd(NCS)(NO3)(C13H11N3O)2(H2O)]NO3·2.33H2O, (II), are reported. The Pr3+ ion in (I) is coordinated by two N,N,O-tridentate N′-(pyridin-2-ylmethylidene)benzohydrazide (pbh) ligands and three N-bonded thio­cyanate ions to generate an irregular PrN7O2 coordination polyhedron. The Nd3+ ion in (II) is coordinated by two N,N,O-tridentate pbh ligands, an N-bonded thio­cyanate ion, a bidentate nitrate ion and a water mol­ecule to generate a distorted NdN5O5 bicapped square anti­prism. The crystal structures of (I) and (II) feature numerous hydrogen bonds, which lead to the formation of three-dimensional networks in each case. PMID:26958385

  14. 21 CFR 129.3 - Definitions.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... CONSUMPTION PROCESSING AND BOTTLING OF BOTTLED DRINKING WATER General Provisions § 129.3 Definitions. For the... inspected and the water sampled, analyzed, and found to be of a safe and sanitary quality according to... means all water which is sealed in bottles, packages, or other containers and offered for sale for human...

  15. Osmoregulation in Lilium Pollen Grains Occurs via Modulation of the Plasma Membrane H+ ATPase Activity by 14-3-3 Proteins1[C][W][OA

    PubMed Central

    Pertl, Heidi; Pöckl, Magdalena; Blaschke, Christian; Obermeyer, Gerhard

    2010-01-01

    To allow successful germination and growth of a pollen tube, mature and dehydrated pollen grains (PGs) take up water and have to adjust their turgor pressure according to the water potential of the surrounding stigma surface. The turgor pressure of PGs of lily (Lilium longiflorum) was measured with a modified pressure probe for simultaneous recordings of turgor pressure and membrane potential to investigate the relation between water and electrogenic ion transport in osmoregulation. Upon hyperosmolar shock, the turgor pressure decreased, and the plasma membrane (PM) hyperpolarizes in parallel, whereas depolarization of the PM was observed with hypoosmolar treatment. An acidification and alkalinization of the external medium was monitored after hyper- and hypoosmotic treatments, respectively, and pH changes were blocked by vanadate, indicating a putative role of the PM H+ ATPase. Indeed, an increase in PM-associated 14-3-3 proteins and an increase in PM H+ ATPase activity were detected in PGs challenged by hyperosmolar medium. We therefore suggest that in PGs the PM H+ ATPase via modulation of its activity by 14-3-3 proteins is involved in the regulation of turgor pressure. PMID:20974894

  16. Chemistry of Renieramycins. Part 14: Total Synthesis of Renieramycin I and Practical Synthesis of Cribrostatin 4 (Renieramycin H).

    PubMed

    Yokoya, Masashi; Kobayashi, Keiichiro; Sato, Mitsuhiro; Saito, Naoki

    2015-08-06

    The first total synthesis of (±)-renieramycin I, which was isolated from the Indian bright blue sponge Haliclona cribricutis, is described. The key step is the selenium oxide oxidation of pentacyclic bis-p-quinone derivative (3) stereo- and regioselectively. We also report a large-scale synthesis of cribrostatin 4 (renieramycin H) via the C3-C4 double bond formation in an early stage based on the Avendaño's protocol, from readily available 1-acetyl-3-(3-methyl-2,4,5-trimethylphenyl)methyl-piperazine-2,5-dione (8) in 18 steps (8.3% overall yield). The synthesis provides unambiguous evidence supporting the original structure of renieramycin I.

  17. Tinnunculite, C5H4N4O3 · 2H2O: Occurrences on the Kola Peninsula and Redefinition and Validation as a Mineral Species

    NASA Astrophysics Data System (ADS)

    Pekov, I. V.; Chukanov, N. V.; Yapaskurt, V. O.; Belakovskiy, D. I.; Lykova, I. S.; Zubkova, N. V.; Shcherbakova, E. P.; Britvin, S. N.; Chervonnyi, A. D.

    2017-12-01

    Based on a study of samples found in the Khibiny (Mt. Rasvumchorr: the holotype) and Lovozero (Mts Alluaiv and Vavnbed) alkaline complexes on the Kola Peninsula, Russia, tinnunculite was approved by the IMA Commission on New Minerals, Nomenclature, and Classification as a valid mineral species (IMA no. 2015-02la) and, taking into account a revisory examination of the original material from burnt dumps of coal mines in the southern Urals, it was redefined as crystalline uric acid dihydrate (UAD), C5H4N4O3 · 2H2O. Tinnunculite is poultry manure mineralized in biogeochemical systems, which could be defined as "guano microdeposits." The mineral occurs as prismatic or tabular crystals up to 0.01 × 0.1 × 0.2 mm in size and clusters of them, as well as crystalline or microglobular crusts. Tinnunculite is transparent or translucent, colorless, white, yellowish, reddish or pale lilac. Crystals show vitreous luster. The mineral is soft and brittle, with a distinct (010) cleavage. D calc = 1.68 g/cm3 (holotype). Tinnunculite is optically biaxial (-), α = 1.503(3), β = 1.712(3), γ = 1.74(1), 2 V obs = 40(10)°. The IR spectrum is given. The chemical composition of the holotype sample (electron microprobe data, content of H is calculated by UAD stoichiometry) is as follows, wt %: 37.5 O, 28.4 C, 27.0 N, 3.8 Hcalc, total 96.7. The empirical formula calculated on the basis of (C + N+ O) = 14 apfu is: C4.99H8N4.07O4.94. Tinnunculite is monoclinic, space group (by analogy with synthetic UAD) P21/ c. The unit cell parameters of the holotype sample (single crystal XRD data) are a = 7.37(4), b = 6.326(16), c = 17.59(4) Å, β = 90(1)°, V = 820(5) Å3, Z = 4. The strongest reflections in the XRD pattern ( d, Å- I[ hkl]) are 8.82-84[002], 5.97-15[011], 5.63-24[102̅, 102], 4.22-22[112], 3.24-27[114̅,114], 3.18-100[210], 3.12-44[211̅, 211], 2.576-14[024].

  18. 1H and 13C NMR spectra of C-6 and C-9 substituted 3-azabicyclco[3.3.1]nonanes.

    PubMed

    Goodall, Kirsten; Brimble, Margaret; Barker, David

    2008-01-01

    The 1H and 13C NMR data for 3-azabicyclo[3.3.1]nonanes with OH and OMe substituents at C-6 and C-9 were measured using 1D (DEPT) and 2D (COSY, HSQC, HMBC, NOESY) experiments. Comparison of this NMR data illustrates the effects of stereochemistry and substitution at these positions. Copyright (c) 2007 John Wiley & Sons, Ltd.

  19. Linear free energy relationships of the 1H and 13C NMR chemical shifts of 3-methylene-2-substituted-1,4-pentadienes

    NASA Astrophysics Data System (ADS)

    Valentić, Nataša V.; Vitnik, Željko; Kozhushkov, Sergei I.; de Meijere, Armin; Ušćumlić, Gordana S.; Juranić, Ivan O.

    2005-06-01

    Linear free energy relationships (LFER) were applied to the 1H and 13C NMR chemical shifts ( δN, N= 1H and 13C, respectively) in the unsaturated backbone of cross-conjugated trienes 3-methylene-2-substituted-1,4-pentadienes. The NMR data were correlated using five different LFER models, based on the mono, the dual and the triple substituent parameter (MSP, DSP and TSP, respectively) treatment. The simple and extended Hammett equations, and the three postulated unconventional LFER models obtained by adaptation of the later, were used. The geometry data, which are needed in Karplus-type and McConnell-type analysis, were obtained using semi-empirical MNDO-PM3 calculations. In correlating the data the TSP approach was more successful than the MSP and DSP approaches. The fact that the calculated molecular geometries allow accurate prediction of the NMR data confirms the validity of unconventional LFER models used. These results suggest the s- cis conformation of the cross-conjugated triene as the preferred one. Postulated unconventional DSP and TSP equations enable the assessment of electronic substituent effects in the presence of other interfering influences.

  20. A novel technique for measurement of thermal rate constants and temperature dependences of dissociative recombination: CO{sub 2}{sup +}, CF{sub 3}{sup +}, N{sub 2}O{sup +}, C{sub 7}H{sub 8}{sup +}, C{sub 7}H{sub 7}{sup +}, C{sub 6}H{sub 6}{sup +}, C{sub 6}H{sub 5}{sup +}, C{sub 5}H{sub 6}{sup +}, C{sub 4}H{sub 4}{sup +}, and C{sub 3}H{sub 3}{sup +}

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

    Fournier, Joseph A.; Shuman, Nicholas S.; Melko, Joshua J.

    A novel technique using a flowing afterglow-Langmuir probe apparatus for measurement of temperature dependences of rate constants for dissociative recombination (DR) is presented. Low ({approx}10{sup 11} cm{sup -3}) concentrations of a neutral precursor are added to a noble gas/electron afterglow plasma thermalized at 300-500 K. Charge exchange yields one or many cation species, each of which may undergo DR. Relative ion concentrations are monitored at a fixed reaction time while the initial plasma density is varied between 10{sup 9} and 10{sup 10} cm{sup -3}. Modeling of the decrease in concentration of each cation relative to the non-recombining noble gas cationmore » yields the rate constant for DR. The technique is applied to several species (O{sub 2}{sup +}, CO{sub 2}{sup +}, CF{sub 3}{sup +}, N{sub 2}O{sup +}) with previously determined 300 K values, showing excellent agreement. The measurements of those species are extended to 500 K, with good agreement to literature values where they exist. Measurements are also made for a range of C{sub n}H{sub m}{sup +} (C{sub 7}H{sub 7}{sup +}, C{sub 7}H{sub 8}{sup +}, C{sub 5}H{sub 6}{sup +}, C{sub 4}H{sub 4}{sup +}, C{sub 6}H{sub 5}{sup +}, C{sub 3}H{sub 3}{sup +}, and C{sub 6}H{sub 6}{sup +}) derived from benzene and toluene neutral precursors. C{sub n}H{sub m}{sup +} DR rate constants vary from 8-12 Multiplication-Sign 10{sup -7} cm{sup 3} s{sup -1} at 300 K with temperature dependences of approximately T{sup -0.7}. Where prior measurements exist these results are in agreement, with the exception of C{sub 3}H{sub 3}{sup +} where the present results disagree with a previously reported flat temperature dependence.« less

  1. 17 CFR 240.3a12-9 - Exemption of certain direct participation program securities from the arranging provisions of...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Exemption of certain direct participation program securities from the arranging provisions of sections 7(c) and 11(d)(1). 240.3a12-9 Section 240.3a12-9 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) GENERAL...

  2. Synthesis of cationic iridium(I) complexes of water-soluble phosphine ligands, [Ir(CO)(TPPMS){sub 3}]CF{sub 3}SO{sub 3}, [Ir(CO)(H{sub 2}O)(TPPTS){sub 2}]CF{sub 3}SO{sub 3}, and [Ir(CO){sub 2}(TPPMS){sub 3}]ClO{sub 4} (TPPMS = PPh{sub 2}(m-C{sub 6}H{sub 4}SO{sub 3}K), TPPTS = P(m-C{sub 6}H{sub 4}SO{sub 3}Na){sub 3})

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

    Paterniti, D.P.; Francisco, L.W.; Atwood, J.D.

    Several new water-soluble iridium(I) complexes were synthesized and their reactivities with small molecules (H{sub 2} or CO) in polar solvents (DMSO or H{sub 2}O) examined. Reaction of H{sub 2} with [Ir(CO)(TPPMS){sub 3}]CF{sub 3}SO{sub 3} (TPPMS = P(C{sub 6}H{sub 5}){sub 2}(m-C{sub 6}H{sub 4}SO{sub 3}K)) in DMSO or H{sub 2}O produces [cis,mer-Ir(CO)(H){sub 2}(TPPMS){sub 3}]CF{sub 3}SO{sub 3}, while the reaction of CO with [Ir(CO)(TPPMS){sub 3}]-CF{sub 3}SO{sub 3} in water yields [Ir(CO){sub 2}(TPPMS){sub 3}]CF{sub 3}SO{sub 3}. Carbonylation of [Ir(CO){sub 2}(TPPMS){sub 3}]ClO{sub 4} in DMSO produces [Ir(CO){sub 3}(TPPMS){sub 2}]ClO{sub 4} and TPPMS; no reaction is observed in H{sub 2}O. Hydrogenation of [Ir(CO){sub 2}(TPPMS){sub 3}]ClO{sub 4}more » in DMSO or H{sub 2}O yields [cis,mer-Ir(CO)(H){sub 2}(TPPMS){sub 3}]ClO{sub 4}, while reaction of H{sub 2} with an aqueous solution of [Ir(CO)(H{sub 2}O)(TPPTS){sub 2}]CF{sub 3}SO{sub 3} produces [Ir(CO)(H{sub 2}O)(H){sub 2}(TPPTS){sub 2}]CF{sub 3}SO{sub 3}. Reaction of trans-Ir(CO)ClL{sub 2} (L = TPPMS or TPPTS) with excess L in H{sub 2}O produces [Ir(CO)L{sub 3}]Cl, while no reaction occurs in DMSO, [Ir(CO){sub 3}(TPPMS){sub 2}]Cl reacts irreversibly with TPPMS in H{sub 2}O to produce [Ir(CO){sub 2}-(TPPMS){sub 3}]Cl.« less

  3. Characterization of the Minimum Energy Paths for the Ring Closure Reactions of C4H3 with Acetylene

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.

    1995-01-01

    The ring closure reaction of C4H3 with acetylene to give phenyl radical is one proposed mechanism for the formation of the first aromatic ring in hydrocarbon combustion. There are two low-lying isomers of C4H3; 1-dehydro-buta-l-ene-3-yne (n-C4H3) and 2-dehydro-buta-l-ene-3-yne (iso-C4H3). It has been proposed that only n-C4H3 reacts with acetylene to give phenyl radical, and since iso-C4H3 is more stable than n-C4H3, formation of phenyl radical by this mechanism is unlikely. We report restricted Hartree-Fock (RHF) plus singles and doubles configuration interaction calculations with a Davidson's correction (RHF+1+2+Q) using the Dunning correlation consistent polarized valence double zeta basis set (cc-pVDZ) for stationary point structures along the reaction pathway for the reactions of n-C4H3 and iso-C4H3 with acetylene. n-C4H3 plus acetylene (9.4) has a small entrance channel barrier (17.7) (all energetics in parentheses are in kcal/mol with respect to iso-C4H3 plus acetylene) and the subsequent closure steps leading to phenyl radical (-91.9) are downhill with respect to the entrance channel barrier. Iso-C4H3 Plus acetylene also has an entrance channel barrier (14.9) and there is a downhill pathway to 1-dehydro-fulvene (-55.0). 1-dehydro-fulvene can rearrange to 6-dehydro-fulvene (-60.3) by a 1,3-hydrogen shift over a barrier (4.0), which is still below the entrance channel barrier, from which rearrangement to phenyl radical can occur by a downhill pathway. Thus, both n-C4H3 and iso-C4H3 can react with acetylene to give phenyl radical with small barriers.

  4. Trapping-mediated dissociative chemisorption of C3H8 and C3D8 on Ir(110)

    NASA Astrophysics Data System (ADS)

    Kelly, D.; Weinberg, W. H.

    1996-07-01

    We have employed molecular beam techniques to investigate the molecular trapping and trapping-mediated dissociative chemisorption of C3H8 and C3D8 on Ir(110) at low beam translational energies, Ei≤5 kcal/mol, and surface temperatures, Ts, from 85 to 1200 K. For Ts=85 K, C3H8 is molecularly adsorbed on Ir(110) with a trapping probability, ξ, equal to 0.94 at Ei=1.6 kcal/mol and ξ=0.86 at Ei=5 kcal/mol. At Ei=1.9 kcal/mol and Ts=85 K, ξ of C3D8 is equal to 0.93. From 150 K to approximately 700 K, the initial probabilities of dissociative chemisorption of propane decrease with increasing Ts. For Ts from 700 to 1200 K, however, the initial probability of dissociative chemisorption maintains the essentially constant value of 0.16. These observations are explained within the context of a kinetic model which includes both C-H (C-D) and C-C bond cleavage. Below 450 K propane chemisorption on Ir(110) arises essentially solely from C-H (C-D) bond cleavage, an unactivated mechanism (with respect to a gas-phase energy zero) for this system, which accounts for the decrease in initial probabilities of chemisorption with increasing Ts. With increasing Ts, however, C-C bond cleavage, the activation energy of which is greater than the desorption energy of physically adsorbed propane, increasingly contributes to the measured probability of dissociative chemisorption. The activation energies, referenced to the bottom of the physically adsorbed molecular well, for C-H and C-C bond cleavage for C3H8 on Ir(110) are found to be Er,CH=5.3±0.3 kcal/mol and Er,CC=9.9±0.6 kcal/mol, respectively. The activation energies for C-D and C-C bond cleavage for C3D8 on Ir(110) are 6.3±0.3 kcal/mol and 10.5±0.6 kcal/mol, respectively. The desorption activation energy of propane from Ir(110) is approximately 9.5 kcal/mol. These activation energies are compared to activation energies determined recently for ethane and propane adsorption on Ir(111), Ru(001), and Pt(110)-(1×2), and ethane

  5. 129I in the environment of the La Hague nuclear fuel reprocessing plant--from sea to land.

    PubMed

    Fréchou, C; Calmet, D

    2003-01-01

    In recent years, particular attention was paid to the long-lived radionuclides discharged with authorized low-level radioactive liquid and gaseous effluents by the nuclear spent fuel reprocessing plants of La Hague and Sellafield. The knowledge of (129)I (half-life=15.7 x 10(6) a) distribution in the environment is required to assess the radiological impact to the environment and population living in the area under the direct influence of La Hague NRP discharges. Measurement difficulties of (129)I in environmental matrices, where it is usually present at trace level, limited data published on (129)I activity levels in the European and more particularly in the French territory. Studies conducted to qualify a new alternative measurement method, direct gamma-X spectrometry with experimental self-absorption correction, led to test samples collected in the La Hague marine and terrestrial environment : seaweeds, lichens, grass, bovine thyroids, etc. All these results, often already published separately for analytical purposes and treated for intercomparison exercises, are presented here together in a radioecological manner. The levels of (129)I activity and (129)I/(127)I ratios in these samples show the spatial and temporal influence of the La Hague NRP in its local near-field environment as well as at the regional scale along the French Channel coast.

  6. Structural phase transition causing anomalous photoluminescence behavior in perovskite (C6H11NH3)2[PbI4

    NASA Astrophysics Data System (ADS)

    Yangui, A.; Pillet, S.; Mlayah, A.; Lusson, A.; Bouchez, G.; Triki, S.; Abid, Y.; Boukheddaden, K.

    2015-12-01

    Optical and structural properties of the organic-inorganic hybrid perovskite-type (C6H11NH3)2[PbI4] (abbreviated as C6PbI4) were investigated using optical absorption, photoluminescence (PL), and x-ray diffraction measurements. Room temperature, optical absorption measurements, performed on spin-coated films of C6PbI4, revealed two absorption bands at 2.44 and 3.21 eV. Upon 325 nm (3.815 eV) laser irradiation, strong green PL emission peaks were observed at 2.41 eV (P1) and 2.24 eV (P2) and assigned to free and localized excitons, respectively. The exciton binding energy was estimated at 356 meV. At low temperature, two additional emission bands were detected at 2.366 eV (P3) and a large band (LB) at 1.97 eV. The former appeared only below 40 K and the latter emerged below 130 K. The thermal dependence of the PL spectra revealed an abnormal behavior accompanied by singularities in the peak positions and intensities at 40 and 130 K. X-ray diffraction studies performed on powder and single crystals as a function of temperature evidenced significant changes of the interlayer spacing at 50 K and ˜138 K. Around 138 K, a commensurate to incommensurate structural phase transition occurred on cooling. It involves a symmetry breaking leading to a distortion of the PbI6 octahedron. The resulting incommensurate spatial modulation of the Pb-I distances (and Pb-I-Pb angles) causes a spatial modulation of the band gap, which is at the origin of the emergence of the LB below ˜130 K and the anomalous behavior of the position of P1 below 130 K. The change of the interlayer spacing in the 40-50 K range may in turn be related to the significant decrease of the intensity of P2 and the maximum emission of the LB. These results underline the intricate character of the structural and the PL properties of the hybrid perovskites; understanding such properties should benefit to the design of optoelectronic devices with targeted properties.

  7. Structural phase transition causing anomalous photoluminescence behavior in perovskite (C6H11NH3)2[PbI4].

    PubMed

    Yangui, A; Pillet, S; Mlayah, A; Lusson, A; Bouchez, G; Triki, S; Abid, Y; Boukheddaden, K

    2015-12-14

    Optical and structural properties of the organic-inorganic hybrid perovskite-type (C6H11NH3)2[PbI4] (abbreviated as C6PbI4) were investigated using optical absorption, photoluminescence (PL), and x-ray diffraction measurements. Room temperature, optical absorption measurements, performed on spin-coated films of C6PbI4, revealed two absorption bands at 2.44 and 3.21 eV. Upon 325 nm (3.815 eV) laser irradiation, strong green PL emission peaks were observed at 2.41 eV (P1) and 2.24 eV (P2) and assigned to free and localized excitons, respectively. The exciton binding energy was estimated at 356 meV. At low temperature, two additional emission bands were detected at 2.366 eV (P3) and a large band (LB) at 1.97 eV. The former appeared only below 40 K and the latter emerged below 130 K. The thermal dependence of the PL spectra revealed an abnormal behavior accompanied by singularities in the peak positions and intensities at 40 and 130 K. X-ray diffraction studies performed on powder and single crystals as a function of temperature evidenced significant changes of the interlayer spacing at 50 K and ∼138 K. Around 138 K, a commensurate to incommensurate structural phase transition occurred on cooling. It involves a symmetry breaking leading to a distortion of the PbI6 octahedron. The resulting incommensurate spatial modulation of the Pb-I distances (and Pb-I-Pb angles) causes a spatial modulation of the band gap, which is at the origin of the emergence of the LB below ∼130 K and the anomalous behavior of the position of P1 below 130 K. The change of the interlayer spacing in the 40-50 K range may in turn be related to the significant decrease of the intensity of P2 and the maximum emission of the LB. These results underline the intricate character of the structural and the PL properties of the hybrid perovskites; understanding such properties should benefit to the design of optoelectronic devices with targeted properties.

  8. 14-3-3 α and 14-3-3 ζ contribute to immune responses in planarian Dugesia japonica.

    PubMed

    Lu, Qingqing; Wu, Suge; Zhen, Hui; Deng, Hongkuan; Song, Qian; Ma, Kaifu; Cao, Zhonghong; Pang, Qiuxiang; Zhao, Bosheng

    2017-06-05

    14-3-3 proteins are a family of highly conserved acidic proteins that regulate cellular processes. They act as a kind of important signaling molecules taking part in many crucial decisions throughout the development process. We have isolated and characterized two members of the 14-3-3 family, namely, Dj14-3-3 α and Dj14-3-3 ζ in the planarian Dugesia japonica. The Dj14-3-3 α and ζ genes encode polypeptides of 260 and 255 amino acids respectively. We have proved that the Dj14-3-3 α and ζ genes were especially expressed in the pharynx in adult and regenerating planarians by in situ hybridization and they were not involved in regeneration process. Besides, Dj14-3-3 α and ζ genes can compensate each other in planarians by RNA interference. The Dj14-3-3 α and ζ were significantly up-regulated expression when planarians were stimulated with the pathogen-associated molecular patterns including lipopolysaccharide (LPS), peptidoglycan (PGN), β-Glu and Poly (I:C), indicating that the Dj14-3-3 α and ζ may be involved in the immune responses. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Distribution and biomarker of carbon-14 labeled fullerene C60 ([(14) C(U)]C60 ) in pregnant and lactating rats and their offspring after maternal intravenous exposure.

    PubMed

    Snyder, Rodney W; Fennell, Timothy R; Wingard, Christopher J; Mortensen, Ninell P; Holland, Nathan A; Shannahan, Jonathan H; Pathmasiri, Wimal; Lewin, Anita H; Sumner, Susan C J

    2015-12-01

    A comprehensive distribution study was conducted in pregnant and lactating rats exposed to a suspension of uniformly carbon-14 labeled C60 ([(14) C(U)]C60 ). Rats were administered [(14) C(U)]C60 (~0.2 mg [(14) C(U)]C60 kg(-1) body weight) or 5% polyvinylpyrrolidone (PVP)-saline vehicle via a single tail vein injection. Pregnant rats were injected on gestation day (GD) 11 (terminated with fetuses after either 24 h or 8 days), GD15 (terminated after 24 h or 4 days), or GD18 (terminated after 24 h). Lactating rats were injected on postnatal day 8 and terminated after 24 h, 3 or 11 days. The distribution of radioactivity in pregnant dams was influenced by both the state of pregnancy and time of termination after exposure. The percentage of recovered radioactivity in pregnant and lactating rats was highest in the liver and lungs. Radioactivity was quantitated in over 20 tissues. Radioactivity was found in the placenta and in fetuses of pregnant dams, and in the milk of lactating rats and in pups. Elimination of radioactivity was < 2% in urine and feces at each time point. Radioactivity remained in blood circulation up to 11 days after [(14) C(U)]C60 exposure. Biomarkers of inflammation, cardiovascular injury and oxidative stress were measured to study the biological impacts of [(14) C(U)]C60 exposure. Oxidative stress was elevated in female pups of exposed dams. Metabolomics analysis of urine showed that [(14) C(U)]C60 exposure to pregnant rats impacted the pathways of vitamin B, regulation of lipid and sugar metabolism and aminoacyl-tRNA biosynthesis. This study demonstrated that [(14) C(U)]C60 crosses the placenta at all stages of pregnancy examined, and is transferred to pups via milk. Copyright © 2015 John Wiley & Sons, Ltd.

  10. Microbial degradation of [C14C]polystyrene and 1,3-diphenylbutane.

    PubMed

    Sielicki, M; Focht, D D; Martin, J P

    1978-07-01

    Microbial degradation of [beta-14C]polystyrene and 1,3-diphenylbutane, a compound structurally representing the smallest repeating unit of styrene (dimer), was investigated in soil and liquid enrichment cultures. Degradation rates in soil, as determined by 14CO2 evolution from applied [14C]polystyrene, varied from 1.5 to 3.0% for a 4-month period. Although relatively low, these percentages were 15 to 30 times greater than values previously reported. Enrichment cultures, containing 1,3-diphenylbutane as the only carbon souce, were used to determine the mechanisms of microbial oxidation of the polymer chain ends. Metabolism of 1,3-diphenylbutane appeared to involve the attack by a monooxygenease to form 2-phenyl-4-hydroxyphenylbutane followed by a further oxidation and subsequent fission of the benzene ring to yield 4-phenylvaleric acid and an unidentified 5-carbon fragment via the classic meta-fission pathway. Phenylacetic acid was probably formed from 4-phenylvaleric acid by subsequent beta-oxidation of the side chain, methyl-oxidation and decarboxylation. An initial examination of the population of microorganisms in the diphenylbutane enrichment cultures indicated that these oxidative reactions are carried out by common soil microorganism of the genera Bacillus, Pseudomonas, Micrococcus, and Nocardia.

  11. Cleavage of sp3 C-O bonds via oxidative addition of C-H bonds.

    PubMed

    Choi, Jongwook; Choliy, Yuriy; Zhang, Xiawei; Emge, Thomas J; Krogh-Jespersen, Karsten; Goldman, Alan S

    2009-11-04

    (PCP)Ir (PCP = kappa(3)-C(6)H(3)-2,6-[CH(2)P(t-Bu)(2)](2)) is found to undergo oxidative addition of the methyl-oxygen bond of electron-poor methyl aryl ethers, including methoxy-3,5-bis(trifluoromethyl)benzene and methoxypentafluorobenzene, to give the corresponding aryloxide complexes (PCP)Ir(CH(3))(OAr). Although the net reaction is insertion of the Ir center into the C-O bond, density functional theory (DFT) calculations and a significant kinetic isotope effect [k(CH(3))(OAr)/k(CD(3))(OAr) = 4.3(3)] strongly argue against a simple insertion mechanism and in favor of a pathway involving C-H addition and alpha-migration of the OAr group to give a methylene complex followed by hydride-to-methylene migration to give the observed product. Ethoxy aryl ethers, including ethoxybenzene, also undergo C-O bond cleavage by (PCP)Ir, but the net reaction in this case is 1,2-elimination of ArO-H to give (PCP)Ir(H)(OAr) and ethylene. DFT calculations point to a low-barrier pathway for this reaction that proceeds through C-H addition of the ethoxy methyl group followed by beta-aryl oxide elimination and loss of ethylene. Thus, both of these distinct C-O cleavage reactions proceed via initial addition of a C(sp(3))-H bond, despite the fact that such bonds are typically considered inert and are much stronger than C-O bonds.

  12. Taste-Evoked Responses to Sweeteners in the Nucleus of the Solitary Tract Differ between C57BL/6ByJ and 129P3/J Mice

    PubMed Central

    McCaughey, Stuart A.

    2008-01-01

    C57BL/6ByJ (B6) and 129P3/J (129) mice have different alleles of Tas1r3, which is thought to influence gustatory transduction of sweeteners, but studies have provided conflicting results regarding differences in sweetness perception between these strains. Single-unit taste-evoked activity was measured in the nucleus of the solitary tract (NST) in anesthetized B6 and 129 mice to address this controversy and to provide the first electrophysiological characterization of this nucleus in mice. Neurons had properties similar to those of NST cells in other species, including mean breadth-of-tuning of 0.8 ± 0.0. There were no strain differences in neural responses at 600 or 900 ms after onset, but, with a 5 s evoked period, responses to the sweeteners sucrose, maltose, acesulfame-K, SC-45647, and D-phenylalanine were significantly larger in B6 relative to 129 mice. The strains did not differ in their mean response to NaSaccharin, but it evoked an across-neuron pattern of activity that was more similar to that of sucrose and less similar to that of NaCl in B6 mice compared with 129 mice. Neurons were classified as sucrose, NaCl, or HCl responsive, with the former more common in B6 than 129 mice. Relative to other neurons, sucrose-responsive cells had delayed but more sustained sweetener responses in both strains. The results suggest that B6 mice perceive some sweeteners as more intense, but NaSaccharin as sweeter and less salty, relative to 129 mice. Furthermore, activity evoked by sweeteners includes a phasic response sent to different NST cells than a later tonic response, and only the latter differs between B6 and 129 mice. PMID:17202470

  13. Downregulation of p-coumaroyl quinate/shikimate 3'-hydroxylase (C3'H) or cinnamate-4-hydrolylase (C4H) in Eucalyptus urophylla x Eucalyptus grandis leads to increased extractability

    DOE PAGES

    Ziebell, Angela; Gjersing, Erica; Hinchee, Maud; ...

    2016-01-20

    Lignin reduction through breeding and genetic modification has the potential to reduce costs in biomass processing in pulp and paper, forage, and lignocellulosic ethanol industries. Here, we present detailed characterization of the extractability and lignin structure of Eucalyptus urophylla x Eucalyptus grandis RNAi downregulated in p-coumaroyl quinate/shikimate 3'-hydroxylase (C3'H) or cinnamate-4-hydroxylase (C4H). Both the C3'H and C4H downregulated lines were found to have significantly higher extractability when exposed to NaOH base extraction, indicating altered cell wall construction. The molecular weight of isolated lignin was measured and lignin structure was determined by HSQC NMR-based lignin subunit analysis for control and themore » C3'H and C4H downregulated lines. The slight reductions in average molecular weights of the lignin isolated from the transgenic lines (C3'H = 7000, C4H = 6500, control = 7300) does not appear to explain the difference in extractability. The HSQC NMR-based lignin subunit analysis showed increases in H lignin content for the C3'H but only slight differences in the lignin subunit structure of the C3'H and C4H downregulated lines when compared to the control. The greatest difference between the C3'H and C4H downregulated lines is the total lignin content; therefore, it appears that overall lowered lignin content contributes greatly to reduced recalcitrance and increased extractability of cell wall biopolymers. Furthermore, studies will be conducted to determine how the reduction in lignin content creates a less rigid cell wall that is more prone to extraction and sugar release.« less

  14. Human factors evaluation of TSO-C129A GPS receivers

    DOT National Transportation Integrated Search

    1998-10-22

    This report documents an evaluation of the usability of TSO-C129a-certified Global Positioning System (GPS) receivers. Bench and flight tests were conducted on six GPS receivers. The evaluations covered 23 flight tasks. Both subjective and objective ...

  15. Synthesis,and structural characterization of [(CH3(C5H4N))Ga(SCH2(CO)O)]-[(4-MepyH)]+, a novel Ga(III) five coordinate complex.

    NASA Technical Reports Server (NTRS)

    Banger, Kulbinder K.; Duraj, Stan A.; Fanwic, Phillp E.; Hepp, Aloysius F.; Martuch, Robert A.

    2003-01-01

    The synthesis and structural characterization of a novel ionic Ga(III) five coordinate complex [{CH3(C5H4N)}Ga(SCH2(CO)O)2]-[(4-MepyH)]+, (4-Mepy = CH3(C5H5N)) from the reaction between Ga2Cl4 with sodium mercapto-acetic acid in 4-methylpyridine is described. Under basic reaction conditions the mercapto ligand is found to behave as a 2e- bidentate ligand. Single crystal X-ray diffraction studies show the complex to have a distorted square pyramidal geometry with the [(-SCH2(CO)CO-)] ligands in a trans conformation. The compound crystallizes in the P2(sub 1)/c (No. 14) space group with a = 7.7413(6) A, b = 16.744(2) A, c = 14.459(2) A, V = 1987.1(6) A(sup 3), R(F) = 0.032 and R(sub w) = 0.038.

  16. The neuroinvasive profiles of H129 (herpes simplex virus type 1) recombinants with putative anterograde-only transneuronal spread properties.

    PubMed

    Wojaczynski, Gregory J; Engel, Esteban A; Steren, Karina E; Enquist, Lynn W; Patrick Card, J

    2015-01-01

    The use of viruses as transneuronal tracers has become an increasingly powerful technique for defining the synaptic organization of neural networks. Although a number of recombinant alpha herpesviruses are known to spread selectively in the retrograde direction through neural circuits only one strain, the H129 strain of herpes simplex virus type 1, is reported to selectively spread in the anterograde direction. However, it is unclear from the literature whether there is an absolute block or an attenuation of retrograde spread of H129. Here, we demonstrate efficient anterograde spread, and temporally delayed retrograde spread, of H129 and three novel recombinants. In vitro studies revealed no differences in anterograde and retrograde spread of parental H129 and its recombinants through superior cervical ganglion neurons. In vivo injections of rat striatum revealed a clear bias of anterograde spread, although evidence of deficient retrograde transport was also present. Evidence of temporally delayed retrograde transneuronal spread of H129 in the retina was observed following injection of the lateral geniculate nucleus. The data also demonstrated that three novel recombinants efficiently express unique fluorescent reporters and have the capacity to infect the same neurons in dual infection paradigms. From these experiments we conclude that H129 and its recombinants not only efficiently infect neurons through anterograde transneuronal passage, but also are capable of temporally delayed retrograde transneuronal spread. In addition, the capacity to produce dual infection of projection targets following anterograde transneuronal passage provides an important addition to viral transneuronal tracing technology.

  17. The Neuroinvasive Profiles of H129 (Herpes Simplex Virus Type 1) Recombinants with Putative Anterograde-Only Transneuronal Spread Properties

    PubMed Central

    Wojaczynski, Gregory J.; Engel, Esteban A.; Steren, Karina E.; Enquist, Lynn W.; Card, J. Patrick

    2014-01-01

    The use of viruses as transneuronal tracers has become an increasingly powerful technique for defining the synaptic organization of neural networks. Although a number of recombinant alpha herpesviruses are known to spread selectively in the retrograde direction through neural circuits only one strain, the H129 strain of herpes simplex virus type 1, is reported to selectively spread in the anterograde direction. However, it is unclear from the literature whether there is an absolute block or an attenuation of retrograde spread of H129. Here we demonstrate efficient anterograde spread, and temporally delayed retrograde spread, of H129 and three novel recombinants. In vitro studies revealed no differences in anterograde and retrograde spread of parental H129 and its recombinants through superior cervical ganglion neurons. In vivo injections of rat striatum revealed a clear bias of anterograde spread, although evidence of deficient retrograde transport was also present. Evidence of temporally delayed retrograde transneuronal spread of H129 in the retina was observed following injection of the lateral geniculate nucleus. The data also demonstrated that three novel recombinants efficiently express unique fluorescent reporters and have the capacity to infect the same neurons in dual infection paradigms. From these experiments we conclude that H129 and its recombinants efficiently infect neurons through anterograde transneuronal passage, but also are capable of temporally delayed retrograde transneuronal spread. In addition, the capacity to produce dual infection of projection targets following anterograde transneuronal passage provides an important addition to viral transneuronal tracing technology. PMID:24585022

  18. Fluoroethoxy-1,4-diphenethylpiperidine and piperazine derivatives: Potent and selective inhibitors of [3H]dopamine uptake at the vesicular monoamine transporter-2.

    PubMed

    Hankosky, Emily R; Joolakanti, Shyam R; Nickell, Justin R; Janganati, Venumadhav; Dwoskin, Linda P; Crooks, Peter A

    2017-12-15

    A small library of fluoroethoxy-1,4-diphenethyl piperidine and fluoroethoxy-1,4-diphenethyl piperazine derivatives were designed, synthesized and evaluated for their ability to inhibit [ 3 H]dopamine (DA) uptake at the vesicular monoamine transporter-2 (VMAT2) and dopamine transporter (DAT), [ 3 H]serotonin (5-HT) uptake at the serotonin transporter (SERT), and [ 3 H]dofetilide binding at the human-ether-a-go-go-related gene (hERG) channel. The majority of the compounds exhibited potent inhibition of [ 3 H]DA uptake at VMAT2, Ki changes in the nanomolar range (K i  = 0.014-0.073 µM). Compound 15d exhibited the highest affinity (K i  = 0.014 µM) at VMAT2, and had 160-, 5-, and 60-fold greater selectivity for VMAT2 vs. DAT, SERT and hERG, respectively. Compound 15b exhibited the greatest selectivity (>60-fold) for VMAT2 relative to all the other targets evaluated, and 15b had high affinity for VMAT2 (K i  = 0.073 µM). Compound 15b was considered the lead compound from this analog series due to its high affinity and selectivity for VMAT2. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Multi-level study of C3H2: The first interstellar hydrocarbon ring

    NASA Technical Reports Server (NTRS)

    Madden, S. C.; Irvine, W. M.; Matthews, H. E.; Avery, L. W.

    1986-01-01

    Cyclic species in the interstellar medium have been searched for almost since the first detection of interstellar polyatomic molecules. Eleven different C3H2 rotational transitions were detected; 9 of which were studied in TMC-1, a nearby dark dust cloud, are shown. The 1 sub 10 yields 1 sub 01 and 2 sub 20 yields 2 sub 11 transitions were observed with the 43 m NRAO telescope, while the remaining transitions were detected with the 14 m antenna of the Five College Radio Observatory (FCRAO). The lines detected in TMC-1 have energies above the ground state ranging from 0.9 to 17.1 K and consist of both ortho and para species. Limited maps were made along the ridge for several of the transitions. The HC3N J = 2 yields 1 transition were mapped simultaneously with the C3H2 1 sub 10 yields 1 sub 01 line and therefore can compare the distribution of this ring with a carbon chain in TMC-1. C3H2 is distributed along a narrow ridge with a SE - NW extension which is slightly more extended than the HC2N J = 2 yields 1. Gaussian fits gives a FWHP extension of 8'5 for C3H2 while HC3N has a FWHP of 7'. The data show variations of the two velocity components along the ridge as a function of transition. Most of the transitions show a peak at the position of strongest HC3N emission while the 2 sub 21 yields 2 sub 10 transition shows a peak at the NH3 position.

  20. C 3-symmetric opioid scaffolds are pH-responsive DNA condensation agents

    PubMed Central

    McStay, Natasha; Molphy, Zara; Coughlan, Alan; Cafolla, Attilio; McKee, Vickie; Gathergood, Nicholas; Kellett, Andrew

    2017-01-01

    Herein we report the synthesis of tripodal C3-symmetric opioid scaffolds as high-affinity condensation agents of duplex DNA. Condensation was achieved on both supercoiled and canonical B-DNA structures and identified by agarose electrophoresis, viscosity, turbidity and atomic force microscopy (AFM) measurements. Structurally, the requirement of a tris-opioid scaffold for condensation is demonstrated as both di- (C2-symmetric) and mono-substituted (C1-symmetric) mesitylene-linked opioid derivatives poorly coordinate dsDNA. Condensation, observed by toroidal and globule AFM aggregation, arises from surface-binding ionic interactions between protonated, cationic, tertiary amine groups on the opioid skeleton and the phosphate nucleic acid backbone. Indeed, by converting the 6-hydroxyl group of C3-morphine (MC3) to methoxy substituents in C3-heterocodeine (HC3) and C3-oripavine (OC3) molecules, dsDNA compaction is retained thus negating the possibility of phosphate—hydroxyl surface-binding. Tripodal opioid condensation was identified as pH dependent and strongly influenced by ionic strength with further evidence of cationic amine-phosphate backbone coordination arising from thermal melting analysis and circular dichroism spectroscopy, with compaction also witnessed on synthetic dsDNA co-polymers poly[d(A-T)2] and poly[d(G-C)2]. On-chip microfluidic analysis of DNA condensed by C3-agents provided concentration-dependent protection (inhibition) to site-selective excision by type II restriction enzymes: BamHI, HindIII, SalI and EcoRI, but not to the endonuclease DNase I. PMID:27899572

  1. Laser-induced fluorescence studies of excited Sr reactions: II. Sr(3P1)+CH3F, C2H5F, C2H4F2

    NASA Astrophysics Data System (ADS)

    Teule, J. M.; Janssen, M. H. M.; Bulthuis, J.; Stolte, S.

    1999-06-01

    The vibrational and rotational energy distributions of ground state SrF(X 2Σ) formed in the reactions of electronically excited Sr(3P1) with methylfluoride, ethylfluoride, and 1,1-difluoroethane have been studied by laser-induced fluorescence. Although the reactions of ground state Sr with these reactants are exothermic, no SrF products are observed for those reactions in this study. The fraction of available energy disposed into the sum of rotational and vibrational energy of the SrF(X 2Σ) product is approximately the same for all three reactions, i.e., 40%. The reaction of Sr(3P1) with CH3F results in very low vibrational excitation in the SrF reaction product. The product vibration increases in going to C2H5F and C2H4F2. It is concluded that the alkyl group influences the energy disposal mechanism in these reactions, and some suggestions are given for a partial explanation of the observations.

  2. Concentration of 129I in aquatic biota collected from a lake adjacent to the spent nuclear fuel reprocessing plant in Rokkasho, Japan.

    PubMed

    Ueda, Shinji; Kakiuchi, Hideki; Hasegawa, Hidenao; Kawamura, Hidehisa; Hisamatsu, Shun'ichi

    2015-11-01

    The spent nuclear fuel reprocessing plant in Rokkasho, Japan, has been undergoing final testing since March 2006. During April 2006-October 2008, that spent fuel was cut and chemically processed, the plant discharged (129)I into the atmosphere and coastal waters. To study (129)I behaviour in brackish Lake Obuchi, which is adjacent to the plant, (129)I concentrations in aquatic biota were measured by accelerator mass spectrometry. Owing to (129)I discharge from the plant, the (129)I concentration in the biota started to rise from the background concentration in 2006 and was high during 2007-08. The (129)I concentration has been rapidly decreasing after the fuel cutting and chemically processing were finished. The (129)I concentration factors in the biota were higher than those reported by IAEA for marine organisms and similar to those reported for freshwater biota. The estimated annual committed effective dose due to ingestion of foods with the maximum (129)I concentration in the biota samples was 2.8 nSv y(-1). © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Growth and characterizaton of 3C-SiC and 6H-SiC films on 6H-SiC wafers

    NASA Technical Reports Server (NTRS)

    Powell, J. A.; Petit, J. B.; Matus, L. G.; Lempner, S. E.

    1992-01-01

    Single crystal SiC films were grown by CVD on vicinal (0001) SiC wafers cut from boules produced by the modified sublimation method. Wafers with tilt angles less than 0.5 deg yielded 3C-SiC; tilt angles of 3 to 4 deg resulted in 6H-SiC films. The surface morphology of these films, up to 24 microns thick, were investigated as a function of growth parameters such as the Si/C ratio in the input gases and the presence of dopant materials such as nitrogen and trimethylaluminum.

  4. Mapping the Complement Factor H-Related Protein 1 (CFHR1):C3b/C3d Interactions

    PubMed Central

    Laskowski, Jennifer; Thurman, Joshua M.; Hageman, Gregory S.; Holers, V. Michael

    2016-01-01

    Complement factor H-related protein 1 (CFHR1) is a complement regulator which has been reported to regulate complement by blocking C5 convertase activity and interfering with C5b surface association. CFHR1 also competes with complement factor H (CFH) for binding to C3b, and may act as an antagonist of CFH-directed regulation on cell surfaces. We have employed site-directed mutagenesis in conjunction with ELISA-based and functional assays to isolate the binding interaction that CFHR1 undertakes with complement components C3b and C3d to a single shared interface. The C3b/C3d:CFHR1 interface is identical to that which occurs between the two C-terminal domains (SCR19-20) of CFH and C3b. Moreover, we have been able to corroborate that dimerization of CFHR1 is necessary for this molecule to bind effectively to C3b and C3d, or compete with CFH. Finally, we have established that CFHR1 competes with complement factor H-like protein 1 (CFHL-1) for binding to C3b. CFHL-1 is a CFH gene splice variant, which is almost identical to the N-terminal 7 domains of CFH (SCR1-7). CFHR1, therefore, not only competes with the C-terminus of CFH for binding to C3b, but also sterically blocks the interaction that the N-terminus of CFH undertakes with C3b, and which is required for CFH-regulation. PMID:27814381

  5. Rhodium(III)-Catalyzed Amidation of Unactivated C(sp(3) )-H Bonds.

    PubMed

    Wang, He; Tang, Guodong; Li, Xingwei

    2015-10-26

    Nitrogenation by direct functionalization of C-H bonds represents an important strategy for constructing C-N bonds. Rhodium(III)-catalyzed direct amidation of unactivated C(sp(3) )-H bonds is rare, especially under mild reaction conditions. Herein, a broad scope of C(sp(3) )-H bonds are amidated under rhodium catalysis in high efficiency using 3-substituted 1,4,2-dioxazol-5-ones as the amide source. The protocol broadens the scope of rhodium(III)-catalyzed C(sp(3) )-H activation chemistry, and is applicable to the late-stage functionalization of natural products. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. NCI calculations for understanding a physical phase transition in (C6H14N2)[Mn(H2O)6](SeO4)2

    NASA Astrophysics Data System (ADS)

    Naïli, Houcine; François, Michel; Norquist, Alexander J.; Rekik, Walid

    2017-12-01

    An organically templated manganese selenate, (C6H14N2)[Mn(H2O)6](SeO4)2, has been synthesized by slow evaporation and crystallographically characterized. The title compound crystallizes at room temperature in the monoclinic centrosymmetric space group P21/n, with the following unit cell parameters: a = 7.2373(4) Å; b = 12.5600(7) Å; c = 10.1945(7) Å; β = 91.155(4)°, V = 926.50(10) Å3and Z = 2. Its crystal structure is built of manganese(II) cations coordinated by six water molecules in octahedral geometry, disordered dabcodiium cations and selenate anions, resulting in an extensive hydrogen-bonding network. Differential scanning calorimetry (DSC) measurement indicated that the precursor undergoes a reversible phase transition at about 216 and 218 K during the cooling and heating processes respectively. Below this temperature the title compound is noncentrosymmetric with space group P21 and lattice parameters a = 7.2033(8) Å; b = 12.4981(13) Å; c = 10.0888(11) Å; β = 91.281(2)°, V = 908.04(17) Å3 and Z = 2. The disorder-order transformation of the C atoms of (C6H14N2)2+ cation may drive the structural phase transition. The low temperature phase obtained by breaking symmetry presents a fully ordered structure. The noncovalent interaction (NCI) method was used not only to locate, quantify, and visualize intermolecular interactions in the high and low temperature phases but also to confirm the phase transition detected by DSC measurement. The thermal decomposition of this new compound proceeds through four stages giving rise to the manganese oxide as final product at 850 °C.

  7. Characterization of high affinity (/sup 3/H)triazolam binding in rat brain

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

    Earle, M.; Concas, A.; Yamamura, H.I.

    1986-03-01

    The hypnotic Triazolam (TZ), a triazolo (1,4)-benzodiazepine, displays a short physiological half life and has been used for the treatment of insomnia related to anxiety states. Specific binding properties of this recently tritiated TZ were characterized. The authors major objectives were the direct measurement of the temperature dependence and the GABA effect on (/sup 3/H)TZ binding. Saturation studies showed a shift to lower affinity at 37/sup 0/C (K/sub d/ = 0.25 +/- 0.01 nM at O/sup 0/C; K/sub d/ = 1.46 +/- 0.03 nM at 37/sup 0/C) while the B/sub max/ values remained unchanged (1003 +/- 37 fmoles/mg prot. atmore » 0/sup 0/C and 1001 +/- 43 fmoles/mg prot. at 37/sup 0/C). Inhibition studies showed that (/sup 3/H)TZ binding displayed no GABA shift at 0/sup 0/C(K/sub i/ 0.37 +/- 0.03 nM/- GABA and K/sub i/ = 0.55 +/- 0.13 nM/+GABA) but a nearly two-fold shift was apparent at 37/sup 0/C (K/sub i/ = 2.92 +/- 0.2 nM/-GABA; K/sub i/ = 1.37 +/- 0.11 mM/+GABA). These results were also confirmed by saturation studies in the presence or absence of GABA showing a shift to higher affinity in the presence of GABA only at 37/sup 0/C. In Ro 15-1788/(/sup 3/H)TZ competition experiments the presence of GABA did not affect the inhibitory potency of Ro 15-1788 on (/sup 3/H)TZ binding at both temperatures. In conclusion (/sup 3/H)TZ binding showed an extremely high affinity for benzodiazepine receptors. In contrast to reported literature, the findings suggest that TZ interacts with benzodiazepine receptors similar to other benzodiazepine agonists.« less

  8. Analysis of 129I in the soils of Fukushima Prefecture: preliminary reconstruction of 131I deposition related to the accident at Fukushima Daiichi Nuclear Power Plant (FDNPP).

    PubMed

    Muramatsu, Yasuyuki; Matsuzaki, Hiroyuki; Toyama, Chiaki; Ohno, Takeshi

    2015-01-01

    Iodine-131 is one of the most critical radionuclides to be monitored after release from reactor accidents due to the tendency for this nuclide to accumulate in the human thyroid gland. However, there are not enough data related to the reactor accident in Fukushima, Japan to provide regional information on the deposition of this short-lived nuclide (half-life = 8.02 d). In this study we have focused on the long-lived iodine isotope, (129)I (half-life of 1.57 × 10(7) y), and analyzed it by accelerator mass spectrometry (AMS) for surface soil samples collected at various locations in Fukushima Prefecture. In order to obtain information on the (131)I/(129)I ratio released from the accident, we have determined (129)I concentrations in 82 soil samples in which (131)I concentrations were previously determined. There was a strong correlation (R(2) = 0.84) between the two nuclides, suggesting that the (131)I levels in soil samples following the accident can be estimated through the analysis of (129)I. We have also examined the possible influence from (129m)Te on (129)I, and found no significant effect. In order to construct a deposition map of (131)I, we determined the (129)I concentrations (Bq/kg) in 388 soil samples collected from different locations in Fukushima Prefecture and the deposition densities (Bq/m(2)) of (131)I were reconstructed from the results. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. Blending Non-Group-3 Transition Metal and Rare-Earth Metal into a C80 Fullerene Cage with D5h Symmetry.

    PubMed

    Wei, Tao; Jin, Fei; Guan, Runnan; Huang, Jing; Chen, Muqing; Li, Qunxiang; Yang, Shangfeng

    2018-02-11

    Rare-earth metals have been mostly entrapped into fullerene cages to form endohedral clusterfullerenes, whereas non-Group-3 transition metals that can form clusterfullerenes are limited to titanium (Ti) and vanadium (V), and both are exclusively entrapped within an I h -C 80 cage. Non-Group-3 transition-metal-containing endohedral fullerenes based on a C 80 cage with D 5h symmetry, V x Sc 3-x N@D 5h -C 80 (x=1, 2), have now been synthesized, which exhibit two variable cluster compositions. The molecular structure of VSc 2 N@D 5h -C 80 was unambiguously determined by X-ray crystallography. According to a comparative study with the reported Ti- and V-containing clusterfullerenes based on a I h -C 80 cage and the analogous D 5h -C 80 -based metal nitride clusterfullerenes containing rare-earth metals only, the decisive role of the non-Group-3 transition metal on the formation of the corresponding D 5h -C 80 -based clusterfullerenes is unraveled. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Electrical properties of epitaxial 3C- and 6H-SiC p-n junction diodes produced side-by-side on 6H-SiC substrates

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Larkin, David J.; Starr, Jonathan E.; Powell, J. Anthony; Salupo, Carl S.; Matus, Lawrence G.

    1994-01-01

    3C-SiC (beta-SiC) and 6H-SiC p-n junction diodes have been fabricated in regions of both 3C-SiC and 6H-SiC epitaxial layers which were grown side-by-side on low-tilt-angle 6H-SiC substrates via a chemical vapor deposition (CVD) process. Several runs of diodes exhibiting state-of-the-art electrical characteristics were produced, and performance characteristics were measured and compared as a function of doping, temperature, and polytype. The first 3C-SiC diodes which rectify to reverse voltages in excess of 300 V were characterized, representing a six-fold blocking voltage improvement over experimental 3C-SiC diodes produced by previous techniques. When placed under sufficient forward bias, the 3C-SiC diodes emit significantly bright green-yellow light while the 6H-SiC diodes emit in the blue-violet. The 6H-SiC p-n junction diodes represent the first reported high-quality 6H-SiC devices to be grown by CVD on very low-tilt-angle (less than 0.5 deg off the (0001) silicon face) 6H substrates. The reverse leakage current of a 200 micron diameter circular device at 1100 V reverse bias was less than 20 nA at room temperature, and excellent rectification characteristics were demonstrated at the peak characterization temperature of 400 C.

  11. {sup 1}H NMR relaxometry and quadrupole relaxation enhancement as a sensitive probe of dynamical properties of solids—[C(NH{sub 2}){sub 3}]{sub 3}Bi{sub 2}I{sub 9} as an example

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

    Florek-Wojciechowska, M.; Wojciechowski, M.; Brym, Sz.

    {sup 1}H nuclear magnetic resonance relaxometry has been applied to reveal information on dynamics and structure of Gu{sub 3}Bi{sub 2}I{sub 9} ([Gu = C(NH{sub 2}){sub 3}] denotes guanidinium cation). The data have been analyzed in terms of a theory of quadrupole relaxation enhancement, which has been extended here by including effects associated with quadrupole ({sup 14}N) spin relaxation caused by a fast fluctuating component of the electric field gradient tensor. Two motional processes have been identified: a slow one occurring on a timescale of about 8 × 10{sup −6} s which has turned out to be (almost) temperature independent, andmore » a fast process in the range of 10{sup −9} s. From the {sup 1}H-{sup 14}N relaxation contribution (that shows “quadrupole peaks”) the quadrupole parameters, which are a fingerprint of the arrangement of the anionic network, have been determined. It has been demonstrated that the magnitude of the quadrupole coupling considerably changes with temperature and the changes are not caused by phase transitions. At the same time, it has been shown that there is no evidence of abrupt changes in the cationic dynamics and the anionic substructure upon the phase transitions.« less

  12. A Fungal P450 (CYP5136A3) Capable of Oxidizing Polycyclic Aromatic Hydrocarbons and Endocrine Disrupting Alkylphenols: Role of Trp129 and Leu324

    PubMed Central

    Syed, Khajamohiddin; Porollo, Aleksey; Lam, Ying Wai; Yadav, Jagjit S.

    2011-01-01

    The model white rot fungus Phanerochaete chrysosporium, which is known for its versatile pollutant-biodegradation ability, possesses an extraordinarily large repertoire of P450 monooxygenases in its genome. However, the majority of these P450s have hitherto unknown function. Our initial studies using a genome-wide gene induction strategy revealed multiple P450s responsive to individual classes of xenobiotics. Here we report functional characterization of a cytochrome P450 monooxygenase, CYP5136A3 that showed common responsiveness and catalytic versatility towards endocrine-disrupting alkylphenols (APs) and mutagenic/carcinogenic polycyclic aromatic hydrocarbons (PAHs). Using recombinant CYP5136A3, we demonstrated its oxidation activity towards APs with varying alkyl side-chain length (C3-C9), in addition to PAHs (3–4 ring size). AP oxidation involves hydroxylation at the terminal carbon of the alkyl side-chain (ω-oxidation). Structure-activity analysis based on a 3D model indicated a potential role of Trp129 and Leu324 in the oxidation mechanism of CYP5136A3. Replacing Trp129 with Leu (W129L) and Phe (W129F) significantly diminished oxidation of both PAHs and APs. The W129L mutation caused greater reduction in phenanthrene oxidation (80%) as compared to W129F which caused greater reduction in pyrene oxidation (88%). Almost complete loss of oxidation of C3-C8 APs (83–90%) was observed for the W129L mutation as compared to W129F (28–41%). However, the two mutations showed a comparable loss (60–67%) in C9-AP oxidation. Replacement of Leu324 with Gly (L324G) caused 42% and 54% decrease in oxidation activity towards phenanthrene and pyrene, respectively. This mutation also caused loss of activity towards C3-C8 APs (20–58%), and complete loss of activity toward nonylphenol (C9-AP). Collectively, the results suggest that Trp129 and Leu324 are critical in substrate recognition and/or regio-selective oxidation of PAHs and APs. To our knowledge, this is the first

  13. Characterization of a n+3C/n−4H SiC heterojunction diode

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

    Minamisawa, R. A.; Mihaila, A.; Farkas, I.

    We report on the fabrication of n + 3C/n-4H SiC heterojunction diodes (HJDs) potentially promising the ultimate thermal stability of the junction. The diodes were systematically analyzed by TEM, X-ray diffraction, AFM, and secondary ion mass spectroscopy, indicating the formation of epitaxial 3C-SiC crystal on top of 4H-SiC substrate with continuous interface, low surface roughness, and up to ∼7 × 10{sup 17 }cm{sup −3} dopant impurity concentration. The conduction band off-set is about 1 V as extracted from CV measurements, while the valence bands of both SiC polytypes are aligned. The HJDs feature opening voltage of 1.65 V, consistent with the barrier height of about 1.5 eV extractedmore » from CV measurement. We finally compare the electrical results of the n + 3C/n-4H SiC heterojunction diodes with those featuring Si and Ge doped anodes in order to evaluate current challenges involved in the fabrication of such devices.« less

  14. Laboratory detection of the C3N an C4H free radicals

    NASA Technical Reports Server (NTRS)

    Gottlieb, C. A.; Gottlieb, E. W.; Thaddeus, P.; Kawamura, H.

    1983-01-01

    The millimeter-wave spectra of the linear carbon chain free radicals C3N and C4H, first identified in IRC + 10216 and hitherto observed only in a few astronomical sources, have been detected with a Zeeman-modulated spectrometer in laboratory glow discharges through low pressure flowing mixtures of N2 + HC3N and He + HCCH, respectively. Four successive rotational transitions between 168 and 198 GHz have been measured for C3N, and five rotational transitions between 143 and 200 GHz for C4H; each is a well-resolved spin doublet owing to the unpaired electron present in both species. Precise values for the rotational, centrifugal distortion, and spin doubling constants have been obtained, which, with hyperfine constants derived from observations of the lower rotational transitions in the astronomical source TMC 1, allow all the rotational transitions of C3N and C4H at frequencies less than 300 GHz to be calculated to an absolute accuracy exceeding 1 ppm.

  15. Interconversion of η3-H2SiRR' σ-complexes and 16-electron silylene complexes via reversible H-H or C-H elimination.

    PubMed

    Lipke, Mark C; Neumeyer, Felix; Tilley, T Don

    2014-04-23

    Solid samples of η(3)-silane complexes [PhBP(Ph)3]RuH(η(3)-H2SiRR') (R,R' = Et2, 1a; PhMe, 1b; Ph2, 1c, MeMes, 1d) decompose when exposed to dynamic vacuum. Gas-phase H2/D2 exchange between isolated, solid samples of 1c-d3 and 1c indicate that a reversible elimination of H2 is the first step in the irreversible decomposition. An efficient solution-phase trap for hydrogen, the 16-electron ruthenium benzyl complex [PhBP(Ph)3]Ru[η(3)-CH2(3,5-Me2C6H3)] (3) reacts quantitatively with H2 in benzene via elimination of mesitylene to form the η(5)-cyclohexadienyl complex [PhBP(Ph)3]Ru(η(5)-C6H7) (4). This H2 trapping reaction was utilized to drive forward and quantify the elimination of H2 from 1b,d in solution, which resulted in the decomposition of 1b,d to form 4 and several organosilicon products that could not be identified. Reaction of {[PhBP(Ph)3]Ru(μ-Cl)}2 (2) with (THF)2Li(SiHMes2) forms a new η(3)-H2Si species [PhBP(Ph)3]Ru[CH2(2-(η(3)-H2SiMes)-3,5-Me2C6H2)] (5) which reacts with H2 to form the η(3)-H2SiMes2 complex [PhBP(Ph)3]RuH(η(3)-H2SiMes2) (1e). Complex 1e was identified by NMR spectroscopy prior to its decomposition by elimination of Mes2SiH2 to form 4. DFT calculations indicate that an isomer of 5, the 16-electron silylene complex [PhBP(Ph)3]Ru(μ-H)(═SiMes2), is only 2 kcal/mol higher in energy than 5. Treatment of 5 with XylNC (Xyl = 2,6-dimethylphenyl) resulted in trapping of [PhBP(Ph)3]Ru(μ-H)(═SiMes2) to form the 18-electron silylene complex [PhBP(Ph)3]Ru(CNXyl)(μ-H)(═SiMes2) (6). A closely related germylene complex [PhBP(Ph)3]Ru[CN(2,6-diphenyl-4-MeC6H2)](H)(═GeH(t)Bu) (8) was prepared from reaction of (t)BuGeH3 with the benzyl complex [PhBP(Ph)3]Ru[CN(2,6-diphenyl-4-MeC6H2)][η(1)-CH2(3,5-Me2C6H3)] (7). Single crystal XRD analysis indicated that unlike for 6, the hydride ligand in 8 is a terminal hydride that does not engage in 3c-2e Ru-H → Ge bonding. Complex 1b is an effective precatalyst for the catalytic Ge-H dehydrocoupling

  16. Synthesis, NMR conformational analysis and pharmacological evaluation of 7,7a,13,14-tetrahydro-6H-cyclobuta[b]pyrimido[1,2-a:3,4-a']diindole analogues as melatonin receptor ligands.

    PubMed

    Attia, Mohamed I; Güclü, Deniz; Hertlein, Barbara; Julius, Justin; Witt-Enderby, Paula A; Zlotos, Darius P

    2007-07-07

    A structure for the self-condensation product of 2-(1H-indol-2-yl)ethyl tosylate 2a, previously proposed as 6,7,14,15-tetrahydro-15aH-azocino[1,2-a:6,5-b]diindole 3a, was revised based on the (13)C-2D-INADEQUATE experiment, and proved to be 7,7a,13,14-tetrahydro-6H-cyclobuta[b]pyrimido[1,2-a:3,4-a']diindole 4a. A mechanism for the unexpected formation of this novel hexacyclic heterocycle was proposed and its NMR solution structure was elucidated. Five derivatives of the title ring skeleton 12-16 designed as melatonin receptor ligands were synthesized and their affinities for the human MT(1) and MT(2) receptors were determined. Both butyramides 13 and 15, as well as the non-methoxy acetamide 12 exhibited micromolar binding affinities for both receptors being slightly MT(2) selective. The methoxy acetamide 14 showed the best pharmacological profile exhibiting a five times higher affinity for MT(1) (K(i) = 49 nM) than for MT(2) (K(i) = 246 nM) receptor.

  17. 14 CFR Appendix H to Part 121 - Advanced Simulation

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Advanced Simulation H Appendix H to Part... Simulation This appendix provides guidelines and a means for achieving flightcrew training in advanced... simulator, as appropriate. Advanced Simulation Training Program For an operator to conduct Level C or D...

  18. 14 CFR Appendix H to Part 121 - Advanced Simulation

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 14 Aeronautics and Space 3 2012-01-01 2012-01-01 false Advanced Simulation H Appendix H to Part... Simulation This appendix provides guidelines and a means for achieving flightcrew training in advanced... simulator, as appropriate. Advanced Simulation Training Program For an operator to conduct Level C or D...

  19. 14 CFR Appendix H to Part 121 - Advanced Simulation

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 14 Aeronautics and Space 3 2013-01-01 2013-01-01 false Advanced Simulation H Appendix H to Part... Simulation This appendix provides guidelines and a means for achieving flightcrew training in advanced... simulator, as appropriate. Advanced Simulation Training Program For an operator to conduct Level C or D...

  20. Growth and development of Gymnophalloides seoi in immunocompetent and immunosuppressed C3H/HeN mice

    PubMed Central

    Chung, Won-Jae; Kook, Jina; Seo, Min; Park, Yun-Kyu; Guk, Sang-Mee; Choi, Min-Ho; Lee, Soon-Hyung

    1999-01-01

    The growth and development of Gymnophalloides seoi were studied in C3H/HeN mice and effects of immunosuppression of the host on the worm development were observed. Two hundred metacercariae of G. seoi were orally administered to each mouse, and worms were recovered on days 1, 3, 5, 7, 14 and 21 post-infection (PI). The worm recovery rate was significantly higher in immunosuppressed (ImSP) mice than in immunocompetent (ImCT) mice except on days 1 and 3 PI. The worms attained sexual maturity by day 3 PI with eggs in the uterus, and worm dimensions and the number of uterine eggs continuously increased until day 14 PI in ImSP mice. Worms recovered from ImSP mice were significantly larger in size than those from ImCT mice on days 1 and 3 PI, and the number of uterine eggs was significantly larger in ImSP mice on days 5 and 7 PI. Genital organs such as the ovary, testes, and vitellaria, that were already developed in the metacercarial stage, grew a little in size until day 14 PI. The results show that the C3H/HeN mouse is, though not excellent, a suitable laboratory host for G. seoi. PMID:10188379

  1. Step Free Surface Heteroepitaxy of 3C-SiC Layers on Patterned 4H/6H-SiC Mesas and Cantilevers

    NASA Technical Reports Server (NTRS)

    Neudeck, P. G.; Powell, J. A.; Trunek, A. J.; Spry, D. J.

    2004-01-01

    The off-axis approach to SiC epitaxial growth has not prevented many substrate crystal defects from propagating into SiC epilayers, and does not permit the realization of SiC heteropolytype devices. This paper reviews recent advancements in SiC epitaxial growth that begin to overcome the above shortcomings for arrays of device-sized mesas patterned into on-axis 4H/6HSiC wafers. These on-axis mesa growth techniques have produced 4H/6H-SiC homoepilayers and 3C-SiC heteroepilayers with substantially lower dislocation densities. The results should enable improved homojunction and heterojunction silicon carbide prototype devices.

  2. Biogeochemical Considerations Related To The Remediation Of I-129 Plumes

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

    Kaplan, D. I.; Yeager, C.; Denham, M. E.

    2012-09-24

    The objectives of this report were to: provide a current state of the science of radioiodine biogeochemistry relevant to its fate and transport at the Hanford Site; conduct a review of Hanford Site data dealing with groundwater {sup 129}I; and identify critical knowledge gaps necessary for successful selection, implementation, and technical defensibility in support of remediation decisions.

  3. Probing the kinetic energy-release dynamics of H-atom products from the gas-phase reaction of O(3P) with vinyl radical C2H3.

    PubMed

    Jang, Su-Chan; Choi, Jong-Ho

    2014-11-21

    The gas-phase radical-radical reaction dynamics of ground-state atomic oxygen O((3)P) with vinyl radicals C2H3 has been studied by combining the results of vacuum-ultraviolet laser-induced fluorescence spectroscopy in a crossed beam configuration with ab initio calculations. The two radical reactants O((3)P) and C2H3 were produced by photolysis of NO2 and supersonic flash pyrolysis of C2H3I, respectively. Doppler profile analysis of the kinetic energy release of the nascent H-atom products from the title reaction O((3)P) + C2H3H((2)S) + CH2CO (ketene) revealed that the average translational energy of the products and the average fraction of the total available energy were 7.03 ± 0.30 kcal mol(-1) and 7.2%. The empirical data combined with CBS-QB3 level ab initio theory and statistical calculations demonstrated that the title oxygen-hydrogen exchange reaction is a major reaction channel, through an addition-elimination mechanism involving the formation of a short-lived, dynamical complex on the doublet potential energy surface. On the basis of systematic comparison with several exchange reactions of hydrocarbon radicals, the observed kinetic energy release can be explained in terms of the weak impulse at the moment of decomposition in the loose transition state with a product-like geometry and a small reverse barrier along the exit channel.

  4. C 3-symmetric opioid scaffolds are pH-responsive DNA condensation agents.

    PubMed

    McStay, Natasha; Molphy, Zara; Coughlan, Alan; Cafolla, Attilio; McKee, Vickie; Gathergood, Nicholas; Kellett, Andrew

    2017-01-25

    Herein we report the synthesis of tripodal C 3 -symmetric opioid scaffolds as high-affinity condensation agents of duplex DNA. Condensation was achieved on both supercoiled and canonical B-DNA structures and identified by agarose electrophoresis, viscosity, turbidity and atomic force microscopy (AFM) measurements. Structurally, the requirement of a tris-opioid scaffold for condensation is demonstrated as both di- (C 2 -symmetric) and mono-substituted (C 1 -symmetric) mesitylene-linked opioid derivatives poorly coordinate dsDNA. Condensation, observed by toroidal and globule AFM aggregation, arises from surface-binding ionic interactions between protonated, cationic, tertiary amine groups on the opioid skeleton and the phosphate nucleic acid backbone. Indeed, by converting the 6-hydroxyl group of C 3 -morphine ( MC3: ) to methoxy substituents in C 3 -heterocodeine ( HC3: ) and C 3 -oripavine ( OC3: ) molecules, dsDNA compaction is retained thus negating the possibility of phosphate-hydroxyl surface-binding. Tripodal opioid condensation was identified as pH dependent and strongly influenced by ionic strength with further evidence of cationic amine-phosphate backbone coordination arising from thermal melting analysis and circular dichroism spectroscopy, with compaction also witnessed on synthetic dsDNA co-polymers poly[d(A-T) 2 ] and poly[d(G-C) 2 ]. On-chip microfluidic analysis of DNA condensed by C 3 -agents provided concentration-dependent protection (inhibition) to site-selective excision by type II restriction enzymes: BamHI, HindIII, SalI and EcoRI, but not to the endonuclease DNase I. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  5. Calculation and synthesis of ZrC by CVD from ZrCl4-C3H6-H2-Ar system with high H2 percentage

    NASA Astrophysics Data System (ADS)

    Zhu, Yan; Cheng, Laifei; Ma, Baisheng; Gao, Shuang; Feng, Wei; Liu, Yongsheng; Zhang, Litong

    2015-03-01

    A thermodynamic calculation about the synthesis of ZrC from the ZrCl4-C3H6-H2-Ar system with high percentage of H2 was performed using the FactSage thermochemical software. According to the calculation, ZrC coating was synthesized on graphite substrates and carbon fibers by a low pressure chemical vapor deposition (LPCVD) process, and growth rate of the ZrC coating as a function of temperature was investigated. The surface diagrams of condensed-phases in this system were expressed as the functions of the deposition temperature, total pressure and reactant ratios of ZrCl4/(ZrCl4 + C3H6), H2/(ZrCl4 + C3H6), and the yield of the products was determined by the diagrams. A smooth and dense ZrC coating could be synthesized under the instruction of the calculated parameters. The morphologies of the ZrC coatings were significantly affected by temperature and gases flux. The deposition temperature is much lower than that from the ZrCl4-CH4-H2-Ar system.

  6. One-Electron Oxidation of [M(P(t) Bu3 )2 ] (M=Pd, Pt): Isolation of Monomeric [Pd(P(t) Bu3 )2 ](+) and Redox-Promoted C-H Bond Cyclometalation.

    PubMed

    Troadec, Thibault; Tan, Sze-Yin; Wedge, Christopher J; Rourke, Jonathan P; Unwin, Patrick R; Chaplin, Adrian B

    2016-03-07

    Oxidation of zero-valent phosphine complexes [M(P(t) Bu3 )2 ] (M=Pd, Pt) has been investigated in 1,2-difluorobenzene solution using cyclic voltammetry and subsequently using the ferrocenium cation as a chemical redox agent. In the case of palladium, a mononuclear paramagnetic Pd(I) derivative was readily isolated from solution and fully characterized (EPR, X-ray crystallography). While in situ electrochemical measurements are consistent with initial one-electron oxidation, the heavier congener undergoes C-H bond cyclometalation and ultimately affords the 14 valence-electron Pt(II) complex [Pt(κ(2) PC -P(t) Bu2 CMe2 CH2 )(P(t) Bu3 )](+) with concomitant formation of [Pt(P(t) Bu3 )2 H](+) . © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  7. Effects of CYP1A2 on disposition of 2,3,7, 8-tetrachlorodibenzo-p-dioxin, 2,3,4,7,8-pentachlorodibenzofuran, and 2,2',4,4',5,5'-hexachlorobiphenyl in CYP1A2 knockout and parental (C57BL/6N and 129/Sv) strains of mice.

    PubMed

    Diliberto, J J; Burgin, D E; Birnbaum, L S

    1999-08-15

    TCDD is the prototype and most potent member of the highly lipophilic polyhalogenated aromatic hydrocarbons (PHAHs), which are persistent and ubiquitous environmental contaminants. In both acute and subchronic animal studies, there is a specific accumulation of TCDD in liver greater than in adipose tissue. The inducible hepatic binding protein responsible for this hepatic sequestration of TCDD and its congeners has been shown by our laboratory to be CYP1A2 (J. J. Diliberto, D. Burgin, and L. S. Birnbaum, 1997, Biochem. Biophys. Res. Commun. 236, 431-433). The present study was conducted using knockout (KO) mice lacking expression of CYP1A2 (CYP1A2-/-) in order to investigate the role of CYP1A2 gene on the disposition of TCDD, 4-PeCDF (a dioxin-like PHAH), and PCB 153 (a nondioxin-like PCB) in KO (CYP1A2-/-) mice and age-matched parental mice strains (C57BL/6N: CYP1A2+/+, Ah(b/b) and 129/Sv: CYP1A2+/+, Ah(d/d)). Mice were dosed (25 microgram [(3)H]TCDD/kg, 300 microgram [(14)C]4-PeCDF/kg, or 35.8 mg [(14)C]PCB 153/kg bw in a corn oil vehicle) orally and terminated after 4 days. Residues of administered compounds in collected tissues and daily excreta were quantitated using (3)H or (14)C activity. Results demonstrated differential effects in disposition for the various treatments within the three genetically different groups of mice. In KO mice, TCDD, 4-PeCDF, and PCB 153 had very little hepatic localization of chemical, and the major depot was adipose tissue. In contrast, parental strains demonstrated hepatic sequestration of TCDD and 4-PeCDF, whereas disposition of PCB 153 in parental strains was similar to that in KO mice. Another difference between KO mice and parental strains was the enhanced urinary excretion of 4-PeCDF. This study demonstrates the importance of CYP1A2 in pharmacokinetic behavior and mechanistic issues for TCDD and related compounds. Copyright 1999 Academic Press.

  8. Deviation from the trans -Effect in Ligand-Exchange Reactions of Zeise’s Ions PtCl 3(C 2H 4) - with Heavier Halides (Br –, I - )

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

    Hou, Gao-Lei; Govind, Niranjan; Xantheas, Sotiris S.

    Four new Zeise’s family ions with mixed-halide ligands, i.e., PtCl nX 3-n(C 2H 4) - (X = Br, I; n = 1, 2), were synthesized via ligand-exchange reactions of KX salts with KPtCl 3(C 2H 4) in aqueous solutions, and were detected in vacuum via electrospray ionization mass spectrometry. Their photoelectron spectra reveal a series of well-resolved spectral peaks with their electron binding energies (EBEs) decreasing with increasing halide size, with I having a much stronger effect than Br, i.e., 4.57 (–Cl 3) > 4.56 (–Cl 2Br) > 4.53 (–ClBr 2) > 4.34 (–Cl 2I) > 4.30 eV (–ClI 2).more » Ab initio electronic structure calculations including spin-orbit coupling (SOC) predict that the cis- and trans-isomers are nearly isoenergetic with the cis-isomer for –Cl 2X, and the trans-isomer for –ClX 2 slightly favored, respectively. Excited-state spectra calculated with time-dependent density functional theory (TDDFT), and their comparison with the observed ones, suggest that for each species, both the cis- and trans-configurations coexist in the experiments and contribute to the observed spectra, a fact that clearly violates the prediction of the widely accepted trans-effect, which suggests that only one isomer would have formed.« less

  9. Total reaction cross sections of electronic state-specified transition metal cations: V + +C2H6, C3H8, and C2H4 at 0.2 eV

    NASA Astrophysics Data System (ADS)

    Sanders, Lary; Hanton, Scott D.; Weisshaar, James C.

    1990-03-01

    We describe a crossed beam experiment which measures total cross sections for reaction of electronic state-specified V+ with small hydrocarbons at well-defined collision energy E=0.2 eV. The V+ state distribution created at each ionizing wavelength is directly measured by angle-integrated photoelectron spectroscopy (preceding paper). Reactant and product ions are collected and analyzed by pulsed time-of-flight mass spectrometry following a reaction time of 6 μs. Tests of the performance of the apparatus are described in detail. Our experiment defines the reactant V+ electronic state distribution and the collision energy much more precisely than previous work. For all three hydrocarbons C2H6, C3H8, and C2H4, H2 elimination products dominate at 0.2 eV. We observe a dramatic dependence of cross section on the V+ electronic term. The second excited term 3d34s(3F) is more reactive than either lower energy quintet term 3d4(5D) or 3d34s(5F) by a factor of ≥270, 80, and ≥6 for the C2H6, C3H8, and C2H4 reactions, respectively. The 3d34s(3F) reaction cross sections at 0.2 eV are 20±11 Å2, 37±19 Å2, and 2.7±1.6 Å2, respectively, compared with Langevin cross sections of ˜80 Å2. For the C2H6 and C3H8 reactions, cross sections are independent of initial spin-orbit level J within the 3F term to the limits of our accuracy. Comparison with earlier work by Armentrout and co-workers shows that electronic excitation to d3s(3F) is far more effective at promoting H2 elimination than addition of the same total kinetic energy to reactants. Electron spin is clearly a key determinant of V+ reactivity with small hydrocarbons. We suggest that triplet V+ reacts much more efficiently than quintet V+ because of its ability to conserve total electron spin along paths to insertion in a C-H bond of the hydrocarbon.

  10. C3I Rapid Prototype Investigation.

    DTIC Science & Technology

    1986-01-01

    feasibility of applying rapid K prototyping techniques to Air Force C3 1 system developments . This report presents the technical progress during the...computer tunctions. The cost to use each in terms of hardware, software, analysis, and needed further developments was assessed. Prototyping approaches were...acquirer, and developer are the ". basis for problems in C3I system developments . These problems destabilize r-. the requirements determination process

  11. 7 CFR 1955.129 - Business brokers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true Business brokers. 1955.129 Section 1955.129 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS... Dispose of Inventory Property § 1955.129 Business brokers. The services of business brokers or business...

  12. Unimolecular reactivity of organotrifluoroborate anions, RBF3- , and their alkali metal cluster ions, M(RBF3 )2- (M = Na, K; R = CH3 , CH3 CH2 , CH3 (CH2 )3 , CH3 (CH2 )5 , c-C3 H5 , C6 H5 , C6 H5 CH2 , CH2 CHCH2 , CH2 CH, C6 H5 CO).

    PubMed

    Bathie, Fiona L B; Bowen, Chris J; Hutton, Craig A; O'Hair, Richard A J

    2018-07-15

    Potassium organotrifluoroborates (RBF 3 K) are important reagents used in organic synthesis. Although mass spectrometry is commonly used to confirm their molecular formulae, the gas-phase fragmentation reactions of organotrifluoroborates and their alkali metal cluster ions have not been previously reported. Negative-ion mode electrospray ionization (ESI) together with collision-induced dissociation (CID) using a triple quadrupole mass spectrometer were used to examine the fragmentation pathways for RBF 3 - (where R = CH 3 , CH 3 CH 2 , CH 3 (CH 2 ) 3 , CH 3 (CH 2 ) 5 , c-C 3 H 5 , C 6 H 5 , C 6 H 5 CH 2 , CH 2 CHCH 2 , CH 2 CH, C 6 H 5 CO) and M(RBF 3 ) 2 - (M = Na, K), while density functional theory (DFT) calculations at the M06/def2-TZVP level were used to examine the structures and energies associated with fragmentation reactions for R = Me and Ph. Upon CID, preferentially elimination of HF occurs for RBF 3 - ions for systems where R = an alkyl anion, whereas R - formation is favoured when R = a stabilized anion. At higher collision energies loss of F - and additional HF losses are sometimes observed. Upon CID of M(RBF 3 ) 2 - , formation of RBF 3 - is the preferred pathway with some fluoride transfer observed only when M = Na. The DFT-calculated relative thermochemistry for competing fragmentation pathways is consistent with the experiments. The main fragmentation pathways of RBF 3 - are HF elimination and/or R - loss. This contrasts with the fragmentation reactions of other organometallate anions, where reductive elimination, beta hydride transfer and bond homolysis are often observed. The presence of fluoride transfer upon CID of Na(RBF 3 ) 2 - but not K(RBF 3 ) 2 - is in agreement with the known fluoride affinities of Na + and K + and can be rationalized by Pearson's HSAB theory. Copyright © 2018 John Wiley & Sons, Ltd.

  13. [x, p] = i{h_bar} ?

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

    Tang, Jau

    1996-03-01

    Heisenberg`s commutation relation for position x and momentum p, and its validity for relativistic harmonic oscillators are examined, using the techniques of Lie algebra and dual-bosonic representation of x, p and the Hamiltonian H. A modification with [x, p] =i{h_bar}({minus_plus} 1 + H/m{sub 0}c{sup 2}) is proposed for a particle and an antiparticle in a harmonic potential. For a 2 {times} 2 matrix representation for x, p and H operators, the quantized eigenenergy E is given by (E - m{sub 0}c{sup 2})/{h_bar}{omega} = 3/2, 5/2, 7/2, ..., where 1/2 is not allowed.

  14. Computational Study on the Unimolecular Decomposition of JP-8 Jet Fuel Surrogates III: Butylbenzene Isomers ( n-, s-, and t-C14H10).

    PubMed

    Belisario-Lara, Daniel; Mebel, Alexander M; Kaiser, Ralf I

    2018-04-26

    Ab initio G3(CCSD,MP2)//B3LYP/6-311G(d,p) calculations of potential energy surfaces have been carried out to unravel the mechanism of the initial stages of pyrolysis of three C 10 H 14 isomers: n-, s-, and t-butylbenzenes. The computed energy and molecular parameters have been utilized in RRKM-master equation calculations to predict temperature- and pressure-dependent rate constants and product branching ratios for the primary unimolecular decomposition of these molecules and for the secondary decomposition of their radical fragments. The results showed that the primary dissociation of n-butylbenzene produces mostly benzyl (C 7 H 7 ) + propyl (C 3 H 7 ) and 1-phenyl-2-ethyl (C 6 H 5 C 2 H 4 ) + ethyl (C 2 H 5 ), with their relative yields strongly dependent on temperature and pressure, together with a minor amount of 1-phenyl-prop-3-yl (C 9 H 11 ) + methyl (CH 3 ). Secondary decomposition reactions that are anticipated to occur on a nanosecond scale under typical combustion conditions split propyl (C 3 H 7 ) into ethylene (C 2 H 4 ) + methyl (CH 3 ), ethyl (C 2 H 5 ) into ethylene (C 2 H 4 ) + hydrogen (H), 1-phenyl-2-ethyl (C 6 H 5 C 2 H 4 ) into mostly styrene (C 8 H 8 ) + hydrogen (H) and to a lesser extent phenyl (C 6 H 5 ) + ethylene (C 2 H 4 ), and 1-phenyl-prop-3-yl (C 9 H 11 ) into predominantly benzyl (C 7 H 7 ) + ethylene (C 2 H 4 ). The primary decomposition of s-butylbenzene is predicted to produce 1-phenyl-1-ethyl (C 6 H 5 CHCH 3 ) + ethyl (C 2 H 5 ) and a minor amount of 1-phenyl-prop-1-yl (C 9 H 11 ) + methyl (CH 3 ), and then 1-phenyl-1-ethyl (C 6 H 5 CHCH 3 ) and 1-phenyl-prop-1-yl (C 9 H 11 ) rapidly dissociate to styrene (C 8 H 8 ) + hydrogen (H) and styrene (C 8 H 8 ) + methyl (CH 3 ), respectively. t-Butylbenzene decomposes nearly exclusively to 2-phenyl-prop-2-yl (C 9 H 11 ) + methyl (CH 3 ), and further, 2-phenyl-prop-2-yl (C 9 H 11 ) rapidly eliminates a hydrogen atom to form 2-phenylpropene (C 9 H 10 ). If hydrogen atoms or other reactive

  15. A novel Cs-(129)Xe atomic spin gyroscope with closed-loop Faraday modulation.

    PubMed

    Fang, Jiancheng; Wan, Shuangai; Qin, Jie; Zhang, Chen; Quan, Wei; Yuan, Heng; Dong, Haifeng

    2013-08-01

    We report a novel Cs-(129)Xe atomic spin gyroscope (ASG) with closed-loop Faraday modulation method. This ASG requires approximately 30 min to start-up and 110 °C to operate. A closed-loop Faraday modulation method for measurement of the optical rotation was used in this ASG. This method uses an additional Faraday modulator to suppress the laser intensity fluctuation and Faraday modulator thermal induced fluctuation. We theoretically and experimentally validate this method in the Cs-(129)Xe ASG and achieved a bias stability of approximately 3.25 °∕h.

  16. Characterization of 3C-SiC Films Grown on 4H- and 6H-SiC Substrate Mesas During Step-Free Surface Heteroepitaxy

    NASA Technical Reports Server (NTRS)

    Neudeck, Philip G.; Powel J. Anthony; Spry, David J.; Trunek, Andrew J.; Huang, Xianrong; Vetter, William M.; Dudley, Michael; Skowronski, Marek; Liu, Jinqiang

    2002-01-01

    This paper reports detailed structural characterization of 3C-SiC heteroepitaxial films grown on 4H- and 6H-SiC mesa surfaces. 3C-SiC heterofilms grown by the "step-free surface heteroepitaxy" process, free of double-positioning boundary (DPB) and stacking-fault (SF) defects, were compared to less-optimized 3C-SiC heterofilms using High Resolution X-ray Diffraction (HRXRD), High Resolution Cross-sectional Transmission Electron Microscopy (HRXTEM), molten potassium hydroxide (KOH) etching, and dry thermal oxidation. The results suggest that step free surface heteroepitaxy enables remarkably benign partial lattice mismatch strain relief during heterofilm growth.

  17. Mercury-Bridged Cobaltacarborane Complexes Containing B-Hg-B Three-Center Bonds. Synthesis and Structure of mu, mu’-((n5-C5R5)Co(CH3)2C2B3H4)Hg, mu-(n(5)-C5R5)Co(CH3)2C2B3H4)HgCl, (R=H, CH3) and Related Compounds.

    DTIC Science & Technology

    1980-11-01

    MERCURY-BRIDGED COBALTACARBORANE COMPLEXES CONTAINING B-HG-B TH--ETC(U) NOV 80 D C FINSTER . R N GRIMES N0 0 0 1 4-75-0305 UNCLASSXFIED TR󈧨 NL ILn...C5R5) Co 3)2C2B3 4 2 5 .- -C5R5 )Co(CH3)2C2B3H4 ]HgCl, (R=H, CH3 ) and Related Compounds, David C./ Finster -- Russell N./Grimes ( Department of Chemistry...Compounds 1 \\David C. Finster And Russell N. Grimes* Abstract. Reactions of the nid~p-cobaltacarborane anions 01CR )(C 3 )C BH and [n (H 1oC ihH~5n 5

  18. Selective sp3 C-H alkylation via polarity-match-based cross-coupling.

    PubMed

    Le, Chip; Liang, Yufan; Evans, Ryan W; Li, Ximing; MacMillan, David W C

    2017-07-06

    The functionalization of carbon-hydrogen (C-H) bonds is one of the most attractive strategies for molecular construction in organic chemistry. The hydrogen atom is considered to be an ideal coupling handle, owing to its relative abundance in organic molecules and its availability for functionalization at almost any stage in a synthetic sequence. Although many C-H functionalization reactions involve C(sp 3 )-C(sp 2 ) coupling, there is a growing demand for C-H alkylation reactions, wherein sp 3 C-H bonds are replaced with sp 3 C-alkyl groups. Here we describe a polarity-match-based selective sp 3 C-H alkylation via the combination of photoredox, nickel and hydrogen-atom transfer catalysis. This methodology simultaneously uses three catalytic cycles to achieve hydridic C-H bond abstraction (enabled by polarity matching), alkyl halide oxidative addition, and reductive elimination to enable alkyl-alkyl fragment coupling. The sp 3 C-H alkylation is highly selective for the α-C-H of amines, ethers and sulphides, which are commonly found in pharmaceutically relevant architectures. This cross-coupling protocol should enable broad synthetic applications in de novo synthesis and late-stage functionalization chemistry.

  19. Selective sp3 C-H alkylation via polarity-match-based cross-coupling

    NASA Astrophysics Data System (ADS)

    Le, Chip; Liang, Yufan; Evans, Ryan W.; Li, Ximing; MacMillan, David W. C.

    2017-07-01

    The functionalization of carbon-hydrogen (C-H) bonds is one of the most attractive strategies for molecular construction in organic chemistry. The hydrogen atom is considered to be an ideal coupling handle, owing to its relative abundance in organic molecules and its availability for functionalization at almost any stage in a synthetic sequence. Although many C-H functionalization reactions involve C(sp3)-C(sp2) coupling, there is a growing demand for C-H alkylation reactions, wherein sp3 C-H bonds are replaced with sp3 C-alkyl groups. Here we describe a polarity-match-based selective sp3 C-H alkylation via the combination of photoredox, nickel and hydrogen-atom transfer catalysis. This methodology simultaneously uses three catalytic cycles to achieve hydridic C-H bond abstraction (enabled by polarity matching), alkyl halide oxidative addition, and reductive elimination to enable alkyl-alkyl fragment coupling. The sp3 C-H alkylation is highly selective for the α-C-H of amines, ethers and sulphides, which are commonly found in pharmaceutically relevant architectures. This cross-coupling protocol should enable broad synthetic applications in de novo synthesis and late-stage functionalization chemistry.

  20. Photoaffinity labelling of the cardiac calcium channel. (-)-[3H]azidopine labels a 165 kDa polypeptide, and evidence against a [3H]-1,4-dihydropyridine-isothiocyanate being a calcium-channel-specific affinity ligand.

    PubMed

    Ferry, D R; Goll, A; Glossmann, H

    1987-04-01

    The arylazide 1,4-dihydropyridine (-)-[3H]azidopine binds to a saturable population of sites in guinea-pig heart membranes with a dissociation constant (KD) of 30 +/- 7 pM and a density (Bmax.) of 670 +/- 97 fmol/mg of protein. This high-affinity binding site is assumed to reside on voltage-operated calcium channels because reversible binding is blocked stereoselectively by 1,4-dihydropyridine channel blockers and by the enantiomers of Bay K 8644. A low-affinity (KD 25 +/- 7 nM) high-capacity (Bmax. 21.6 +/- 9 pmol/mg of protein) site does not bind (-)- or (+)-Bay K 8644, but is blocked by high concentrations (greater than 500 nM) of dihydro-2,6-dimethyl-4-(2-isothiocyanatophenyl)-3,5-pyridinedicarboxy lic acid dimethyl ester (1,4-DHP-isothiocyanate) or, e.g., (+/-)-nicardipine. (-)-[3H]Azidopine was photoincorporated covalently into bands of 165 +/- 8, 39 +/- 2 and 35 +/- 3 kDa, as determined by SDS/polyacrylamide-gel electrophoresis. Labelling of the 165 kDa band is protected stereoselectively by 1,4-dihydropyridine enantiomers at low (nM) concentrations and by (-)- and (+)-Bay K 8644, whereas the lower-Mr bands are not. Thus, only the 165 kDa band is the calcium-channel-linked 1,4-dihydropyridine receptor. Photolabelling of the 39 or 35 kDa bands was only blocked by 10 microM-1,4-DHP-isothiocyanate or 50 microM-(+/-)-nicardipine but not by 10 microM-(-)-Bay K 8644. [3H]-1,4-DHP-isothiocyanate binds to guinea-pig heart membranes with a KD of 0.35 nM and dissociates with a k-1 of 0.2 min-1 at 30 degrees C. [3H]-1,4 DHP-isothiocyanate irreversibly labels bands of 39 and 35 kDa which are protected by greater than 10 microM-(+/-)-nicardipine or unlabelled ligand but not by 10 microM-(-)-Bay K 8644. Thus, [3H]-1,4-DHP-isothiocyanate is not an affinity probe for the calcium channel.

  1. High-resolution spectroscopy of Saturn at 3 microns: CH 4, CH 3D, C 2H 2, C 2H 6, PH 3, clouds, and haze

    NASA Astrophysics Data System (ADS)

    Kim, Joo Hyeon; Kim, Sang J.; Geballe, Thomas R.; Kim, Sungsoo S.; Brown, Linda R.

    2006-12-01

    We report observation and analysis of a high-resolution 2.87-3.54 μm spectrum of the southern temperate region of Saturn obtained with NIRSPEC at Keck II. The spectrum reveals absorption and emission lines of five molecular species as well as spectral features of haze particles. The ν+ν band of CH 3D is detected in absorption between 2.87 and 2.92 μm; and we derived from it a mixing ratio approximately consistent with the Infrared Space Observatory result. The ν band of C 2H 2 also is detected in absorption between 2.95 and 3.05 μm; analysis indicates a sudden drop in the C 2H 2 mixing ratio at 15 mbar (130 km above the 1 bar level), probably due to condensation in the low stratosphere. The presence of the ν+ν+ν band of C 2H 6 near 3.07 μm, first reported by Bjoraker et al. [Bjoraker, G.L., Larson, H.P., Fink, U., 1981. Astrophys. J. 248, 856-862], is confirmed, and a C 2H 6 condensation altitude of 10 mbar (140 km) in the low stratosphere is determined. We assign weak emission lines within the 3.3 μm band of CH 4 to the ν band of C 2H 6, and derive a mixing ratio of 9±4×10 for this species. Most of the C 2H 6 3.3 μm line emission arises in the altitude range 460-620 km (at ˜μbar pressure levels), much higher than the 160-370 km range where the 12 μm thermal molecular line emission of this species arises. At 2.87-2.90 μm the major absorber is tropospheric PH 3. The cloud level determined here and at 3.22-3.54 is 390-460 mbar (˜30 km), somewhat higher than found by Kim and Geballe [Kim, S.J., Geballe, T.R., 2005. Icarus 179, 449-458] from analysis of a low resolution spectrum. A broad absorption feature at 2.96 μm, which might be due to NH 3 ice particles in saturnian clouds, is also present. The effect of a haze layer at about 125 km (˜12 mbar level) on the 3.20-3.54 μm spectrum, which was not apparent in the low resolution spectrum, is clearly evident in the high resolution data, and the spectral properties of the haze particles suggest that

  2. P.H.Y.S.I.C.S. Can Be Done!

    ERIC Educational Resources Information Center

    Spangler, Lois

    2004-01-01

    P.H.Y.S.I.C.S. (Physics Headstart Yearlong Science Inquiry at Central School) is a series of inquiry investigations and science activities designed to motivate students and teachers and develop a love of physics in our rural agricultural community. The program?s approach infuses physics into the science curriculum while capitalizing on our…

  3. Electron and positron scattering from CF 3I molecules below 600 eV: a comparison with CF 3H

    NASA Astrophysics Data System (ADS)

    Kawada, Michihito K.; Sueoka, Osamu; Kimura, Mineo

    2000-11-01

    The total cross-sections (TCSs) for electron and positron scattering from CF 3I molecules have been studied experimentally. A theoretical analysis based on the continuum multiple-scattering (CMS) method has been performed to understand the origin of resonances and the elastic cross-sections. The present TCS for electron scattering is found to be larger by about 20% than that of T. Underwood-Lemons, D.C. Winkler, J.A. Tossel, J.H. Moore [J. Chem. Phys. 100 (1994) 9117] although the general shape agrees well in the entire energy studied. The difference in the cross-sections for CF 3I and CF 3H is explained by the sizes and the dipole moments of these molecules.

  4. Solvent-Dependent Delamination, Restacking, and Ferroelectric Behavior in a New Charge-Separated Layered Compound: [NH4 ][Ag3 (C9 H5 NO4 S)2 (C13 H14 N2 )2 ]⋅8 H2 O.

    PubMed

    Sushrutha, Sringeri Ramesh; Mohana, Shivanna; Pal, Somnath; Natarajan, Srinivasan

    2017-01-03

    A new anionic coordination polymer, [NH 4 ][Ag 3 (C 9 H 5 NO 4 S) 2 (C 13 H 14 N 2 ) 2 ]⋅8 H 2 O, with a two-dimensional structure, has been synthesized by a reaction between silver nitrate, 8-hydroxyquinoline-5-sulfonic acid (HQS), and 4,4'-trimethylene dipyridine (TMDP). The compound stabilizes in a noncentrosymmetric space group, and the lattice water molecules and the charge-compensating [NH 4 ] + group occupy the inter-lamellar spaces. The lattice water molecules can be fully removed and reinserted, which is accompanied by a crystalline-amorphous-crystalline transformation. This transformation resembles the collapse/delamination and restacking of the layers. To the best of our knowledge, this is the first observation of delamination and restacking in an inorganic coordination polymer that contains silver. The presence of a natural dipole (the anionic framework and cationic ammonium ions) along with the noncentrosymmetric space group gives rise to the room-temperature ferroelectric behavior of the compound. The ferroelectric behavior is also water-dependent and exhibits a ferroelectric-paraelectric transformation. The temperature-dependent dielectric measurements indicate that the ferroelectric/ paraelectric transformation occurs at 320 K. This transformation has also been investigated by using in-situ IR spectroscopy and PXRD studies. The second-harmonic generation (SHG) study indicated values that are comparable to some of the known SHG solids, such as potassium dihydrogen phosphate (KDP) and urea. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The selective activation of a C-F bond with an auxiliary strong Lewis acid: a method to change the activation preference of C-F and C-H bonds.

    PubMed

    Wang, Lin; Sun, Hongjian; Li, Xiaoyan; Fuhr, Olaf; Fenske, Dieter

    2016-11-15

    The selective activation of the C-F bonds in substituted (2,6-difluorophenyl)phenylimines (2,6-F 2 H 3 C 6 -(C[double bond, length as m-dash]NH)-n'-R-C 6 H 4 (n' = 2, R = H (1); n' = 2, R = Me (2); n' = 4, R = tBu (3))) by Fe(PMe 3 ) 4 with an auxiliary strong Lewis acid (LiBr, LiI, or ZnCl 2 ) was explored. As a result, iron(ii) halides ((H 5 C 6 -(C[double bond, length as m-dash]NH)-2-FH 3 C 6 )FeX(PMe 3 ) 3 (X = Br (8); Cl (9)) and (n-RH 4 C 6 -(C[double bond, length as m-dash]NH)-2'-FH 3 C 6 )FeX(PMe 3 ) 3 (n = 2, R = Me, X = Br (11); n = 4, R = tBu, X = I (12))) were obtained. Under similar reaction conditions, using LiBF 4 instead of LiBr or ZnCl 2 , the reaction of (2,6-difluorophenyl)phenylimine with Fe(PMe 3 ) 4 afforded an ionic complex [(2,6-F 2 H 3 C 6 -(C[double bond, length as m-dash]NH)-H 4 C 6 )Fe(PMe 3 ) 4 ](BF 4 ) (10) via the activation of a C-H bond. The method of C-F bond activation with an auxiliary strong Lewis acid is appropriate for monofluoroarylmethanimines. Without the Lewis acid, iron(ii) hydrides ((2-RH 4 C 6 -(C[double bond, length as m-dash]NH)-2'-FH 3 C 6 )FeH(PMe 3 ) 3 (R = H (13); Me (14))) were generated from the reactions of Fe(PMe 3 ) 4 with the monofluoroarylmethanimines (2-FH 4 C 6 -(C[double bond, length as m-dash]NH)-2'-RC 6 H 4 (R = H (4); Me (5))); however, in the presence of ZnCl 2 or LiBr, iron(ii) halides ((2-RH 4 C 6 -(C[double bond, length as m-dash]NH)-H 4 C 6 )FeX(PMe 3 ) 3 (R = H, X = Cl (15); R = Me, X = Br (16))) could be obtained through the activation of a C-F bond. Furthermore, a C-F bond activation with good regioselectivity in (pentafluorophenyl)arylmethanimines (F 5 C 6 -(C[double bond, length as m-dash]NH)-2,6-Y 2 C 6 H 3 (Y = F (6); H (7))) could be realized in the presence of ZnCl 2 to produce iron(ii) chlorides ((2,6-Y 2 H 3 C 6 -(C[double bond, length as m-dash]NH)-F 4 C 6 )FeCl(PMe 3 ) 3 (Y = F (17); H (18))). This series of iron(ii) halides could be used to catalyze the hydrosilylation reaction of

  6. AMS analyses of I-129 from the Fukushima Daiichi nuclear accident in the Pacific Ocean waters of the Coast La Jolla--San Diego, USA.

    PubMed

    Stan-Sion, C; Enachescu, M; Petre, A R

    2015-05-01

    This paper presents the results of an experimental study we performed by using the Accelerator Mass Spectrometry (AMS) method with iodine 129 (T1/2 = 15.7 My), to determine the increase of the radionuclide content in the USA West Pacific Coast waters, two years after the March 2011 Fukushima Daiichi nuclear power plant accident. The collection of the water samples took place between April and July 2013 at regular intervals of time, from the Pacific Ocean, at the cove of La Jolla, San Diego, USA. The results of the experiments showed a significant increase of the radionuclide concentration during the late spring of 2013. Compared to the isotopic ratio (129)I/(127)I, measured at a 40 km distance, offshore of Fukushima and immediately after the accident, our results show an increase on the USA West Coast that was more than a 2.5 factor higher. Also, compared with the pre-Fukushima background values, our results show an isotopic ratio of about two orders of magnitude higher. A distinct feature of the reconstructed radioactive plume was that it traveled with a speed of 12 cm s(-1), which we estimated and is consistent with the zonal speed in the Pacific. We coupled our (129)I results with the measurements from the June 2011 KOK cruise and we derived the levels of activity for (3)H and (137)Cs. On the USA West Coast, they did not exceed the international regulatory limits.

  7. STS 129 Return Samples: Assessment of Air Quality aboard the Shuttle (STS-129) and International Space Station (ULF3)

    NASA Technical Reports Server (NTRS)

    James, John T.

    2010-01-01

    Reports on the air quality aboard the Space Shuttle (STS-129), and the International Space station (ULF3). NASA analyzed the grab sample canisters (GSCs) and the formaldehyde badges aboard both locations for carbon monoxide levels. The three surrogates: (sup 13)C-acetone, fluorobenzene, and chlorobenzene registered 109, 101, and 109% in the space shuttle and 81, 87, and 55% in the International Space Station (ISS). From these results the atmosphere in both the Space Shuttle and the International Space Station (ISS) was found to be breathable.

  8. 76 FR 63714 - Technical Standard Order (TSO)-C129a, Airborne Supplemental Navigation Equipment Using the Global...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-13

    ..., Airborne Supplemental Navigation Equipment Using the Global Positioning System (GPS) AGENCY: Federal Aviation Administration (FAA), DOT ACTION: Notice of cancellation of TSO-C129a, Airborne Supplemental... cancellation of TSO-C129a, Airborne Supplemental Navigation Equipment Using the Global Positioning System (GPS...

  9. 7 CFR 1956.125-1956.129 - [Reserved

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 14 2010-01-01 2009-01-01 true [Reserved] 1956.125-1956.129 Section 1956.125-1956.129...) PROGRAM REGULATIONS (CONTINUED) DEBT SETTLEMENT Debt Settlement-Community and Business Programs §§ 1956.125-1956.129 [Reserved] ...

  10. Platinum-Catalyzed Terminal-Selective C(sp3)–H Oxidation of Aliphatic Amines

    PubMed Central

    Lee, Melissa; Sanford, Melanie S.

    2016-01-01

    This paper describes the terminal-selective Pt-catalyzed C(sp3)–H oxidation of aliphatic amines without the requirement for directing groups. CuCl2 is employed as a stoichiometric oxidant, and the reactions proceed in high yield at Pt loadings as low as 1 mol %. These transformations are conducted in the presence of sulfuric acid, which reacts with the amine substrates in situ to form ammonium salts. We propose that protonation of the amine serves at least three important roles: (i) it renders the substrates soluble in the aqueous reaction medium; (ii) it limits binding of the amine nitrogen to Pt or Cu; and (ii) it electronically deactivates the C–H bonds proximal to the nitrogen center. We demonstrate that this strategy is effective for the terminal-selective C(sp3)–H oxidation of a variety of primary, secondary and tertiary amines. PMID:26439251

  11. 14 CFR Appendix H to Part 121 - Advanced Simulation

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 14 Aeronautics and Space 3 2014-01-01 2014-01-01 false Advanced Simulation H Appendix H to Part... Simulation Link to an amendment published at 78 FR 67846, Nov. 12, 2013. This appendix provides guidelines... Simulation Training Program For an operator to conduct Level C or D training under this appendix all required...

  12. The Tomato 14-3-3 Protein TFT4 Modulates H+ Efflux, Basipetal Auxin Transport, and the PKS5-J3 Pathway in the Root Growth Response to Alkaline Stress1[C][W

    PubMed Central

    Xu, Weifeng; Jia, Liguo; Shi, Weiming; Baluška, František; Kronzucker, Herbert J.; Liang, Jiansheng; Zhang, Jianhua

    2013-01-01

    Alkaline stress is a common environmental stress, in particular in salinized soils. Plant roots respond to a variety of soil stresses by regulating their growth, but the nature of the regulatory pathways engaged in the alkaline stress response (ASR) is not yet understood. Previous studies show that PIN-FORMED2, an auxin (indole-3-acetic acid [IAA]) efflux transporter, PKS5, a protein kinase, and DNAJ HOMOLOG3 (J3), a chaperone, play key roles in root H+ secretion by regulating plasma membrane (PM) H+-ATPases directly or by targeting 14-3-3 proteins. Here, we investigated the expression of all 14-3-3 gene family members (TOMATO 14-3-3 PROTEIN1 [TFT1]–TFT12) in tomato (Solanum lycopersicum) under ASR, showing the involvement of four of them, TFT1, TFT4, TFT6, and TFT7. When these genes were separately introduced into Arabidopsis (Arabidopsis thaliana) and overexpressed, only the growth of TFT4 overexpressors was significantly enhanced when compared with the wild type under stress. H+ efflux and the activity of PM H+-ATPase were significantly enhanced in the root tips of TFT4 overexpressors. Microarray analysis and pharmacological examination of the overexpressor and mutant plants revealed that overexpression of TFT4 maintains primary root elongation by modulating PM H+-ATPase-mediated H+ efflux and basipetal IAA transport in root tips under alkaline stress. TFT4 further plays important roles in the PKS5-J3 signaling pathway. Our study demonstrates that TFT4 acts as a regulator in the integration of H+ efflux, basipetal IAA transport, and the PKS5-J3 pathway in the ASR of roots and coordinates root apex responses to alkaline stress for the maintenance of primary root elongation. PMID:24134886

  13. Highly improved passivation of c-Si surfaces using a gradient i a-Si:H layer

    NASA Astrophysics Data System (ADS)

    Lee, Soonil; Ahn, Jaehyun; Mathew, Leo; Rao, Rajesh; Zhang, Zhongjian; Kim, Jae Hyun; Banerjee, Sanjay K.; Yu, Edward T.

    2018-04-01

    Surface passivation using intrinsic a-Si:H (i a-Si:H) films plays a key role in high efficiency c-Si heterojunction solar cells. In this study, we demonstrate improved passivation quality using i a-Si:H films with a gradient-layered structure consisting of interfacial, transition, and capping layers deposited on c-Si surfaces. The H2 dilution ratio (R) during deposition was optimized individually for the interfacial and capping layers, which were separated by a transition layer for which R changed gradually between its values for the interfacial and capping layers. This approach yielded a significant reduction in surface carrier recombination, resulting in improvement of the minority carrier lifetime from 1480 μs for mono-layered i a-Si:H passivation to 2550 μs for the gradient-layered passivation approach.

  14. Retrospective reconstruction of Ioidne-131 distribution at the Fukushima Daiichi Nuclear Power Plant accident by analysis of Ioidne-129

    NASA Astrophysics Data System (ADS)

    Matsuzaki, Hiroyuki; Muramatsu, Yasuyuki; Toyama, Chiaki; Ohno, Takeshi; Kusuno, Haruka; Miyake, Yasuto; Honda, Maki

    2014-05-01

    Science and Education on June, 2011. So far more than 500 samples were measured and determined I-129 deposition amount by AMS at MALT (Micro Analysis Laboratory, Tandem accelerator), The University of Tokyo. The measurement error from AMS is less than 5%, typically 3%. The overall uncertainty is estimated less than 30%, including the uncertainty from that of the nominal value of the standard reference material used, that of I-129/I-131 ratio estimation, that of the "representativeness" for the region by the analyzed sample, etc. The isotopic ratio I-129/I-131 from the reactor was estimated [3] (to be 22.3 +- 6.3 as of March 11, 2011) from a series of samples collected by a group of The University of Tokyo on the 20th of April, 2011 for which the I-131 was determined by gamma-ray spectrometry with good precision. Complementarily, we had investigated the depth profile in soil of the accident derived I-129 and migration speed after the deposition and found that more than 90% of I-129 was concentrated within top 5 cm layer and the downward migration speed was less than 1cm/yr [4]. From the set of I-129 data, corresponding I-131 were calculated and the distribution map is going to be constructed. Various fine structures of the distribution came in sight. [1] Y. Nikiforov and D. R. Gnepp, 1994, Cancer, Vol. 47, pp748-766. [2] T. Straume, et al., 1996, Health Physics, Vol. 71, pp733-740. [3] Y. Miyake, H. Matsuzaki et al.,2012, Geochem. J., Vol. 46, pp327-333. [4] M. Honda, H. Matsuzaki et al., under submission.

  15. Exogenous cytokine modulation or neutralization of interleukin-10 enhance survival in lipopolysaccharide-hyporesponsive C3H/HeJ mice with Klebsiella infection

    PubMed Central

    Wang, M-J; Jeng, K-C G; Ping, L-I

    1999-01-01

    Klebsiella pneumoniae has been isolated from liver abscesses in patients with leukaemia or diabetes. The resistance of Klebsiella infection in lipopolysaccharide (LPS)-hyporesponsive mice is unclear. Female C3H/HeJ and C3H/HeN mice, 6–8 weeks old, were intraperitoneally (i.p.) injected with K. pneumoniae. The results showed that C3H/HeJ mice were 24 times more susceptible [lethal dose 50% (LD50) 250 colony-forming units] than C3H/HeN mice to K. pneumoniae infection. C3H/HeJ mice, uninfected or infected with K. pneumoniae, had higher liver interleukin (IL)-10 levels and IL-10 mRNA levels than C3H/HeN mice. Previously, pretreatment with IL-1β and tumour necrosis factor-α (TNF-α) protected C3H/HeJ mice from lethal bacterial infection. Therefore the effects of pretreatment with IL-1β and TNF-α or antimurine IL-10 antibody i.p. 1 hr before this infection in both strains of C3H mice were examined. Pretreatment with TNF-α or anti-IL-10 antibody enhanced the survival of both strains of mice. TNF-α, in combination with IL-1β, enhanced the survival and bacterial clearance better than single pretreatment in C3H/HeJ mice. Anti-IL-10 antibody increased bacterial clearance and significantly reduced liver cytokine mRNA levels in C3H/HeJ mice more than it did in the controls during infection. These results indicate that exogenous cytokine modulation or neutralization of IL-10 enhance the resistance of LD50 infection in C3H/HeJ mice. PMID:10469238

  16. Spectroscopic characterization of C7H3(+) and C7H3˙: electronic absorption and fluorescence in 6 K neon matrices.

    PubMed

    Chakraborty, Arghya; Fulara, Jan; Dietsche, Rainer; Maier, John P

    2014-04-21

    Mass selective deposition of C7H3(+) (m/z = 87) into solid neon reveals the 1(1)A1←X(1)A1 electronic absorption system of hepta-1,2,3,4,5,6-heptahexaenylium cation B(+) [H2CCCCCCCH](+) with an origin band at 441.3 nm, 1(1)A'←X(1)A' transition of 2,4-pentadiynylium,1-ethynyl cation C(+) [HCCCHCCCCH](+) starting at 414.6 nm and the 1(1)A1←X(1)A1 one of cyclopropenylium,1,3-butadiynyl cation A(+) [HCCCCC<(CH=CH)](+) with an onset at 322.2 nm. Vibrationally resolved fluorescence was observed for isomer B(+) upon laser excitation of the absorption bands in the 1(1)A1←X(1)A1 transition. After neutralization of the cations in the matrix five absorption systems of the C7H3 neutral radicals starting at 530.3, 479.4, 482.3, 325.0 and 302.5 nm were detected. These were identified as the 1(2)A'←X(2)A' and 2(2)A'←X(2)A' electronic transitions of 2-(buta-1,3-diynyl)cycloprop-2yl-1-1ylidene E˙ [HCCCCC<(C=CH2)]˙, 1(2)B1←X(2)B1 of 1,2,3,4,5,6-heptahexaenyl B˙ [H2CCCCCCCH]˙, 3(2)B1←X(2)B1 of 3-buta-1,3-diynyl-cyclopropenyl A˙ [HCCCCC<(CH=CH)]˙ and 2(2)B1←X(2)A2 transition of 1,2-divinylidene-cyclopropanyl radical F˙ [HCC-cyc-(CCHC)-CCH]˙, respectively. The assignment is based on calculated vertical excitation energies using the CASPT2 method. Comparison of the calculated harmonic vibrational frequencies with those inferred from the spectra supports the assignment.

  17. Syntheses, structures, and 1H, 13C{ 1H} and 119Sn{ 1H} NMR chemical shifts of a family of trimethyltin alkoxide, amide, halide and cyclopentadienyl compounds

    DOE PAGES

    Lichtscheidl, Alejandro G.; Janicke, Michael T.; Scott, Brian L.; ...

    2015-08-21

    The synthesis and full characterization, including Nuclear Magnetic Resonance (NMR) data ( 1H, 13C{ 1H} and 119Sn{ 1H}), for a series of Me 3SnX (X = O-2,6-tBu 2C 6H 3 (1), (Me 3Sn)N(2,6- iPr 2C 6H 3) (3), NH-2,4,6- tBu 3C 6H 2 (4), N(SiMe 3) 2 (5), NEt 2, C 5Me 5 (6), Cl, Br, I, and SnMe 3) compounds in benzene-d 6, toluene-d 8, dichloromethane-d 2, chloroform-d 1, acetonitrile-d 3, and tetrahydrofuran-d 8 are reported. The X-ray crystal structures of Me 3Sn(O-2,6- tBu 2C 6H 3) (1), Me 3Sn(O-2,6- iPr 2C 6H 3) (2), and (Me 3Sn)(NH-2,4,6- tBumore » 3C 6H 2) (4) are also presented. As a result, these compiled data complement existing literature data and ease the characterization of these compounds by routine NMR experiments.« less

  18. Design and syntheses of hybrid metal-organic materials based on K3[M(C2O4)33H2O [M(III)=Fe, Al, Cr] metallotectons

    NASA Astrophysics Data System (ADS)

    Sun, Yayong; Zong, Yingxia; Ma, Haoran; Zhang, Ao; Liu, Kang; Wang, Debao; Wang, Wenqiang; Wang, Lei

    2016-05-01

    By using K3[M(C2O4)33H2O [M(III)=Fe, Al, Cr] (C2O42-=oxalate) metallotectons as the starting material, we have synthesized eight novel complexes with formulas [{Fe(C2O4)2(H2O)2}2]·(H-L1)2·H2O 1, [Fe(C2O4)Cl2]·(H2-L2)0.5·(L2)0.5·H2O 2, [{Fe(C2O4)1.5Cl2}2]·(H-L3)43, [Fe2(C2O4)Cl8]·(H2-L4)2·2H2O 4, K[Al(C2O4)3]·(H2-L5)·2H2O 5, K[Al(C2O4)3]·(H-L6)2·2H2O 6, K[Cr(C2O4)3]·2H2O 7, Na[Fe(C2O4)3]·(H-L6)2·2H2O 8 (with L1=4-dimethylaminopyridine, L2=2,3,5,6-tetramethylpyrazine, L3=2-aminobenzimidazole, L4=1,4-bis-(1H-imidazol-1-yl)benzene, L5=1,4-bis((2-methylimidazol-1-yl)methyl)benzene, L6=2-methylbenzimidazole). Their structures have been determined by single-crystal X-ray diffraction analyses, elemental analyses, IR spectra and thermogravimetric analyses. Compound 3 is a 2D H-bonded supramolecular architecture. Others are 3D supramolecular structures. Compound 1 shows a [Fe(C2O4)2(H2O)2]- unit and 3D antionic H-bonded framework. Compound 2 features a [Fe(C2O4)Cl2]- anion and 1D iron-oxalate-iron chain. Compound 3 features a [Fe2(C2O4)3Cl4]4- unit. Compound 4 features distinct [Fe2(C2O4)Cl8]4- units, which are mutual linked by water molecules to generated a 2D H-bonded network. Compound 5 features infinite ladder-like chains constructed by [Al(C2O4)3]3- units and K+ cations. The 1D chains are further extended into 3D antionic H-bonded framework through O-H···O H-bonds. Compounds 6-8 show 2D [KAl(C2O4)3]2- layer, [KCr(C2O4)3]2- layer and [NaFe(C2O4)3]2- layer, respectively.

  19. Isochoric thermal conductivity of solid n-alkanes: Hexane C6H14

    NASA Astrophysics Data System (ADS)

    Konstantinov, V. A.; Revyakin, V. P.; Sagan, V. V.

    2011-05-01

    The isochoric thermal conductivity of solid n-hexane C6H14 is studied using three samples with different densities for temperatures ranging from 100 K to the onset of melting. In all cases, the isochoric thermal conductivity varies more weakly than Λ∝1/T. The present results are compared with the thermal conductivities of other representatives of the n-alkanes. The contributions of low-frequency phonons and "diffuse modes" to the thermal conductivity are calculated.

  20. Growth and Characterization of 3C-SiC and 2H-AIN/GaN Films and Devices Produced on Step-Free 4H-SiC Mesa Substrates

    NASA Technical Reports Server (NTRS)

    Neudeck, P. G.; Du, H.; Skowronski, M.; Spry, D. J.; Trunek, A. J.

    2007-01-01

    While previously published experimental results have shown that the step-free (0 0 0 1) 4H-SiC mesa growth surface uniquely enables radical improvement of 3C-SiC and 2H-AlN/GaN heteroepitaxial film quality (greater than 100-fold reduction in extended defect densities), important aspects of the step-free mesa heterofilm growth processes and resulting electronic device benefits remain to be more fully elucidated. This paper reviews and updates recent ongoing studies of 3C-SiC and 2H-AlN/GaN heteroepilayers grown on top of 4H-SiC mesas. For both 3C-SiC and AlN/GaN films nucleated on 4H-SiC mesas rendered completely free of atomic-scale surface steps, TEM studies reveal that relaxation of heterofilm strain arising from in-plane film/substrate lattice constant mismatch occurs in a remarkably benign manner that avoids formation of threading dislocations in the heteroepilayer. In particular, relaxation appears to occur via nucleation and inward lateral glide of near-interfacial dislocation half-loops from the mesa sidewalls. Preliminary studies of homojunction diodes implemented in 3C-SiC and AlN/GaN heterolayers demonstrate improved electrical performance compared with much more defective heterofilms grown on neighbouring stepped 4H-SiC mesas. Recombination-enhanced dislocation motion known to degrade forward-biased 4H-SiC bipolar diodes has been completely absent from our initial studies of 3C-SiC diodes, including diodes implemented on defective 3C-SiC heterolayers grown on stepped 4H-SiC mesas.

  1. Pathways to Oxygen-Bearing Molecules in the Interstellar Medium and in Planetary Atmospheres: Cyclopropenone (c-C3H2O) and Propynal (HCCCHO)

    NASA Astrophysics Data System (ADS)

    Zhou, Li; Kaiser, Ralf I.; Gao, Li Gyun; Chang, Agnes H. H.; Liang, Mao-Chang; Yung, Yuk L.

    2008-10-01

    We investigated the formation of two C3H2O isomers, i.e., cyclopropenone (c-C3H2O) and propynal (HCCCHO), in binary ice mixtures of carbon monoxide (CO) and acetylene (C2H2) at 10 K in an ultrahigh vacuum machine on high-energy electron irradiation. The chemical evolution of the ice samples was followed online and in situ via a Fourier transform infrared spectrometer and a quadrupole mass spectrometer. The temporal profiles of the cyclopropenone and propynal isomers suggest (pseudo-) first-order kinetics. The cyclic structure (c-C3H2O) is formed via an addition of triplet carbon monoxide to ground-state acetylene (or vice versa); propynal (HCCCHO) can be synthesized from a carbon monoxide-acetylene complex via a [HCO...CCH] radical pair inside the matrix cage. These laboratory studies showed for the first time that both C3H2O isomers can be formed in low-temperature ices via nonequilibrium chemistry initiated by energetic electrons as formed in the track of Galactic cosmic ray particles penetrating interstellar icy grains in cold molecular clouds. Our results can explain the hitherto unresolved gas phase abundances of cyclopropenone in star-forming regions via sublimation of c-C3H2O as formed on icy grains in the cold molecular cloud stage. Implications for the heterogeneous oxygen chemistry of Titan and icy terrestrial planets and satellites suggest that the production of oxygen-bearing molecules such as C3H2O may dominate on aerosol particles compared to pure gas phase chemistry.

  2. Thermally-induced first-order phase transition in the (FC6H4C2H4NH3)2[PbI4] photoluminescent organic-inorganic material

    NASA Astrophysics Data System (ADS)

    Koubaa, M.; Dammak, T.; Garrot, D.; Castro, M.; Codjovi, E.; Mlayah, A.; Abid, Y.; Boukheddaden, K.

    2012-03-01

    The thermal properties of the perovskite slab alkylammonium lead iodide (FC6H4C2H4NH3)2[PbI4] are investigated using spectroscopic ellipsometry, differential scanning calorimetry, photoluminescence, and Raman spectroscopy. The spectroscopic ellipsometry, performed in the heating mode, clearly evidenced the presence of a singularity at 375 K. This is corroborated by the temperature dependence of the photoluminescence, which pointed out a first-order order-disorder phase transition at ˜375 K, with a hysteresis loop of 40 K width. Raman spectroscopy data suggest that this transition arises from a dynamic rotational disordering of the ammonium headgroups of the alkylammonium chain. In contrast, differential scanning calorimetry measurements on a pellet sample led to an entropy change value ΔS ≈0.39 J/K/mol at the transition, suggesting the existence of a residual short-range order of the NH3+ on cooling from the high temperature phase.

  3. Preparation of 7-hydroxy-2-oxoindolin-3-ylacetic acid and its [13C2], [5-n-3H], and [5-n-3H]-7-O-glucosyl analogues for use in the study of indol-3-ylacetic acid catabolism

    NASA Technical Reports Server (NTRS)

    Lewer, P.; Bandurski, R. S. (Principal Investigator)

    1987-01-01

    An improved synthesis of 7-hydroxy-2-oxoindolin-3-ylacetic acid via the base-induced condensation reaction between oxalate esters and 7-benzyloxyindolin-2-one is described. 7-Benzyloxyindolin-2-one was prepared in four steps and 50% overall yield from 3-hydroxy-2-nitrotoluene. The yield of the title compound from 7-benzyloxyindolin-2-one was 56%. This route was used to prepare 7-hydroxy-2-oxoindolin-3-yl[13C2]acetic acid in 30% yield from [13C2]oxalic acid dihydrate. The method could not be extended to the preparation of the corresponding [14C2]-compound. However, an enzyme preparation from Zea mays roots catalysed the conversion of carrier-free [5-n-3H]indol-3-ylacetic acid with a specific activity of 16.7 Ci mmol-1 to a mixture of 7-hydroxy-2-oxo[5-n-3H]indolin-3-ylacetic acid and its [5-n-3H]-7-O-glucoside in ca. 3 and 40% radiochemical yield respectively. The glucoside was converted into the 7-hydroxy compound in 80% yield by means of beta-glucosidase.

  4. The Local Pharmacokinetics of 3H-Ropivacaine and 14C-Lidocaine After Maxillary Infiltration Anesthesia in Rats

    PubMed Central

    Kimi, Hiromi; Yamashiro, Mikiko; Hashimoto, Shuichi

    2012-01-01

    The effects of infiltration anesthesia with ropivacaine on the dental pulp are considered to be weak. This may be partly associated with its permeation into the oral tissue. With the objective of investigating the local pharmacokinetics of ropivacaine and lidocaine following infiltration anesthesia, we injected 3H-ropivacaine or 14C-lidocaine to the palatal mucosa in rats, measured distributions of radioactivity in the maxilla, and compared the local pharmacokinetics of these agents. The animals were sacrificed at various times and the maxillas were removed. The palatal mucosa and maxillary nerve were resected, and the bone was divided into 6 portions. We measured radioactivity in each tissue and calculated the level of each local anesthetic (n  =  8). Lidocaine diffused to the surrounding tissue immediately after the injection, whereas ropivacaine tended to remain in the palatal mucosa for a longer period. Lidocaine showed a higher affinity for the maxillary bone than ropivacaine. There was a correlation between the distribution level of local anesthetics in the maxillary bone and that in the maxillary nerve. The lower-level effects of infiltration anesthesia with ropivacaine on the dental pulp may be because ropivacaine has a high affinity for soft tissue, and its transfer to bone is slight. PMID:22822994

  5. Subthreshold parallel pumping experiments on the quasi one-dimensional S = {1}/{2} ferromagnets [C 6H 11NH 3]CuBr 3 and [C 6H 11NH 3]CuCl 3

    NASA Astrophysics Data System (ADS)

    Hoogerbeets, R.; Wiegers, S. A. J.; Van Duyneveldt, A. J.

    1985-04-01

    Subthreshold parallel pumping experiments on [C 6H 11NH 3]CuBr 3 (abbreviated as CHAB) and [C 6H 11NH 3]CuCl 3 (CHAC) at 9.6 and 18.3 GHz are reported. It is shown that the experimental results can be explained using the values of the parameters as have been obtained from previously reported FMR measurements.

  6. Apoptotic effect of novel Schiff Based CdCl2(C14H21N3O2) complex is mediated via activation of the mitochondrial pathway in colon cancer cells

    PubMed Central

    Hajrezaie, Maryam; Paydar, Mohammadjavad; Looi, Chung Yeng; Moghadamtousi, Soheil Zorofchian; Hassandarvish, Pouya; Salga, Muhammad Saleh; Karimian, Hamed; Shams, Keivan; Zahedifard, Maryam; Majid, Nazia Abdul; Ali, Hapipah Mohd; Abdulla, Mahmood Ameen

    2015-01-01

    The development of metal-based agents has had a tremendous role in the present progress in cancer chemotherapy. One well-known example of metal-based agents is Schiff based metal complexes, which hold great promise for cancer therapy. Based on the potential of Schiff based complexes for the induction of apoptosis, this study aimed to examine the cytotoxic and apoptotic activity of a CdCl2(C14H21N3O2) complex on HT-29 cells. The complex exerted a potent suppressive effect on HT-29 cells with an IC50 value of 2.57 ± 0.39 after 72 h of treatment. The collapse of the mitochondrial membrane potential and the elevated release of cytochrome c from the mitochondria to the cytosol indicate the involvement of the intrinsic pathway in the induction of apoptosis. The role of the mitochondria-dependent apoptotic pathway was further proved by the significant activation of the initiator caspase-9 and the executioner caspases-3 and -7. In addition, the activation of caspase-8, which is associated with the suppression of NF-κB translocation to the nucleus, also revealed the involvement of the extrinsic pathway in the induced apoptosis. The results suggest that the CdCl2(C14H21N3O2) complex is able to induce the apoptosis of colon cancer cells and is a potential candidate for future cancer studies. PMID:25764970

  7. 77 FR 74487 - Agency Information Collection Activities: Petition for Alien Fiance(e), Form Number I-129F...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-12-14

    ...-0001] Agency Information Collection Activities: Petition for Alien Fiance(e), Form Number I-129F... information collection. (2) Title of the Form/Collection: Petition for Alien Fiance(e). (3) Agency form number... petition for an alien fiance(e), spouse, or his/her children. (5) An estimate of the total number of...

  8. (C6N2H16)[Co(H2O)6](SO4)2.2H2O: A new hybrid material based on sulfate templated by diprotonated trans-1,4-diaminocyclohexane

    NASA Astrophysics Data System (ADS)

    Hamdi, N.; Ngopoh, F. A. I.; da Silva, I.; El Bali, B.; Lachkar, M.

    2018-03-01

    Employing trans-1,4-diaminocyclohexane (DACH) as template, the new hybrid sulphate (C6N2H16)[Co(H2O)6](SO4)2.2H2O was prepared in solution. Single-crystal X-ray diffraction analysis shows that it crystallizes in the monoclinic system (S.G.: P 21/n), with the following unit-cell parameters (Å,°): a = 6.2897(2), b = 12.3716(6), c = 13.1996(4), β = 98.091(3) V = 1016.89(7) Å3, Z = 4. Its 3D crystal structure is made upon isolated [Co(H2O)6] octahedra, regular [SO4] tetrahedra, protonated DACH and free H2O molecules, which interact through N-H···O and O-H···O hydrogen bonds. The Fourier transform infrared result exhibits bands corresponding to the vibrations of DACH, sulfate group and water molecules. The thermal decomposition of the phase consists mainly in the loss of the organic moiety and one sulfate group, leading thus to the formation of anhydrous cobalt sulfate.

  9. Suggestion for search of cyclopropenone (c-C3H2O) in a cosmic object

    NASA Astrophysics Data System (ADS)

    Sharma, M. K.; Sharma, M.; Chandra, S.

    2017-03-01

    Following Minimum Energy Principle, out of the three isomers of chemical formula C3H2O, the cyclopropenone (c-C3H2O) is the most stable and therefore may be the most abundant and easily detectable in a cosmic object. The cyclopropenone is detected in Sgr B2(N). Owing to half-spin of each of two hydrogen atoms, the c-C3H2O has two distinct ortho and para species. Using the rotational and centrifugal distortion constants along with the electric dipole moment, we have calculated energies of 100 rotational levels of each of the ortho and para species of c-C3H2O and the Einstein A-coefficients for radiative transitions between the levels. The values of Einstein A-coefficients along with the scaled values for collisional rate coefficients are used for solving a set of statistical equilibrium equations coupled with the equations of radiative transfer. Brightness temperatures of seven rotational transitions of each of the ortho and para species of c-C3H2O are investigated. Out of fourteen transitions, seven are found to show anomalous absorption and rest seven are found to show emission feature. We find that the transitions 110 -111 (1.544 GHz) may play important role in identification of cyclopropenone in a cosmic object.

  10. Insight into the CH3NH3PbI3/C interface in hole-conductor-free mesoscopic perovskite solar cells

    NASA Astrophysics Data System (ADS)

    Li, Jiangwei; Niu, Guangda; Li, Wenzhe; Cao, Kun; Wang, Mingkui; Wang, Liduo

    2016-07-01

    process of CH3NH3PbI3. The derived reaction kinetics allows a quantitative description of the perovskite formation process. In addition, we found that the interfacial contact between carbon and perovskite was dominant for hole extraction efficiency and associated with the photovoltaic parameter of short circuit current density (JSC). Consequently, we conducted a solvent vapor assisted process of PbI2 diffusion to carefully control the CH3NH3PbI3/C interface with less unreacted PbI2 barrier. The improvement of interface conditions thereby contributes to a high hole extraction proved by the charge extraction resistance and PL lifetime change, resulting in the increased JSC valve. Electronic supplementary information (ESI) available: Fig. S1-S11, Tables S1, S2 and details of the Avrami model for reaction kinetics. See DOI: 10.1039/c6nr03359h

  11. A Search for Interstellar Oxiranecarbonitrile (C3H3NO)

    NASA Technical Reports Server (NTRS)

    Dicken, J. E.; Irvine, W. M.; Ohishi, M.; Arrhenius, G.; Bauder, A.; Mueller, F.; Eschenmoser, A.

    1996-01-01

    We report a search in cold, quiescent and in 'hot core' type interstellar molecular clouds for the small cyclic molecule oxiranecarbonitrile (C3H3NO), which has been suggested as a precursor of important prebiotic molecules. We have determined upper limits to the column density and fractional abundance for the observed sources and find that, typically, the fractional abundance by number relative to molecular hydrogen Of C3H3NO is less than a few times 10(exp -10). This limit is one to two orders of magnitude less than the measured abundance of such similarly complex species as CH3CH2CN and HCOOCH3 in well-studied hot cores. A number of astrochemical discoveries were made, including the first detection of the species CH3CH2CN in the massive star-forming clouds G34.3+0.2 and W51M and the first astronomical detections of some eight rotational transitions of CH3CH2CN, CH3CCH, and HCOOCH3. In addition, we found 8 emission lines in the 89 GHz region and 18 in the 102 GHz region which we were unable to assign.

  12. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Notice of Internet Availability of Proxy Materials, annual report to security holders or information... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Annual report to be furnished security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE...

  13. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... Notice of Internet Availability of Proxy Materials, annual report to security holders or information... 17 Commodity and Securities Exchanges 3 2012-04-01 2012-04-01 false Annual report to be furnished security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE...

  14. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... Notice of Internet Availability of Proxy Materials, annual report to security holders or information... 17 Commodity and Securities Exchanges 3 2013-04-01 2013-04-01 false Annual report to be furnished security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE...

  15. Solid-Contact pH Sensor without CO2 Interference with a Superhydrophobic PEDOT-C14 as Solid Contact: The Ultimate "Water Layer" Test.

    PubMed

    Guzinski, Marcin; Jarvis, Jennifer M; D'Orazio, Paul; Izadyar, Anahita; Pendley, Bradford D; Lindner, Ernő

    2017-08-15

    The aim of this study was to find a conducting polymer-based solid contact (SC) for ion-selective electrodes (ISEs) that could become the ultimate, generally applicable SC, which in combination with all kinds of ion-selective membranes (ISMs) would match the performance characteristics of conventional ISEs. We present data collected with electrodes utilizing PEDOT-C 14 , a highly hydrophobic derivative of poly(3,4-ethylenedioxythiophene), PEDOT, as SC and compare its performance characteristics with PEDOT-based SC ISEs. PEDOT-C 14 has not been used in SC ISEs previously. The PEDOT-C 14 -based solid contact (SC) ion-selective electrodes (ISEs) (H + , K + , and Na + ) have outstanding performance characteristics (theoretical response slope, short equilibration time, excellent potential stability, etc.). Most importantly, PEDOT-C 14 -based SC pH sensors have no CO 2 interference, an essential pH sensors property when aimed for whole-blood analysis. The superhydrophobic properties (water contact angle: 136 ± 5°) of the PEDOT-C 14 SC prevent the detachment of the ion-selective membrane (ISM) from its SC and the accumulation of an aqueous film between the ISM and the SC. The accumulation of an aqueous film between the ISM and its SC has a detrimental effect on the sensor performance. Although there is a test for the presence of an undesirable water layer, if the conditions for this test are not selected properly, it does not provide an unambiguous answer. On the other hand, recording the potential drifts of SC electrodes with pH-sensitive membranes in samples with different CO 2 levels can effectively prove the presence or absence of a water layer in a short time period.

  16. Crystallographic isomorphism in the structural type of α-HgI{sub 2} by example of KHgI{sub 3} · H{sub 2}O, β-Ag{sub 2}HgI{sub 4}, and β-Cu{sub 2}HgI{sub 4}

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

    Borisov, S. V., E-mail: borisov@niic.nsc.ru; Magarill, S. A.; Pervukhina, N. V.

    The structure of KHgI{sub 3} · H{sub 2}O is assigned to the family of crystal structures having the three-layer cubic packing of iodine anions with cations in the tetrahedral voids (the structures of α-HgI{sub 2}, β-Ag{sub 2}HgI{sub 4}, and β-Cu{sub 2}HgI{sub 4} among them). Crystallographic analysis shows that the nodes of the three-layer close packing are populated by iodine anions and K cations in the ratio 3/4: 1/4. Transformation of the structure of α-HgI{sub 2} into the structure of KHgI{sub 3} · H{sub 2}O can be formally represented as the replacement of (HgI){sub n}{sup +} fragments by (KH{sub 2}O){sub n}{supmore » +} fragments: (Hg{sub 2}I{sub 4})–(HgI){sup +} + (KH{sub 2}O){sub n}{sup +} = KHgI{sub 3} · H{sub 2}O. Perforated layers of vertex-sharing HgI{sub 4} tetrahedra break down into parallel isolated chains. Channels formed in place of I–Hg–I–Hg–fragments are occupied by–H{sub 2}O–K–-H{sub 2}-O-K-H{sub 2}O-chains weakly bound to neighbors.« less

  17. Diffuse X-ray scattering from benzil, C(14)H(10)O(2): analysis via automatic refinement of a Monte Carlo model.

    PubMed

    Welberry, T R; Goossens, D J; Edwards, A J; David, W I

    2001-01-01

    A recently developed method for fitting a Monte Carlo computer-simulation model to observed single-crystal diffuse X-ray scattering has been used to study the diffuse scattering in benzil, diphenylethanedione, C(6)H(5)-CO-CO-C(6)H(5). A model involving 13 parameters consisting of 11 intermolecular force constants, a single intramolecular torsional force constant and a local Debye-Waller factor was refined to give an agreement factor, R = [summation operator omega(Delta I)(2)/summation operator omega I(obs)(2)](1/2), of 14.5% for 101,324 data points. The model was purely thermal in nature. The analysis has shown that the diffuse lines, which feature so prominently in the observed diffraction patterns, are due to strong longitudinal displacement correlations. These are transmitted from molecule to molecule via a network of contacts involving hydrogen bonding of an O atom on one molecule and the para H atom of the phenyl ring of a neighbouring molecule. The analysis also allowed the determination of a torsional force constant for rotations about the single bonds in the molecule. This is the first diffuse scattering study in which measurement of such internal molecular torsion forces has been attempted.

  18. The Tritiated Water Skin Barrier Integrity Test: Considerations for Acceptance Criteria with and Without 14C-Octanol.

    PubMed

    Lehman, Paul A; Beatch, Kacie; Raney, Sam G; Franz, Thomas J

    2017-01-01

    A study was designed to assess barrier integrity simultaneously using separate compounds (probes) for polar and non-polar pathways through the skin, 3 H 2 O and 14 C-octanol, respectively; and to determine whether the two probe approach could better define barrier integrity. A 5-min dose of water containing 3 H 2 O and 14 C -octanol was applied to ex vivo human skin mounted in Franz diffusion cells. The receptor solution was sampled at 30 min, analyzed for 3 H and 14 C content, and the correlation between water and octanol absorption was determined by statistical tests suitable for non-normally distributed data. This study was conducted on skin from 37 donors with from 3 to 30 replicate skin sections per donor (a total of 426 sections). The correlation between 3 H 2 O and 14 C-octanol absorption was low (Pearson correlation coefficient = 0.3485). The 3 H 2 O absorption cutoff used in this study to select for a normal skin barrier rejected some sections in which 14 C-octanol absorption was within normal limits and accepted others in which 14 C-octanol absorption was abnormally high. The converse was true for 3 H 2 O absorption when the 14 C-octanol-based cutoff was used. The results of the 3 H 2 O test or of similar tests that primarily assess the permeability of polar pathways through the skin may not necessarily provide information relevant to the absorption of highly lipophilic compounds. Octanol, or another molecule that more closely matches the physicochemical attributes of the test compound, may characterize properties of the skin barrier that are more relevant to compounds of low water solubility.

  19. Genetic basis of HDL variation in 129/SvImJ and C57BL/6J mice: importance of testing candidate genes in targeted mutant mice.

    PubMed

    Su, Zhiguang; Wang, Xiaosong; Tsaih, Shirng-Wern; Zhang, Aihong; Cox, Allison; Sheehan, Susan; Paigen, Beverly

    2009-01-01

    To evaluate the effect of genetic background on high-density lipoprotein cholesterol (HDL) levels in Soat1(-/-) mice, we backcrossed sterol O-acyltransferase 1 (Soat1)(-/-) mice, originally reported to have elevated HDL levels, to C57BL/6 mice and constructed a congenic strain with only a small region (3.3Mb) of 129 alleles, specifically excluding the nearby apolipoprotein A-II (Apoa2) gene from 129. HDL levels in these Soat1(-/-) mice were no different from C57BL/6, indicating that the passenger gene Apoa2 caused the previously reported elevation of HDL in these Soat1(-/-) mice. Because many knockouts are made in strain 129 and then subsequently backcrossed into C57BL/6, it is important to identify quantitative trait loci (QTL) that differ between 129 and C57BL/6 so that one can guard against effects ascribed to a knockout but really caused by a passenger gene from 129. To provide such data, we generated 528 F(2) progeny from an intercross of 129S1/SvImJ and C57BL/6 and measured HDL concentrations in F(2) animals first fed chow and then atherogenic diet. A genome wide scan using 508 single-nucleotide polymorphisms (SNPs) identified 19 QTL, 2 of which were male specific and 2 were female specific. Using comparative genomics and haplotype analysis, we narrowed QTL on chromosomes 3, 5, 8, 17, and 18 to 0.5, 6.3, 2.6, 1.1, and 0.6 Mb, respectively. These data will serve as a reference for any effort to test the impact of candidate genes on HDL using a knockout strategy.

  20. Metabolic fate and distribution of [{sup 14}C]1,3-dichloropropene in carrot, lettuce, radish, tomato, and wheat

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

    Barnkow, D.E.; Byrne, S.L.; Huskin, M.A.

    1996-10-01

    This study examined the nature of the radioactive residue in carrot, lettuce, radish, tomato, and wheat grown in soil treated with uniformly {sup 14}C-labeled cis- and trans-1,3-dichloropropene (1,3-D). Each crop was grown in soil treated at or above the maximum use rate. Carrot root and top, lettuce, radish root and top, tomato fruit and vine, and wheat forage, straw and grain were harvested, processed, and analyzed. The {sup 14}C residues were subjected to sequential extraction with diethyl ether and aqueous acetonitrile. The residues that remained were subjected to extraction, fractionation, and hydrolysis with buffer, enzymes, acid, alkali, and strong oxidizingmore » agents. Analyses of the solubilized residues demonstrated that no detectable parent, 1,3-D, or the putative metabolites 3-chloroallyl alcohol and 3-chloroacrylic acid were present. The components of the extractable residue included most major plant constituents (i.e., protein, pigments, organic acids, sucrose, cellulose, and lignin). Thus, natural incorporation of the {sup 14}C-label into natural plant biochemicals is demonstrated.« less

  1. Synthesis and properties of 4-alkoxy-2-[2-hydroxy-3-(4-o,m,p-halogenoaryl-1 -piperazinyl)propyl]-6-methyl-1H-pyrrolo-[3,4-c]pyridine-1,3(2H)-diones with analgesic and sedative activities.

    PubMed

    Sladowska, Helena; Sabiniarz, Aleksandra; Szkatuła, Dominika; Filipek, Barbara; Sapa, Jacek

    2006-01-01

    Synthesis of N-substituted derivatives of 4-alkoxy-6-methyl-1H-pyrrolo[3,4-c]pyridine-1,3(2H)-diones (17-26) is described. The chlorides, containing OH group, used in the above synthesis can exist in two isomeric forms: chain (12, 14-16) and cyclic (12a, 14a-16a). All final imides studied exhibited analgesic activity in the "writhing syndrome" test which was superior than that of acetylsalicylic acid. In the "hot plate" test only two compounds (19, 20) were active as antinociceptive agents. Furthermore, all compounds tested significantly suppressed the spontaneous locomotor activity of mice.

  2. Structure and Bonding analysis of the cationic electrophilic phosphinidene complexes of iron, ruthenium, and osmium [(η(5)-C5Me5)(CO)2M{PN(i)Pr2}]+, [(η(5)-C5H5)(CO)2M{PNR2}]+ (R = Me, (i)Pr), and [(η(5)-C5H5)(PMe3)2M{PNMe2}]+ (M = Fe, Ru, Os).

    PubMed

    Pandey, Krishna K; Tiwari, Pradeep; Patidar, Pankaj

    2012-11-29

    Quantum-chemical DFT calculations for the electronic, molecular structure and M-PNR(2) bonding analyses of the experimentally known cationic electrophilic phosphinidene complexes [(η(5)-C(5)Me(5))(CO)(2)M{PN(i)Pr(2)}](+) and of the model complexes [(η(5)-C(5)H(5))(CO)(2)M{PNR(2)}](+) (R = (i)Pr, Me) and [(η(5)-C(5)H(5))(PMe(3))(2)M{PNMe(2)}](+) were carried out using BP86/TZ2P/ZORA level of theory. The calculated geometrical parameters of the studied complexes are in good agreement with the reported experimental values. The short M-P bond distances and calculated Pauling bond orders (range of 1.23-1.68), suggest the presence of M-P multiple bond characters. The Hirshfeld charge analysis shows that the overall charge flows from phosphinidene ligand to metal fragment. The M-P σ-bonding orbitals are well-occupied (>1.80e). The energy decomposition analysis revealed that the contribution of the electrostatic interaction ΔE(elstat) is, in all studied complexes, significantly larger (55.2-62.6%) than the orbital interactions ΔE(orb). The orbital interactions between metal and PNR(2) in [(η(5)-C(5)H(5))(L)(2)M{PNR(2)}](+) arise mainly from M ← PNR(2) σ-donation. The π-bonding contribution (19-36%) is much smaller than the σ-bonding. The interaction energies, as well as bond dissociation energies, depend on the auxiliary ligand framework around the metal and decrease in the order (η(5)-C(5)H(5)) > (η(5)-C(5)Me(5)) and CO > PMe(3). Upon substitution of R = (i)Pr with smaller group R = Me, the M-PNR(2) bond strength slightly decreases.

  3. Expanding the Chemistry of Actinide Metallocene Bromides. Synthesis, Properties and Molecular Structures of the Tetravalent and Trivalent Uranium Bromide Complexes: (C 5Me 4R) 2UBr 2, (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br), and [K(THF)][(C 5Me 4R) 2UBr 2] (R = Me, Et)

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

    Lichtscheidl, Alejandro Gaston; Pagano, Justin K.; Scott, Brian Lindley

    The organometallic uranium species (C 5Me 4R) 2UBr 2 (R = Me, Et) were obtained by treating their chloride analogues (C 5Me 4R) 2UCl 2 (R = Me, Et) with Me 3SiBr. Treatment of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with K(O-2,6- iPr 2C 6H 3) afforded the halide aryloxide mixed-ligand complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(X) (R = Me, Et; X = Cl, Br). Complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br) (R = Me, Et) can also be synthesized by treating (C 5Me 4R) 2U(O-2,6-more » iPr 2C 6H 3)(Cl) (R = Me, Et) with Me 3SiBr, respectively. Reduction of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with KC 8 led to isolation of uranium(III) “ate” species [K(THF)][(C 5Me 5) 2UX 2] (X = Cl, Br) and [K(THF) 0.5][(C 5Me 4Et) 2UX 2] (X = Cl, Br), which can be converted to the neutral complexes (C 5Me 4R) 2U[N(SiMe 3) 2] (R = Me, Et). Analyses by nuclear magnetic resonance spectroscopy, X-ray crystallography, and elemental analysis are also presented.« less

  4. Expanding the Chemistry of Actinide Metallocene Bromides. Synthesis, Properties and Molecular Structures of the Tetravalent and Trivalent Uranium Bromide Complexes: (C 5Me 4R) 2UBr 2, (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br), and [K(THF)][(C 5Me 4R) 2UBr 2] (R = Me, Et)

    DOE PAGES

    Lichtscheidl, Alejandro Gaston; Pagano, Justin K.; Scott, Brian Lindley; ...

    2016-01-06

    The organometallic uranium species (C 5Me 4R) 2UBr 2 (R = Me, Et) were obtained by treating their chloride analogues (C 5Me 4R) 2UCl 2 (R = Me, Et) with Me 3SiBr. Treatment of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with K(O-2,6- iPr 2C 6H 3) afforded the halide aryloxide mixed-ligand complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(X) (R = Me, Et; X = Cl, Br). Complexes (C 5Me 4R) 2U(O-2,6- iPr 2C 6H 3)(Br) (R = Me, Et) can also be synthesized by treating (C 5Me 4R) 2U(O-2,6-more » iPr 2C 6H 3)(Cl) (R = Me, Et) with Me 3SiBr, respectively. Reduction of (C 5Me 4R) 2UCl 2 and (C 5Me 4R) 2UBr 2 (R = Me, Et) with KC 8 led to isolation of uranium(III) “ate” species [K(THF)][(C 5Me 5) 2UX 2] (X = Cl, Br) and [K(THF) 0.5][(C 5Me 4Et) 2UX 2] (X = Cl, Br), which can be converted to the neutral complexes (C 5Me 4R) 2U[N(SiMe 3) 2] (R = Me, Et). Analyses by nuclear magnetic resonance spectroscopy, X-ray crystallography, and elemental analysis are also presented.« less

  5. Rate Coefficients of C2H with C2H4, C2H6, and H2 from 150 to 359 K

    NASA Technical Reports Server (NTRS)

    Opansky, Brian J.; Leone, Stephen R.

    1996-01-01

    Rate coefficients for the reactions C2H with C2H4, C2H6, and H2 are measured over the temperature range 150-359 K using transient infrared laser absorption spectroscopy. The ethynyl radical is formed by photolysis of C2H2 with a pulsed excimer laser at 193 nm, and its transient absorption is monitored with a color center laser on the Q(sub 11)(9) line of the A(sup 2) Pi-Chi(sup 2) Sigma transition at 3593.68 cm(exp -1). Over the experimental temperature range 150-359 K the rate constants of C2H with C2H4, C2H6, and H2 can be fitted to the Arrhenius expressions k(sub C2H4) = (7.8 +/- 0.6) x 10(exp -11) exp[(134 +/- 44)/T], k(sub C2H6) = (3.5 +/- 0.3) x 10(exp -11) exp[(2.9 +/- 16)/T], and k(sub H2) = (1.2 +/- 0.3) x 10(exp -11) exp[(-998 +/- 57)]/T cm(exp 3) molecule(exp -1) sec(exp -1). The data for C2H with C2H4 and C2H6 indicate a negligible activation energy to product formation shown by the mild negative temperature dependence of both reactions. When the H2 data are plotted together with the most recent high-temperature results from 295 to 854 K, a slight curvature is observed. The H2 data can be fit to the non-Arrhenius form k(sub H2) = 9.2 x 10(exp -18) T(sup 2.17 +/- 0.50) exp[(-478 +/- 165)/T] cm(exp 3) molecules(exp -1) sec(exp -1). The curvature in the Arrhenius plot is discussed in terms of both quantum mechanical tunneling of the H atom from H2 to the C2H radical and bending mode contributions to the partition function.

  6. Characterization Results For The 2013 HTF 3H Evaporator Overhead Samples

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

    Washington, A. L. II

    2013-12-04

    This report tabulates the radiochemical analysis of the 3H evaporator overhead sample for {sup 137}Cs, {sup 90}Sr, and {sup 129}I to meet the requirements in the Effluent Treatment Project (ETP) Waste Acceptance Criteria (WAC) (rev. 6). This report identifies the sample receipt date, preparation method, and analysis performed in the accumulation of the listed values. All data was found to be within the ETP WAC (rev. 6) specification for the Waste Water Collection Tanks (WWCT).

  7. Observations of CH4, C2H6, and C2H2 in the stratosphere of Jupiter

    NASA Technical Reports Server (NTRS)

    Sada, P. V.; Bjoraker, G. L.; Jennings, D. E.; McCabe, G. H.; Romani, P. N.

    1998-01-01

    We have performed high-resolution spectral observations at mid-infrared wavelengths of CH4 (8.14 micrometers), C2H6 (12.16 micrometers), and C2H2 (13.45 micrometers) on Jupiter. These emission features probe the stratosphere of the planet and provide information on the carbon-based photochemical processes taking place in that region of the atmosphere. The observations were performed using our cryogenic echelle spectrometer CELESTE, in conjunction with the McMath-Pierce 1.5-m solar telescope between November 1994 and February 1995. We used the methane observations to derive the temperature profile of the jovian atmosphere in the 1-10 mbar region of the stratosphere. This profile was then used in conjunction with height-dependent mixing ratios of each hydrocarbon to determine global abundances for ethane and acetylene. The resulting mixing ratios are 3.9(+1.9)(-1.3) x 10(-6) for C2H6 (5 mbar pressure level), and 2.3 +/- 0.5 x 10(-8) for C2H2 (8 mbar pressure level), where the quoted uncertainties are derived from model variations in the temperature profile which match the methane observation uncertainties. c1998 Academic Press.

  8. Conformational Isomerism of trans-[Pt(NH2C6H11)2I2] and the Classical Wernerian Chemistry of [Pt(NH2C6H11)4]X2 (X = Cl, Br, I)1

    PubMed Central

    Johnstone, Timothy C.; Lippard, Stephen J.

    2012-01-01

    X-ray crystallographic analysis of the compound trans-[Pt(NH2C6H11)2I2] revealed the presence of two distinct conformers within one crystal lattice. This compound was studied by variable temperature NMR spectroscopy to investigate the dynamic interconversion between these isomers. The results of this investigation were interpreted using physical (CPK) and computational (molecular mechanics and density functional theory) models. The conversion of the salts [Pt(NH2C6H11)4]X2 into trans-[Pt(NH2C6H11)2X2] (X = Cl, Br, I) was also studied and is discussed here with an emphasis on parallels to the work of Alfred Werner. PMID:23554544

  9. Centrifuge-induced hypergravity: [ 3H]GABA and L-[ 14C]glutamate uptake, exocytosis and efflux mediated by high-affinity, sodium-dependent transporters

    NASA Astrophysics Data System (ADS)

    Borisova, T. A.; Himmelreich, N. H.

    The effects of centrifuge-induced hypergravity on the presynaptic events have been investigated in order to provide further insight into regulation of glutamate and GABA neurotransmission and correlation between excitatory and inhibitory responses under artificial gravity conditions. Exposure of animals to hypergravity (centrifugation of rats at 10 G for 1 h) has been found to cause changes in the synaptic processes of brain, in particular neurotransmitter release and uptake in rat brain synaptosomes. Hypergravity loading resulted in more than two-fold enhancement of GABA transporter activity ( Vmax increased from 1.4 ± 0.3 nmol/min/mg of protein in the control group to 3.3 ± 0.59 nmol/min/mg of protein for the animals exposed to hypergravity ( P ⩽ 0.05)). The maximal velocity of L-[ 14C]glutamate uptake decreased from 12.5 ± 3.2 to 5.6 ± 0.9 nmol/min/mg of protein under artificial gravity conditions. Depolarization-evoked exocytotic release of the neurotransmitters has also changed in response to hypergravity. It increased for GABA (7.2 ± 0.54% and 11.74 ± 1.2% of total accumulated label for control and hypergravity, respectively ( P ⩽ 0.05)), but reduced for glutamate (14.4 ± 0.7% and 6.2 ± 1.9%, for control and hypergravity, respectively). Thus, comparative analysis of the neurotransmitter uptake and release has demonstrated that short-term centrifuge-induced 10 G hypergravity loading intensified inhibitory and attenuated excitatory processes in nerve terminals. The activation or reduction of neurotransmitter uptake appeared to be coupled with similarly directed alterations of the neurotransmitter release.

  10. Synthesis and biological evaluation of new 2-(4,5-dihydro-1H-imidazol-2-yl)-3,4-dihydro-2H-1,4-benzoxazine derivatives.

    PubMed

    Touzeau, Frédérique; Arrault, Axelle; Guillaumet, Gérald; Scalbert, Elizabeth; Pfeiffer, Bruno; Rettori, Marie-Claire; Renard, Pierre; Mérour, Jean-Yves

    2003-05-08

    2-(4,5-Dihydro-1H-imidazol-2-yl)-3,4-dihydro-2H-1,4-benzoxazine derivatives and tricyclic analogues with a fused additional ring on the nitrogen atom of the benzoxazine moiety have been prepared and evaluated for their cardiovascular effects as potential antihypertensive agents. The imidazoline ring was generated by reaction of the corresponding ethyl ester with ethylenediamine. Affinities for imidazoline binding sites (IBS) I(1) and I(2) and alpha(1) and alpha(2) adrenergic receptors were evaluated as well as the effects on mean arterial blood pressure (MAP) and heart rate (HR) of spontaneously hypertensive rats. With few exceptions the most active compounds on MAP were those with high affinities for IBS and alpha(2) receptor. Among these, compound 4h was the most interesting and is now, together with its enantiomers, under complementary pharmacological evaluation.

  11. Spin-forbidden and spin-allowed cyclopropenone (c-H{sub 2}C{sub 3}O) formation in interstellar medium

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

    Ahmadvand, Seyedsaeid; Zaari, Ryan R.; Varganov, Sergey A., E-mail: svarganov@unr.edu

    2014-11-10

    Three proposed mechanisms of cyclopropenone (c-H{sub 2}C{sub 3}O) formation from neutral species are studied using high-level electronic structure methods in combination with nonadiabatic transition state and collision theories to deduce the likelihood of each reaction mechanism under interstellar conditions. The spin-forbidden reaction involving the singlet electronic state of cyclopenylidene (c-C{sub 3}H{sub 2}) and the triplet state of atomic oxygen is studied using nonadiabatic transition state theory to predict the rate constant for c-H{sub 2}C{sub 3}O formation. The spin-allowed reactions of c-C{sub 3}H{sub 2} with molecular oxygen and acetylene with carbon monoxide were also investigated. The reaction involving the ground electronicmore » states of acetylene and carbon monoxide has a very large reaction barrier and is unlikely to contribute to c-H{sub 2}C{sub 3}O formation in interstellar medium. The spin-forbidden reaction of c-C{sub 3}H{sub 2} with atomic oxygen, despite the high probability of nonadiabatic transition between the triplet and singlet states, was found to have a very small rate constant due to the presence of a small (3.8 kcal mol{sup –1}) reaction barrier. In contrast, the spin-allowed reaction between c-C{sub 3}H{sub 2} and molecular oxygen is found to be barrierless, and therefore can be an important path to the formation of c-H{sub 2}C{sub 3}O molecule in interstellar environment.« less

  12. Isolated oxygen defects in 3C- and 4H-SiC: A theoretical study

    NASA Astrophysics Data System (ADS)

    Gali, A.; Heringer, D.; Deák, P.; Hajnal, Z.; Frauenheim, Th.; Devaty, R. P.; Choyke, W. J.

    2002-09-01

    Ab initio calculations in the local-density approximation have been carried out in SiC to determine the possible configurations of the isolated oxygen impurity. Equilibrium geometry and occupation levels were calculated. Substitutional oxygen in 3C-SiC is a relatively shallow effective mass like double donor on the carbon site (OC) and a hyperdeep double donor on the Si site (OSi). In 4H-SiC OC is still a double donor but with a more localized electron state. In 3C-SiC OC is substantially more stable under any condition than OSi or interstitial oxygen (Oi). In 4H-SiC OC is also the most stable one except for heavy n-type doping. We propose that OC is at the core of the electrically active oxygen-related defect family found by deep level transient spectroscopy in 4H-SiC. The consequences of the site preference of oxygen on the SiC/SiO2 interface are discussed.

  13. Synthesis of polycyclic molecules by double C(sp2)-H/C(sp3)-H arylations with a single palladium catalyst.

    PubMed

    Pierre, Cathleen; Baudoin, Olivier

    2011-04-01

    Polycyclic molecules were obtained in good yields by double C(sp(2))-H/C(sp(3))-H arylations mediated by a single palladium/phosphine catalyst. Both double intermolecular/intramolecular and intramolecular/intramolecular C-C couplings were performed successfully, which indicates that this concept has a broad applicability for the rapid construction of molecular complexity.

  14. A simple hydrogen-bonded chain in (3Z)-3-{1-[(5-phenyl-1H-pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one, and a hydrogen-bonded ribbon of centrosymmetric rings in the self-assembled adduct (3Z)-3-{1-[(5-methyl-1H-pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one-6-(2-hydroxyethyl)-2,5-dimethylpyrazolo[1,5-a]pyrimidin-7(4H)-one (1/1).

    PubMed

    Quiroga, Jairo; Portilla, Jaime; Cobo, Justo; Glidewell, Christopher

    2010-01-01

    (3Z)-3-{1-[(5-Phenyl-1H-pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one, C(15)H(15)N(3)O(2), (I), and the stoichiometric adduct (3Z)-3-{1-[(5-methyl-1H-pyrazol-3-yl)amino]ethylidene}-4,5-dihydrofuran-2(3H)-one-6-(2-hydroxyethyl)-2,5-dimethylpyrazolo[1,5-a]pyrimidin-7(4H)-one (1/1), C(10)H(13)N(3)O(2).C(10)H(13)N(3)O(2), (II), in which the two components have the same composition but different constitutions, are formed in the reactions of 2-acetyl-4-butyrolactone with 5-amino-3-phenyl-1H-pyrazole and 5-amino-3-methyl-1H-pyrazole, respectively. In each compound, the furanone component contains an intramolecular N-H...O hydrogen bond. The molecules of (I) are linked into a chain by a single intermolecular N-H...O hydrogen bond, while in (II), a combination of one O-H...N hydrogen bond, within the selected asymmetric unit, and two N-H...O hydrogen bonds link the molecular components into a ribbon containing alternating centrosymmetric R(4)(4)(20) and R(6)(6)(22) rings.

  15. 14 CFR Appendix H to Part 141 - Ground Instructor Certification Course

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Ground Instructor Certification Course H Appendix H to Part 141 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...—Advanced. (c) Ground Instructor—Instrument. 2. Aeronautical knowledge training. (a) Each approved course...

  16. 14 CFR Appendix H to Part 141 - Ground Instructor Certification Course

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 14 Aeronautics and Space 3 2011-01-01 2011-01-01 false Ground Instructor Certification Course H Appendix H to Part 141 Aeronautics and Space FEDERAL AVIATION ADMINISTRATION, DEPARTMENT OF TRANSPORTATION...—Advanced. (c) Ground Instructor—Instrument. 2. Aeronautical knowledge training. (a) Each approved course...

  17. M1/M2 muscarinic receptor selectivity using potassium (K/sup +/)-stimulated release of (/sup 3/H)-dopamine (DA) and (/sup 14/C)-acetyl-choline (ACH) in striatum

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

    DeHaven, D.L.; Steranka, L.R.

    Raiteri et al have suggested that muscarinic receptor subtypes can be differentiated in striatal synaptosomes by the release of DA (M1) or ACh (M2). The authors attempted to replicate this finding and to characterize responses of selective and non-selective cholinergic agonists and antagonists using K+-stimulated release of transmitters from rat striatal slices. The non-selective agonists ACh, carbachol and oxotremorine stimulated release of (/sup 3/H)-DA and inhibited release of (/sup 14/C)-ACh with EC50 values of 10.6, 9.2 and 4.2 ..mu..M (DA) and 1.2, 0.77 and 0.43 ..mu..M (ACh), respectively. The M1 agonist McN-A-343-11 selectively inhibited release of DA with an EC50more » value of 4.8 ..mu..M. Pilocarpine was ineffective in this system. The M1 antagonist pirenzepine reversed the effects of 10/sup -4/ M carbachol on release with an eight-fold selectivity for release of (/sup 3/H)-DA (IC50 = 0.77 ..mu..M) vs (/sup 14/C)-ACh (IC50 = 6.3 ..mu..M). These results suggest that although this system can determine relative subtype selectivities, the results obtained in this assay do not always correlate with those obtained from phosphatidyl inositol turnover or adenylate cyclase activity.« less

  18. Rate coefficients for the reactions of C2(a(3)Pi(u)) and C2(X(1)Sigma(g)(+)) with various hydrocarbons (CH4, C2H2, C2H4, C2H6, and C3H8): a gas-phase experimental study over the temperature range 24-300 K.

    PubMed

    Páramo, Alejandra; Canosa, André; Le Picard, Sébastien D; Sims, Ian R

    2008-10-02

    The kinetics of reactions of C2(a(3)Pi(u)) and C2(X(1)Sigma(g)(+)) with various hydrocarbons (CH4, C2H2, C2H4, C2H6, and C3H8) have been studied in a uniform supersonic flow expansion over the temperature range 24-300 K. Rate coefficients have been obtained by using the pulsed laser photolysis-laser induced fluorescence technique, where both radicals were produced at the same time but detected separately. The reactivity of the triplet state was found to be significantly lower than that of the singlet ground state for all reactants over the whole temperature range of the study. Whereas C2(X(1)Sigma(g)(+)) reacts with a rate coefficient close to the gas kinetic limit with all hydrocarbons studied apart from CH4, C2(a(3)Pi(u)) appears to be more sensitive to the molecular and electronic structure of the reactant partners. The latter reacts at least one order of magnitude faster with unsaturated hydrocarbons than with alkanes, and the rate coefficients increase very significantly with the size of the alkane. Results are briefly discussed in terms of their potential astrophysical impact.

  19. Serendipitous Detection of {\\rm{H}}\\,{\\rm{I}} Absorption Sets the True Redshift of 4C +15.05 to z = 0.833

    NASA Astrophysics Data System (ADS)

    Jones, K. M.; Ghosh, T.; Salter, C. J.

    2018-06-01

    4C+15.05 (also known as NRAO 91, PKS 0202+14, or J0204+15) is a quintessential blazar. It has a luminous, variable radio spectrum, a super-luminal jet, and gamma-ray detections. Arecibo observations with the 700–800 MHz receiver on the 305 m diameter William E. Gordon Telescope detected, serendipitously, H I in absorption against 4C+15.05 while using it as a bandpass calibrator for another object in an H I absorption project. Although the redshift we derive is different from that commonly in use in the literature (nominally z = 0.405), it agrees very well with the value of z = 0.833 determined by Stickel et al. This absorption feature is best fitted by a sum of three Gaussians, which yield an average redshift of z = 0.8336 ± 0.0004, although without corresponding high-resolution imaging it is not possible to say whether the components are parts of outflows or inflows. A total column density of N(H I) = 2.39 ± 0.13 × 1021 cm‑2 is derived, relatively high compared to many radio-loud sources. These results are compared to various relationships in the literature.

  20. Pharmacokinetics and bioavailability of spectinomycin after i.v., i.m., s.c. and oral administration in broiler chickens.

    PubMed

    Abu-Basha, E A; Gehring, R; Albwa'neh, S J

    2007-04-01

    A pharmacokinetic and bioavailability study of spectinomycin was conducted in healthy broiler chickens following administration of a single (50 mg/kg bw) intravenous (i.v.), intramuscular (i.m.) and subcutaneous (s.c.) dose and oral doses of 50 and 100 mg/kg bw. Following i.v. administration, the elimination half-life (t1/2beta), mean residence time (MRT), volume of distribution at steady-state (Vd(ss)), volume of distribution based on the terminal phase (Vd(z)) and total body clearance (ClB) were 1.46+/-1.10 h, 1.61+/-1.05 h, 0.26+/-0.009 L/kg, 0.34 (0.30-0.38) L/kg and 2.68+/-0.017 mL/min/kg respectively. After i.m. and s.c. dosing, the Cmax was 152.76+/-1.08 and 99.77+/-1.04 microg/mL, achieved at 0.25 (0.25-0.50) and 0.25 (0.25-1.00) h, the t1/2beta was 1.65+/-1.07 and 2.03+/-1.06 h and the absolute bioavailability (F) was 136.1% and 128.8% respectively. A significant difference in Cmax (5.13+/-0.10, 14.26+/-1.12 microg/mL), t1/2beta (3.74+/-1.07, 8.93+/-1.13 h) and ClB/F (22.69+/-0.018, 10.14+/-0.018 mL/min/kg) were found between the two oral doses (50 and 100 mg/kg bw respectively), but there were no differences in the tmax [2.00 (2.00-4.00), 2.00 (2.00-2.00) h] and Vd(z)/F [6.95 (6.34-9.06), 7.98 (4.75-10.62) L/kg). The absolute bioavailability (F) of spectinomycin was 11.8% and 26.4% after oral administration of 50 and 100 mg/kg bw respectively.

  1. An In Silico Study on the Isomers of Pentacene: The Case for Air-Stable and Alternative C22H14 Acenes for Organic Electronics.

    PubMed

    Jones, Leighton; Lin, Long

    2017-04-13

    Pentacene is one of the most investigated candidates for organic thin film transistor (OTFT) applications over the last few decades even though it unstable in air (E g = 1.80 eV), owing in part to its planar nature and high charge-transfer mobilities as both a single crystal (35 cm 2 V -1 s -1 ) and as a thin-film (3.0 cm 2 V -1 s -1 ). Until now, picene is the only isomer of pentacene to be investigated for organic electronic applications, due to its greater stability (E g = 4.21 eV) and high-charge transfer mobility (3.0 cm 2 V -1 s -1 ); even benefiting from oxygen doping. In the present study, a total of 12 fused-ring isomers (including pentacene, picene and ten other structures) of the formula C 22 H 14 were analyzed and investigated for their electronic and optical properties for worth in OTFT applications. We screened several pure and hybrid DFT functionals against the experimental frontier molecular orbitals (FMOs) of pentacene, then deployed Marcus Theory, Koopmans' Theorem and Green's function with the P3 electron propagator variant, for the internal hole reorganization energy, the hole transfer integral (via the "splitting-in-dimer method" at d = 3.0, 3.5, and 4.0 Å), the charge transfer rate constant, and vertical ionization energies. Using these as a basis, we studied pentacene's isomers and found that the four nonplanar structures, namely, benzo[g]chrysene (3), naphtho[c]phenanthrene (7), benzo[c]chrysene (11) and dibenzo[c,c']phenthrene (12), are (I) more stable than pentacene, by up to 2 eV, and (II) have relatively similar ionization energies (7.5-7.6 eV) to those of picene's experimental value (7.51 eV). The largest charge transfer rates at 3.5 Å dimer separations were given by the isomers benzo[b]chrysene 4, naphtha[c]phenanthrene 7, dibenzo[a,c]anthracene 8 and benzo[a]tetracene 10 and found to be 2.92, 1.72, 1.30, and 3.09 × 10 14 s -1 respectively. In comparison to that of pentacene (K CT = 3.97 × 10 14 s -1 ), these unusual isomers are

  2. FUN3D Manual: 12.9

    NASA Technical Reports Server (NTRS)

    Biedron, Robert T.; Carlson, Jan-Renee; Derlaga, Joseph M.; Gnoffo, Peter A.; Hammond, Dana P.; Jones, William T.; Kleb, Bil; Lee-Rausch, Elizabeth M.; Nielsen, Eric J.; Park, Michael A.; hide

    2016-01-01

    This manual describes the installation and execution of FUN3D version 12.9, including optional dependent packages. FUN3D is a suite of computational fluid dynamics simulation and design tools that uses mixed-element unstructured grids in a large number of formats, including structured multiblock and overset grid systems. A discretely-exact adjoint solver enables efficient gradient-based design and grid adaptation to reduce estimated discretization error. FUN3D is available with and without a reacting, real-gas capability. This generic gas option is available only for those persons that qualify for its beta release status.

  3. X-ray study of the hetero ring flexibility in 5,6-tri-, 5,6-tetra- and 5,6-penta-methylene-2,3,5,6-tetrahydro-1,3-oxazin-4-ones. The structures of 2-spiropentamethylene- cis-5,6-tetramethylene-2,3,5,6-tetrahydro-1,3-oxazin-4-one (I), 2-spiropentamethylene- cis-5,6-pentamethylene-2,3,5,6-tetrahydro-1,3-oxazin-4-one ( c-II) and 2-spiropentamethylene- trans-5,6-pentamethylene-2,3,5,6-tetrahydro-1,3-oxazin-4-one ( t-II)

    NASA Astrophysics Data System (ADS)

    Ribár, B.; Kapor, Á.; Kálmán, A.; Argay, Gy.; Fülöp, F.; Bernáth, G.

    1989-01-01

    The structures of the title compounds were established by X-ray crystallography by means of direct methods. Crystals of compound I (C 12H 19NO 2) are monoclinic, space group P2 1/ n, with a = 11.365(3), b = 10.343(4), c = 10.343(2) Å, β = 110.25(3)°, Z = 4 and Dc = 1.218 g cm -3. Crystals of compound c- II (C 13H 21NO 2) are monoclinic, space group C2/ c, with a = 20.830(8), b = 6.594(4), c = 17.944(8) Å, β = 95.83(2)°, Z = 8 and Dc = 1.209 g cm -3. Crystals of t- II (C 13H 21NO 2) are also monoclinic, space group P2 1/ n, with a = 14.268(4), b = 6.112(3), c = 14.041(7) Å, β = 93.63(3)°, Z = 4 and Dc = 1.210 g cm -3. The structures were refined to R = 0.059 for 1697 reflections of I, R = 0.052 for 1718 reflections of c- II, and R = 0.057 for 2178 reflections of t- II. The conformations of the 1,3-oxazin-4-one moieties in the title compounds were compared with those found earlier in related compounds. As shown by an analysis of the puckering parameters (D. Cremer and J.A. Pople, J. Am. Chem. Soc., 97 (1975) 1354), they cluster in a random distribution around the 1H 6 half-chair form. Marked deviation from this canonical form towards the 1E envelope was observed only under the influence of the cyclopentane ring.

  4. 17 CFR 240.14c-3 - Annual report to be furnished security holders.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... Notice of Internet Availability of Proxy Materials, annual report to security holders or information... 17 Commodity and Securities Exchanges 4 2014-04-01 2014-04-01 false Annual report to be furnished security holders. 240.14c-3 Section 240.14c-3 Commodity and Securities Exchanges SECURITIES AND EXCHANGE...

  5. Substrate-Mediated C-C and C-H Coupling after Dehalogenation.

    PubMed

    Kong, Huihui; Yang, Sha; Gao, Hongying; Timmer, Alexander; Hill, Jonathan P; Díaz Arado, Oscar; Mönig, Harry; Huang, Xinyan; Tang, Qin; Ji, Qingmin; Liu, Wei; Fuchs, Harald

    2017-03-15

    Intermolecular C-C coupling after cleavage of C-X (mostly, X = Br or I) bonds has been extensively studied for facilitating the synthesis of polymeric nanostructures. However, the accidental appearance of C-H coupling at the terminal carbon atoms would limit the successive extension of covalent polymers. To our knowledge, the selective C-H coupling after dehalogenation has not so far been reported, which may illuminate another interesting field of chemical synthesis on surfaces besides in situ fabrication of polymers, i.e., synthesis of novel organic molecules. By combining STM imaging, XPS analysis, and DFT calculations, we have achieved predominant C-C coupling on Au(111) and more interestingly selective C-H coupling on Ag(111), which in turn leads to selective synthesis of polymeric chains or new organic molecules.

  6. Comparison of cyclosporine determinations in whole blood by three different methods. HPLC, /sup 125/I RIA and /sup 3/H RIA

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

    Huang, W.Y.; Lipsey, A.I.; Cheng, M.H.

    1987-04-01

    The authors have analyzed and compared the cyclosporine concentrations in whole blood specimens from pediatric renal transplant patients using three different methods: high-performance liquid chromatography (HPLC) (5u C18 reverse-phase column), /sup 3/H radioimmunoassay (RIA), and /sup 125/I RIA (substituted /sup 3/H-tracer in Sandoz Kit with /sup 125/I tracer. Results obtained by the /sup 125/I RIA correlated well with results obtained by the /sup 3/H RIA. Both RIA methods had similar correlation with the HPLC method. The /sup 125/I RIA method showed higher sensitivity and greater precision than the /sup 3/H RIA method. The authors conclude that the /sup 125/I RIAmore » method can be used for cyclosporine determination in whole blood specimens. The use of the /sup 125/I RIA provides a simple and rapid method with higher counting efficiency and less background quenching than the /sup 3/H RIA method, which requires cumbersome liquid scintillation counting procedures.« less

  7. Testosterone enhances C-14 2-deoxyglucose uptake by striated muscle. [sex hormones and muscle

    NASA Technical Reports Server (NTRS)

    Toop, J.; Max, S. R.

    1982-01-01

    The effect of testosterone propionate (TP) on C-14 2-deoxyglucose (C-14 2DG) uptake was studied in the rat levator ani muscle in vivo using the autoradiographic technique. Following a delay of 1 to 3 h after injecting TP, the rate of C-14 2DG uptake in experimental animals began to increase and continued to increase for at least 20 h. The label, which corresponds to C-14 2-deoxyglucose 6-phosphate, as demonstrated by chromatographic analysis of muscle extracts, was uniformly distributed over the entire muscle and was predominantly in muscle fibers, although nonmuscular elements were also labeled. The 1 to 3 h time lag suggests that the TP effect may be genomic, acting via androgen receptors, rather than directly on muscle membranes. Acceleration of glucose uptake may be an important early event in the anabolic response of the rat levator ani muscle to androgens.

  8. Analogues of Cis- and Transplatin with a Rich Solution Chemistry: cis-[PtCl2 (NH3 )(1-MeC-N3)] and trans-[PtI2 (NH3 )(1-MeC-N3)].

    PubMed

    Siebel, Sabine; Dammann, Claudia; Sanz Miguel, Pablo J; Drewello, Thomas; Kampf, Gunnar; Teubner, Natascha; Bednarski, Patrick J; Freisinger, Eva; Lippert, Bernhard

    2015-12-01

    Mono(nucleobase) complexes of the general composition cis-[PtCl2 (NH3 )L] with L=1-methylcytosine, 1-MeC (1 a) and L=1-ethyl-5-methylcytosine, as well as trans-[PtX2 (NH3 )(1-MeC)] with X=I (5 a) and X=Br (5 b) have been isolated and were characterized by X-ray crystallography. The Pt coordination occurs through the N3 atom of the cytosine in all cases. The diaqua complexes of compounds 1 a and 5 a, cis-[Pt(H2 O)2 (NH3 )(1-MeC)](2+) and trans-[Pt(H2 O)2 (NH3 )(1-MeC)](2+) , display a rich chemistry in aqueous solution, which is dominated by extensive condensation reactions leading to μ-OH- and μ-(1-MeC(-) -N3,N4)-bridged species and ready oxidation of Pt to mixed-valence state complexes as well as diplatinum(III) compounds, one of which was characterized by X-ray crystallography: h,t-[{Pt(NH3 )2 (OH)(1-MeC(-) -N3,N4)}2 ](NO3 )2 ⋅2 [NH4 ](NO3 )⋅2 H2 O. A combination of (1) H NMR spectroscopy and ESI mass spectrometry was applied to identify some of the various species present in solution and the gas phase, respectively. As it turned out, mass spectrometry did not permit an unambiguous assignment of the structures of +1 cations due to the possibilities of realizing multiple bridging patterns in isomeric species, the occurrence of different tautomers, and uncertainties regarding the Pt oxidation states. Additionally, compound 1 a was found to have selective and moderate antiproliferative activity for a human cervix cancer line (SISO) compared to six other human cancer cell lines. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Purine 3':5'-cyclic nucleotides with the nucleobase in a syn orientation: cAMP, cGMP and cIMP.

    PubMed

    Řlepokura, Katarzyna Anna

    2016-06-01

    Purine 3':5'-cyclic nucleotides are very well known for their role as the secondary messengers in hormone action and cellular signal transduction. Nonetheless, their solid-state conformational details still require investigation. Five crystals containing purine 3':5'-cyclic nucleotides have been obtained and structurally characterized, namely adenosine 3':5'-cyclic phosphate dihydrate, C10H12N5O6P·2H2O or cAMP·2H2O, (I), adenosine 3':5'-cyclic phosphate 0.3-hydrate, C10H12N5O6P·0.3H2O or cAMP·0.3H2O, (II), guanosine 3':5'-cyclic phosphate pentahydrate, C10H12N5O7P·5H2O or cGMP·5H2O, (III), sodium guanosine 3':5'-cyclic phosphate tetrahydrate, Na(+)·C10H11N5O7P(-)·4H2O or Na(cGMP)·4H2O, (IV), and sodium inosine 3':5'-cyclic phosphate tetrahydrate, Na(+)·C10H10N4O7P(-)·4H2O or Na(cIMP)·4H2O, (V). Most of the cyclic nucleotide zwitterions/anions [two from four cAMP present in total in (I) and (II), cGMP in (III), cGMP(-) in (IV) and cIMP(-) in (V)] are syn conformers about the N-glycosidic bond, and this nucleobase arrangement is accompanied by Crib-H...Npur hydrogen bonds (rib = ribose and pur = purine). The base orientation is tuned by the ribose pucker. An analysis of data obtained from the Cambridge Structural Database made in the context of syn-anti conformational preferences has revealed that among the syn conformers of various purine nucleotides, cyclic nucleotides and dinucleotides predominate significantly. The interactions stabilizing the syn conformation have been indicated. The inter-nucleotide contacts in (I)-(V) have been systematized in terms of the chemical groups involved. All five structures display three-dimensional hydrogen-bonded networks.

  10. Unexpected formation of 1-[4-chloromethylphenyl]-5-[4-(methylsulfonyl)benzyl]-1H-tetrazole and 1-[4-chloromethylphenyl]-5-[4-(aminosulfonyl)phenyl]-1H-tetrazole: Crystal structure, bioassay screening and molecular docking studies

    NASA Astrophysics Data System (ADS)

    Jawabrah Al-Hourani, Baker; Ali, Basem F.; Judeh, Zaher; El-Barghouthi, Musa I.; Al-Awaida, Wajdy; Snobar, Yasmin; El Soubani, Fatima; Matalka, Khalid; Wuest, Frank

    2018-07-01

    During the cyclization reaction of benzyl alcohol containing amides, using NaN3 and SiCl4, additional unique chlorination development was observed to yield the novel azoles 1-[4-chloromethylphenyl]-5-[4-(methylsulfonyl)benzyl]-1H-tetrazole (3a) and 1-[4-chloromethylphenyl]-5-[4-(aminosulfonyl)phenyl]-1H-tetrazole (3b). Control experiments showed that the SiCl4 or SiCl3N3 has the major role for such functional group transformation in such a clean reaction and quantitative yield. Their molecular structures have been ascertained using the X-ray crystallography technique in addition to the spectroscopic analyses. Both compounds 3a and 3b crystallize in the monoclinic space group P21/c. The cell parameters of azole 3a are a = 22.3827 (8), Å, b = 5.1602 (2) Å, c = 13.4994 (5) Å3, β = 95.2352 (14)°, V = 1552.67 (10) Å3, and Z = 4. While the cell parameters of azole 3b are a = 20.582 (2), Å, b = 5.8947 (7) Å, c = 13.0796 (16) Å3, β = 104.376 (4)°, V = 1537.2 (3) Å3, and Z = 4. The central tetrazole ring of both compounds is planar and bears (4-chloromethylphenyl) at position one (N-1) of the central moiety. However, the substituents 4-(methylsulfonyl)phenyl and 4-(aminosulfonyl)phenyl of azoles 3a and 3b, respectively, are attached to the C-5 of the same central unit. The phenyl rings at N-1, (C2sbnd C7) and C9sbnd C14 in (3a); (C2sbnd C7) and (C8sbnd C14) in (3b) are inclined compared to the tetrazole ring with dihedral angles of 21.74° and 83.94° in 3a and 25.85° and 65.13° in 3b. The two phenyl rings, at N-1 and C-5, are rotated against each other by 87.73° (in 3a) and 72.21° (in 3b). In the crystal, intermolecular interactions between molecules of 3a,b are dominated by Csbnd H⋯O and Csbnd H⋯N hydrogen bonds. Additional Cl…π interactions add extra supramolecularity. All intermolecular interaction motifs consolidate a three dimensional network lattice. The molecular docking studies were carried out to understand the interaction of

  11. Catalysis to the disfavored product. The case of ([eta][sup 5]-C[sub 5]H[sub 5])Mo(CO)[sub 3

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

    Balla, J.; Bakac, A.; Espenson, J.H.

    1994-04-01

    The title compound is a 17e organometallic radical, which ordinarily recombines to the dimer in many solvents, including acetonitrile. In the presence of 1,4-(Me[sub 2]N)[sub 2]C[sub 6]H[sub 4] (TMPD), however, the radical disproportionates to ([eta][sup 5]-C[sub 5]H[sub 5])Mo(CO)[sub 3[sup [minus

  12. The metabolism of 14C-cyclohexylamine in mice and two strains of rat.

    PubMed

    Roberts, A; Renwick, A G

    1985-06-01

    After administration of 14C-cyclohexylamine (35-500 mg/kg) to male mice and rats, 80% of the dose of 14C was excreted in the urine, mostly within the first 24 h after dosing. In Wistar rats, 7-9% of the 14C in the 0-24 h urine was present as cis-4-aminocyclohexanol, with a similar amount as the corresponding 3-isomers. In the DA rat, only 1-2% of the 14C, and in mouse less than 1% of the 14C was present in the urine as aminocyclohexanols; unchanged cyclohexylamine accounted for about 95% of the activity. The extent of metabolism was not affected by either dose or route of administration. The species differences in metabolism may be implicated in the differences in toxicity during chronic high-dose administration.

  13. Ab Initio Reaction Kinetics of CH 3 O$$\\dot{C}$$(=O) and $$\\dot{C}$$H 2 OC(=O)H Radicals

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

    Tan, Ting; Yang, Xueliang; Ju, Yiguang

    The dissociation and isomerization kinetics of the methyl ester combustion intermediates methoxycarbonyl radical (CH3Omore » $$\\dot{C}$$(=O)) and (formyloxy)methyl radical ($$\\dot{C}$$H2OC(=O)H) are investigated theoretically using high-level ab initio methods and Rice–Ramsperger–Kassel–Marcus (RRKM)/master equation (ME) theory. Geometries obtained at the hybrid density functional theory (DFT) and coupled cluster singles and doubles with perturbative triples correction (CCSD(T)) levels of theory are found to be similar. We employ high-level ab initio wave function methods to refine the potential energy surface: CCSD(T), multireference singles and doubles configuration interaction (MRSDCI) with the Davidson–Silver (DS) correction, and multireference averaged coupled-pair functional (MRACPF2) theory. MRSDCI+DS and MRACPF2 capture the multiconfigurational character of transition states (TSs) and predict lower barrier heights than CCSD(T). The temperature- and pressure-dependent rate coefficients are computed using RRKM/ME theory in the temperature range 300–2500 K and a pressure range of 0.01 atm to the high-pressure limit, which are then fitted to modified Arrhenius expressions. Dissociation of CH3O$$\\dot{C}$$(=O) to $$\\dot{C}$$H3 and CO2 is predicted to be much faster than dissociating to CH3$$\\dot{O}$$ and CO, consistent with its greater exothermicity. Isomerization between CH3O$$\\dot{C}$$(=O) and $$\\dot{C}$$H2OC(=O)H is predicted to be the slowest among the studied reactions and rarely happens even at high temperature and high pressure, suggesting the decomposition pathways of the two radicals are not strongly coupled. The predicted rate coefficients and branching fractions at finite pressures differ significantly from the corresponding high-pressure-limit results, especially at relatively high temperatures. Finally, because it is one of the most important CH3$$\\dot{O}$$ removal mechanisms under atmospheric conditions, the reaction kinetics of

  14. Sc2C2@D3h(14246)-C74: A Missing Piece of the Clusterfullerene Puzzle.

    PubMed

    Wang, Yaofeng; Tang, Qiangqiang; Feng, Lai; Chen, Ning

    2017-02-20

    Clusterfullerenes with variable carbon cages have been extensively studied in recent years. However, despite all these efforts, C 74 cage-based clusterfullerene remains a missing piece of the puzzle. Herein, we show that single-crystal X-ray crystallographic analysis unambiguously assigns the previously reported dimetallofullerene Sc 2 @C 76 to a novel carbide clusterfullerene, Sc 2 C 2 @D 3h (14246)-C 74 , the first experimentally proven clusterfullerene with a C 74 cage. In addition, Sc 2 C 2 @D 3h (14246)-C 74 was charaterized by mass spectrometry, ultraviolet-visible-near-infrared absorption spectroscopy, 45 Sc nuclear magnetic resonance, and cyclic voltammetry. Comparative studies of the motion of the carbide cluster in Sc 2 C 2 @D 3h (14246)-C 74 and Sc 2 C 2 @C 2n (n = 40-44) revealed that a combination of factors, involving both the shape and size of the cage, is crucial in dictating the cluster motion. Moreover, structural studies of D 3h (14246)-C 74 revealed that it can be easily converted to C s (10528)-C 72 and T d (19151)-C 76 cages via C 2 desertion/insertion and Stone-Wales transformation. This suggests that D 3h (14246)-C 74 might play an important role in the growth pathway of clusterfullerenes.

  15. Chelation of /sup 238/Pu(IV) in vivo by 3,4,3-LICAM(C): Effects of ligand methylation and pH

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

    Durbin, P.W.; White, D.L.; Jeung, N.L.

    1989-06-01

    The linear tetracarboxycatecholate ligand, 3,4,3-LICAM(C) N1,N5,N10,N14-tetrakis(2,3-dihydroxy-4-carboxybenzoyl-tetraaza tet radecane, tetra sodium salt) injected within 1 h after injection of Pu(IV) citrate, removes about the same fraction of Pu from animals as CaNa3-DTPA but removes less inhaled Pu than CaNa3-DTPA and leaves a Pu residue in the renal cortex. However, the formation constant of the expected Pu-3,4,3-LICAM(C) complexes are orders of magnitude greater than that of Pu-DTPA, and 3,4,3-LICAM(C) is 100 times more efficient than CaNa3-DTPA for removing Pu from transferrin in vitro. Because the formation constants of their actinide complexes are central to in vivo actinide chelation, ligand design strategies aremore » dominated by the search for ligands with large Pu complex stabilities, and it was necessary to explain the failure of 3,4,3-LICAM(C) to achieve its thermodynamic potential in vivo. All the batches of 3,4,3-LICAM(C) prepared at Berkeley or in France (Euro-LICAM(C)) were found by high-pressure liquid chromatography to be mixtures of the pure ligand (55% in Berkeley preparations, 8.5% in Euro-LICAM(C)) and its four methylesters. A revised synthesis for 3,4,3-LICAM(C) is appended to this report. All of the incompletely hydrolyzed 3,4,3-LICAM(C) preparations and the pure ligand were tested for removal of Pu from mice (238Pu(IV) citrate intravenous, 30 mumol kg-1 of ligand at 1 h, kill at 24 h, radioanalyze tissues and separated excretal). The presence of methylesters did not significantly impair the ability of the ligands to remove Pu from mice, and it did not alter the fraction of injected Pu deposited in kidneys. Temporary elevation (reduction) of plasma and urine pH of mice by 0.5 mL of 0.1 M NaHCO3 (NH4Cl) injected before or simultaneously with pure 3,4,3-LICAM(C) somewhat improved (significantly reduced) Pu excretion but had little influence on Pu deposition in kidneys.« less

  16. Felix Spectroscopy of Likely Astronomical Molecular Ions: HC_3O^+, C_2H_3CNH^+, and C_2H_5CNH^+

    NASA Astrophysics Data System (ADS)

    Thorwirth, Sven; Asvany, Oskar; Brünken, Sandra; Jusko, Pavol; Schlemmer, Stephan; Martin-Drumel, Marie-Aline; McCarthy, Michael C.

    2017-06-01

    Infrared signatures of three molecular ions of relevance to the interstellar medium and planetary atmospheres have been detected at the Free Electron Laser for Infrared eXperiments, FELIX, at Radboud University (Nijmegen, The Netherlands) in combination with the 4K FELion 22-pole ion trap facility. Mid-infrared vibrational modes of protonated tricarbon monoxide, HC_3O^+, protonated vinyl cyanide, C_2H_3CNH^+, and protonated ethyl cyanide, C_2H_5CNH^+, were detected using resonant photodissociation of the respective Ne-complexes by monitoring the depletion of their cluster mass signal as a function of wavenumber. The infrared fingerprints compare very favorably with results from high-level quantum-chemical calculations performed at the CCSD(T) level of theory.

  17. Differential effects of hGH and IGF-I on body proportions.

    PubMed

    Laron, Zvi; Silbergeld, Aviva; Kauli, Rivka

    2012-07-01

    The differential growth effects of hGH and IGF-I on the upper/lower (U/L) body segment in relation to height (Ht) were analyzed in 15 patients with isolated Growth hormone deficiency (IGHD,:7M, 8F) mean age 5.0 +/- 3.2 (SD) years treated with hGH; 21 patients with multiple pituitary hormone deficiency including growth hormone (MPHD: 14M, 7F) aged 10.0 +/- 3.8, treated with hGH; 9 patients with Laron Syndrome (LS) (4M,5F) aged 6.9 +/- 5.6 years treated with IGF-I; 9 boys with intrauterine growth retardation (IUGR) aged 6.3 +/- 1.25 years treated by hGH; and 22 boys with idiopathic short stature (ISS) aged 8.0 +/- 1.55 years treated by hGH. The dose of hGH was 33 microg/kg/day, that of IGF-I 180-200 microg/kg/day. the U/L body segment ratio in IGHD patients decreased from 2.3 +/- 0.7 to 1.1 +/- 0.7 (p <0.001), and the Ht SDS increased from -4.9 +/- 1.3 to 2.3 +/- 1 (p < 0.001) following treatment. In MPHD patients the U/L body segment decreased from 1.1 +/- 1.1 to -0.6 +/- 1.0 (p < 0.001), and the Ht SDS increased from -3.3 +/- 1.4 to -2.5 +/- 1.0 (p < 0.009). In the LS group the U/L body segment ratio did not change with IGF-I treatment but Ht improved from -6.1 +/- 1.3 to -4.6 +/- 1.2 (p < 0.001), The differential growth response of the children with IUGR and with ISS resembled that of the children with LS. hGH and IGF-I act differentially on the spine and limbs.

  18. Detection of interstellar ethylene oxide (c-C2H4O).

    PubMed

    Dickens, J E; Irvine, W M; Ohishi, M; Ikeda, M; Ishikawa, S; Nummelin, A; Hjalmarson, A

    1997-11-10

    We report the identification of 10 transitions that support the detection of the small cyclic molecule ethylene oxide (c-C2H4O) in Sgr B2N. Although one of these transitions is severely blended, so that an accurate intensity and line width could not be determined, and two other lines are only marginally detected, we have done Gaussian fits to the remaining seven lines and have performed a rotation diagram analysis. Our results indicate a rotation temperature T(rot) = 18 K and a molecular column density N(c-C2H4O) = 3.3 x 10(14) cm-2, corresponding to a fractional abundance relative to molecular hydrogen of order 6 x 10(-11). This is a factor of more than 200 higher than the abundance for this molecule suggested by the "new standard" chemistry model of Lee, Bettens, & Herbst. This result suggests that grain chemistry might play an effective role in the production of c-C2H4O. No transitions of this molecule were detected in either Sgr B2M or Sgr B2NW.

  19. Immobilization and bonding scheme of radioactive iodine-129 in silver tellurite glass

    NASA Astrophysics Data System (ADS)

    Lee, Cheong Won; Pyo, Jae-Young; Park, Hwan-Seo; Yang, Jae Hwan; Heo, Jong

    2017-08-01

    Silver tellurite glasses with melting temperatures < 700 °C were prepared to immobilize the 129I that normally volatilizes during high-temperature melting. Glasses have densities of 6.31 ± 0.1 g/cm3 and glass transition temperatures of 165 ± 3 °C that provide thermal stability at the disposal site. Iodine waste loading in glasses was as high as 12.64 wt% of all metallic elements and 11.21 wt% including oxygen. Normalized elemental releases obtained from the product consistency test were well below US regulation of 2 g/m2. Iodines are surrounded by four Ag+ ions forming [Ag4I]3+ units that are further connected to tellurite network through bonds with non-bridging oxygens.

  20. Theoretical microwave spectral constants for C2N, C2N/+/, and C3H

    NASA Technical Reports Server (NTRS)

    Green, S.

    1980-01-01

    Theoretical microwave spectral constants have been computed for C2N, C3H, and C2N(+). For C2N these are compared with values obtained from optical data. Calculated hyperfine constants are also presented for HNC, DNC, and HCNH(+). The possibility of observing these species in dense interstellar clouds is discussed.

  1. {beta}-K{sub 4}La{sub 6}I{sub 14}Os: A new structure type for rare-earth-metal cluster compounds that contains discrete tetrahedral K{sub 4}I{sup 3+} units

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

    Uma, S.; Corbett, J.D.

    1999-08-23

    Suitable reactions of KI, La, LaI{sub 3}, and Os in niobium tubes at 800--850 C result in black, air- and moisture-sensitive crystals of the quaternary title phase. Isostructural K{sub 4}Pr{sub 6}I{sub 14}Z also exist for Z = Fe, Ru. The title phase was characterized by single-crystal X-ray diffraction (tetragonal, P4/ncc (No. 130), Z = 4; a = 13.117(3), c = 25.17(1) {angstrom} at 23 C). The important structural feature is the constitution (K{sub 4}I){sup 3+}(La{sub 6}I{sub 13}Os{sup 3{minus}}) with a new type of 3D anion network of [(La{sub 6}Os)I{sub 8}{sup i}I{sub 4/2}{sup i{minus}a}I{sub 4/2}{sup a{minus}i}I{sub 2/2}{sup a{minus}a}] clusters that aremore » connected into puckered layers through I{sup i{minus}a} and I{sup a{minus}i} atom pairs that bridge diagonally in the a-b plane. These cluster layers are further interlinked along {rvec c} at trans-vertexes through simple bridging I{sup a{minus}a}. The 14th iodine atom occurs in the unique K{sub 4}I{sup 3+} ions which lie in columns that interpenetrate the La{sub 6}OsI{sub 13} network along c. The present 16-e{sup {minus}} clusters, in contrast with the optimal 18-e{sup {minus}} octahedral cluster configuration, exhibit an uncommon tetragonal elongation and evidently become closed shell, with only a small temperature-independent (van Vleck-like) paramagnetism, {approximately}4 x 10{sup {minus}4} emu mol{sup {minus}1}.« less

  2. The polyadenosine RNA-binding protein ZC3H14 interacts with the THO complex and coordinately regulates the processing of neuronal transcripts.

    PubMed

    Morris, Kevin J; Corbett, Anita H

    2018-06-15

    The polyadenosine RNA-binding protein ZC3H14 is important in RNA processing. Although ZC3H14 is ubiquitously expressed, mutation of the ZC3H14 gene causes a non-syndromic form of intellectual disability. Here, we examine the function of ZC3H14 in the brain by identifying ZC3H14-interacting proteins using unbiased mass spectrometry. Through this analysis, we identified physical interactions between ZC3H14 and multiple RNA processing factors. Notably, proteins that comprise the THO complex were amongst the most enriched proteins. We demonstrate that ZC3H14 physically interacts with THO components and that these proteins are required for proper RNA processing, as loss of ZC3H14 or THO components leads to extended bulk poly(A) tail length. Furthermore, we identified the transcripts Atp5g1 and Psd95 as shared RNA targets of ZC3H14 and the THO complex. Our data suggest that ZC3H14 and the THO complex are important for proper processing of Atp5g1 and Psd95 RNA, as depletion of ZC3H14 or THO components leads to decreased steady-state levels of each mature transcript accompanied by accumulation of Atp5g1 and Psd95 pre-mRNA in the cytoplasm. Taken together, this work provides the first unbiased identification of nuclear ZC3H14-interacting proteins from the brain and links the functions of ZC3H14 and the THO complex in the processing of RNA.

  3. Highly Efficient Performance and Conversion Pathway of Photocatalytic CH3SH Oxidation on Self-Stabilized Indirect Z-Scheme g-C3N4/I3--BiOI.

    PubMed

    Hu, Lingling; He, Huanjunwa; Xia, Dehua; Huang, Yajing; Xu, Jiarong; Li, Haoyue; He, Chun; Yang, Wenjing; Shu, Dong; Wong, Po Keung

    2018-06-06

    A self-stabilized Z-scheme porous g-C 3 N 4 /I 3- -containing BiOI ultrathin nanosheets (g-C 3 N 4 /I 3- -BiOI) heterojunction photocatalyst with I 3 - /I - redox mediator was successfully synthesized by a facile solvothermal method coupling with light illumination. The structure and optical properties of g-C 3 N 4 /I 3- -BiOI composites were systematically characterized by means of X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared, X-ray photoelectron spectroscopy, N 2 adsorption/desorption, UV-vis diffuse reflectance spectrum, and photoluminescence. The g-C 3 N 4 /I 3- -BiOI composites, with a heterojunction between porous g-C 3 N 4 and BiOI ultrathin nanosheets, were first applied for the photocatalytic elimination of ppm-leveled CH 3 SH under light-emitting diode visible light illumination. The g-C 3 N 4 /I 3- -BiOI heterojunction with 10% g-C 3 N 4 showed a dramatically enhanced photocatalytic activity in the removal of CH 3 SH compared with pure BiOI and g-C 3 N 4 due to its effective interfacial charge transfer and separation. The adsorption and photocatalytic oxidation of CH 3 SH over g-C 3 N 4 /I 3- -BiOI were deeply explored by in situ diffuse reflectance infrared Fourier transform spectroscopy, and the intermediates and conversion pathways were elucidated and compared. Furthermore, on the basis of reactive species trapping, electron spin resonance and Mott-Schottky experiments, it was revealed that the responsible reactive species for catalytic CH 3 SH composition were h + , • O 2 - , and 1 O 2 ; thus, the g-C 3 N 4 /I 3- -BiOI heterojunction followed an indirect all-solid state Z-scheme charge-transfer mode with self-stabilized I 3 - /I - pairs as redox mediator, which could accelerate the separation of photogenerated charge and enhance the redox reaction power of charged carriers simultaneously.

  4. The interstellar chemistry of H2C3O isomers

    PubMed Central

    Loison, Jean-Christophe; Agúndez, Marcelino; Marcelino, Núria; Wakelam, Valentine; Hickson, Kevin M.; Cernicharo, José; Gerin, Maryvonne; Roueff, Evelyne; Guélin, Michel

    2016-01-01

    We present the detection of two H2C3O isomers, propynal and cyclopropenone, toward various starless cores and molecular clouds, together with upper limits for the third isomer propadienone. We review the processes controlling the abundances of H2C3O isomers in interstellar media showing that the reactions involved are gas-phase ones. We show that the abundances of these species are controlled by kinetic rather than thermodynamic effects. PMID:27013768

  5. Transmutation of 129I and 237Np using spallation neutrons produced by 1.5, 3.7 and 7.4 GeV protons

    NASA Astrophysics Data System (ADS)

    Wan, J.-S.; Schmidt, Th.; Langrock, E.-J.; Vater, P.; Brandt, R.; Adam, J.; Bradnova, V.; Bamblevski, V. P.; Gelovani, L.; Gridnev, T. D.; Kalinnikov, V. G.; Krivopustov, M. I.; Kulakov, B. A.; Sosnin, A. N.; Perelygin, V. P.; Pronskikh, V. S.; Stegailov, V. I.; Tsoupko-Sitnikov, V. M.; Modolo, G.; Odoj, R.; Phlippen, P.-W.; Zamani-Valassiadou, M.; Adloff, J. C.; Debeauvais, M.; Hashemi-Nezhad, S. R.; Guo, S.-L.; Li, L.; Wang, Y.-L.; Dwivedi, K. K.; Zhuk, I. V.; Boulyga, S. F.; Lomonossova, E. M.; Kievitskaja, A. F.; Rakhno, I. L.; Chigrinov, S. E.; Wilson, W. B.

    2001-05-01

    Small samples of 129I and 237Np, two long-lived radwaste nuclides, were exposed to spallation neutron fluences from relatively small metal targets of lead and uranium, that were surrounded with a 6 cm thick paraffin moderator, and irradiated with 1.5, 3.7 and 7.4 GeV protons. The (n,γ) transmutation rates were determined for these nuclides. Conventional radiochemical La- and U-sensors and a variety of solid-state nuclear track detectors were irradiated simultaneously with secondary neutrons. Compared with results from calculations with well-known cascade codes (LAHET from Los Alamos and DCM/CEM from Dubna), the observed secondary neutron fluences are larger.

  6. Graphene assisted effective hole-extraction on In2O3:H/CH3NH3PbI3 interface: Studied by modulated surface spectroscopy

    NASA Astrophysics Data System (ADS)

    Vinoth Kumar, Sri Hari Bharath; Muydinov, Ruslan; Kol'tsova, Tat‘yana; Erfurt, Darja; Steigert, Alexander; Tolochko, Oleg; Szyszka, Bernd

    2018-01-01

    Charge separation in CH3NH3PbI3 (MAPbI3) films deposited on a hydrogen doped indium oxide (In2O3:H) photoelectrode was investigated by modulated surface photovoltage (SPV) spectroscopy in a fixed capacitor arrangement. It was found that In2O3:H reproducibly extracts photogenerated-holes from MAPbI3 films. The oxygen-plasma treatment of the In2O3:H surface is suggested to be a reason for this phenomenon. Introducing graphene interlayer increased charge separation nearly 6 times as compared to that on the In2O3:H/MAPbI3 interface. Furthermore, it is confirmed by SPV spectroscopy that the defects of the MAPbI3 interface are passivated by graphene.

  7. Genetic basis of HDL variation in 129/SvImJ and C57BL/6J mice: importance of testing candidate genes in targeted mutant mice*s⃞

    PubMed Central

    Su, Zhiguang; Wang, Xiaosong; Tsaih, Shirng-Wern; Zhang, Aihong; Cox, Allison; Sheehan, Susan; Paigen, Beverly

    2009-01-01

    To evaluate the effect of genetic background on high-density lipoprotein cholesterol (HDL) levels in Soat1−/− mice, we backcrossed sterol O-acyltransferase 1 (Soat1)−/− mice, originally reported to have elevated HDL levels, to C57BL/6 mice and constructed a congenic strain with only a small region (3.3Mb) of 129 alleles, specifically excluding the nearby apolipoprotein A-II (Apoa2) gene from 129. HDL levels in these Soat1−/− mice were no different from C57BL/6, indicating that the passenger gene Apoa2 caused the previously reported elevation of HDL in these Soat1−/− mice. Because many knockouts are made in strain 129 and then subsequently backcrossed into C57BL/6, it is important to identify quantitative trait loci (QTL) that differ between 129 and C57BL/6 so that one can guard against effects ascribed to a knockout but really caused by a passenger gene from 129. To provide such data, we generated 528 F2 progeny from an intercross of 129S1/SvImJ and C57BL/6 and measured HDL concentrations in F2 animals first fed chow and then atherogenic diet. A genome wide scan using 508 single-nucleotide polymorphisms (SNPs) identified 19 QTL, 2 of which were male specific and 2 were female specific. Using comparative genomics and haplotype analysis, we narrowed QTL on chromosomes 3, 5, 8, 17, and 18 to 0.5, 6.3, 2.6, 1.1, and 0.6 Mb, respectively. These data will serve as a reference for any effort to test the impact of candidate genes on HDL using a knockout strategy. PMID:18772481

  8. Magnetic behavior of the ferromagnetic quantum chain systems (C6H11NH3)CuCl3 (CHAC) and (C6H11NH3)CuBr3 (CHAB)

    NASA Astrophysics Data System (ADS)

    Kopinga, A.; Tinus, A. M. C.; de Jonge, W. J. M.

    1982-04-01

    Heat-capacity measurements on (C6H11NH3)CuBr3 (CHAB) in the region 0.45 < T<55 K are presented. Three-dimensional ordering is observed at Tc=1.50 K. The data are analyzed together with previously reported measurements on (C6H11NH3)CuCl3 (CHAC). Both compounds appear to be very good approximations of a ferromagnetic S=12 Heisenberg linearchain system with Jk~50 K. From the data it is inferred that the intrachain interaction of CHAC contains about 2% uniaxial anisotropy, whereas CHAB contains about 5% easy-plane anisotropy. The results are corroborated by magnetization measurements on CHAB below Tc, which also reveal a metamagnetic transition for H-->∥b (Hc=210Oe). From the value of Hc and the location of the tricitical point the interchain interactions in CHAB were found as zAFJAFk=-0.03 K, zFJFk~0.08 K.

  9. Impact of maternal immune activation on maternal care behavior, offspring emotionality and intergenerational transmission in C3H/He mice.

    PubMed

    Berger, Stefanie; Ronovsky, Marianne; Horvath, Orsolya; Berger, Angelika; Pollak, Daniela D

    2018-05-01

    Maternal immune activation (MIA) is a well-established model for the investigation of the deleterious effects of gestational infection on offspring mental health later in life. Hence, MIA represents a critical environmental variable determining brain development and the depending neural and behavioral functions in the progeny. Transgenerational transmission of some of the effects of MIA has been recently reported using the Polyinosinic:polycytidylic acid (Poly (I:C)) MIA model in C57BL/6 (C57) inbred mice. However, little is known about the underlying molecular mechanisms and the possible relevance of the specific genetic make-up of the inbred mouse strain used. Here we set out to characterize the effects of gestational Poly (I:C) treatment in C3H/HeNCrl mice (C3H), focusing on maternal care and offspring depression-like behavior and its intergenerational potential. miRNA expression in the offspring hippocampus in the F1 and F2 generations was examined as possible mechanism contributing to the observed behavioral effects. The impact of MIA on maternal care and its transmission to F1 females was previously observed in C57 mice was also found in C3H mice. Depression-like behavior in the adult offspring in C3H F1 and F2 females differed from reports of the C57 strain in the literature, suggesting a potential modulating role of the genetic background in the Poly(I:C) MIA mouse model. As the pattern of expression of selected candidate miRNAs in the F1 and F2 offspring hippocampus was not conserved between the two generations, it is unlikely to be a direct consequence of altered maternal care, or to be an immediate determinant of offspring emotionality. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

  10. Transport of sup 14 C-IAA and sup 14 C-ACC within floral organs of Ipomoea nil

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

    Kiss, H.G.; Maurice, H.R.; Koning, R.E.

    1989-04-01

    The transport of {sup 14}C-IAA {sup 14}C-ACC from agarose donor blocks applied to I. nil filaments their recovery as {sup 14}C-accumulation into floral organs was examined. The accumulation of the isotopes in the corolla tissue was greater when {sup 14}C-ACC was applied than {sup 14}C-IAA in intact isolated flower buds. Greater levels of the isotopes accumulated in the pistil, with minimal levels in receptacle and calyx tissues from isolated buds. With intact buds, greater levels of the isotopes were recovered in pistil, calyx receptacle tissues. This study provides further evidence for the role of the filaments as transport vectors formore » IAA ACC for the production of ethylene.« less

  11. Experimental Determination of Solubilities of Tri-calcium Di-Citrate Tetrahydrate [Ca 3[C 3H 5O(COO) 3] 2•4H 2O] Earlandite in NaCl and MgCl 2 Solutions to High Ionic Strengths and Its Pitzer Model: Applications to Nuclear Waste Isolation and Other Low Temperature Environments

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

    Xiong, Yongliang; Kirkes, Leslie Dawn; Westfall, Terry

    In this study, solubility measurements on tri-calcium di-citrate tetrahydrate [Ca 3[C 3H 5O(COO) 3]2•4H 2O, abbreviated as Ca 3[Citrate] 2•4H 2O] as a function of ionic strength are conducted in NaCl solutions up to I = 5.0 mol•kg –1 and in MgCl 2 solutions up to I = 7.5 mol•kg –1, at room temperature (22.5 ± 0.5°C). The solubility constant (log Kmore » $$0\\atop{sp}$$) for Ca 3[Citrate] 2•4H 2O and formation constant (logβ$$0\\atop{1}$$) for Ca[C 3H 5O(COO) 3] –Ca 3[C 3H 5O(COO) 3] 2•4H 2O (earlandite) = 3Ca 2+ + 2[C 3H 5O(COO) 3] 3– + 4H 2O (1) Ca 2+ + [C 3H 5O(COO) 3] 3– = Ca[C 3H 5O(COO) 3] – (2) are determined as –18.11 ± 0.05 and 4.97 ± 0.05, respectively, based on the Pitzer model with a set of Pitzer parameters describing the specific interactions in NaCl and M gCl 2 media.« less

  12. Highly Accurate Quartic Force Fields, Vibrational Frequencies, and Spectroscopic Constants for Cyclic and Linear C3H3(+)

    NASA Technical Reports Server (NTRS)

    Huang, Xinchuan; Taylor, Peter R.; Lee, Timothy J.

    2011-01-01

    High levels of theory have been used to compute quartic force fields (QFFs) for the cyclic and linear forms of the C H + molecular cation, referred to as c-C H + and I-C H +. Specifically the 33 3333 singles and doubles coupled-cluster method that includes a perturbational estimate of connected triple excitations, CCSD(T), has been used in conjunction with extrapolation to the one-particle basis set limit and corrections for scalar relativity and core correlation have been included. The QFFs have been used to compute highly accurate fundamental vibrational frequencies and other spectroscopic constants using both vibrational 2nd-order perturbation theory and variational methods to solve the nuclear Schroedinger equation. Agreement between our best computed fundamental vibrational frequencies and recent infrared photodissociation experiments is reasonable for most bands, but there are a few exceptions. Possible sources for the discrepancies are discussed. We determine the energy difference between the cyclic and linear forms of C H +, 33 obtaining 27.9 kcal/mol at 0 K, which should be the most reliable available. It is expected that the fundamental vibrational frequencies and spectroscopic constants presented here for c-C H + 33 and I-C H + are the most reliable available for the free gas-phase species and it is hoped that 33 these will be useful in the assignment of future high-resolution laboratory experiments or astronomical observations.

  13. Effects of dexmedetomidine on H-FABP, CK-MB, cTnI levels, neurological function and near-term prognosis in patients undergoing heart valve replacement.

    PubMed

    Wang, Zhi; Chen, Qiang; Guo, Hao; Li, Zhishan; Zhang, Jinfeng; Lv, Lei; Guo, Yongqing

    2017-12-01

    This study investigated the effects of dexmedetomidine on heart-type fatty acid binding protein (H-FABP), creatine kinase isoenzymes (CK-MB), and troponin I (cTnI) levels, neurological function and near-term prognosis in patients undergoing heart valve replacement. Patients undergoing heart valve replacement were randomly allocated to remifentanil anesthesia (control group, n=48) or dexmedetomidine anesthesia (observation group, n=48). Hemodynamic parameters were measured before anesthesia induction (T1), 1 min after intubation (T2), 10 min after start of surgery (T3), and on completion of surgery (T4). Levels of plasma H-FABP, CK-MB and cTnI were measured 10 min before anesthesia induction (C1), 10 min after start of surgery (C2), on completion of surgery (C3), 6 h after surgery (C4), and 24 h after surgery (C5). S100β protein and serum neuron-specific enolase (NSE) were detected 10 min before anesthesia induction (C1), and 24 h after surgery (C5). Neurological and cardiac function was evaluated 24 h after surgery. Incidence of cardiovascular adverse events was recorded for 1 year of follow-up. There were no significant differences in the average heart rate between the two groups during the perioperative period. The mean arterial pressure in the observation group was significantly lower than control group (P<0.05). Levels of H-FABP, CK-MB and cTnI at C2, C3, C4 and C5, were significantly higher than C1, but significantly lower in the observation versus control group (P<0.05). Twenty-four hours after surgery, levels of S100β and NSE in both groups were higher than those before induction (P<0.05), but significantly lower in the observation versus control group (P<0.05). Twenty-four hours after surgery, neurological function scores were better, and myocardial contractility and arrhythmia scores significantly lower in the observation versus control group (P<0.05 for all). After follow-up for 1 year, incidence of cardiovascular adverse events was significantly lower

  14. Mechanisms whereby insulin increases diacylglycerol in BC3H-1 myocytes.

    PubMed Central

    Farese, R V; Cooper, D R; Konda, T S; Nair, G; Standaert, M L; Davis, J S; Pollet, R J

    1988-01-01

    We previously suggested that insulin increases diacylglycerol (DAG) in BC3H-1 myocytes, both by increases in synthesis de novo of phosphatidic acid (PA) and by hydrolysis of non-inositol-containing phospholipids, such as phosphatidylcholine (PC) and phosphatidylethanolamine (PE). We have now evaluated these insulin effects more thoroughly, and several potential mechanisms for their induction. In studies of the effect on PA synthesis de novo, insulin stimulated [2-3H]glycerol incorporation into PA, DAG, PC/PE and total glycerolipids of BC3H-1 myocytes, regardless of whether insulin was added simultaneously with, or after 2 h or 3 or 10 days of prelabelling with, [2-3H]glycerol. In prelabelled cells, time-related changes in [2-3H]glycerol labelling of DAG correlated well with increases in DAG content: both were maximal in 30-60 s and persisted for 20-30 min. [2-3H]Glycerol labelling of glycerol 3-phosphate, on the other hand, was decreased by insulin, presumably reflecting increased utilization for PA synthesis. Glycerol 3-phosphate concentrations were 0.36 and 0.38 mM before and 1 min after insulin treatment, and insulin effects could not be explained by increases in glycerol 3-phosphate specific radioactivity. In addition to that of [2-3H]glycerol, insulin increased [U-14C]glucose and [1,2,3-3H]glycerol incorporation into DAG and other glycerolipids. Effects of insulin on [2-3H]glycerol incorporation into DAG and other glycerolipids were half-maximal and maximal at 2 nM- and 20 nM-insulin respectively, and were not dependent on glucose concentration in the medium, extracellular Ca2+ or protein synthesis. Despite good correlation between [3H]DAG and DAG content, calculated increases in DAG content from glycerol 3-phosphate specific radioactivity (i.e. via the pathway of PA synthesis de novo) could account for only 15-30% of the observed increases in DAG content. In addition to increases in [3H]glycerol labelling of PC/PE, insulin rapidly (within 30 s) increased PC

  15. Prediction of the PVTx and VLE properties of natural gases with a general Helmholtz equation of state. Part I: Application to the CH4-C2H6-C3H8-CO2-N2 system

    NASA Astrophysics Data System (ADS)

    Mao, Shide; Lü, Mengxin; Shi, Zeming

    2017-12-01

    A general equation of state (EOS) explicit in Helmholtz free energy has been developed to predict the pressure-volume-temperature-composition (PVTx) and vapor-liquid equilibrium (VLE) properties of the CH4-C2H6-C3H8-CO2-N2 fluid mixtures (main components of natural gases). This EOS, which is a function of temperature, density and composition, with four mixing parameters used, is based on the improved EOS of Sun and Ely (2004) for the pure components (CH4, C2H6, C3H8, CO2 and N2) and contains a simple generalized departure function presented by Lemmon and Jacobsen (1999). Comparison with the experimental data available indicates that the EOS can calculate the PVTx and VLE properties of the CH4-C2H6-C3H8-CO2-N2 fluid mixtures within or close to experimental uncertainties up to 623 K and 1000 bar within full range of composition. Isochores of the CH4-C2H6-C3H8-CO2-N2 system can be directly calculated from this EOS to interpret the corresponding microthermometric and Raman analysis data of fluid inclusions. The general EOS can calculate other thermodynamic properties if the ideal Helmholtz free energy of fluids is combined, and can also be extended to the multi-component natural gases including the secondary alkanes (carbon number above three) and none-alkane components such as H2S, SO2, O2, CO, Ar and H2O. This part of work will be finished in the near future.

  16. The Path of Carbon in Photosynthesis XIII. pH Effects in C{sup 14}O{sub 2} Fixation by Scenedesmus

    DOE R&D Accomplishments Database

    Ouellet, C.; Benson, A. A.

    1951-10-23

    The rates of photosynthesis and dark fixation of C{sup 14}O{sub 2} in Scenedesmus have been compared in dilute phosphate buffers of 1.6 to 11.4 pH; determination of C{sup 14} incorporation into the various products shows enhancement of uptake in an acid medium into sucrose, polysaccharides, alanine and serine, in an alkaline medium into malic asparctic acids. kinetic experiments at extreme pH values suggest that several paths are available for CO{sub 2} assimilation. A tentative correlation of the results with the pH optima of some enzymes and resultant effects upon concentrations of intermediates is presented.

  17. Crystal structure of rivastigmine hydrogen tartrate Form I (Exelon®), C 14H 23N 2O 2(C 4H 5O 6)

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

    Kaduk, James A.; Zhong, Kai; Gindhart, Amy M.

    2016-03-08

    The crystal structure of rivastigmine hydrogen tartrate has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional techniques. Rivastigmine hydrogen tartrate crystallizes in space groupP2 1(#4) witha= 17.538 34(5),b= 8.326 89(2),c= 7.261 11(2) Å,β= 98.7999(2)°,V= 1047.929(4) Å 3, andZ= 2. The un-ionized end of the hydrogen tartrate anions forms a very strong hydrogen bond with the ionized end of another anion to form a chain. The ammonium group of the rivastigmine cation forms a strong discrete hydrogen bond with the carbonyl oxygen atom of the un-ionized end of the tartrate anion. These hydrogen bondsmore » form a corrugated network in thebc-plane. Both hydroxyl groups of the tartrate anion form intramolecular O–H···O hydrogen bonds. Several C–H···O hydrogen bonds appear to contribute to the crystal energy. The powder pattern is included in the Powder Diffraction File ™as entry 00-064-1501.« less

  18. Thermoelectric properties of the 3C, 2H, 4H, and 6H polytypes of the wide-band-gap semiconductors SiC, GaN, and ZnO

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

    Huang, Zheng; Lü, Tie-Yu; Wang, Hui-Qiong

    We have investigated the thermoelectric properties of the 3C, 2H, 4H, and 6H polytypes of the wide-band-gap(n-type) semiconductors SiC, GaN, and ZnO based on first-principles calculations and Boltzmann transport theory. Our results show that the thermoelectric performance increases from 3C to 6H, 4H, and 2H structures with an increase of hexagonality for SiC. However, for GaN and ZnO, their power factors show a very weak dependence on the polytype. Detailed analysis of the thermoelectric properties with respect to temperature and carrier concentration of 4H-SiC, 2H-GaN, and 2H-ZnO shows that the figure of merit of these three compounds increases with temperature,more » indicating the promising potential applications of these thermoelectric materials at high temperature. The significant difference of the polytype-dependent thermoelectric properties among SiC, GaN, and ZnO might be related to the competition between covalency and ionicity in these semiconductors. Our calculations may provide a new way to enhance the thermoelectric properties of wide-band-gap semiconductors through atomic structure design, especially hexagonality design for SiC.« less

  19. Uptake and metabolism of 14C-palmitate by fetal rabbit tissues.

    PubMed

    Hudson, D G; Hull, D

    1977-01-01

    The uptake and esterification of 14C-palmitate into lipid classes in placenta, fetal brown adipose tissue (BAT) and liver of rabbits were investigated in vitro. Fetal BAT showed a high rate of fatty acid uptake, 8.5 mumol-a-1 tissue-h-1. From 5 min onwards, the majority of incorporated label was in the triglyceride fraction. The placenta and fetal liver also incorporated I-[14C]-palmitate into both FFA and esterified lipid fractions, although at much lower rates than observed for BAT. In the liver, triglycerides, but in the placenta phospholipids, contained the majority of the label after 1 h incubation. BAT from both fetal and newborn rabbits released 14CO2 and the production of 14 CO2 was greater in the presence of noradrenaline. The specific activity of the CO2 was the same in stimulated and unstimulated tissue. It is concluded that BAT as well as the liver are important sites of free fatty acid removal from the fetal circulation. The potential for fatty acid oxidation is present in BAT of the 28-day rabbit fetus.

  20. Histone H3K9 Demethylase JMJD2B Activates Adipogenesis by Regulating H3K9 Methylation on PPARγ and C/EBPα during Adipogenesis

    PubMed Central

    Jang, Min-Kyung; Kim, Ji-Hyun; Jung, Myeong Ho

    2017-01-01

    Previous studies have shown that tri- or di-methylation of histone H3 at lysine 9 (H3K9me3/me2) on the promoter of the peroxisome proliferator-activated receptor γ (PPARγ) and CCAAT/enhancer-binding protein α (C/EBPα) contribute to the repression of PPARγ and C/EBPα and inhibition of adipogenesis in 3T3-L1 preadipocytes. The balance of histone methylation is regulated by histone methyltransferases and demethylases. However, it is poorly understood which demethylases are responsible for removing H3K9me3/me2 on the promoter of PPARγ and C/EBPα. JMJD2B is a H3K9me3/me2 demethylase that was previously shown to activate adipogenesis by promoting mitotic clonal expansion. Nevertheless, it remains unclear whether JMJD2B plays a role in the regulation of adipogenesis by removing H3K9me3/me2 on the promoter of PPARγ and C/EBPα and subsequently activating PPARγ and C/EBPα expression. Here, we showed that JMJD2B decreased H3K9me3/me2 on the promoter of PPARγ and C/EBPα, which in turn stimulated the expression of PPARγ and C/EBPα. JMJD2B knockdown using siRNA in 3T3-L1 preadipocytes repressed the expression of PPARγ and C/EBPα, resulting in inhibition of adipogenesis. This was accompanied by increased enrichment of H3K9me3/me2 on the promoter of PPARγ and C/EBPα. In contrast, overexpression of JMJD2B increased the expression of PPARγ and C/EBPα, which was accompanied by decreased enrichment of H3K9me3/me2 on the promoter and activated adipogenesis. Together, these results indicate that JMJD2B regulates PPARγ and C/EBPα during adipogenesis. PMID:28060835

  1. 77 FR 61776 - Agency Information Collection Activities: Petition for Alien Fiancé(e), Form I-129F, Revision of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-10-11

    ...-0001] Agency Information Collection Activities: Petition for Alien Fianc[eacute](e), Form I-129F.../Collection: Petition for Alien Fianc[eacute](e). (3) Agency form number, if any, and the applicable component... United States in order to petition for an alien fianc[eacute](e), spouse, or his/her children. (5) An...

  2. Hydrogeological and hydrochemical investigation of groundwater using environmental isotopes (18O, 2H, 3H, 14C) and chemical tracers: a case study of the intermediate aquifer, Sfax, southeastern Tunisia

    NASA Astrophysics Data System (ADS)

    Ayadi, Rahma; Trabelsi, Rim; Zouari, Kamel; Saibi, Hakim; Itoi, Ryuichi; Khanfir, Hafedh

    2018-06-01

    Major element concentrations and stable (δ18O and δ2H) and radiogenic (3H and 14C) isotopes in groundwater have proved useful tracers for understanding the geochemical processes that control groundwater mineralization and for identifying recharge sources in the semi-arid region of Sfax (southeastern Tunisia). Major-ion chemical data indicate that the origins of the salinity in the groundwater are the water-rock interactions, mainly the dissolution of evaporitic minerals, as well as the cation exchange with clay minerals. The δ18O and δ2H relationships suggest variations in groundwater recharge mechanisms. Strong evaporation during recharge with limited rapid water infiltration is evident in the groundwater of the intermediate aquifer. The mixing with old groundwater in some areas explains the low stable isotope values of some groundwater samples. Groundwaters from the intermediate aquifer are classified into two main water types: Ca-Na-SO4 and Ca-Na-Cl-SO4. The high nitrate concentrations suggest an anthropogenic source of nitrogen contamination caused by intensive agricultural activities in the area. The stable isotopic signatures reveal three water groups: non-evaporated waters that indicate recharge by recent infiltrated water; evaporated waters that are characterized by relatively enriched δ18O and δ2H contents; and mixed groundwater (old/recent) or ancient groundwater, characterized by their depleted isotopic composition. Tritium data support the existence of recent limited recharge; however, other low tritium values are indicative of pre-nuclear recharge and/or mixing between pre-nuclear and contemporaneous recharge. The carbon-14 activities indicate that the groundwaters were mostly recharged under different climatic conditions during the cooler periods of the late Pleistocene and Holocene.

  3. Hydrogeological and hydrochemical investigation of groundwater using environmental isotopes (18O, 2H, 3H, 14C) and chemical tracers: a case study of the intermediate aquifer, Sfax, southeastern Tunisia

    NASA Astrophysics Data System (ADS)

    Ayadi, Rahma; Trabelsi, Rim; Zouari, Kamel; Saibi, Hakim; Itoi, Ryuichi; Khanfir, Hafedh

    2017-12-01

    Major element concentrations and stable (δ18O and δ2H) and radiogenic (3H and 14C) isotopes in groundwater have proved useful tracers for understanding the geochemical processes that control groundwater mineralization and for identifying recharge sources in the semi-arid region of Sfax (southeastern Tunisia). Major-ion chemical data indicate that the origins of the salinity in the groundwater are the water-rock interactions, mainly the dissolution of evaporitic minerals, as well as the cation exchange with clay minerals. The δ18O and δ2H relationships suggest variations in groundwater recharge mechanisms. Strong evaporation during recharge with limited rapid water infiltration is evident in the groundwater of the intermediate aquifer. The mixing with old groundwater in some areas explains the low stable isotope values of some groundwater samples. Groundwaters from the intermediate aquifer are classified into two main water types: Ca-Na-SO4 and Ca-Na-Cl-SO4. The high nitrate concentrations suggest an anthropogenic source of nitrogen contamination caused by intensive agricultural activities in the area. The stable isotopic signatures reveal three water groups: non-evaporated waters that indicate recharge by recent infiltrated water; evaporated waters that are characterized by relatively enriched δ18O and δ2H contents; and mixed groundwater (old/recent) or ancient groundwater, characterized by their depleted isotopic composition. Tritium data support the existence of recent limited recharge; however, other low tritium values are indicative of pre-nuclear recharge and/or mixing between pre-nuclear and contemporaneous recharge. The carbon-14 activities indicate that the groundwaters were mostly recharged under different climatic conditions during the cooler periods of the late Pleistocene and Holocene.

  4. Enantioselective C(sp3)‒H bond activation by chiral transition metal catalysts.

    PubMed

    Saint-Denis, Tyler G; Zhu, Ru-Yi; Chen, Gang; Wu, Qing-Feng; Yu, Jin-Quan

    2018-02-16

    Organic molecules are rich in carbon-hydrogen bonds; consequently, the transformation of C-H bonds to new functionalities (such as C-C, C-N, and C-O bonds) has garnered much attention by the synthetic chemistry community. The utility of C-H activation in organic synthesis, however, cannot be fully realized until chemists achieve stereocontrol in the modification of C-H bonds. This Review highlights recent efforts to enantioselectively functionalize C(sp 3 )-H bonds via transition metal catalysis, with an emphasis on key principles for both the development of chiral ligand scaffolds that can accelerate metalation of C(sp 3 )-H bonds and stereomodels for asymmetric metalation of prochiral C-H bonds by these catalysts. Copyright © 2018 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.

  5. Temperature-Ramped 129Xe Spin-Exchange Optical Pumping

    PubMed Central

    2015-01-01

    We describe temperature-ramped spin-exchange optical pumping (TR-SEOP) in an automated high-throughput batch-mode 129Xe hyperpolarizer utilizing three key temperature regimes: (i) “hot”—where the 129Xe hyperpolarization rate is maximal, (ii) “warm”—where the 129Xe hyperpolarization approaches unity, and (iii) “cool”—where hyperpolarized 129Xe gas is transferred into a Tedlar bag with low Rb content (<5 ng per ∼1 L dose) suitable for human imaging applications. Unlike with the conventional approach of batch-mode SEOP, here all three temperature regimes may be operated under continuous high-power (170 W) laser irradiation, and hyperpolarized 129Xe gas is delivered without the need for a cryocollection step. The variable-temperature approach increased the SEOP rate by more than 2-fold compared to the constant-temperature polarization rate (e.g., giving effective values for the exponential buildup constant γSEOP of 62.5 ± 3.7 × 10–3 min–1 vs 29.9 ± 1.2 × 10–3 min–1) while achieving nearly the same maximum %PXe value (88.0 ± 0.8% vs 90.1% ± 0.8%, for a 500 Torr (67 kPa) Xe cell loading—corresponding to nuclear magnetic resonance/magnetic resonance imaging (NMR/MRI) enhancements of ∼3.1 × 105 and ∼2.32 × 108 at the relevant fields for clinical imaging and HP 129Xe production of 3 T and 4 mT, respectively); moreover, the intercycle “dead” time was also significantly decreased. The higher-throughput TR-SEOP approach can be implemented without sacrificing the level of 129Xe hyperpolarization or the experimental stability for automation—making this approach beneficial for improving the overall 129Xe production rate in clinical settings. PMID:25008290

  6. C-H and H-H Activation in Transition Metal Complexes and on Surfaces.

    DTIC Science & Technology

    1983-01-01

    IEEIIIIIEEEEI EEEIIEIIIIIII EEIIIEIIIEIII IIIEEEIIEIIII La.𔃻 m41. 12.2 1.4o 12.0 1.25 111.4 11. MICROCOP RE SOO TESTCHAR NATIONA BUREA OfSANAD 16m ~4 OFFICE...ML4 plane, bringing a C-H bond in proximity to the metal. The compounds will minimize M. . C-H re- -27 - pulsion by bringing the H atom into an axial...h) C-H activation has been shown also with organolanthanides and organo- actinide compounds : Watson, P.L. J.Chem.Soc. Chem.Commun. 1983, 176-177

  7. Speciation analysis of I-127,129 in the crop field soil contaminated by the Fukushima Dai-ichi nuclear power plant accident with newly developed chemical separation techniques

    NASA Astrophysics Data System (ADS)

    Honda, Maki; Matsuzaki, Hiroyuki; Saito, Takumi; Nagai, Hisao

    2014-05-01

    In previous study, we investigated the depth profile of the accident derived I-129 and downward migration speed in soils of near-field of Fukushima Dai-ichi Nuclear Power Plant, including crop fields and man-made fields. I-129 in soil was measured by AMS and stable iodine (I-127) was measured by ICP-MS at MALT (Micro Analysis Laboratory, Tandem accelerator), The University of Tokyo. It was found that I-129 was concentrated near surface but distributed deeper compared with Cs-137. It was also found that I-129 seems to move downward more quickly than Cs-137. To investigate the adsorption mechanism and the elemental process of migration of the accident derived I-129 in soil, it is important to know what kind of component the I-129 combines with. Recent studies on the X-ray absorption fine structure (XAFS), especially near edge structure (XANES), reported that the stable iodine (I-127) in soil existed as an organic component. However, it had not yet been proved that it was also the case with the accident derived I-129 because it had been incorporated in the soil system only recently and the abundance of I-129 in soil was more than 8 orders of magnitude smaller than sub-ppm level stable iodine (I-127). In this study a progressive sequential extraction method including the dialysis and the dynamic headspace method was newly developed to obtain only the iodine sticking to the soil organic component. The stable iodine can be quantified by direct analysis of the fraction and I-129 can be quantified by AMS method of the fraction added with carrier. The fraction of the organic component for I-127 and I-129 can be evaluated respectively by comparing with the other fraction and/or with the total concentration obtained by the bulk analysis (e.g. by the pyrohydrolysis).

  8. Electron scattering by the hydrocarbons C4H6,C5H8 , and C6H10

    NASA Astrophysics Data System (ADS)

    Kiataki, Matheus B.; Pastega, Diego F.; Bettega, Márcio H. F.

    2017-10-01

    We report calculated elastic integral and differential cross sections for electron collisions with the hydrocarbons 1,3-butadiene (C4H6 ), 2-methyl-1,3-butadiene (C5H8 ), and 2,3-dimethyl-1,3-butadiene (C6H10 ) for impact energies up to 15 eV. Our calculations were performed with the Schwinger Multichannel Method with pseudopotentials, in the static-exchange and static-exchange plus polarization approximations. These molecules differ for the presence of one methyl group, in the case of C5H8 , and two methyl groups, in the case of C6H10 in substitution of one and two hydrogen atoms in C4H6 , respectively (methylation effect). For the polar molecule 2-methyl-1,3-butadiene, we included the Born closure procedure in order to account for the long-range potential. We found two π* shape resonances in the integral cross section of each one of the molecules studied. The present results are also compared with the experimental values for the resonances positions and with total cross sections available in the literature. In particular, we show that the minimum in the total cross section of C5H8 located at around 1.6 eV and assigned by the authors as a Ramsauer-Townsend minimum is, actually, a valley between the two π* shape resonances. Also for the C5H8 molecule, the enhancement in the total cross section below 1.6 eV is the tail of the low-lying shape resonance and not an effect due to its permanent dipole moment, as suggested by the authors. We discuss the influence of the methylation effect in the shape and magnitude of the elastic cross sections and also in the location of the π* shape resonances of these hydrocarbons.

  9. a Comparison of the Molecular Structures of C_4H_9OCH_3, C_4H_9SCH_3, C_5H_{11}OCH_3, and C_5H_{11}SCH_3 Using Microwave Spectroscopy

    NASA Astrophysics Data System (ADS)

    Long, Brittany E.; Betancur, Juan; Choi, Yoon Jeong; Cooke, S. A.; Grubbs, G. S., II; Ogulnick, Jonathan; Holmes, Tara

    2017-06-01

    Pure rotational spectra of the title molecules have been recorded using chirped pulse Fourier transform microwave spectroscopy. Under our experimental conditions only one conformer has been observed for each of the four compounds. These conformers have torsional angles of CXCC = 180^o, XCCC = 60^o, CCCC = 180^o, and, for the C_5H_{11}-X-CH_3 species, CCCC_{Methyl} = 180^o. These angles correspond to anti-gauche-anti conformations for the butyl methyl ether/thioether species, and anti-gauche-anti-anti conformations for the pentyl methyl ether/thioether species. Splittings due to the internal rotation of the X-CH_3 group are observed in both butyl species but are not observed in the pentyl species. The barrier to the X-CH_3 internal rotation has been investigated through spectral analyses and quantum chemical calculations. The differences in the internal rotation barrier between the ethers and thioethers will be discussed and will further be compared to the barriers obtained for similar molecules.

  10. Is (18)F-FDG a surrogate tracer to measure tumor hypoxia? Comparison with the hypoxic tracer (14)C-EF3 in animal tumor models.

    PubMed

    Christian, Nicolas; Deheneffe, Stéphanie; Bol, Anne; De Bast, Marc; Labar, Daniel; Lee, John A; Grégoire, Vincent

    2010-11-01

    Fluorodeoxyglucose (FDG) has been reported as a surrogate tracer to measure tumor hypoxia with positron emission tomography (PET). The hypothesis is that there is an increased uptake of FDG under hypoxic conditions secondary to enhanced glycolysis, compensating the hypoxia-induced loss of cellular energy production. Several studies have already addressed this issue, some with conflicting results. This study aimed to compare the tracers (14)C-EF3 and (18)F-FDG to detect hypoxia in mouse tumor models. C3H, tumor-bearing mice (FSAII and SCCVII tumors) were injected iv with (14)C-EF3, and 1h later with (18)F-FDG. Using a specifically designed immobilization device with fiducial markers, PET (Mosaic®, Philips) images were acquired 1h after the FDG injection. After imaging, the device containing mouse was frozen, transversally sliced and imaged with autoradiography (AR) (FLA-5100, Fujifilm) to obtain high resolution images of the (18)F-FDG distribution within the tumor area. After a 48-h delay allowing for (18)F decay a second AR was performed to image (14)C-EF3 distribution. AR images were aligned to reconstruct the full 3D tumor volume, and were compared with the PET images. Image segmentation with threshold-based methods was applied on both AR and PET images to derive various tracer activity volumes. The matching index DSI (dice similarity index) was then computed. The comparison was performed under normoxic (ambient air, FSAII: n=4, SCCVII, n=5) and under hypoxic conditions (10% O(2) breathing, SCCVII: n=4). On AR, under both ambient air and hypoxic conditions, there was a decreasing similarity between (14)C-EF3 and FDG with higher activity sub-volumes. Under normoxic conditions, when comparing the 10% of tumor voxels with the highest (18)F-FDG or (14)C-EF3 activity, a DSI of 0.24 and 0.20 was found for FSAII and SCCVII, respectively. Under hypoxic conditions, a DSI of 0.36 was observed for SCCVII tumors. When comparing the (14)C-EF3 distribution in AR with the

  11. Volume properties and refraction of aqueous solutions of bisadducts of light fullerene C60 and essential amino acids lysine, threonine, and oxyproline (C60(C6H13N2O2)2, C60(C4H8NO3)2, and C60(C5H9NO2)2) at 25°C

    NASA Astrophysics Data System (ADS)

    Semenov, K. N.; Ivanova, N. M.; Charykov, N. A.; Keskinov, V. A.; Kalacheva, S. S.; Duryagina, N. N.; Garamova, P. V.; Kulenova, N. A.; Nabieva, A.

    2017-02-01

    Concentration dependences of the density of aqueous solutions of bisadducts of light fullerene C60 and essential amino acids are studied by pycnometry. Concentration dependences of the average molar volumes and partial volumes of components (H2O and corresponding bisadducts) are calculated for C60(C6H13N2O2)2-H2O, C60(C4H8NO3)2-H2O, and C60(C5H9NO2)2-H2O binary systems at 25°C. Concentration dependences of the indices of refraction of C60(C6H13N2O2)2-H2O, C60(C4H8NO3)2-H2O, and C60(C5H9NO2)2-H2O binary systems are determined at 25°C. The concentration dependences of specific refraction and molar refraction of bisadducts and aqueous solutions of them are calculated.

  12. Direct block of hERG potassium channels by the protein kinase C inhibitor bisindolylmaleimide I (GF109203X).

    PubMed

    Thomas, Dierk; Hammerling, Bettina C; Wimmer, Anna-Britt; Wu, Kezhong; Ficker, Eckhard; Kuryshev, Yuri A; Scherer, Daniel; Kiehn, Johann; Katus, Hugo A; Schoels, Wolfgang; Karle, Christoph A

    2004-12-01

    The human ether-a-go-go-related gene (hERG) encodes the rapid component of the cardiac repolarizing delayed rectifier potassium current, I(Kr). The direct interaction of the commonly used protein kinase C (PKC) inhibitor bisindolylmaleimide I (BIM I) with hERG, KvLQT1/minK, and I(Kr) currents was investigated in this study. hERG and KvLQT1/minK channels were heterologously expressed in Xenopus laevis oocytes, and currents were measured using the two-microelectrode voltage clamp technique. In addition, hERG currents in stably transfected human embryonic kidney (HEK 293) cells, native I(Kr) currents and action potentials in isolated guinea pig ventricular cardiomyocytes were recorded using whole-cell patch clamp electrophysiology. Bisindolylmaleimide I blocked hERG currents in HEK 293 cells and Xenopus oocytes in a concentration-dependent manner with IC(50) values of 1.0 and 13.2 muM, respectively. hERG channels were primarily blocked in the open state in a frequency-independent manner. Analysis of the voltage-dependence of block revealed a reduction of inhibition at positive membrane potentials. BIM I caused a shift of -20.3 mV in the voltage-dependence of inactivation. The point mutations tyrosine 652 alanine (Y652A) and phenylalanine 656 alanine (F656A) attenuated hERG current blockade, indicating that BIM I binds to a common drug receptor within the pore region. KvLQT1/minK currents were not significantly altered by BIM I. Finally, 1 muM BIM I reduced native I(Kr) currents by 69.2% and lead to action potential prolongation. In summary, PKC-independent effects have to be carefully considered when using BIM I as PKC inhibitor in experimental models involving hERG channels and I(Kr) currents.

  13. Bile acids. XLIV, quantitation of bile acids from the bile fistula rat given (4-14C) cholesterol.

    PubMed

    Siegfried, C M; Doisy, E A; Elliott, W H

    1975-01-24

    The bile acids derived from [4-14-C]cholesterol administered intracardially to rats with cannulated bile ducts were identified and quantitated. Over a period of 28 days about 90% of the administered 14-C was found in bile of which 73% was retained in the biliary acid fraction. [7beta-3-H]cholic acid, alpha-muri[3beta-3-H]cholic acid, beta-muri[3beta-3-H]cholic acid and litho[3beta-3-H]cholic acid were prepared with specific activities of about 30 muCi/mg by reduction of appropriate ketonic precursors with NaB3H4 and were added to the biliary acid fraction. After separation and purification of the bile acids, cholic, chenodeoxycholic, alpha- and beta-muricholic acids accounted for 70, 16, 7.5 and 6.1%, respectively, of the 14-C in the biliary acid fraction. The specific activities of these isolated 14-C-labeled acids were almost identical. Lithocholic acid accounted for a maximum of 0.2% and ursodeoxycholic acid and 7-oxolithocholic acid could account for no more than 2% of the biliary 14-C. Gas-liquid chromatography on 3% OV-17 of the trimethylsilyl ether derivatives of the methyl esters of the common bile acids of rat bile results in their complete separation and provides a convenient means of estimating the relative proportions of these acids in rat bile. By this method, the relative amounts of the four major acids, cholic, chenodeoxycholic, alpha- and beta-muricholic acids were 63, 20, 8 and 6%, respectively.

  14. Cu(I)-catalyzed transannulation of N-heteroaryl aldehydes or ketones with alkylamines via C(sp3)-H amination.

    PubMed

    Li, Mingyang; Xie, Ying; Ye, Yong; Zou, Yong; Jiang, Huanfeng; Zeng, Wei

    2014-12-05

    A copper(I)-catalyzed direct transannulation of N-heteroaryl aldehydes or ketones with alkylamines via Csp(3)-H amination has been achieved using molecular oxygen as a sole oxidant. N-Heteroarenes are employed as the amine source. This transformation provides a rapid and concise access to multifunctional imidazo[1,5-a]pyridines.

  15. Comparison of the gravimetric, phenol red, and 14C-PEG-3350 methods to determine water absorption in the rat single-pass intestinal perfusion model.

    PubMed

    Sutton, S C; Rinaldi, M T; Vukovinsky, K E

    2001-01-01

    This study was undertaken to determine whether the gravimetric method provided an accurate measure of water flux correction and to compare the gravimetric method with methods that employ nonabsorbed markers (eg, phenol red and 14C-PEG-3350). Phenol red,14C-PEG-3350, and 4-[2-[[2-(6-amino-3-pyridinyl)-2-hydroxyethyl]amino]ethoxy]-, methyl ester, (R)-benzene acetic acid (Compound I) were co-perfused in situ through the jejunum of 9 anesthetized rats (single-pass intestinal perfusion [SPIP]). Water absorption was determined from the phenol red,14C-PEG-3350, and gravimetric methods. The absorption rate constant (ka) for Compound I was calculated. Both phenol red and 14C-PEG-3350 were appreciably absorbed, underestimating the extent of water flux in the SPIP model. The average +/- SD water flux microg/h/cm) for the 3 methods were 68.9 +/- 28.2 (gravimetric), 26.8 +/- 49.2 (phenol red), and 34.9 +/- 21.9 (14C-PEG-3350). The (average +/- SD) ka for Compound I (uncorrected for water flux) was 0.024 +/- 0.005 min(-1). For the corrected, gravimetric method, the average +/- SD was 0.031 +/- 0.001 min(-1). The gravimetric method for correcting water flux was as accurate as the 2 "nonabsorbed" marker methods.

  16. Carbon Dioxide-Mediated C(sp3)-H Arylation of Amine Substrates.

    PubMed

    Kapoor, Mohit; Liu, Daniel; Young, Michael C

    2018-05-25

    Elaborating amines via C-H functionalization has been an important area of research over the past decade but has generally relied on an added directing group or sterically hindered amine approach. Since free-amine-directed C(sp 3 )-H activation is still primarily limited to cyclization reactions and to improve the sustainability and reaction scope of amine-based C-H activation, we present a strategy using CO 2 in the form of dry ice that facilitates intermolecular C-H arylation. This methodology has been used to enable an operationally simple procedure whereby 1° and 2° aliphatic amines can be arylated selectively at their γ-C-H positions. In addition to potentially serving as a directing group, CO 2 has also been demonstrated to curtail the oxidation of sensitive amine substrates.

  17. Characterization results for the October 2015-Tank for farm 3H evaporator overhead examples

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

    Nicholson, J. C.

    2016-01-28

    This report contains the radioanalytical results of the 3H evaporator overhead sample received at SRNL on October 13, 2015. Specifically, concentrations of 137Cs, 90Sr, and 129I are reported and compared to the corresponding Waste Acceptance Criteria (WAC) limits of the Effluent Treatment Project (ETP) Waste Water Collection Tank (WWCT) (rev. 6). All of the radionuclide concentrations in the sample were found to be in compliance with the ETP WAC limits.

  18. 14-3-3 sigma and 14-3-3 zeta plays an opposite role in cell growth inhibition mediated by transforming growth factor-beta 1.

    PubMed

    Hong, Hye-Young; Jeon, Woo-Kwang; Bae, Eun-Jin; Kim, Shin-Tae; Lee, Ho-Jae; Kim, Seong-Jin; Kim, Byung-Chul

    2010-03-01

    The expression of 14-3-3 proteins is dysregulated in various types of cancer. This study was undertaken to investigate the effects of 14-3-3 zeta and 14-3-3 sigma on cell growth inhibition mediated by transforming growth factor-beta 1 (TGF-beta1). Mouse mammary epithelial cells (Eph4) that are transformed with oncogenic c-H-Ras (EpRas) and no longer sensitive to TGF-beta1-mediated growth inhibition displayed increased expression of 14-3-3 zeta and decreased expression of 14-3-3 sigma compared with parental Eph4 cells. Using small interfering RNA-mediated knockdown and overexpression of 14-3-3 sigma or 14-3-3 zeta, we showed that 14-3-3 sigma is required for TGF-beta1-mediated growth inhibition whereas 14-3-3 zeta negatively modulates this growth inhibitory response. Notably, overexpression of 14-3-3 zeta increased the level of Smad3 protein that is phosphorylated at linker regions and cannot mediate the TGF-beta1 growth inhibitory response. Consistent with this finding, mutation of the 14-3-3 zeta phosphorylation sites in Smad3 markedly reduced the 14-3-3 zeta-mediated inhibition of TGF-beta1-induced p15 promoter-reporter activity and cell cycle arrest, suggesting that these residues are critical targets of 14-3-3 zeta in the suppression of TGF-beta1-mediated growth. Taken together, our findings indicate that dysregulation of 14-3-3 sigma or 14-3-3 zeta contributes to TGF-beta1 resistance in cancer cells.

  19. Formation of cation-anion complexes in the photochemical reaction of molybdenocene dihydrode with iron pentacarbonyl. Crystal structures of (Cp/sub 2/Mo(CO)H)/sup +/(Fe/sub 3/(CO)/sub 11/H)/sup -/ and (Cp/sub 2/Mo(CO)H)/sup +/(CoMo(CO)/sub 3/)/sup -/ (triclinic modification) (in Russian)

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

    Antsyshkina, A.S.; Dikareva, L.M.; Porai-Koshits, M.A.

    1985-11-01

    The reaction of Cp/sub 2/MoH/sub 2/ with Fe(CO)/sub 5/ in boiling benzene under UV irradiation gives the ionic complexes (Cp/sub 2/Mo(CO)H)/sup +/(Fe/sub 3/(CO)/sub 11/H)/sup -/ (I) and (Cp/sub 2/Mo(CO)H)/sup +/(CpMo(CO)/sub 3/)/sup -/ (II), whose structures were established by x-ray diffraction analysis (Syntex P2/sub 1/ automatic diffractometer, lambda Mo K/sub ..cap alpha../, graphite monochromator, theta/2theta scan technique, full-matrix least-squares method, isotropic variant for I on the basis of 2112 reflections to % = 0.11 and anisotropic variant for II on the basis of 3770 values of hkl to R = 0.052). In complexes I and II the (CpMo(CO)H)/sup +/ fragment ismore » a tapered sandwich with an eclipsed conformation of the rings. In complex I the angle between the rings is 33.9/sup 0/, the mean Mo-C(C/sub 5/H/sub 5/) distance is 2.28(3) A, the mean Mo-C(CO) distance is 2.03(3) A, and the mean Mo-H distance is 1.78(10) A. The corresponding parameters in complex II are: 32.4/sup 0/, 2.296(7), 2.020(6), and 1.87(7) A. The anion in complex I is based on a triangular cluster of Fe atoms, in which one Fe-Fe distance is significantly shorter (2.488(5) A) than the other two (2.702(5) and 2.697(5) A). The Fe atoms forming the short bond are joined additionally by hydride (Fe-H = 2.14 A) and carbonyl (Fe-C = 1.90(3) and 1.93(3) A) Bridges. The remaining groups are terminal. A probable scheme for the process of the formation of complexes I and II has been discussed.« less

  20. Epitaxy of boron phosphide on AlN, 4H-SiC, 3C-SiC and ZrB2 substrates

    NASA Astrophysics Data System (ADS)

    Padavala, Balabalaji

    The semiconductor boron phosphide (BP) has many outstanding features making it attractive for developing various electronic devices, including neutron detectors. In order to improve the efficiency of these devices, BP must have high crystal quality along with the best possible electrical properties. This research is focused on growing high quality crystalline BP films on a variety of superior substrates like AlN, 4H-SiC, 3C-SiC and ZrB2 by chemical vapor deposition. In particular, the influence of various parameters such as temperature, reactant flow rates, and substrate type and its crystalline orientation on the properties of BP films were studied in detail. Twin-free BP films were produced by depositing on off-axis 4H-SiC(0001) substrate tilted 4° toward [11¯00] and crystal symmetry matched zincblende 3C-SiC. BP crystalline quality improved at higher deposition temperature (1200°C) when deposited on AlN, 4H-SiC, whereas increased strain in 3C-SiC and increased boron segregation in ZrB2 at higher temperatures limited the best deposition temperature to below 1200°C. In addition, higher flow ratios of PH 3 to B2H6 resulted in smoother films and improved quality of BP on all substrates. The FWHM of the Raman peak (6.1 cm -1), XRD BP(111) peak FWHM (0.18°) and peak ratios of BP(111)/(200) = 5157 and BP(111)/(220) = 7226 measured on AlN/sapphire were the best values reported in the literature for BP epitaxial films. The undoped films on AlN/sapphire were n-type with a highest electron mobility of 37.8 cm2/V˙s and a lowest carrier concentration of 3.15x1018 cm -3. Raman imaging had lower values of FWHM (4.8 cm-1 ) and a standard deviation (0.56 cm-1) for BP films on AlN/sapphire compared to 4H-SiC, 3C-SiC substrates. X-ray diffraction and Raman spectroscopy revealed residual tensile strain in BP on 4H-SiC, 3C-SiC, ZrB2/4H-SiC, bulk AlN substrates while compressive strain was evident on AlN/sapphire and bulk ZrB2 substrates. Among the substrates studied, Al

  1. Evaluating the electronic structure of formal Ln II ions in Ln II(C 5H 4SiMe 3) 3 1– using XANES spectroscopy and DFT calculations

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

    Fieser, Megan E.; Ferrier, Maryline Ghislaine; Su, Jing

    Here, the isolation of [K(2.2.2-cryptand)][Ln(C 5H 4SiMe 3) 3], formally containing LnII, for all lanthanides (excluding Pm) was surprising given that +2 oxidation states are typically regarded as inaccessible for most 4f-elements. Herein, X-ray absorption near-edge spectroscopy (XANES), ground-state density functional theory (DFT), and transition dipole moment calculations are used to investigate the possibility that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Sm, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb and Lu) compounds represented molecular Ln II complexes. Results from the ground-state DFT calculations were supported by additional calculations that utilized complete-active-space multi-configuration approach with second-ordermore » perturbation theoretical correction (CASPT2). Through comparisons with standards, Ln(C 5H 4SiMe 3) 3 1– (Ln = Sm, Tm, Yb, Lu, Y) are determined to contain 4f 6 5d 0 (Sm II), 4f 13 5d 0 (Tm II), 4f 14 5d 0 (Yb II), 4f 14 5d 1 (Lu II), and 4d 1 (Y II) electronic configurations. Additionally, our results suggest that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Gd, Tb, Dy, Ho, and Er) also contain Ln II ions, but with 4f n 5d 1 configurations (not 4f n +1 5d 0). In these 4f n 5d 1 complexes, the C 3h-symmetric ligand environment provides a highly shielded 5d-orbital of a' symmetry that made the 4f n 5d 1 electronic configurations lower in energy than the more typical 4f n+1 5d 0 configuration.« less

  2. Evaluating the electronic structure of formal Ln II ions in Ln II(C 5H 4SiMe 3) 3 1– using XANES spectroscopy and DFT calculations

    DOE PAGES

    Fieser, Megan E.; Ferrier, Maryline Ghislaine; Su, Jing; ...

    2017-06-30

    Here, the isolation of [K(2.2.2-cryptand)][Ln(C 5H 4SiMe 3) 3], formally containing LnII, for all lanthanides (excluding Pm) was surprising given that +2 oxidation states are typically regarded as inaccessible for most 4f-elements. Herein, X-ray absorption near-edge spectroscopy (XANES), ground-state density functional theory (DFT), and transition dipole moment calculations are used to investigate the possibility that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Sm, Gd, Tb, Dy, Y, Ho, Er, Tm, Yb and Lu) compounds represented molecular Ln II complexes. Results from the ground-state DFT calculations were supported by additional calculations that utilized complete-active-space multi-configuration approach with second-ordermore » perturbation theoretical correction (CASPT2). Through comparisons with standards, Ln(C 5H 4SiMe 3) 3 1– (Ln = Sm, Tm, Yb, Lu, Y) are determined to contain 4f 6 5d 0 (Sm II), 4f 13 5d 0 (Tm II), 4f 14 5d 0 (Yb II), 4f 14 5d 1 (Lu II), and 4d 1 (Y II) electronic configurations. Additionally, our results suggest that Ln(C 5H 4SiMe 3) 3 1– (Ln = Pr, Nd, Gd, Tb, Dy, Ho, and Er) also contain Ln II ions, but with 4f n 5d 1 configurations (not 4f n +1 5d 0). In these 4f n 5d 1 complexes, the C 3h-symmetric ligand environment provides a highly shielded 5d-orbital of a' symmetry that made the 4f n 5d 1 electronic configurations lower in energy than the more typical 4f n+1 5d 0 configuration.« less

  3. Pharmacokinetics of 14 C-ortho-phenylphenol following intravenous administration in pigs.

    PubMed

    Nixon, Emma; Brooks, James D; Routh, Patricia A; Chittenden, Jason T; Baynes, Ronald E

    2017-04-01

    Workers in the USA are exposed to industrial formulations, which may be toxic. These formulations often contain preservatives or biocides such as ortho-phenylphenol (OPP). There are limited data describing OPP following intravenous administration to assess truly the clearance of this chemical in humans and other species. In vivo experiments were conducted in pigs to determine related pharmacokinetic parameters. 14 C-OPP was administered as an intravenous bolus dose. Blood, feces, urine and tissue samples were collected for analysis by liquid scintillation. Data were analyzed using non-compartmental and compartmental pharmacokinetic model approaches. These data fitted a three-compartment model and showed that the half-life of 14 C-OPP following the intravenous bolus in pigs was 46.26 ± 10.01 h. The kidneys play a crucial role in clearance of 14 C-OPP with a large percentage of the dose being found in the urine (70.3 ± 6.9% dose). Comparisons with other species suggest that 14 C-OPP clearance in pigs (2.48 ml h -1  kg -1 ) is less than that in humans (18.87 ml h -1  kg -1 ) and rats (35.51 ml h -1  kg -1 ). Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  4. Preparation of paper scintillator for detecting 3H contaminant.

    PubMed

    Miyoshi, Hirokazu; Ikeda, Toshiji

    2013-09-01

    Liquid scintillator (LS)-encapsulated silica was prepared by the sol-gel method and then was added dropwise onto a wipe paper to form a paper scintillator. First, the efficiencies of wipe were determined for both the paper scintillator and the wipe paper using a liquid scintillation counter (LSC). The efficiencies of wipe using the paper scintillator and the wipe paper were 88 and 36 %, respectively. The detection efficiencies were 5.5 % for the paper scintillator, 46 % for the wipe paper using an LS and 0.08 % for the (3)H/(14)C survey meter, respectively, compared with that of a melt-on scintillator of 47 %. Second, an (3)H contaminant on the paper scintillator was successfully detected using a photomultiplier without an LSC or an (3)H/(14)C survey meter. Finally, the paper scintillator was able to detect beta rays of the (3)H contaminant easily without an LS.

  5. 41 CFR 302-14.3 - Am I eligible to receive a home marketing incentive payment?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false Am I eligible to receive a home marketing incentive payment? 302-14.3 Section 302-14.3 Public Contracts and Property Management Federal Travel Regulation System RELOCATION ALLOWANCES RESIDENCE TRANSACTION ALLOWANCES 14-HOME...

  6. Bulk C, H, O, and fatty acid C stable isotope analyses for purity assessment of vegetable oils from the southern and northern hemispheres.

    PubMed

    Spangenberg, Jorge E

    2016-09-06

    |The carbon, hydrogen and oxygen stable isotope composition (δ 13 C, δ 2 H, and δ 18 O values) of plants and their products is linked to photosynthetic fractionation, environmental factors and agricultural practices. Therefore, they contribute to determining the purity of commercial vegetable oils and may provide information on their geographical origin. Maize, olive, sunflower, groundnut, soybean and rice oils differing in sites of growth in the southern and northern hemispheres were characterized by bulk oil stable isotope ratios (δ 13 C bulk , δ 2 H bulk , and δ 18 O bulk values), fatty acids (FAs) concentrations and δ 13 C FA values using elemental analysis/isotope ratio mass spectrometry, gas chromatography/mass spectrometry, gas chromatography/flame ionization detection and gas chromatography/combustion/isotope ratio mass spectrometry. Principal component analysis was applied to examine the inherent structure of the data. The δ 13 C bulk values of maize oils (-18.4 to -14.9 ‰) are typical for C 4 plants, and those of olive (-30.2 to -28.2 ‰), sunflower (-30.2 to -29.2 ‰), groundnut (-29.3 ‰), soybean (-30.6 ‰), and rice (-34.5 ‰) oils are typical for C 3 plants. The δ 2 H bulk values vary from -161 to -132‰ for maize oils and -171 to -109 ‰ for C 3 oils. The δ 18 O bulk values of all oils vary between 15.2 and 38.9 ‰. The major δ 13 C FA differences (>5 ‰) within plant species render the inter-C 3 -species comparison difficult. These differences are explained in terms of variations in the lipid biosynthetic pathways and blend of vegetable oils of different FA composition and δ 13 C FA values. The samples from the southern hemisphere are generally enriched in 13 C compared with those from the northern hemisphere. Differences between the southern and northern hemispheres were observed in δ 2 H (p < 0.001) and δ 18 O bulk (p = 0.129) values for all C 3 oils, and in δ 13 C 18:1 (p = 0.026) and δ 18 O bulk (p = 0

  7. Neuroprotective Effect of TAT-14-3-3ε Fusion Protein against Cerebral Ischemia/Reperfusion Injury in Rats

    PubMed Central

    Liu, Xiaoyan; Hu, Wenhui; Wang, Yinye

    2014-01-01

    Stroke is the major cause of death and disability worldwide, and the thrombolytic therapy currently available was unsatisfactory. 14-3-3ε is a well characterized member of 14-3-3 family, and has been reported to protect neurons against apoptosis in cerebral ischemia. However, it cannot transverse blood brain barrier (BBB) due to its large size. A protein transduction domain (PTD) of HIV TAT protein, is capable of delivering a large variety of proteins into the brain. In this study, we generated a fusion protein TAT-14-3-3ε, and evaluated its potential neuroprotective effect in rat focal ischemia/reperfusion (I/R) model. Western blot analysis validated the efficient transduction of TAT-14-3-3ε fusion protein into brain via a route of intravenous injection. TAT-14-3-3ε pre-treatment 2 h before ischemia significantly reduced cerebral infarction volume and improved neurologic score, while post-treatment 2 h after ischemia was less effective. Importantly, pre- or post-ischemic treatment with TAT-14-3-3ε significantly increased the number of surviving neurons as determined by Nissl staining, and attenuated I/R-induced neuronal apoptosis as showed by the decrease in apoptotic cell numbers and the inhibition of caspase-3 activity. Moreover, the introduction of 14-3-3ε into brain by TAT-mediated delivering reduced the formation of autophagosome, attenuated LC3B-II upregulation and reversed p62 downregulation induced by ischemic injury. Such inhibition of autophagy was reversed by treatment with an autophagy inducer rapamycin (RAP), which also attenuated the neuroprotective effect of TAT-14-3-3ε. Conversely, autophagy inhibitor 3-methyladenine (3-MA) inhibited I/R-induced the increase in autophagic activity, and attenuated I/R-induced brain infarct. These results suggest that TAT-14-3-3ε can be efficiently transduced into brain and exert significantly protective effect against brain ischemic injury through inhibiting neuronal apoptosis and autophagic activation. PMID

  8. Iodine-129 in snow and seawater in the Antarctic: level and source.

    PubMed

    Xing, Shan; Hou, Xiaolin; Aldahan, Ala; Possnert, Göran; Shi, Keliang; Yi, Peng; Zhou, Weijian

    2015-06-02

    Anthropogenic (129)I has been released to the environment in different ways and chemical species by human nuclear activities since the 1940s. These sources provide ideal tools to trace the dispersion of volatile pollutants in the atmosphere. Snow and seawater samples collected in Bellingshausen, Amundsen, and Ross Seas in Antarctica in 2011 were analyzed for (129)I and (127)I, including organic forms; it was observed that (129)I/(127)I atomic ratios in the Antarctic surface seawater ((6.1-13) × 10(-12)) are about 2 orders of magnitude lower than those in the Antarctic snow ((6.8-9.5) × 10(-10)), but 4-6 times higher than the prenuclear level (1.5 × 10(-12)), indicating a predominantly anthropogenic source of (129)I in the Antarctic environment. The (129)I level in snow in Antarctica is 2-4 orders of magnitude lower than that in the Northern Hemisphere, but is not significantly higher than that observed in other sites in the Southern Hemisphere. This feature indicates that (129)I in Antarctic snow mainly originates from atmospheric nuclear weapons testing from 1945 to 1980; resuspension and re-emission of the fallout (129)I in the Southern Hemisphere maintains the (129)I level in the Antarctic atmosphere. (129)I directly released to the atmosphere and re-emitted marine discharged (129)I from reprocessing plants in Europe might not significantly disperse to Antarctica.

  9. Rate Constant and RRKM Product Study for the Reaction Between CH3 and C2H3 at T = 298K

    NASA Technical Reports Server (NTRS)

    Thorn, R. Peyton, Jr.; Payne, Walter A., Jr.; Chillier, Xavier D. F.; Stief, Louis J.; Nesbitt, Fred L.; Tardy, D. C.

    2000-01-01

    The total rate constant k1 has been determined at P = 1 Torr nominal pressure (He) and at T = 298 K for the vinyl-methyl cross-radical reaction CH3 + C2H3 yields products. The measurements were performed in a discharge flow system coupled with collision-free sampling to a mass spectrometer operated at low electron energies. Vinyl and methyl radicals were generated by the reactions of F with C2H4 and CH4, respectively. The kinetic studies were performed by monitoring the decay of C2H3 with methyl in excess, 6 < |CH3|(sub 0)/|C2H3|(sub 0) < 21. The overall rate coefficient was determined to be k1(298 K) = (1.02 +/- 0.53)x10(exp -10) cubic cm/molecule/s with the quoted uncertainty representing total errors. Numerical modeling was required to correct for secondary vinyl consumption by reactions such as C2H3 + H and C2H3 + C2H3. The present result for k1 at T = 298 K is compared to two previous studies at high pressure (100-300 Torr He) and to a very recent study at low pressure (0.9-3.7 Torr He). Comparison is also made with the rate constant for the similar reaction CH3 + C2H5 and with a value for k1 estimated by the geometric mean rule employing values for k(CH3 + CH3) and k(C2H3 + C2H3). Qualitative product studies at T = 298 K and 200 K indicated formation of C3H6, C2H2, and C2H5 as products of the combination-stabilization, disproportionation, and combination-decomposition channels, respectively, of the CH3 + C2H3 reaction. We also observed the secondary C4H8 product of the subsequent reaction of C3H5 with excess CH3; this observation provides convincing evidence for the combination-decomposition channel yielding C3H5 + H. RRKM calculations with helium as the deactivator support the present and very recent experimental observations that allylic C-H bond rupture is an important path in the combination reaction. The pressure and temperature dependencies of the branching fractions are also predicted.

  10. The DNA cytosine deaminase APOBEC3H haplotype I likely contributes to breast and lung cancer mutagenesis.

    PubMed

    Starrett, Gabriel J; Luengas, Elizabeth M; McCann, Jennifer L; Ebrahimi, Diako; Temiz, Nuri A; Love, Robin P; Feng, Yuqing; Adolph, Madison B; Chelico, Linda; Law, Emily K; Carpenter, Michael A; Harris, Reuben S

    2016-09-21

    Cytosine mutations within TCA/T motifs are common in cancer. A likely cause is the DNA cytosine deaminase APOBEC3B (A3B). However, A3B-null breast tumours still have this mutational bias. Here we show that APOBEC3H haplotype I (A3H-I) provides a likely solution to this paradox. A3B-null tumours with this mutational bias have at least one copy of A3H-I despite little genetic linkage between these genes. Although deemed inactive previously, A3H-I has robust activity in biochemical and cellular assays, similar to A3H-II after compensation for lower protein expression levels. Gly105 in A3H-I (versus Arg105 in A3H-II) results in lower protein expression levels and increased nuclear localization, providing a mechanism for accessing genomic DNA. A3H-I also associates with clonal TCA/T-biased mutations in lung adenocarcinoma suggesting this enzyme makes broader contributions to cancer mutagenesis. These studies combine to suggest that A3B and A3H-I, together, explain the bulk of 'APOBEC signature' mutations in cancer.

  11. 17 CFR 240.3a12-11 - Exemption from sections 8(a), 14(a), 14(b), and 14(c) for debt securities listed on a national...

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...), 14(a), 14(b), and 14(c) for debt securities listed on a national securities exchange. 240.3a12-11... 14(c) for debt securities listed on a national securities exchange. (a) Debt securities that are listed for trading on a national securities exchange shall be exempt from the restrictions on borrowing...

  12. Crystal structure of (E)-2-[(2-bromopyridin-3-yl)methyl-idene]-6-meth-oxy-3,4-di-hydro-naphthalen-1(2H)-one and 3-[(E)-(6-meth-oxy-1-oxo-1,2,3,4-tetra-hydro-naphthalen-2-ylidene)meth-yl]pyridin-2(1H)-one.

    PubMed

    Zingales, Sarah K; Moore, Morgan E; Goetz, Andrew D; Padgett, Clifford W

    2016-07-01

    The title compounds C17H14BrNO2, (I), and C17H15NO3, (II), were obtained from the reaction of 6-meth-oxy-3,4-di-hydro-2H-naphthalen-1-one and 2-bromo-nicotinaldehyde in ethanol. Compound (I) was the expected product and compound (II) was the oxidation product from air exposure. In the crystal structure of compound (I), there are no short contacts or hydrogen bonds. The structure does display π-π inter-actions between adjacent benzene rings and adjacent pyridyl rings. Compound (II) contains two independent mol-ecules, A and B, in the asymmetric unit; both are non-planar, the dihedral angles between the meth-oxy-benzene and 1H-pyridin-2-one mean planes being 35.07 (9)° in A and 35.28 (9)°in B. In each mol-ecule, the 1H-pyridin-2-one unit participates in inter-molecular N-H⋯O hydrogen bonding to another mol-ecule of the same type (A to A or B to B). The structure also displays π-π inter-actions between the pyridyl and the benzene rings of non-equivalent mol-ecules (viz., A to B and B to A).

  13. C Chondrite Clasts in H Chondrite Regolith Breccias: Something Different

    NASA Technical Reports Server (NTRS)

    Zolensky, M. E.; Fries, M.; Utas, J.; Chan, Q. H.-S.; Kebukawa, Y.; Steele, A.; Bodnar, R. J.; Ito, M.; Nakashima, D.; Greenwood, R.; hide

    2016-01-01

    Zag (H3-6) and Monahans (1998) (H5) are regolith breccias that contain 4.5 GY old halite crystals which in turn contain abundant inclusions of aqueous fluids, solids and organics [1-4]. We have previously proposed that these halites originated on a hydro-volcanically-active C-class asteroid, probably Ceres [3-7]. We have begun a detailed analysis of the included solids and organics and are re-examining the related carbonaceous (C)) chondrite clast we previously reported in Zag [5-7]. These new investigations will potentially reveal the mineralogy of asteroid Ceres. We report here on potentially identical C chondrite clasts in the H chondrite regolith breccias Tsukuba (H5-6) and Carancas (H4-5). The clast in Tsukuba was known before [8], but the Carancas clast is newly recognized.

  14. Synthesis and reactivity of dimeric Ar'TlTlAr' and trimeric (Ar"T1)3 (Ar', Ar" = bulky terphenyl group) thallium(I) derivatives: Tl(I)-Tl(I) bonding in species ligated by monodentate ligands.

    PubMed

    Wright, Robert J; Phillips, Andrew D; Hino, Shirley; Power, Philip P

    2005-04-06

    The synthesis and characterization of three new organothallium(I) compounds are reported. Reaction of (Ar'Li)(2) (Ar' = C(6)H(3)-2,6-(C(6)H(3)-2,6-Pr(i)(2))(2)) and Ar"Li (Ar" = C(6)H(3)-2,6-(C(6)H(3)-2,6-Me(2))(2)) with TlCl in Et(2)O afforded (Ar'Tl)(2) (1) and (Ar' 'Tl)(3) (2). The "dithallene" 1 is the heaviest group 13 dimetallene and features a planar, trans-bent structure with Ar'Tl-Tl = 119.74(14) degrees and Tl-Tl = 3.0936(8) A. Compound 2 is the first structurally characterized neutral, three-membered ring species of formula c-(MR)(3) (M = Al-Tl; R = organo group). The Tl(3) ring has Tl-Tl distances in the range ca. 3.21-3.37 A as well as pyramidal Tl geometries. The Tl-Tl bonds in 1 and 2 are outside the range (2.88-2.97 A) of Tl-Tl single bonds in R(2)TlTlR(2) compounds. The weak Tl-Tl bonding in 1 and 2 leads to their dissociation into Ar'Tl and Ar' 'Tl monomers in hexane. The Ar'Tl monomer behaves as a Lewis base and readily forms a 1:1 donor-acceptor complex with B(C(6)F(5))(3) to give Ar'TlB(C(6)F(5))(3), 3. Adduct 3 features an almost linear thallium C(ipso)-Tl-B angle of 174.358(7) degrees and a Tl-B distance of 2.311(2) A, which indicates strong association. Treatment of 1 with a variety of reagents resulted in no reactions. The lower reactivity of 1 is in accord with the reluctance of Tl(I) to undergo oxidation to Tl(III) due to the unreactive character of the 6s(2) electrons.

  15. Homooligomeric β3 (R)-valine peptides: Transformation between C14 and C12 helical structures induced by a guest Aib residue.

    PubMed

    Vasantha, Basavalingappa; George, Gijo; Raghothama, Srinivasarao; Balaram, Padmanabhan

    2017-01-01

    Novel helical, structures unprecedented in the chemistry of α-polypeptides, may be found in polypeptides containing β and γ amino acids. The structural characterization of C 12 and C 14 -helices in oligo β-peptides was originally achieved using conformationally constrained cyclic β-residues. This study explores the conformational characteristics of proteinogenic β 3 residues in homooligomeric sequences and addresses the issue of inducing a transition between C 14 and C 12 helices by the introduction of a guest α-residue. Folded C 14 -helical structures are demonstrated for the nonapeptide Boc-[β 3 (R)Val] 9 -OMe by NMR methods in CDCl 3 -DMSO mixtures, while the peptide was found to be aggregated in CDCl 3 . The insertion of a guest Aib residue into an oligo-β-valine sequence in the octapeptide model Boc-[(β 3 (R)Val) 3 -Aib-(β 3 (R)Val] 4 -OMe results in well dispersed NH region in the NMR spectrum indicating folded structures in CDCl 3 . Structure calculations for both the peptides using NOE distance constraints support a C 14 helical structure in the homooligomer which transform into a C 12 helix on introduction of the guest Aib residue. © 2016 Wiley Periodicals, Inc.

  16. Basic surface-active properties in the homologous series of β-alkyl (C12H25/C18H37) polyethyleneoxy (n = 0-20) propionamides

    PubMed Central

    2013-01-01

    Background Heterogeneous β-Alkyl (C12H25/C18H37) polyethyleneoxy (n = 0-20) propionamides [R(EO)nPD] represent new “hybrid” nonionic-ionic colloidal structures in the field of surface-active products (technical products). These “niche” compounds have three structural and compositional characteristics that also define their basic colloidal properties: mixture of R and PEO chain homologues; specific conformations due to the PEO chains; and the presence of side products from the addition of higher alcohols, polyethyleneglycols and traces of water to acrylamide. The proposed major objective of this paper is the basic informative colloidal characterization (functional classification, HLB balance, surface tension, critical micelle concentration) in direct correlation with the structural changes in the homologous series of LM(EO)nPD and CS(EO)nPD. The structures were obtained either indirectly by cyanoethylation followed by partial acid hydrolysis of the corresponding β-propionitriles, or directly by the nucleophilic addition under alkaline catalysis of linear higher alcohols C12H25/C14H29 (7/3) (LM) and C16H33/C18H37 (CS) as such and heterogeneous polyethoxylated (n = 3-20) to acrylamide monomer, through an adapted classic reaction scheme. Results In the series of basic colloidal characteristics investigated the structure-surface activity dependence is confirmed. Their indicative character for R(EO)nPD is based on the assumption that the structures studied are not unitary (heterogeneous) because: a) the hydrophobic chains C12H25/C18H37 have been grouped in two variants, C12H25/C14H29 (LM); C16H33/C18H37 (CS), each with an internal mass ratio of 7/3; b) the hydrophilic polyoxyethylene chains (n = 3-20) have polydisperse character; the meaning and value the oligomerization degree, n, is that of weighted average. In these conditions the surface tension increases proportionally with the oligomerization degree of the polyoxyethylene chain, while the

  17. Synthesis of 6-amino-5-cyano-1,4-disubstituted-2(1H)-pyrimidinones via copper-(I)-catalyzed alkyne-azide 'click chemistry' and their reactivity.

    PubMed

    Najahi, Ennaji; Sudor, Jan; Chabchoub, Fakher; Nepveu, Françoise; Zribi, Fethi; Duval, Romain

    2010-12-03

    In this paper we present the room temperature synthesis of a novel serie of 1,4-disubstituted-1,2,3-triazoles 4a-l by employing the (3+2) cycloaddition reaction of pyrimidinones containing alkyne functions with different model azides in the presence of copper sulphate and sodium ascorbate. To obtain the final triazoles, we also synthesized the major precursors 6-amino-5-cyano-1,4-disubstituted-2(1H)-pyrimidinones 3a-r from ethyl 2,2-dicyanovinylcarbamate derivatives 2a-c and various primary aromatic amines containing an alkyne group. The triazoles were prepared in good to very good yields.

  18. Regioselective Cu(I)-catalyzed tandem A3-coupling/decarboxylative coupling to 3-amino-1,4-enynes.

    PubMed

    Feng, Huangdi; Ermolat'ev, Denis S; Song, Gonghua; Van der Eycken, Erik V

    2012-04-06

    An efficient and novel copper-mediated protocol for the synthesis of 3-amino-1,4-enynes from glyoxylic acid, an amine, and an alkyne was developed. This new reaction involving two sequential C-C bond formations is air and moisture tolerant and proceeds via a tandem A(3)-coupling and a selective decarboxylative coupling.

  19. Rhombohedral <i>R3c> to orthorhombic <i>Pnma> phase transition induced by Y-doping in BiFeO3.

    PubMed

    Graf, Monica Elisabet; Di Napoli, Solange; Barral, Maria Andrea Andrea; Saleh Medina, Leila; Negri, R Martín; Sepliarsky, Marcelo; Llois, Ana María

    2018-05-23

    In this work we study, by means of <i>ab initio</i> calculations, the structural, electronic and magnetic properties of Y-doped BiFeO<sub>3</sub> compounds. We determine that there is a morphotropic phase boundary at an yttrium concentration of (18 ± 2)%, where the structure changes from <i>R3c</i> to <i>Pnma</i>. This structural transition is driven by the chemical pressure induced by the dopant. By analyzing the evolution of the oxygen octahedral tilts we find an enhanced antiferrodistortive distortion when increasing the Y-doping, together with a reduction of the ferroelectric distorsion, that gives rise to a smaller value of the electric polarization. These cooperative effects should lead to a larger canting of the Fe magnetic moments and to a larger ferromagnetic response in the <i>R3c</i> phase, as it is observed in the experiments. . © 2018 IOP Publishing Ltd.

  20. Crystal structure of poly[N,N-diethyl-2-hy-droxy-ethan-1-aminium [μ3-cyanido-κ(3) C:C:N-di-μ-cyanido-κ(4) C:N-dicuprate(I)

    PubMed

    Corfield, Peter W R; Cleary, Emma; Michalski, Joseph F

    2016-07-01

    In the title compound, {(C6H16NO)[Cu2(CN)3]} n , the cyanide groups link the Cu(I) atoms into an open three-dimensional anionic network, with the mol-ecular formula Cu2(CN)3 (-). One Cu(I) atom is tetra-hedrally bound to four CN groups, and the other Cu(I) atom is bonded to three CN groups in an approximate trigonal-planar coordination. The tetra-hedrally coordinated Cu(I) atoms are linked into centrosymmetric dimers by the C atoms of two end-on bridging CN groups which bring the Cu(I) atoms into close contact at 2.5171 (7) Å. Two of the cyanide groups bonded to the Cu(I) atoms with trigonal-planar surrounding link the dimeric units into columns along the a axis, and the third links the columns together to form the network. The N,N-di-ethyl-ethano-lamine mol-ecules used in the synthesis have become protonated at the N atoms and are situated in cavities in the network, providing charge neutrality, with no covalent inter-actions between the cations and the anionic network.

  1. Effects of Enrichment and Litter Parity on Reproductive Performance and Behavior in BALB/c and 129/Sv Mice.

    PubMed

    Whitaker, Julia W; Moy, Sheryl S; Pritchett-Corning, Kathleen R; Fletcher, Craig A

    2016-01-01

    We examined the effect of adding species-appropriate environmental enrichment items to breeding cages of BALB/cAnNCrl and 129S2/SvPasCrl mice. The 3 enrichment conditions were: 1) cotton nesting material; 2) nesting material plus a paper shelter and rolled paper bedding; and 3) an igloo dome with an exercise wheel in addition to the shelter-group enrichments. We measured litter size, litter survival to weaning age, average pup weight at 21 d, and the interlitter interval to evaluate reproductive performance. A random subset of the first- or second-litter offspring from each enrichment condition and strain was assessed in multiple behavioral tests. Enrichment significantly affected anxiety-like behavior and sociability, with the direction of change dependent on strain and sex. Litter parity had greater effects on some reproductive parameters than did the enrichment condition, and this effect was not solely due to a difference between the first compared with subsequent litters. The significant effects of litter parity on the number of pups born and weaned, female pup weight, and interlitter interval were dependent on the enrichment condition in BALB/c but not 129/Sv mice. Offspring from the first or second litter were included in a generational component to investigate whether enrichment effects on reproduction persist in adult offspring after transfer to a different facility for breeding. Natal cage enrichment had no effect on any reproductive parameter in the transferred mice. Overall, additional enrichment beyond nesting material had a beneficial effect on the interlitter interval in BALB/c mice and on the number of pups weaned in 129/Sv mice.

  2. Effects of Enrichment and Litter Parity on Reproductive Performance and Behavior in BALB/c and 129/Sv Mice

    PubMed Central

    Whitaker, Julia W; Moy, Sheryl S; Pritchett-Corning, Kathleen R; Fletcher, Craig A

    2016-01-01

    We examined the effect of adding species-appropriate environmental enrichment items to breeding cages of BALB/cAnNCrl and 129S2/SvPasCrl mice. The 3 enrichment conditions were: 1) cotton nesting material; 2) nesting material plus a paper shelter and rolled paper bedding; and 3) an igloo dome with an exercise wheel in addition to the shelter-group enrichments. We measured litter size, litter survival to weaning age, average pup weight at 21 d, and the interlitter interval to evaluate reproductive performance. A random subset of the first- or second-litter offspring from each enrichment condition and strain was assessed in multiple behavioral tests. Enrichment significantly affected anxiety-like behavior and sociability, with the direction of change dependent on strain and sex. Litter parity had greater effects on some reproductive parameters than did the enrichment condition, and this effect was not solely due to a difference between the first compared with subsequent litters. The significant effects of litter parity on the number of pups born and weaned, female pup weight, and interlitter interval were dependent on the enrichment condition in BALB/c but not 129/Sv mice. Offspring from the first or second litter were included in a generational component to investigate whether enrichment effects on reproduction persist in adult offspring after transfer to a different facility for breeding. Natal cage enrichment had no effect on any reproductive parameter in the transferred mice. Overall, additional enrichment beyond nesting material had a beneficial effect on the interlitter interval in BALB/c mice and on the number of pups weaned in 129/Sv mice. PMID:27423144

  3. The Production of Polycyclic Aromatic Hydrocarbon Anions in Inert Gas Matrices Doped with Alkali Metals. Electronic Absorption Spectra of the Pentacene Anion (C22H14(-))

    NASA Technical Reports Server (NTRS)

    Halasinski, Thomas M.; Hudgins, Douglas M.; Salama, Farid; Allamandola, Louis J.; Mead, Susan (Technical Monitor)

    1999-01-01

    The absorption spectra of pentacene (C22H14) and its radical cation (C22H14(+)) and anion (C22H14(-)) isolated in inert-gas matrices of Ne, Ar, and Kr are reported from the ultraviolet to the near-infrared. The associated vibronic band systems and their spectroscopic assignments are discussed together with the physical and chemical conditions governing ion (and counterion) production in the solid matrix. In particular, the formation of isolated pentacene anions is found to be optimized in matrices doped with alkali metal (Na and K).

  4. GENETIC BACKGROUND, GENDER, AGE, BODY TEMPERATURE, AND ARTERIAL BLOOD pH HAVE A MAJOR IMPACT ON MYOCARDIAL INFARCT SIZE IN THE MOUSE AND NEED TO BE CAREFULLY MEASURED AND/OR TAKEN INTO ACCOUNT: RESULTS OF A COMPREHENSIVE ANALYSIS OF DETERMINANTS OF INFARCT SIZE IN 1074 MICE

    PubMed Central

    Guo, Yiru; Flaherty, Michael P.; Wu, Wen-Jian; Tan, Wei; Zhu, Xiaoping; Li, Qianhong; Bolli, Roberto

    2013-01-01

    To determine whether the myocardial response to ischemia/reperfusion (I/R) injury varies depending on genetic background, gender, age, body temperature, and arterial blood pH, we studied 1074 mice from 19 strains (including 129S6/SvEvTac (129S6), B6/129P2-Ptgs2tm1Unc, B6/129SvF2/J, B6/129/D2, B6/CBAF1, B6/DBA/1JNcr, BALB/c, BPH2/J, C57BL/6/J (B6/J), C3H/DBA, C3H/FB/FF, C3H/HeJ-Pde6brd1, FVB/N/J [FVB/N], FVB/B6, FVB/ICR and Crl:ICR/H [ICR]) and distributed them into 69 groups depending on strain and: (i) two phases of ischemic preconditioning (PC); (ii) coronary artery occlusion (O) time; (iii) gender; (iv) age; (v) blood transfusion; (vi) core body temperature; and (vii) arterial blood pH. Mice underwent O either without (non-preconditioned [naïve]) or with prior cyclic O/reperfusion (R) (PC stimulus) consisting of six 4-min O/4-min R cycles 10 min (early PC, EPC) or 24 h (late PC, LPC) prior to 30 or 45-min O and 24 h R. In B6/J and B6/129/D2 mice, almost the entire risk region was infarcted after a 60-min O. Of the naïve mouse hearts, B6/ecSODWT and FVB/N mice had infarct sizes significantly smaller than those of the other mice. All strains except FVB/N benefited from the cardioprotection afforded by the early phase of PC; in contrast, development of LPC was inconsistent amongst groups and was strain-dependent. Female gender (i) was associated with reduced infarct size in ICR mice, (ii) determined whether LPC developed in ICR mice, and (iii) limited the protection afforded by EPC in 129S6 mice. Importantly, mild hypothermia (1 °C decrease in core temperature) and mild acidosis (0.18 decrease in blood pH) resulted in a striking cardioprotective effect in ICR mice: 67.5% and 43.0% decrease in infarct size, respectively. Replacing blood losses with crystalloid fluids (instead of blood) during surgery also reduced infarct size. To our knowledge, this is the largest analysis of the determinants of infarct size in mice ever published. The results demonstrate that

  5. Photochemical Carboxylation of Activated C(sp3 )-H Bonds with CO2.

    PubMed

    Gui, Yong-Yuan; Zhou, Wen-Jun; Ye, Jian-Heng; Yu, Da-Gang

    2017-04-10

    From ugly duckling to beautiful C1: Although CO 2 may represent an ideal C1 source, it is challenging to use it as a raw material and direct carboxylation with CO 2 has mainly been confined to highly reactive species. However, recent significant breakthroughs have been made in photochemical carboxylation of challenging, un-acidic, C(sp 3 )-H bonds, including benzylic, allylic and amine C-H bonds. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. Changing concentrations of CO, CH(4), C(5)H(8), CH(3)Br, CH(3)I, and dimethyl sulfide during the Southern Ocean Iron Enrichment Experiments.

    PubMed

    Wingenter, Oliver W; Haase, Karl B; Strutton, Peter; Friederich, Gernot; Meinardi, Simone; Blake, Donald R; Rowland, F Sherwood

    2004-06-08

    Oceanic iron (Fe) fertilization experiments have advanced the understanding of how Fe regulates biological productivity and air-sea carbon dioxide (CO(2)) exchange. However, little is known about the production and consumption of halocarbons and other gases as a result of Fe addition. Besides metabolizing inorganic carbon, marine microorganisms produce and consume many other trace gases. Several of these gases, which individually impact global climate, stratospheric ozone concentration, or local photochemistry, have not been previously quantified during an Fe-enrichment experiment. We describe results for selected dissolved trace gases including methane (CH(4)), isoprene (C(5)H(8)), methyl bromide (CH(3)Br), dimethyl sulfide, and oxygen (O(2)), which increased subsequent to Fe fertilization, and the associated decreases in concentrations of carbon monoxide (CO), methyl iodide (CH(3)I), and CO(2) observed during the Southern Ocean Iron Enrichment Experiments.

  7. Iodine-129 and iodine-127 speciation in groundwater at the Hanford site, US: iodate incorporation into calcite.

    PubMed

    Zhang, Saijin; Xu, Chen; Creeley, Danielle; Ho, Yi-Fang; Li, Hsiu-Ping; Grandbois, Russell; Schwehr, Kathleen A; Kaplan, Daniel I; Yeager, Chris M; Wellman, Dawn; Santschi, Peter H

    2013-09-03

    The geochemical transport and fate of radioiodine depends largely on its chemical speciation that is greatly affected by environmental factors. This study reports, for the first time, the speciation of stable and radioactive iodine in the groundwater from the Hanford Site. Iodate was the dominant species and accounted for up to 84% of the total iodine present. The alkaline pH (pH ∼ 8) and predominantly oxidizing environment may have prevented reduction of the iodate. In addition, groundwater samples were found to have large amounts of calcite precipitate which were likely formed as a result of CO2 degassing during removal from the deep subsurface (>70m depth). Further analyses indicated that between 7 and 40% of the dissolved (127)I and (129)I that was originally in the groundwater had coprecipitated in the calcite. Iodate was the main species incorporated into calcite and this incorporation process could be impeded by elevating the pH and decreasing ionic strength in groundwater. This study provides critical information for predicting the long-term fate and transport of (129)I. Furthermore, the common sampling artifact resulting in the precipitation of calcite by degassing CO2, had the unintended consequence of providing insight into a potential solution for the in situ remediation of groundwater (129)I.

  8. The molecular core in G34.3 + 0.2 - Millimeter interferometric observations of HCO(+), H(C-13)N, H(C-15)N, and SO

    NASA Technical Reports Server (NTRS)

    Carral, Patricia; Welch, William J.

    1992-01-01

    This study presents high-resolution observations of the molecular core in the star-forming region G34.3 + 0.2. Maps at 6-arcsec resolution of emission and absorption of the J = 1 - 0 transitions of HCO(+), H (C-13)N, H(C-15)N, and of the 2(2) - 1(1) transition of SO were obtained in addition to a map of the 3.4-mm continuum emission from the compact H II component. The HCL(+) emission toward G34.3 + 0.2 traces a warm molecular core about 0.9 pc in size. Emission from H (C-13)N is detected over about 0.3 pc. The cometary H II region lies near the edge of the molecular core. The blueshift of the radio recombination lines with respect to the molecular emission suggests that gas from the H II region is accelerated in a champagne flow caused by a steep gradient in the ambient gas density.

  9. A new mutation, gld, that produces lymphoproliferation and autoimmunity in C3H/HeJ mice.

    PubMed

    Roths, J B; Murphy, E D; Eicher, E M

    1984-01-01

    A newly discovered autosomal recessive mutation, generalized lymphoproliferative disease (gld), in the C3H/HeJ strain of mice, determines the development of early onset massive lymphoid hyperplasia with autoimmunity. Significant lymph node enlargement is apparent as early as 12 wk of age. By 20 wk, lymph nodes are 50-fold heavier than those of coisogenic C3H/HeJ-+/+ mice. There is a concomitant increase in the numbers of peripheral blood lymphocytes. Analysis of C3H-gld lymph node lymphocyte subsets by immunofluorescence indicates an increase in numbers of B cells, T cells, and null (Thy-1-, sIg-) lymphocytes by 6-, 15-, and 33-fold compared with congeneic control mice. Serologically, gld/gld mice develop antinuclear antibodies (including anti-dsDNA), thymocyte-binding autoantibody, and hypergammaglobulinemia with major increases in several immunoglobulin isotypes. Mutant gld mice live only one-half as long as normal controls (12 and 23 mo, respectively). Interstitial pneumonitis was found in virtually all C3H-gld mice autopsied when moribund. Although immune complexes were detected in the glomerulus by immunofluorescence techniques, only 14% of the autopsied mice had significant lupus-like nephritis. Vascular disease was not found. The pattern of early onset massive lymph node enlargement, hypergammaglobulinemia, and production of antinuclear autoantibodies resembles the basic abnormal phenotype induced by the lpr (lymphoproliferation) mutation. The mutations gld and lpr are not allelic. Linkage studies indicate that gld is located between Pep-3 and Lp on chromosome 1. This new mutation adds another genetically well-defined model to the list of murine lymphoproliferative/autoimmune disorders that may be exploited to gain a clearer understanding of immunoregulatory defects and for identifying common pathogenetic factors involved in systemic autoimmune diseases.

  10. A new mutation, gld, that produces lymphoproliferation and autoimmunity in C3H/HeJ mice

    PubMed Central

    1984-01-01

    A newly discovered autosomal recessive mutation, generalized lymphoproliferative disease (gld), in the C3H/HeJ strain of mice, determines the development of early onset massive lymphoid hyperplasia with autoimmunity. Significant lymph node enlargement is apparent as early as 12 wk of age. By 20 wk, lymph nodes are 50-fold heavier than those of coisogenic C3H/HeJ-+/+ mice. There is a concomitant increase in the numbers of peripheral blood lymphocytes. Analysis of C3H-gld lymph node lymphocyte subsets by immunofluorescence indicates an increase in numbers of B cells, T cells, and null (Thy-1-, sIg-) lymphocytes by 6-, 15-, and 33-fold compared with congeneic control mice. Serologically, gld/gld mice develop antinuclear antibodies (including anti-dsDNA), thymocyte-binding autoantibody, and hypergammaglobulinemia with major increases in several immunoglobulin isotypes. Mutant gld mice live only one-half as long as normal controls (12 and 23 mo, respectively). Interstitial pneumonitis was found in virtually all C3H-gld mice autopsied when moribund. Although immune complexes were detected in the glomerulus by immunofluorescence techniques, only 14% of the autopsied mice had significant lupus-like nephritis. Vascular disease was not found. The pattern of early onset massive lymph node enlargement, hypergammaglobulinemia, and production of antinuclear autoantibodies resembles the basic abnormal phenotype induced by the lpr (lymphoproliferation) mutation. The mutations gld and lpr are not allelic. Linkage studies indicate that gld is located between Pep-3 and Lp on chromosome 1. This new mutation adds another genetically well-defined model to the list of murine lymphoproliferative/autoimmune disorders that may be exploited to gain a clearer understanding of immunoregulatory defects and for identifying common pathogenetic factors involved in systemic autoimmune diseases. PMID:6693832

  11. Relative quantum yield of I-asterisk(2P1/2) in the tunable laser UV photodissociation of i-C3F7I and n-C3F7I - Effect of temperature and exciplex emission

    NASA Technical Reports Server (NTRS)

    Smedley, J. E.; Leone, S. R.

    1983-01-01

    Wavelength-specific relative quantum yields of metastable I from pulsed laser photodissociation of i-C3F7I and n-C3F7I in the range 265-336 nm are determined by measuring the time-resolved infrared emission from the atomic I(P-2(1/2) P-2(3/2) transition. It is shown that although this yield appears to be unity from 265 to 298 nm, it decreases dramatically at longer wavelengths. Values are also reported for the enhancement of emission from metastable I due to exciplex formation at several temperatures. The exciplex formation emission increases linearly with parent gas pressure, but decreases with increasing temperature. Absorption spectra of i- and n-C3F7I between 303 and 497 K are presented, and the effect of temperature on the quantum yields at selected wavelengths greater than 300 nm, where increasing the temperature enhances the absorption considerably, are given. The results are discussed in regard to the development of solar-pumped iodine lasers.

  12. A Layered Solution Crystal Growth Technique and the Crystal Structure of (C 6H 5C 2H 4NH 3) 2PbCl 4

    NASA Astrophysics Data System (ADS)

    Mitzi, D. B.

    1999-07-01

    Single crystals of the organic-inorganic perovskite (C6H5C2H4NH3)2PbCl4 have been grown at room temperature using a layered solution approach. The bottom solution layer, contained within a long straight tube, consists of PbCl2 dissolved in concentrated aqueous HCl. A less dense layer of methanol is carefully placed on top of the HCl/PbCl2 solution using a syringe. Finally, a stoichiometric quantity of C6H5C2H4NH2 (relative to the PbCl2) is added to the top of the column. As the layers slowly diffuse together, well-formed crystals of (C6H5C2H4NH3)2PbCl4 appear near the interface between the HCl/PbCl2 and C6H5C2H4NH2 solutions. The thick, plate-like crystals are well suited for X-ray crystallography studies. Room temperature intensity data were refined using a triclinic (Poverline1) cell (a=11.1463(3) Å, b=11.2181(3) Å, c=17.6966(5) Å, α= 99.173(1)°, β=104.634(1)°, γ=89.999(1)°, V=2111.8(1) Å3, Z=4, Rf/Rw=0.031/0.044). The organic-inorganic layered perovskite structure features well-ordered sheets of corner-sharing distorted PbCl6 octahedra separated by bilayers of phenethylammonium cations. Tilting and rotation of the PbCl6 octahedra within the perovskite sheets, coupled with organic cation ordering, leads to the unusual in-sheet 2ap×2ap superstructure, where ap is the lattice constant for the ideal cubic perovskite.

  13. Effects of microRNA-129 and its target gene c-Fos on proliferation and apoptosis of hippocampal neurons in rats with epilepsy via the MAPK signaling pathway.

    PubMed

    Wu, Dong-Mei; Zhang, Yu-Tong; Lu, Jun; Zheng, Yuan-Lin

    2018-09-01

    This study aims to investigate the effect of microRNA-129 (miR-129) on proliferation and apoptosis of hippocampal neurons in epilepsy rats by targeting c-Fos via the MAPK signaling pathway. Thirty rats were equally classified into a model group (successfully established as chronic epilepsy models) and a normal group. Expression of miR-129, c-Fos, bax, and MAPK was detected by RT-qPCR and Western blotting. Hippocampal neurons were assigned into normal, blank, negative control (NC), miR-129 mimic, miR-129 inhibitor, siRNA-c-Fos, miR-129 inhibitor+siRNA-c-Fos groups. The targeting relationship between miR-129 and c-Fos was predicted and verified by bioinformatics websites and dual-luciferase reporter gene assay. Cell proliferation after transfection was measured by MTT assay, and cell cycle and apoptosis by flow cytometry. c-Fos is a potential target gene of miR-129. Compared with the normal group, the other six groups showed a decreased miR-129 expression; increased expression of expression of c-Fos, Bax, and MAPK; decreased proliferation; accelerated apoptosis; more cells arrested in the G1 phase; and fewer cells arrested in the S phase. Compared with the blank and NC groups, the miR-129 mimic group and the siRNA-c-Fos group showed decreased expression of c-Fos, Bax, and MAPK, increased cells proliferation, and decreased cell apoptosis, fewer cells arrested in the G1 phase and more cells arrested in the S phase. However, the miR-129 inhibitor groups showed reverse consequences. This study suggests that miR-129 could inhibit the occurrence and development of epilepsy by repressing c-Fos expression through inhibiting the MAPK signaling pathway. © 2017 Wiley Periodicals, Inc.

  14. Unique structure of iC3b resolved at a resolution of 24 Å by 3D-electron microscopy.

    PubMed

    Alcorlo, Martin; Martínez-Barricarte, Ruben; Fernández, Francisco J; Rodríguez-Gallego, César; Round, Adam; Vega, M Cristina; Harris, Claire L; de Cordoba, Santiago Rodríguez; Llorca, Oscar

    2011-08-09

    Activation of C3, deposition of C3b on the target surface, and subsequent amplification by formation of a C3-cleaving enzyme (C3-convertase; C3bBb) triggers the effector functions of complement that result in inflammation and cell lysis. Concurrently, surface-bound C3b is proteolyzed to iC3b by factor I and appropriate cofactors. iC3b then interacts with the complement receptors (CR) of the Ig superfamily, CR2 (CD21), CR3 (CD11b/CD18), and CR4 (CD11c/CD18) on leukocytes, down-modulating inflammation, enhancing B cell-mediated immunity, and targeting pathogens for clearance by phagocytosis. Using EM and small-angle X-ray scattering, we now present a medium-resolution structure of iC3b (24 Å). iC3b displays a unique conformation with structural features distinct from any other C3 fragment. The macroglobulin ring in iC3b is similar to that in C3b, whereas the TED (thioester-containing domain) domain and the remnants of the CUB (complement protein subcomponents C1r/C1s, urchin embryonic growth factor and bone morphogenetic protein 1) domain have moved to locations more similar to where they were in native C3. A consequence of this large conformational change is the disruption of the factor B binding site, which renders iC3b unable to assemble a C3-convertase. This structural model also justifies the decreased interaction between iC3b and complement regulators and the recognition of iC3b by the CR of the Ig superfamily, CR2, CR3, and CR4. These data further illustrate the extraordinary conformational versatility of C3 to accommodate a great diversity of functional activities.

  15. Interactions of ( sup 3 H)amphetamine with rat brain synaptosomes. I. Saturable sequestration

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

    Zaczek, R.; Culp, S.; Goldberg, H.

    1991-05-01

    Previous studies have identified a saturable site of d-({sup 3}H)amphetamine sequestration (AMSEQ) in rat brain synaptosomes. The present study characterized AMSEQ with respect to its subcellular, neuronal and regional distributions, ontogenetic development, pharmacological specificity and factors required for its maintenance. Although AMSEQ was reduced when assays were performed in Krebs' buffer incubated at 37{degree}C as compared to assays performed in isotonic Tris-sucrose buffer incubated at room temperature, the pharmacological profiles of AMSEQ were virtually identical under both conditions. AMSEQ was negligible in tissues outside the central nervous system, enriched in synaptosomes and partially reduced by striatal kainic acid lesion, indicatingmore » neuronal localization. The distribution of AMSEQ in the central nervous system was heterogenous. Highest levels were present in hypothalamus with progressively lower levels noted in parietal cortex, frontal cortex, striatum, thalamus, hippocampus, midbrain, cerebellum, pons-medulla and spinal cord. With regard to its ontogeny, AMSEQ increased early in neonatal life, reaching adult levels by postnatal day 14. Although the effects of amphetamine to abolish the transynaptosomal pH gradient suggest a possible role for this gradient in the maintenance of AMSEQ, the pharmacological profile of AMSEQ indicates that other factors are involved. An interaction with an intrasynaptosomal acid, such as N-acetylaspartate, may account for AMSEQ maintenance. AMSEQ did not possess a stereospecific preference for either d-(IC50 = 177 microM) or I-amphetamine (IC50 = 173 microM). However, the pharmacological profile of AMSEQ indicated structural specificity with antidepressants being relatively potent inhibitors. (Abstract Truncated)« less

  16. Phase transition in organic-inorganic perovskite (C9H19NH3)2 PbI2Br2 of long-chain alkylammonium

    NASA Astrophysics Data System (ADS)

    Abid, H.; Trigui, A.; Mlayah, A.; Hlil, E. K.; Abid, Y.

    2012-01-01

    Single perovskite slab alkylammonium lead iodides bromides (C9H19NH3)2PbI2Br2 is a new member of the family of hybrid organic-inorganic perovskite compounds. It exhibits a single structural phase transition with changes in the conformation of alkylammonium chains below room temperature. Differential scanning calorimetry (DSC), powder X-ray diffraction and FT-Raman spectroscopy were used to investigate this phase transition. These changes were characterized by a decreased conformational disorder of the methylene units of the alkyl chains. Phase transition was examined in light of the interesting optical properties of this material, as well as the relevance of this system as models for phase transitions in lipid bilayers.

  17. Standardisation of the (129)I, (151)Sm and (166m)Ho activity concentration using the CIEMAT/NIST efficiency tracing method.

    PubMed

    Altzitzoglou, Timotheos; Rožkov, Andrej

    2016-03-01

    The (129)I, (151)Sm and (166m)Ho standardisations using the CIEMAT/NIST efficiency tracing method, that have been carried out in the frame of the European Metrology Research Program project "Metrology for Radioactive Waste Management" are described. The radionuclide beta counting efficiencies were calculated using two computer codes CN2005 and MICELLE2. The sensitivity analysis of the code input parameters (ionization quenching factor, beta shape factor) on the calculated efficiencies was performed, and the results are discussed. The combined relative standard uncertainty of the standardisations of the (129)I, (151)Sm and (166m)Ho solutions were 0.4%, 0.5% and 0.4%, respectively. The stated precision obtained using the CIEMAT/NIST method is better than that previously reported in the literature obtained by the TDCR ((129)I), the 4πγ-NaI ((166m)Ho) counting or the CIEMAT/NIST method ((151)Sm). Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  18. (3H)-Saxitoxinol Metabolism and Elimination in the Rat

    DTIC Science & Technology

    1993-01-01

    Pnrne cn. 31,a BNo p. 90-)Q,19 T IC PfmnPn t 1Z in I I I Pri imt kntanE L E C T E 3 SEP23 1993I ~E" [3H-SAXITOXINOL METABOLISM AND ELIMINATION IN... clious , Fort __Detrick. Frederick. MD 21701-501 I. t’.SA. €R ecenred 8 Aprpe 1992: atuepwud 5 January 1993) l H. B. HINES. S. M. NASEEM and R. W...48. 72 and 144 hr post-injection. A 0.1 ml aliquot of each urine sample was assayed for total radioactivity. The remainder was frozen at - 20’ C until

  19. Reactive carbon-chain molecules: synthesis of 1-diazo-2,4-pentadiyne and spectroscopic characterization of triplet pentadiynylidene (H-C[triple bond]C-:C-C[triple bond]C-H).

    PubMed

    Bowling, Nathan P; Halter, Robert J; Hodges, Jonathan A; Seburg, Randal A; Thomas, Phillip S; Simmons, Christopher S; Stanton, John F; McMahon, Robert J

    2006-03-15

    1-Diazo-2,4-pentadiyne (6a), along with both monodeuterio isotopomers 6b and 6c, has been synthesized via a route that proceeds through diacetylene, 2,4-pentadiynal, and 2,4-pentadiynal tosylhydrazone. Photolysis of diazo compounds 6a-c (lambda > 444 nm; Ar or N2, 10 K) generates triplet carbenes HC5H (1) and HC5D (1-d), which have been characterized by IR, EPR, and UV/vis spectroscopy. Although many resonance structures contribute to the resonance hybrid for this highly unsaturated carbon-chain molecule, experiment and theory reveal that the structure is best depicted in terms of the dominant resonance contributor of penta-1,4-diyn-3-ylidene (diethynylcarbene, H-C[triple bond]C-:C-C[triple bond]C-H). Theory predicts an axially symmetric (D(infinity h)) structure and a triplet electronic ground state for 1 (CCSD(T)/ANO). Experimental IR frequencies and isotope shifts are in good agreement with computed values. The triplet EPR spectrum of 1 (absolute value(D/hc) = 0.6157 cm(-1), absolute value(E/hc) = 0.0006 cm(-1)) is consistent with an axially symmetric structure, and the Curie law behavior confirms that the triplet state is the ground state. The electronic absorption spectrum of 1 exhibits a weak transition near 400 nm with extensive vibronic coupling. Chemical trapping of triplet HC5H (1) in an O2-doped matrix affords the carbonyl oxide 16 derived exclusively from attack at the central carbon.

  20. Anhydrous versus hydrated N4-substituted 1H-pyrazolo[3,4-d]pyrimidine-4,6-diamines: hydrogen bonding in two and three dimensions.

    PubMed

    Trilleras, Jorge; Quiroga, Jairo; Cobo, Justo; Marchal, Antonio; Nogueras, Manuel; Low, John N; Glidewell, Christopher

    2008-10-01

    Ten new N(4)-substituted 1H-pyrazolo[3,4-d]pyrimidine-4,6-diamines have been synthesized and the structures of nine of them are reported here, falling into two clear groups, those which are stoichiometric hydrates and those which crystallize in solvent-free forms. In each of N(4)-methyl-N(4)-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine, C(12)H(12)N(6) (I), N(4)-cyclohexyl-N(4)-methyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine, C(12)H(18)N(6) (II), and N(4)-(3-chlorophenyl)-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine, C(11)H(9)ClN(6) (III), the molecules are linked into hydrogen-bonded sheets. The molecules of 2-{4-(6-amino-1H-pyrazolo[3,4-d]pyrimidin-4-yl)piperazin-1-yl}ethanol, C(11)H(17)N(7)O (IV), are linked into a three-dimensional framework, while the structure of N(4)-methyl-N(4)-(4-methylphenyl)-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine monohydrate, C(13)H(14)N(6) x H(2)O (V), is only two-dimensional despite the presence of five independent hydrogen bonds. The stoichiometric hemihydrates N(4)-ethyl-N(4)-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine hemihydrate, C(13)H(14)N(6) x 0.5 H(2)O (VI) and N(4)-(4-methoxyphenyl)-N(4)-methyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine hemihydrate, C(13)H(14)N(6)O x 0.5 H(2)O (VII), exhibit remarkably similar sheet structures, despite different space groups and Z' values, Z' = 0.5 in C2/c for (VI) and Z' = 1 in P1 for (VII). N(4)-4-Benzyl-N(4)-phenyl-1H-pyrazolo[3,4-d]pyrimidine-4,6-diamine monohydrate, C(18)H(16)N(6) x H(2)O (VIII), crystallizes with Z' = 2 in P2(1)/n, and the four independent molecular components are linked into sheets by a total of 11 intermolecular hydrogen bonds. The sheet structure in {4-(pyrrolidin-1-yl)-1H-pyrazolo[3,4-d]pyrimidine-6-amine} ethanol hemisolvate hemihydrate, C(9)H(12)N(6).0.5C(2)H(6)O x 0.5 H(2)O (IX), is built from the pyrimidine and water components only; it contains eight independent hydrogen bonds, and it very closely mimics the sheets in (VI) and (VII); the ethanol molecules are